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  • 201.
    Torkzad, Michael R.
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Suzuki, C.
    Tanaka, S.
    Palmer, G.
    Holm, T.
    Blomqvist, L.
    Morphological assessment of the interface between tumor and neighboring tissues, by magnetic resonance imaging, before and after radiotherapy in patients with locally advanced rectal cancer2008Ingår i: Acta radiologica (Stockholm, Sweden : 1987), ISSN 1600-0455, Vol. 49, nr 10, s. 1099-103Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Magnetic resonance imaging (MRI) in rectal cancer is sometimes performed after radiotherapy (MRI 2) to evaluate tumor response and to choose alternative forms of surgery. The accuracy of MRI 2 in distinguishing tumor delineation might be difficult due to fibrosis. PURPOSE: To evaluate the morphological changes in the interface between the tumor and neighboring organs on MRI 2 performed after radiotherapy, and to assess the accuracies of MRI before and after radiotherapy compared to histopathology after surgery. MATERIAL AND METHODS: Sixteen patients with locally advanced primary rectal cancer, with MRI before and after radiotherapy, were retrospectively studied, concerning the interface between the tumor and neighboring structures. The accuracies of MRI before and after radiotherapy were compared based on histopathology as a reference. RESULTS: The accuracies of both MRI before and after radiotherapy were moderate, with no additional value of MRI after radiotherapy compared to MRI before radiotherapy. The most predictive form of interface for involvement of a neighboring organ after radiotherapy was nodular growth of the tumor into a neighboring structure. CONCLUSION: The morphological assessment of pelvic MRI after preoperative radiotherapy does not provide any significant new information about tumor extent in patients with locally advanced rectal cancer.

  • 202.
    Torkzad, Michael R.
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Vargas, Roberto
    Tanaka, Chikako
    Blomqvist, Lennart
    Value of cine MRI for better visualization of the proximal small bowel in normal individuals2007Ingår i: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 17, nr 11, s. 2964-2968Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    While enteroclysis seems to be the most efficacious method in achieving bowel distension, enterographic methods have become widespread due to the unpleasantness of enteroclysis and the radiation involved with positioning the catheter. Cine images in MRI can be done without radiation. Our aim is to see if and how cine MR imaging can improve visualization of bowel loops by capturing them while distended. Ten healthy individuals were asked to drink up to 2,000 ml of an oral solution made locally over a 60-min period. Then they underwent MRI using coronal balanced fast field echo (b-FFE) covering small bowel loops. If the initial exam revealed collapsed bowel loops an additional 50 mg of erythromycine was given intravenously with the subject still in the scanner and then cine imaging was performed. The degree of distension of different segments of the small bowel was measured before and after cine imaging and compared. The distension score was significantly higher after addition of the cine images as well, being only significant for depiction of the duodenum and jejunum. Our preliminary study suggests that cine MRI can give better image depiction of the proximal small bowel in healthy volunteers, perhaps circumventing the need for enteroclysis in some cases. There is a need for validation of these results in patients with small bowel disease.

  • 203. Van't Hooft, Ingrid
    et al.
    Gavhed, Désirée
    Laurencikas, Evaldas
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Henter, Jan-Inge
    Neuropsychological sequelae in patients with neurodegenerative Langerhans cell histiocytosis2008Ingår i: Pediatric Blood & Cancer, ISSN 1545-5009, E-ISSN 1545-5017, Vol. 51, nr 5, s. 669-74Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Patients with Langerhans cell histiocytosis (LCH) may develop neurodegeneration and significant CNS sequelae, affecting a significant proportion of the patients. We here aimed to investigate the neuropsychological consequences in more detail. METHODS: Using an extensive neuropsychological test battery, we evaluated nine LCH patients, 6-20 years old, with radiological signs indicative of neurodegeneration. RESULTS: Altogether 3/9 patients performed below 1 SD of normal for age on full IQ. Detailed analysis revealed that 4/9 had deficient performance IQ, whereas 1/9 had subnormal verbal IQ (defined as below 1 SD). Furthermore, 3/8 patients showed slow speed of performance for age. Notably, 8/9 (89%) had deficient verbal working memory and 7/8 (88%) performed below normal on visual-spatial working memory. CONCLUSIONS: The results indicate a specific, uneven neuropsychological profile in patients affected by CNS-LCH, with a decline particularly on perceptual tasks whereas the verbal performance was not as negatively influenced. Furthermore, verbal and visual-spatial working memory functions were below normal for age in all but one patient studied. LCH may easily be misdiagnosed, but it is important that individuals affected by CNS-LCH are diagnosed to provide advice and support. It remains a challenge to find a treatment reducing this unfortunate neurodegeneration.

  • 204. Varelmann, Dirk
    et al.
    Muders, Thomas
    Zinserling, Jörg
    Guenther, Ulf
    Magnusson, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Hedenstierna, Göran
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Klinisk fysiologi.
    Putensen, Christian
    Wrigge, Hermann
    Cardiorespiratory effects of spontaneous breathing in two different models of experimental lung injury: a randomized controlled trial2008Ingår i: Critical Care, ISSN 1364-8535, E-ISSN 1466-609X, Vol. 12, nr 6, s. R135-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    INTRODUCTION: Acute lung injury (ALI) can result from various insults to the pulmonary tissue. Experimental and clinical data suggest that spontaneous breathing (SB) during pressure-controlled ventilation (PCV) in ALI results in better lung aeration and improved oxygenation. Our objective was to evaluate whether the addition of SB has different effects in two different models of ALI. METHODS: Forty-four pigs were randomly assigned to ALI resulting either from hydrochloric acid aspiration (HCl-ALI) or from increased intra-abdominal pressure plus intravenous oleic acid injections (OA-ALI) and were ventilated in PCV mode either with SB (PCV + SB) or without SB (PCV - SB). Cardiorespiratory variables were measured at baseline after induction of ALI and after 4 hours of treatment (PCV + SB or PCV - SB). Finally, density distributions and end-expiratory lung volume (EELV) were assessed by thoracic spiral computed tomography. RESULTS: PCV + SB improved arterial partial pressure of oxygen/inspiratory fraction of oxygen (PaO2/FiO2) by a reduction in intrapulmonary shunt fraction in HCl-ALI from 27% +/- 6% to 23% +/- 13% and in OA-ALI from 33% +/- 19% to 26% +/- 18%, whereas during PCV - SB PaO2/FiO2 deteriorated and shunt fraction increased in the HCl group from 28% +/- 8% to 37% +/- 17% and in the OA group from 32% +/- 12% to 47% +/- 17% (P < 0.05 for interaction time and treatment, but not ALI type). PCV + SB also resulted in higher EELV (HCl-ALI: 606 +/- 171 mL, OA-ALI: 439 +/- 90 mL) as compared with PCV - SB (HCl-ALI: 372 +/- 130 mL, OA-ALI: 192 +/- 51 mL, with P < 0.05 for interaction of time, treatment, and ALI type). CONCLUSIONS: SB improves oxygenation, reduces shunt fraction, and increases EELV in both models of ALI.

  • 205.
    Vidholm, Erik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Centrum för bildanalys. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datoriserad bildanalys.
    Nilsson, Sven
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datoriserad bildanalys. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Nyström, Ingela
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Centrum för bildanalys. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datoriserad bildanalys.
    Fast and robust semi-automatic liver segmentation with haptic interaction2006Ingår i: MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION - MICCAI 2006, PROCEEDINGS 4191, 2006, s. 774-781Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present a method for semi-automatic segmentation of the liver from CT scans. True 3D interaction with haptic feedback is used to facilitate initialization, i.e., seeding of a fast marching algorithm. Four users initialized 52 datasets and the mean interaction time was 40 seconds. The segmentation accuracy was verified by a radiologist. Volume measurements and segmentation precision show that the method has a high reproducibility.

  • 206.
    Wahlberg, Andreas
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Erikson, Uno
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Fuchs, Laszlo
    Andersson, Anders
    Attefall, Anna
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Dosin--a new pump device. Its construction and function2007Ingår i: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 112, nr 1, s. 83-93Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The cyclic flow of the Dosin(R) is useful in interventional radiology since it prevents clotting and increases the mixing with the blood. The flow rate varies from 0.03 mL/s to 5 mL/s and it is recommended to use fluid with a viscosity lower than 3 mPa.s. The outlet pressure is recommended below 300 mm Hg. The Dosin(R) must be replaced after each patient, alternatively after maximum 24h continuous use.

  • 207. Wahlberg, Andreas
    et al.
    Eriksson, Uno
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Attefall, Anna
    Andersson, Anders
    Gastrointestinal radiological investigations with a new pump device: experimental and clinical experiences2008Ingår i: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 113, nr 1, s. 73-78Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In an earlier paper a new pump device for medical applications was described. This enabled a continuous flow of saline, barium contrast agent and gases. We now report further study of this device: The use of gases was experimentally studied to give a basis for use in CT-colonography. We also report experiences from injection of barium contrast agent via a naso-duodenal tube for radiological investigation of the small intestine in patients with gastrointestinal suffering. The radiation exposure to the x-ray staff was reduced. The investigation procedure was standardised and shortened.

  • 208.
    Wang, Chen
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Melberg, Atle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Weis, Jan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Månsson, J-E
    Göteborgs universitet.
    Raininko, Raili
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    The earliest MR imaging and proton MR spectroscopy abnormalities in adult-onset Krabbe disease2007Ingår i: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 116, nr 4, s. 268-272Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Adult-onset Krabbe disease is an uncommon form of leukodystrophy. Its magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) manifestations are not well documented. AIM OF THE STUDY: To describe early MR findings in adult-onset Krabbe disease. MATERIALS AND METHODS: A 28-year-old woman who had spastic paraparesis and a 5-year history of gait problems underwent MRI of the brain and cervical spine. Proton MRS was performed at 1.5 T using a short echo time. Metabolites were analyzed in the areas of MR signal abnormalities and normal-appearing brain. Six healthy volunteers were examined as controls. RESULTS: MRI revealed changes in the upper corticospinal tracts, splenium and, minimally, adjacent to the atria of the lateral ventricles. MRS showed decreased creatine, choline, N-acetylaspartate and glutamate and probably elevated lactate in the upper corticospinal tract but not in the normal-appearing frontal lobe. The spinal cord was thin. Laboratory tests verified Krabbe disease. CONCLUSIONS: These results indicate early involvement of the upper corticospinal tract in adult-onset Krabbe disease. The cases reported earlier had imaging changes indicating a more advanced disease or no MR findings. Thinning of the spinal cord is a new finding in Krabbe disease.

  • 209.
    Wanhainen, Anders
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Kärlkirurgi.
    Ljungman, Christer
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Kärlkirurgi.
    Eriksson, Lars-Gunnar
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    "Homemade" oversized fenestrations for emergency endovascular repair of a mycotic saccular aortic aneurysm2010Ingår i: Journal of Vascular and Interventional Radiology, ISSN 1051-0443, E-ISSN 1535-7732, Vol. 21, nr 3, s. 405-406Artikel i tidskrift (Refereegranskat)
  • 210.
    Wanhainen, Anders
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Kärlkirurgi.
    Nyman, Rickard
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Eriksson, Mats-Ola
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Björck, Martin
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Kärlkirurgi.
    First report of a late type III endoleak from fabric tears of a Zenith stent graft2008Ingår i: Journal of vascular surgery, ISSN 0741-5214, Vol. 48, nr 3, s. 723-726Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report a case of a late type III endoleak from a hole in the fabric of the main body of a Zenith bifurcated endograft 7 years after implantation. Abdominal pain and a rapidly expanding aneurysm were eventually followed by rupture. The defect was detected at open surgery, whereas no evidence of endoleak was found at preoperative computed tomography (CT) or angiogram. The defect was repaired by a relining procedure with an Excluder stent graft. The patient, however, died 3 weeks after admission.

  • 211.
    Wanhainen, Anders
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Kärlkirurgi.
    Themudo, Raquel
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Lind, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Johansson, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Thoracic and abdominal aortic dimension in 70-year-old men and women: a population-based whole-body magnetic resonance imaging (MRI) study2008Ingår i: Journal of Vascular Surgery, ISSN 0741-5214, E-ISSN 1097-6809, Vol. 47, nr 3, s. 504-12Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: The aim of this population-based study was to determine the optimal dividing-line between normal aorta and aneurysm for different aortic segments in 70-year-old men and women by means of whole-body magnetic resonance imaging. METHODS: Two hundred thirty-one subjects (116 men), randomly recruited from a population-based cohort study, were included. The smallest outer diameter (dia) was measured on the axial survey scan on six predefined aortic segments: (1) ascending aorta, (2) descending aorta, (3) supraceliac aorta, (4) suprarenal aorta, (5) largest infrarenal abdominal aorta, and (6) aortic bifurcation. Relative aortic dia were calculated by dividing a given aortic dia by the suprarenal aortic dia. The dividing-line between normal aorta and aneurysm at different aortic segments was estimated by taking the mean dia +2 SD and/or mean ratio of the aortic segment to the suprarenal aorta +2 SD. RESULTS: The mean dia of the six segments were 4.0 cm (SD 0.4), 3.2 cm (0.3), 3.0 cm (0.3), 2.8 cm (0.3), 2.4 cm (0.5), and 2.3 cm (0.3) in men. The corresponding dia in women were 3.4 cm (0.4), 2.8 cm (0.3), 2.7 cm (0.3), 2.7 cm (0.3), 2.2 cm (0.3), and 2.0 cm (0.2). The mean ratio to the suprarenal aorta was 1.4 (SD 0.2) for the ascending aorta, 1.2 (0.1) for the descending aorta, and 0.9 (0.2) for the infrarenal aorta in men. The corresponding ratios in women were 1.3 (0.2), 1.0 (0.1), and 0.8 (0.1). CONCLUSION: For men the suggested dividing-line (dia and ratio) between normal aorta and aneurysm for the ascending aorta is 4.7 cm dia and 1.8 ratio, for the descending aorta 3.7 cm dia and 1.5 ratio, and for the infrarenal aorta is 3.0 cm dia and 1.1 ratio. The corresponding dividing-lines for women are 4.2 cm dia and 1.7 ratio, 3.3 cm dia and 1.3 ratio, and 2.7 cm dia and 1.0 ratio.

  • 212. Wassélius, Johan
    et al.
    Larsson, Stig
    Sundin, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Jacobsson, Hans
    Assessment of inactive, active and mixed atherosclerotic plaques by 18F-FDG-PET; an age group-based correlation with cardiovascular risk factors2009Ingår i: The international journal of cardiovascular imaging, ISSN 1569-5794, Vol. 25, nr 2, s. 133-40Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: The aim of this study was to assess the atherosclerotic plaques in a large asymptomatic population stratified based on age and sex. METHODS: [18F]-2-fluoro-2-deoxy-D-glucose (FDG)-PET/CT of 100 men and 100 women, divided in four age groups were examined to assess FDG-accumulating active, calcified inactive and mixed atherosclerotic plaques in eight defined vessel segments. RESULTS: There was a high correlation between the total number of cardiovascular risk factors and the number of FDG-accumulating active plaques as well as the number of calcified inactive plaques. There was a significant difference in the number of plaques between all age-groups except for active plaques in age groups 60-70 and 80-90 years. CONCLUSIONS: There is a correlation between the number of cardiovascular risk factors and the number of FDG-accumulating atherosclerotic lesions in this patient material. Statin-treatment was associated with significantly lower numbers of active plaques.

  • 213. Wassélius, Johan
    et al.
    Malmstedt, Jonas
    Kalin, Bo
    Larsson, Stig
    Sundin, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Hedin, Ulf
    Jacobsson, Hans
    High 18F-FDG Uptake in synthetic aortic vascular grafts on PET/CT in symptomatic and asymptomatic patients2008Ingår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 49, nr 10, s. 1601-5Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Graft infection is a serious complication to vascular surgery. The aim of this study was to assess (18)F-FDG uptake in vascular grafts in patients with or without symptoms of graft infection. METHODS: In all 2,045 patients examined by PET/CT at our clinic, 16 patients with synthetic aortic grafts were identified and reevaluated for (18)F-FDG accumulation. Clinical and biochemical data were obtained from patient records. RESULTS: High (18)F-FDG uptake was found in 10 of 12 grafts in the patients who underwent open surgery and in 1 of 4 grafts in patients who underwent endovascular aneurysm repair. On the basis of biochemical and clinical data, it was concluded that 1 of the 16 patients had a graft infection at the time of investigation. CONCLUSION: (18)F-FDG uptake in vascular grafts was found in the vast majority of patients without graft infection. The risk of a false-positive diagnosis of graft infection by (18)F-FDG PET/CT is evident.

  • 214.
    Weis, Jan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Hlavcak, Peter
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för genetik och patologi.
    Häggman, Mikael
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Urologkirurgi.
    Ortiz-Nieto, Francisco
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Bergman, Antonina
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Two-dimensional spectroscopic imaging for pretreatment evaluation of prostate cancer: comparison with the step-section histology after radical prostatectomy2009Ingår i: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 27, nr 1, s. 87-93Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: To minimize user and vendor dependence of the spectrum processing of prostate spectra, to measure the ratio of choline (Cho) plus creatine (Cr) to citrate (Cit) in the prostate tissue of normal volunteers and cancer patients, and to compare the results with pathologic findings after radical prostatectomy. MATERIALS AND METHODS: Four healthy volunteers and 13 patients with prostate cancer were measured. Measurements were performed using two-dimensional magnetic resonance spectroscopic imaging (MRSI) and endorectal coil. A standard vendor's spectrum processing approach has been modified. An original feature of this methodology was the combination of vendor-optimized and user-independent spectrum preprocessing in the scanner and user-independent quantitation in the environment of an MRUI software package. (Cho+Cr)/Cit ratio was used for the classification of prostate tissue. Results were compared with histopathology after radical prostatectomy. RESULTS: Eight of 13 cancer patients were classified as suspicious or very suspicious for cancer at spectroscopy, three were ambiguous for cancer and two patients were evaluated as false negative. A considerable overlap of metabolite ratios at various Gleason score was found. CONCLUSION: The proposed spectrum processing has the potential to improve the accuracy and user independency of the (Cho+Cr)/Cit quantitation. This study confirmed the previous results that a considerable overlap of (Cho+Cr)/Cit ratios exists at various Gleason score levels.

  • 215.
    Weis, Jan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ciray, Ipek
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ericsson, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Lindman, Henrik
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Åström, Gunnar
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Hemmingsson, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Spectroscopic imaging of bone marrow composition in vertebral bodies2001Ingår i: Magnetic Resonance Materials in Physics, Biology and Medicine, ISSN 0968-5243, E-ISSN 1352-8661, Vol. 13, nr 1, s. 15-18Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The proton spectroscopic imaging technique that uses read gradient during acquisition was used for the measurement of the proton spectra in the lumbar and thoracic part of the spine of a patient with breast cancer without known skeletal metastases. The bone marrow fat/water ratios were evaluated in the same location before and after chemotherapy treatment. The results were corrected for relaxation effects. The fat/water ratios showed a significant increase as a consequence of the bone marrow degradation process due to chemotherapy. The proposed spectroscopic imaging technique offers rapid acquisition of proton spectra from large volumes of the vertebral bodies.

  • 216.
    Weis, Jan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Covaciu, Lucian
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Anestesiologi och intensivvård.
    Rubertsson, Sten
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Anestesiologi och intensivvård.
    Allers, Mats
    Lunderquist, Anders
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Noninvasive monitoring of brain temperature during mild hypothermia2009Ingår i: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 27, nr 7, s. 923-932Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The main purpose of this study was to verify the feasibility of brain temperature mapping with high-spatial- and reduced-spectral-resolution magnetic resonance spectroscopic imaging (MRSI). A secondary goal was to determine the temperature coefficient of water chemical shift in the brain with and without internal spectral reference. The accuracy of the proposed MRSI method was verified using a water and vegetable oil phantom. Selective decrease of the brain temperature of pigs was induced by intranasal cooling. Temperature reductions between 2 degrees C and 4 degrees C were achieved within 20 min. The relative changes in temperature during the cooling process were monitored using MRSI. The reference temperature was measured with MR-compatible fiber-optic probes. Single-voxel (1)H MRS was used for measurement of absolute brain temperature at baseline and at the end of cooling. The temperature coefficient of the water chemical shift of brain tissue measured by MRSI without internal reference was -0.0192+/-0.0019 ppm/degrees C. The temperature coefficients of the water chemical shift relative to N-acetylaspartate, choline-containing compounds and creatine were -0.0096+/-0.0009, -0.0083+/-0.0007 and -0.0091+/-0.0011 ppm/degrees C, respectively. The results of this study indicate that MRSI with high spatial and reduced spectral resolutions is a reliable tool for monitoring long-term temperature changes in the brain.

  • 217.
    Weis, Jan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Biomedicinsk informatik och teknik.
    Johansson, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Courivaud, Frederic
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Karlsson, F. Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Quantification of intramyocellular lipids in obese subjects using spectroscopic imaging with high spatial resolution2007Ingår i: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 57, nr 1, s. 22-28Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Quantification of intramyocellular lipids (IMCL) in obese subjects by single-voxel spectroscopy (SVS) or conventional spectroscopic imaging (SI) often fails due to overlap of IMCL spectral lines by extramyocellular lipids (EMCL), and signal contamination from subcutaneous fat and bone marrow. This study demonstrates that these problems can be solved by high-resolution SI with 128 phase-encoding steps and a read gradient during acquisition. The small voxels obtained in this way facilitated differentiation between EMCL and IMCL. This method offers the possibility of studying different muscle groups and the variation of lipids within one muscle.

  • 218.
    Weis, Jan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Johansson, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ortiz-Nieto, Francisco
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Assessment of lipids in skeletal muscle by high-resolution spectroscopic imaging using fat as the internal standard: comparison with water referenced spectroscopy2008Ingår i: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 59, nr 6, s. 1259-1265Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The main purpose of the study was to compare proton (1H) single-voxel MR spectroscopy (MRS) with high-spatial-resolution spectroscopic imaging (MRSI) to determine the lipid content in human skeletal muscle. Unsuppressed water line was used as a concentration reference in the processing of single-voxel spectra. The spectrum from yellow bone marrow with a 100% fat content and probe with the vegetable oil served as internal and external reference for high-spatial-resolution MRSI, respectively. Very good correlation was found between lipid concentrations measured by water referenced single-voxel MRS and high-spatial-resolution MRSI with yellow bone marrow as the internal standard. Excellent correlation was found between total lipid concentrations estimated by high-spatial-resolution MRSI with vegetable oil as the external fat standard and yellow bone marrow as the internal reference. From comparison of single-voxel MRS and MRSI approaches, it follows that relaxation correction of the reference water and methylene fat line is inevitable in processing the standard single-voxel spectra. The high-resolution MRSI approach is recommended to avoid the problem of relaxation corrections and enables using vegetable oil as the external fat standard.

  • 219.
    Weis, Jan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Johansson, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ortiz-Nieto, Francisco
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Assessment of lipids in skeletal muscle by LCModel and AMARES2009Ingår i: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 30, nr 5, s. 1124-1129Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: To process single voxel spectra of the human skeletal muscle by using an advanced method for accurate, robust, and efficient spectral fitting (AMARES) and by linear combination of model spectra (LCModel). To determine absolute concentrations of extra- (EMCL) and intramyocellular lipids (IMCL). MATERIALS AND METHODS: Single-voxel proton magnetic resonance spectroscopy (PRESS) was used to obtain the spectra of the calf muscles. Unsuppressed water line was used as a concentration reference. A new prior knowledge for AMARES was proposed to estimate the concentrations of EMCL and IMCL. The prior knowledge was derived from the spectrum of vegetable oil. The results were compared with the values estimated by LCModel. Absolute concentrations of total lipid content in millimoles per kilogram wet weight were used for the comparisons. RESULTS: Absolute concentrations of total lipid content in skeletal muscle were estimated by AMARES and LCModel. Very good correlation of the total fat (EMCL + IMCL) and IMCL concentrations was achieved between both data processing approaches. CONCLUSION: Assessment the absolute concentrations of muscular lipids by AMARES and LCModel can be performed with comparable accuracy.

  • 220.
    Weis, Jan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Raininko, Raili
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Age dependence of metabolite concentrations in supraventricular white matter: A short echo time 1H MRS study2006Ingår i: 23rd Annual Scientific Meeting of European Society for Magnetic Resonance in Medicine and Biology, Warsaw, Poland., 2006, s. Suppl 1-33Konferensbidrag (Övrigt vetenskapligt)
  • 221.
    Weis, Jan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ring, Patrik
    Olofsson, Tommie
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för genetik och patologi.
    Ortiz-Nieto, Francisco
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Wikström, Johan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Short echo time MR spectroscopy of brain tumors: grading of cerebral gliomas by correlation analysis of normalized spectral amplitudes2010Ingår i: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 31, nr 1, s. 39-45Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: To process single voxel spectra of low- and high-grade gliomas. To propose correlation analysis of the scatter plots of normalized spectral amplitudes as a pattern recognition tool for the classification (grading) of brain tumors. To propose a spectrum processing approach that improves the differentiation of proton spectra with dominating macromolecule and lipid peaks. MATERIALS AND METHODS: LCModel was used to process spectra. Mean metabolite concentrations and mean normalized spectra were obtained for normal white matter and for gliomas. The mean spectra of macromolecules and lipids (ML) in the range 1.4-0.9 ppm, and mean difference spectra (DS) without ML and lactate were computed. Correlation analysis of the scatter plot of the patient and mean normalized spectral amplitudes and dispersion of the scatter plot points were used for classification and grading of tumors. RESULTS: It was found advantageous to perform the classifications using DS spectra. The shape of ML spectrum and concentration of tCr seem to be a good markers for glioma grade. CONCLUSION: Combining a qualitative comparison of the patient and mean DS spectra of the tumors using correlation analysis of normalized spectra amplitudes with a quantitative comparison of metabolite concentrations is a powerful tool in studying brain lesions.

  • 222. Whitaker, Iain S.
    et al.
    Rozen, Warren M.
    Smit, Jeroen M.
    Dimopoulou, Angeliki
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ashton, Mark W.
    Acosta, Rafael
    Peritoneo-cutaneous perforators in deep inferior epigastric perforator flaps: a cadaveric dissection and computed tomographic angiography study2009Ingår i: Microsurgery, ISSN 0738-1085, E-ISSN 1098-2752, Vol. 29, nr 2, s. 124-127Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Cutaneous perforators that do not originate from the deep inferior epigastric artery (DIEA) are rare, but may significantly affect operative outcome. Peritoneal-cutaneous perforators have been described as a source for augmenting the blood flow to a deep inferior epigastric perforator (DIEP) flap, however if unrecognized, may compromise flap survival. METHODS: We reviewed 375 DIEA perforator (DIEP) flaps (325 with preoperative CTA and 50 cadaveric dissections) to investigate the incidence of this anomaly. RESULTS: We detected this variation in 3/325 (1%) of DIEP flaps following preoperative computed tomography. In 1/50 (2%) of the cadaveric specimens, a peritoneal-cutaneous perforator was found and injected with lead oxide contrast. It was shown to fill the cutaneous veins of the majority of the lower abdominal integument. CONCLUSION: Peritoneal-cutaneous perforators are rare anatomical variations (4/375: 1.1%) that may have significant ramifications for surgery utilizing the vasculature of the abdominal wall. CTA was significantly able to detect this anomaly and aid operative planning. Preoperative CTA helps to safely identify individual vascular anatomy including rare variations.

  • 223. Whitaker, Iain S.
    et al.
    Smit, Jeroen M.
    Rozen, Warren
    Dimopoulou, Angeliki
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Acosta, Rafael
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Plastikkirurgi.
    Pre operative computed tomographic angiography (CTA): a valuable lesson in planning DIEP flaps2009Ingår i: Journal of plastic, reconstructive & aesthetic surgery : JPRAS, ISSN 1878-0539, Vol. 62, nr 4, s. 551-551Artikel i tidskrift (Refereegranskat)
  • 224.
    Wikström, Anna-Karin
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kvinnors och barns hälsa.
    Wikström, Johan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Larsson, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Klinisk kemi.
    Olovsson, Matts
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kvinnors och barns hälsa.
    Random albumin/creatinine ratio for quantification of proteinuria in manifest pre-eclampsia2006Ingår i: BJOG, ISSN 1470-0328, Vol. 113, nr 8, s. 930-934Artikel i tidskrift (Refereegranskat)
  • 225.
    Wikström, Anna-Karin
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kvinnors och barns hälsa, Obstetrik & gynekologi.
    Wikström, Johan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Olovsson, Matts
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kvinnors och barns hälsa, Obstetrik & gynekologi.
    Random albumin/creatinine ratio for quantification of proteinuria in manifest pre-eclampsia - Reply2007Ingår i: British Journal of Obstetrics and Gynecology, ISSN 1470-0328, E-ISSN 1471-0528, Vol. 114, nr 1, s. 120-120Artikel i tidskrift (Refereegranskat)
  • 226.
    Wikström, Anna-Karin
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kvinnors och barns hälsa, Obstetrik & gynekologi.
    Wikström, Johan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Olovsson, Matts
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kvinnors och barns hälsa.
    Random albumin/creatinine ratio for quantification of proteinuria in manifest pre-eclampsia - Reply2007Ingår i: British Journal of Obstetrics and Gynecology, ISSN 1470-0328, E-ISSN 1471-0528, Vol. 114, nr 1, s. 119-119Artikel i tidskrift (Refereegranskat)
  • 227.
    Wikström, Johan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Bjornerud, Atle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för radiologi.
    McGill, S.
    Johansson, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Venous saturation slab causes overestimation of stenosis length in two-dimensional time-of-flight magnetic resonance angiography2009Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 50, nr 1, s. 55-60Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: The use of downstream saturation slabs in two-dimensional time-of-flight magnetic resonance angiography (2D TOF MRA) of the arterial system eliminates signal from regions with countercurrent flow, as seen in veins, but possibly also beyond arterial stenoses because of flow turbulence. PURPOSE: To investigate the contribution of a downstream saturation slab to signal intensity (SI) loss beyond stenoses at 2D TOF MRA. MATERIAL AND METHODS: 2D TOF MRA was performed on a bifurcation phantom with a tight stenosis at 1.5T during pulsatile flow. Qualitative and quantitative evaluations of stenosis delineation were performed with different echo times (TE) (3.7 or 7.0 ms), spatial resolution (1 x 1 x 1 or 1 x 1 x 5 mm(3)), and with or without a downstream saturation slab. For reference, a high-resolution contrast-enhanced sequence without flow was obtained. RESULTS: The downstream saturation slab caused severe signal loss immediately distal to the stenosis, causing overestimation of stenosis length. This region corresponded with a region of poststenotic flow jet, where turbulence is expected. With increase in TE, there was some increased SI loss at the level of maximum stenosis. A lower spatial resolution resulted in overall poorer delineation of the stenosis. CONCLUSION: Using clinically relevant sequence parameters, the use of a downstream saturation slab at 2D TOF MRA was found to be a major contributor to signal loss in stenotic regions, which can result in an overestimation of stenosis length.

  • 228.
    Wikström, Johan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Hansen, Tomas
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Johansson, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Lind, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Lower extremity artery stenosis distribution in an unselected elderly population and its relation to a reduced ankle-brachial index2009Ingår i: Journal of vascular surgery, ISSN 0741-5214, Vol. 50, nr 2, s. 330-334Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: This study evaluated the distribution and degree of symmetry of lower extremity artery stenoses in an unselected elderly population and its relation to a reduced ankle-brachial index (ABI) measurement. METHODS: This was a population-based study set in a university hospital comprising 306 randomly selected 70-year-old individuals participating in the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study. Whole-body magnetic resonance angiography (MRA) and bilateral ABI measurements were performed in each participant. The prevalence of stenosis >/=50% was evaluated in nine different arterial segments in both legs: common iliac artery (CIA), external iliac artery (EIA), common femoral artery (CFA), superficial femoral artery (SFA), popliteal artery (PA), tibioperoneal trunk (TPTr), anterior tibial artery (ATA), posterior tibial artery (PTA), and peroneal artery. The relations between the prevalences of stenosis in different arterial segments in the right and left leg were assessed. An evaluation was made of the relation between a >/=50% stenosis and an ABI <0.9 in the different segments. RESULTS: The prevalence of stenosis was 0% to 21%. In all segments, a stenosis was more commonly found in one of the legs only than in both legs. The prevalence of >/=50% stenosis in the right leg only, left leg only, and both legs was 0.3%, 0.7%, and 0% in the CIA; 0.3%, 1.0%, and 0.7% in the EIA; 0%, 0%, and 0% in the CFA; 2.0%, 1.3%, and 0.7% in the SFA; 0.7%, 0.7%, and 0.3% in the PA; 1.0%, 0.7%, and 0% in the TPTr; 5.6%, 6.3%, and 8.6% in the ATA; 0.7%, 1.7%, and 0% in the peroneal artery; and in 2.0%, 2.7%, and 3.4% in the PTA. When the legs were compared, a significant correlation was found for the presence of a >/=50% stenosis in the EIA, SFA, PA, ATA, and PTA. Seventeen participants showed ABI <0.9. In logistic regression analysis with ABI <0.9 as dependent variable, stenosis in SFA, ATA, and PTA were the major independent variables to explain a low ABI in both of the legs. CONCLUSIONS: The distribution of stenosis differs substantially when legs are compared. Despite this difference, stenosis in SFA, ATA, and PTA was the major determinant of a low ABI in both of the legs.

  • 229.
    Wikström, Johan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Hansen, Tomas
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Johansson, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Lind, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ankle brachial index <0.9 underestimates the prevalence of peripheral artery occlusive disease assessed with whole-body magnetic resonance angiography in the elderly2008Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 49, nr 2, s. 143-149Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Whole-body magnetic resonance angiography (WBMRA) permits noninvasive vascular assessment, which can be utilized in epidemiological studies. PURPOSE: To assess the relation between a low ankle brachial index (ABI) and high-grade stenoses in the pelvic and leg arteries in the elderly. MATERIAL AND METHODS: WBMRA was performed in a population sample of 306 subjects aged 70 years. The arteries below the aortic bifurcation were graded after the most severe stenosis according to one of three grades: 0-49% stenosis, 50-99% stenosis, or occlusion. ABI was calculated for each side. RESULTS: There were assessable WBMRA and ABI examinations in 268 (right side), 265 (left side), and 258 cases (both sides). At least one > or =50% stenosis was found in 19% (right side), 23% (left side), and 28% (on at least one side) of the cases. The corresponding prevalences for ABI <0.9 were 4.5%, 4.2%, and 6.6%. An ABI cut-off value of 0.9 resulted in a sensitivity, specificity, and positive and negative predictive value of 20%, 99%, 83%, and 84% on the right side, and 15%, 99%, 82%, and 80% on the left side, respectively, for the presence of a > or =50% stenosis in the pelvic or leg arteries. CONCLUSION: An ABI <0.9 underestimates the prevalence of peripheral arterial occlusive disease in the general elderly population.

  • 230.
    Wikström, Johan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Johansson, Lars
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Karacagil, Sadettin
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper.
    Ahlström, Håkan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Correlation of femoral artery flow velocity waveform with ipsilateral iliac artery stenoses assessed with magnetic resonance imaging2007Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 48, nr 4, s. 422-430Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Magnetic resonance (MR) permits quantitative flow velocity measurements that could be used to detect changes in the curve profile downstream of a high-grade stenosis. Purpose: To assess whether MR flow measurements can be used to detect iliac artery stenoses. Material and Methods: Contrast-enhanced magnetic resonance angiography (MRA) and quantitative flow measurements in the lower aorta and proximal femoral arteries were performed in 29 patients with suspected iliac artery stenoses. Stenoses were graded into five degrees: 0%, 1-49%, 50-74%, 75-99%, and 100% diameter reduction. The femoral artery waveforms were evaluated qualitatively by two independent reviewers regarding peak systolic velocity (PSV), aortofemoral difference in time-to-peak (TTP), systolic acceleration (SA), curve-shape index (CSI), and the presence of an early diastolic flow reversal. The correlation between these parameters and the degree of stenosis was assessed. Results: A significant correlation with degree of stenosis was observed for the qualitative flow waveform evaluations, with a high degree of interobserver agreement (=0.84). A significant correlation was also found between degree of stenosis and PSV, TTP, SA, CSI, and presence of diastolic flow reversal. The flow velocity pattern, however, remained unchanged, both qualitatively and quantitatively, up to a stenosis degree of at least 75%. Conclusion: Iliac artery stenoses cause femoral artery flow waveform changes that can be detected with MRI, but only at high-grade levels.

  • 231.
    Wikström, Johan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ronne-Engström, E.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Neurokirurgi.
    Gal, Gyula
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Enblad, P.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Neurokirurgi.
    Tovi, Metin
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Three-dimensional time-of-flight (3D TOF) magnetic resonance angiography (MRA) and contrast-enhanced MRA of intracranial aneurysms treated with platinum coils2008Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 49, nr 2, s. 190-6Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Contrast-enhanced magnetic resonance angiography (CE-MRA) is less prone to flow-related signal intensity loss than three-dimensional time-of-flight (3D TOF) MRA and may therefore be more sensitive for detection of residual patency in platinum coil-treated intracranial aneurysms. Purpose: To compare MRA and CE-MRA in the follow-up of intracranial aneurysms treated with platinum coils. MATERIAL AND METHODS: CE-MRA and 3D TOF MRA (pre- and postcontrast injection) of the intracranial vasculature was performed at 1.5T in 38 patients (47 aneurysms) referred for DSA in the follow-up of coiled intracranial aneurysms. RESULTS: DSA showed aneurysm patency in 22/47 investigations. Patent aneurysm components were observed with CE-MRA in 18/22 cases, and with 3D TOF MRA in 21/22 cases. There was no significant difference in patent aneurysm component size between CE-MRA and 3D TOF MRA. In addition, CE-MRA showed six, 3D TOF MRA before contrast injection showed seven, and 3D TOF MRA after contrast injection showed eight cases with patent aneurysm components not observed on DSA. CONCLUSION: 3D TOF MRA was highly sensitive for detection of patent aneurysm components, and at least as sensitive as CE-MRA. Residual aneurysm patency seems to be better visualized with MRA than with DSA in some cases.

  • 232. Winalski, Carl S.
    et al.
    Alparslan, Leyla
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Imaging of articular cartilage injuries of the lower extremity2008Ingår i: Seminars in Musculoskeletal Radiology, ISSN 1089-7860, E-ISSN 1098-898X, Vol. 12, nr 4, s. 283-301Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Imaging has become an important clinical tool in the evaluation of articular cartilage, both in the clinical and research setting. This article reviews the mechanisms of articular cartilage injury in the lower extremities and their implications. Specific examples of acute and chronic repetitive injuries in the hip, knee, and ankle are used to demonstrate the characteristics of articular cartilage lesions on magnetic resonance imaging and multidetector computed tomographic arthrography. Loss of meniscal function in the knee and femoroacetabular impingement in the hip represent sources of repetitive cartilage injury that predispose the joint to osteoarthritis. Acute cartilage injury is exemplified by osteochondral lesions of the talus, which may result in post-traumatic osteoarthritis. Recognition of early cartilage damage and associated lesions may help determine the proper treatment for the patient to delay or prevent progression to osteoarthritis.

  • 233. Wirestam, Ronnie
    et al.
    Thilmann, Oliver
    Knutsson, Linda
    Bjorkman-Burtscher, Isabella M.
    Larsson, Elna-Marie
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Ståhlberg, Freddy
    Comparison of quantitative dynamic susceptibility-contrast MRI perfusion estimates obtained using different contrast-agent administration schemes at 3 T2010Ingår i: European Journal of Radiology, ISSN 0720-048X, E-ISSN 1872-7727, Vol. 75, nr 1, s. E86-E91Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Absolute cerebral perfusion parameters were obtained by dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) carried out using different contrast-agent administration protocols. Sixteen healthy volunteers underwent three separate DSC-MRI examinations each, receiving single-dose (0.1 mmol/kg b.w.) gadobutrol, double-dose gadobutrol and single-dose gadobenate-dimeglumine on different occasions. DSC-MRI was performed using single-shot gradient-echo echo-planar imaging at 3 T. The arterial input functions (AIFs) were averages (4-9 pixels) of arterial curves from middle cerebral artery branches, automatically identified according to standard criteria. Absolute estimates of cerebral blood volume (CBV), cerebral blood flow (CBF) and mean transit time (MTT) were calculated without corrections for non-linear contrast-agent (CA) response in blood or for different T2* relaxivities in tissue and artery. Perfusion estimates obtained using single and double dose of gadobutrol correlated moderately well, while the relationship between estimates obtained using gadobutrol and gadobenate-dimeglumine showed generally lower correlation. The observed degree of CBV and CBF overestimation, compared with literature values, was most likely caused by different T2* relaxivities in blood and tissue in combination with partial-volume effects. The present results showed increased absolute values of CBV and CBF at higher dose, not predicted by the assumption of a quadratic response to contrast-agent concentration in blood. This indicates that the signal components of measured AIFs were not purely of arterial origin and that arterial signal components were more effectively extinguished at higher CA dose. This study also indicates that it may not be completely straightforward to compare absolute perfusion estimates obtained with different CA administration routines. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

  • 234. Wrigge, Hermann
    et al.
    Zinserling, Jörg
    Muders, Thomas
    Vareimann, Dirk
    Günther, Ulf
    von der Groeben, Cornelius
    Magnusson, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Hedenstierna, Göran
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Putensen, Christian
    Electrical impedance tomography compared with thoracic computed tomography during a slow inflation maneuver in experimental models of lung injury2008Ingår i: Critical Care Medicine, ISSN 0090-3493, E-ISSN 1530-0293, Vol. 36, nr 3, s. 903-909Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: To determine the validity of functional electric impedance tomography to monitor regional ventilation distribution in experimental acute lung injury, and to develop a simple electric impedance tomography index detecting alveolar recruitment. DESIGN: Randomized prospective experimental study. SETTING: Academic research laboratory. SUBJECTS: Sixteen anesthetized, tracheotomized, and mechanically ventilated pigs. INTERVENTIONS: Acute lung injury was induced either by acid aspiration (direct acute lung injury) or by abdominal hypertension plus oleic acid injection (indirect acute lung injury) in ten pigs. Six pigs with normal lungs were studied as a control group and with endotracheal suction-related atelectasis. After 4 hrs of mechanical ventilation, a slow inflation was performed. MEASUREMENTS AND MAIN RESULTS: During slow inflation, simultaneous measurements of regional ventilation by electric impedance tomography and dynamic computed tomography were highly correlated in quadrants of a transversal thoracic plane (r2 = .63-.88, p < .0001, bias <5%) in both direct and indirect acute lung injury. Variability between methods was lower in direct than indirect acute lung injury (11 +/- 2% vs. 18 +/- 3%, respectively, p < .05). Electric impedance tomography indexes to detect alveolar recruitment were determined by mathematical curve analysis of regional impedance time curves. Empirical tests of different methods revealed that regional ventilation delay, that is, time delay of regional impedance time curve to reach a threshold, correlated well with recruited volume as measured by CT (r2 = .63). Correlation coefficients in subgroups were r2 = .71 and r2 = .48 in pigs with normal lungs with and without closed suction related atelectasis and r2 = .79 in pigs subject to indirect acute lung injury, respectively, whereas no significant correlation was found in pigs undergoing direct acute lung injury. CONCLUSIONS: Electric impedance tomography allows assessment of regional ventilation distribution and recruitment in experimental models of direct and indirect acute lung injury as well as normal lungs. Except for pigs with direct acute lung injury, regional ventilation delay determined during a slow inflation from impedance time curves appears to be a simple index for clinical monitoring of alveolar recruitment.

  • 235.
    Örlefors, Håkan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Sundin, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Fasth, Karl-Johan
    Öberg, Kjell
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Långström, Bengt
    Eriksson, Barbro
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Bergström, Mats
    Demonstration of high monoamineoxidase-A levels in neuroendocrine gastroenteropancreatic tumors in vitro and in vivo: tumor visualization using positron emission tomography with 11C-harmine2003Ingår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 30, nr 6, s. 669-679Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background and Aims: A majority of neuroendocrine gastroenteropancreatic (GEP) tumors can be detected by conventional radiological methods and scintigraphic techniques. Still there are problems to visualize small tumor lesions and non-functioning tumors. The aim of this study was to investigate some of the monoamine processing pathways of neuroendocrine GEP-tumors and try to find a new tracer substance for in vivo characterization and visualization by Positron Emission Tomography (PET).

    Subjects and Methods: Autoradiography of tumor sections from 8 midgut carcinoids (MGC) and 8 endocrine pancreatic tumors (EPT) was performed with C-11-labeled tracers for serotonin and dopamine transporters, serotonin HT2A-, dopamine D1- and muscarinic receptors and for monoamine oxidase A (MAO-A). The in vitro results initiated PET studies with C-11-Harmine in 4 patients with MGC and 7 patients with EPT (one insulinoma, two glucagonomas and four non-functioning EPT).

    Results: The MAO-A-ligand Harmine expressed specific in vitro binding of 87 +/- 21% for MGC and 125 +/- 50% for EPT, compared to reference tissue (rat brain, 100%). All other substances showed relatively low specific binding. C-11-harmine-PET could visualize tumors in all patients. The mean standardized uptake value (SUV) for MGC was 7.5 +/- 3.9 and for EPT 12.9 +/- 2.7, whereas the SUV of normal liver, intestine and pancreas were 3.1 +/- 0.5, 3.4 +/- 1.2 and 8.9 +/- 3.0 respectively. Conclusions: This study demonstrates in vitro and in vivo that neuroendocrine GEP-tumors are characterized by a high MAO-A-expression, thereby adding to the similarities of neuronal and neuroendocrine tissue. It also indicates a possible application for C-11-harmine as a new PET-tracer for neuroendocrine GEP-tumors with the potential to visualize also non-functioning EPT's.

  • 236.
    Örlefors, Håkan
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Sundin, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Lu, L.
    Öberg, Kjell
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Långström, Bengt
    Eriksson, Barbro
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Bergström, M.
    Carbidopa pretreatment improves image interpretation and visualisation of carcinoid tumours with 11C-5-hydroxytryptophan positron emission tomography2006Ingår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 33, nr 1, s. 60-65Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: Positron emission tomography (PET) with 11C-5-hydroxytryptophan (5-HTP) as tracer is a promising imaging instrument in the management of patients with neuroendocrine tumours (NETs). However, high radioactivity concentrations in the urinary collecting system sometimes produce image reconstruction artefacts that can make detection of small NETs difficult. As a means to decrease urinary excretion of radioactivity and thereby improve image quality, we examined the effect of pretreatment with carbidopa (CD), a peripheral inhibitor of aromatic amino acid decarboxylase (AADC), which converts 5-HTP to serotonin (5-hydroxytryptamine, 5-HT). METHODS: Six patients with midgut carcinoid metastases were examined with 11C-5-HTP PET before and 1 h after oral administration of 100 or 200 mg of CD. RESULTS: There was a fourfold significant reduction of tracer uptake in the urinary collecting system after CD administration (p=0.0277, n=6), with a mean standard uptake value (SUV) of 155+/-195 before CD and 39+/-14 after CD. In tumour lesions there was a significant increase in SUV after CD administration (p<0. 0001, n=18), with a mean SUV of 11+/-3 before CD and 14+/-3 after CD. There was no difference between the doses (100 and 200 mg) of CD in this respect. In all patients, image interpretation and tumour detection were markedly improved after CD administration. CONCLUSION: We conclude that CD premedication improves 11C-5-HTP PET image quality and facilitates detection of NET lesions. Because of the similarity of metabolic pathways, this method could probably be applied to improve PET imaging using other tracers like 18F-DOPA and 11C-DOPA.

  • 237.
    Örlén, Hanna
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för genetik och patologi.
    Melberg, Atle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Raininko, Raili
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för radiologi.
    Kumlien, Eva
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Entesarian, Miriam
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för genetik och patologi.
    Söderberg, Per
    Department of Ophthalmology, Västerås Hospital.
    Påhlman, Magnus
    Darin, Niklas
    Kyllerman, Mårten
    Holmberg, Eva
    Engler, Henry
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Eriksson, Urban
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Dahl, Niklas
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för genetik och patologi.
    SPG11 mutations cause Kjellin syndrome, a hereditary spastic paraplegia with thin corpus callosum and central retinal degeneration2009Ingår i: American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, ISSN 1552-4841, E-ISSN 1552-485X, Vol. 150B, nr 7, s. 984-992Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Autosomal recessive hereditary spastic paraplegia (ARHSP) with thin corpus callosum (TCC) is genetically heterogenous and approximately 35% of patients carry mutations in either of the SPG11 or SPG15 genes. Disease onset is during the first three decades of life with spastic paraplegia and mental impairment. Peripheral neuropathy and amyotrophy may occur. Kjellin syndrome is characterized by central retinal degeneration in addition to ARHSP-TCC and the disease is associated with mutations in the SPG15 gene. We identified five patients in four unrelated kindreds with spastic paraplegia and mental impairment. Magnetic resonance imaging revealed TCC, atrophy elsewhere in the brain and increased T2 signal intensity in the periventricular white matter. Probands from the four kindreds were screened for mutations in the SPG11 gene. All patients were found homozygous or compound heterozygous for truncating SPG11 mutations of which four are reported for the first time. Ophthalmological investigations revealed that the four index cases have central retinal degeneration consistent with Kjellin syndrome. PET examinations with N-[11C-methyl]-L-deuterodeprenyl (DED) and fluor-18 2-fluorodeoxyglucose (FDG) were performed in two patients with Kjellin syndrome. We observed a reduced glucose uptake in the thalami, anterior cingulum, and sensorimotor cortex indicating neuronal loss, and an increased DED binding in the thalami and pons which suggests astrogliosis. From our results we extend the SPG11 associated phenotype to comprise also Kjellin syndrome, previously found to be associated with mutations in the SPG15 gene. We anticipate that degeneration of the central retina is a common and previously unrecognized feature in SPG11 related disease.

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