uu.seUppsala University Publications
Change search
Link to record
Permanent link

Direct link
BETA
Lewén, Anders
Alternative names
Publications (10 of 25) Show all publications
Johnson, U., Enquist, H., Lewén, A., Howells, T., Nilsson, P., Ronne-Engström, E., . . . Enblad, P. (2017). Increased risk of critical CBF levels in SAH patients with actual CPP below calculated optimal CPP. Acta Neurochirurgica, 159(6), 1065-1071.
Open this publication in new window or tab >>Increased risk of critical CBF levels in SAH patients with actual CPP below calculated optimal CPP
Show others...
2017 (English)In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 159, no 6, 1065-1071 p.Article in journal (Refereed) Published
Abstract [en]

Background Cerebral pressure autoregulation can be quantified with the pressure reactivity index (PRx), based on the correlation between blood pressure and intracranial pressure. Using PRx optimal cerebral perfusion pressure (CPPopt) can be calculated, i.e., the level of CPP where autoregulation functions best. The relation between cerebral blood flow (CBF) and CPPopt has not been examined. The objective was to assess to which extent CPPopt can be calculated in SAH patients and to investigate CPPopt in relation to CBF.

Methods Retrospective study of prospectively collected data. CBF was measured bedside with Xenon-enhanced CT (Xe-CT). The difference between actual CPP and CPPopt was calculated (CPPa dagger). Correlations between CPPa dagger and CBF parameters were calculated with Spearman's rank order correlation coefficient (rho). Separate calculations were done using all patients (day 0-14 after onset) as well as in two subgroups (day 0-3 and day 4-14).

Results Eighty-two patients with 145 Xe-CT scans were studied. Automated calculation of CPPopt was possible in adjunct to 60% of the Xe-CT scans. Actual CPP < CPPopt was associated with higher numbers of low-flow regions (CBF < 10 ml/100 g/min) in both the early phase (day 0-3, n = 39, Spearman's rho = -0.38, p = 0.02) and late acute phase of the disease (day 4-14, n = 35, Spearman's rho = -0.39, p = 0.02). CPP level per se was not associated with CBF.

Conclusions Calculation of CPPopt is possible in a majority of patients with severe SAH. Actual CPP below CPPopt is associated with low CBF.

Keyword
cerebral blood flow, autoregulation, CPP, subarachnoid haemorrhage
National Category
Clinical Medicine
Research subject
Neurosurgery
Identifiers
urn:nbn:se:uu:diva-294191 (URN)10.1007/s00701-017-3139-7 (DOI)000401117700016 ()28361248 (PubMedID)
Available from: 2016-09-21 Created: 2016-05-18 Last updated: 2017-06-13Bibliographically approved
Rostami, E., Engquist, H., Howells, T., Ronne-Engström, E., Nilsson, P., Hillered, L. T., . . . Enblad, P. (2017). The Correlation between Cerebral Blood Flow Measured by Bedside Xenon-CT and Brain Chemistry Monitored by Microdialysis in the Acute Phase following Subarachnoid Hemorrhage. Frontiers in Neurology, 8, Article ID 369.
Open this publication in new window or tab >>The Correlation between Cerebral Blood Flow Measured by Bedside Xenon-CT and Brain Chemistry Monitored by Microdialysis in the Acute Phase following Subarachnoid Hemorrhage
Show others...
2017 (English)In: Frontiers in Neurology, ISSN 1664-2295, E-ISSN 1664-2295, Vol. 8, 369Article in journal (Refereed) Published
Abstract [en]

Cerebral microdialysis (MD) may be used in patients suffering from subarachnoid hemorrhage (SAH) to detect focal cerebral ischemia. The cerebral MD catheter is usually placed in the right frontal lobe and monitors the area surrounding the catheter. This generates the concern that a fall in cerebral blood flow (CBF) and ischemic events distant to the catheter may not be detected. We aimed to investigate if there is a difference in the association between the MD parameters and CBF measured around the MD catheter compared to global cortical CBF and to CBF in the vascular territories following SAH in the early acute phase. MD catheter was placed in the right frontal lobe of 30 SAH patients, and interstitial glucose, lactate, pyruvate, glycerol, and lactate/pyruvate ratio were measured hourly. CBF measurements were performed during day 0-3 after SAH. Global cortical CBF correlated strongly with CBF around the microdialysis catheter (CBF-MD) (r = 0.911, p ≤ 0.001). This was also the case for the anterior, middle, and posterior vascular territories in the right hemisphere. A significant negative correlation was seen between lactate and CBF-MD (r = -0.468, p = 0.009). The same relationship was observed between lactate and CBF in anterior vascular territory but not in the middle and posterior vascular territories. In conclusion, global CBF 0-3 days after severe SAH correlated strongly with CBF-MD. High lactate level was associated with low global CBF and low regional CBF in the right anterior vascular territory, when the MD catheter was placed in the right frontal lobe.

Keyword
Xenon-CT, cerebral blood flow, lactate, microdialysis, subarachnoid hemorrhage
National Category
Neurosciences
Identifiers
urn:nbn:se:uu:diva-330939 (URN)10.3389/fneur.2017.00369 (DOI)000407574600001 ()28824527 (PubMedID)
Available from: 2017-10-07 Created: 2017-10-07 Last updated: 2018-01-13Bibliographically approved
Ekmark-Lewén, S., Flygt, J., Fridgeirsdottir, G. A., Kiwanuka, O., Hanell, A., Meyerson, B. J., . . . Marklund, N. (2016). Diffuse traumatic axonal injury in mice induces complex behavioural alterations that are normalized by neutralization of interleukin-1β. European Journal of Neuroscience, 43(8), 1016-1033.
Open this publication in new window or tab >>Diffuse traumatic axonal injury in mice induces complex behavioural alterations that are normalized by neutralization of interleukin-1β
Show others...
2016 (English)In: European Journal of Neuroscience, ISSN 0953-816X, E-ISSN 1460-9568, Vol. 43, no 8, 1016-1033 p.Article in journal (Refereed) Published
Abstract [en]

Widespread traumatic axonal injury (TAI) results in brain network dysfunction, which commonly leads to persisting cognitive and behavioural impairments following traumatic brain injury (TBI). TBI induces a complex neuroinflammatory response, frequently located at sites of axonal pathology. The role of the pro-inflammatory cytokine interleukin (IL)-1 has not been established in TAI. An IL-1-neutralizing or a control antibody was administered intraperitoneally at 30min following central fluid percussion injury (cFPI), a mouse model of widespread TAI. Mice subjected to moderate cFPI (n=41) were compared with sham-injured controls (n=20) and untreated, naive mice (n=9). The anti-IL-1 antibody reached the target brain regions in adequate therapeutic concentrations (up to similar to 30g/brain tissue) at 24h post-injury in both cFPI (n=5) and sham-injured (n=3) mice, with lower concentrations at 72h post-injury (up to similar to 18g/g brain tissue in three cFPI mice). Functional outcome was analysed with the multivariate concentric square field (MCSF) test at 2 and 9days post-injury, and the Morris water maze (MWM) at 14-21days post-injury. Following TAI, the IL-1-neutralizing antibody resulted in an improved behavioural outcome, including normalized behavioural profiles in the MCSF test. The performance in the MWM probe (memory) trial was improved, although not in the learning trials. The IL-1-neutralizing treatment did not influence cerebral ventricle size or the number of microglia/macrophages. These findings support the hypothesis that IL-1 is an important contributor to the processes causing complex cognitive and behavioural disturbances following TAI.

Keyword
axonal injury, behavioural outcome, central fluid percussion injury, interleukin-1, traumatic brain injury
National Category
Neurology
Identifiers
urn:nbn:se:uu:diva-297130 (URN)10.1111/ejn.13190 (DOI)000374645700004 ()27091435 (PubMedID)
Funder
Swedish Research Council
Available from: 2016-06-22 Created: 2016-06-21 Last updated: 2017-11-28Bibliographically approved
Blomquist, E., Ronne Engström, E., Borota, L., Gál, G., Nilsson, K., Lewén, A., . . . Enblad, P. (2016). Positive correlation between occlusion rate and nidus size of proton beam treated brain arteriovenous malformations (AVMs). Acta Oncologica, 55(1), 105-112.
Open this publication in new window or tab >>Positive correlation between occlusion rate and nidus size of proton beam treated brain arteriovenous malformations (AVMs)
Show others...
2016 (English)In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 55, no 1, 105-112 p.Article in journal (Refereed) Published
Abstract [en]

BACKGROUND: Proton beam radiotherapy of arteriovenous malformations (AVM) in the brain has been performed in Uppsala since 1991. An earlier study based on the first 26 patients concluded that proton beam can be used for treating large and medium sized AVMs that were considered difficult to treat with photons due to the risk of side effects. In the present study we analyzed the result from treating the subsequent 65 patients.

MATERIAL AND METHODS: A retrospective review of the patients' medical records, treatment protocols and radiological results was done. Information about gender, age, presenting symptoms, clinical course, the size of AVM nidus and rate of occlusion was collected. Outcome parameters were the occlusion of the AVM, clinical outcome and side effects.

RESULTS: The rate of total occlusion was overall 68%. For target volume 0-2cm(3) it was 77%, for 3-10 cm(3) 80%, for 11-15 cm(3) 50% and for 16-51 cm(3) 20%. Those with total regress of the AVM had significantly smaller target volumes (p < 0.009) higher fraction dose (p < 0.001) as well as total dose (p < 0.004) compared to the rest. The target volume was an independent predictor of total occlusion (p = 0.03). There was no difference between those with and without total occlusion regarding mean age, gender distribution or symptoms at diagnosis. Forty-one patients developed a mild radiation-induced brain edema and this was more common in those that had total occlusion of the AVM. Two patients had brain hemorrhages after treatment. One of these had no effect and the other only partial occlusion from proton beams. Two thirds of those presenting with seizures reported an improved seizure situation after treatment.

CONCLUSION: Our observations agree with earlier results and show that proton beam irradiation is a treatment alternative for brain AVMs since it has a high occlusion rate even in larger AVMs.

National Category
Cancer and Oncology
Identifiers
urn:nbn:se:uu:diva-254040 (URN)10.3109/0284186X.2015.1043023 (DOI)000367007700015 ()25972265 (PubMedID)
Available from: 2015-06-04 Created: 2015-06-04 Last updated: 2017-12-04Bibliographically approved
Merzo, A., Lenell, S., Nyholm, L., Enblad, P. & Lewen, A. (2016). Promising clinical outcome of elderly with TBI after modern neurointensive care. Acta Neurochirurgica, 158(1), 125-133.
Open this publication in new window or tab >>Promising clinical outcome of elderly with TBI after modern neurointensive care
Show others...
2016 (English)In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 158, no 1, 125-133 p.Article in journal (Refereed) Published
Abstract [en]

The increasing number of elderly patients with traumatic brain injury (TBI) leads to specific neurointensive care (NIC) challenges. Therefore, elderly subjects with TBI need to be further studied. In this study we evaluated the demographics, management and outcome of elderly TBI patients receiving modern NIC. Patients referred to our NIC unit between 2008 and 2010 were included. Patients were divided in two age groups, elderly (E) a parts per thousand yen65 years and younger (Y) 64-15 years. Parameters studied were the dominant finding on CT scans, neurological motor skills and consciousness, type of monitoring, neurosurgical procedures/treatments and Glasgow Outcome Scale Extended score at 6 months after injury. Sixty-two E (22 %) and 222 Y (78 %) patients were included. Falls were more common in E (81 %) and vehicle accidents were more common in Y patients (37 %). Acute subdural hematoma was significantly more common in E (50 % of cases) compared to Y patients (18 %). Intracranial pressure was monitored in 44 % of E and 57 % of Y patients. Evacuation of significant mass lesions was performed more common in the E group. The NIC mortality was similar in both groups (4-6 %). Favorable outcome was observed in 72 % of Y and 51 % of E patients. At the time of follow-up 25 % of E and 7 % of Y patients had died. The outcome of elderly patients with TBI was significantly worse than in younger patients, as expected. However, as much as 51 % of the elderly patients showed a favorable outcome after NIC. We believe that these results encourage modern NIC in elderly patients with TBI. We need to study how secondary brain injury mechanisms differ in the older patients and to identify specific outcome predictors for elderly patients with TBI.

Keyword
Traumatic brain injury, Outcome, Elderly, Neurointensive care, Secondary injury
National Category
Neurology
Identifiers
urn:nbn:se:uu:diva-274421 (URN)10.1007/s00701-015-2639-6 (DOI)000366975000016 ()
Funder
Swedish Research Council
Available from: 2016-01-21 Created: 2016-01-21 Last updated: 2017-11-30Bibliographically approved
Lenell, S., Nyholm, L., Lewen, A. & Enblad, P. (2015). Updated periodic evaluation of standardized neurointensive care shows that it is possible to maintain a high level of favorable outcome even with increasing mean age. Acta Neurochirurgica, 157(3), 417-425.
Open this publication in new window or tab >>Updated periodic evaluation of standardized neurointensive care shows that it is possible to maintain a high level of favorable outcome even with increasing mean age
2015 (English)In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 157, no 3, 417-425 p.Article in journal (Refereed) Published
Abstract [en]

Periodic evaluation of neurointensive care (NIC) is important. There is a risk that quality of daily care declines and there may also be unrecognized changes in patient characteristics and management. The aim of this work was to investigate the characteristics and outcome for traumatic brain injury (TBI) patients in the period 2008-2009 in comparison with 1996-1997 and to some extent also with earlier periods. TBI patients 16-79 years old admitted from 2008 to 2009 were selected for the study. Glasgow Coma Scale Motor score at admission (GCS M), radiology, surgery, and outcome (Glasgow Outcome Extended Scale) were collected from Uppsala Traumatic Brain Injury Register. The study included 148 patients (mean age, 45 years). Patients > 60 years old increased from 16 % 1996-1997 to 30 % 2008-2009 (p < 0.01). The proportion of GCS M 4-6 were similar, 92 vs. 93 % (NS). In 1996-1997 patients, 73 % had diffuse injury (Marshall classification) compared to 77 % for the 2008-2009 period (NS). More patients underwent surgery during 2008-2009 (43 %) compared to 1996-1997 (32 %, p < 0.05). Good recovery increased and mortality decreased substantially from 1980-1981 to 1987-1988 and to 1996-1997, but then the results were unchanged in the 2008-2009 period, with 73 % favorable outcome and 11 % mortality. Mortality increased in GCS M 6-4, from 2.8 % in 1996-1997 to 10 % in 2008-2009 (p < 0.05); most of the patients that died had aggravating factors, e.g., high age, malignancy. A large-proportion favorable outcome was maintained despite that patients > 60 years with poorer prognosis doubled, indicating that the quality of NIC has increased or at least is unchanged. More surgery may have contributed to maintaining the large proportion of favorable outcome. For future improvements, more knowledge about TBI management in the elderly is required.

Keyword
Traumatic brain injury, Standardized neurosurgical intensive care, Periodic evaluation, Outcome, Quality register
National Category
Neurosciences
Identifiers
urn:nbn:se:uu:diva-248427 (URN)10.1007/s00701-014-2329-9 (DOI)000350027700009 ()25591801 (PubMedID)
Available from: 2015-04-10 Created: 2015-03-30 Last updated: 2018-01-11Bibliographically approved
Fischerström, A., Nyholm, L., Lewen, A. & Enblad, P. (2014). Acute neurosurgery for traumatic brain injury by general surgeons in Swedish county hospitals: A regional study. Acta Neurochirurgica, 156(1), 177-185.
Open this publication in new window or tab >>Acute neurosurgery for traumatic brain injury by general surgeons in Swedish county hospitals: A regional study
2014 (English)In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 156, no 1, 177-185 p.Article in journal (Refereed) Published
Abstract [en]

Traditionally acute life-saving evacuations of extracerebral haematomas are performed by general surgeons on vital indication in county hospitals in the Uppsala-A-rebro health care region in Sweden, a region characterized by long distances and a sparsely distributed population. Recently, it was stated in the guidelines for prehospital care of traumatic brain injury from the Scandinavian Neurosurgical Society that acute neurosurgery should not be performed in smaller hospitals without neurosurgical expertise. The aim of this study was to investigate: how often does acute decompressive neurosurgery occur in county hospitals in the Uppsala-A-rebro region today, what is the indication for surgery, and what is the clinical outcome? Finally, the goal was to evaluate whether the current practice in the Uppsala-A-rebro region should be revised. Patients referred to the neurointensive care unit at the Department of Neurosurgery in Uppsala after acute evacuation of intracranial haematomas in the county hospitals 2005-2010 were included in the study. Data was collected retrospectively from the medical records following a predefined protocol. The presence of vital indication, radiological and clinical results, and long-term outcome were evaluated. A total of 49 patients (17 epidural haematomas and 32 acute subdural haematomas) were included in the study. The operation was judged to have been performed on vital indication in all cases. The postoperative CT scan was improved in 92 % of the patients. The reaction level and pupillary reactions were significantly improved after surgery. Long-term outcomes showed 51 % favourable outcome, 33 % unfavourable outcome, and in 16 % the outcome was unknown. Looking at the indication for acute neurosurgery, the postoperative clinical and radiological results, and the long-term outcome, it appears that our regional policy regarding life-saving decompressive neurosurgery in county hospitals by general surgeons should not be changed. We suggest a curriculum aimed at educating general surgeons in acute neurosurgery.

Keyword
Traumatic brain injury, Acute subdural haematoma, Epidural haematoma, Acute neurosurgery, General surgeons, Local hospitals, Glasgow outcome score, Scandinavian guidelines
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:uu:diva-216721 (URN)10.1007/s00701-013-1932-5 (DOI)000329093100027 ()
Available from: 2014-01-27 Created: 2014-01-24 Last updated: 2017-12-06Bibliographically approved
Purins, K., Lewén, A., Hillered, L., Howells, T. & Enblad, P. (2014). Brain tissue oxygenation and cerebral metabolic patterns in focal and diffuse traumatic brain injury. Frontiers in Neurology, 5, Article ID 64.
Open this publication in new window or tab >>Brain tissue oxygenation and cerebral metabolic patterns in focal and diffuse traumatic brain injury
Show others...
2014 (English)In: Frontiers in Neurology, ISSN 1664-2295, E-ISSN 1664-2295, Vol. 5, 64Article in journal (Refereed) Published
Abstract [en]

Introduction: Neurointensive care of traumatic brain injury (TBI) patients is currently based on intracranial pressure (ICP) and cerebral perfusion pressure (CPP) targeted protocols. There are reasons to believe that knowledge of brain tissue oxygenation (BtipO2) would add information with the potential of improving patient outcome. The aim of this study was to examine BtipO2 and cerebral metabolism using the Neurovent-PTO probe and cerebral microdialysis (MD) in TBI patients.

Methods: Twenty-three severe TBI patients with monitoring of physiological parameters, ICP, CPP, BtipO2, and MD for biomarkers of energy metabolism (glucose, lactate, and pyruvate) and cellular distress (glutamate, glycerol) were included. Patients were grouped according to injury type (focal/diffuse) and placement of the Neurovent-PTO probe and MD catheter (injured/non-injured hemisphere).

Results: We observed different patterns in BtipO2 and MD biomarkers in diffuse and focal injury where placement of the probe also influenced the results (ipsilateral/contralateral). In all groups, despite fairly normal levels of ICP and CPP, increased MD levels of glutamate, glycerol, or the L/P ratio were observed at BtipO2 <5 mmHg, indicating increased vulnerability of the brain at this level.

Conclusion: Monitoring of BtipO2 adds important information in addition to traditional ICP and CPP surveillance. Because of the different metabolic responses to very low BtipO2 in the individual patient groups we submit that brain tissue oximetry is a complementary tool rather than an alternative to MD monitoring.

Keyword
brain tissue oxygenation, cerebral metabolism, traumatic brain injury, cerebral ischemia, Neurovent-PTO
National Category
Anesthesiology and Intensive Care
Research subject
Neurosurgery
Identifiers
urn:nbn:se:uu:diva-194684 (URN)10.3389/fneur.2014.00064 (DOI)000209629300064 ()24817863 (PubMedID)
Funder
Swedish Research CouncilThe Swedish Brain Foundation
Available from: 2013-02-18 Created: 2013-02-18 Last updated: 2017-12-06Bibliographically approved
Hillered, L., Dahlin, A. P., Clausen, F., Chu, J., Bergquist, J., Hjort, K., . . . Lewén, A. (2014). Cerebral microdialysis for protein biomarker monitoring in the neurointensive care setting - a technical approach. Frontiers in Neurology, 5, 245.
Open this publication in new window or tab >>Cerebral microdialysis for protein biomarker monitoring in the neurointensive care setting - a technical approach
Show others...
2014 (English)In: Frontiers in Neurology, ISSN 1664-2295, E-ISSN 1664-2295, Vol. 5, 245- p.Article in journal (Refereed) Published
Abstract [en]

Cerebral microdialysis (MD) was introduced as a neurochemical monitoring method in the early 1990s and is currently widely used for the sampling of low molecular weight molecules, signaling energy crisis, and cellular distress in the neurointensive care (NIC) setting. There is a growing interest in MD for harvesting of intracerebral protein biomarkers of secondary injury mechanisms in acute traumatic and neurovascular brain injury in the NIC community. The initial enthusiasm over the opportunity to sample protein biomarkers with high molecular weight cut-off MD catheters has dampened somewhat with the emerging realization of inherent methodological problems including protein-protein interaction, protein adhesion, and biofouling, causing an unstable in vivo performance (i.e., fluid recovery and extraction efficiency) of the MD catheter. This review will focus on the results of a multidisciplinary collaborative effort, within the Uppsala Berzelii Centre for Neurodiagnostics during the past several years, to study the features of the complex process of high molecular weight cut-off MD for protein biomarkers. This research has led to new methodology showing robust in vivo performance with optimized fluid recovery and improved extraction efficiency, allowing for more accurate biomarker monitoring. In combination with evolving analytical methodology allowing for multiplex biomarker analysis in ultra-small MD samples, a new opportunity opens up for high-resolution temporal mapping of secondary injury cascades, such as neuroinflammation and other cell injury reactions directly in the injured human brain. Such data may provide an important basis for improved characterization of complex injuries, e.g., traumatic and neurovascular brain injury, and help in defining targets and treatment windows for neuroprotective drug development.

National Category
Neurology Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-239227 (URN)10.3389/fneur.2014.00245 (DOI)25520696 (PubMedID)
Available from: 2014-12-19 Created: 2014-12-19 Last updated: 2017-12-05Bibliographically approved
Rostami, E., Engquist, H., Johnson, U., Howells, T., Ronne-Engström, E., Nilsson, P., . . . Enblad, P. (2014). Monitoring of Cerebral Blood Flow and Metabolism Bedside in Patients with Subarachnoid Hemorrhage - A Xenon-CT and Microdialysis Study. Frontiers in Neurology, 5, Article ID 89.
Open this publication in new window or tab >>Monitoring of Cerebral Blood Flow and Metabolism Bedside in Patients with Subarachnoid Hemorrhage - A Xenon-CT and Microdialysis Study
Show others...
2014 (English)In: Frontiers in Neurology, ISSN 1664-2295, E-ISSN 1664-2295, Vol. 5, 89Article in journal (Refereed) Published
Abstract [en]

Cerebral ischemia is the leading cause of morbidity and mortality following aneurysmal subarachnoid hemorrhage (SAH). Although 70% of the patients show angiographic vasospasm only 30% develop symptomatic vasospasm defined as delayed cerebral ischemia (DCI). Early detection and management of reversible ischemia is of critical importance in patients with SAH. Using a bedside Xenon enhanced computerized tomography (Xenon-CT) scanner makes it possible to measure quantitative regional Cerebral blood flow (CBF) bedside in the neurointensive care setting and intracerebral microdialysis (MD) is a method that offers the possibility to monitor the metabolic state of the brain continuously. Here, we present results from nine SAH patients with both MD monitoring and bedside Xenon-CT measurements. CBF measurements were performed within the first 72 h following bleeding. Six out of nine patients developed DCI at a later stage. Five out of six patients who developed DCI had initial global CBF below 26 ml/100 g/min whereas one had 53 ml/100 g/min. The three patients who did not develop clinical vasospasm all had initial global CBF above 27 ml/100 g/min. High lactate/pyruvate (L/P) ratio was associated with lower CBF values in the area surrounding the catheter. Five out of nine patients had L/P ratio ≥25 and four of these patients had CBF ≤ 22 ml/100 g/min. These preliminary results suggest that patients with initially low global CBF on Xenon-CT may be more likely to develop DCI. Initially low global CBF was accompanied with metabolic disturbances determined by the MD. Most importantly, pathological findings on the Xenon-CT and MD could be observed before any clinical signs of DCI. Combining bedside Xenon-CT and MD was found to be useful and feasible. Further studies are needed to evaluate if DCI can be detected before any other signs of DCI to prevent progress to infarction.

Keyword
cerebral blood flow, subarachnoid hemorrhage, neurointensive care, Xenon-CT, imaging, vasospasm, microdialysis
National Category
Neurosciences
Identifiers
urn:nbn:se:uu:diva-240427 (URN)10.3389/fneur.2014.00089 (DOI)000209629300087 ()24917850 (PubMedID)
Funder
Swedish Research Council
Available from: 2015-01-07 Created: 2015-01-07 Last updated: 2018-01-11Bibliographically approved
Organisations

Search in DiVA

Show all publications