Incomplete hippocampal inversion in patients with focal epilepsy without known etiology and focal MRI abnormalities.
2016 (English)In: Neuroradiology Vol 58: Suppl.1, Springer, 2016, Vol. 58, S21- p.Conference paper, Abstract (Refereed)
Incomplete hippocampal inversion in patients with focal epilepsy without known etiology and focal MRI abnormalities
PURPOSE: Incomplete hippocampal inversion (IHI) is more common in patients with epilepsy than in subjects without epilepsy but is probably not an etiological factor. IHI frequency varies in different types of epilepsy. Our purpose was to evaluate the hippocampi of patients having focal epilepsy with unknown etiology and without focal abnormalities on MRI (EPue).
METHODS: MRIs of 58 patients with EPue and 147 neurologically healthy controls were evaluated. Hippocampal volumetry could be performed in 54 of the patients. 47 controls, preferably those having IHI, were chosen for volumetry. The findings were compared with seizure semiology and EEG findings.
RESULTS: 30/58 patients (52%) had IHI (18 left, 12 bilateral). 28/147 controls (19%) had IHI (20 left, 8 bilateral) (p<0.001). In subjects studied with volumetry, 27/54 patients (50%) and 23/47 selected controls (49%) had IHI. In patients, IHI was found on the left in 15 and bilaterally in 12. In controls, the numbers were 16 and 5, respectively. The left hippocampus was smaller in 48 patients and in 46 controls. Asymmetry index (AI) was >0.10 in 16 patients (30%) and in 3 controls (6.5%) (p<0.01). Among 10 patients having IHI and AI >0.10, six had temporal lobe semiology. One of them had bilateral IHI, 5 had IHI on the left. EEG foci were ipsilateral to IHI in 3, contralateral in 2.
CONCLUSIONS: IHI was significantly more common in EPue patients than in controls. Hippocampal volume asymmetry was more prominent in the patients. Temporal semiology and EEG focus were not obviously related to IHI.
Place, publisher, year, edition, pages
Springer, 2016. Vol. 58, S21- p.
Neuroradiology, Vol 58: Suppl. 1
Radiology, Nuclear Medicine and Medical Imaging
Research subject Radiology
IdentifiersURN: urn:nbn:se:uu:diva-309041OAI: oai:DiVA.org:uu-309041DiVA: diva2:1051421
European Society of Neuroradiology 2016