title: Incomplete Circle of Willis: A risk factor for mesial temporal sclerosis?
abstract: The aim of this study was to investigate whether there may be a correlation between the anatomical variants of Circle of Willis (CoW) and presence/laterality of mesial temporal sclerosis (MTS).
  
  
  
  We retrospectively identified the CoW variants on Wada angiograms in 71 patients with pathologically proven MTS. Angiograms were interpreted by two radiologists independently and blinded to clinical data. We divided the anterior and posterior components of the CoW into functionally complete and functionally incomplete groups. We then sought its correlation with the presence and laterality of MTS.
  
  
  
  No statistically significant relationship was found between the functional status of the anterior circulation and the laterality of the MTS (p=0.657). Relationship of the posterior incomplete circle to MTS was statistically significant on both sides (p=0.023 for the left, p=0.04 for the right), with an effect size moderate to large for the left side and moderate for the right side. Although the fetal variant appeared to be related to the ipsilateral MTS, it did not reach to a level of statistical significance (p=0.15).
  
  
  
  The study demonstrates a statistically significant association of the incomplete posterior circulation of the CoW to the presence of ipsilateral MTS. Further studies in larger patient populations may be needed to seek whether an incomplete circulation may facilitate development of MTS, especially affecting the watershed zones.
authors.affiliation: Rush University Medical Center, Department of Radiology & Nuclear Medicine, 1725 West Harrison Street, Suite 437, Chicago, IL 60612, USA. Electronic address: radiologistgokhan@gmail.com.
authors.forename: Gokhan
authors.initials: G
authors.lastname: Kuyumcu
authors.affiliation: Rush University Medical Center, Department of Neurosurgery, 1725 West Harrison Street, Suite 855, Chicago, IL 60612, USA. Electronic address: Richard_W_Byrne@rush.edu.
authors.forename: Richard W
authors.initials: RW
authors.lastname: Byrne
authors.affiliation: Rush University Medical Center, Department of Radiology & Nuclear Medicine, 1725 West Harrison Street, Suite 437, Chicago, IL 60612, USA; Rush Alzheimer's Disease Center, Johnston R Bowman Health Center, 600 S. Paulina Street, Chicago, IL, 60612, USA. Electronic address: rjdawe@gmail.com.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Dawe
authors.affiliation: Rush University Medical Center, Department of Radiology & Nuclear Medicine, 1725 West Harrison Street, Suite 437, Chicago, IL 60612, USA. Electronic address: Mehmet_Kocak@rush.edu.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Kocak
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002941:Circle of Willis / Q000473:pathology*; D004833:Epilepsy, Temporal Lobe / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012598:Sclerosis / Q000473:pathology*; D013702:Temporal Lobe / Q000473:pathology*; D055815:Young Adult
keywords: Circle of Willis; Mesial temporal sclerosis; Posterior circulation; Temporal lobe epilepsy