Assessment of the Circle of Willis with Cranial Tomography Angiography.
BACKGROUND
The circle of Willis is a major collateral pathway important in ischemic conditions. The aim of our study was to assess the structural characteristics of the circle of Willis within the Turkish adult population, along with variations and arteries involved in the measurement of diameters and lengths on cranial computed tomography angiography (CTA).


METHODS
One hundred adult patients who underwent CTA images were evaluated retrospectively.


RESULTS
Results of the study revealed 82% adult, 17% fetal, and 1% transitional configurations. A complete polygonal structure was observed in 28% of cases. Variations of the circle of Willis were more common in the posterior portion. Hypoplasia was found to be the most common variation and was observed as a maximum in the posterior communicating artery (AComP).


CONCLUSIONS
The patency and size of arteries in the circle of Willis are important in occlusive cerebrovascular diseases and cerebrovascular surgery. Although CTA is an easily accessible non-invasive clinical method for demonstrating the vascular structure, CTA should be evaluated taking into account image resolution quality and difficulties in the identification of small vessels.
Department of Neurosurgery, Izmir Katip Celebi University Ataturk Education and Research Hospital, Izmir, Turkey.
Ayse
A
Karatas
Department of Neurosurgery, Bozyaka Education and Research Hospital, Izmir, Turkey.
Gokmen
G
Coban
Department of Radiology, Ege University School of Medicine, Izmir, Turkey.
Celal
C
Cinar
Department of Radiology, Ege University School of Medicine, Izmir, Turkey.
Ismail
I
Oran
Department of Anatomy, Ankara University School of Medicine, Ankara, Turkey.
Aysun
A
Uz
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography; D002536:Cerebral Arteries / Q000473:pathology; D002941:Circle of Willis / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014421:Turkey; D055815:Young Adult