Accuracy of CT angiography in the assessment of a fetal origin of the posterior cerebral artery

Abstract

An uncommon cause of cerebral ischemia in the territory of the posterior cerebral artery (PCA) is the combination of a fetal origin of the PCA and atherosclerotic disease in the internal carotid artery. This study compared the accuracy of CTA with DSA in the assessment of a fetal origin of the PCA. Patients in whom an intracranial DSA and CTA had been performed were reviewed. A fetal origin was defined as a normal-sized patent posterior communicating artery (PCoA) with hypoplasia or aplasia of the ipsilateral P1 segment. One hundred PCAs in 51 patients were analyzed. A fetal origin was present in ten vessels (10%, eight patients). CTA revealed all of them. CTA considered an additional three vessels as having a fetal origin, while DSA revealed a PCoA with the same diameter as the P1 segment of the PCA. Sensitivity and specificity of CTA in the assessment of a fetal origin could be estimated at 100 and 97%, respectively. Positive and negative predictive values were 77 and 100%, respectively. CTA can be considered a valid diagnostic tool for the assessment of a fetal origin of the PCA in patients with a cerebral ischemic event in the territory of the PCA.

Prospective, multireader evaluation of image quality and vascular delineation of multislice CT angiography of the brain

“…However, even the small arterial vessels could be reliably delineated and discerned by our readers. This is in accordance with a recently published study that demonstrated the accuracy of CT angiography in discerning a fetal origin of the posterior artery as a potential thrombo-embolic pathway [19]. The relatively poor score of the cavernous sinus and the C2 segment of the ICA is probably due to the close topographical proximity to the osseous structures of the skull base and constitutes a typical limitation of CT angiography.…”

Configurations of the circle of Willis: a computed tomography angiography based study on a Polish population

“…Preserving techniques may also influence the caliber of vessels [4,13]. Additionally, external mea- The studies confirm that CTA is an accurate imaging technique for the evaluation of the structures of the CW [7,16]. It is highly sensitive and specific, except when it comes to detecting hypoplastic segments, where it has a rather low sensitivity [7].…”

“…It is highly sensitive and specific, except when it comes to detecting hypoplastic segments, where it has a rather low sensitivity [7]. Additionally, CTA allows for exact assessment of the presence of the foetal configuration of the posterior part of the circle [16]. The main limitations of this study correspond to those of imaging techniques in general and particularly to limitations of CTA.…”

“…Cadaveric studies are still widely performed [4,5,11,15] and several imaging methods, including transcranial colour-coded duplex ultrasonography (TCCD) [9], 3-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) [2,3,14], and computed tomography angiography (CTA) [2,7,13,16] have been used to examine the circle. These imaging techniques have allowed for the precise depiction of the clinically relevant collaterals of the circle by assessing the patency of blood vessels that determine the circle's physiological completeness.…”

Anatomic Variations in the Circle of Willis in Patients with Symptomatic Carotid Artery Stenosis Assessed with Multidetector Row CT Angiography

“…Selective visualization of 1 artery may hinder a fair interpretation in digital subtraction angiography due to the injection pressure, the absence of a temporal window hampers transcranial Doppler use in approximately 25% of patients, and flow-based magnetic resonance angiography techniques may not visualize nonfunctional but patent arterial segments. Multidetector row CT scanning allows consistent imaging of intracerebral arteries together with the carotid and vertebral arteries and thereby represents an excellent tool for imaging the anatomy of the circle of Willis [25]. …”