CTA Study of Ruptured Aneurysms of the Posterior Communicating Artery

Figure 4

PcomA development as shown by CTA is as follows: (a) Grade I is defined by the absence of the PcomA; the arrow indicates the aneurysm. (b) Grade II is defined by the presence of a thin PcomA (asterisk); the arrow indicates the aneurysm. (c–d) Grade III is defined by the presence of a thick fetal-type PcomA (asterisk); the arrow indicates the aneurysm. Abbreviations: CTA: computed tomography angiography; ICA: internal carotid artery; PCA: posterior cerebral artery; PcomA: posterior communicating artery.

(a)

(b)

(c)

(d)