Infratentorial cerebral proliferative angiopathy: A rare entity with high risk of hemorrhage

Abstract

Background: Cerebral proliferative angiopathy (CPA) is a rare vascular disease characterized by nonfocal angiogenic activity. Numerous case reports have been published; however, despite there are a few reported cases of infratentorial CPA (or cerebellar proliferative angiopathy), no comprehensive review of this condition has been conducted.

Case description: We report two cases of infratentorial CPA, and both of them presented intracranial hemorrhage. The first case was a 48-year-old woman with an incidentally detected vascular abnormality in the cerebellum, which remained stable for 11 years before presenting with subarachnoid hemorrhage. The second case was a 5-year-old girl who presented with a sudden headache and decreased consciousness. Digital subtraction angiography was performed in both cases, but the source of hemorrhage remained unidentified, and conservative management was chosen.

Conclusion: A review of previously reported infratentorial CPA cases suggests that infratentorial CPA has a significantly higher risk of hemorrhage than supratentorial CPA. However, the risk of rebleeding appears to be low. Our findings highlight the need for further research to determine the optimal management strategies for this rare entity.

Keywords: Cerebral proliferative angiopathy; Intracranial hemorrhages; Vascular disease.

Figure 1:

(a) Initial magnetic resonance imaging (MRI) obtained when patient 1 was 48 years old revealed abnormal vascular proliferation in the left cerebellar hemisphere. The MRI also showed dilation of the draining vein into the great vein of Galen. (b) Computed tomography performed 11 years later, following a severe headache episode, revealed a subarachnoid hemorrhage. (c) MRI at the time of subarachnoid hemorrhage. Vascular structures showed no significant changes compared to the findings 11 years earlier.

Figure 2:

(a) Left vertebral angiogram revealed densely proliferated abnormal vessels throughout the left cerebellar hemisphere, draining into an enlarged great vein of Galen. No dominant feeder was identified. (b) Left external carotid angiogram demonstrated transdural supply from the occipital and middle meningeal arteries. (c) Posterior oblique view of three-dimensional rotational angiography revealed no aneurysms or dissections. Numerous abnormal vessels were observed in the left cerebellar hemisphere.

Figure 3:

(a) Initial computed tomography of patient 2 revealed a 3 cm hematoma in the left cerebellum. (b) Contrast-enhanced magnetic resonance imaging revealed extensive abnormal vascular networks within the left cerebellar parenchyma.

Figure 4:

(a) Digital subtraction angiography of patient 2 showed numerous small feeders originating from the left superior cerebellar artery and posterior inferior cerebellar artery with no identifiable dominant feeder or draining vein. (b) Three-dimensional rotational angiography was performed to identify the source of bleeding, but no clear evidence of an aneurysm or dissection was observed.