Presentation
Altered sensation left upper limb.
Patient Data
Contrast studies were not performed because of previous thyroid disorder and planned contrast-enhanced MRI and MRA will follow.
There is a hyperdense lesion in the right middle cerebellar peduncle with surrounding hypoattenuation extending into the right cerebellar hemisphere and pons.
A small speck of calcification is situated immediately posteroinferior to the hyperdense lesion. There is associated mass effect, with expansion of the right middle cerebellar peduncle and partial effacement of the fourth ventricle. No hydrocephalus.
A tubular, serpiginous hyperdense structure coursing through the right cerebellopontine angle cistern and along the inferior margin of the lesion is in keeping with a prominent vessel.
A hyperdense mass adjacent to right anterior clinoid process.
No further intracranial hemorrhage detected. No evidence of acute ischemia. No calvarial abnormality. The imaged paranasal sinuses and mastoid air cells are clear.
Conclusion:
Right middle cerebellar peduncle hemorrhage is favored to represent hemorrhage due to an underlying AVM/AVF or cavernous malformation. Less likely differential diagnoses include hemorrhagic metastasis or hypertensive hemorrhage. Suspect Right ICA aneurysm adjacent to anterior clinoid. MRI/MRA is recommended for further evaluation.
There is a right middle cerebellar peduncle mass lesion with moderate surrounding FLAIR abnormality indicating vasogenic edema and significant T2* shortening on the GRE and EPI images, consistent with hemorrhage, concordant with the CT findings.
This lesion is associated with a relatively large developmental venous anomaly, with "caput medusa" within the right cerebellar hemisphere and superiorly into the pons; exiting from the right cerebellopontine angle and draining into the right superior/inferior petrosal and cavernous sinus confluence.
On the background of hypoplastic left A1 and P1, MRA demonstrates a large right-sided paraclinoid aneurysm, pointing anterolaterally. The aneurysm neck is likely situated over the carotico-ophthalmic segment, with the aneurysm configuration appearing bilobed. The less likely possibility is two aneurysms very closely located.
No convincing further abnormalities identified.
Conclusion:
The findings are most consistent with a hemorrhage into right cerebellar/cerebellar peduncle cavernoma, associated with a relatively large DVA.
Note also made of an incidental right caroticophthalmic aneurysm.
Large bi-lobed right ICA transitional but at least partially intradural aneurysm, laterally pointing. Broad necked, measuring up to 9mm. Fusiform involvement of the parent vessel. Immediately distal to the ophthalmic artery.
Large right cerebellar developmental venous anomaly (DVA) draining into the basilar plexus.
No evidence of posterior fossa aneurysm.
Conclusion:
The findings are entirely in keeping with a right cerebellar cavernoma.
Incidental right ICA aneurysm, which could be amenable to flow diverting stent, however, this would require dual anti-platelets. .
A 4 x 20 mm Pipeline Embolization Device (PED) deployed across the aneurysm neck.