Presentation
Headache
Patient Data
Age: 40 years
From the case:
Colloid cyst with anterior communicating artery aneurysm
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- oval hyperdense mass at foramen of Monro consistent with a small colloid cyst
- old lacunar infarction of left frontal lobe
- vague hyperdensity along the inferior longitudinal superior fissure, near the superior temporal gyrus, is suspected to represent an anterior communicating artery (ACOM) aneurysm
From the case:
Colloid cyst with anterior communicating artery aneurysm
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MRI/MRA confirmed the CT findings of left ACOM aneurysm.
Mass at the foramen of Monro is T1 isointense / T2 hypointense and non-enhancing, consistent with colloid cyst.
Again noted, the old lacuna infarction in the left anterior corona radiate with encephalomalacia.
Case Discussion
- it is important to exclude hydrocephalus in any case of colloid cyst
- in ACOM aneurysm rupture, subarachnoid hemorrhage will be highest in the anterior interhemispheric fissure
- time-of-flight MRA is 85-95% sensitive for aneurysms ≥3 mm