Simple pineal Cyst usually don't enlarge. Even if they enlarge, they don't cause subarachnoid hemorrhage. Subarachnoid hemorrhage is usually caused by ruptured aneurysm.
Aneurysm is an out-pouching in the weak portion of brain's blood carrying pipes( artery).
Consult a Neurosurgeon. You many require a 3D CT angiography or DSA.
Answered2017-07-11 16:09:27
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