The patient expired the next day due to compression of his brainstem. Patients who survive strokes show disturbed learning profiles and psychoemotional problems. Children perform poorly in school relative to their peers. Neovascularization occurs in the areas of the brain that are left underperfused by the stroke. The network of vessels in moyamoya have a propensity to rupture.
Hemorrhage produces additional neurological deficits.
The problem frequently is complicated by pre-existing defalcations from the earlier arterial occlusive stroke. Bleeds from moyamoya can be extremely debilitating and even fatal in patients with sickle cell disease. Another late complication of arterial occlusive stroke in patients with sickle cell disease is aneurysm in the contralateral circulation. Neural tissue in the region of the brain whose blood flow is compromised by the stroke often remains viable due to blood flow up the contralateral circulation and between the cerebral hemispheres by the Circle of Willis. Aneurysms can develop due to the increase in blood flow rate and arterial wall pressure.