Life-Threatening Hemorrhagic Moyamoya Disease: Report of Rare Case of Atraumatic Acute Subdural Hematoma Due to Ruptured Transdural Anastomosis.

BACKGROUND

Atraumatic acute subdural hematoma (ASDH) associated with moyamoya disease (MMD) is rare, and only a few studies have reported the bleeding origin. We present a case of atraumatic ASDH attributable to a transdural anastomosis that developed owing to the compensatory mechanisms involved in the pathogenesis of advanced MMD. This is the first case of life-threatening atraumatic ASDH associated with MMD in which the rupture point was clearly visualized using a 3-dimensional rotational reconstructed image.

CASE DESCRIPTION: A 37-year-old woman presented with sudden-onset, serious, atraumatic ASDH requiring emergency decompressive craniectomy. The cerebral angiograms revealed that she had advanced MMD with transdural anastomosis that was classified as Suzuki stage V with a 5-mm saccular aneurysm in the middle meningeal artery on the affected side, which was suggested as the bleeding origin. Follow-up angiograms demonstrated that the aneurysm spontaneously disappeared and was inferred to be a pseudoaneurysm. We performed a left extraintracranial bypass to prevent recurrent hemorrhage. With intensive rehabilitation, the patient accordingly achieved stroke-free survival with a modified Rankin Scale score of 3 for 1 year.

CONCLUSIONS

Atraumatic ASDH associated with MMD is a rare type of hemorrhagic MMD, and a 3-dimensional-rotational reconstructed image was useful to confirm the origin of the bleeding. The transdural anastomosis development most likely correlates with the occurrence of any type of hemorrhagic MMD. We should consider that the transdural anastomosis collapse can cause a life-threatening atraumatic ASDH and should plan a surgical strategy carefully so as not to destroy collateral supply through the transdural anastomosis in such cases.