Bilateral subdural hygromas after endovascular coiling for ruptured aneurysmal subarachnoid hemorrhage: an unusual and rare complication

Subarachnoid hemorrhage (SAH) with subdural hygroma (SH) was rarely reported after endovascular coiling. A 60-year-old male presented with impaired consciousness and convulsions due to SAH from a ruptured aneurysm. It was managed by endovascular coiling 20 h after the onset of symptoms. Serial brain imaging for 2 weeks revealed progressive bilateral SHs, more on contralateral side of leaking aneurysm. Management of SH was discussed in a multidisciplinary setting to be conservative as there was neither significant mass effect nor hydrocephalus. The patient recovered neurologically except for mild dysarthria. The SH persisted for 2 months and then cleared gradually. We concluded that SH may arise and become symptomatic as an unusual sequela of post-coiling of a ruptured intracranial aneurysm, in which the SH can complicate the clinical course of SAH. However, the symptomatic SH may resolve spontaneously and completely without any intervention, but needs meticulous neurological assessment and follow-up.