Symptomatic cerebral vasospasm after clipping of Unruptured Intracranial Aneurysms (UIA) is extremely rare. Furthermore, its pathophysiology and risk factors are poorly understood. Delayed diagnosis and treatment can lead to severe neurological deficits. We report the case of a 53-year-old woman who developed delayed symptomatic cerebral vasospasm seven days after clipping of an unruptured left middle cerebral artery aneurysm. The patient presented with right-sided hemiparesis and motor aphasia. Digital subtraction angiography revealed vasospasms from M1 to M2 segments. Treatment with intra-arterial fasudil injection and continuous intravenous fasudil with ozagrel sodium resulted in complete neurological recovery. Cerebral vasospasm after UIA clipping is uncommon and may lead to it being overlooked, thereby resulting in serious sequelae.

Maoki Matsubara graduated from Nippon Medical School in 2018 with an MD and began working as a resident at New Tokyo Hospital. In 2020, he joined the Department of Neurosurgery at New Tokyo Hospital as medical staff. By 2023, he was employed as a clinical assistant professor in the Department of Neurosurgery at Kawasaki Medical University. In 2025, he returned to New Tokyo Hospital as medical staff, having also obtained board certification in neurosurgery and stroke medicine. He currently participates in over 200 neurosurgical procedures annually and mentors residents.