Iatrogenic Pseudoaneurysm at the Deep Temporal Artery after Fronto-temporal Craniotomy Manifesting as Repeated Subcutaneous Hemorrhage -Case Report

Iatrogenic pseudoaneurysm formation at the deep temporal artery (DTA) is a rare complication after neurosurgical intervention by craniotomy, and its management strategy has yet to be determined. We report a patient who developed iatrogenic pseudoaneurysm at the DTA after fronto-temporal craniotomy manifesting as repeated subcutaneous hemorrhage. A 44-year-old man underwent standard fronto-temporal craniotomy for the microsurgical clipping of a ruptured anterior communicating artery aneurysm in the acute stage. The initial postoperative course was uneventful, but he developed a massive subcutaneous hematoma that penetrated the surgical wound, leading to hypovolemic shock 23 days after the aneurysm surgery. Due to the continuous hemorrhage after temporary hemostasis by ligation of the superficial temporal artery, he underwent catheter angiography, which revealed a newly-formed pseudoaneurysm at the DTA that was 16 mm in diameter. Neuroendovascular obliteration of the pseudoaneurysm was successfully performed using liquid embolization material, n-butyl-2-cyanoacrylate, under local anesthesia. Pseudoaneurysm at the DTA is a rare but possible complication after fronto-temporal craniotomy, which can be fatal due to marked hemorrhage. Due to the anatomically deep location of the DTA under the temporal muscle, we recommend accurate diagnosis of the pseudoaneurysm by catheter angiography and prompt obliteration of the affected vessel by a neuroendovascular procedure under local anesthesia, especially when the hemodynamic status is unstable.