Surgical resection of a ruptured left frontal mycotic aneurysm localized with ICG angiography: a case report

Introduction and importance: Ruptured intracranial mycotic aneurysms are rare. There are no established guidelines for management. Limited case reports are available, with no randomized controlled trials. Case presentation: A 58-year-old male presented with disseminated Staphylococcus aureus bacteremia secondary to left lower limb cellulitis. Investigations revealed infective endocarditis and multiple septic emboli in the brain, spleen, and kidney. On day 17 of admission, the patient was found obtunded with global aphasia and right-sided hemiplegia. Computed tomography showed a 57 × 43 × 15 mm left frontoparietal intraparenchymal hemorrhage secondary to a ruptured 6 mm left frontal intracranial mycotic aneurysm. Digital subtraction angiography was not required, and endovascular treatment was unsuitable. The patient underwent craniotomy and resection of the mycotic aneurysm, as well as evacuation of the intraparenchymal hematoma using neuronavigation and intraoperative indocyanine green angiography (ICGA). Clinical discussion: The aneurysm was difficult to visualize under natural light despite the use of neuronavigation. ICGA provided a very detailed real-time assessment of cerebrovascular architecture and enabled accurate localization and successful resection of the mycotic aneurysm. Conclusion: ICGA is not commonly used in the surgical resection of intracranial mycotic aneurysms and should be considered if neuronavigation is inadequate for localization.