Computed Tomography Angiography Recognition of a Hemorrhagic Moyamoya Pattern May Alter Acute Blood Pressure Management.

Moyamoya disease (MMD) is a rare progressive cerebrovascular occlusive disorder characterized by stenosis of the terminal internal carotid arteries and the development of fragile lenticulostriate collateral vessels. In adults, MMD can manifest as intracranial hemorrhage (ICH), carrying significant morbidity and a high risk of recurrent bleeding. When hemorrhagic MMD coexists with bilateral large vessel occlusion, acute management becomes exceptionally complex, as the standard imperative to aggressively lower blood pressure following ICH directly conflicts with the hemodynamic requirements of collateral-dependent cerebral perfusion. A 52-year-old Caucasian woman with hypertension and treated hypothyroidism, recently started on aspirin for TIA-like symptoms, presented with acute-onset left hemiplegia and a National Institutes of Health Stroke Scale (NIHSS) score of 11. Hypertension was her sole conventional atherosclerotic risk factor, and thyroid autoantibodies obtained previously had been negative. Non-contrast computed tomography (CT) identified a 2.3 × 1.9 × 2.5 cm right gangliocapsular intraparenchymal hemorrhage with a concurrent small right thalamic hemorrhage. Computed tomography angiography (CTA) demonstrated bilateral M1 segment occlusions with distal M2 reconstitution, a pattern that immediately raised concern for MMD and led directly to the recognition that mechanical thrombectomy was not indicated. The neurosurgical team concurred with a clinical and radiographic diagnosis of moyamoya vasculopathy on hospital day two. Rather than applying standard post-ICH targets, the team individualized blood pressure management to a permissive systolic range of 120 to 160 mmHg, chosen to balance limiting hematoma expansion against preserving collateral-dependent perfusion. Intravenous nicardipine was successfully weaned by hospital day three. The diagnosis was considered probable and imaging-based. Formal cerebral angiography for Suzuki staging and revascularization planning was appropriately deferred during the acute admission and planned on an outpatient basis; the patient was discharged to an inpatient rehabilitation facility on hospital day five but was subsequently lost to follow-up, so digital subtraction angiography (DSA) was never performed. Bilateral M1 occlusion with distal M2 reconstitution on CTA in the setting of gangliocapsular hemorrhage should raise suspicion for MMD and may inform both interventional and hemodynamic decision-making. Recognition of the characteristic CTA pattern supported the decision not to pursue mechanical thrombectomy and prompted individualized blood pressure targets to preserve collateral-dependent cerebral perfusion. Because DSA was not obtained, intracranial atherosclerosis could not be formally excluded, and the diagnosis remains probable rather than definitive.