Severe reversible cerebral vasoconstriction syndrome mimicking aneurysmal rupture and vasospasm

Introduction: Presenting symptoms of aneurysmal subarachnoid hemorrhage (SAH) and reversible cerebral vasoconstriction syndrome (RCVS) may overlap. Patients with RCVS often harbor unruptured aneurysms. Summary of Case: We report a case of RCVS in a patient with an unruptured intracranial aneurysm. The development of diffuse vasoconstriction after aneursym clipping in the absence of any subarachnoid blood was initially confusing, until subtle vasoconstriction before clipping was seen retrospectively. Results: We obtained perfusion and diffusion MRI studies on this patient, which shed light on the pathophysiology of RCVS. Conclusion: It is important for physicians who care for patients with aneurysmal SAH to recognize RCVS, as the treatments for these two conditions are different.