Abstract
We report a case of bypass surgery for a cerebrovascular ischemic event caused by giant cell arteritis (GCA). A 70-year-old female with transient right hemiparesis was admitted to our hospital. Diffusion-weighted imaging showed acute infarction of the left subcortical watershed areas. Magnetic resonance angiography (MRA) showed severe stenosis at the left cavernous portion of the intracranial internal carotid artery. Despite intravenous anticoagulation therapy, her right hemiparesis worsened. An emergent left superficial temporal artery-middle cerebral artery (STA-MCA) bypass was performed. The intima of the STA was markedly hypertrophic. We identified abnormal tissue and part of the STA was sent for pathological examination. After bypass surgery, the neurological findings transiently improved; however, exacerbation of the right hemiparesis and aphasia occurred on the second postoperative day. Increasing acute cerebral infarction was identified on magnetic resonance imaging, and MRA showed that the bypass was occluded. An occipital artery (OA)-MCA anastomosis was added, but the bypass occluded again. The postoperative pathologic diagnosis was GCA in both the STA and OA. Strokes associated with GCA are rare and difficult to distinguish from atherothrombotic cerebral infarction. When a donor blood vessel abnormality is observed during bypass surgery, rapid pathological diagnosis is recommended to avoid bypass failure.
