Postoperative brainstem cavernous hemangioma complicated with LGI1 encephalitis and hypertrophic olivary degeneration: A case report and literature review

Background: This article reports the case of a patient with postoperative brainstem cavernous hemangioma complicated with anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis and hypertrophic olivary degeneration (HOD) to raise awareness of clinicians regarding LGI1 encephalitis and HOD. Case presentation We retrospectively analyzed the case data of a young male admitted to our hospital in 2022, with complaints of recurrent dizziness and headache. Based on the findings of craniocerebral computed tomography, the patient was diagnosed to have brainstem cavernous hemangioma, and he underwent surgical resection of the tumor. He subsequently developed unexplained abnormal mental behavior 1 month after the surgery. Laboratory examination revealed a positive result for anti-LGI1 antibodies in the serum and cerebrospinal fluid. Electroencephalography showed slow wave alterations in the right occipital lobe and the mesial and posterior temporal lobes. These findings confirmed the diagnosis of LGI1 encephalitis. The patient underwent immunotherapy and symptomatic treatment, and his health significantly improved. Six months later, cranial MRI showed HOD. Conclusions: The complication of brainstem cavernous hemangioma with LGI1 encephalitis and HOD after surgical resection is an extremely rare case, and a complex mechanism underlies the occurrence of this complication. Hence, clinicians must focus on early detection and treatment of this complication to achieve a better patient prognosis.