Abstract
Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory disease that causes recurrent neuritis and myelitis. Ravulizumab, a complement protein C5 inhibitor, was developed to treat NMOSD. However, its efficacy in improving symptoms remains unclear. This case report describes the case of a 30-year-old woman with NMOSD who developed thoracic myelitis. Initial treatment with high-dose methylprednisolone and hemodialysis alleviated paraplegia, although urinary retention persisted. Two months after initiating ravulizumab treatment, urinary function improved. Ravulizumab administration may have contributed to the improved urinary retention.