特発性胸髄硬膜外血腫の1例

Spontaneous spinal epidural hematoma:case report

I．はじめに

　特発性脊髄硬膜外血腫（SSEH）は，比較的稀な疾患であり，急激に対麻痺，四肢麻痺等を生じるが，手術により良好な子後が得られるため迅速な診断と手術が要求される．近年多症例を解析した報告より，SSEHの疫学，症候，子後などは明らかになってきたが^12,17），特発例の病因に関しては不明な点が多い^5,16）．

　今回われわれは，背部痛に続いて対麻癖を呈し，緊急手術により完全回復した症例を経験し，病理組織学的に出血．源と思われる異常血管を認めたので，SSEHの病因を中心に文献的考察を加えて報告する．

We report a case of spontaneous spinal epidural hematoma (SSEH) at the upper thoracic level which accompanied an epidural vascular lesion demonstrated by histological examination.

A 62-year-old male was referred to our department, because of sudden onslaught of back pain, progressive paraparesis, and sensory disturbance below the der-matome of Th8. He had no history of a tendency to bleed, anticoagulant therapy, or trauma. There was no abnormality in the laboratory data. MRI revealed that an epidural mass at the level of dorsal T1 and T2 was compressing the spinal cord. Multilevel spondylotic change and thickened yellow ligament were also noted. Sixteen hours after the onset, we performed laminectomy at T1 and T2 and evacuated the epidural hematoma. An unusual vascular-net like tissue was found on the dura mater after removal of the hemato-ma. Postoperatively, neurological symptoms disappear-ed within three weeks. Histological appearance of the vasuclar tissue was a cluster of vessels containing a di-lated vein with partially thin wall due to lack of elastic and collagen fibers. In reviewing the literature, there are several reports describing vascular lesions, such as cavernous angioma and AVM, as possbile etiologies of SSEH. In the present case, long lasting compression of the posterior epidural venous plexus by the thick yel-low ligament might have resulted in formation of an abnormal vein which ultimately caused bleeding.