Cranial subdural hygroma complicating thoracic disc surgery. A case report.

Apersistent dural opening is one of the most frequent complications of spinal surgery. The most common cause is an inadvertent durotomy, the prevalence of which has varied notably in different studies. Previous reviews revealed that seventeen of 450 and eighty-eight of 641 patients sustained an incidental durotomy during lumbar spine surgery1,2. In the thoracic spine, dural defects are most commonly traumatic and less frequently iatrogenic. Previous accounts of thoracic dural defects have described cerebrospinal fluidpleural space fistulae leading to pleural effusion and, more rarely, to pneumocephalus3,4. In this report, we describe the case of a patient in whom the surgical treatment of two adjacent, massive, calcified thoracic disc herniations resulted in the development of bilateral cranial subdural hygroma due to a cerebrospinal fluid-pleural space fistula. This appears to be the first such report. The pathogenetic, diagnostic, and operative aspects of this case are discussed. Our patient was informed that data concerning the case would be submitted for publication. Asixty-seven-year-old man with a short history of a marked, progressive paraparesis was admitted to our institution. Magnetic resonance imaging of the spine demonstrated disc herniations at the T9-T10 and the T10-T11 levels (Fig. 1). A computed tomographic scan of the disc space at the T9-T10 level demonstrated a large, calcified central disc herniation with limited calcification inside the disc space (Fig. 2). Fig. 1 T2-weighted sagittal magnetic resonance image demonstrating large central thoracic disc herniations at the T9-T10 and T10-T11 levels, with marked ventral compression of the spinal cord. Fig. 2 Plain computed tomographic scan, demonstrating a large, calcified central disc herniation at the T9-T10 level. Limited calcification is evident within the disc space. Good operative exposure of the involved thoracic vertebrae was achieved through a standard left-sided transthoracic, transpleural approach. At this lower thoracic level, a …