2007 年 20 巻 1 号 p. 13-15
Recently, intraoperative ultrasonography has been becoming increasingly useful for evaluation and monitoring of surgical procedures during spinal cord decompression. We evaluated the degree of decompression and fluid circulation around the cord using ultrasonography during laminoplasty. Laminoplasty was performed by vertical division of the spinous process (Kurokawa method). Intraoperative ultrasonography was performed using an Aplio instrument(Toshiba Medical) with a 6.5 MHz transducer. Spinal decompression was evaluated by delineation of the spinal cord, the subarachnoid space or the shape of the osteophyte, and dynamic imaging of the cerebrospinal fluid and blood flow in the epidural venous plexus with the pulse Doppler method. Intraoperative ultrasonography was performed for 5 patients with cervical myelopathy. This revealed the ventral and dorsal subarachnoid space as well as pulsatile movement of the spinal cord in all 5 patients after satisfactory cord decompression. The flow velocity of the cerebrospinal fluid around the spinal cord measured 1.5-3.0cm/ in 2 patients, and that in the epidural venous plexus measured 5.0-10.0cm/s in 3 patients. This improved circulation was considered to have been due to the spinal cord decompression, and the preoperative symptoms were ameliorated in all patients. Intraoperative ultrasonography is considered useful for real-time evaluation of spinal cord decompression during laminoplasty for cervical myelopathy.