Post-traumatic syringomyelia

The improvement of preclinical emergency medicine, better surgical and cons ervative therapies, and the development of intensive care units and special ized centers have improved the survival rate for patients with serious spin al cord injuries. Therefore, more sequelae of chronic spinal cord injuries such as post-traumatic spinal cord cavitations also occur. The first such c ase was described by Bastian in 1867. Generally, these cavitations were dia gnosed from 2 months up to 32 years after the trauma. The overall prevalenc e of post-traumatic syringomyelia (PTS) is not known; however, with the inc reasing use of magnetic resonance imaging (MRI), its diagnosis has increase d, ranging from 2.3% of paraplegic and tetraplegic patients in 1976 and 3.2 % in 1985, to nearly 50 % in a selected group of patients in 1991 and 1993. In 1995, a 4.45 % incidence was reported. In our clinic we are currently t reating 440 cases of syringomyelia, 140 of which are PTS. Several observati ons suggest more than one potential mechanism for the evolution of a post-t raumatic cyst or PTS. Various factors, such as hemorrhage or, in particular , ischemia within the spinal cord, blockage of the cerebrospinal fluid (CSF ) pathways around the cord or localized meningeal fibrosis either alone or in combination with other factors, may be involved. Clinically, sensory dis turbances, loss of motor function, pain, and modification of the deep tendo n reflexes are observed in most patients. On MRI, PTS is seen as a longitud inal, cystic cavity within the spinal cord, giving a hypointense signal on T-1-weighted images and a hyperintense signal on T-2-weighted images. For t reatment planning it is mandatory to identify the lower and upper end of th e PTS on the MRI.