IMAGING FINDINGS IN PATIENTS WITH VENTRAL DURAL DEFECTS AND HERNIATION OF NEURAL TISSUE

The aim of this paper is to describe clinical and imaging findings in three patients with ventral dural defects and herniation of the spinal cord or cauda equina. The literature is reviewed and the clinical, ra diological and operative findings are compared. Three patients with ve ntral dural defects of different etiologies are presented. One patient gave a long-standing history of ankylosing spondylitis, the second pa tient presents 37 years after spinal trauma, and the third patient pre sents with spontaneous spinal cord herniation. All patients had typica lly slowly progressive neurological symptoms with multiple hospitaliza tions until diagnosis was made. Characteristic findings In postmyelogr aphic CT included a ventral or ventrolateral displacement with deforma tion of the spinal cord or the cauda equina. Sagittal MRI showed this abrupt and localized anterior deviation of the spinal cord or the caud a equina to the posterior portions of a vertebral body with or without a bony vertebral defect optimally. Additionally, due to the ventral d isplacement the spinal cord, the dorsal subarachnoid space was relativ ely enlarged without evidence of an arachnoid cyst, in all patients. M agnetic resonance imaging and postmyelographic CT can diagnose ventral dural defects with spinal cord herniation or nerve root entrapment. D ural defects must be considered in the presence of neurological sympto ms in cases of longstanding ankylosing spondylitis, late sequelae of f ractures of vertebral bodies, and without history of spinal trauma or surgery.