A pilot investigation of poloxamer 407 for the prevention of leptomeningeal adhesions in the rabbit.

Abstract

Leptomeningeal adhesion formation frequently complicates operations and diseases of the central nervous system. Chronic adhesive arachnoiditis may follow intraspinal surgery for disc, tumor, and closure of myelomeningocele, eventually producing pain and declining neurological status of the patient. Reoperation for scar removal is seldom successful as the arachnoidal adhesions reform. Poloxamer 407 (P407) has been shown to reduce postoperative peritoneal adhesion formation in rats and golden hamsters. In a rabbit model, we investigated the potential of P407 to prevent the production of arachnoidal adhesions and nerve root scarring following laminectomy and surgical meningeal injury. The lumbar spinal roots of 8 New Zealand white rabbits were surgically isolated under magnification. One root sleeve axilla was opened and immediately closed with 10-0 suture (control site) and a second root sleeve axilla was opened, P407 injected, and closed with 10-0 suture (treatment site). Five of 7 rabbits treated with P407 and followed for 7-42 days showed no arachnoidal adhesions at the level of the nerve root. Four New Zealand white rabbits had the lamina removed, and the dura over the spinal cord was opened at two sites separated by one to two lumbar segments. At one site P407 was inserted beneath the dura following durotomy, and the other site was opened in a similar fashion and immediately closed without the insertion of P407. There was a 50% reduction in leptomeningeal adhesion formation with the use of P407. P407 may be useful in neurosurgery for the prevention of arachnoidal adhesions.