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.

The effectiveness of poloxamer 407-based new anti-adhesive material in a laminectomy model in rats

“…Oh et al [33] reported that poloxamer is a good anti-adhesive agent playing the barrier's role appropriately, because it showed fairly good anti-adhesion effects, had small inflammatory reaction and non-toxicity within the body in a study using the peritoneum adhesion model in rats. Reigel et al [34] also said that the substance had about 50% of anti-adhesion effects in an experimental study using the laminectomy model in rabbits, affirming that poloxamer is a useful anti-adhesive agent in spine surgery. This study also found that the new material successfully prevented grade 1 or higher degrees of adhesion in all comparisons between the experimental and negative control group.…”

In situ gel forming systems of poloxamer 407 and hydroxypropyl cellulose or hydroxypropyl methyl cellulose mixtures for controlled delivery of vancomycin

“…[3][4][5][6][7] In addition, P407 exhibits non specific antiadhesive properties that can prevent the adherence of proteins and bacteria, and thereby hinder infections. [8][9][10] Aqueous solutions of P407 above a concentrations of about 20% (w/w) are liquid when refrigerated, but gel upon warming. 11 However, application of concentrated polymer solutions (>16%) in drug delivery may be disadvantageous as it changes the osmolality of the formulation, kinetics of gelation, and causes discomfort in ophthalmic applications due to vision blurring and crusting.…”

Control of Staphylococcal Adhesion to Polymethylmethacrylate and Enhancement of Susceptibility to Antibiotics by Poloxamer 407

“…The prevention of fibrinogen adsorption and platelet adhesion to surfaces (1,17) could be useful in the prevention of medical-implant infection. These poloxamers also prevent postsurgical tissue adhesion (4,24).…”