Dural bridge sutures to prevent sinking of dural substitutes: technical note

Safety and Efficacy of a Novel, Self-Adhering Dural Substitute in a Canine Supratentorial Durotomy Model

BACKGROUND

Cerebrospinal fluid (CSF) leaks increase postoperative risk for complication, likelihood of reoperation, and costs.

OBJECTIVE

To investigate a novel, self-adhering polyethylene glycol-coated collagen pad (PCC) as a dural substitute relative to Duragen XS (DGX; Integra LifeSciences Corporation, Plainsboro, New Jersey) and as a dural sealant relative to Tachosil (Takeda Austria GmbH, Linz, Austria), a fibrinogen and thrombin-coated collagen pad (FTC).

METHODS

A canine supratentorial durotomy surgical model was used to investigate the safety and efficacy of PCC. For safety, 4 animals were bilaterally treated with DGX or PCC and recovered for 1, 8, or 16 wk; total 24 animals. Each animal underwent physical and neurological examinations weekly and 16-wk animals underwent a magnetic resonance imaging (MRI) examination at each time point. For efficacy, 9 animals were unilaterally treated with FTC or PCC and underwent a burst pressure test intraoperatively or 14 d postoperatively; total 36 animals.

RESULTS

In the safety study, no abnormal clinical signs or changes were noted on physical and neurological examinations, or in clinical pathology, CSF analysis or histopathology of DGX or PCC-treated animals. No consistent signs of cerebral compression, CSF leak, hemorrhage, or hydrocephalus were noted on MRI. In the efficacy study, no significant difference was found between FTC and PCC at each time point or overall (13.9 vs 12.3 mm Hg, n = 18 per group, P = .46).

CONCLUSION

PCC is safe for use as a dural substitute and effective as a dural sealant. The novel, self-adhering combination of a polyethylene glycol-based sealant and a collagen pad may offer unique benefits to the advancement of duraplasty.

Capsule formation can make secondary reconstruction of the dura mater unnecessary after cranial infection

PURPOSE

Defects of the dura mater caused by surgical intervention are often reconstructed using artificial substitutes such as polytetrafluoroethylene membrane (Gore-Tex in commercial name). In cases where secondary infection develops after the initial operation, the artificial substitute used in the primary surgery needs to be removed, and the cranial defect should be covered with tissues abundant in blood supply. The present study discusses the necessity of secondary reconstruction of the dural defect in the recovery operation.

METHODS

A retrospective study was conducted on 12 patients in whom artificial substitute was exposed because of necrosis of the overlying tissues due to infection or radiation. In recovery operations, the artificial substitute was removed, and the conditions of the underlying defects were evaluated.

RESULTS

In all cases, capsule formation had developed to cover dural defects underneath the infected artificial substitutes. The capsules were transparent and watertight, presenting no leakage of cerebrospinal fluid. After coverage of the defect regions using free-flap transfer, no patient developed postoperative complications in follow-up periods of at least 6 months.

CONCLUSIONS

Capsule formation occurs under artificial substitutes after replacement of the dura mater. Because the capsules retain the cerebrospinal fluid, replacement of the artificial materials is unnecessary in the secondary operation.