Duraplasty with freeze-dried cadaveric dura versus occipital pericranium for Chiari type I malformation: comparative study.

During the period from October 1, 1989 to October 1, 1995 a total of 26 cases of Chiari type I malformation not associated with syringomyelia were attended in our Hospital. All patients underwent cranio-cervical decompression, with occipital craniectomy and removal of the posterior arch of C1. In 3/26 (11.5%) cases an additional C2 laminectomy had to be performed and in 1/26 (3.8%) case the C3 laminae were also removed. A first group of 13 patients underwent dural repair with freeze-dried cadaveric dura sutured with continuous 4-0 Vicryl running stitches, reinforced with fibrin sealant (Tissucol). A second group of 13 patients underwent duraplasty with autogenous occipital pericranium also sutured with continuous 4-0 Vycril but no fibrin sealant at all was added. In the first group, in which freeze-dried cadaveric dura plus Tissucol was used, there were 2/13 (15.3%) cases of CSF leak, requiring some additional skin stitches to stop the leak. In 5/13 (38.4%) cases there were notorious subcutaneous CSF accumulations that required repeated punctures plus compressive bandage. In 6/13 (46.1%) pseudomeningoceles appeared that took a year to clear completely. In the 13 patients who underwent dural repair with autogenous occipital pericranium watertight closure was achieved with sutures only, no fibrin sealant was added at all. Neither CSF leaks through the wound nor subcutaneous CSF accumulations were noted. We conclude that, in our hands, autologous pericranium taken from the occipital area, gives better results than freeze-dried cadaveric dura mater in duraplasty for surgical repair of Chiari type I malformation.