Commentary

The authors report their experience with seven patients with minor skull base defects that were treated through a transmastoid approach with flexible hydroxyapatite sheets. These defects were less than 3 cm in diameter. There were no major complications, and all cerebrospinal fluid leaks and tegmental defects were treated successfully. The minimum follow-up was 18 months.

This approach represents a viable alternative for the treatment of tegmental defects. At our institution, we typically perform a middle fossa craniotomy, elevate the dura of the temporal lobe, and place a split-thickness skull graft in the defect. Depending on the size of the defect, we may place a lumbar drain. We have used a hydroxyapatite sheet for cranioplasty during closure of retrosigmoid craniotomies. After performing about 40 cases, however, we stopped using it because the hydroxyapatite sheet had eroded through the ear canal or caused infection in several patients.

The authors' recommendation to soak the product in an antibiotic solution is well taken. They should be congratulated on their innovative approach to this common problem.