Endoscopic skull base reconstruction of large defects: retrospective analysis of 30 cases

Abstract

Background. Endoscopic skull base reconstruction of large defects is a difficult issue in neurosurgery, as there are problems associated with a wide dural resection, intra-arachnoid dissection (due to removal of the meningocele or resection of an intracranially spreading tumor), and exposure to high-flow cerebrospinal fluid within the cisterns. But perhaps the most significant influence is the larger nonvascularized reconstructive bed – cerebrospinal fluid on one side and sinus cavity (air) on the other.The study objective is to analyze our own experience in treating patients with large defects of the skull base and, based on the results obtained, to optimize the method of reconstruction.Materials and methods. A retrospective analysis of 30 cases of reconstruction of large defects of skull base of various etiologies. The results of surgery in the early and late postoperative period were evaluated. Statistical analysis was carried out using the exact Fisher criterion and the analysis of arbitrary contingency tables using the chi-square criterion. A literature review was conducted to compare the data obtained with the results of other studies.Results. In the group of patients (n = 16) for whom reconstruction was performed only with free transplants the effectiveness of reconstruction was 75 %. In the group of patients (n = 14) who underwent the last stage of reconstruction using a vascularized pedicled nasoseptal flap, the plastic surgery efficiency was 100 %. According to statistical analysis, there is a relationship between the choice of transplant type and the multilayer technique (p <0.05). The use of lumbar drainage did not affect the recurrence of cerebrospinal fluid leak in the postoperative period (p >0.05).Conclusion. Endoscopic skull base reconstruction can be effectively used for defects of the skull base >1.5 cm. When choosing the technique of reconstruction of large defects of the skull base, preference should be given to multilayer plastic using vascularized flaps. The use of lumbar drainage for reconstruction of large defects is a justified method in the case of a clear definition of indications for its use, based on a comparison of the possible benefits and risks associated with the invasiveness of the method.