Intracranial and Orbital Complications of Bony Lesions Involving the Anterior Skull Base and Paranasal Sinuses

Abstract

Purpose: A spectrum of conditions may be encountered in the sinonasal region and skull base composed of varying proportions of new bone and fibrous tissue such as osteomas, ossifying fibroma, fibrous dysplasia, and osteosarcoma. We present a series of 41 patients with anterior skull base bony tumors, and we focus on the cases with intracranial or orbital complications. Clinically manifested intraorbital and/or intracranial involvements are indications for surgical treatment. The purpose of this study is to describe our experience with the surgical treatment of these rare and serious manifestations of these lesions. Methods: Our cases involved the frontal sinus, orbit, and cribriform area. A retrospective analysis was done using patient's files from the hospital and the outpatient clinic, operative notes, and pre- and postoperative imaging studies. The surgical technique included an anterior frontal sinus wall door, a type A or a type B subcranial approach, and reconstruction with fascia lata, titanium mesh coated with pericranium and plates, calvarial bone grafts, and fascia sling. Results: The age of the patients was 14 to 41 (mean, 25 yrs). Fifteen of the 41 patients presented with serious intracranial or orbital complications (headaches, CSF leak, pneumocephalus, seizures or proptosis, partial ptosis, and rapid visual deterioration). Twenty were males and 21 were females. Fifteen cases were operated using a subcranial approach and in 26 cases, only the anterior wall of the frontal sinus was removed. Complete removal of the tumor was achieved in all cases and all patients are alive. Surgical complications were mostly of short duration. Conclusions: Bony lesions of the anterior skull base can have serious local clinical effects including orbital and intracranial symptomatology. Our experience shows that these lesions are resectable with generally few complications. The subcranial approach provides a wide anatomical exposure and allows the complete resection of these tumors.