Subcranial transnasal repair with free autologous grafts by the combined overlay and underlay techniques using the endoscope or surgical microscope is a safe and successful method of treating CSF leaks, provided that the CSF leak is precisely located and the site can be reached with the endoscope or surgical microscope.

The production of collagenase and collagenase inhibitor (TIMP) by various intracranial tumors (25 meningiomas, eight gliomas, seven metastases, four pituitary adenomas, and five others) was studied in short-term organ culture. While meningiomas produced negligible amounts of collagenase, two metastatic carcinomas of bronchial and breast origin produced significant amounts of the enzyme. Cultures of dura from an invasive meningioma and of bone invaded by a meningioma also produced collagenase. In varying amounts, TIMP was detected in culture media from most of the tumors studied; invasive tumors tended to produce less TIMP than noninvasive tumors. The results are discussed in relation to current views on tissue degradation and mechanisms of tumor invasion.

Objective: To study the long-term outcome of endonasal endoscopic skull base reconstruction with nasal turbinate tissue free graft. Patients and Methods: This study included 55 consecutive patients who underwent endonasal endoscopic skull base reconstruction with nasal turbinate graft and were available for follow-up. They were 30 patients with pituitary adenomas, 20 with cerebrospinal fluid (CSF) rhinorrhea of different etiologies, three with meningoencephalocele, and two with skull base meningiomas. Autologous nasal turbinate tissue materials were used in reconstructing the skull base defect. Clinical follow-up with endoscopic nasal examination was done routinely 1, 3, 6, and 12 months after surgery. Computed tomography and magnetic resonance imaging were performed when indicated. The follow-up period ranged from 6 months to 8 years. Results: There were no major operative or postoperative complications. Nasal turbinate graft was effective in sealing of intraoperative CSF leak, obliteration of dead space, and anatomic reconstruction of the skull base. There was no evidence of graft migration or inflammatory changes. Starting from 3 months after surgery to the rest of the follow-up period, endonasal endoscopic view of the site of duraplasty showed that: with small skull base defect (less than 5 mm), there was neither dural pulsation nor prolapse; with moderate-sized defect (5 to 10 mm), there was dural pulsation without prolapse; with larger defect (> 10 mm), there was dural pulsation and prolapse. These finding were constant regardless of the etiology of the lesion and the reconstruction material used. Conclusions: This long-term study demonstrated the efficacy of nasal turbinate graft in sealing of CSF leak without any delayed complications. Other rigid materials may be considered in reconstruction of large skull base defect (more than 10 mm) to prevent dural prolapse and herniation. For any future endonasal procedure for those patients, who had previous endonasal

Objective: To demonstrate the flexibility, adaptability, and efficacy of endoscopic endonasal removal of the inferior half of the middle turbinate in a cadaveric study and in surgery for the treatment of different sphenoid sinus and skull base lesions. Methods: Anatomic Cadaveric Study: Five adult cadaveric heads were studied. Six nostrils of 3 cadavers were studied endoscopically after the lower half of the middle turbinate was removed. Two adult cadaveric heads underwent bilateral paraseptal sagittal sectioning and were studied after the lower half of the middle turbinate was removed. Sixty-five patients with different sphenoid sinus and skull base-related lesions were treated through this surgical approach. Results: This approach increased surgical exposure, decreased tubular vision, and offered wider anatomic panoramic orientation with 0-degree and angled endoscopes. In the surgical group, there were no major intra-or postoperative complications. The approach improved exposure, accessibility to the lesion, and permitted good hemostasis, tumor resection, and repair of the skull base defect. Conclusion:The current approach provides a wide surgical field without increasing morbidity. It avoids unnecessary trauma to the other nostril as occurs in a binostril approach. The harvested piece of turbinate tissue is an excellent source of donor material for

No abstract