Introduction: Sacral and presacral schwannomas are rare and account for a minority of spinal schwannomas. We aim to present our institution's experience surgically treating sacral schwannomas over twenty-one years. Additionally, we assess the literature for surgical cases of sacral schwannomas to compare tumor characteristics and outcomes following resection.Methods: Data on demographics, presenting symptoms, lesion characteristics, surgical management, and outcomes were collected for 27 patients treated surgically for sacral or presacral schwannoma between 1997 and 2018 at all Mayo Clinic locations and compared to those of patients found in the literature.Results: We identi ed 31 studies in the literature containing 93 patients with sacral schwannoma treated surgically. Our patients and those in the literature experienced similar symptoms, with the most common symptom being pain and the least common being sexual dysfunction, and age at diagnosis. Most of our patients (59.3%) reported full recovery from preoperative symptoms, while a minority reported a partial recovery (33.3%) and no recovery (11.1%). A smaller percentage of patients found in the literature experienced full recovery (31.9%) and partial recovery (29.8%) but also no recovery (1.1%). Our patients experienced fewer complications (14.8% versus 25.5%). Conclusion:Outcomes of patients with sacral or presacral schwannomas vary based on patient demographics, tumor characteristics, symptoms, and surgical treatment. Among the range of symptoms experienced by these patients, the most common is pain. Prognosis improves and overall survival rate is high when the surgical approach towards sacral schwannomas is prepared and executed appropriately.

BACKGROUND:The lingual process of the sphenoid bone (LP) and the petrolingual ligament (PLL) surround laterally the internal carotid artery within the middle cranial fossa (MCF). OBJECTIVE: To study the LP and the PLL and anatomical variations considering their relationships with different structures and landmarks within the MCF, especially oriented toward the endoscopic endonasal approaches. METHODS: Seventy-two sides of dry skulls and 20 sides of embalmed specimens were studied. The measurements of the LP and the PLL were obtained, considering important landmarks in the MCF. RESULTS: The LP had a mean length and height of 5 mm and 3 mm, respectively. Its distance from the foramen lacerum was 6 mm, from the foramen ovale 10 mm, foramen rotundum 15 mm, and petrous apex 9 mm. In 44 sides (61.11%), the LP partially closed the lateral aspect of the carotid sulcus; in 17 sides (23.61%), it was found as a near-ring; and in 11 sides (15.2%), it was considered rudimentary. Considering the PLL, its length and height were, respectively, 9 mm, and 4 mm. CONCLUSION: The LP and PLL separate the carotid artery at the inferior aspect of Meckel's cave and constitute important landmarks for endoscopic endonasal approaches to Meckel's cave and MCF, and their identification and removal is essential for internal carotid artery mobilization in this area.