Introduction: The caroticoclinoid ligament extends from the Anterior Clinoid Process (ACP) to the Middle Clinoid Process (MCP). Occasionally, it gets ossified and forms the caroticoclinoid foramen. Anterior clinoidectomy is a common surgical procedure to treat internal carotid artery aneurysms or pituitary tumours. Abnormal ossification of the caroticoclinoid ligament may lead to intraoperative or postoperative complications as it is not normally present. Aim: To find out the incidence of ossification of the caroticoclinoid ligament in adult human skulls. Materials and Methods: This was an observational crosssectional study that included 100 dry adult human skulls collected from the Department of Anatomy, Gandhi Medical College, Secunderabad; Osmania Medical College, Hyderabad; Bhaskar Medical College, Moinabad, Telangana, India, from January 2021 to February 2023. Adult human skulls with open vault were included. All the skulls were observed and skulls damaged in the clinoid regions were excluded from the study. The skulls were observed for the presence of any ossifications of the caroticoclinoid ligaments and the observations were noted. The qualitative data was presented as number and percentage was calculated. The data was recorded in MS excel version 2021. Results: The incidence of ossification of caroticoclinoid ligament was 8 (8%). The incidence was higher on right-side when compared to the left-side. Bilateral complete ossification of the caroticoclinoid ligament was observed in 2 (2%) skulls; bilateral incomplete ossification was observed in 3 (3%) skulls, unilateral complete ossification was observed in 2 (2%) skulls on the right-side. In one skull 1 (1%), complete ossification was observed on the right-side and incomplete ossification was observed on the left-side. Conclusion: Knowledge of the ossification of the caroticoclinoid ligament is important for neurosurgeons while performing anterior clinoidectomies or skull base surgeries. Radiological confirmation of the ossification of the caroticoclinoid ligament is essential to avoid complications.

Introduction: The trigeminal nerve is principally responsible for controlling the sensory modalities of the face. The Foramen Ovale (FO) is one of the apertures present in the skull base, through which the mandibular nerve, a branch of the trigeminal nerve passes. Aim: To deliver a thorough understanding of the anatomical variations of the trigeminal ganglion and FO that would be beneficial to neurologists and neurosurgeons when performing various treatments involving these structures. Materials and Methods: The present systematic review was formulated according to Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines. Major electronic databases were screened and all types of studies including descriptive studies, surveys, full-text literature providing information about the variations in trigeminal ganglion and FO, were incorporated in the current review. Studies from 2001 to 2022 were included in this review. The risk of bias evaluation in the present study was conducted by using the review manager software (Rev Man version 5.4) and risk assessment domains were classified as high, indeterminate, or low risk. The recommended approach to check biases such as selection, performance, attrition, reporting, and other biases was done. Results: A total of 12 studies were examined. The studies measured the proper location and the size (diameter) of the trigeminal ganglion and FO using the MRI-based findings in 1,341 subjects in total. It was observed that the length of the trigeminal nerve was found to be about 9.66 mm in the cistern (range 6.04-20.74 mm) in 50% of studies, whereas in 16.67% of the studies trigeminal nerve was longer in the older patients as compared to the normal anatomy. Additionally, the distinctive form of the FO was noted in the current investigation. In total, (n=4) 66.66% of the studies demonstrated the oval shape of the FO, and (n=3) 50% of studies noticed an almond shape, 50% identified a round shape; (n=2) (33%; n=2) displayed a slit form. Only one investigation demonstrated a bony bridged of FO whereas 33% showed tubercle and triangular shapes. Conclusion: Majority of the studies showed that the length of the trigeminal nerve was found to be about 9.66 mm. Whereas, only one author reported that the trigeminal nerve is longer in the older patients as compared to the normal anatomy. The majority of studies demonstrated that the variations were observed in the shape of the FO, i.e., oval, round, almond, slit, spine.