The "candy wrapper" of the pituitary gland: a road map to the parasellar ligaments and the medial wall of the cavernous sinus

How I do it: Endoscopic endonasal resection of the medial wall of the cavernous sinus

BACKGROUND

Resection of the medial wall of the cavernous sinus (MWCSR) is a growing surgical maneuver for the radical removal of pituitary adenomas.

METHOD

We present a simple modification of the technique following the two dural layers of the floor of the sella turcica, allowing for early identification of the medial wall and simplifying dissection. We support this technique with an anatomical analysis on cadaveric specimens and clarifying dissection images.

CONCLUSION

Recognition and dissection of the dural unfolding of the floor of the sella turcica are "key points" that lower the risk and facilitate the MWCSR.

The Coexistence of Carotico-Clinoid Foramen and Interclinoidal Osseous Bridge: An Anatomo-Radiological Study With Surgical Implications

BACKGROUND AND OBJECTIVES

The coexistence of complete carotico-clinoid bridge (CCB), an ossification between the anterior (ACP) and the middle clinoid (MCP), and an interclinoidal osseous bridge (ICB), between the ACP and the posterior clinoid (PCP), represents an uncommonly reported anatomic variant. If not adequately recognized, osseous bridges may complicate open or endoscopic surgery, along with the pneumatization of the ACP, especially when performing anterior or middle clinoidectomies.

METHODS

According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews guidelines, a systematic scoping review was conducted up to June 5, 2023. PubMed, Scopus, Web of Science databases, and additional citations were searched. Two hundred high-resolution noncontrast computed tomography (CT) scans (400 sides) and 41 dry skulls (82 sides) were analyzed to identify the different morphology of sellar bridges, focusing on the coexistence of complete CCF and ICB. Two embalmed latex-injected heads with coexisting CCF and ICB were dissected step-by-step to show the anatomic relationship with the surrounding structures from an endoscopic and microscopic perspective.

RESULTS

A total of 19 articles were included. The review identified a complete CCF and ICB rate ranging from 4.92% to 6.3%. The analysis of 200 CT scans revealed a rate of coexistence in 4% of the cases, all encountered in White women. Two different types of interclinoid bridges were identified based on the degree of bone mineralization. Both endoscopic and macroscopic step-by-step dissections highlighted variability in morphology and consistency of the sellar bridges and the close relationship with the cavernous sinus neurovascular structures.

CONCLUSION

The coexistence of CCF and ICB is an anatomic variation found in 4% of cases. Preoperative knowledge of the degree of mineralization and its relationship with surrounding structures is essential to performing safe surgery and minimizing cranial nerve and vascular injuries. Preoperative high-resolution CT scans can adequately identify these anatomic variations.

Anatomy of the medial wall of the cavernous sinus: A systematic review of the literature

The existence, composition, and continuity of the medial wall of the cavernous sinus (MWCS) have been extensively studied and debated. However, the precise nature of this membrane remains unknown. Understanding the anatomical characteristics of the MWCS is crucial, notably in relation to pituitary adenomas, which often invade the cavernous sinus. Indeed, surgical treatment of those tumors is frequently incomplete because of such invasion. The anatomical and molecular basis of the peculiar and often lateralized tropism of adenomatous cells to the cavernous sinus is not yet understood and it has been suggested repeatedly that the MWCS is physiologically frail. During the past three decades, there have been several conflicting accounts of the existence, composition, and continuity of this medial wall, but methodological differences and varying definitions could have contributed to the current lack of consensus regarding it. The aim of this systematic review was to summarize previously published data concerning the existence, anatomy, composition, and continuity of the MWCS.

Neurosurgery for the rhinologist

PURPOSE OF REVIEW

The purpose of this review is to provide a comprehensive anatomical appraisal of the neurosurgical anatomy exposed through the endonasal and paranasal sinuses routes, focusing on the most common expanded endonasal approaches (EEAs) as well as recent advances in this surgical field.

RECENT FINDINGS

The EEAs are redefining the management of skull base pathology. Neurovascular structures previously considered a limitation, can be now approached through these surgical corridors. Advances in this field include the development of new surgical techniques and routes that allow better visualization and access to pathologies located in the ventral skull base. Understanding the surgical anatomy related to EEAs is essential not only for neurosurgeons but also for rhinologists.

SUMMARY

Knowledge of the surgical anatomy of the most common EEAs that utilize paranasal sinuses as a surgical corridor enables more effective management of complex skull base pathologies. Comprehensive anatomical knowledge of these corridors and the surrounding neurovascular structures is crucial to maximize benefits of EEAs and improve outcomes.