Anatomic analysis specific for the endoscopic approach to the inferior, medial and lateral orbit

Introduction: The endoscopic approaches to the medial and inferior orbital walls have continued to grow in popularity. The ability to provide a safe approach to the orbit through this technique has been described in a handful of studies. Even though metric analyses have been conducted on orbital anatomy, few have outlined the anatomical relations pertinent to endoscopic surgery. The goal is to provide improved understanding of the complex anatomy encountered through anatomical dissections and metric analysis of the orbit. This information could assist in approach selection during preoperative planning. Methods: Anatomical dissections via transantral and endonasal approaches were used to define the limits with current endoscopic sinus surgery instrumentation. The surface area was then calculated of the floor and medial wall to assess access created by the approaches. The path of the infraorbital canal was conducted to assess its placement within the orbital floor. Results: The transantral and endonasal approaches to the orbit provided an adequate surgical window inferiorly and medially. This was confirmed by the surface area calculations. Access laterally was also possible, however, it became limited as dissection advanced superior to the lateral rectus muscle. The infraorbital canal was located consistently at midline on the orbital floor. Conclusion: Endoscopic access to the medial and inferior parts of the orbit is feasible and creates adequate access with current instrumentation. Knowing the surgical boundaries and the amount of exposure created can assist the surgeon in deciding a minimally invasive approach

Endoscopic repair of an injured internal carotid artery utilizing femoral endovascular closure devices

Objectives/Hypothesis: Injury to the internal carotid artery is a feared complication of endoscopic endonasal surgery of the skull base. Such an event, although rare, is associated with high morbidity and mortality. Even if bleeding is controlled, permanent neurological defects frequently persist. Many techniques have been developed to manage internal carotid artery rupture with varying degrees of success. The purpose of this study was to explore endoscopic management of arterial damage with endovascular closure devices used for a femoral arteriotomy. The ability to remotely suture a damaged artery permits the possible adaptation of this technology in managing endoscopic arterial complications

Access to the Parapharyngeal Space: An Anatomical Study Comparing the Endoscopic and Open Approaches

Objectives/HypothesisA subtemporal preauricular approach to the infratemporal fossa and parapharyngeal space has been the traditional path to tumors of this region. The morbidity associated with this procedure has lead to the pursuit of less invasive techniques. Endoscopic access using a minimally invasive transmaxillary/transpterygoid approach potentially may obviate the drawbacks associated with open surgery. The anatomy of the parapharyngeal space is complex and critical; therefore, a comparison of the anatomy exposed by these different approaches could aid in the decision making toward a minimally invasive surgical corridor

Anatomical and computed tomographic analysis of the transcochlear and endoscopic transclival approaches to the petroclival region.

Objectives/Hypothesis Advances in the field of skull base surgery aim to maximize anatomical exposure while minimizing patient morbidity. The petroclival region of the skull base presents numerous challenges for surgical access due to the complex anatomy. The transcochlear approach to the region provides adequate access; however, the resection involved sacrifices hearing and results in at least a grade 3 facial palsy. An endoscopic endonasal approach could potentially avoid negative patient outcomes while providing a desirable surgical window in a select patient population

Transmaxillary approach to the infratemporal fossa

The infratemporal fossa posses significant challenges to surgical access. Complete extirpation of the pathology in the region most be balanced with iatrogenic deficits and tumor biology. The advent of endoscopy has expanded the reach of anterior transnasal transmaxillary approaches. Herein we present a brief description of these techniques

What is the best route to the Meckel cave? Anatomical comparison between the endoscopic endonasal approach and a lateral approach

BackgroundTraditionally, a pterional approach is utilized to access the Meckel cave. Depending on the tumor location, extradural dissection of the Gasserian ganglion can be performed. An endoscopic endonasal access could potentially avoid a craniotomy in these cases

Meckel's cave access: anatomic study comparing the endoscopic transantral and endonasal approaches

Recent advances in endonasal endoscopy have facilitated the surgical access to the lateral skull base including areas such as Meckel's cave. This approach has been well documented, however, few studies have outlined transantral specific access to Meckel's. A transantral approach provides a direct pathway to this region obviating the need for extensive endonasal and transsphenoidal resection. Our aim in this study is to compare the anatomical perspectives obtained in endonasal and transantral approaches. We prepared 14 cadaveric specimens with intravascular injections of colored latex. Eight cadavers underwent endoscopic endonasal transpterygoid approaches to Meckel's cave. Six additional specimens underwent an endoscopic transantral approach to the same region. Photographic evidence was obtained for review. 30 CT scans were analyzed to measure comparative distances to Meckel's cave for both approaches. The endoscopic approaches provided a direct access to the anterior and inferior portions of Meckel's cave. However, the transantral approach required shorter instrumentation, and did not require clearing of the endonasal corridor. This approach gave an anterior view of Meckel's cave making posterior dissection more difficult. A transantral approach to Meckel's cave provides access similar to the endonasal approach with minimal invasiveness. Some of the morbidity associated with extensive endonasal resection could possibly be avoided. Better understanding of the complex skull base anatomy, from different perspectives, helps to improve current endoscopic skull base surgery and to develop new alternatives, consequently, leading to improvements in safety and efficacy