Objective?To explore the use of the endoscopic endonasal transclival approach (EEA) for clipping anterior inferior cerebellar artery (AICA), posterior inferior cerebellar artery (PICA), and vertebral artery (VA) aneurysms. Design?Anatomical study. Participants?Fifteen adult cadavers. Main Outcome Measures?Length of artery exposed and distance from the nasal ala to the arteries. Results?The length of the right and left VA exposed were 1.7???0.6 cm and 1.6???0.6 cm, respectively. The distance to the right VA was 11.1???0.9 cm and to the left was 11.1???0.8 cm. Right and left AICA were exposed for an average length of 1.1???0.3 cm and 0.8???0.3 cm, respectively. The distance to the right AICA was 10.3???0.8 cm and to the left was 10.3???0.8 cm. The right PICA was exposed for a length of 0.5???0.2 cm at a distance of 10.9???0.5 cm. The left PICA was exposed for a length of 0.5???0.2 cm at a distance of 11.1???0.9 cm. Conclusion?The EEA can provide direct access to AICA, PICA, and VA, making it a potential alternative to the traditional approaches for the clipping of aneurysms arising from those arteries.

The endoscopic endonasal transclival approach represents a potentially feasible surgical corridor to treat aneurysms arising from these vessels.

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Background:The medial and inferior recti encompass the ideal surgical corridor to approach the intraconal space endonasally. Here, we describe 3 different maneuvers to achieve greater access to orbital contents through an expanded endonasal approach (EEA). Methods:Four human cadaver heads were dissected bilaterally (n = 8). EEA to the medial intraconal orbit was executed. The following 3 maneuvers were performed: (1) anterior: extraocular muscles control (EOM); (2) posterior: annulus of Zinn (AZ) release; and (3) anterior/posterior combined. Measurements of the inferior and medial rectus corridor at the level of anterior ethmoidal artery (AEA) and posterior ethmoidal artery (PEA) and extent of optic nerve and medial rectus visualization was performed before and a er each maneuver.Results: Medial rectus length (MRL) and optic nerve length (ONL) achieved were 1.72 ± 0.28 cm and 0.85 ± 0.2 cm, respectively. Mean caudal-rostral distances between the rectus muscles at the level of the AEA and PEA were 3.45 ± 0.7 mm and 1.30 ± 0.3 mm, respectively. A er EOM control, mean caudal-rostral distances at the same level were as follows: AEA 4.90 ± 1.15 mm (p = 0.009) and PEA 1.70 ± 0.20 mm (p = 0.016). With AZ release, MRL was 2.20 ± 0.7 cm (p = 0.002) and ONL was 1.30 ± 0.2 cm (p = 0.003), with mean rostral-caudal distance at the level of AEA at 4.03 ± 0.8 mm (p = 0.16) and PEA at 1.71 ± 0.36 mm (p = 0.039). Mean caudal-rostral distances achieved with AZ release and EOM control were as follows: AEA 5.6 ± 1.2 mm (p = 0.001) and PEA 2.15 ± 0.4 mm (p = 0.001). Conclusion:Progressive access to the orbital contents is afforded with the 3 delineated maneuvers. The magnitude of access is optimized with the combined maneuver. The actual anterior/posterior location of the target will determine which maneuvers are required. C 2018 ARS-AAOA, LLC. Key Words: orbital/ocular; endoscopy; endoscopic minimally invasive surgery of the skull base; FESS; endoscopic skull base surgery How to Cite this Article: Lemos-Rodriguez AM, Farzal Z, Overton LJ, et al. Analysis of anterior and posterior maneuvers to enhance intraconal exposure. Int Forum Allergy Rhinol. 2019;9:556-561. E ndoscopic endonasal approaches have evolved through the years, from the resection of pituitary and transsellar

N/A. Laryngoscope, 127:585-591, 2017.