Orbital clock concept: A novel anatomical zoning system for endoscopic vs. external orbital approaches.

PURPOSE: To present a road map and an algorithm that illustrate the rhinologist’s perspective in orbital surgery, guiding surgeons in selecting the most appropriate approach to orbital pathology.

METHODS

We conducted a prospective case series of one hundred consecutive patients undergoing orbital or transorbital endoscopic procedures from January 2023 to January 2025 at the Departments of Otorhinolaryngology and Ophthalmology, Tanta and Alexandria University Hospitals.

RESULTS

Using the right orbit as a clock, the endoscopic endonasal approaches provide access to the medial orbital compartment and orbital apex from 1 to 7 o'clock; the precaruncular approach allows access to the anterior medial compartment from 1 to 6 o'clock. The lower eyelid preseptal approach gives access to the inferior orbital compartment from 4 to 8 o'clock. The lateral retrocanthal or microorbitotomy approach offers access to the lateral orbital compartment from 7 to 11 o'clock. The Superior eyelid crease approach provides access to the superior compartment from 9 to 3 o'clock.

CONCLUSION

The rhinologist’s perspective in orbital surgery has expanded from solely performing medial orbital and optic nerve decompression to bypass the periorbita to medial intraconal lesions and 360-degree access to the orbit by adding transorbital approaches.