Endoscopic orbital surgery is one of the most rapidly advancing areas in modern day rhinology and ophthalmic plastic surgery. While endoscopic techniques have been adapted for lacrimal and orbital decompression surgery for more than two decades, advanced endoscopic endonasal and periocular approaches to the orbital apex and skull base have only recently been developed. Dr. Bleier and his collaborators at the Center for Thyroid Eye Disease and Orbital Surgery are global leaders in pioneering multiple new minimally invasive approaches to remove orbital tumors entirely through the nose as well as novel techniques in orbital decompression and dacryocystorhinostomy.
ORBIT Staging System
The ORBIT classification system is an anatomic-based framework developed by Dr. Bleier and colleagues and is recognized as the international gold-standard in high-quality outcomes reporting for all primary benign orbital tumors.
Surgical Anatomy and Patient Selection
3-dimensionally rendered orbital tumors of two different patients (a-c and d-f). Line 1 represents the long axis of the Optic Nerve (N) while Line 2 represents the plane of resectability which dictates which tumors are amenable to endoscopic resection. Note how these lines divide the tumor into 3 zones (T1) easily resectable, (T2) resectable, and (T3) unresectable.
Illustration of bimanual technique, which allows multiple instruments to be introduced into both nostrils. For a tumor of the left orbital apex (white arrow), the endoscope (1) and retractor (2) are placed in the right nostril and access the lesion through a posterior septectomy. The assistant controls the endoscope and may introduce a fourth instrument if necessary. The primary dissecting instrument (3) is introduced through the left nostril and controlled with the primary surgeon’s dominant hand.
Healy DY, Jr, Lee NG, Freitag SK, Bleier BS. Endoscopic bimanual approach to an intraconal cavernous hemangioma of the orbital apex with vascularized flap reconstruction. Ophthal Plast Reconstr Surg. 2014 Jul–Aug;30(4):e104–6. PMID: 2483343.
A. Endoscopic view of the left medial intraconal space in the cadaveric dissection. The medial rectus muscle (MRM) is retracted medially to reveal the oculomotor nerve trunk (black arrow) emanating from the orbital apex at the level of the sphenoid sinus (SS) face. Two discreet branches of the inferomedial muscular trunk of the ophthalmic artery (white arrows) are clearly seen crossing the intraconal space dividing it into three conceptual anatomic zones (A, B, and C). B. Illustration of the lateral surface of the MRM demonstrating the general pattern of innervation with a large proximal oculomotor trunk which divides into a variety of smaller distal branches. The red circles represent the approximate location and caliber of all vascular branches identified in the ten cadaveric orbits. Note the clustering of vessels along the midportion and inferior border of the MRM. C and D. Matched endoscopic surgical view of the left orbit demonstrating the appearance of the arterial branches (white arrows) and oculomotor trunk (black arrow) during endoscopic resection of a cavernous hemangioma (CH).
Bleier BS, Healy DY, Jr, Chhabra N, Freitag S. Compartmental endoscopic surgical anatomy of the medial intraconal orbital space. Int Forum Allergy Rhinol. 2014 Jul;4(7):587–91. PMID: 24687956.