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Published on: May 12, 2011
Dangers of orbital retraction in transorbital neuroendoscopic surgery
Ayushi Agarwal1, Jessica Y Tong2, Dinesh Selva1,3,4
1South Australian Institute of Ophthalmology, The Royal Adelaide Hospital, Adelaide, Australia.
Purpose:
This review summarizes the risks associated with orbital retraction in transorbital neuroendoscopic surgery (TONES) and proposes practical strategies to optimize surgical freedom while preserving visual function.
Methods:
A qualitative review synthesized through a systematic literature search of PubMed (MEDLINE) database. Studies involving human or cadaveric TONES and endoscopic transorbital approaches were reviewed.
Results:
Ten studies met inclusion criteria, comprising cadaveric as well as human subjects. Virtual-reality and cadaveric models revealed that 10-11 mm of globe displacement provides adequate surgical freedom, whereas sustained retraction beyond approximately 15 mm results in steep rises in intraocular and intra-orbital pressure posing a higher risk of orbital compartment syndrome. Clinical reports link prolonged retraction to transient or permanent mydriasis, ocular hypotony, decompression retinopathy, and visual loss.
Conclusion:
Orbital retraction is central to TONES but is the principal driver of ocular morbidity. Based on the available evidence, retraction should be dynamic, gentle, and intermittent, with globe displacement generally limited to 10-12 mm. Apex-directed focal pressure should be avoided, and continuous monitoring of pupil and intraocular pressure is essential. Multidisciplinary protocols are recommended to standardize safe retraction practices while preserving the advantages of TONES.
