Kelvin Kam-lung Chong
Dr Kelvin Chong is a surgeon-scientist in orbital and oculoplastic surgery and related cell biology. He graduated at the top of his class in the Bachelor of Medicine and Surgery (CUHK) program. He was awarded the Li Po Chun Charitable Trust Fund Overseas Postgraduate Scholarship where he continued later as an international clinical and research fellow at the University of California at Los Angeles (UCLA) (preceptor: Prof. Robert Goldberg) and LA Biomedical Institute (Preceptor: Prof. Terry Smith and Dr Raymond Douglas). His awards included the City Lion Club Gold Medal, Action for Vision Eye Foundation Young Researcher of the Year, Exemplary Eye Resident Award, Achievement Awards from American Academy of Ophthalmology and Asia Pacific Academy of Ophthalmology. Dr. Chong serves as the Coordinator of Orbital and Oculoplastic Surgery at the teaching hospital of the CUHK, the Prince of Wales Hospital and the CUHK Eye Center. He is the current vice President of Hong Kong Society of Ophthalmic Plastic and Reconstructive Surgery (HKSOPRS), Secretary of the Asia-Pacific Society of Ophthalmic Plastic and Reconstructive Surgery (APSOPRS).
Dr. Bipasha Mukherjee is a fellow in Orbit & Oculoplasty from Aravind Eye Hospitals, India, and ICO fellow from University Hospital of Limoges, France, under Prof. Jean-Paul Adenis. She has undergone clinical observerships with stalwarts like Jack Rootman, Richard Collins, Geoff Rose, Mark Duffy, and Robert Goldberg.
She currently heads the department of Orbit, Oculoplasty, Aesthetic & Reconstructive services in Medical Research Foundation, Chennai. She has numerous presentations in national and international conferences and publications in peer-reviewed journals and text books. Her areas of interest include diseases of the orbit and adnexa including tumors, lacrimal surgery, socket reconstruction, traumatic lid and adnexal injuries, training residents and fellows, and photography.
Orbital injuries are important surgical complications to be considered in any eyelid, lacrimal, orbital, socket, sinus, and even neurosurgical procedures. The increasingly popular periocular injections of fillers or autologous tissues may also cause problems due to periorbital tissue reaction and/or needle-related injuries.
Retrobulbar hemorrhages can occur while injecting (sub-Tenon, peribulbar, or retrobulbar) or operating around the periocular region, e.g., blepharoplasties  and ptosis correction, or when the orbit is inadvertently entered during lacrimal (medial orbit), sinus (medial or inferior) , dental (inferior), or neurosurgical (superior or lateral orbit) operations. Details of managing retrobulbar hemorrhage have been covered elsewhere and will not be repeated here.
Extraocular Muscles and Levator Injuries
During Eyelid Operations
The superior rectus muscle may rarely be injured or even transected during levator resection, while injuries to the superior oblique, inferior rectus, or more commonly inferior oblique muscle were reported during fat removal in upper or lower lid blepharoplasties . Injury or disinsertion of the underlying levator aponeurosis causing postoperative ptosis may occur if orbital fat is aggressively removed during upper lid blepharoplasties .
During Sinus or Orbital Operations
Most often, medial rectus (MR)  and rarely inferior rectus and superior and inferior oblique  injuries have been reported during functional endoscopic sinus surgery (FESS). Extraocular muscles may be injured during fracture repair, orbitotomies, or orbital decompression.
Four types of MR injury have been proposed from one study . Type I involves a large-angle exotropia (25 prism diopters) and marked adduction deficit with relatively intact abduction and little or no entrapment (Figs. 52.1 and 52.2). These cases were typically associated with complete transection of the midportion of the MR muscle (Fig. 52.3). Early exploration with suturing of the muscle remnants , along with botulinum toxin injection to the ipsilateral (antagonist) lateral rectus (LR), may improve primary ocular alignment. Severe restriction in the range of horizontal ductions usually persisted. Type II cases revealed a moderate- to large-angle exotropia with combined adduction and abduction deficits suggesting partial MR transection or severe contusion with moderate MR and orbital soft-tissue entrapment. Treatment entailed early repair of the medial wall defect and release of the entrapped MR. Type III cases generally demonstrated no or only mild ocular deviation (typically small esotropia) in primary gaze but a marked abduction deficit, suggestive of a grossly intact or modestly contused muscle with marked bony entrapment. Management is by orbital exploration, release of entrapped orbital tissue, and/or repair of the orbital wall defect. Type IV cases were characterized by only mild degrees of ocular misalignment caused by muscle contusion without entrapment. Conservative management is recommended (Fig. 52.4).
Nine positions of gaze showing restricted adduction in type I injury to MR during FESS
T2-weighted axial MRI image of transected right medial rectus (RMR) in the same patient (Figure reprinted with permission from © Association of Otolaryngologists of India 2015)
Operative view of the transected RMR during exploration
Small left medial wall fracture with no entrapment after FESS
In cases where there is concomitant medial and inferior rectus injury, transposition procedures may not be possible. Inactivation of the antagonist and use of an apically based orbital periosteal flap as a globe tether to center it may be an alternative . Tse et al. reported the use of a suture/titanium T-plate anchoring platform system for one case of medial rectus injury with good improvement .
Lacrimal Gland and Nasolacrimal Injuries
The lacrimal gland may be mistaken as orbital fat during upper lid blepharoplasties which, if inadvertently removed or resected, may lead to significant bleeding due to its vascularity. Dry eye, lateral eyelid drooping due to levator disinsertion, and numbness around the lateral upper lid are other possibilities . Lacrimal sac or nasolacrimal duct injury may occur during medial/inferomedial orbital procedure (fracture repair, orbitotomy, decompression) when the incision on the periorbita (posterior lacrimal crest) is placed too anteriorly.