Oculoplastics, Orbit and Lacrimal System
Oculoplastics, orbit and lacrimal disease covers eyelid position, orbital inflammation and tumours, and the watering eye. The exam favours anatomical reasoning: which layer is lax, which muscle is weak, and which compartment is involved.
Core rules
- Involutional ectropion: horizontal lid laxity, treated by lateral tarsal strip or medial spindle. Entropion: override of the lower lid retractors, treated by Quickert sutures or lateral tarsal strip plus retractor reinsertion.
- Ptosis: measure margin-reflex distance, levator function and lagophthalmos. Levator function above 10 mm favours levator advancement; poor function favours a frontalis sling, especially in congenital ptosis with amblyopia risk.
- Orbital cellulitis: fever, proptosis, pain on movement and reduced motility; admit for intravenous antibiotics and image if there is any doubt. Preseptal cellulitis does not limit eye movement.
- Thyroid eye disease: treatment follows activity and severity; smoking cessation, lubricants, selenium in mild disease, steroid or teprotumumab for active disease, and rehabilitative surgery (orbital decompression, strabismus, lid) when stable.
- Lacrimal: epiphora with a positive dye disappearance test and blocked syringing suggests nasolacrimal duct obstruction; dacryocystorhinostomy is definitive.
- Orbital tumours: think of age and location - rhabdomyosarcoma in children, lymphoma in older adults, cavernous haemangioma in middle age.
Worked example
A 14-month-old has a watery left eye since birth with intermittent discharge and crusting. The dye disappearance test is delayed and regurgitation on pressure over the sac is positive. This is congenital nasolacrimal duct obstruction. You manage conservatively with massage and hygiene until about 12–18 months, because most cases resolve spontaneously; if it persists, probing is the next step, with intubation or dacryocystorhinostomy for recurrent failure.
Traps
Missing orbital cellulitis because the eye is white, operating on a watering eye without syringing, and diagnosing thyroid eye disease without checking for compressive optic neuropathy.