Oculoplastics and Orbital Disease
Core concepts
Understand eyelid anatomy and the lacrimal system. Know common eyelid lesions: chalazion (sterile granuloma, treated with warm compresses or excision), hordeolum (infection), basal cell carcinoma (pearly, ulcerated, most common), squamous cell carcinoma, and sebaceous carcinoma (yellow, pagetoid spread). Know orbital disease: thyroid eye disease (restrictive myopathy, proptosis, lid retraction), orbital cellulitis (fever, proptosis, pain with movement, needs antibiotics and imaging), and orbital fractures (blowout with entrapment). Master ptosis evaluation: levator function, Horner syndrome, and myasthenia gravis. Know dacryocystitis (infection of lacrimal sac, tender medial canthus).
Traps
Questions test that orbital cellulitis is distinguished from preseptal cellulitis by proptosis and pain with eye movement. Another trap: distinguishing a chalazion from a hordeolum (chalazion is sterile and chronic; hordeolum is acute infection). Also know that sebaceous carcinoma can masquerade as chronic blepharitis.
Worked example / rule of thumb
A child has fever, proptosis, and pain with eye movement after sinusitis. That is orbital cellulitis, requiring imaging and intravenous antibiotics. Rule of thumb: proptosis plus pain with movement equals orbital, not preseptal, cellulitis.