chalazions, 1401 –1402 chemical injury, 683 See also Ocular chemical injury conjunctivitis, 1396 –1400 See also Conjunctivitis hordeolums, 1401 –1402 nasolacrimal duct (NLD) obstruction, 1402 periorbital cellulitis, 1395 , 1395 f See also Periorbital/orbital cellulitis HOTV visual acuity chart, 1393 , 1393 f left nasolacrimal duct obstruction, 1402 f multiple chalazions, 1401 f neonatal gonorrheal conjunctivitis, 1397 f ocular lavage, irrigation setup, 1401 f orbital cellulitis, CT scan of, 1396 f periorbital cellulitis, 1395 , 1395 f stye, acute, 1401 f vision obstruction, in eye, 1394 f Ophthalmology, consultation, 1401 Ophthalmoplegic migraine, 191 Opioid abuse, 1078 Opportunistic fungal infections, 444 Oppositional defiant disorder, 97 Opsoclonus-myoclonus syndrome, 108 Optic nerve gliomas, 190 Optic neuritis, 193 , 898 Oral antihistamines, 586 t Oral cavity and pharynx trauma, 1117 –1118 caustic injuries, 1118 clinical recognition, 1117 evidences, 1117 initial assessment, 1117 lateral neck radiograph, 1118 f management, 1117 –1118 treatment goals, 1117 triage, 1117 Oral lesions, 348 f associated with systemic disease, 351 –352 causes