Ophthal misc Flashcards
Features of afferent defect and cause
No direct response, intact consensual response in other eye
No consensual response from initiation in contralateral eye
Total CN II lesion
Features of RAPD (marcus-gunn pupil) and causes
Minor constriction to direct light
Dilatation on moving light from normal to abnormal eye
optic neuritis
Optic atrophy
Retinal disease
Features of efferent defects and causes
Dilated pupil does not react to light
Consensual response intact in contralateral eye
3rd nerve palsy
Causes of a fixed dilated pupil
Mydiatrics e.g. tropicamide
Iris trauma
Acute glaucoma
CN III compression (surgical)
Features of Horner’s syndrome and causes
Ptosis
Mydriasis
Anhidrosis
Central (MS, Lateral Medullary Syndrome)
Pre-ganglionic (Pancoast tumour, CVA insertion)
Post-ganglionic (cavernous sinus thrombus, CN 3-6 palsy)
Features of a holmes-adie pupil and causes
Dilated pupil
- no response to light
- sluggish accommodation
Damaged post-ganglion fibres
Viral/bacterial infection of ANS
Features of an argyll-Robertson pupil and causes
Small, irregular pupil
Sluggish response to light
Accommodation intact
Damage to the ciliar ganglion:
DM
Syphilis (quaternary)
Features of Hutchinson’s pupil and causes
Unilaterally dilated pupil
Unresponsive to light
- [1] ipsilateral pupil constricts (PNS irritation)
- [2] ipsilateral pupil dilates (PNS inhibited)
- [3] contralateral pupil constricts (PNS irritation)
- [4] contralateral pupil dilates (poor prognosis)
Intracranial mass / raised ICP head trauma
Features fo optic atrophy
Reduced acuity
Reduced colour vision (esp. red)
Central scotoma
Pale optic disc
RAPD
Causes of optic atrophy
Congenital: HMSN/CMT, friedrich’s ataxia, reinitis, pigmentosa, LHON
Alcohol/toxins : EtOH, ethambutol, lead, B12
Compression: neoplasia, glaucoma, paget’s
vascular: DM, GCA, stroke
Inflammatory: MS
Sarcoidosis
Infection: VZV, TB< syhpilis
Neoplastic infiltration: leukaemia, lymphoma
Features of corneal abrasion clinically and on investigation
Epithelial breech without keratitis
S/S: pain, photophobia, blurred vision, visible defect
Ix: slit lamp fluorescein staining defect green
Management for corneal abrasion
infection prophylaxis (chloramphenicol ointment)
Features of ophthalmic shingles/herpes zoster ophthalmicus
CN V1 reactivation of VZV (10% of all shingles)
S/S: pain → blistering rash; 40% associated keratitis/uveitis
Hutchinson’s sign = nose-tip zoster (naso-ciliary branch) → ophthalmic involvement = keratitis ± corneal ulceration ± iritis
Management for Ophthalmic shingles / Herpes Zoster Opthalmicus
Fundoscopy, slit lamp fluorescein staining
referral → oral aciclovir (7-10 days) ± topical corticosteroids (if inflammation)
Complications of Ophthalmic shingles / Herpes Zoster Opthalmicus
Ptosis
Post-herpetic neuralgia
Ocular (conjunctivitis, keratitis, episcleritis, anterior uveitis)
What conditions need urgent ophthalmology assessment
Acute glaucoma
Corneal ulcer, foreign body
Contact-lens-related red eye
Anterior uveitis
Scleritis
Trauma, chemical injuries
Neonatal conjunctivitis
Signs and symptoms of vitreous haemorrhage
Small bleeds → small black dots in vision and ring floaters
Large bleeds → loss of red reflex, retina not visualised
Causes of vitreous haemorrhage
Angiogenesis (DM accounts for 50%)
Retinal tear, detachment or trauma
RF: warfarin
Investigations and management of vitreous haemorrhage
B-scan (brightness scan) ultrasonography
Small → supportive - will spontaneously reabsorb
Larger → vitrectomy
Features of Tobacco-alcohol ambylopia and management
toxic effects of cyanide radicals combined with thiamine deficiency
S/S: optic atrophy, loss of red/green discrimination, scotomata
Mx: vitamins may help
What is lagophthalmos, what causes it and how is it managed
difficulty closing the lid over the globe → exposure keratitis
Exophthalmos, facial palsy
Mx: lubrication (liquid paraffin), tarsorrhaphy (eyelids partially sewn together; if corneal ulcers)
Features of pinguecula
yellow vascular nodules either side of the cornea
Features of pterygium
yellow vascular nodules growing over the cornea → decreased vision):
Benign growth of the conjunctiva
Associations with dusty, wind-blown lifestyles and sun exposure (i.e. desert dwellers)
Causes of exophthalmos
Graves’ disease
Orbital cellulitis
Trauma
Idiopathic
Vasculitis
Neoplasms, optic glioma
Carotid-cavernous fistula
Management for foreign bodies in the eye
XR eye, fluorescein
Refer to eye emergency - do not remove
Mx: chloramphenicol drops, eyepatch, mydriatics/cycloplegics (decrease pain)
Management for intra-ocular haemorrhage
small amounts clear spontaneously; large may need evacuation
May cause acute glaucoma → emergency
Symptoms and signs of orbital blowout fractures
herniation into maxillary /ethmoid sinus
Ophthalmoplegia + diplopia
Loss of sensation to the lower lid (infra-orbital nerve injury)
Ipsilateral epistaxis (ant. ethmoid artery rupture)
Decreased acuity
Irregular pupil reacting slowly to light
Management for orbital blowout fracture
maxilla-facial/ophthalmology referral → fracture reduction / muscle release
Management for chemical injury
Worse if alkaline
Irrigate and refer urgently
Features of trachoma
Chlamydia trachomatis; spread by flies
inflammatory reaction → scarring → lid distortion → entropion → eyelashes scratch cornea → ulceration → blindness
Management for trachoma
Tetracyclines
Features of onchocerciasis
aka river blindness
Microfilariae of nematode Onchocerca volvulus
spread by flies
fly bites → microfilariae infection → invade the eye → inflammation → fibrosis → corneal opacities and synechiae
Management for onchocerciasis
Ivermectin
Features of xerophthalmia
Vitamin A deficiency
night blindness, dry conjunctiva, corneal ulceration/perforation
Manage with vitamin A supplementation
