Shafer’s sign
Suspended pigment particles floating in the anterior vitreous
described as “tobacco dust,”
pathognomonic for a retinal tear
combination of flashing lights and floaters should be considered…
…a retinal detachment until proven otherwise
Finding cotton wool spots in a healthy patient without DM or hypertension…
…consider HIV testing
What antibiotic would you use for a small corneal ulcer in a contact lens wearer?
While most small ulcers can be treated with erythromycin, you must worry about pseudomonas in contact lens wearers. Treat all CL wearers with ciprofloxacin or moxifloxacin. If the ulcer is large, jump right to fortified antibiotics like vancomycin and tobramycin
The major types of penetrating
eye injury are:
eye lid lacerations
corneal lacerations
scleral lacerations
perforating trauma (+/- an exit wound) including occult foreign body penetration (e.g. when metal strikes metal)
There may also be associated injuries to:
intraocular structures — e.g. lens, iris, retina
extraocular structures — e.g. lids, extra-ocular muscles, orbital bones, optic nerve and brain
Marcus-Gunn pupil
Relative afferent pupillary defect
Optic neuritis - papillitis causes
What are the Pulfrich phenomenon and Uhthoff sign?
Both of these are occassionally present in optic neuritis:
Pulfrich phenomenon — altered perception of moving objects
Uhthoff sign — worsening of symptoms with exercise or increase in body temperature
Possible underlying causes of papilloedema
Causes of optic atrophy
Optic atrophy may be the end stage of:
chronic papiloedema chronic optic neuritis glaucoma optic neuropathies (e.g. toxic, metabolic, ischemic and compressive) familial, e.g. retinitis pigmentosa
Compare expected examination findings: optic neuritis and papilloedema
Papillitis (optic neuritis):
pupilary reaction — RAPD present visual acuity — reduced colour vision — red desaturation visual fields — large central scotoma pain on eye movement — present localisation — usually unilateral fundoscopy — blurred disc margins
Papilloedema:
pupilary reaction — normal
visual acuity — normal (transient loss)
colour vision — normal
visual fields — large blind spot, peripheral constriction
pain on eye movement — present
localisation — usually bilateral
fundoscopy — blurred disc margins, no venous pulsation
Oculomotor (III) nerve palsy
The eyes are “down and out” with a droopy eyelid.
The majority of the extraocular muscles are innervated by CN3, so when knocked-out the eye deviates down and out because of the still functioning abducens and superior oblique muscles. In addition, the levator palpebrae (the main lid retractor) is innervated by CN3 and its paralysis gives you a severe eyelid ptosis. Finally, the parasympathetic pupil-constrictor fibers from the Edinger-Westphal nucleus travel within CN3, and their loss gives you a “blown pupil.”
Compressive lesions usually affect the parasympathetic nerve component: a blown pupil is a potential emergency. Whenever you have pupillary involvement, you need an MRI and angiography to rule out a dangerous aneurysm or tumor.
Trochlearis (IV) nerve palsy
Abducens paresis (VI)
Crossed eye. Consider increased intracranial pressure.
(Something about this abrupt turn makes the 6th nerve especially susceptible to high intracranial pressure. Patients with high ICP from pseudotumor cerebri commonly have their 6th nerve(s) knocked out – abducens palsy is actually incorporated into the Dandy criteria for diagnosing PTC.)
if the patient has MG, check …
them up for a thymoma and check their thyroid levels
if a patient complains of a painful Horners …
… think of a carotid dissection and move quickly to rule out this diagnosis.
Szem mekkora
Kb. 24 mm átmérőjű, felülről lefelé kb 0.5 mm-el összelapított
Sclera milyen vastag
N. opticus belépése körül 1-2 mm, előrefele folyamatosan vékonyodik, legvékonyabb az equator előtt közvetlenül a szemizmok tapadása mögött ( 0,3 mm), előre újra vastagabb, különösen a szemizmok tapadásának megfelelően (0,6 mm)
Sclerát mik fúrják át
Cornea rétegei elölről hátrafele
Cornea mérete, vastagsága
13 mm átmérő, kívülről nézve haránt irányban 12 mm, függőlegesen 11 mm
Középen 0,8-0,9 ?! mm, szélein 1,1 mm
M. ciliaris részei kívülről befele
Iris rétegei elölről hátra
Choroidea rétegei kívülről befele