Ophthalmology: (Acute) vision loss and Ophthalmic Emergencies Flashcards
Conjunctivitis is a disease of the ___ segment
anterior
Treatment for allergic conjunctivitis (red eye)
itchy eyes with or without clear discharge, may be red, burning and puffy, may have conjunctival edema.
Treatment: antihistamine drops, cool compress
not contagious
Outline how alkaline substances can cause chemical burns in the eye
alkaline/bleach lye –> dissolves cornea. More worse than acid; raises the pH of the tissue, causing sapnification of fatty acitds in the cell membranes –> disruption
outline how acidic substances cause injury to the eye
acid –> proteins denature and precipitate –> coagulates cornea
Management, goals of treatment and complications of chemical injury/buns
management: immediate irrigation with 2L of saline. Alcaine drops for pain reduction. 5L+ with retracted lids.
- +/- steroids
goals: reduce infalmmation, manage IOP/(glaucoma drops/pills), control pain, prevent injection and adjesions, promote re-epithelialization of cornea
complications (CABINS): cataracts, adhesions of lid to globe, blindness, infection (secondary), neovascularization, scarring+ GLAUCOMA.
is acute angle closure glaucoma painful?
Yes. It is a painful, non-traumatic vision loss.
Mechanism of action of acute angle closure glaucoma. Symptoms. Management.
Mechanism: contact between the iris and the lens at the pupillary margin increases resistance to the flow of aqueous humour into the anterior chamber. Occlusion of the aqueous humor can further damage the optic nerve, producing pain and ischemia. Visin loss if not fixed within hours.
Epi: F/M.
Symptoms: unilateral ey pain, halos, blurred vision, conjunctival injection, corneal edema, mid-dilated fixed pupil, ELEVATED IOP OVER 30–> EMERGENCY.
Management:
IV fluids, IV gravol, pain control
Lower IOP with topical beta blocker, alpha 2 agonist drops, acetazolamide or IV mannitol.
- control inflammation with prednisolone.
surgery- only for definitive management.
ABC’s and P : medications that lower IOP. What are their MOAs?
A; alpha agonis
beta blocker
c: carbonic anhydrase inhibitor
- all of these decrease aqueous humor production
P: prostaglandin analgoue: increase the OUTFLOW of acqueous humor to reduce the pressure.
Besides acute angle closure, glaucoma is generally painless until late stages. What is the key finding on exam that would indicate glaucoma?
- optic nerve cupping = loss of opti nerve fiber tissue.
- visual field defects: starts peripherally then central acuity is affectd in the late stages.
most common form of glaucoma (not acute vision loss)
primary open angle glaucoma.
- usually asymptomatic until late in disease. ONly treatment is to lower IOP with eyedrops, lasers or surgery.
outline the general flow of acqurous fluid
fluid is created in the ciliary body , and flows into the trabecular meshwork. high pressure results from either too much production at the ciliary body, or poor drainage at the level of the trabecular network.
Endopthalmitis: inflammation/infection of the ____/___ eye. Etiology? Symptoms?
Endopthalmitis: inflammation/infection of the inner eye/intraocular region.
symptoms; PAIN AFTER INTRA-OCULAR SURGERY, decrease in vision, hypopyon: collection of white blood cells in anterior chamber (also seen in corneal ulcers, endopthalmitis or severe iritis). HAVE A HIGH SUSPICION IN ANY PATIENT WITH DECREASED VISION/PAIN AFTER SURGERY
causes: intra-ocular surgery/cataract surgery, anti-VEGF injection, corneal ulcer, trauma, blood-borne infection.
Orbital __ is inflammation of eye tissues behind the orbital __. It is most commonly caused by an acute spread of infection into the __ ___ from either the adjacent sinuses or through the blood.
Orbital cellulitis is inflammation of eye tissues behind the orbital septum. It is most commonly caused by an acute spread of infection into the eye socket from either the adjacent sinuses or through the blood.
Orbital cellulitis is inflammation of eye tissues behind the orbital septum. It is most commonly caused by an acute spread of infection into the eye socket from either the adjacent sinuses or through the blood.
THIS IS LIFE THREATENING: when cellulitis is posterior to the septum, it can lead to ___ ___ ____.
Symptoms, investigations, management of orbital cellulitis?
postieor orbital cellulitis can cause cavernous sinus thrombosis, optic nerve inflammation, meningitis, brain abscess, death.
symptoms: monocular proptosis, lid edema, erythema, decrease and painful extraocular movements, decreased vision, associated sinus disease.
Investigations: CT orbit.
management: IV ANTIBIOTICS/ceftriazone. +/- ENT consult.
complications: cavernous sinus thrombosis.
how does antibiotic treatment differ between preseptal and post orbital septal cellultis?
preseptal: oral if preseptal
IV if post-septal. recall that infections post septally are life threatening, and can lead to cavernous sinus thrombosis.
for all eyelid issues, you must rule out a ___ ___
global rupture
Anterior uveitis: inflammation of the ___ and ___ segment of the eye.
General presentation?
Epidemiology?
Symptoms?
investigations
management
infallmation of the iris and anterior segment of the eye
presentation: photophobia, painful eye, miotic pupil (CONSTRICTED PUPIL), ciliary flush ( ring of red or violet spreading out from around the cornea of the eye.)
investigations: you can see cells in the antieorr chambebr
management: steroids, cover while sleeping, possible cycloplegic (to paralyze iris and reduce pain) dilates pupils. DOES NOT RESPOND TO ANTIBIOTICS
EPI: YOUNGER PATIENT, PT with autoimmune disease (ANK SPONDYLITIS)
what spinal disease is assocaited with anterior uveitis
ankylosing spondylitis
demographic of patient that often gets optic neuritis
younger patietn
optic neuritis is inflammation of the __ ___. Symptoms. Which gender is affected more by it? Disease assocaited with it?
Treatment?
optic neuritis is inflammation of the optic nerve. F>M.
- associated with MS first presentation
symptoms: RAPD (Relative Afferent Pupillary Defect (RAPD) is a condition in which pupils respond differently to light stimuli shone in one eye at a time due to unilateral or asymmetrical disease of the retina or optic nerve (only optic nerve disease occurs in front of the lateral geniculate body). Pain with extraocular movement, loss of vision, colour desaturation, optic disc edema. USUALLY IS UNILATERAL
Treatment: consider high dose oral/IV steroids if vision loss is severe. Speeds recovery, but no evidence of affecting prognosis. MRI to rule out white matter lesions can signify MS.
Corneal ulcers can be __ , __, __ or ___.
bacterial, viral, fungal, or parasitic, ultimately causing inflammatino.
Note: posteiror vitreous detachement is separation from posteiror vitreous humour chamber from the attachemnts to the retina. it can cause a vitreous hemorrhage.
often you’d see flashes and floaters. Probably no changes in visual acuity and field is intact UNLESS there is also a vitreous hemorrhage or UNLESS its also a retinal detachement (in which you’d see a blakc curtain)
This person just sustained a hard hit to the face. they come in like this:
- what do you think they have?
Orbital BlowOut Fracture
Etiology: blunt orbital trauma, leaves the inferior rectus trapped within the fracture of the maxillary bone– it cannot contract to bring the eye back down. the eye then goes up.
Symptoms: enophthalmos (posterior displacement of the eyeball), diplopia, restricted eye movement, up-gaze (see photo), infraorbital nerve anesthesia
Investigations: CT orbits
Management: operative repair + plastics
Retrobulbar Hematoma is a hemorrhae in eye __ ___, causing an orbital ___ ___.
What is the mechanism?
Symptoms?
Management
Retrobulbar hemorrhae is a hemorrhage in the eye socket, causing an orbital compartment syndrome
mechanism: Increased IOP –> Ischemia –> optic nerve damage
symptoms: ocular pain, RAPD proptosis, ophthalmoplegia, diminished vision, increased IOP
management: immediate lateral canthotomy + cantholysis when IOP >40 mmHg or if there is vision loss.
Subconjunctival hemorrage; is it benign? What is it caused by?
etiology: hypertension, eye rubbing, coughing, idiopathic
symptoms: looks bad but is innocuous. no pain or vision loss
PTERYGIUM
PINGUECULA extending onto cornea.
