Ophthalmology Flashcards
Cornea
-primary absorptive site
Conjuctiva
-thin mucus membrane over sclera
ciliary body
-makes aqueous humor
Routes of drug admin in eye
-local: drops, gels, ointments
-systemic//; inj, oral meds
Regions for absorption
-cornea (primary)
-sclera: mostly collagen, limited absorption
-conjuctiva (systemic)
Limitations to ocular absorption and delivery
-secretions/tears
-volume capacity
-pH and osmolarity
-metabolism
Nasolacrimal duct
-drug can drain from eye to nasal cavity
Eye drop considerations
-limited volume capacity
-defense mechanisms (tears, blinking, corneal barrier)
-3-5 min residence time
Eye ointment considerations
-drug depot in conjunctival sac result in enhanced/sustained absorption
-blurry vision up to 30 min after admin
-difficult to apply correct dose
Eye formulation
-sterile
-7.5-8.5 pH
-pH shifts induce lacrimation
-isotonic best
-hypertonic = cry
-hypotonic effects cornea
-perservatives may cause irritation
-buffer salt effects on mucus secretion
Eye drop admin
-wash hands
-remove contacts
-tilt head back
-form pocket
-hold dropper close to eye w/o touching it
-squeeze dropper into pocket while looking up
-close eyes 2-3 min
-tip head DOWN
-finger on tear duct and apply pressure
Eye ointment admin
-wash hands
-remove contacts
-hold tube near eyeball w/o touching it
-tilt head back, form poackt
-squeeze into pocket
-blink gently and close eye 1-2 min
-wipe excess of ur eyes and tube
contact consideration
-take em out
-wait 15 min to reinsert
-ointment not recommended w contacts
Admin of 2 drops
-wait 5 min between drops if same
-wait 5-10 if 2 different medications
2 ointment admin
-wait 30 min between ointments
1 ointment 1 drop admin
-drop FIRST
-ointment 5-10 min later
Sigs
-O is eye
-A is ear
-S left
-D right
-U both
3 types of conjunctivitis
-bacterial
-viral
-allergic
Bacterial conjunctivitis
-redness, yellow, white, green discharge
-eye stuck shut
-unilateral usually
Common causes bacterial conjunctivitis
-staph aureus
-strept pneumoniae
-haemophilus influenzar
-moraxella catarrhalis
-pseudomonas aeruginosa (highly contagious)
Bacterial tx nonpharma
-avoid sharing
-remove contact lenses until eye is white and no discharge for 24 hours after abx
Bacterial tx pharma
-limited
-topical abx might help
-ointment preferred over drops in children and risk of poor compliance
Abx for bacterial
-erythromycin
-moxifloxacin
-ofloxacin
-trimethoprim-polymyxin B
-slide 31 not sure what i need to know
First line tx approach for bacterial
-polymyxin B/trimethoprim solution
-poly B/ bacitracin ointment
-erythromycin ointment
Alternatives to bacterial tx approaches
-tobramycin or gentamicin solution or ointment
-aminoglycosides have less ram-positive coverage
Second-line tx bacterial
-Fluroroquinolones (ofla-, cipro-, levo-, moxi- floxacin) (poort strept coverage, expensive, resistance developing)
-azithromycin ($$)
Viral conjunctivitis
-watery eyes
-burning, sandy feeling
-morning crust and watery discharge
-other eye involved in 24-28h usually
-part of viral respiratory tract infection
Causes of viral
-adenovirus
-highly contagious
Viral nonpharma tx
-avoid sharing
-remove contact lenses until eye normal for 24 h
viral pharma tx
-relief only
-warm/cool compress
-topical decongestant but limit duration to avoid rebound congestion
Viral decongestants (OTC)
-naphazoline
-tetrahydrozoline
-no more than 72hours
Allergic conjunctivitis
-redness, watery, ITCHING
-maybe morning crust
-both eyes often
-paired w other allergy sx (congestion, sneezing)
-eye rubbing can worsen sx
-acute
-seasonal
-perennial
Common causes of allergic
-airborne allergens
Acute allergic
-sudden onset caused by allergen
-cat dander
Seasonal allergic
-onset days to weeks in repsonse to pollen
-also w rhinitis
perennial allergic
-mild, chronic related to exposure to allergens
-dust mites, mold
Pathophysiology of allergic conjunctivitis
-mast cells activated by allergens
-release histamine, cyto/chemokines
-histamine release causes redness, itching, swelling
Allergic conjunctivitis nonpharma tx
-do not rub eyes
-cool compress
-avoid reduction of contact w known allergen
allergic pharma tx
-antihistamines
-mast cell stabilizers
-multiple acting agents
Acute allergic tx
-artificial tears removes allergens and lubes eye
-topical anithistamine/decongestant combo (P/n)
-topical antihistamine w mast cell stabilizer features (start prior to exposure)
pheniramine/naphazoline
-topical antihistamine and decongestant combo
-1-2 drops upto QID up to 3 days max! (rebound congestion)
Seasonal/perennial tx
-topical antihistamine w mast cell stabilizer
-ketotifen 0.025% cheaper and better availability
-Olopatadine 0.1% or 0.2% used second line
-start tx 2-4 weeks before onset
Antihistamines
Mast cell stabilizer
multi-acting agents for allergic
Uveitis
-intraocular inflammation
-wagon wheel redness associated w iritis
-dilated pupil
-light sensitivity
Uveitis tx
-topical glucocorticoids
-mydratic/cycloplegic
Low strength eye steroids
-dexamethasone
-Medysone
intermediate strength eye steroids
-slide 47
high eye steroid strength
-prednisone acetate 1%
Uveitis tx considerations
-refer to optometrist
-tx 4-6 weeks
-opthalmic steroid toxicity
-inc in intraocular pressure
Ophthalmic steroid toxicity
-secondary infections
-secondary open-angle glaucoma
Intraocular pressure in uveitis
-increases
-6-15+ mmHg
-normal 12-10
Uveitis risk factors
-primary open-angle glaucoma
-ocular HTN
-elderly children
-connective tissue disease
-type 1 DM w myopia
Macular degeneration
-dry or wet
-leading cause of blindness
-risk factors: smoking and age
Dry macular degeneration
-common over 50 years old
-90% of MD cases
-both eyes affected
-gradual loss of vision
Wet macular degeneration
-advanced MD
-vision loss might be rapid
-loss of central vision due to abnormal growth of new blood vessels
Macular degeneration tx goals
-slow progression
-stop visual impairment or blindness
Beta-carotene
-slide 53
-inc risk of lung cancer in smokers
Macular degeneration Rx tx
-vascular endothelial growth factor (VEGF) inhibitors
-all IntraVITREAL injections
-procedure 15 min
-results last 30 days
-Bevacizumab
-Aflibercept
-Ranibizumab
-Pegaptanib
-Verteporfin
VEGF inhibitors
-for formulation of new blood vessels and vascularization of tissues
-antineoplastic agents to treat some cancer and prevent tumors from creating blood vessels
-slow progression and maybe little gain in vision in older people
VEGF inhibitor side effects
-inc BP (CVD, strokes)
-retinal detachment
-inc IOP
-eye infection
-vitreous floaters
Dry eyes causes
-dec tear production (Sjorgen or non Sjorgen)
-inc evaporative loss
Sjorgen dry eyes
-autoimmune disease
-lymphocytic infiltration of exocrine glands
=xerostomia
Dry eyes risk factors
-age
-female
-contact lens wearers
-low humidity environments
-medications
Dry eyes presentation
-dryness
-white/mild red
-irritation
-sandy/gritty
-blurred vision
-light sensititivity
Dry eyes tx
- tears, warm compress (outside factors, dc meds)
- topical tx w secretagogues (liftegrast and cyclosporine) or in office procedures
- Oral tx? (antioxidants or omega-3 FAs), sclera contact lens, surgery, investigation drugs
Non pharma dry eye tx
-blink more
-schedule breaks from screens or reading
-warm compress
-smoking cessation
-humidifiers
-protective eyewear
-minimize exposure to wind or fans
-sufficient oral fluid intake
Dry eyes tear supplementation
-carboxymethylcellulose
-hydroxypopylcellulose
-polyehylene glycol
-DMPG (lipid)
-mineral oil (lipid)
Tear supplementation counseling
-avoid bezalkonium chloride
-preservative free ($$) less likely to cause adverse effects, packaged individually w 24h self life
-meibomian gland dysfunction (MGD) or evaporative should be treated w lipid-supplementing tears
-hard to tell cause of dry eyes, consider lipid containing if pt fails aqueous
Dry eyes Rx tx
-cyclosporine 0.05% emulsion or 0.09% solution
-one drip each eye BID
-single use vials, 0.05% available as multi-dose vial
Cyclosporine
-partial immunomodulator by suppressing inflammation
-onset effect at 4 weeks, full effect 3-6 months
-wait 15 min between eye drops and artificial tears
-dry eye tx
Cyclosporine side effects
-burning/stinging of eye
-s/sx of infection
Drug-induced dry eyes
-a1 and a2 agonists
-anticholinergic
-anticonvulsants
-antihistamines
-antimalarials
-antineoplastics
-antipsychotics
-anxiolytics
-B agonsists and antagonists
-bisphosphonates
-cannbinoids
-decongestants
-diuretics
-retinoids
-oral contraceptives
-tricyclic antidepressants
-benzalkonium chloride preservative
Drug0induced dry eye tx
-warm compress
-inc fluid intake
-humidifier
-inc tear volume (artificial tears or other lube)
-decrease inflammatoin (restasis or Xiidra)
-dc causative agent
-switch to preservative free eye drops
Other drug induced eye disorders
-cataracts
-intraoperative floppy iris syndrom
-optic neuropathy
-retinopathy
Cataracts caused by
-corticosteroids
-phenothiazine
-alkylating agents
-statins
cataracts
-cloudiness in specific part of lens
-will not reverse once formed
-surgical removal of lens maybe necessary to restore vision
Intraoperative Floppy Iris Syndrome
-IRREVERSIBLE
-a1 antagonists
-seen in cataract surgery
-floppy iris
-progressive constriction of pupul
-prolapse of iris through surgical wounds
-preop screening for previous/current use of causititive agents
Intraoperative floppy iris syndrome causitive agents
-a1 ANTAgonists
Optic neuropathy causitive agents
-amiodarone
-ethambutol
-linezolid
-PDE-5 inhibitors
Optic neuropathy
-bilateral vision loss
-dec visual activity
-dec color vision
-gradual sx, no pain
-dc agent usually reverses sx
Retinopathy causitive agents
-aminoquinolines
-antiestrogen agents
-phenothiazines
-retinoids
-perform reg eye exams if pt on these
Retinopathy
-late stage is virtually nonreversible
Meds w eye related effects
-amiodarone =. corneal deposits
-Digoxin = yellow tint/halos (toxicity)
-Anticholinergics = blurred vision
-PDE-5 inhibitors = color changes (blue tint)
-bisphosphonates = inflammation and redness
-topiramate = angle closure glaucoma
-SSRIs = eye tics
Prevention of drug-induced disorder
-education
-regular examinations
-nonpharma tx
-prophylatic meds
-avoid exceding daily dose or duration of therapy
-assess for risk factors
-monitor drug levels
-stress adherence to follow up and monitoring
-encourage communication of meds, OTCs, natural products
