Specialised Pathology Of The Eye Flashcards
2)age rel. macular dystrophy (amd)
Progressive degen.of macular in elderly. Most common cause of blindness>60y.m>w, rare in blacks.
Genetic predisposition (abcr gene, ch1)
RF: smoking,exposure to sunlight
MA: retinal Epith.=post mitotic(limited regen.). Degeneration of photoreceptors outer segment(lipid rich, lipofuscin accumulation with age).
Histo: basal lamina&linear deposits=dry
Later, wet amd= choroidal diffusion disturb(atheroscl./ischemia). VGF causes neovasc.(no barrier therefore edema)
Sx:gradual VA loss, colour vision loss.
Wet:serous fluid,lipid,blood,end stage fibrovasc.scar.(irrev.vision loss).
Dry:drusen (yellow deposits),RPE prolif.
Tx: no pharm Tx
Laser: late,wet stage: neovasc. Seen on fluorescin angiography, txd by thermal laser if outside macula. Recurrence!
Photodynamic Tx: late, wet. No dmg to retina. Photothrombosis of neovasc.membr.
vGFi: peg attain, ranibizumab( intravitreal injection).
Px:chr->progressive VA loss.
3) diabetic retinopathy
Epidemiology: main cause of acquired blindness 30-60y.90%of pts with DM dvlp.
Pathology: BM thickening of vessels,loss of pericytes and endothel.(result of glycation end products). Later: capillary closure,ischemia,VGF and ILGF1 causes neovasc in preretinal area and iris. Breakdown of blood retinal barrier. Incr.permeability,edema and fractional detachment. If on iris 2*glaucoma(caused by rubeosis).
Stages:non prolif:microaneurism+retinal haemorrhage.
Prolif: vitreous haemorrhage.
Sx:asymptomatic for LT. Late stage: macular involvement/vitreous haemorrhage.
Dx: opthalmoscopy &stereoscopy funds exam w/ dilated pupils. Fluorescin angio determine if laser is needed.
Rubeosis iridis: by slit lamp&gonioscopy.
Optical coherence tomography: Mac edema, hard exudate->DMmaculopathy.
Tx: Mac edema w/ laser (post.pole). Prolif.retinopathy w/photocoag.
AntiVGF only Tx for maculopathy.
4) HTNsive retinopathy
Arterial changes in HTN (caused by vasopspasm in arteriosclerosis, thickened wall. Arterial HTN is mostfreq cause of retinal vein occlusion.
Pathology: incr.BP, breakdown of BRB/obliteration of arteries,internal bleeding,cotton wool spots,retina/optic disc edema.
Sx:headache,eye pain,vision&VA loss(stages 3&4)
Dx: opthalmosocopy+dip.pupil (changes in retinal vasc common, choroid infarct rare)
Staging:
HTNsive(Keith wagner barker)
I)constr.,tortuous arterioles.
II)severe constr., venous blood flow constr.
III)retinal haemorrhage,hard exudate,cotton wool&retinal edema.
IV)papilledema
Atherosclerotic(schere) I)widening arterioles reflexes II)arteriovenous crossing III)copper wired arteries IV)silver wired arteries
DD: diabetic retinopathy(by opthscopy)
Tx: decr.BPmicroaneurism->vitr.hemorrhage. In presence of papilledema->optic n. Atrophy(VA loss)
5) retinopathy in blood disorders(3)
1) leukemia: malig.hpoetic stem cells. Abnormal prolif.WBC.
Acute: repl.of BM w/ immature cells. Chr:mature(exclusive adults).
1.acute lymphocytic:children(90%respond to Tx,70%cured).
2.acutemyeloblastic:older&adults (30%).
3.chr.malignant:bad prognosis.
Ocular fx: common in acute. Fundus changes(ret.hemorrhage). Acute:cotton wool spots. Chr.myeloblastic:periph.retinal neovasc. Chr:choroidal deposits(“leopard spots”).
Optic n.infiltration:swelling,vision loss. Orbital involvement in children,iris thickening,iritis,subconj.hemorrhage,hyphaemia.
2)anaemia: decr.RBC/Hb in each cell, or both.
Systemic: pallor, atrophic glossitis,koilonychia,ang.stomatitis.
Retinopathy: venous tortuousity,dot&flame shaped hemorrhage,cotton wool spots,Roth spots.
Optic neuropathy: Central scotoma in pernicious. If not Tx with b12, optic atrophy.
3)hyperviscosity: policythemia/abn.plasma prot.
1-polycythemia:neopl.prolif RBC,incr.BM activity,HTN,angina,gout.
2-waldenstrom macroglobulinemia:malig.proliferation->monoclonal IgM.
3-fundus features: retinal hemorrhage,v.dil, retinal v.occl+Conjuctival telangectasia.
6) eye disease&vernal disease
Vernal keratoconjunctivitis: spring catarrh.recc,bilateral.,self limiting infl.of conjunctiva w/periodic incidence.
Sx: burning,itching(especially in warm humid), photophobia,lacrimation.
Palpebral form:upper tarsal conj., pressure of hard,flattopped papillae in cobblestone fashion.congestion.
Bulbar form: red triangular bullae conjunctiva in palpebral area, gelatinous thick accum.of tissue around limbus&awhile dots around limbus.
Can be mix of both.
Causes:immediate HSR(ty1). Fam Hx of atopy (hay fever,asthma,ecz)
Predisp.4-20y, m>w, summer,tropics.
Pathology: conj.epith hyperplastic,vessel prolif.,incr.permeability&vasodil.
Corneal involvement:1or2to limbal lesions.
Vernal keratopathy: puncture Epith.keratitis(lac.system dysfunction by FB,contact lens,smoke), ulcerative vernal keratitis, sub.epith.scarring.
Tx:CST
7)MS
Idiopathic,remitting,demyelination disease involving white matter of CNS. Remits at random freq.(unpredictable).
Sx:
Spinal cord: weakness,stiffness,sensory loss.
Brainstem: diploplia,nystagmus,dysarthria,dysphagia.
Cerebrum: hemiparesis,hemianopsia,dysphasia
Dx: lumbar puncture(leukocytosis,IgG>15% total protein)
MRI: ovoid corpus callosum&periventric. Plaques.
Opth fx:
Optic neuritis(retro bulbar), internuclear opthalmoplegia&nystagmus.
Uncommon: oculi motor n.palsy,hemianopsia.
Rare:uveitis,peri phlebitis.
Tx:CST
8) uveitis in Chr systemic disease(2)
1) sarcoidosis: idiopathic,granulomatous,freq.ocular manifestation. Uveitis within 1yr onset.
-Ant uveitis: acute onset sarcoidosis, chronic granulomatous (older pts). Fat keratitic precipitate, iris nodules->cataract, glaucoma.
Tx: CST! Acute(topic),Chr.(systemic).
-post uveitis:
1-retinal periphlebitis:severe, peri venous exudate, retinal v.occl.
2-choroidal granulomatous: uncomm,vary(multiple small,pale yellow, large ameboid margin,large solitary).
3-retinal granulomatous:rare,white yellow lesions.
4-periph.granulomatous:uncomm.,inferior lesions
5-optic disc granulomatous:rare,doesn’t affect vision.
2)behecet disease: idiopathic,young m, immune mediated vasculitis, bilateral ocular manifestation,30-40y,ant/post uveitis.
1-acute recurr.ant.uveitis: bilateral mobile hypopyon.
2-retinitis: white superficial infiltrate during acute.
3-retinal vasculitis: phlebitis,periarteritis, occlusion,m.ischemia.
4-vascular leakage: retinal/disc.edema.
5-massive retinal exudate: vasc.obliteration.
6-vitritis:severe.
Tx:CST
Other causes: RA,syphillis,TB,UC,AS.
9) uveitis in parasitic infections (3)
1)toxoplasma retinitis: T.Gondii. Obligate IC Protozoa. Cat host.most freq infectious retinitis in immunocomp. Prenatal reactivation/post natal acquired. Assoc.w/cyst rupture.
Active retinitis: assoc w/ant.uveitis(gran/non).
-healed lesions: atrophy&scarring w/ pigm.borders, bilateral.
-focal retinitis: solitary focus,adj.to old pigm.scar. Severe vitritis(impair Fundus visualisation).
-papilitis:infl.of optic n.head.
-atypical lesions: in immunocomp, bilateral multifocal retinitis. Preexisting scars absent(acq. Infection).
Dx:
indirect.immunofluoresc->dead organism+antihumanAb
Hemoagglut->lysed organism onRBC exposed to serum.
ELISA.
Tx:CST,limit scar size. (Indic: macular involvement,sev.vitritis(incr.risk of fibrosis,tractional detachment).
2)toxocariosis:toxocara canis,dog intestinal roundworm.larvae travel to lungs,liver,skin,brain,eye.when die infl.+granuloma.
Ocular toxocarosis has 3 forms:
1-Chr.endopthalmitis: 2-9y,leukocoria(white pupil),strabismus/unilateral vision loss. Ant.uveitis&vitritis. Dense white retinal exudate. Detachment &cataract.tx: CST/pars plana vitrectomy for detachment.
2-post-pole granuloma:6-14,unilateral vision imp. No uveitis.round yellow white macular granuloma.
3-periph.granuloma: adolescent/adult.macular distortion/retinal detachment. No uveitis. ELISA,U.S.
3) Choroidal penumocystosis: p.carinii. Major cause of mortality in AIDS. Choroiditis. Numeral flat,yellow lesions. Bilateral. Decr.VA.
10) keratoconj.sicca: dry eye syndrome.
KCS: non inflam keratopathy, decr.moistening of conj.&cornea. Most common 40-50y.w>m.(hormonal changes/menopause).
-hypovolemic: decr.productive(assoc.w/sjogrens&RA), atrophy/destr.of lacrimal gl.(inf/Tumor/trauma)
-altered composition: vitA defic.,medications(oral contraceptive,retinoids). Environmental infl(nicotine,AC)
Sx: burning,red eye,excess lacrimation from slight stimuli, FB sensation,intense pain. Sight minimally compromised.
Dx: schirmer test: show decr.H20content.
Tear break up time: show mucin content decr.(normal10s,KCS5s).
Slit lamp: dil vessels,minimum peri corneal inject., no tear film meniscus on lower lid. Severe:red eye,tears film=thick mucus and small filaments. Corneal lesion illustrated by fluorescin dye.
Tx:artificial tear solution(drops/gels). If persistent, punctal plug to retain tears still produced.
Px: good
11)periph.corneal disorders in systemic disease(6)
1)periph.furrow( ulcerative) keratitis: heterogenous disorders, all lead to thinning and melting of periph.cornea. May progress to perforation.
Etio: AI:collagenosis,marginal keratitis,sclerokeratitis. Trophic:lack of tear film. Unknown degen process. Most freq. in RA.
2) Keratomalacia: vitAdefic.xerosis of conjunctiva and night bl. Mostfreq cause of blindness in dvlp countries.
3) dellen:tear film instab. Idiopathic/rigid lenses.
4) Marginal keratitis(cattarhal ulcer): HSR to staph toxin.
5)keratitis in RA:
1- sclerosis get keratitis: thick,opaque cornea.
complications:scarring,neovasc and lipid deposits.
2-periph.corneal thinning: resorption of periph stroma.resemble lens.
3-acute stromal keratitis: periph.infiltration, non necrotising.
Complications:scar,neovasc,epithel.breakdown and stromal melting.
4-acute corneal melting: thinned periph cornea.
Tx:CST,keratoplasty.
6)keratitis in systemic vasculitis: bilateral marginal stromal infiltrate. Breakdown epithelium and central spread. Tx:CST
12) incr. intercranial pressure(3)
Normal:
13) ocular myopathies and related disorders(4)
1)strabismus:q28
2)nystagmus: bilateral rhythmic oscillation. Jerky/pendular. Congen/acq. Early childhood. Occur in albinism, cataract, macular scarring, vitreous opacification, colour blindness.
Congen:early childhood, not cured by fixation. Intensity varies w/gaze direction.alternates btw jerky/pendular.
Latent:congen/acq.early childhood. Only by spontaneously covering 1 eye. R oscillation with R fixation. Jerky.
Fixation:only acq. bS/cerebellum disorders(vascular insult/MS/trauma/Tumor).pendular.
Unclear etio.physio at rapidly moving obj.
Tx:convergence(prisms w/outward facing base). Kerstenbaums operation(parallel shifts in horiz.extraocular m. Weaken strong, strengthen weak)
3)myasthenia gravis: uncommon,AI. Weakness of voluntary m. Wx2>m.
Serum Ab. Can be ocular, bulbar or generalised.
4)ptosis: bilateral,asymmetric.worse at night. Diploplia is freq. vertical intraocular opthalmoplegia. Nystagmus movements. Endrophone test(achEi) causes incr. Ach
- Phacomatoses(neuro oculo cutan disease) (7)
1) Struge-weber syndrome: congen.sporadic phacomatoses.
- port wine stain: congen.malformation of vessels w/in superficial dermis. Vascular spaces with thin septa.
- leptomeningeal Hemangioma: seizures/hemianopsia.
- ocular: ipsilat.glaucoma,espiscleral Hemangioma, iris heterochromia,diffuse choroid Hemangioma.
2)neurofibromatosis ty1: neural tumors, short stature, cafe au lait,fibroma mollusca.1* affects cell growth of neural tissue.AD inherit.
Optic: optic n.glioma(bi/unilateral).
Eyelid: nodular/plexiform. If upper, ptosis.
Iris: leisch nodules(2nd/3rd decade, eventually 95%cases).
Glaucoma:rare, unilateral.
Fundus:choroidal nevi, retinal astrocytomas.
3) NF ty2: less common.bilat acoustic neuroma. AD. Ocular lesions are 1st sign. Cataract in 2/3. Fundus: hamartoma of RPE. Oculo motor defects. Early onset cataract.
4)Tuberous sclerosis: triad(epilepsy,mental retardation,adenoma sebaceoum).
Adenoma sebaceoum: fibroangiomatous red papules.butteryfly distrib. Fibrous plaques on forehead.cafe au lait,subungual hamartoma.
Ocular:retinal astrocytoma,hyperpigm.of iris and retina, papilledema.
5)von hipple syndrome: life thr. AD. Cerebellar hemangioblastomas (also in spinal cord,medulla and pons). Renal carcinoma, pheochromocytoma,visceral cysts, policythemia
Ocular:capill.hemangioma of retina/optic n.head.
- Carotid cavernous fistula
Arteriovenous fistula: communication btw a&v. Incr.venous pr. Drainage altered in rate&direction. Arterial pr&perfusion is reduced. Blood into opth.vein undergoes stasis. Incr.episcleral pr. Decr arterial blood flow to CN in cavernous sinus.
-direct:70-90%. Causes:trauma(fracture at base of skull), spontaneous rupture(aneurism,atheroscl).
Clinical triad: pulsatile proptosis,conj.chemosis,flushing noise in head.
Ant:ptosis,chemosis,pulsatile proptosis,cephalic bruit,incr.IOP, ant.segment ischemia, corneal edema,flare, iris atrophy, cataract, rubeosis.
Opthalmoplegia-60-70%due to oculomotor n.dmg(trauma,aneurism,fistula). CN6 most affected(free in sinus).
CT/MRI: prominence of sup opth.v&extraocular enlargement.
Fundus:disc swelling,v.dilation,intraretinal hemorrhage from venostasis.
Px:poor,90%sever visual loss. Immed:optic n.dmg. Delayed: exposure keratopathy.
-indirect fistula: Dural shunt (arterial blood flow through menu gear branches of int/ext.carotid into cavernous sinus. Slow flow- subtle clinical course.
Sx:redness of 1/both by vasc.engorgement.dilated conj&episcleral vessels.exagerated ocular pulsation.incrIOP,opthalmoplegia.
Tx: interventional radiotx.
1) dysthyroid opthalmopathy
AI disorder w/ orbital involvement. Freq assoc w/ thyroid dysfunction.
Epidem:w>m,60%w w/hyperthyroidism, graves->uni/bilateral exopthalmos.
Histology:lymphocytic infiltrate,fibrosis of ocular m.
Sx:painless,20-40y onset,reddened dry eyes, sensation of pressure(like ker.sicca), lim.motility->diploplia. Exopthalmos due to edema.
Eyelid signs:
Dalrymple:retracted upper lid, visible sclera sup. to limbus,wide fissure.
VonGraefe:retracted upper lid at depression.
Gifford:upper lid difficult to evert(edema).
Stellwag: rare blinking
Thickening of m.(rectus inf.+med.)->fibrosis->lim.motil&diploplia. Impaired elevation (false incr.IOP) DD:tumors/pseudo tumors Tx: acute(Tx of thyroid dysfunction,systemic CST,radiotx of orbital cavity)
Recurring:decompression
Exposure keratitis:artificial tears, tarsorrhaphy (suture of fissure)
Px: VA remains good.
