Retina
Anatomy of the Retina
The Ten Layers of the Retina
1. Pigment epithelium layer2. Layer of rods and cones3. External limiting membrane 4. Outer nuclear layer5. Outer plexiform layer6. Inner nuclear layer7. Inner plexiform layer8. Ganglion cell layer9. Nerve fibre layer10.Internal limiting membrane
Symptoms in retinal diseases Night blindness Peripheral visual disturbance Central visual disturbance Color visual disturbance Metamorphopsia Micropsia Macropsia Photopsia Muscae volitantes (floaters) Without symptoms
Examinations Visual Acuity Dark Adaptation Color vision (Ishihara) Visual field :
confrontation test Goldmann perimetry Bjerrum tangent screen Octopus perimetry
Ophthalmoscopy direct ophthalmoscopy indirect ophthalmoscopy biomicroscopy + contact lens/ Hruby lens/ +90 D lens
DIRECTOPHTHALMOSCOPY
Fundus Reflex
Lens Opacity
External Light
INDIRECTOPHTHAL-MOSCOPY
DIRECT
INDIRECT
BIOM
Specific Examinations
Fundus fluorescein angiography (FFA)Ultrasonography (USG)Electroretinography
FundusFluoresceinAngiography(FFA)
ULTRASONOGRAPHYof the NORMAL EYE
Diseases of the retinaCongenital anomaliesTrauma InflammationRetinal detachmentVascular disordersDegenerationNeoplasma
Retinal diseases to be discussed
Retinal detachment (ablatio retina)Retinal artery occlusionRetinal vein occlusionDiabetic retinopathyHypertensive retinopathyRetinitis pigmentosa
Retinal Detachment= ablatio retina
separatio retinae
A condition where the sensoric retinal
layer seperates from the retinal pigment epithelium layer (RPE)
Retinal Detachment
Classification based on pathogenesis : Rhegmatogenous RD
Break/tear in the retina (degeneration/ trauma) fluid from the vitreus cavity enters sub-retina retina detached
Nonrhegmatogenous RDProcess behind retina (tumor/
inflammation) subretinal fluid retina detached
Tractional RDFibrosis in vitreus (bleeding/inflammation) retinal traction retina detached
Retinal Detachment
Subjective symptoms Photopsia, floaters
due to retinal traction, vitreous bleeding Dark shadow/curtain
starts peripherally Reduced Vision
macular involvement or vitreous bleeding Metamorphopsia
macular involvement (detached)
Retinal Detachment
Objective signs Low IOP Relatively calm anterior segment Funduscopy
Detached retina greyish in color, elevated towards the vitreous cavity, vessels also elevated, surface often multi-lobulated
Retinal Tears
Cryo/ LaserProphylaxis
Retinal Detachment
Retinal DetachmentTherapy
Rhegmatogenous
Tractional Nonrhegmatogenous towards primary d. Surgical objectives
close the tear remove subretinal fluid remove vitreous traction
Surgery(Retinal repositioning)
Retinal Artery OcclusionA condition where the retinal artery is
occluded by an embolusSymptom: sudden visual loss without painTwo types :
Central (CRAO) - occlusion behind the lamina cribrosa
Branch (BRAO) - occlusion in front of lamina cribrosa
Retinal Artery Occlusion
Causes :ArteriosclerosisHypertensionCarotid arterial diseaseDiabetes mellitusValvular heart diseaseOthers: oral contraception, trauma,
coagulopathy, toxoplasmosis, etc.
Retinal Arterial Occlusion
Symptoms and signs:Sudden blurred vision (HM - LP)Calm anterior segmentFunduscopy
‘cherry-red spot’ (greyish pale retina except at the fovea)
small arteries, uneven caliber small veins, segmental
Retinal Arterial Occlusion
Branch RAO If macula not involved, vision relatively stable Retina pale only at the involved area A/v changes only at the occluded branchComplications: Papil atrophy NVI + NVGPrognosis: Poor. Visual recovery only if : 1. Occlusion overcome
within 1-2 hours after onset, 2. Occlusion temporary (spasm), 3. Cilioretinal artery present
BRAO
CRAO
Retinal Arterial Occlusion
Therapy: The aim of treatment is to quickly recover the
arterial circulation by lowering the IOP : paracentesis (AH aspirated 0.15 - 0.2 cc) Acetazolamide (Diamox) 500 mg. i.v. digital massage of eyeball inhalation of 95% O2 - 5% CO2 mixture
Look for cause consult Internal Medicine
Retinal Venous OcclusionSimilar to RAO, painless sudden loss of
vision as presenting symptom Two types:
central (CRVO) occlusion behind lamina cribrosa
branch (BRVO) occlusion in front of lamina cribrosa
RVO 4-5 times more often than RAO
Retinal Venous Occlusion
Causes : hypertension & arteriosclerosis (60%)
Common adventitial sheath at a-v crossing.
Sclerosis --> vein compressed --> slowed flow --> thrombus --> occlusion
open angle glaucoma (40-70%) hyperviscosity (polycythemia, hyperli-pidemia,
leukemia, etc) thromblophlebitis etc.
Retinal Venous Occlusion
Symptoms and signs : sudden loss of vision calm anterior segment funduscopy :
dilated and tortuous vein edema, hemorrhage, soft exudate
Complication : NVG
30-35% of CRVO, 1-3 months after onset
CRVO
BRVO
Retinal Venous Occlusion
Branch RVO : NVG seldom nasal branch --> no visual disturbance
Prognosis : without NVG --> edema, hemorrhage, exudate
slowly absorbed Therapy :
medical therapy of no benefit laser photocoagulation look for cause --> consult Internal Medicine
Diabetic RetinopathyDR is a retinal abnormality in a diabetic
due to microangiopathy Almost always bilateral although the
stages may be different incidence increased with duration of
DM : > 20 years 50% retinopathy > 30 years 80% more
Diabetic Retinopathy
Juvenile onset DM : delayed onset of DR.
Mature onset DM (age > 40 yrs) : onset sooner
Good metabolic control will delay the onset of DR
Main cause of new blindness in the US
Diabetic Retinopathy
Signs : microaneurysm retinal hemorrhage hard exudate soft exudate retinal edema collateral vessels (IRMA-IntraRetinal Microvasular
Abnormalities) venous beading CNPA (Capillary Non Perfusion Area) neovascularization & gliosis
Diabetic Retinopathy
Complications : vitreous hemorrhage tractional retinal detachment
Classification : nonproliferative (“background”) = NPDR proliferative = PDR diabetic macular edema = DME
Diabetic Retinopathy
NPDR early : signs 1 to 8 severe = preproliferative
PDR early : + sign 9 severe : + complications
Mild NPDR
Photo
FFA
Severe NPDR
Venous Beading
PDR
NVD
Severe PDR
Diabetic Retinopathy
Therapy metabolic control laser photocoagulation
indicated in severe NPDR early PDR DME
vitrectomy and retinal repositioning in Vitreous Hemorrhage and Retinal
Detachment complications
PRP PRP
FOCAL
PARS PLANA VITRECTOMY
Hypertensive Retinopathy
Changes in the retina of a hypertensive patient is due to hypertension and arteriosclerosis
changes due to hypertension : arteriole attenuation focal constriction/spasm hemorrhage and exudate papil edema
changes due to arteriosclerosis : changes in arteriole light reflex changes in a-v crossing
Hipertensive Retinopathy
Changes due to hypertension : arteriole attenuation
normal A:V ratio 2:3 or 3:4 attenuation < 3:4 (e.g. 1:2, 1:3)
focal constriction hemorrhage hard exudate soft exudate papil edema
Hipertensive Retinopathy
Changes due to arteriosclerosis changes in arteriole light reflex changes in a-v crossing
SCHEIE classification(1953) 5 stages of hypertension and 5 stages of
arteriosclerosis are used
Attenuation
Focal Spasm
Venous Indentation
HypertensiveRetinopathy
HypertensiveRetinopathy
Papil Edema
CWSHemorrhage
SCHEIE classification
Hypertension Arteriosclerosis
Attenuation FocalSpasm
Hemorrhage Exudate PapilEdema
Light reflex
A-v crossingGrade
0
1
2
3
4
3 : 4
1 : 2
1 : 3
1 : 4
soft thread
1 : 1
1 : 1
2 : 3
1 : 3
distaloccl.
(-)
(-)
(-)
(+)
(+)
(-)
(-)
(-)
(+)
(+)
(-)
(-)
(-)
(-)
(+)
Yellow line
Widened
Copper
Silver
Fibrous thread
N
V.Inden
V.Inden
Dist dilat
Similar to 3
SCHEIE Classification
Hypertension Arteriosclerosis
0 0
Grade 1 Grade 1
Grade 2 Grade 2
Grade 3 Grade 3
Grade 4 Grade 4
Hipertensive Retinopathy
Therapy : toward the hypertension hypertensive signs may disappear;
sclerotic signs persist papil edema, focal constriction quickly
disappear hemorrhage, soft exudate disappear within
several weeks-months hard exudate disappear within 4-6 months or
more
Retinitis PigmentosaA hereditary disease in which a
pigmentary degeneration of the retina occurs
Characteristically there is a progressive degeneration of the photoreceptors and RPE
most severe if X-linked recessive, least severe if autosomal dominant
Retinitis Pigmentosa
Subjective symptoms : Nightblindness Gradual reduction of visual acuity up to
less than 6/60 within 4 - 10 years. In X-linked this occurs usually earlier (reading disturbance at age 20, blindness at age 40)
often accompanied by hearing disturbance
Retinitis Pigmentosa
Funduscopy : attenuation of retinal vessels in the midperiphery bone-specule pigmentation esp.
along vessels; retina slightly dirty grey in color Perimetry :
annular scotoma Therapy :
untreatable low vision aids (LVA) genetic counseling
Retinitis Pigmentosa
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