DISEASES OF THE RETINA

DISEASES OF THE RETINADISEASES OF THE RETINA The retina is the The retina is the

innermost layer of the innermost layer of the eyeeye. . Retina consists of 10 Retina consists of 10 layers with three neurons layers with three neurons – rods, cones, bipolar – rods, cones, bipolar and ganglion cells. and ganglion cells. Grossly it may be divided Grossly it may be divided into the following into the following regions: 1) optic disc 2) regions: 1) optic disc 2) macula lutea (or the macula lutea (or the yellow spot) and 3) the yellow spot) and 3) the peripheral retina.peripheral retina.

DISEASES OF THE RETINADISEASES OF THE RETINA

Macula contains the thin Macula contains the thin sloping fovea and is made sloping fovea and is made almost entirely of cones. It is almost entirely of cones. It is the sight of detailed fine central the sight of detailed fine central vision. Ora serrata - it is the vision. Ora serrata - it is the serrated peripheral margin serrated peripheral margin where the retina ends. where the retina ends.

The The main complaintsmain complaints of the of the patients are decreasing of the patients are decreasing of the central and peripheral vision. central and peripheral vision. The retina has no sensitive The retina has no sensitive innervation therefore there is innervation therefore there is no pain in case of retinal no pain in case of retinal diseases.diseases.

Among the diseases of the retina Among the diseases of the retina the main forms are:the main forms are:

1. Retinal manifestations of systemic 1. Retinal manifestations of systemic diseases (endocrine pathology, diseases (endocrine pathology, cardiovascular diseases etc.)cardiovascular diseases etc.)

2. Inflammatory diseases2. Inflammatory diseases

3. Dystrophies and degenerations of retina3. Dystrophies and degenerations of retina

4. Tumors of retina4. Tumors of retina

The retinal changes in hypertensionThe retinal changes in hypertensionClassification of hypertensive retinal Classification of hypertensive retinal

changeschanges

1. Hypertensive angiopathy1. Hypertensive angiopathy

2. Hypertensive angiosclerosis2. Hypertensive angiosclerosis

3. Hyoertensive retinopathy3. Hyoertensive retinopathy

4. Hypertensive neuroretinopathy4. Hypertensive neuroretinopathy

Hypertensive angiopathyHypertensive angiopathyHypertensive Hypertensive

angiopathyangiopathy is is characterized by the characterized by the mild narrowing of mild narrowing of arterioles and arterioles and broadening of retinal broadening of retinal veins (correlation veins (correlation a/v=l:4 instead of a/v=l:4 instead of 2:3), irregular 2:3), irregular diameter and diameter and increased windings of increased windings of the retinal vessels.the retinal vessels.

Hypertensive angiosclerosisHypertensive angiosclerosis

Hypertensive Hypertensive angiosclerosisangiosclerosis includes includes changes of the first stage changes of the first stage and also symptoms of and also symptoms of "copper-wire" and "silver-"copper-wire" and "silver-wire" (it is an arteriolar wire" (it is an arteriolar reflex because of the reflex because of the hialinosis in the first case hialinosis in the first case and obliteration in the and obliteration in the second).second).

Hypertensive angiosclerosisHypertensive angiosclerosis Symptom of arteriovenous Symptom of arteriovenous

crossing in typical (symptom of crossing in typical (symptom of Salus-Gunn). The first grade Salus-Gunn). The first grade of this symptom is of this symptom is characterized by narrowing of characterized by narrowing of the vein on either side of the the vein on either side of the crossing. The 2d grade is crossing. The 2d grade is characterized by dilation and characterized by dilation and deviation of the vein before deviation of the vein before crossing with artery. Salus II is crossing with artery. Salus II is characterized by deflection of characterized by deflection of the vein and Salus III we can the vein and Salus III we can see a break in vein. see a break in vein.

Hypertensive retinopathyHypertensive retinopathy

Hypertensive retinopathy -Hypertensive retinopathy - consists of changes of consists of changes of previous stages plus previous stages plus haemorrhages, cotton-haemorrhages, cotton-wood spots (soft exudates), wood spots (soft exudates), and hard exudates. Also and hard exudates. Also may be retinal oedema. may be retinal oedema. The deposition of hard The deposition of hard exudates around the fovea exudates around the fovea may lead to a macular star may lead to a macular star configuration.configuration.

Hypertensive neuroretinopathyHypertensive neuroretinopathy

Hypertensive Hypertensive neuroretinopathyneuroretinopathy may present may present with symptoms of with symptoms of hypertensive retinopahty and hypertensive retinopahty and changes of the optic nerve changes of the optic nerve disc (disc swelling, flame-disc (disc swelling, flame-shaped haemorrhages at the shaped haemorrhages at the disc edge). disc edge).

Treatment: all retinal changes Treatment: all retinal changes occur due to raised blood occur due to raised blood pressure therefore first of all pressure therefore first of all we should correct blood we should correct blood pressure.pressure.

Diabetic retinopathyDiabetic retinopathy

Diabetic retinopathy (DR) is a Diabetic retinopathy (DR) is a microangiopathy affecting the retinal microangiopathy affecting the retinal precapillary arterioles, capillaries and precapillary arterioles, capillaries and

venules. venules.

Clinically,Clinically, the three main types of diabetic the three main types of diabetic retinopathy are 1) background (non-retinopathy are 1) background (non-

proliferative) DR; 2) preproliferative DR; 3) proliferative) DR; 2) preproliferative DR; 3) proliferative DR.proliferative DR.

Non-proliferative DR.Non-proliferative DR.

Venous dilation and Venous dilation and fullness, capillary fullness, capillary microaneurisms, microaneurisms, retinal haemorrhages, retinal haemorrhages, hard exudates.hard exudates.

Preproliferative DR.Preproliferative DR.

In this stage changes are In this stage changes are superadded to the superadded to the changes of non-changes of non-proliferative DR,proliferative DR, multiple multiple cotton-wool spots, blot cotton-wool spots, blot retinal haemorrhages, and retinal haemorrhages, and vascular changes (venous vascular changes (venous dilation and feading).dilation and feading).

Proliferative DR.Proliferative DR.

Neovascularization is Neovascularization is hallmark of proliferative hallmark of proliferative DR. Later on DR. Later on condensation of condensation of connective tissue around connective tissue around the vessels results in the vessels results in formation of fibrovascular formation of fibrovascular epiretinal membrane. epiretinal membrane. Vitreous detachment and Vitreous detachment and vitreous hemorrhage may vitreous hemorrhage may occur in this stage.occur in this stage.

TreatmentTreatment

1. Good diet1. Good diet 2. Antidiabetic agents for good metabolic 2. Antidiabetic agents for good metabolic

controlcontrol 3. Control of hypertension (when 3. Control of hypertension (when

associated)associated) 4. Angio- and retinoprotectors, anabolic 4. Angio- and retinoprotectors, anabolic

steroids, vitamins, enzimes (lidasa, steroids, vitamins, enzimes (lidasa, chymotrypsin), iodine drugs, antioxidants, chymotrypsin), iodine drugs, antioxidants, inhibitors of thrombocyte aggregation, inhibitors of thrombocyte aggregation, drugs reducing capillary permeabilitydrugs reducing capillary permeability

Surgical treatment.Surgical treatment.

1. Laser treatment - photocoagulation (in form of 1. Laser treatment - photocoagulation (in form of panretinal, focal coagulation) is indicated in panretinal, focal coagulation) is indicated in severe cases of preproliferative and proliferative severe cases of preproliferative and proliferative DR (it reduces retinal ischaemia)DR (it reduces retinal ischaemia)

2. Surgical treatment is required in advanced 2. Surgical treatment is required in advanced cases of proliferative DR. Vitrectomy is indicated cases of proliferative DR. Vitrectomy is indicated for dense persistent vitreous haemorrhage, for dense persistent vitreous haemorrhage, fractional retinal detachment and epiretinal fractional retinal detachment and epiretinal membrane. Associated retinal detachment also membrane. Associated retinal detachment also needs surgical repair.needs surgical repair.

Vascular disorders of the retinaVascular disorders of the retina

Retinal artery occlusionRetinal artery occlusion Patient compains of Patient compains of

sudden painless and sudden painless and profound loss of vision. profound loss of vision. Ophthalmoscopy shows Ophthalmoscopy shows the following signs - the the following signs - the retina appears white. retina appears white. Central part of the Central part of the macular area shows macular area shows cherry-red spot. Retinal cherry-red spot. Retinal arteries are narrowed. arteries are narrowed.

TreatmentTreatment is aimed at restoring the retinal is aimed at restoring the retinal circulation. circulation.

The emergency treatment should The emergency treatment should include: include: retrobulbar injection of Atropini retrobulbar injection of Atropini sulfate 0,1% intravenous, Sol. Euphyllini sulfate 0,1% intravenous, Sol. Euphyllini 2,4%, Ac. Nicotinici 1% 1,0 intramuscular. 2,4%, Ac. Nicotinici 1% 1,0 intramuscular. Inhalation of a mixture of 5% carbon Inhalation of a mixture of 5% carbon dioxide and 95% oxygen. Lowering oflOP dioxide and 95% oxygen. Lowering oflOP is necessary.is necessary.

Treatment include: Treatment include: 1) vasodilators, 2) 1) vasodilators, 2) anticoagulants, 3) steroids are indicated in anticoagulants, 3) steroids are indicated in patients with giant cell arteritis.patients with giant cell arteritis.

Retinal vein occlusionRetinal vein occlusion

It is characterized by marked It is characterized by marked sudden visual loss. Fundus sudden visual loss. Fundus examination reveals severe examination reveals severe optic disc oedema and optic disc oedema and hyperaemia. extensive hyperaemia. extensive retoinal haemorrhages retoinal haemorrhages (almost whole fundus is full (almost whole fundus is full of haemorrhages giving a of haemorrhages giving a "splashed-tomato" "splashed-tomato" appearance), engorgment appearance), engorgment and marked tortuosity of the and marked tortuosity of the retinal veins, numerous soft retinal veins, numerous soft exudates.exudates.

Retinal vein occlusionRetinal vein occlusion

Emergency treatment:Emergency treatment: 1. Control of hypertension1. Control of hypertension

2. Anticoagulants (fibrinolysin, heparin) 2. Anticoagulants (fibrinolysin, heparin) 3. Drugs improving microcirculation3. Drugs improving microcirculation

Treatment:Treatment: 1. Anticoagulants1. Anticoagulants 2. Angioprotectors2. Angioprotectors 3. Spasmolitics3. Spasmolitics 4. Steroids4. Steroids 5. Photocoagulation (to prevent neovascular 5. Photocoagulation (to prevent neovascular

glaucoma)glaucoma)

Inflammatory disorders of the Inflammatory disorders of the retinaretina

These may present as retinitis (pure retinal These may present as retinitis (pure retinal inflammation), chorioretinitis (inflammation inflammation), chorioretinitis (inflammation of retina and choroid), neuroretinitis of retina and choroid), neuroretinitis (inflammation of optic disc and surrounded (inflammation of optic disc and surrounded retina), or periphlebitis retina (inflammation retina), or periphlebitis retina (inflammation of the retinal vessels). of the retinal vessels).

Central chorioretinitisCentral chorioretinitis

Patient's Patient's complaints:complaints: dark spot in front of the eye; dark spot in front of the eye; it may presents with a sudden onset of it may presents with a sudden onset of

painless loss of vision, associated with painless loss of vision, associated with positive scotoma, positive scotoma,

micropsia and micropsia and metamorphopsia.metamorphopsia.

Central chorioretinitisCentral chorioretinitis

Ophthalmoscopy - mild Ophthalmoscopy - mild elevation of macular area, elevation of macular area, demarcated by a circular demarcated by a circular ring-reflex. Focus has a ring-reflex. Focus has a greyish colour and different greyish colour and different size. It often leaves areas of size. It often leaves areas of atrophy, depigmentation. atrophy, depigmentation. Sometimes we can Sometimes we can determine peripheral determine peripheral localization of the focus. localization of the focus. Treatment: steroids, Treatment: steroids, antibiotic, antihistamine, antibiotic, antihistamine, vitamins.vitamins.

Eales' disease (periphlebitis retinae)Eales' disease (periphlebitis retinae) It is idiopathic inflammation of the peripheral It is idiopathic inflammation of the peripheral

retinal veins. It is characterized by reccurent retinal veins. It is characterized by reccurent vitreous haemorrhages. Etiology is not known vitreous haemorrhages. Etiology is not known exactly.exactly.

The common presenting symptoms are sudden The common presenting symptoms are sudden appearance of floaters (black spots) in front of appearance of floaters (black spots) in front of the eye or painless loss of vision due to vitreous the eye or painless loss of vision due to vitreous haemorrhage. In the early stages the affected haemorrhage. In the early stages the affected veins are congested and show sheathing. In veins are congested and show sheathing. In later stages ressurent vitreous haemorrhage later stages ressurent vitreous haemorrhage may be associated with retinal may be associated with retinal neovascularization.neovascularization.

Treatment:Treatment: Oral and local steroids Oral and local steroids antitubercular traetment, vitamins. Laser antitubercular traetment, vitamins. Laser photocoagulation. photocoagulation.

Retinal detachmentRetinal detachment In retinal detachment fluid collects in the In retinal detachment fluid collects in the

potential space between the sensory retina and potential space between the sensory retina and the RPE.the RPE.

Predisposing factorsPredisposing factors of primary retinal of primary retinal detachment are high myopia, aphakia, different detachment are high myopia, aphakia, different types of retinal degenerations, trauma.types of retinal degenerations, trauma.

Clinical features.Clinical features. Patients notice a localized Patients notice a localized relative loss in the field of vision which progress relative loss in the field of vision which progress to a total loss when peripheral detachment to a total loss when peripheral detachment proceeds gradually towards the macula lutea. proceeds gradually towards the macula lutea. May be photopsia (flash of light), floaters.May be photopsia (flash of light), floaters.

Retinal detachmentRetinal detachment Ophthalmoscopy - on Ophthalmoscopy - on

examination detached examination detached retina gives grey reflex retina gives grey reflex instead of normal pink instead of normal pink reflex and is raised reflex and is raised anteriorly. These may be anteriorly. These may be small or may assume the small or may assume the shape of balloons in large shape of balloons in large bullous retinal bullous retinal detachment. The retinal detachment. The retinal blood vessels appear blood vessels appear darker than in flat retina.darker than in flat retina.

Retinal detachmentRetinal detachment

Retinal holes look Retinal holes look reddish in colour and reddish in colour and vary in shape. They vary in shape. They may be round, horse-may be round, horse-shoe shaped, slit-like. shoe shaped, slit-like.

Visual field charting Visual field charting reveals scotomas reveals scotomas corresponding to the corresponding to the area of detached area of detached retina. retina. Ultrasonography Ultrasonography confirms the diagnosis.confirms the diagnosis.

Treatment: only surgical.Treatment: only surgical.

1. Sealing of retinal breaks 1. Sealing of retinal breaks (cryocoagulation, photocoagulation or (cryocoagulation, photocoagulation or diathermy) by producing aseptic diathermy) by producing aseptic inflammation.inflammation.

2. Bringing the choroid and detached 2. Bringing the choroid and detached retina near to each other (procedure of retina near to each other (procedure of scleral buckling). An explant is a material scleral buckling). An explant is a material sutured directly onto sclera to create a sutured directly onto sclera to create a buckle.buckle.

Tumors of the retinaTumors of the retina

RetinoblastomaRetinoblastoma - it is - it is a common congenital a common congenital malignant tumor malignant tumor arising from the arising from the sensory layer of retina sensory layer of retina in one or both eyes. It in one or both eyes. It is the most common is the most common intraocular tumor of intraocular tumor of childhood. Untreated, childhood. Untreated, it is almost invariably it is almost invariably fatal. fatal.

Treatment:Treatment:

1) Enucleation (it is the treatment of 1) Enucleation (it is the treatment of choice) with postoperative choice) with postoperative rediotherapyrediotherapy

2) Tumour destructive therapy (in 2) Tumour destructive therapy (in early stages) - radiations, early stages) - radiations, photocoagulation or cryocoagulation, photocoagulation or cryocoagulation, scleral plaques containing scleral plaques containing radioisotopes.radioisotopes.