Hypertensive retinopathy.pptx

The retina is the tissue layer located in the back of your eye. This layer transforms light into nerve signals that are then sent to the brain for interpretation.

When your blood pressure is too high, the retina’s blood vessel walls may thicken. This may cause your blood vessels to become narrow, which then restricts blood from reaching the retina. In some cases, the retina becomes swollen.

Over time, high blood pressure can cause damage to th

1. Hypertensive retinopathy and retinitis pigmentosa

2. Hypertensive retinopathy IT refers to the fundus changes occurring in patients suffering from systemic hypertension The changes include 3 types 1. hypertensive retinopathy 2. hypertensive choroidopathy 3.optic neuropathy

3. Pathogenesis : 3 factors : vasoconstriction, arteriosclerotic changes , increased vascular permeability 1. vasoconstriction : arteriolar narrowing is the primary response to raised blood pressure and is related to severity of hypertension Vasoconstriction of retinal arterioles occurs in pure form in young individuals, but is affected by the pre-existing involutional sclerosis in older patients • Vasoconstriction of choroidal vessels causes choroidal and RPE ischaemia, which manifests as hypertensive choroidopathy. • Vasoconstriction of peripapillary choroid leads to optic nerve head ischaemia, manifesting as hypertensive optic neuropathy

4. 2. Arteriosclerotic changes which manifest as changes in the arteriolar reflex and A-V nipping result from thickening of the vessel wall and are a reflection of the duration of hypertension. In older patients arteriosclerotic changes may pre-exist due to involutional sclerosis. 3. Increased vascular permeability results from hypoxia and is responsible for haemorrhages, exudates, focal retinal oedema, macular oedema, focal intraretinal periarterial transudates (FIPTs), and disc oedema

5. . Clinical types Clinically, the hypertensive fundus changes can be described as: • Chronic hypertensive retinopathy, and • Malignant or acute hypertensive retinopathy. Chronic hypertensive retinopathy Patients with chronic hypertensive retinopathy are usually asymptomatic. Clinical situations in which chronic hypertensive retinopathy occurs include: 1. Hypertension with involutionary (senile) sclerosis When hypertension occurs in elderly patients (after the age of 50 years) in the presence of involutionary sclerosis the fundus changes comprise augmented arteriosclerotic retinopathy. 2. Chronic hypertension with compensatory arteriolar sclerosis This condition is seen in young patients with prolonged benign hypertension usually associated with benign nephrosclerosis. The young arterioles respond by proliferative and fibrous changes in the media (compensatory arteriolar sclerosis). Advanced fundus changes in these patients have been described as ‘ albuminuric or renal retinopathy’

6. Fundus changes of chronic hypertensive retinopathy 1. Generalized arterial narrowing or attenuation : depending upon the severity of hypertension may be mild or marked, and consists of vasoconstrictive and sclerotic phases. • Vasoconstrictive phase occurs due to diffuse vasospasm which manifests when a significant elevation of blood pressure has persisted for an appreciable period and is characterised by an increase in retinal arteriolar tone

7. . • Sclerotic phase occurs due to intimal thickening, hypoplasia of tunica media, and hyaline degeneration; and is characterised by arteriolar narrowing associated with tortuosity. 2. Focal arteriolar narrowing is seen as areas of localized vasoconstriction on the disc and within ½ disc diameter of its margin zone. 3. Arteriovenous nicking is the hallmark of hypertensive retinopathy and occurs where arteriole crosses and compresses the vein, as the vessels share a common adventitious sheath. Also known as A-V crossing changes, these include: • Salu’s sign : deflection of veins at the arteriovenous crossings, • Bonnet sign: banking of veins distal to arteriovenous crossings, • Gunn sign : tapering of veins on either side of the crossings.

8. . 4. Arteriolar reflex changes . The normal light reflex of the retinal vasculature is formed by the reflection from the interface between the blood column and vessel wall • Bright and thin, linear blood reflex is seen normally over the surface of the arteriole in the young age and is predominantly because of blood column in the arteriole, since the vessel wall is by and large transparent. • More diffuse and less bright reflex is seen due to thickening of vessel wall and represents changes of grade I and II hypertensive retinopathy. • Copper wiring , i.e., reddish-brown reflex of the arterioles occurs due to progressive sclerosis and hyalinization, and is a sign of grade III retinopathy. • Silver wiring i.e., opaque–white reflex of the arterioles occurs ultimately due to the continued sclerosis, and is seen in grade IV hypertensive retinopathy

9. . 5 . Superficial retinal haemorrhages (flame shaped) occur at the posterior pole due to disruption of the capillaries in the retinal nerve fibre layer. These haemorrhages disappear in 3 to 5 weeks. 6 . Hard exudates are lipid deposits in the outer plexiform layer of retina which occur following leaky capillaries in severe hypertensive retinopathy. They appear as yellowish waxy spots with sharp margins. They are generally seen in posterior pole and may be arranged as macular-fan or macular-star. They are also temporary and may disappear in 3–6 weeks

10. 7. Cotton wool spots are fluffy white lesions and represent the areas of infarcts in the nerve fibre layer . These occur due to ischaemia caused by capillary obliterations in severe hypertensive retinopathy. Due to their cotton wool feathery appearance they are also termed as soft exudates

11. Malignant hypertensive retinopathy Malignant hypertension is not a separate variety of hypertension, but is an expression of its rapid progression to a serious degree in a patient with relatively young arterioles undefended by fibrosis. Fundus picture is characterised by changes of acute hypertensive retinopathy, choroidopathy and optic neuropathy

12. . I. Acute hypertensive retinopathy changes include: • Marked arteriolar narrowing due to spasm of the arteriolar wall, in response to sudden rise in blood pressure. • Superficial retinal haemorrhages , flame shaped, arranged in clusters, appear in the posterior pole area due to disruption of capillaries in the nerve fibre layer. • Focal intraretinal periarteriolar transudates (FIPTs ) are small, white, focal oval lesions occurring due to the deposition of macromolecules along the major arterioles. These result due to break down of blood-retinal barrier following dilatation of terminal arterioles as a result of sudden rise in blood pressure in malignant hypertension. • Cotton wool spots are also more marked in malignant hypertensive retinopathy. • Microaneurysms, shunt vessels and collaterals may also develop as a result of capillary obliterations

13. . II.Acute hypertensive choroidopathy : • Acute focal retinal pigment epitheliopathy , characterised by focal white spots, occurs due to acute ischaemic changes in choriocapillaries . • Elschnig’s spots are small black spots surrounded by yellow halos, these are formed due to clumping and atrophy of the infarcted pigment epithelium (focal white spots) . • Siegrist streaks are formed due to linear configuration of the pigment along the choroidal arterioles. These are formed due to fibrinoid necrosis associated with malignant hypertension. • Serous neurosensory retinal detachment , which preferentially affects the macular area, may occur due to accumulation of fluid beneath the retina following breakdown of outer blood-retinal barrier owing to ischemic damage to the retinal pigment epithelium. It may also manifest as exudative bullous retinal detachment with shifting subretinal fluid

14. Elsching spots and siegrest streaks

15. III. Acute hypertensive optic neuropathy : • Disc oedema and hemorrhages on the disc and peripapillary retina which occur due to vasoconstriction of peripapillary choroidal vessels supplying the optic nerve head. The ischemia of the optic nerve head leads to stasis of axoplasmic flow, thus the lesion is a form of anterior ischaemic optic neuropathy. • Disc pallor , of variable degree, may occur late in the course of disease

16. Staging of Hypertensive Retinopathy . Keith and Wagner classification Grade I: Mild generalized arteriolar attenuation, particularly of small branches, with broadening of the arteriolar light reflex and vein concealment Grade II: Marked generalized narrowing and focal attenuation of arterioles associated with deflection of veins at arteriovenous crossings

17. Grade III: Grade II changes plus copperwiring of arterioles, banking of veins distal to arteriovenous crossings (Bonnet sign), tapering of veins on either side of the crossings (Gunn sign) and right-angle deflection of veins ( Salu’s sign). Flame-shaped haemorrhages, cotton-wool spots and hard exudates are also present . • Grade IV: All changes of grade III plus silver-wiring of arterioles and papilloedema

18. Scheie classification Staging of retinopathy changes is as follows: • Stage 0. No visible retinal abnormalities • Stage 1. Diffuse arteriolar narrowing; no focal constriction • Stage 2. More pronounced arteriolar narrowing with focal constriction • Stage 3. Focal and diffuse narrowing, with retinal haemorrhages • Stage 4. Retinal oedema, hard exudates, optic disc edema

19. Grading of the light reflex changes resulting from arteriolosclerosis is as follows: • Grade 0. Normal • Grade 1. Broadening of light reflex with minimal arteriolovenous compression • Grade 2. Light reflex changes and arteriovenous crossing changes more prominent • Grade 3. Copper-wire appearance and more prominent arteriolovenous compression • Grade 4. Silver-wire appearance and severe arteriolovenous crossing changes.

20. . Wong and McIntosh classification Mild retinopathy : generalised arteriolar narrowing, focal arteriolar narrowing, AV nicking, arteriolar wall reflex broadening. There is weak associations with stroke, coronary heart disease and cardiovascular mortality. Moderate retinopathy consists of mild retinopathy with one or more of the following signs: retinal haemorrhages (blot and dot or flame shaped) microaneurysms, cotton-wool spots, and hard exudates. There is strong association with stroke, congestive heart failure, renal dysfunction and cardiovascular mortality. Accelerated retinopathy consists of moderate retinopathy signs plus optic disc swelling , may be associated with visual loss. Associated with mortality and renal failure.

21. Management : Mild hypertensive retinopathy: blood pressure control only. Moderate hypertensive : blood pressure control , assessment of vascular risk factors (e.g., cholesterol levels) and, if indicated, risk reduction therapy (e.g., cholesterol lowering agents). Accelerated hypertensive retinopathy : urgent antihypertensive management. In such instances, physicians should aim for a small stepwise control of blood pressure over a few hours, and avoid a sudden reduction in blood pressure which may reduce perfusion of optic nerve head and central nervous system (causing stroke).

22. Pregnancy induced hypertension : Pregnancy-induced hypertension (PIH), previously known as ‘ toxaemia of pregnancy’, is a disease of unknown etiology characterised by raised blood pressure, proteinuria and generalised oedema. Retinal changes are liable to occur in this condition when blood pressure rises above 160/100 mm of Hg and are marked when blood pressure rises above 200/130 mm of Hg.

23. . Earliest changes consist of narrowing of nasal arterioles, followed by generalised narrowing. • Severe persistent spasm of vessels causes retinal hypoxia characterised by appearance of ‘cotton wool spots’ and superficial haemorrhages . • Further progression of retinopathy occurs rapidly if pregnancy is allowed to continue. • Retinal oedema and exudation is usually marked and may be associated with ‘macular star’ or ‘flat macular detachment’. Rarely, it may be complicated by bilateral exudative retinal detachment. • Prognosis for retinal reattachment is good, as it occurs spontaneously within a few days of termination of pregnancy.

24. Management : Changes of retinopathy are reversible and disappear after the delivery, unless organic vascular disease is established. • In preorganic stage when patient responds well to conservative treatment • Advent of hypoxic retinopathy (cotton wool spots, retinal oedema and haemorrhages ), however, should be considered an indication for termination of pregnancy otherwise, permanent visual loss or even loss of life (of both mother and foetus ) may occur

25. . Retinitis pigmentosa

26. Retinitis pigmentosa, primary pigmentary retinal dystrophy is a hereditary disorder predominantly affecting the rods more than the cones. Inheritance Retinitis pigmentosa (RP) may occur as: 1. Sporadic disorder, isolated without family history due to mutation of multiple gene (>50%) including rhodopsin gene (40%) 2. Inherited disorder as: • Autosomal recessive (AR), most common (25%), intermediate severity • Autosomal dominant (AD), next common (25%), least severe • X-linked (XL), least common (10%), most severe.

27. • Prevalence.: It occurs in 1 person per 5,000 of the world population. • Age. It appears in the childhood and progresses slowly, often resulting in blindness in advanced middle age. • Sex:Males are more commonly affected than females in a ratio of 3:2. • Disease is almost invariably bilateral and both eyes are equally affected

28. Pathogenesis : As a group majority of retinitis pigmentosa conditions are characterized by death of rod photoreceptors . Typical retinitis pigmentosa: rod-cone dystrophy, in which rods are degenerated early and cones are involved late

29. Clinical features : 1. visual symptoms : Night blindness due to degeneration of rods Light threshold of peripheral retina decreased Tubular vision Central vision is also lost after many years

30. 2. fundus changes : Retinal pigment changes : perivascular Jet black spots resembling bone corpuscles Initially these changes found in equatorial region later spreads to anteriorly and posteriorly Thinning and atrophy of RPE in mid and far periphery with relative sparing in macula Pale and waxy optic disc  consecutive optic atrophy Colloid bodies, choroidal sclerosis, cystoid macular edema , atrophic and cellophane maculopathy is seen

31. 3.visual field changes : Annular or ring shaped scotoma

32. 4 . electrophysiological changes : ERG: initially subnormal, B wave affected before A wave EOG: subnormal with absence of light peak

33. . Associations of retinitis pigmentosa I. Ocular associations. These include myopia, primary open-angle glaucoma, microphthalmos, conical cornea (keratoconus) and posterior subcapsular cataract. II. Systemic associations. Most cases of retinitis pigmentosa (RP) are isolated (i.e., with no systemic features), but about 25% have associated systemic diseases. A number of specific syndromes are described: 1. Laurence-Moon-Biedl syndrome: It is characterised by retinitis pigmentosa, obesity, hypogenitalism , polydactyly and mental deficiency. 2. Cockayne’s syndrome: It comprises retinitis pigmentosa, progressive infantile deafness, dwarfism, mental retardation, nystagmus and, ataxia

34. . 3. Refsum’s syndrome: It is characterised by retinitis pigmentosa, peripheral neuropathy and cerebellar ataxia. 4. Usher’s syndrome: It includes retinitis pigmentosa and labyrinthine deafness. 5. Hallgren’s syndrome: It comprises retinitis pigmentosa, vestibulocerebellar ataxia, congenital deafness and mental deficiency. 6. Other associated syndromes include Bussen – Koranzweig syndrome ( Abetalipoproteinaemia ), Kearns-Sayer syndrome, Friedreich’s ataxia, Bardet- Biedle syndrome, NARP (neuropathy, ataxia, and retinitis pigmentosa), neuronal ceroid lipofuscinosis, and olivopontocerebellar degeneration

35. . Atypical forms of retinitis pigmentosa 1 . Cone-rod dystrophy . In this condition, cones are degenerated earlier and more severely than the rods. • Central vision is reduced, • Colour vison is defective, • Defective vision in bright light Fundus examination shows macular lesions with or without peripheral changes. 2. Retinitis pigmentosa sine pigmento . It is characterised by all the clinical features of typical retinitis pigmentosa, except that there are no visible pigmentary changes in the fundus. 3. Sectorial retinitis pigmentosa . It is characterized by involvement of only one sector of the retina.

36. 4 . Pericentric retinitis pigmentosa . In this condition, all the clinical features are similar to typical retinitis pigmentosa except that pigmentary changes are confined to an area, immediately around the macula. 5. Retinitis punctata albescens . It is characterised by the presence of innumerable discrete white dots scattered over the fundus without pigmentary changes. Other features are narrowing of arterioles, night blindness and constriction of visual fields

37. Treatment : Treatment no effective treatment for the disease. 1. Measures to stop progression, : vasodilators, placental extracts, transplantation of rectus muscles into suprachoroidal space, light exclusion therapy, ultrasonic therapy and acupuncture therapy. Recently vitamin A (15000 IU, PO, qd of palmitate form) has been recommended to check its progression. 2. Correct any refractive error, prescribe glasses. 3. Systemic acetazolamide (500 mg po) for associated cystoid macular oedema. 4. Low vision aids (LVA) in the form of ‘magnifying glasses’ and ‘night vision device’ may be of some help. 5. Rehabilitation of the patient should be earned out as per his socioeconomic background. 6. Prophylaxis.Genetic counselling for no consanguinous marriages may help to reduce the incidence of disease. Further, affected individuals should be advised not to produce children.