Hypertensive retinopathy

Published on 02/04/2015 by admin

Filed under Internal Medicine

Last modified 22/04/2025

Print this page

rate 1 star rate 2 star rate 3 star rate 4 star rate 5 star
Your rating: none, Average: 0 (0 votes)

This article have been viewed 2103 times

202 Hypertensive retinopathy

Instruction

Examine this patient’s eyes.

Examine this patient’s fundus.

Salient features

History

• Usually no ocular symptoms

• History of hypertension.

Examination

• Arteriovenous nipping (Fig. 202.1)

• Arteriolar narrowing

• Macular star

• Flame-shaped and blot haemorrhages (see Fig. 201.3B)

• Cottonwool exudates (see Fig. 201.3D)

• Papilloedema may or may not be present (Fig. 202.2).

image

Fig. 202.1 (A) Mild retinopathy in an eye with ischaemic optic neuropathy. (B) Severe hypertensive retinopathy. CWS, cotton-wool spots; FH, flame-shaped retina haemorrhage; DS, swelling of the optic disc; AVN, arteriovenous nipping.

(With permission from Wong, Mitchell 2007.)

image

Fig. 202.2 (A) Grade 1: early and minor changes include increased tortuosity of a retinal vessel and increased reflectiveness (silver wiring) of a retinal artery (at 1 o’clock in this view). (B) Grade 2: increased tortuosity and silver wiring (arrowheads) plus ‘nipping’ of the venules at arteriovenous crossings (arrow). (C) Grade 3: as grade 2 plus flame-shaped retinal haemorrhages and soft ‘cotton-wool’ exudates. (D) Grade 4: swelling of the optic disc (papilloedema), retinal oedema and hard exudates around the fovea, producing a typical ‘macular star’.

(With permission from Forbes, Jackson 2003.)

Proceed as follows:

• Tell the examiner that you would like to:

• check the BP
• examine the urine for proteinuria
• examine the heart for left ventricular hypertrophy.

Diagnosis

This patient has flame-shaped haemorrhages with a macular star (lesions) caused by hypertension (aetiology).

Advanced-level questions

How would you grade hypertensive retinopathy?

Keith–Wagener–Barker classification

This combines the clinical findings of hypertension and atherosclerosis:

• Stage I: arteriolar narrowing

• Stage II: irregular calibre of arterioles

• Stage III: cottonwool exudates; flame and blot haemorrhages, retinal oedema

• Stage IV: papilloedema.

Note: Subsequent studies have shown that the clinical features and prognosis of patients with stage III and stage IV disease were similar whether or not papilloedema was present; consequently the terms ‘malignant’ and ‘accelerated’ could be used interchangeably. Instead ‘hypertensive crisis’ is used to refer to the syndrome of raised BP complicated by end-organ damage (e.g. stroke, renal failure, myocardial ischaemia or infarction, stage III or IV hypertensive retinopathy).

Scheie classification

This separates the clinical findings of hypertension and atherosclerosis (Arch Ophthalmol 1953;49:117–38) (Fig. 202.2).

• Hypertension:

Grade 0: no changes
Grade 1: barely detectable arteriolar narrowing
Grade 2: obvious arteriolar narrowing with focal irregularities
Grade 3: grade 2 plus retinal haemorrhages and/or exudates
Grade 4: grade 3 plus papilloedema.

• Arteriolar sclerosis:

Grade 0: normal
Grade 1: barely detectable light reflex changes
Grade 2: obvious increased light reflex changes
Grade 3: copper-wire arterioles
Grade 4: silver-wire arterioles.

What is the significance of retinal arteriolar narrowing in normotensive individuals?

Retinal arteriolar narrowing might also be used to predict subsequent development of hypertension in individuals initially classified as normotensive (BMJ 2004; 329:79).

Mention some causes of cottonwool spots

• HIV infection per se

• Anaemias

• Infective endocarditis

• Leukaemias

• Diabetic retinopathy (p. 699).

Mention a few causes of hypertension

• In 90%, it is essential hypertension with no underlying cause and this may represent the ‘normal’ spread

• In 10%, there is an underlying cause:

• Renal: renal artery stenosis, polycystic kidneys, chronic glomerulonephritis, polyarteritis nodosa, chronic pyelonephritis
• Endocrine: Cushing syndrome, Conn syndrome, phaeochromocytoma, acromegaly, diabetes mellitus
• Eclampsia and pre-eclamptic toxaemia of pregnancy
• Coarctation of the aorta.

How would you investigate a patient with hypertension?

• Urine for protein, glucose, casts

• Midstream urine for microscopy and culture

• Urea and electrolytes, fasting lipids

• Chest radiography

• ECG

• Urine catecholamines

• Intravenous pyelography

• Renal artery digital subtraction angiography (DSA).

What is the relationship between morbidity and hypertensive retinopathy?

Neurological link

• In a 3-year population-based cohort study of atherosclerosis risk, incident stroke events were more common in participants with signs of hypertensive retinopathy than in participants without retinopathy. When controlled for BP, diabetes, lipids and other risk factors, moderate signs of hypertensive retinopathy (cotton-wool spots, retinal haemorrhages and microaneurysms) were associated with a two- to four-fold higher risk of incident stroke. Weaker associations between signs of mild hypertensive retinopathy and risk of stroke were also present (Lancet 2001; 358:1134–40).

• Hypertensive retinopathy is also reported to be associated with cognitive decline, cerebral white-matter lesions identified by cerebral MRI, lacunar infarctions, cerebral atrophy and stroke mortality.

Cardiovascular link

• Studies of the association between hypertensive retinopathy signs and heart disease have produced inconsistent results. However, hypertensive retinopathy has been linked with coronary artery stenosis and with incident coronary heart disease events.

• Some investigators suggest that moderate hypertensive retinopathy could be used to predict incident congestive heart failure, even in individuals without a previous history of myocardial infarction.

Other links

• Retinopathy signs is also associated with indicators of target organ damage, such as microalbuminuria and renal impairment and left ventricular hypertrophy.

What are Elschnig’s spots?

They are black flecks surrounded by yellow or red halos and occurs in advanced hypertensive retinopathy. They are caused by focal occulsion of the choroidal capillaries, which leads to necrosis and atrophy of retinal pigment epithelium. Acutely, these spots are punctuate tan-white lesions that leak on fluorescein angiography through breakdown in the blood–brain barrier.

How would you treat hypertension?

• Salt restriction

• Advise the patient to stop smoking

• First-line drug therapy:

• In women and smokers: bendroflumethiazide
• In non-smoking men: beta-blockers.

Further reading

Ahmed ME, Walker JM, Beevers DG, Beevers M. Lack of difference between malignant and accelerated hypertension. BMJ. 1986;292:235-237.

Dollery CT, Ramalho PS, Patterson JW, et al. Retinal microemboli: experimental production of ‘cottonwool’ spots. Lancet. 1965;i:303.

Keith NM, Wagner HP, Barker NW. Some different types of essential hypertension: their course and prognosis. Am J Med Sci. 1939;197:332-343.

Anton Elschnig (August 22, 1863–1939) was an Austrian opthalmologist.

Marcus Gunn first described hypertensive retinopathy in the 19th century in a series of patients with hypertension and renal disease (Trans Ophthalmol Soc UK 1892;12:124–5).

In 1939, Keith, Wagner and Barker showed that the signs of retinopathy were predictive of death in patients with hypertension (Am J Med Sci 1939;197:332–43).

Share this:

Related posts:

Default ThumbnailSixth cranial nerve palsy Osteoarthrosis Infective endocarditis Default ThumbnailAddison’s disease Default ThumbnailUraemia Fibrosing alveolitis