Hypertensive retinopathy
Encyclopedia
Hypertensive retinopathy is damage to the retina
due to high blood pressure
(i.e. hypertension
).
Subjected to excessively high blood pressure over prolonged time, the small blood vessels that involve the eye
are damaged, thickening, bulging and leaking.
Early signs of retinopathy correlate less well with mortality and morbidity than used to be thought, but signs of accelerated or "malignant" hypertension indicate severe illness.
or headache
s.
Grade 2
Grade 3
Grade 4
There is an association between the grade of retinopathy and mortality. At 3 years 70% of those with grade 1 retinopathy will be alive whereas only 6% of those with grade 4 will survive. Grading of the retinopathy is thus important as the hypertensive process will be affecting small vessels throughout the body in a similar manner. (The retina is simply the most visible area to assess.)
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
due to high blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
(i.e. hypertension
Hypertension
Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...
).
Pathophysiology
The retina is one of the "target organs" that are damaged by sustained hypertension.Subjected to excessively high blood pressure over prolonged time, the small blood vessels that involve the eye
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...
are damaged, thickening, bulging and leaking.
Early signs of retinopathy correlate less well with mortality and morbidity than used to be thought, but signs of accelerated or "malignant" hypertension indicate severe illness.
Symptoms
Most patients with hypertensive retinopathy present without visual symptoms, however, some may report decreased visionVisual perception
Visual perception is the ability to interpret information and surroundings from the effects of visible light reaching the eye. The resulting perception is also known as eyesight, sight, or vision...
or headache
Headache
A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...
s.
Signs
Signs of damage to the retina caused by hypertension include:- ArterioscleroticArteriosclerosisArteriosclerosis refers to a stiffening of arteries.Arteriosclerosis is a general term describing any hardening of medium or large arteries It should not be confused with "arteriolosclerosis" or "atherosclerosis".Also known by the name "myoconditis" which is...
changes- Arteriolar narrowing that is almost always bilateral. (The following grading system is specific to the degree of the arteriolar narrowing only. See later for the grading of hypertensive retinopathy as a whole.)
- Grade I - 3/4 normal caliber
- Grade II - 1/2 normal caliber
- Grade III - 1/3 normal caliber
- Grade IV - thread-like or invisible
- Arterio-venous crossing changes (aka "AV nickingAV nickingAV, or arteriovenous nicking is the phenomenon where, on ophthalmologic examination, an arteriole is seen crossing a venule resulting in impaction of the vein with bulging on either side of the crossing...
") with venous constriction and banking - Arteriolar color changes
- Copper wire arterioles are those arterioleArterioleAn arteriole is a small diameter blood vessel in the microcirculation that extends and branches out from an artery and leads to capillaries.Arterioles have muscular walls and are the primary site of vascular resistance...
s in which the central light reflex occupies most of the width of the arteriole - Silver wire arterioles are those arterioleArterioleAn arteriole is a small diameter blood vessel in the microcirculation that extends and branches out from an artery and leads to capillaries.Arterioles have muscular walls and are the primary site of vascular resistance...
s in which the central light reflex occupies all of the width of the arteriole
- Copper wire arterioles are those arteriole
- Vessel sclerosisSclerosis (medicine)In medicine, sclerosis refers to the stiffening of a structure, usually caused by a replacement of the normal organ-specific tissue with connective tissue.Types include:...
- Arteriolar narrowing that is almost always bilateral. (The following grading system is specific to the degree of the arteriolar narrowing only. See later for the grading of hypertensive retinopathy as a whole.)
- IschemicIschemiaIn medicine, ischemia is a restriction in blood supply, generally due to factors in the blood vessels, with resultant damage or dysfunction of tissue. It may also be spelled ischaemia or ischæmia...
changes (e.g. "cotton wool spotsCotton wool spotsCotton wool spots are an abnormal finding on funduscopic exam of the retina of the eye. They appear as puffy white patches on the retina. They are caused by damage to nerve fibers. The nerve fibers are damaged by swelling in the surface layer of the retina...
") - Hemorrhages, often flame shaped.
- EdemaEdemaEdema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
- Ring of exudateExudateAn exudate is any fluid that filters from the circulatory system into lesions or areas of inflammation. It can apply to plants as well as animals. Its composition varies but generally includes water and the dissolved solutes of the main circulatory fluid such as sap or blood...
s around the retina called a "maculaMaculaThe macula or macula lutea is an oval-shaped highly pigmented yellow spot near the center of the retina of the human eye. It has a diameter of around 5 mm and is often histologically defined as having two or more layers of ganglion cells...
r star"
- Ring of exudate
- PapilledemaPapilledemaPapilledema is optic disc swelling that is caused by increased intracranial pressure. The swelling is usually bilateral and can occur over a period of hours to weeks. Unilateral presentation is extremely rare....
, or optic discOptic discThe optic disc or optic nerve head is the location where ganglion cell axons exit the eye to form the optic nerve. There are no light sensitive rods or cones to respond to a light stimulus at this point. This causes a break in the visual field called "the blind spot" or the "physiological blind spot"...
edemaEdemaEdema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
, in patients with malignant hypertensionMalignant hypertensionMalignant hypertension or hypertensive emergency is severe hypertension with acute impairment of an organ system and the possibility of irreversible organ-damage... - Visual acuityVisual acuityVisual acuity is acuteness or clearness of vision, which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain....
loss, typically due to macular involvement
Grades
Grade 1- Generalised arteriolar constriction - seen as `silver wiring` and Vascular tortuosities.
Grade 2
- As grade 1 + irregularly located, tight constrictions - Known as `AV nicking` or `AV Nipping`
Grade 3
- As grade 2 + with cotton wool spots and flame-haemorrhages
Grade 4
- As above but with swelling of the optic disk (papillodema)
There is an association between the grade of retinopathy and mortality. At 3 years 70% of those with grade 1 retinopathy will be alive whereas only 6% of those with grade 4 will survive. Grading of the retinopathy is thus important as the hypertensive process will be affecting small vessels throughout the body in a similar manner. (The retina is simply the most visible area to assess.)
Differential Diagnoses
- Diabetic Retinopathy
- Collagen Vascular Disease
- Anemia
- Radiation Retinopathy
- Central Retinal Vein Occlusion
Treatment and management
A major aim of treatment is to prevent, limit, or reverse such target organ damage by lowering the patient's high blood pressure. Anti-hypertensive treatment plays a major role in reversing the retinal changes. The eye is an organ where damage is easily visible at an early stage, so regular eye examinations are important.See also
- Hypertensive crisis
- List of eye diseases and disorders
- List of systemic diseases with ocular manifestations
- OphthalmologyOphthalmologyOphthalmology is the branch of medicine that deals with the anatomy, physiology and diseases of the eye. An ophthalmologist is a specialist in medical and surgical eye problems...
- OptometryOptometryOptometry is a health care profession concerned with eyes and related structures, as well as vision, visual systems, and vision information processing in humans. Optometrists, or Doctors of Optometry, are state licensed medical professionals trained to prescribe and fit lenses to improve vision,...