Protect your eyes

How can diagnose type of hypertension from eye examination

noreply@blogger.com (Sea) — Sun, 29 May 2011 19:01:00 +0000

You can easily know if the patient has acute or chronic hypertension through.

Signs of Acute hypertension crisis

1) Choroidopathy :

Elschning spots small black spots surrounded by yellow hallos which represent focal choroidal infarcts.

Siegrist streaks flecks arrange of linearly infarcts along choroidal vessels indication of fibroid necrosis.

2) Retina:

cotton wool spots
Exudative retinal detachment bilateral may occure in toxaemis of pregnancy.

3) Optic disc:

can see sign of papilloedema.

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Macular function

noreply@blogger.com (Sea) — Wed, 25 May 2011 17:33:00 +0000

Macular function with clear

Visual acuity
Pupillary reaction.
Colour vision test.
Ophthalmoscopy.
Slit lamp biomicroscopy.
Amsler grid test .
Photostress test.

Macular test with opaque

Perception of light (pL).
Pupillary reaction.
Colour differeniation.
Non verbal vision test.
Maddox rod test.
Disc with multiple perforations (2 pinholes).
ERG .

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The methods of assessment of the ocular blood flow

noreply@blogger.com (Sea) — Tue, 24 May 2011 18:14:00 +0000

A) The technique used in experiment animal:

Intravascular microsphere injection.
hydrogen clearance.
Krypton washout.
labile liposomes.

B) Flurescenin fundus angiography and ICG angiography.

Pulsatile ocular blood flow calculations.
Doppler color imaging.

Blue – field entoptometry .
laser Doppler velocimetry a flowmetry.
MRI.

Result:

Blow flow value in retina 35 – 80 lit /mi.
Mean retinal circulate time 3 – 5 sec.
60% of O2 & 75% glucose need by Retina provid by cheroidal circulation.
the different in O2 tension in art-venous blood in retina is 38% while in choroid < 10%.

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Arteriosclerosis

noreply@blogger.com (Sea) — Mon, 23 May 2011 21:18:00 +0000

It is the presence of changes at A-V crossings ( AV nipping ).
It is not indicative of severity of hypertension but indicative for long time ( many years ).

Grad 1 Subtle broadening of the arteriolar light reflex mild

generalized arteriolar attenuation.

Grad 2 Obvious broadening of the arteriolar light reflex and deflection of veins of A-V crossings ( Salus sign ) .

Grad 3 copper wiring of arteriolar :

banking of veins distal to AV crossings ( Bonnet sign )
tapering of veins on both sides of crossing ( Gunn sign ) and right – angled deflection of veins

Grad 4 Silver wiring of arteriolar + grad 3 Changes.

Source : Kanski.

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Hypertensive Retinopathy

noreply@blogger.com (Sea) — Mon, 23 May 2011 17:55:00 +0000

The response of retinal arterioles to systemic hypertensive include :

1- Vasoconstriction:

hypertensive narrowing is seen in its pure form only in young patients.

2- Disruption of inner blood – retinal barrier :

leading to increase vascular permeability causing:

flame – shaped retinal hemorrhage.
retinal oedema.
hard exudate.

Grad of hypertension changes :

Grad 1     Generalized arteriolar a attenuation.

Grad 2     Grad 1 + focal arteriolar a attenuation.

Grad 3     Grad 2 + cotton wool spots , flam

                 shaped hemorrhage chronic retinal oedema.

Grad 4     Grad 3 + disc swelling + macular star.

3- Arteriosclerosis.

Source : Kanski.

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Systemic Hypertension effect on eye

noreply@blogger.com (Sea) — Sun, 15 May 2011 22:05:00 +0000

Hypertension

is one of the commonest diseases in the world, affect up to 60% of those aged over 60 years old.

The majority of HTN is chronic, unknown cause ( essential ).

HTN mean increase systemic blood pressure > 140 / 90 mmHg.

Ophthalmic features include:

Retinal arteriolosclerosis.
Branch retinal vein occlusion.
Retinopathy.
Retinal artery occlusion.
Retinal artery macro aneurysm.
Anterior ischemic optic neuropathy.
Choroidal infarcts.
ocular motor nerve palsies.
Exudative retinal detachment ( with eclampsia ).

The differential diagnosis of Coats disease

noreply@blogger.com (Sea) — Wed, 11 May 2011 19:28:00 +0000

Is similar to the differential diagnosis of leukocoria (which is extensive).

It includes:

retinoblastoma.
persistent fetal vasculature (PFV).
retinopathy of prematurity.
rhegmatogenous.

exudative, or tractional retinal detachment.
ocular toxocariasis.
familial exudative vitreoretinopathy (FEVR).
retinal capillary hemangiomatosis (Von Hippel-Lindau disease).
cataract.
glaucoma.
uveitis; vitreous hemorrhage.
colobomas of the choroid and optic disc.
Leber miliary aneurysm disease is an early or nonprogressive form of Coats disease.

Main lines of treatment of coats disease

noreply@blogger.com (Sea) — Wed, 11 May 2011 19:23:00 +0000

The disease does not respond to steroid or antibiotic treatment.

Recommended treatments depend mainly on the stage of the disease,

and they include:

observation,
laser photocoagulation,
cryotherapy,
retinal detachment repair with pars plana vitrectomy and/or scleral buckle,

and enucleation.
Because treatment involves general anesthesia and frequent follow-up,
discussions with a patient's parents (if the patient is a minor) regarding diagnosis, prognosis, and treatment goals are of extreme importance.
Laser treatment has been used with a high success rate in cases with less exudation. Treatment is directed to areas of vascular leakage and nonperfusion, which decreases or eliminates further exudation and leads to resolution of the exudates and serous detachment. Fluorescein angiography is very useful in guiding laser treatment.
Peripheral lesions are better treated with cryotherapy or a combination of laser and cryotherapy.
Treatment may have to be repeated, as recurrences may follow.
In more advanced cases, drainage of the subretinal fluid may be necessary, with or without the use of a scleral buckle. Pars plana vitrectomy has been recently used to treat exudative and tractional retinal detachments.
Despite the resolution of exudates, subretinal fibrosis and scarring may limit the visual prognosis. Because the disease is unilateral in most cases, patients can live a normal life with the use of polycarbonate glasses for protection of the fellow eye, especially during sports activities.

Associated complications of Coats disease include:

neovascular glaucoma (approximately 10% of patients),
angle closure glaucoma,
anterior chamber cholesterolosis (3%).
retinal/disc neovascularization.
vitreous hemorrhage.
secondary retinal vasoproliferative tumor.
intraretinal cysts.
In this patient, enucleation was the preferred treatment because of the poor visual prognosis.

Clinical Finding in Coats Disease

noreply@blogger.com (Sea) — Wed, 11 May 2011 18:38:00 +0000

Clinically, Coats disease presents with:

decreased vision.
strabismus.
leukocoria.

(white pupillary reflex or cats eye reflex), and redness.

It may, however, be detected incidentally

It is not generally associated with pain, except for in advanced cases with secondary associated neovascular glaucoma.

It has not been associated with infectious or inflammatory conditions, and the great majority of patients have no associated systemic medical problems.

The clinical presentation shows gr

eat variability.

Typically, the ophthalmoscopic examination

reveals:

A localized area of subretinal exudates associated with vascular abnormalities.
Vascular changes may include peripheral retinal telangiectasia, capillary and small vessel dilatation and tortuosity, sheathing, capillary nonperfusion, and small aneurysms located at the equator of the eye and the ora serrata (most commonly, inferotemporal).
The posterior pole is less frequently affected.
Exudation is a common feature that presents in most cases as flat intraretinal and subretinal exudates. These exudates initially appear in areas of telangiectasia and progress to become more widespread.
Macular protein accumulation can occur directly from macular telangiectasia or indirectly from peripheral disease.
A dense exudate or white nodule in the macula can progress to a disciform lesion that indicates
a poor visual prognosis.
Retinal hemorrhages may be seen.
The vitreous remains clear until the advanced stages.
Retinal cysts may be seen and are common in chronic retinal detachments of different etiologies.

The diagnosis may be suspected clinically by:

Ancillary testing is extremely helpful to differentiate Coats disease from retinoblastoma.
Intravenous fluorescein angiography helps to visualize the telangiectatic vessels as irregular dilated tortuous vessels filling in the late arterial and early venous phases. Microaneurysms are seen as "lightbulb aneurysms". The angiogram will also show progressive leakage from abnormal vessels, adjacent areas of capillary dropout, and late staining of intraretinal exudates.

Based on the clinical appearance and progression, Coats disease may be classified in 5 grades, as follows:

Grade I: Isolated focal exudates.
Grade II: Massive elevated exudation.
Grade III: Partial retinal detachment.
Grade IV: Total retinal detachment.
Grade V: Secondary complications.

A more recent classification system has emerged, which is based on the prognosis. It grades the disease in the following manner:

Grade I: Telangiectasias only.
Grade II: Telangiectasias and exudation.
Grade III: Exudative retinal detachment.
Grade IV: Total retinal detachment with secondary glaucoma.
Grade V: End-stage disease.

What is Coats disease ?

noreply@blogger.com (Sea) — Wed, 11 May 2011 18:20:00 +0000

Coats Disease:

Is a rare idiopathic retinal condition, in which abnormal telangiectatic retinal vessels cause intra- and subretinal exudates and retinal detachment.

Figure 1.

Figure 2.

It typically occurs unilat

erally in children, and most commonly in young boys. Males account for approximately 80% of cases. Adults and adolescents may be affected as well.

The mean age at diagnosis is 5 years. It may be seen as early as 1 month of age, and most cases are diagnosed before the age of 10 years.

The severity of the condition is worse in younger patients (especially those younger than age 3 years), in whom the disease progresses more rapidly.

Coats disease has a sporadic occurrence.

Diabetic Retinopathy and pregnancy

noreply@blogger.com (Sea) — Tue, 10 May 2011 18:24:00 +0000

Pregnancy associated with rapid progress of D.R.

Stages of retinopathy in first trimester : if

No retinopathy can develop 10% BDR.
Mild BDR can develop 20% moderate or worse BDR.
moderate to sever BDR will develop 25% BDR.
diabetic maculopathy resolve spontaneous after pregnancy don't need if develop late in pregnancy.

Predicating factors include:

poor control before pregnancy.
Too rapid control during early stage of pregnancy.
Development of pre eclampsia.

so the diabetic woman should achieved good control before conception, and monthly screening.

Pregnant patient can do FL angiography it hasn't terotogenic effect but ICG can't do.

It can do laser for treatment of DR without fear.

Diabetic Retinopathy

noreply@blogger.com (Sea) — Tue, 10 May 2011 18:22:00 +0000

How to protect yourself from Diabetic Retinopathy ?

1-screening

all diabetic patients aged over 12 years and / or entering puberty in type 1 (IDDM) should be screened or once diagnose in type 2 (NIDDM).

Annual review is should be

done including measuring of visual acuity , fundus examination. following pupillary dilation.

2-good control of diabetes:

can prevent or delay development.

3-Avoid hypertension:

should be tightly controlled (140 / 80 mmHg)

4-Avoid risk factors

( which exaggerate effect of D.R.)

obesity or increase body mass .
hypertension.
anemia.
smoking.
hyperlipidemia.
Nephropathy if sever associated with

worsening of Diabetic Retinopathy.

Anatomy of the eye

noreply@blogger.com (Sea) — Tue, 10 May 2011 17:19:00 +0000

eye :

One of the most precious organ in human body . the eyelid and bony orbit act as a protective barrier . let’s take a small overview about the eye ball.

it consist of …..

conjunctiva:

A transparent sheet surround the eye ball back of the eyelids up & down, fornixes lateral and medial.

cornea:

A transparent part, one of the most important mechanism in the clarity and good vision.

sclera:

Whitish part surround eyelid, consist mainly from collagenous, fibrosis tissues to protect inner parts of the eye.

iris:

The color part which the color of the eye it was usually genetically dependence usually the infant born with grayish color then change this color during first year of the life.

lens:

A transparent elastic organ it form with the cornea a good refractive system to see clear from different distance.

retina:

A transparent, it receive the light convert it to electrical sight go through optic nerve to cerebral cortex.

choroid:

Vascular layer between sclera, retina it mainly give the blood supply to inner part of the eye.

Aqueous , vitreous:

Occupied anterior , posterior chamber they keep the pressure , shape of the eye.

Ciliary Body:

It responsible for aqueous formation and movement of the lens zonules.