DIABETIC RETINOPATHY

NEED OF SPECIALIZED EYE CARE FOR DIABETICS

Latest pattern scan PASCAL Laser, SLO-OCT & Anti-VEGF Treatment

Diabetes Mellitus (Sugar disease) is a common community health problem. From an estimated 30 million patients in India alone in year 2000, the figure increased to 62 million (6.2 crore) cases by the year 2011 and is expected to cross 100 million by the year 2030. The risk of blindness is about 25 times more in a diabetic patient than of a same age non-diabetic patient. Since there is no pain or redness in the eye, the diabetic patient is mostly unaware of the complications developing inside the eye till suddenly he/she notices a marked loss of vision.

The three most affected tissues are those of the kidney (nephropathy), nerves (neuropathy) and the retina (parda) of the eye (retinopathy). When all three complications occur in the same patient it is called diabetic triopathy.

Sight threatening complications occur in a large number of diabetics and these if not diagnosed and treated in time can lead to permanent blindness.

Diabetes may affect the eyes in many ways

SYMPTOMS

  • Frequent change in the number of glasses.
  • Increased risk of Cataract (Safed Motia): 2 to 4 times greater chances than normal people.
  • More chances of developing Glaucoma (Kala Motia).
  • Higher risk of eye infections like Corneal Ulcers or infection following any eye surgery.
  • Paralysis of external eye nerves causing squint with double vision.
  • Development of a scotoma or shadow in your field of view
  • Blurry and/or distorted vision
  • Corneal abnormalities such as slow healing of wounds due to corneal abrasion
  • Near vision problems unrelated to presbyopia
  • Diabetic Retinopathy

Diabetic Retinopathy

This is one of the most serious eye complications of diabetes. It causes swelling and bleeding in the Retina (Parda) of the eye along with growth of abnormal new blood vessels which cause more complications. The damage is frequently permanent and hence needs prompt treatment. About one-fifth (20%) of all adults found to diabetic for the first time have already developed this complication.

By twenty years of the disease nearly 100% of patients with Type I diabetes (childhood onset type) and 60% of Type II diabetes (adult onset type) have developed this complication

TYPES OF DIABETIC RETINOPATHY

1. The stage of disease before neo-vascularisation has occurred is called “Background Retinopathy” or BDR / Non-Proliferative Diabetic Retinopathy or NPDR.

There can be extensive visual loss in this stage also, in case of swelling of the centre of the retina (Macular Edema, CSME) .Fine blood vessels that leak fluids and lipids in centre of retina to form hard exudates thereby causing vision loss .

NORMAL RETINA PHOTO
NPDR
NPDR with CSME

2. Once neo-vascularisation (formation of new abnormal blood vessels) has developed the disease is said to have entered the stage of “Proliferative diabetic Retinopathy” or PDR. The risk of sudden visual loss due to bleeding from new abnormal fragile retinal vessels inside the eye (pre-retinal or vitreous hemorrhage) is quite high in this stage.These abnormal blood vessels grow scar like tissue with them which may pull the retina away causing tractional Retinal detachment .

Management

There are three major treatments for diabetic retinopathy, which are very effective in reducing vision loss from this disease.

  • Laser treatment
  • Intravitreal Injection / implant of corticosteroids into the eye, and Intravitreal Injection of anti-VEGF agents into the eye. Although these treatments are very successful (in slowing or stopping further vision loss), they do not cure diabetic retinopathy. INTRAVITREAL Injection of triamcinolone or anti-VEGF drugs in some patients results in a marked increase of vision, especially if there is an edema of the macula.
  • Vitrectomy / Vitreo-Retinal Surgery
  • Avoiding tobacco use and correction of associated hypertension are important therapeutic measures in the management of diabetic retinopathy.
  • Like diabetes itself, diabetic retinopathy once developed needs life long care and management and can never be completely cured but it can be controlled with proper care. There is no permanent medical (drug) treatment of this complication. A strict control of blood sugar level along with strict control of lipid profile and B.P. however is beneficial.

DIABETIC EYE TESTS / DIAGNOSIS

Diabetic retinopathy is detected during an eye examination that includes:

  • 1. Visual acuity test: This test uses an snellen visual chart to measure how well a person sees at various distances
  • 2. Pupil dilation: This allows to examine more of the retina and look for signs of diabetic retinopathy. After the examination, close-up vision may remain blurred for several hours.
  • 3. Ophathalmoscopy: Ophthalmoscopy is an examination of the retina in which an eye care professional takes detailed view of Retina.
  • 4. Slit Lamp Biomicroscopy Retinal Screening, Fundus Photo is used for the early detection of diabetic retinopathy The doctor will look at the retina for early signs of the disease, such as :
    • Leaking blood vessels,
    • Retinal swelling, such as macular edema,
    • Pale, fatty deposits on the retina (exudates) – signs of leaking blood vessels,
    • Damaged nerve tissue (neuropathy)and
    • Any changes in the blood vessels.

    If macular edema is suspected, FFA and sometimes OCT may be performed.


    • 5. Fundus Fluorescein Angiography (FFA) & ImageNet system:
  • In FFA a fluorescent dye is injected into the vein of the arm and rapid photographs of the blood circulating inside the retina (parda) of the eye are taken. This is an imaging technique which relies on the circulation of Fluorescein dye to show staining, leakage, or non-perfusion of the retinal and choroidal vasculature .

    • Fundus fluorescein images

6. Optical Coherence Tomography (OCT)

This produces an optical cross sectional images of the retina which can be used to measure the thickness of the retina and to resolve and analyze its major layers, allowing the observation of swelling.

Laser or other Diabetic Retinopathy treatment is undertaken after fundus test and other advanced tests available here like the latest Spectral OCT-SLO (that is OCT Optical Coherence Tomography) with (SLO Scanning Laser Ophthalmoscope).

SPECTRAL OCT - SLO IMAGES

To confirm diagnosis, to know the extent of damage ,to plan treatment schedule and to record various changes for future reference we suggest a fluorescein angiogram and OCT.

TREATMENT

The most effective treatment is by LASER photocoagulation and / or by various injections inside the eye.

1. PHOTOCOAGULATION LASERS

Laser machines emit a special type of laser light beam (infrared or green / yellow) which helps to coagulate or seal any bleeding or leaking blood vessels in the retina along with destroying any abnormal vessel growth, reducing swelling etc. As and when diabetic retinopathy progresses, further sessions of laser photocoagulation may be required.

Laser Photocoagulation can be used to
  • Treat macular edema by Modified Grid at the posterior pole
  • It can be used for panretinal coagulation for controlling neovascularization(New fragile abnormal leaking retinal blood vessels) in proliferative retinopathy. A person with proliferative retinopathy will always be at risk for new bleeding, as well as glaucoma, which is a complication arising from growth of the new blood vessels. This means that multiple treatments may be required to protect vision .

Panretinal Photocoagulation reduces the contrast. The night vision is reduced and hampers with driving at night. For patient with Diabetic Maculopathy, the Laser treatment reduces the central vision and may affect the quality of vision. Although, in long term it prevents loss of vision.

Multispot, ultrafast,Precise , micropulse, painless Green or Yellow PASCAL LASER is the latest advancement in this field and it was started for the first time in North India at Grover Eye Laser Hospital.

1. PASCAL LASER : the PATTERN SCAN LASER for Retina & Glaucoma

Multispot, ultrafast, precise, micropulse, painless Green or Yellow PASCAL LASER is the latest advancement in this field and it was started for the first time in North India at Grover Eye Laser Hospital.

PASCAL is a TECHNOLOGICAL BREAKTHROUGH IN PHOTOCOAGULATION LASERS Multi-spot, ultra-fast & safe for Focal or PRP retinal photocoagulation. Delivering a precise pre-set pattern of up-to 56 spots in one shot PASCAL has revolutionized retinal laser treatment. Pascal Laser compensates the patient by being safer, painless, precise and faster and thus the patient tolerates more laser spots in one sitting and hence needs less laser sittings and less repeat visits to the doctor. One or two Pascal sittings are enough for most patients as opposed to 3 to 4 or at times even more sittings needed with older green or red laser.

PASCAL LASER

PAINLESS, PRECISE, PATTERN SCAN LASER – PASCAL – was installed at Grover Eye Laser & E.N.T. Hospital, the first such laser in entire North India.

It is CE & US-FDA approved for the treatment of Proliferative & Non-Proliferative Diabetic Retinopathy. PDR, NPDR.




2. Intravitreal Anti-VEGF

In addition to Pascal laser the use of latest anti-VEGF medication / intra-vitreal injections like Avastin, Macugen or Lucentis / Accentrix at Grover Eye Laser Hospital have made a world of a difference to the treatment of many eye diseases.

Certain new medicines (Anti-VEGF / intra-vitreal injections) like Avastin, Macugen, Accentrix, Lucentis, IVTA & Ozurdex implant etc. are at times used to control leaking blood vessels (neovascularisation) and swelling inside the eye (macular edema). These are given as injections directly inside the eye with all aseptic precautions. People with tendency of brain stroke need special care. All these treatments do not guarantee that diabetic retinopathy can be cured, it can only try to minimize the complications and save at least some useful vision in patients who if left untreated are at a very high risk of going permanently blind.

Intravitreal anti-VEGF drugs eg. Avastin, Lucentis, Accentrix -There are good results from multiple doses of intravitreal injections of anti-VEGF drugs . Present recommended treatment for diabetic macular edema is Modified Grid laser photocoagulation combined with multiple injections of anti-VEGF drugs.

3. Intravitreal triamcinolone acetonide INJECTION / Implant OZURDEX

Triamcinolone is a long acting steroid preparation. When injected in the vitreous cavity, it decreases the macular edema (thickening of the retina at the macula) caused due to diabetic maculopathy, and results in an increase in visual acuity. The effect of triamcinolone is transient, lasting up to three months, which necessitates repeated injections for maintaining the beneficial effect. Complications of intravitreal injection of triamcinolone include cataract, steroid-induced glaucoma and endophthalmitis.

4. Vitrectomy

A vitrectomy is performed when there is a lot of blood in the vitreous. It involves removing the cloudy vitreous and replacing it with a saline solution.

If the bleeding inside the eye is too extensive for direct laser treatment and the same does not clear off on its own within a few months, the blood and fluid inside the eye have to be removed by the major operation of vitrectomy and endolaser. Vitreo-Retinal surgery with endo-laser & silicone oil injection is done in cases of TRD (tractional retinal detachment).

Vitrectomy is frequently combined with other modalities of treatment.

Use of PASCAL Laser treatment and latest anti-VEGF medication / intra-vitreal injections like Avastin, Macugen or Lucentis / Accentrix at Grover Eye Laser Hospital have made a world of a difference to the treatment of diabetic retinopathy.Surgical treatment of diabetic treatment is done by vitreoretinaL surgeon .

Prevention of Diabetic Retinopathy

As explained above, like diabetes itself, once developed diabetic retinopathy can never be totally cured, so prevention plays a very important role. A thorough check-up by an eye specialist at the time of diagnosis of diabetes and regular intervals subsequently aids in timely detection and prompt treatment of complications as and when they occur. All diabetic patients should have regular eye tests (every 6 months / yearly) by a retina specialist even if they do not feel any eye problem of their own. Those who have developed diabetic retinopathy may need more frequent check-ups

Though the duration of diabetes has a strong bearing on the occurrence of this complication (and this unfortunately increases with every year of having diabetes), a strict metabolic control in consultation with the medical specialist / diabetologist is very important.

To minimize further progression of the retinopathy it is very important to control blood sugar (including HbA1c), Lipid Profile (Cholestrol, Triglycerides etc.) & High B.P. Cigarette smoking, tobacco or alcohol abuse and concurrent kidney disease (tested by KFT, urea, creatinine & micro-albumin in urine) increase the severity of the disease and thus should be taken care of.

FAQs

All people with diabetes - both type 1 and type 2 - are at risk. That's why everyone with diabetes should get a comprehensive dilated eye examination at least once a year. The longer someone has diabetes, the more likely he or she will get diabetic retinopathy.

  • Diabetic retinopathy is a major cause of blindness. There are two major types of diabetic retinopathy.
  • One form (proliferative retinopathy) is characterized by the growth of new blood vessels on the surface of the retina, which may lead to hemorrhage and scarring of the retina.
  • A second form, edematous or background retinopathy is characterized by leakage of small blood vessels in the retina, which causes reduced vision.
  • People with diabetic retinopathy may not suffer reduced vision in the early stages, and therefore, regular eye examinations by an ophthalmologist are important, especially for people who have been diabetic for a number of years
  • Assesement of vision on every visit .
  • A detailed dilate fundus examination is a must for every diabetic patient .

To confirm diagnosis, to know the extent of damage ,to plan treatment schedule and to record various changes for future reference we may suggest a fluorescein angiogram and OCT.

Non proliferative diabetic retinopathy is characterized by Intra retinal Hemorrhages with or without swelling of Macula.

Proliferative retinopathy is characterized by the growth of new abnormal blood vessels on the surface of the retina, which may lead to vitreous hemorrhage and retinal detachment.

  • Fluctuating vision
  • Eye floaters and spots
  • Development of a scotoma or shadow in your field of view
  • Blurry and/or distorted vision
  • Corneal abnormalities such as slow healing of wounds due to corneal abrasions
  • Double vision
  • Eye pain
  • Near vision problems unrelated to presbyopia

For a definitive diagnosis, you may need to undergo a test called a fluorescein angiography. In this test, illuminated dye is injected into the body through your veins (IV). As your blood flows, the dye gradually appears in the retina. Your ophthalmologist will photograph the retina and evaluate its appearance.

Diabetic retinopathy is detected during a comprehensive eye exam that includes:

  • Visual acuity test. This eye chart test measures how well you see at various distances.
  • Dilated eye exam. Drops are placed in your eyes to dilate the pupils( Fundoscopy) Retina is examined for early signs of the disease,including damaged nerve tissue
  • Any changes to the blood vessels

To confirm diagnosis, to know the extent of damage ,to plan treatment schedule and to record various changes for future reference we may suggest a fluorescein angiogram and OCT.

  • Retinal changes are the major problem
  • At times diabetes can also cause a rise in
  • eye pressure (glaucoma)
  • clouding of the lens (cataract) at a younger age .
  • weakness of the optic nerve or eye muscle.
  • Damage to the small vessels of the optic nerve can affect vision, and weakness of the eye muscles may cause double vision.

A diabetic is also more likely to develop sudden vision loss due to occlusion of the retinal vessels (branch or central retinal vein occlusion), bleeding in the vitreous cavity, detachment of the retina, or infections of the cornea and vitreous.

  • The indications for treatment depend on extent of severity of the disease
  • The various treatment options include Retinal lasers, Intravitreal VEGF inhibitors and Steroids,
  • The indications for treatment depend on extent of severity of the disease. Laser is the effective treatment for the proliferations in diabetic eyes. If only the central seeing area is affected then usually one sitting of Laser treatment suffices. If there are new blood vessels growing, then the eye is divided into four quadrants and a complete PRP i.e. four sittings of Laser are done spanning over a week to ten days. Initial treatment involves the placement of about 2000 - 3000 burns in scatter pattern, extending from the posterior fundus to cover the peripheral retina in one or more sessions.

The aim of treatment by laser photocoagulation is to convert hypoxic areas to anoxic areas.

The indications for treatment depend on extent of severity of the disease.

  • Laser is the effective treatment for the proliferations in diabetic eyes.
  • If only the central seeing area is affected then usually one sitting of Laser treatment suffices.

If there are new blood vessels growing, then the eye is divided into four quadrants and a complete PRP i.e. four sittings of Laser are done spanning over a week to ten days. Initial treatment involves the placement of about 2000 - 3000 burns in scatter pattern, extending from the posterior fundus to cover the peripheral retina in multiple sessions .

  • Follow-up is done after an interval of 4 weeks after every session .
  • Treatment of recurrence is done by further Laser PRP filling in any gaps between previous laser scars.
  • The most important cause of persistent neovascularization is inadequate treatment. In most eyes, once retinopathy is quiescent, stable vision is maintained.

The aim of treatment by laser photocoagulation is to induce involution of new vessels and prevent recurrent vitreous haemorrhage

LEADING RETINA HOSPITALS OF THE WORLD HAVE SWITCHED OVER TO PASCAL LASER FOR TREATMENT OF THEIR PATIENTS.

Though being costlier than earlier lasers it compensates the patient by being safer, painless ,precise and faster and thus the patient tolerates more laser spots in one sitting and hence needs less laser sittings and less repeat visits to the doctor .One or two Pascal sittings are enough for most patients as opposed to 4 to 6 or at times even more sittings needed with older lasers .

  • Laser treatment can cause an initial blurring of vision for the first 4-6 weeks. The vision usually becomes stable after that.

Major complications like vitreous haemorrahge and Retinal detachment can occur in some patients .Some people develop a condition called macular edema. It occurs when the damaged blood vessels leak fluid and lipids onto the macula, the part of the retina that lets us see detail. The fluid makes the macula swell, which blurs vision.

As explained above, diabetic retinopathy can never be totally cured, so prevention plays a very important role. Though the duration of diabetes has a strong bearing on the occurrence of this complication (and this unfortunately increases with every year of having diabetes), a strict metabolic control in consultation with the medical specialist / diabetologist is very important. Cigarette smoking, abnormal Lipid Profile, High B.P. (hypertension) and concurrent kidney disease (tested by KFT & micro-albumin in urine) increase the severity of the disease and thus should be taken care of.