Silver-Glaucoma

May 22nd, 2019

Archive for May, 2019

Silver-Glaucoma

Wednesday, May 22nd, 2019
What is Glaucoma?

It is a gradual progressive optic neuropathy which is often but not always associated with high intraocular pressure resulting in slow loss of peripheral vision.

It is a leading cause of blindness next only to cataract and is one of the top five disorders targeted by the World Health Organization.

What is the mechanism?

Aqueous humour, a fluid which is secreted by the ciliary body in the eye, normally circulates and egresses out of the eye through a complex meshwork present in the angle recess called the trabecular meshwork (TBM).

The flow of aqueous humour can be restricted at the pupil where the space between lens and iris is very small, at angle recess which is normally a narrow alcove or at the TBM which is like a fine sieve.

This results in build-up of fluid inside the eye and the pressure affects the delicate nerve head of the optic nerve resulting in constriction of the visual field.

What is Intraocular Pressure (IOP)?

Fluid pressure caused by aqueous humour inside the eye is called IOP.

What is normal IOP?

IOP is not a number; it is always expressed as a range. The normal range is between 10 to 20 mmHg

What are the types of Glaucoma?

There are 2 broad classifications of glaucoma

  • Primary
  • Secondary

Primary can be congenital, open angle or narrow angle.

Secondary can be open or narrow angle depending on many identifiable causes.

In the open angle variant the damage is in the TBM while in the angle closure variant the resistance is at the pupil followed by the narrowing of angle recesses.

What are the risk factors?

While IOP is the only modifiable risk factor, family history is also an important risk factor. One out of every five people with glaucoma has a close relative who has it.

What are the causes of secondary Glaucoma?

Trauma to the eye, certain drugs like steroids, medications that have anticholinergic properties like topiramate can precipitate glaucoma.

Certain retinal pathology itself can cause glaucoma like proliferative diabetic retinopathy.

A hyperopic patient with long sight is more prone to angle closure due to the small structure of the eye.

What are the symptoms of Glaucoma?

Most of the time one remains asymptomatic until significant damage is done.

In angle closure glaucoma there can be transient headaches.

In sudden angle closure attack, there may be eye pain, headache, nausea and vomiting. It is often mistaken for a migraine or GI emergency.

What eye tests does one need to undergo?

The tests help in justifying the diagnosis, in making decisions about the management, how effective the treatment has been and whether there has been any progression in the disease.

What are the treatment modalities?

Depending on the type and severity of glaucoma, there are various modalities of treatment from laser and topical medications to surgery. Treatment is tailored depending on the disease’s severity, patient’s age and quality of life.

Is it curable?

Glaucoma, by definition, is a progressive disease no matter what treatment is given. Treatment definitely slows down the progression and stabilises and prevents the visual loss. Hence, early diagnosis, awareness, regular check-ups and prompt treatment is a must to prevent visual loss.

Child-Watery Eyes & Refractive Errors

Tuesday, May 21st, 2019
Watery Eyes in Infants and Children

Watery eyes in a newborn can be due to neonatal conjunctivitis, nasolacrimal duct obstruction (NLDO) or congenital glaucoma. Sometimes watery eyes in a young child can be caused by seasonal allergies.

Tears flow out from the eye through the nose via a tear duct called the nasolacrimal duct which opens into the inferior meatus of the nasal cavity. The opening is partially covered by a mucosal fold called valve of Hasner which usually disappears several weeks after birth.

NLD obstruction is quite common, about 1 in every 20 babies born is present with this condition.

What are the symptoms of a blocked NLD?
  • Waterlogged eyes
  • Mucoid discharge
  • Matting of lashes
  • Sometimes eczema of the skin over the lids due to constant dripping of tears
  • Pressure over the lacrimal sac often produces retrograde reflux of mucopurulent material through the lacrimal puncta

The infection results from stagnation of bacteria in the warm, moist environment of the lacrimal sac. Enlargement and abscess formation may occur in the lacrimal sac in infants with dacryocystoceles.

TREATMENT

The majority of infants with NLDO spontaneously improve during the first several months of life.

Digital massage of the lacrimal sac (Crigler’s massage) is commonly recommended. The goal of the massage is to force fluid through the distal NLD and cause the obstruction to open. If massage is used, it is important to use proper technique, which requires direct digital pressure over the lacrimal sac. The presence of mucopurulent reflux through the puncta indicates that pressure is being applied appropriately. It is not necessary to stroke the finger in a downward motion over the lacrimal sac as commonly taught; compression of the lacrimal sac is the only requirement to proper massage. Many a time parents don’t perform the massage correctly and often get frustrated with its efficacy. A topical antibiotic is recommended if there is significant discharge.

If children do not improve with time and conservative measures fail, surgical treatment is indicated. NLD probing has a fairly high success rate if done within 9 months of birth. In an older child probing is always attempted, if unsuccessful a dacryocystorhinostomy (DCR surgery) should be performed.

General Guidelines for Children with Refractive Errors
  • Play in the garden or an open ground
  • Let sunlight brighten your houses as it protects from myopia; artificial lights have no impact
  • Avoid rubbing as it is associated with increase in astigmatism
  • Wear spectacles all the time
  • Ideal age to use contact lenses for children is > 14 years
  • Ideal age to surgically correct the error is > 18 years
  • Eye exercises, yoga, homeopathy, acupuncture and contact lenses (ortho-k) do not have any effect on myopia progression
  • Get your child an eye check-up by 1 year of age if a sibling or parents use spectacles
While watching monitors
  • Upper limit for the duration of TV watching per day is < 1 hour/day
  • Take a break for 5 minutes after 20 minutes of TV
  • Minimum distance from the TV should be 6 feet and from laptop should be 1 feet
How to choose the RIGHT spectacles for children?

Spectacle Frames:

  • Half rimless or total rimless frames are best avoided in children as the lens falling off or chipping is common
  • Plastic frames are better than metal frames in terms of retaining a good fit for longer
  • Silicon nose rests/pads are useful to reduce pressure imprints on the nose
  • Round or oval eye wire is better than the rectangular ones as it covers the eye
  • Middle level bridge provide better coverage while looking up as well as down than a high or top level bridge
  • A temple with a side-spring is useful as it provides excellent fit for very long

Spectacle Lenses:

  • Avoid glass material as they have low safety profile
  • CR39 plastic is cheaper compared to polycarbonate material. However, polycarbonate is tougher
  • Anti-scratch coating is highly recommended for all plastic lenses
  • Anti-reflective coating and/or high index lenses are necessary for > 4 diopter lenses only
Tackling Refractive Errors in Children

Refractive errors are one of the most important causes of visual impairment in children.

Uncorrected refractive errors can lead to poor vision, quality of life, and scholastic achievement in academics and extracurriculars. It could also lead to inattentiveness and problems like amblyopia or lazy eye and strabismus or crossed eye. A successful correction of a refractive error ensures normal development of binocularity and stereopsis.

One of the most common treatment modalities in children involves the use of spectacles. However, spectacle correction though simple is not straightforward. To achieve a satisfactory correction one should consider an individualised approach.

Important factors that need to be considered while prescribing glasses are the child’s age, type and magnitude of refractive error, amount of anisometropia, and presence of amblyopia or strabismus.

An infant’s world is confined to nearby objects, as a result uncorrected hyperopia is more detrimental than myopia in infants. Very high myopia or can be associated with amblyopia. Kids often get used to these types of vision problem, and might not mention it to their parents. As a result, their amblyopia might not be diagnosed for months or even years, while parents chalk up poor grades or clumsiness to a child not being academically or athletically gifted.

What is Amblyopia?

Commonly known as lazy eye, it is a condition where due to many reasons the eye does not acknowledge the images seen.

What causes Amblyopia?

During the critical period of growth (birth to 6 years old), both eyes must receive clear vision. Anything that interferes with clear vision, like an uncorrected refractive error, will result in amblyopia or anisometropic amblyopia. This is a neurologically active process and results in suppression of the image with a permanent decrease in vision that later cannot be corrected by glasses or any form of treatment.

Early detection and treatment by using glasses, drops and patching offers some of the best outcomes.

If the amblyopia is because of a squint, muscle surgery to improve the alignment of the eyes may be an option.

Patching: eye patches are not just for pirates
  • A child needs to wear an eye patch which is a broad band aid taped on the stronger or good eye for a period of 2 to 3 hours while awake for several months to years depending on the condition. Though it is a challenge, children usually adapt well, and the patch simply becomes part of their day.
  • Beyond 8 years, when kids reach visual maturity it becomes rather hard to treat this condition.
  • When correcting farsightedness in children who are less that 6 years, it is advised to under correct the refractive error, the residual refractive error being just above the mean for that age group. This will act as a stimulus for emmetropia except in conditions like amblyopia and esotropia (convergent squint) where it is imperative to give full cycloplegic correction. In school-going children myopia should be fully corrected.
  • Compliance to the proper spectacle use is as important as a good prescription. This can be improved by the use of frames that fit properly and use of restraints such as a head band in younger children. The spectacle should cover the eyes completely to avoid peeking over the glass.
Did you know?
  • All infants are hyperopic, i.e. have farsightedness, average cycloplegic refractive error being +2.0 D. As they grow a process of emmetropization or becoming normal occurs between 12 months to 6 years
  • It is estimated that 3% of children under 6 have lazy eye
  • An eye patch blocks vision in the child’s good eye forcing the brain to recognise the images seen by the weaker eye

Adult-Diabetic Retinopathy

Tuesday, May 21st, 2019
Diabetic Retinopathy–an Emerging Epidemic

India is deemed the world’s capital of diabetes.

The diabetic population in the country is close to hitting the alarming mark of 69.9 million by 2025 and 80 million by 2030.

A diabetic patient is 25 times more vulnerable to the possibility of becoming blind compared to a healthy individual.

Diabetic retinopathy is often symptomless in the early stages, so screening for diabetic retinopathy in all diabetics is of utmost importance.

What causes Diabetic Retinopathy?

Chronically high blood sugar from diabetes is associated with damage to the tiny blood vessels in the retina, leading to diabetic retinopathy. The retina detects light and converts it to signals sent through the optic nerve to the brain. Diabetic retinopathy can cause blood vessels in the retina to leak fluid or haemorrhage (bleed), distorting vision. In its most advanced stage, new abnormal blood vessels proliferate (increase in number) on the surface of the retina, which can lead to scarring and cell loss in the retina.

Diabetic Retinopathy may progress through Four Stages

Mild non-proliferative retinopathy: Small areas of balloon-like swelling in the retina’s tiny blood vessels, called microaneurysms, occur at this early stage of the disease. These microaneurysms may leak fluid into the retina. Moderate non-proliferative retinopathy: As the disease progresses, blood vessels that nourish the retina may swell and distort. They may also lose their ability to transport blood. Both conditions cause characteristic changes to the appearance of the retina and may contribute to diabetic macular oedema (DME). Severe non-proliferative retinopathy: Many more blood vessels are blocked, depriving blood supply to areas of the retina. These areas secrete growth factors that signal the retina to grow new blood vessels. Proliferative diabetic retinopathy (PDR): At this advanced stage, growth factors secreted by the retina trigger the proliferation of new blood vessels, which grow along the inside surface of the retina and into the vitreous gel, the fluid that fills the eye. The new blood vessels are fragile, which makes them more likely to leak and bleed. Accompanying scar tissue can contract and cause retinal detachment—the pulling away of the retina from underlying tissue, like wallpaper peeling away from a wall. Retinal detachment can lead to permanent vision loss.

Combating Diabetic Retinopathy

Most general ophthalmologists across India lack the necessary equipment to detect diabetic retinopathy in its crucial early stages, when the disease is most sensitive to treatment.

As diabetic retinopathy is often symptomless in the early stages, lots of cases remain undetected. This is also because there are only few tertiary level care centres that have diagnostic tools such as a slit lamp, ultrasound and procedures such as fluorescein angiography.

What is DME?

DME is the build-up of fluid (oedema) in a region of the retina called the macula. The macula is important for the sharp, straight-ahead vision that is used for reading, recognising faces, and driving. DME is the most common cause of vision loss among people with diabetic retinopathy. About half of all people with diabetic retinopathy will develop DME. Although it is more likely to occur as diabetic retinopathy worsens, DME can happen at any stage of the disease.

Who is at risk for Diabetic Retinopathy?

People with all types of diabetes (type 1, type 2, and gestational) are at risk for diabetic retinopathy. Risk increases the longer a person has diabetes. Between 40 and 45 per cent of Americans diagnosed with diabetes have some stage of diabetic retinopathy, although only about half are aware of it. Women who develop or have diabetes during pregnancy may have rapid onset or worsening of diabetic retinopathy.

What are the symptoms of Diabetic Retinopathy and DME?

Diabetic retinopathy typically presents no symptoms during the early stages.

The condition is often at an advanced stage when symptoms become noticeable. On occasion, the only detectable symptom is a sudden and complete loss of vision.

Signs and symptoms of Diabetic Retinopathy may include:
  • Blurred vision
  • Impairment of colour vision
  • Floaters, or transparent and colourless spots and dark strings that float in the patient’s field of vision
  • Patches or streaks that block the person’s vision
  • Poor night vision
  • Sudden and total loss of vision
  • Diabetic retinopathy usually affects both eyes. It is important to make sure that the risk of vision loss is minimised.
Decoding Diabetic Retinopathy
  • It has the potential to cause severe vision loss and blindness
  • It involves changes to retinal blood vessels that can cause them to bleed or leak fluid, distorting vision
  • It is the most common cause of vision loss among people with diabetes and a leading cause of blindness among working-age adults
  • It can be treated with several therapies, used alone or in combination
  • DME is a consequence of diabetic retinopathy that causes swelling in the area of the retina called the macula
  • Controlling diabetes-by taking medications as prescribed, staying physically active, and maintaining a healthy diet-can prevent or delay vision loss
  • Because diabetic retinopathy often goes unnoticed until vision loss occurs, people with diabetes should get a comprehensive dilated eye exam at least once a year
  • Early detection, timely treatment, and appropriate follow-up care of diabetic eye disease can protect against vision loss
How is DME Treated?

DME can be treated with several therapies that may be used alone or in combination.

Anti-VEGF Injection Therapy

Anti-VEGF drugs are injected into the vitreous gel to block a protein called vascular endothelial growth factor (VEGF), which can stimulate abnormal blood vessels to grow and leak fluid. Blocking VEGF can reverse abnormal blood vessel growth and decrease fluid in the retina. Available anti-VEGF drugs include Avastin (bevacizumab), Lucentis (ranibizumab), and Eylea (aflibercept). Lucentis and Eylea are approved by the US Food and Drug Administration (FDA) for treating DME. Avastin was approved by the FDA to treat cancer, but is commonly used to treat eye conditions, including DME.

Most people require monthly anti-VEGF injections for the first six months of treatment. Thereafter, injections are needed less often; typically three to four during the second six months of treatment, about four during the second year of treatment, two in the third year, one in the fourth year, and none in the fifth year. Dilated eye exams may be needed less often as the disease stabilises.

Focal/Grid Macular Laser Surgery

In focal/grid macular laser surgery, a few to hundreds of small laser burns are made to leaking blood vessels in areas of oedema near the centre of the macula. Laser burns for DME slow the leakage of fluid, reducing swelling in the retina. The procedure is usually completed in one session, but some people may need more than one treatment. Focal/grid laser is sometimes applied before anti-VEGF injections, sometimes on the same day or a few days after an anti-VEGF injection, and sometimes only when DME fails to improve adequately after six months of anti-VEGF therapy.

Corticosteroids

Corticosteroids, either injected or implanted into the eye, may be used alone or in combination with other drugs or laser surgery to treat DME. The Ozurdex (dexamethasone) implant is for short-term use, while the Iluvien (fluocinolone acetonide) implant is longer lasting. Both are biodegradable and release a sustained dose of corticosteroids to suppress DME. Corticosteroid use in the eye increases the risk of cataract and glaucoma. DME patients who use corticosteroids should be monitored for increased pressure in the eye and glaucoma.

Why Kokilaben Hospital

We have a state of the art Ophthalmology Department equipped with the most advanced equipment to treat retinal diseases. We are equipped with a Zeiss Fundus Camera for retinal angiography, 532 Zeiss Green Laser for retinal lasers in OPD and during surgeries, ultrasonography—and most importantly the most advanced Alcon CONSTELLATION® vitrectomy surgery machine which is used for 23 and 25 gauge minimal access retinal surgeries.

Increased VEGF (vascular endothelial growth factor) levels in the vitreous are the major culprits in diabetic retinopathy. Anti-VEGF intravitreal injections have become the most important tool in stabilising and reversing diabetic macular oedema as well as controlling proliferative diabetic retinopathy bleeding.

At our hospital we provide the best Anti-VEGF intravitreal injections like Ranibizumab (Accentrix or Lucentis, Razumab) and Aflibercept (Eylea).