Glaucoma

What is glaucoma?

Glaucoma is a group of eye diseases that gradually steals sight without warning and often without symptoms. Vision loss is caused by damage to the optic nerve. This nerve acts like an electric cable with over a million wires and is responsible for carrying the images we see to the brain. High eye pressure is the main cause of optic nerve damage.

What causes glaucoma?

Clear liquid called the aqueous humor flows in and out of the eye. This liquid is not part of the tears on the outer surface of the eye. You can think of the flow of aqueous as a sink with the tap turned on all time.

If the drainpipe gets blocked, water collects in the sink and pressure within the inner eye increases, which can damage the optic nerve.

Once the optic nerve gets damaged, a person loses vision that can never be regained. If the treatment of glaucoma is imperfect, a person can continue to lose vision.

Are there different types of glaucoma?

There are numerous different types of glaucoma: primary open angle glaucoma is the most common glaucoma the world over. The ‘drainpipe’ or drainage angle of the eye becomes less efficient with time, and pressure within the eye gradually increases.

Primary Angle Closure Glaucoma

It is the most common glaucoma type found in India. Here the drainage angle gets blocked and the liquid cannot reach the drainage angles to leave the eye, so the pressure in the eye increases.

Congenital Glaucoma

It is seen in infants & children. The drainpipe may have been incorrectly “birth iheritted ” .It is the most common glaucoma type found in India. Here the drainage angle gets blocked and the liquid cannot reach the drainage angles to leave the eye, so the pressure in the eye increases.. Since the eye of an infant is more elastic, it increases in size and becomes white in color.

There are other conditions like injuries to the eye, some drugs & diseases that can block outflow channels & cause secondary glaucoma. Patients with asthma and allergic skin and eye diseases often use inhalers, skin creams or eye drops containing steroids that can cause glaucoma. Persons who have undergone multiple eye surgeries are also at high risk of this glaucoma. Contact Shalby Hospital for Diabetic Retinopathy, Retinal Detachment, Squint Surgery, in India, call +91-79-40203144.

What is the incidence of glaucoma?

4.5 out of every 100 persons have glaucoma. It is the second leading cause of irreversible blindness the world over. Almost 4 million Americans have glaucoma and about half do not even know they have the disease.

Who is at the risk for glaucoma?

  • Person with a family history of glaucoma
  • Person with thick glasses
  • Diabetics
  • Person who has used steroid medications
  • Previous eye injury or surgery
  • Age more than 35 years

How does a person know he has glaucoma?

Glaucoma can steal vision so quietly that the patient can be unaware of the trouble until the optic nerve is badly damaged. Because no symptoms occur, the best way to diagnose this disease is by periodic medical eye examinations. Some patients do have blurred vision, severe pain, can see rainbow haloes around lights or have nausea and vomiting with headaches.

How is glaucoma detected?

Early detection through regular and complete eye exams is the key to protecting your vision from damage caused by glaucoma. Visual acuity is affected late in the course of this disease. Good vision does not mean absence of this disease in the eye.

There are some procedures required to detect glaucoma:

1. Applanation tonometry

This is a procedure that measures the pressure of the eye.

2. Gonioscopy

This is an examination of the drainage areas of the eye to diagnose the type of glaucoma. This test is very important as the treatment of different types of glaucoma is different.

3. Disc examination

This test is carried out to evaluate damage to the optic nerve of the eye. To carry out this test, eye drops are placed in the patient’s eyes to dilate the pupil.

4. Automated visual field examination

Small changes in the patient’s eye sight that a patient may not notice can be detected by this machine. Sometimes the appearance of optic nerve head can be misleading. In such cases, a correct decision can be taken after field examination. This test is repeated in all patients of glaucoma & optic nerve diseases at regular intervals to determine whether the patient is gradually losing eyesight.

5. Pachymetry

This procedure measures the thickness of the cornea. Corneal thickness can mask an accurate reading of eye pressure. Patients with thin corneas show artificially low pressures that are dangerous, as glaucoma may not get detected. Patients with thick corneas may show artificially high readings. Such patients may sometimes be unnecessarily treated in the absence of the disease.

6. Optic nerve computer imaging

In the recent years, there have been new techniques developed for optic nerve imaging. The HRT scans the retinal surface and optic nerve with a laser light. It then constructs a 3-dimensional image of the optic nerve. This computerized test helps to detect glaucoma early before other methods & most importantly, also helps to detect if there has been further loss of vision after the treatment started. This test is normally recommended every year.

7. Ultrasound Bio-microscopy

It is a sophisticated modern imaging machine that examines deeper structures in the front part of the eye. These areas cannot be visualized with other examinations like Gonioscopy.

How is glaucoma treated?

In most situations, glaucoma cannot be cured. Treatment is given to preserve the existing vision. This means that vision cannot be improved.

A complete glaucoma examination is necessary before any treatment plan is made. In eyes with narrow angle glaucoma, lasers are done first to preserve the angle opening. In persons with open angle glaucoma, eye drops are given to lower eye pressure. In persons in whom glaucoma cannot be well controlled with these simple measures, there are several different operations and laser treatments available.

Facilities

High End Equipment in the new Glaucoma Department include:

  • Humphreys perimeter
  • Perimetry using latest GPA software for analysis of field progression
  • Sonomed Ultrasound Biomicroscopy for imaging the anterior segment not seen by Gonioscopy
  • For imaging the anterior segment not seen by Gonioscopy
    HRTIII
  • Sophisticated technology for imaging and analyzing progression in the optic nerve head
  • Gonioscopy lenses
  • Angle visualization using special 6 mirror and 4 mirror lenses
  • Diagnostic lenses
  • Binocular assessment of the optic nerve head using third generation digital lenses
  • Ultrasonic Pachymetry for measurement of corneal thickness
  • For measurement of corneal thickness
  • Perkins tonometer for examination of children in OT under anesthesi
  • For examination of children in OT under anesthesia
  • Microscope
  • Carl Zeiss operating microscope
  • Operating Room
  • An operation theatre of international standards

Along with these diagnostic facilities, we have dedicated high end operating rooms for Glaucoma cases needing surgery. Also as Shalby Hospital is a multispecialty hospital well equipped to manage most co-morbid conditions in Glaucoma patients, the department is capable of treating morbid and compromised Glaucoma patients.

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