Laser Procedure for Glaucoma

 

Glaucoma is a disease in which the optic nerve is damaged by factors such as increased intraocular pressure (the pressure of the eye). Since the optic nerve is responsible for transmitting visual  messages to the brain, damage to it (gradually) causes visual field defects, and if the condition is not diagnosed or treated, the increased intraocular can damage the optic nerve and eventually lead to blindness. This surgical procedure is performed at Tehran-Iran Noor Eye Hospital.

 

In some cases, the cause of glaucoma is detectable, such as eye injury, eye surgery, and angle closure, but in many cases glaucoma has an unknown cause and many genetic and environmental factors are involved.

Types of Glaucoma

 Glaucoma can be divided into two groups, open-angle glaucoma and angle-closure glaucoma. It is good that you also know that the angle of the eye is part of the eye that is between the iris (the color part of the eye) and the cornea (the transparent part of the eye). Typically, the front part of the eye is filled with a clear fluid which is produced in the eye and exits the eye via the drainage angle of the eye. If the drainage angle of the eye is damaged or closed, this fluid is not able to exit the eye and it causes to increase intraocular pressure and the occurrence of glaucoma.

In most cases, the patients suffer from open-angle glaucoma, but a significant percentage of the patients also suffer from narrow-angle or closed- angle glaucoma.

Glaucoma symptoms

 The symptoms of glaucoma vary depending on its type:

A. Congenital glaucoma with symptoms such as cloudiness of the cornea, tearing, photophobia( light sensitivity) and enlarged eyes.

B: Open- angle glaucoma: In most cases, open-angle glaucoma (as well as angle- closure glaucoma), the patient does not notice glaucoma unless the disease progresses and causes visual field defects.

 C: Acute angle- closure glaucoma: This disease has acute symptoms such as vision loss, tearing, photophobia( light sensitivity), seeing rainbow-like halos around the lights, nausea and vomiting. In such a situation, the patient should be referred to an ophthalmologist and be treated immediately as an urgent case. Ocular Emergency department of Tehran-Iran Noor Eye Hospital provides appropriate around- the- clock services for all emergency eye patients.

 

In most cases, full-scale clinical examinations, including intraocular pressure measurements,  Gonioscopy ( an examination to look at the angle of the eye), determination the status of the optic nerve and visual field test are enough to detect glaucoma; however, in some cases, other tests, such as optical coherence tomography (imaging of the optic nerve and the retina) is also required. All of these ophthalmological services are carried out at Tehran-Iran Noor Eye Hospital.

 Glaucoma Treatment

In the process of glaucoma, the optic nerve is gradually damaged and its nerve cells die gradually. Unfortunately today there is no cure for the part of the optic nerve fibers that is lost and when glaucoma is diagnosed, the main goal of its treatment is to prevent the progression of the disease and preserve the remaining vision for the normal life of the patient.

Glaucoma is treated step by step. The treatment process is started by drug therapy (pharmacotherapy) and if it is not successful, the pressure of the eye is reduced by laser treatment. And in the acute cases, when the Laser is not successful, conventional surgery is performed.

Medical Therapy of Glaucoma

The most common type of early treatment for glaucoma is drug therapy. Glaucoma medications are prescribed as eye drops and pills. These medications reduce the intraocular pressure in two ways. Some of these medications decrease the production of fluid in the eye, and some of them help the eye's fluid to drain better from the eye.

 

Laser Treatment for Decreasing Intraocular Pressure

 - Laser Iridotomy:

A surgical procedure that is performed on an outpatient basis. In this method, a tiny opening is created in the iris, which allows the intraocular fluid (aqueous humor) to drain more easily in the eye's angle. This method is applicable to patients with narrow-angle or closed- angle glaucoma.

- Selective laser trabeculoplasty:

This method is used to treat open-angle glaucoma. In this method, a wavelength is used that only affects the cells that contain melanin in the trabecular meshwork. The initial biological response to this wavelength is in the order that releases Cytokines ( a type of chemical intermediates), and they also activate and accumulate Macrophages (a type of white blood cell, ) and make changes that ultimately lead to lower intraocular pressure.

Since the wavelength used in this technique does not cause injury to other ocular tissues, it can be repeated several times throughout life.

- Endoscopic cyclophotocoagulation:

In this method , is used in the operation room of Tehran-Iran Noor Eye Hospital, the ciliary body of the eye that causes the ulcerative fluid to secrete is treated. This process reduces the secretion of alkaline fluid and ultimately reduces eye pressure. This is a surgical procedure that usually is applied simultaneously with cataract surgery. The ophthalmologists of Tehran-Iran Noor Eye Hospital provide you with additional information about this treatment.

 

1. Take a shower the night before your surgery and wash your face with soap or diluted baby shampoo.

 2. According to the time of surgery given to the patient by the surgical team, consider your nutritional care and have healthy and balanced diet.

3. If you are taking a certain medicine, be sure to tell the surgeon, ophthalmologist and anesthesiologist.

 Attention:

 * Antihypertensive and lipid lowering drugs should be taken according to your previous order.

 * Heart medications should be taken according to the previous order. If you take aspirin and warfarin, do not take these medications before surgery, if possible, but before taking any action be sure to consult your ophthalmologist.

* Tell your ophthalmologist if you have diabetes.

*Get ready for preoperative tests including blood tests and cardiovascular advice.

 

1. After discharging from the hospital, a plastic shield and an eye dressing will be placed on your eye. Avoid taking off your eye dressing at home.

2. It is better to rest on the first day after surgery. After glaucoma surgery, avoid lifting heavy objects (typically greater than 2 kg). If you have to go up the stairs, you should do it with your family or close relatives help.

3. When you rest and sleep, your pillow should be higher than usual.

 4. Eating light foods, eating healthy vegetables and fruits is good for quick recovery.

 5. After glaucoma surgery, there is a feeling of a foreign body in the eye. Moderate sedation is prescribed to reduce the discomfort.

* Important Note:

- One day after surgery, the patient should be referred to Tehran-Iran Noor Eye Hospital for follow-up visit and examination.

 - Glaucoma surgery is done to preserve remaining vision and prevent blindness, and does not improve the visual acuity and sight already lost.

 - At what age can glaucoma develop?

- What causes glaucoma?

- How can I know that I have glaucoma?

- What are the clinical examinations for glaucoma?

- When can I undergo Laser surgery for decreasing intraocular pressure?

- Which patients are the best candidates for Laser lridotomy ?

- When is Selective Laser Trabeculoplasty the best choice for glaucoma treatment?

 

 

 

 - At what age can glaucoma develop?

 Normally people over the age of 40 are at risk for developing glaucoma and they need to get regular eye examinations.

- What causes glaucoma?

The main cause of glaucoma is inheritance and genetic factors, but according to physicians, taking some migraine medications and the long-term use of oral, inhaled, and intravenous corticosteroids and especially eye drops, which are commonly prescribed for the treatment of allergies and eye sensitivity, can lead to glaucoma in people who are at high risk for this disease. Cardiovascular disease, diabetes, sedative medications and antihistamines are also effective in developing glaucoma.

- How can I know that I have glaucoma?

 *Congenital glaucoma has symptoms such as cloudiness of the cornea, tearing, photophobia (light sensitivity) and enlarged eyes.

 * Open- angle glaucoma usually has no symptoms unless the disease progresses and causes visual field defects.

* Acute angle- closure glaucoma has acute symptoms such as vision loss, tearing, photophobia ( light sensitivity), seeing rainbow-like halos around the lights, nausea and vomiting. In such a situation, the patient should be referred to an ophthalmologist and be treated immediately.

- What are the clinical examinations for glaucoma?

Intraocular pressure measurements, Gonioscopy ( an examination to look at the angle of the eye) and determination the status of the optic nerve and visual field. If needed, an ophthalmologist will prescribe testoptical coherence tomography (imaging of the optic nerve and the retina) that can be obtained at Tehran-Iran Noor Eye Hospital.

- When can I undergo Laser surgery for decreasing intraocular pressure?

Laser surgery helps to drain fluid from the inside of the eye. Although this method can be used at any time, it is usually used after drug therapy. In many cases, the patient should take medication after laser surgery.

- Which patients are the best candidates for Laser lridotomy?

This method is applicable to patients with narrow-angle or closed- angle glaucoma. The surgical procedure that is performed on an outpatient basis. In this method, a tiny opening is created in the iris, which allows the intraocular fluid (aqueous humor) to drain more easily in the eye's angle.  

- When is Selective Laser Trabeculoplasty the best choice for glaucoma treatment?

This method is used to treat open-angle glaucoma. Since the wavelength used in this technique does not cause injury to other tissues, it can be repeated several times throughout life.