Breakthrough Treatment for Glaucoma

Glaucoma is a condition in the eye caused by excessive fluid pressure. This raised pressure damages the optic nerve that enables vision and consequently causes blindness. Treatments aim to relieve the pressure by decreasing the volume of aqueous humor, which is the fluid in the eye. Certain drugs reduce the production or increase the outflow of this fluid. In 1989 the first laser eye surgery was performed. Since then laser eye surgery has been refined to become a widespread treatment for glaucoma.

Open-Angle Glaucoma

• There are two types of glaucoma. Primary open-angle glaucoma is the most common form. An outflow of fluid from the eye causes this form of glaucoma. This is more prevalent among elderly people and African Americans who have five times the risk than others. Primary open-angle glaucoma is painless; loss of sight does not occur until the condition is advanced.

Closed-Angle Glaucoma

• The second type of glaucoma is acute closed-angle glaucoma and is considered an emergency. The pressure in the eye rises to a harmful level suddenly caused by the lens pushing the iris forward and blocking the drainage of fluid. Patients experience a red painful eye and have blurred vision. They may vomit, become nauseated or complain of a headache.

Drug Treatments

• Damage to the eye caused by glaucoma is irreparable; however, further damage treatment may prevent further damage. The first line of treatment against glaucoma is to prescribe eye drops. One type of eye drops is alpha adrenergic agonists that reduce the production of fluid and increase its drainage thus reducing the pressure. However, these drugs can cause side effects including increased heart rate, heightened blood pressure, headaches, fatigue, blurry vision and dry mouth.

  Beta blocker eye drops also reduce the production of fluid but these can cause side effects such as slow heart rate, depression, drowsiness and breathing difficulties. Therefore, patients with heart disease or asthma should not take beta blocker eye drops. Other drugs, such as miotic drugs, increase the outflow of fluid, and carbonic anhydrase inhibitors reduce the synthesis of fluid. If eye drops do not improve the glaucoma, a doctor will consider a surgical treatment.

Laser Treatments

• A trabeculoplasty is the most common surgical treatment for glaucoma. Fluid drains out the eye through channels called canals of Schlemm. High energy laser beams unblock the canals of Schlemm and allow the passage of fluid. This surgery often treats open-angle glaucoma. Patients with more severe closed-angle glaucoma may need laser peripheral iridotomy. The laser beams create a small hole in the iris of the eye to facilitate drainage.

  A doctor will often combine laser eye surgery with prescription eye drops for maximum effect; however, the success of laser eye surgery varies from person to person. It is possible for the effects of laser eye surgery to wear off over time. If both eye drops and laser eye surgery are ineffective at treating glaucoma, a doctor may suggest conventional surgery as an alternative.

Conventional Surgical Treatments

• A canaloplasty makes a tiny incision into the eye and enlarges the canals of Schlemm. This is a temporary solution and aids the passage of fluid from the eye. An international study published in May 2009 by the Journal of Cataract and Refractive Surgery reported that the canaloplasty is safe and effective at reducing pressure in the eyes of patients with open-angle glaucoma.

  A trabeculectomy removes a portion from the wall of the eye creating a flap, which is sutured by the surgeon. The gap created allows fluid to drain through thus reducing the pressure in the eye. This surgery gives patients an increased risk of developing cataracts.

  If these surgeries fail, the doctor will consider a further procedure in which a surgeon inserts a drainage tube into the chamber near the front of the eye and a plate beneath the conjunctiva of the eye. The fluid flows into the tube and out of the chamber. This is called a glaucoma drainage implant.