Glaucoma is a complex disease that causes gradual diminution of the peripheral vision over many years. Advanced cases may ultimately affect the central vision, resulting in blindness.
The key to management of glaucoma is early diagnosis and treatment. The eye pressure, optic nerve appearance, and thickness of the optic nerve fiber play important roles in the progression of glaucoma.
We employ the latest technologies in the diagnosis and treatment of glaucoma:
Visual Field Testing for Glaucoma – The Humphrey Zeiss 700 series visual field testing is one of the fastest and most accurate methods for mapping the peripheral and central visual fields to detect early changes consistent with glaucoma.
Tonometry (Tonopen Pressure Measurement) – Intraocular pressure measurements are performed by experienced personnel using Goldmann applanation tonometry or Tonopen tonometers. We do not use “air puff” methods, as they are more uncomfortable for patients, and are not as accurate as the above methods.
Measure Corneal Thickness – Corneal thickness (Pachymetry) measurements will determine the accuracy of the intraocular pressure measurements in correlation to each individual cornea. Ultrasound pachymetry is a painless, and accurate method of determining the corneal thickness. Pachymetry can also be determined in an optical method (no touch) using the Stratus OCT (Optical Coherence Tomography).
Document the Optic Nerves – Fundus photography using the Carl Zeiss Visucam will document the appearance of the optic nerves for serial comparisons over periods of time. This will help to determine stabilization or progression of the disease and response to therapy.
Optic nerve fiber analysis by Cirrus OCT (Optical Coherence Tomography) provides a higher level of diagnostic insights. Using near-infrared frequency light, it reveals cross-sectional views of the optic nerves and its fibers with high resolution. Computerized comparisons are graphed and compared to age-matched normative data.
There are different types of glaucoma:
- Primary open angle glaucoma: This is the most common type of glaucoma in the United States. The cause is presumed to be a microscopic obstruction of the drainage system of the fluids circulating in the anterior compartment of the eye. The intraocular pressure is usually high, with abnormal optic nerve appearance and peripheral visual field defects consistent with glaucoma.
- Narrow angle glaucoma: This is more common in patients of Asian origin or in high degrees of hyperopia (far-sightedness), where the anterior compartment of the eye is crowded with structures causing mechanical obstruction of the drainage site of fluids circulating in the eye.
- Glaucoma suspects: This is a term given to patients who have a suspicious optic nerve appearance, yet all other parameters and testing are normal. Glaucoma suspects are statistically at a higher risk than normal individuals for developing primary open angle glaucoma. Stratus OCT testing helps in determining high risk glaucoma suspects, and prophylactic treatment may be instituted in these cases.
- Ocular hypertension: This is a term given to patients with elevated eye pressure, yet all other parameters and testing are normal. Corneal pachymetry and Stratus OCT testing help in determining high risk ocular hypertension patients, and prophylactic treatment may be instituted in these cases.
Treatment of glaucoma:
- Selective laser trabeculoplasty (SLT): Is the latest, state-of-the art technology to control glaucoma, and is available to San Antonio Eye Specialists patients. A less than 5 minute, relatively painless and simple in-office procedure that utilizes a laser beam to improve the outflow (drainage) and hence control glaucoma. It is safely repeatable, and is effective in 60-95 % of patients according to the type and severity of glaucoma.
- Medications: Many patients are controlled with medical therapy using topical drops. There are many classes of drops; some reduce the production of aqueous (fluid) in the eye, and others try to improve the drainage. Some glaucoma drop regimens can control glaucoma with once daily dosing at bed time. Others may require twice or three time daily dosing.
- Glaucoma filtration surgery: This is considered a last resort, if glaucoma cannot be controlled by medications or laser. There are different types of glaucoma surgical procedures. The most commonly performed, trabeculoplasty, creates a channel that drains the fluid from inside the eye to the outside under the conjunctiva (the skin of the the eye). A medication called Mitomycin-C is commonly used during this procedure to prevent postoperative scarring and closure of this channel. More involved procedures include using “Seton devices”, or synthetic tubes that drain the fluid from inside the eye to to the outside. This is reserved for advanced types of glaucoma.
Ziemer Galilei G4
We are excited to have one of the most accurate diagnostic tools in the industry, the Ziemer Galilei G4. This device is critical in refractive or laser vision correction surgery. It allows our doctors to obtain precise corneal thickness, corneal curvature and also screens for keratoconus. This device also evaluates the corneal surface to check for any abnormalities, and measures higher order aberrations.
Zeiss Fundus Photography (VisucamLite)
San Antonio Eye Specialists is proud to offer our patients the next level in non-mydriatic color fundus photography. Non-mydriatic means a photo of your retina can be taken without dilation through pupils as small as 3.3 mm. The high-quality system produces images to help in diagnosing eye diseases such as diabetic retinopathy, glaucoma and Age-Related Macular Degeneration (AMD).
Heidelberg Retina Tomograph
We are excited to offer our patients this technology for diagnosing early stages of glaucoma as well as to measure the progress of the disease. The Heidelberg is pivotal to our Glaucoma Study.