Definition
An open angle glaucoma (OAG) patient is no longer a suspect, but has been diagnosed with an incurable disease that has damaged their optic nerve. The open angle description means that the angle of the eye is open and that the angle is not contributing to the status of the disease. Again, much like other chronic disease like high blood pressure or diabetes OAG is incurable and requires chronic management.
Work-up
The work-up for a patient with open angle glaucoma requires interval testing that allows the doctor to monitor for progression of disease. Usually the patient is seen three to four times a year for pressure evaluation and interval tests that allow the doctors at Newsom Eye to appropriately intervene with treatment if the patient is not doing as planned.
Testing
The amount of glaucoma testing varies to some extent with the severity of the disease, but usually is performed on an annual basis. Each test gives us a different piece of information on how the patient is doing.
Gonioscopy will be needed typically on the first visit or soon thereafter to look at the place in the eye where fluid drains out of the eye. Many glaucoma patient’s do not have normal anatomy here and this will give the doctor a key to treatment.
Optic nerve photography is also very important as it gives the doctor photographic evidence of what the patient’s optic nerve looked like at that moment in time. Much like following skin lesions for suspicion of cancer, photographs are critically important for looking for change over time.
HRT or Optical Coherence Tomorography (OCT) are the modern technologies that Newsom Eye uses to laser scan the nerve fiber layer of the optic nerve. This not only analyzes against a database for disease, but also stores the findings for future reference with the patient to detect even the slightest progression of the disease.
Pachymetry is used to measure the central corneal thickness which we now know is an important data point to reference for glaucoma risk. This test is usually only performed once unless surgery or trauma changes the structure of the cornea.
Treatment
Open angle glaucoma is treated in one of three ways; medically, with laser or with surgery. Typically, less risky options such as SLT and medication are used before the jump to filtration, shunts or valves. It is the doctor’s duty to choose the course of action and follow through with it to stabilize the patient. Endocyclophotocoagulation or ECP is a laser procedure usually performed simultaneously with cataract surgery. Click here to learn more about ECP.
Gonioscopy: This is an important test where a mirrored, handheld device is used by the doctor to look at the drainage channel in the patient’s eye.
Visual Field: This is required to analyze and document the peripheral vision of the patient. Peripheral vision is what glaucoma damages over time.
Photos of the Optic Nerve: Glaucoma damages the optic nerve, therefore pictures are taken to watch for changes in this important tissue.
Optical Coherence Tomography (OCT):Perhaps the most important and technologically advanced instrument available for glaucoma, this instrument provides an optical analysis of the nerve with stunning accuracy.
Serial Tonometry: Intraocular pressure, or the pressure in the eye, varies throughout the day and is a critical measurement in glaucoma. Multiple pressure measurements are necessary to record the variation and help understand this condition.
Pachymetry:This is a newer test that standardizes the pressure reading for patients by measuring the thickness of their cornea.
