Glaucoma is a progressive disease of the optic nerve that leads to irreversible visual loss. However, clinical studies have confirmed that early detection and treatment of glaucoma can slow the progression of permanent optic nerve damage and blindness.

Now patients have a newer, more advanced option: The Heidelberg Retinal Tomography 3 (HRT 3) has been proven to be superior to all other available optic nerve imaging techniques, and uses the latest in scanning laser technology for early detection and follow-up of glaucoma. This instrument is a laser ophthalmoscope which can precisely measure and analyze the shape of the optic nerve. The HRT 3 is not a treatment laser, and is not harmful to the eye (it operates similar to a CAT scan, minus x-rays).

Data from successive HRT 3 exams are superimposed on the original data (or base line exam) for a point-by point comparison to identify changes over time. Therefore, repeated measurements of the optic nerve using HRT 3 can pick up glaucoma damage many years earlier than visual field testing. These subtle changes will help to determine:

  • When treatment is necessary ( for glaucoma suspects)
  • When treatment should be increased or surgery considered ( for patients with existing glaucoma damage)

The test is safe and takes moments to complete: Patients look at a target light and must not blink or move the eye for several seconds while the image of their optic nerve is being taken. (Dilating drops may be necessary if a patient has cataracts or corneal scarring). The HRT 3 tests are used to monitor the progression of your glaucoma and the frequency of follow-up exams as determined by your doctor, and based on whether the progression of your glaucoma is stable or aggressive.

Payment, which is not covered by OHIP, is due at the time of the exam. A receipt for your health insurance or tax purposes will be issued.


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