Visual Field Testing in Ranchi
Comprehensive perimetry (visual field testing) for glaucoma, neurological vision disorders, and optic nerve conditions — performed and interpreted by Dr. Dibya Prabha at Neurovision Clinic.
What is Visual Field Testing (Perimetry)?
Visual field testing, also called perimetry, is a systematic method of measuring the entire scope of a person's vision — both central detail vision and peripheral (side) awareness. The test maps the sensitivity of vision across the visual field, detecting areas of reduced or lost vision (scotomas) that the patient may not be consciously aware of. At Neurovision Clinic, Dr. Dibya Prabha uses automated perimetry to diagnose and monitor glaucoma (where peripheral vision loss is often the first sign), assess optic nerve damage from neurological conditions, evaluate vision loss after stroke affecting visual pathways, and monitor for medication toxicity affecting the retina or optic nerve.
Why is Visual Field Testing (Perimetry) Done?
- •Diagnose and monitor glaucoma — detect peripheral vision loss before the patient notices it
- •Evaluate optic nerve disorders including optic neuritis, ischemic optic neuropathy, and papilledema
- •Assess vision loss after stroke or brain injury affecting visual pathways in the brain
- •Monitor for hydroxychloroquine (Plaquenil) retinal toxicity in rheumatology patients
- •Evaluate unexplained vision loss — differentiate retinal from neurological causes
- •Document visual function for disability assessment or medico-legal purposes
- •Monitor pituitary tumors and other brain lesions compressing the visual pathways
How Visual Field Testing (Perimetry) is Performed
Setup
You sit comfortably at the perimeter machine. One eye is patched. Your chin and forehead are positioned against supports. The room lighting is standardized.
Instructions
The technician explains: keep looking at the central orange fixation light at all times. Small white lights will flash at various locations and brightness levels. Press the button each time you see a light — even if it's very dim. It's normal to miss some lights.
Testing
The automated program presents lights at various locations in your visual field. You respond to each light you see. The machine adjusts light intensity to determine the threshold of visibility at each point. A typical test takes 5–10 minutes per eye.
Analysis
The machine generates detailed maps and statistical analyses. Dr. Dibya Prabha reviews the results, compares them to any previous tests, and integrates the findings with your complete eye examination and OCT results.
How to Prepare
- •No special preparation is needed — you can eat, drink, and take medications normally
- •Bring your current glasses — you'll wear them during the test if needed (near correction for the central target)
- •Get a good night's sleep — fatigue affects concentration and test reliability
- •The test requires concentration — if you're not feeling well, consider rescheduling
- •A practice test may be run first to familiarize you with the process
Related Conditions
Visual Field Testing (Perimetry) helps diagnose and monitor these conditions. Explore our condition pages for more detailed information about each.