Campimetry or visual field is an ophthalmological test that measures the total field of vision around a fixed point. It determines the amplitude of your peripheral or lateral vision once you have focused on an object.
It is also used to specifically or frequently measure the evolution of the visual field.
How is campimetry performed?
The test is performed in a room with very low light or in darkness. It is easy, but requires great cooperation from the patient who must concentrate.
It is normally performed using a campimeter, which is an appliance that emits small lights that move at different intensities (static or computerised campimeter).
The patient sits down and rests their head on a machine that projects small lights or flashes. The aim is for the patient to recognise the peripheral lights without looking away from the central point. The patient should press a button whenever each light is seen.
As the test progresses, the campimeter draws a vision map that shows the areas that the patient is able to see that those he/she is unable to see.
6 key aspects
- It is a painless test for patients.
- It is a non-invasive test (no risks or counterindications).
- It requires no prior pupil dilation.
- It requires no prior preparation.
- Test time: around 10-15 minutes per eye.
- It might sometimes take longer due to the patient’s visual deficit.
What diseases can be diagnosed?
- Patients with glaucoma to track their evolution (evolution of the visual field).
- Patients with retinal diseases (scotoma, retinitis pigmentosa).
There are also systematic diseases that are seen as defects and variations in the visual field (optic neuritis, brain diseases, diabetes, etc.).