Special Tests for Corneal Diseases

Special Tests for Corneal Diseases

The cornea is a vital part of the eye, which may at times get damaged through various conditions, diseases, and infections. To ascertain corneal diseases in India, the ophthalmologist may have to conduct any of the following corneal tests;

• Schirmer’s Test
  The Schirmer’s Test is the measure of the tear secreting capacity of the eye. You must note that a deficiency in tear secretion may lead to a chronic eye condition known as “dry eye”. During this test, a special filter paper strip is placed across the lower eyelid margin and also the measurement of the length of the strip wetted by the tears over a period of one minute is conducted
• Corneal Topography
  This is the detailed mapping of the surface of the cornea. Advanced computer analysis of several spots on the corneal surface is performed using the study of the reflected image.

The color-coded graphs of the surface map enable the doctor to diagnose certain conditions like Keratoconus. This procedure is crucial before an excimer laser treatment

• Keratometry
  This test involves the measurement of the corneal curvature in two meridians. In the real sense, the cornea is the front and clear part of the eye with a curvature. The curvature of the cornea helps it to focus partly. The measurement of the corneal curvature is required for fitting the right contact lens and calculation of the IOL power before a cataract surgery
• Pachymetry
  Pachymetry is the study of the cornea’s thickness. The accurate measurement of the thickness occurs with the help of an ultrasound or optical means. This test is vital in the diagnosis and measurement of some corneal conditions such as; corneal endothelial dystrophy and keratoconus.
• Specular Microscopy
  Specular Microscopy is a test used to evaluate the back most layer of the cornea known as the endothelium. The endothelium’s health is important in maintaining clarity of the cornea.

This layer is in most cases affected by eye diseases, injury, age advancement, or surgery that reduces the cells in the layer rendering it become abnormal. In this test, the ophthalmologist will evaluate the present number of cells per square millimeter and as well study the types of cells before a surgery is conducted