What test is used to confirm diagnoses involving the cornea?

The fluorescein stain test is specifically designed to evaluate the health of the cornea. This test involves the application of a fluorescent dye to the surface of the eye. When light from a blue light source is shone on the eye, any damage or irregularities in the cornea will appear bright green due to the absorption of the dye. This makes it an effective tool for diagnosing various conditions affecting the cornea, including corneal abrasions, ulcers, and infections.

In contrast, other tests like blood tests are more suitable for detecting systemic issues or infections, whereas X-rays primarily focus on skeletal structures and are not relevant to soft tissue or corneal assessment. A CT scan, while capable of providing detailed images of the structures of the eye, is generally used for more complex conditions and would not be the first line of investigation for corneal issues. Therefore, fluorescein staining is the most appropriate and effective method for confirming diagnoses related to the cornea.