Corneal endothelial cell count

The cornea is the transparent front window of the eye, responsible for focusing light rays onto the retina. The innermost layer of the cornea consists of endothelial cells. These cells are crucial for maintaining corneal clarity by actively pumping excess fluid out of the cornea. When endothelial cells function properly, the cornea remains clear, allowing for sharp vision.

An endothelial cell count, also known as specular microscopy, is performed to assess the health of the endothelial layer. It measures the density of the cells (number per unit area), their size (polymegathism), and their shape (pleomorphism). These findings help the doctor understand the corneal condition, identify signs of damage or disease, and plan future treatments or surgeries, especially those that might affect the cornea.

The test is recommended in various situations. It is used to monitor degenerative corneal diseases, such as Fuchs' endothelial dystrophy, or intraocular inflammatory conditions that may harm endothelial cells. Additionally, it is essential before certain eye surgeries, such as cataract surgery or corneal transplantation, to assess the risk of corneal damage during and after the procedure. This evaluation allows the doctor to take appropriate precautions or consider alternative treatment options.

The test is performed using a specialized specular microscope that photographs the endothelial cell layer at high magnification. The instrument analyzes these images and provides data on cell density, size, and shape. The test is non invasive, painless, and typically does not require contact with the eye. It is relatively brief, usually lasting a few minutes for each eye.

No special preparation is needed for this test. Pupil dilation is generally not required, so blurred vision or glare is not expected afterward. It is important to inform your doctor about any previous eye surgeries, corneal injuries, or known eye diseases. In cases of significant corneal edema or cloudiness, it may be challenging to obtain a high quality and accurate image of the endothelial cells.

The number of endothelial cells naturally decreases with age. A low cell density, along with changes in cell size and shape, may indicate impaired corneal function and an increased risk of edema. The results are interpreted by the ophthalmologist in conjunction with other clinical findings, such as corneal thickness and the overall appearance of the eye. Based on these findings, a decision will be made regarding the need for follow up, further investigation, or appropriate treatment planning.