The cornea, which constitutes the bulk of the eye’s refractive power (45 D) and is approximately 550μm thick, consists of 5 different layers: Outwardly inward epithelial layer (50–60 μm), bowman layer (8–15 μm), stroma layer, desma layer (5– 10 μm) and the innermost endothelial layer.
The endothelium layer is composed of single-row hexagonal cells, and their number does not increase from birth and decreases with age and anterior segment diseases. In addition, there are serious reductions in the number of ophthalmic surgeries and especially in anterior segment surgeries. The dead cells are replaced by other cells by growing.
While there are approximately 3500 cells per millimeter in childhood, this number is between 2000 and 2500 cells / mm² at the age of 60–70.
Specular microscopy (endothelial cell count):
It is a test that counts the endothelial cell count of the patient’s corneal layer. Patients should be routinely administered before cataract surgeries. Especially, patients who have previously had anterior segment surgery or have endothelial insufficiency in the other eye after surgery should be given this test.
For safe cataract surgery, there must be a number above 1500 cells / mm². This number may be risky, especially in nigra cataracts and complicated cases. Therefore, additional measures must be taken to reduce the risk in such patients.
