Abstract
Purpose: :
Get to know the existence of statistical reliability of endothelial cell samples obtained through to the corneal specular microscopy exam
Methods: :
retrospective study performed in 40 patients who had undergone corneal specular microscopy pre cataract surgery made in private clinic. The Bio–Optics specular microscopy was used with Bambi 2000 Plus software. The eyes were evaluated in relation to sex, age, endothelial density, variation coefficient and hexagonal cell percentual. The counted cell number in each specular microscopy image, considered as samples, were analyzed by CELLS ANALYZER – Corneal Endothelial Statistical Lab® with statistical power (confidence reliability (CR) of 90% and relative error (RE) of 0.1) with triage finality and diagnosis of morphometric endothelial cells variation and follow–up finalities (CR 95% and RE0.05)
Results: :
The sex distribution was 62 (52.1%) of the eyes of female patients and 57 (47.9%) of male patients. Minimum age was 57 years, maximum 84 years and the average 72±7 years. Minimum endothelial density was 1617 cell/mm²; maximum 3377 cell/mm² and average 2624±387 cell/mm²; minimum variation coefficient was 0.269, maximum 0.395 and average 0.321±0.043; minimum percentual hexagonal cells 39, maximum 62 and average 53.3±5.3; sample sizes: the smallest was 60 cells, the largest 135 cells and average 99.9±21.5 cells. To CR 90% and RE 0.1 the personalized sample size happened between 20 and 44 cells with average 29±6.5 cells; to make this statistical power all cells of the captured samples overflow the personalized sample size by CELLS ANALYZER® in 70±21.4%. To CR 95% and RE 0.05 the personalized sample sizes vary from 111 to 240 cells with average 160±35.5 cells; to this statistical power 95% of the samples did not overflow the necessary personalized sample sizes calculated by CELLS ANALYZER® and were 60±38% smaller than the necessary cell number.
Conclusions: :
the sample size of acquired endothelial cells for Bio–Optics specular microscopy to corneal endothelial triage was correct in 100% of the exams. It was efficient in only 10% of the eyes, for diagnosis and determination of endothelial morphometric caracteristics.
Keywords: cornea: endothelium • imaging/image analysis: clinical • cataract