View clinical trials related to Corneal Topography.
Filter by:Aim of the work: To study the corneal topographic pattern changes in patients who have pterygium excision by two surgical techniques (bare sclera, conjunctival autograft).
Contrast sensitivity (CS) and tear film (TF) changes are noted in late postoperative period after upper blepharoplasty (UB), while the same was rarely investigated in the early postoperative period. The reason for aforementioned improvement of vision quality is unclear. Suggested explanations include changes in higher-order aberrations, elimination of the overlay effect created by excess skin on the upper eyelids and/or eyelashes directed toward the eyelid, or changes in corneal topography (CT) and keratometry. Furthermore, there is no consensus on the best technique for UB. Due not only to different surgical techniques, but also to different methods of measuring the tear film quality, it is very difficult to quantify the aforementioned studies. While changes in tear volume parameters and changes in tear film (TF) rupture have been investigated in detail, changes in the lipid layer have rarely been investigated. According to previous studies, there are different findings about changes in CT after UB. The aim of the research is to determine whether there are anatomical (CT) and functional (TF and CS) changes in subjects with functional dermatochalasis before the procedure and in a month-long postoperative period. The research is conducted on examinees diagnosed by clinical examination with functional dermatochalasis with the exclusion of examinees with ocular or systemic conditions affecting TF, best corrected visual acuity or CT. Detailed medical history and ophthalmologic examination will be performed with grading of the external appearance of the upper eyelids. All diseases and conditions that can lead to changes in CS, TF or corneal defects will be noted. Preoperatively all subjects will have CS recorded in photopic conditions, TF analysis and CT (Keratograph 5M, OCULUS Optikgeraete GmbH, Wetzlar, Germany). UB will be performed in the operating room at the UED. At first (seven days postoperatively) and second (one month postoperative) check-up a CS check will be performed at the UED and TF analysis and CT at Lens LTD.
The purpose of this study is to quantify in-vivo repeatability of a new corneal topography measurement mode of an optical biometer, and the clinical performance of measurement in comparison to reference devices.