scholarly journals Comparison of Four Methods for Corneal Thickness Measurement

2013 ◽  
Vol 6 (1) ◽  
pp. 37-42
Author(s):  
Teodora L. Marinova ◽  
Vesela Ivancheva ◽  
Svilena S. Peeva ◽  
Christina N. Grupcheva

Summary The aim of the study was to evaluate the thickness of the normal cornea in order to establish correlation between four methods of measuring including: ultrasound pachymetry (USP), anterior segment optical coherence tomography (ASOCT), non-contact tono/pachymetry (TONOPACHY) and laser-scanning confocal microscopy (LSCM). The study was based on evaluating repeatability and comparability of four different methods formeasuring the corneal thickness. Non contact specular microscopy was first performed on all 27 patients (aged between 20 and 24 years) to evaluate corneal characteristics and confirm the absence of pathological changes. Each participant was examined by USP, ASOCT and TONOPACHY, and 13 eyes of 10 persons were also examined by LSCM. The values of average central corneal thickness measured by USP, ASOCT, TONOPACHY and LSCM were 532.20±4.5 pm, 553.33±12.1 pm, were 548.20±5.62 pm and 573.33±7.22 pm, respectively. There was a high correlation between the instruments. The mean differences for central corneal thickness measurements were 41.43±1.67 pm between USP and LSCM, 20.43±2.4 pm between USP and ASOCT, and 22.1 ±3.88 pm between USB and TONOPACHY. Anterior segment optical coherence tomography overestimated corneal thickness as compared with that measured by USP, which is believed to be a gold standard. Anterior segment optical coherence tomography had better agreement with USP, as compared with LSCM. However, the results of measured cornea thickness by TONOPACHY were very close to cornea thickness measured by ASOCT.

Author(s):  
Sagili Chandrasekhara Reddy ◽  
Mohd Mansor Shariff ◽  
Aina Malindri Dasrilsyah

Purpose: To determine the central corneal thickness in myopic adult patients scheduled for laser corneal refractive surgery and to explore its correlation with degree of refractive error. Materials and Methods: The case records of 130 myopic patients who underwent laser corneal refractive surgery in a military hospital over a period of two years were reviewed to determine the central corneal thickness. All patients had 6/6 vision with best correction, and did not have any other anterior segment or fundus diseases in both eyes. The central corneal thickness was measured with Visante Carl Zeiss anterior segment optical coherence tomography instrument.                                                                                                                        Results: Out of 130 patients, males were more (73, 56.2%); mean age of patients was 33.8 years (range 18-60 years) and majority were Malays (110, 84.6%).  The spherical power of myopia ranged from – 0.5 to – 10.00 D, and the cylindrical power ranged from – 0.25 to – 3.25 D. The mean central corneal thickness of both eyes was 528.2 µm (range 331- 615 µm); in the mild degree of myopia (- 0.50 to - 2.00 D) 527.9 µm, moderate degree (- 2.25 to -5.00 D) 529.4 µm, and high degree (-5.25 to -11.00 D) 523.9 µm. Conclusion: The anterior segment optical coherence tomography provides noncontact, rapid, pachymetry mapping of the corneal thickness. In Malaysian patients, the mean central corneal thickness of both eyes in myopia was 528.1 µm (range 331- 615 µm). There was no correlation between the mean central corneal thickness and degree of myopia, different genders, age groups, ethnic groups and two eyes.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Thiago Trindade Nesi ◽  
Daniel Amorim Leite ◽  
Fábio Medina Rocha ◽  
Marco Antônio Tanure ◽  
Pedro Paulo Reis ◽  
...  

Optical coherence tomography (OCT) of the anterior segment, in particular corneal OCT, has become a reliable tool for the cornea specialist, as it provides the acquisition of digital images at high resolution with a noncontact technology. In penetrating or lamellar keratoplasties, OCT can be used to assess central corneal thickness and pachymetry maps, as well as precise measurements of deep stromal opacities, thereby guiding the surgeon to choose the best treatment option. OCT has also been used to evaluate the keratoplasty postoperative period, for early identification of possible complications, such as secondary glaucoma or donor disc detachments in endothelial keratoplasties. Intraoperatively, OCT can be used to assess stromal bed regularity and transparency in anterior lamellar surgeries, especially for those techniques in which a bare Descemet’s membrane is the goal. The purpose of this paper is to review and discuss the role of OCT as a diagnostic tool in various types of keratoplasties.


2018 ◽  
Vol 16 (1) ◽  
pp. 25-31
Author(s):  
Patricia González-Rodríguez ◽  
Vanesa Blázquez-Sánchez ◽  
Sara Fernández-Cuenca

Objective: To study and compare the value of central corneal thickness in a healthy adult population, using different non-contact techniques from daily clinical practice. Method: This work examines and compares the pachymetric measurements of 71 eyes of 36 healthy adult patients. Corneal thickness was evaluated using three non-contact instruments: a CEM-530 specular microscope (Nidek), Pentacam HR corneal tomography (Oculus), and Cirrus HD-OCT 5000 optical coherence tomography (Carl Zeiss Meditec). Tests were performed consecutively by a single observer in the same session and under the same environmental conditions. Results: The results obtained using the three devices are interchangeable, given that no statistically significant difference was observed among them. The study did not find statistically significant difference with respect to gender either. Conclusion: These three non-contact methods for the measurement of corneal central pachymetry are a reliable alternative to ultrasonic contact pachymetry.


Cornea ◽  
2011 ◽  
Vol 30 (2) ◽  
pp. 121-126 ◽  
Author(s):  
Harsha Laxmana Rao ◽  
Addepalli Uday Kumar ◽  
Anjul Kumar ◽  
Swathi Chary ◽  
Sirisha Senthil ◽  
...  

Ophthalmology ◽  
2008 ◽  
Vol 115 (5) ◽  
pp. 796-801.e2 ◽  
Author(s):  
Haitao Li ◽  
Christopher Kai Shun Leung ◽  
Lee Wong ◽  
Carol Yim Lui Cheung ◽  
Chi Pui Pang ◽  
...  

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