scholarly journals Measuring Corneal Thickness with SOCT, the Scheimpflug System, and Ultrasound Pachymetry

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Ilona Piotrowiak ◽  
Beata Soldanska ◽  
Mateusz Burduk ◽  
Bartlomiej J. Kaluzny ◽  
Jozef Kaluzny
Keyword(s):  
Corneal Thickness ◽  
Moderate Agreement ◽  
Ultrasound Pachymetry ◽  
Repeatability And Reproducibility ◽  
The Mean

Background and Objective. Evaluation of agreement, repeatability, and reproducibility of central and minimal corneal thickness (CCT and MCT) measurements obtained by SOCT, the Scheimpflug system, and ultrasound pachymetry. Materials and Methods. 28 eyes of healthy patients were enrolled. Pachymetry measurements were performed with SOCT, the Scheimpflug system, and ultrasound instrument. Each measurement was taken by 3 operators on 3 devices providing a total of 2100 measurements. Results. The mean CCT for SOCT, Scheimpflug system, and ultrasound instrument was 537.92, 545.94, and 555.74 μm, respectively, (). The respective mean coefficients of repeatability for CCT were 0.61, 0.82 and 0.80, whereas mean coefficients of interoperator reproducibility for CCT were 0.91, 1.11, and 1.25. Conclusions. CCT and MCT measurements show moderate agreement between instruments. The repeatability and interoperator reproducibility of the results obtained by SOCT are somewhat higher. The operator's impact on CCT and MCT measurements is insignificant in all devices.

scholarly journals Precision of Corneal Thickness Measurements Obtained Using the Scheimpflug-Placido Imaging and Agreement with Ultrasound Pachymetry

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Jinhai Huang ◽  
Giacomo Savini ◽  
Chengfang Wang ◽  
Weicong Lu ◽  
Rongrong Gao ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Corneal Thickness ◽  
Intraclass Correlation ◽  
Normal Subjects ◽  
Limits Of Agreement ◽  
Ultrasound Pachymetry ◽  
Good Repeatability ◽  
Repeatability And Reproducibility ◽  
The Mean ◽  
Thickness Measurements

Purpose.To assess the reliability and comparability of measuring central corneal thickness (CCT) and thinnest corneal thickness (TCT) using a new Scheimpflug-Placido analyzer (TMS-5, Japan) and ultrasound (US) pachymetry.Methods.Seventy-six healthy subjects were prospectively measured 3 times by 1 operator using the TMS-5, 3 additional consecutive scans were performed by a second operator, and ultrasound (US) pachymetry measurements were taken. The test-retest repeatability (TRT), coefficient of variation (CoV), and intraclass correlation coefficient (ICC) were calculated to evaluate intraoperator repeatability and interoperator reproducibility. Agreement among the devices was assessed using Bland-Altman plots and 95% limits of agreement (LoA).Results.The intraoperators TRT and CoV were <19 μm and 2.0%, respectively. The interoperators TRT and CoV were <12 μm and 1.0%, respectively, and ICC was >0.90. The mean CCT and TCT measurements using the TMS-5 were 15.97 μm (95% LoA from −26.42 to −5.52 μm) and 20.32 μm (95% LoA from −30.67 to −9.97 μm) smaller, respectively, than those using US pachymetry.Conclusions.The TMS-5 shows good repeatability and reproducibility for measuring CCT and TCT in normal subjects but only moderate agreement with US pachymetry results. Caution is warranted before using these techniques interchangeably.

scholarly journals Comparison of Central Corneal Thickness Measurements between Angiovue Optical Coherence Tomography, Ultrasound Pachymetry and Ocular Biometry

2020 ◽  
pp. 1-9
Author(s):  
E. Pateras ◽  
A. I. Kouroupaki
Keyword(s):  
Optical Coherence Tomography ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Repeated Measurements ◽  
Optical Coherence ◽  
Swept Source ◽  
Ocular Biometry ◽  
Significant Linear Correlation ◽  
Ultrasound Pachymetry ◽  
The Mean

Purpose: To compare central corneal thickness (CCT) measurements and their reproducibility when taken by Ultrasound Pachymetry, Ocular Biometry and Angiovue Optical Coherence Tomography (OCT). Methods: Twenty-five healthy volunteers were recruited creating a sample size of 50 eyes. All subjects had pachymetric measurements by Ultrasound pachymetry (PachPen Handheld Pachymeter, Keeler Instruments Inc), Ocular biometry (IOL Master 700 Swept Source Biometry, Zeiss) and Angiovue Optical Coherence Tomography (Optovue Avanti RTVue XR Angiovue). The measurements of central corneal thickness for the three devices were taken by the same examiner twice for more accuracy. Results: The average measurements of central corneal thickness by Ultrasound pachymetry (PachPen Handheld Pachymeter, Keeler Instruments Inc), Ocular biometry (IOL Master 700 Swept Source Biometry, Zeiss) and Angiovue Optical Coherence Tomography (Optovue Avanti RTVue XR Angiovue) were 547.26 μm, 551.36 μm, and 536.42 μm, respectively. The mean standard deviation (SD) of repeated measurements by Ocular biometry was 48.87 μm, which was greater than the mean SD of 44.24 μm and 40.35 μm (P < 0.001) by ultrasound pachymetry and Angiovue optical coherence tomography, respectively. There were statistically significant differences in the measurement results among the 3 methods (Ultrasound pachymetry vs. Ocular biometry P = 0.019; Ultrasound pachymetry vs. Angiovue Optical Coherence Tomography; P < 0.001; Ocular biometry vs. Angiovue Optical Coherence Tomography P < 0.001). There was a significant linear correlation between the Ultrasound pachymetry and Ocular biometry (r = 0.945, P<0.001), Ultrasound pachymetry and Angiovue Optical Coherence Tomography (r = 0.895, P<0.001), and Ocular biometry and Angiovue Optical Coherence Tomography (r = 0.902, P<0.001). Conclusion: Central corneal thickness readings were comparable between PachPen Handheld Pachymeter, IOL Master 700 Biometry and Angiovue Optical Coherence Tomography; Angiovue optical coherence tomography gave significantly smaller values. The measurements of the 3 methods showed significant linear correlations with one another. All methods provided acceptable repeatability of measurements.

scholarly journals Central corneal thickness measurements in phakic, pseudophakic, and aphakic children with ultrasound pachymetry and different non-contact devices

2021 ◽  
Author(s):  
Majid Farvardin ◽  
Anis Shamsi ◽  
Amir Norouzpour ◽  
Mohammad-Hasan Jalalpour
Keyword(s):  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Partial Coherence ◽  
Specular Microscopy ◽  
Partial Coherence Interferometry ◽  
Ultrasound Pachymetry ◽  
Contact Devices ◽  
History Of ◽  
Aphakic Eyes ◽  
The Mean

Abstract Aims: Evidence for choosing a satisfactory device for central corneal thickness (CCT) measurement in children particularly pseudophakic and aphakic ones is insufficient. The aim of this study is to compare four differently-measured CCTs obtained using ultrasound pachymetry (UP), Pentacam, partial coherence interferometry (PCI), and specular microscopy (SM) in phakic, pseudophakic, and aphakic children and assess the agreement between the six pairs of the methods. Methods: Children with history of cataract surgery at age six or younger and phakic children were recruited into this study. CCT was measured using UP (Optikon 2000, Rome, Italy), Pentacam (Oculus Inc, Wetzlar, Germany), PCI (IOLMaster 700, Carl Zeiss Meditec AG, Jena, Germany), and SM (Topcon SP-3000P; Topcon Corporation, Japan).Results: One-hundred two eyes (53 phakic, 29 pseudophakic, and 20 aphakic eyes) were included. The mean ages (±SD) of phakic, pseudophakic, and aphakic cases were 9.75 (±3.3), 9.9 (±2.3), and 8.2 (±2.8) years respectively. The mean CCTs (±SE) for phakic children using Pentacam, PCI, UP, and SM were 549.7 (±5.0), 546.5 (±4.5), 565.9 (±5.5), and 506.2 (±4.4) mm respectively, for pseudophakic cases were 570.1 (±6.4), 565.0 (±6.1), 571.9 (±6.3), and 524.3 (±6.3) mm respectively, and for aphakic participants were 635.3 (±14.2), 635.4 (±14.5), 649.0 (±13.5), and 589.1 (±13.3) mm respectively. Conclusion: Compared to Pentacam and PCI, SM underestimated CCT particularly in phakic and pseudophakic children, whereas UP slightly overestimated CCT especially in phakic and aphakic children. Furthermore, Pentacam and PCI had the closest agreement. By contrast, SM had the poorest agreement with the other three methods.

scholarly journals Sirius Scheimpflug–Placido versus ultrasound pachymetry for central corneal thickness: meta-analysis

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Yili Jin ◽  
Colm McAlinden ◽  
Yong Sun ◽  
Daizong Wen ◽  
Yiran Wang ◽  
...  
Keyword(s):  
Central Corneal Thickness ◽  
Meta Analysis ◽  
Corneal Thickness ◽  
Mean Difference ◽  
Cochrane Library ◽  
Ultrasound Pachymetry ◽  
Significant Difference ◽  
The Mean ◽  
The Difference ◽  
Clinically Significant

Abstract Background To compare the difference in central corneal thickness (CCT) measurements in normal eyes between a rotating Scheimpflug camera combined with a Placido-disk corneal topographer (Sirius, CSO, Italy) and ultrasound pachymetry (USP). Methods A systematic literature search was conducted for relevant studies published on PubMed, Medline, EMBASE, and the Cochrane Library and ClinicalTrials.gov from inception to August 1st, 2019. Primary outcome measures were CCT measurements between Sirius and USP. A random effects model was used to pool CCT measurements. Results A total of twelve studies involving 862 eyes were included in this meta-analysis. The meta-analysis found CCT measurements between Sirius and USP to be statistically significantly different (P < 0.0001). The mean difference between Sirius and USP was −11.26 μm with a 95% confidence interval (CI) (−16.92 μm, −5.60 μm). The heterogeneity was I2 = 60% (P = 0.004). Conclusion CCT measurements with the Sirius Scheimpflug-Placido topographer were statistically significantly lower than USP. However, it may be argued that the mean difference of 11.26 μm is not a clinically significant difference.

scholarly journals Difference in Central Corneal Thickness between Applanation Ultrasound and Oculus Wave � 152 Light Occulyzer II

2019 ◽  
Vol 35 (3) ◽  
Author(s):  
Munira Shakir, Ronak Afza Memon Sahira Wasim Shakir Zafar
Keyword(s):  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Clinical Settings ◽  
Exclusion Criteria ◽  
Cross Sectional ◽  
Ultrasound Pachymetry ◽  
Department Of Ophthalmology ◽  
The Mean ◽  
Thickness Measurements ◽  
Applanation Ultrasound

Purpose: To determine the mean difference of central corneal thickness measurements by using ultrasound Pachymetry and oculus Wave light Occulyzer II. Study Design: Cross-sectional comparative study using non-probability consecutive sampling. Place and Duration of Study: This study was conducted at Department of Ophthalmology, Liaquat National Hospital Karachi from November 2018 to June 2019. Material & Methods: After approval from ethical committee, patients were included in our study on the basis of inclusion & exclusion criteria. Central corneal thickness measurements were taken by using ultrasound Pachymetry & oculus Wave light Occulyzer II. All the data was collected by single researcher. The results were plotted, compared & analyzed. Paired t-test was used for the comparison of quantitative variables. Results: There were 130 patients included in the study out of which 73 (56.2%) were males and 57 (43.8%) were females. Mean age of these patients was 33.9 � 8.9 years. The mean � SD thinnest oculus Wave light Occulyzer II measurement was 538.61 � 23.46 ?m and ranged between 476.0 and 619.0 ?m whereas the mean thinnest ultrasound Pachymetry measurement was 535.1 � 21.816 ?m and ranged between 482 and 601 ?m. There was highly significant correlation of central corneal thickness between both the instruments. (r = 0.96, p < 0.001). Conclusion: There is a high correlation of central corneal thickness between the readings obtained from ultrasound and optical pachymetry machines therefore oculus Wave light Occulyzer II can be used as an alternative technique to ultrasound pachymetry while assessing CCT in clinical settings. Key Words: Central corneal thickness, Ultrasound Pachymetry, Optical Pachymetry.

scholarly journals Evaluation of Central Corneal Thickness Using Corneal Dynamic Scheimpflug Analyzer Corvis ST and Comparison with Pentacam Rotating Scheimpflug System and Ultrasound Pachymetry in Normal Eyes

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Ayong Yu ◽  
Weiqi Zhao ◽  
Giacomo Savini ◽  
Zixu Huang ◽  
Fangjun Bao ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Coefficient Of Variation ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Intraclass Correlation ◽  
Limits Of Agreement ◽  
Corvis St ◽  
Ultrasound Pachymetry ◽  
Repeatability And Reproducibility ◽  
High Repeatability

Purpose.To assess the repeatability and reproducibility of central corneal thickness (CCT) measurements by corneal dynamic Scheimpflug analyzer Corvis ST in normal eyes and compare the agreement with Pentacam rotating Scheimpflug System and ultrasound pachymetry.Methods.84 right eyes underwent Corvis ST measurements performed by two operators. The test-retest repeatability (TRT), within-subject coefficient of variation (CoV), and intraclass correlation coefficient (ICC) were used to evaluate the intraoperator repeatability and interoperator reproducibility. CCT measurements also were obtained from Pentacam and ultrasound pachymetry by the first operator. The agreement between the three devices was evaluated with 95% limits of agreement (LoA) and Bland-Altman plots.Results.Corvis ST showed high repeatability as indicated by TRT ≤ 13.0 μm, CoV < 0.9%, and ICC > 0.97. The interoperator reproducibility was also excellent. The CoV was <0.9%, and ICC was >0.97. Corvis ST showed significantly lower values than Pentacam and ultrasound pachymetry (P<0.001). The 95% LoA between Corvis ST and Pentacam or ultrasound pachymetry were −15.8 to 9.5 μm and −27.9 to 12.3 μm, respectively.Conclusions.Corvis ST showed excellent repeatability and interoperator reproducibility of CCT measurements in normal eyes. Corvis ST is interchangeable with Pentacam but not with ultrasound pachymetry.

scholarly journals Reproducibility of Central Corneal Thickness Measurements in Normal Eyes Using the Zeiss Cirrus 5000 HD-OCT and Pentacam HR

2018 ◽  
Vol 12 (1) ◽  
pp. 72-83 ◽  
Author(s):  
Elmira Baghdasaryan ◽  
Xiwen Huang ◽  
Kenneth M. Marion ◽  
Tudor C. Tepelus ◽  
Homayoun Bagherinia ◽  
...  
Keyword(s):  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Segment ◽  
Test Analysis ◽  
Cirrus Oct ◽  
Repeatability And Reproducibility ◽  
The Mean ◽  
Highly Correlated ◽  
Thickness Measurements ◽  
Intra Class Correlation Coefficient

Objectives:To determine the repeatability and reproducibility of Central Corneal Thickness (CCT) measurements using two different anterior segment imaging modalities, including those obtained with the new anterior segment lens attachments for the Cirrus 5000 HD-OCT.Methods:A total of 32 eyes from 16 normal volunteers (8 male, 8 female) were enrolled in this prospective study. CCT was measured by the same examiner using the Cirrus 5000 HD-OCT and Pentacam HR. The results of CCT obtained by each method were averaged and compared using t-test analysis. The agreement between the measurement methods was evaluated. Coefficient of Repeatability (CoR) and Intra-Class Correlation Coefficient (ICC) were computed.Results:The mean measurements taken with the Cirrus OCT anterior chamber lens (CCTAC), HD cornea lens (CCTHDC) and pachymetry scans (CCTPach) were 545.35 ± 31.02, 537.87 ± 26.82, and 532.04 ± 29.82 µm, respectively. The mean CCT obtained with the Pentacam (CCTPent) was 545.51 ± 30.71 µm. CCTPentwere significantly higher than CCTHDCand CCTPach(p< 0.0001). In contrast, the CCTPentand CCTACwere similar (p=0.87). CCT, as evaluated by the two different instruments, showed excellent correlation (r> 0.98,p< 0.0001) with an ICC > 0.99 (95% CI, 0.97 – 0.99). CoR was the highest for CCTPach(3.7 ± 1.4, 95% CI (3.0- 4.6)).Conclusion:CCT measurements from the Cirrus OCT using the new anterior segment lens attachments and the Pentacam HR are highly correlated. This should allow the use of a standardized correction factor if necessary to inter-relate the measurements between the two devices.

scholarly journals CENTRAL CORNEAL THICKNESS

2018 ◽  
Vol 25 (02) ◽  
pp. 252-260
Author(s):  
Muhammad Ijaz Ahmad ◽  
Manzoor Ahmad Qureshi ◽  
Muhammad Shakeel Ahmad ◽  
Yousef Homood Aldebasi
Keyword(s):  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Mean Value ◽  
T Test ◽  
Kingdom Of Saudi Arabia ◽  
Cross Sectional ◽  
Ultrasound Pachymetry ◽  
Significant Difference ◽  
The Mean ◽  
Ultrasonic Pachymetry

Objectives: To compare central corneal thickness in myopic and keratoconuseyes by ultrasound pachymetry and pentacam HR. Study Design: Cross sectional study.Setting: Qassim University, Optometry Clinics, Kingdom of Saudi Arabia. Period: October2016 to April 2017. Methodology: One hundred myopic and keratoconus participants. CentralCorneal Thickness (CCT) were measured with two techniques by ultrasonic pachymetry andpentacam HR in two groups. Group one consisted of 80 myopic participants and group two of 20Keratoconuspatients.Pentacamreadings were recorded first. CCT were compared and analyzedstatistically using unpaired t-test and histogram. Results: One hundred participants (100) wereincluded in which 80 participants were myopic and 20 with keratoconus. Both eyes (200) of allthe participants were examined. Age of the myopics ranged from 18-30 years (Mean=23.03).The mean value with ultrasound pachymetery was 555μm (SD±32.021) and with pentacam566μm (SD±37.367). We observed a tendency of overestimation of CCT measurements withpentacam. Statistically a significant difference of reading between two devices (P<0.001) wasfound. In keratoconus participants, the mean age was 23.7 years (21- 26). The mean CCT takenwith Pentacam HR and US Pachymetry was 476μm (SD± 16.980) and 465μm (SD± 35.868)respectively. The t-test showed no statistical difference between thepentacam HR andultrasound pachymetry (p>0.214). Conclusion: Measurements of central corneal thicknessdone with Ultrasound Pachymeter and Pentacam HR are closely related to each other andare interchangeable when used in normal refractive error cases. While in Keratonus patientsultrasound pachymetry is preferred because of its reliability.

Long term results of accelerated corneal collagen cross-linking in pediatric keratoconus

2021 ◽  
pp. 112067212110183
Author(s):  
Yasin Cinar ◽  
Cagla Cilem Han ◽  
Alparslan Sahin ◽  
Zeba A Syed
Keyword(s):  
Visual Acuity ◽  
Corneal Thickness ◽  
University Hospital ◽  
Long Term Results ◽  
Cross Linking ◽  
Distance Visual Acuity ◽  
The Mean ◽  
Collagen Cross Linking ◽  
Corneal Collagen

Purpose: To evaluate the long term visual, refractive, and corneal tomographic outcomes of epithelium-off accelerated corneal collagen cross-linking (ACXL) in the management of pediatric keratoconus (KC). Methods: This retrospective study included patients under 18 years old with progressive KC who underwent ACXL between 2012 and 2019 at Dicle University Hospital. Complete ophthalmic examination was performed including uncorrected distance visual acuity (UDVA), best spectacle-corrected distance visual acuity (CDVA), manifest refraction, and corneal tomography. Evaluations were performed preoperatively and at 6 months intervals postoperatively. Results: Forty-nine eyes of 49 patients were included in the study. The mean age of patients at the time of ACXL was 14.2 ± 1.8 (range: 9.5–17.3) years. Mean follow up was 4.61 ± 1.90 (range: 2.0–8.1) years. The mean LogMAR UDVA improved from 0.94 ± 0.41 to 0.81 ± 0.43, 0.69 ± 0.41, and 0.67 ± 0.33 after 1, 3, and 5 years respectively ( p = 0.001). The mean LogMAR CDVA improved from 0.58 ± 0.36 to 0.46 ± 0.31, 0.34 ± 0.23, and 0.39 ± 0.27 after 1, 3, and 5 years respectively ( p = 0.015). The mean refractive cylinder improved significantly from 6.01 ± 2.07 diopters (D) to 5.46 ± 1.87, 5.38 ± 2.18, and 5.02 ± 2.31 D after 1, 3, and 5 years respectively ( p = 0.005). As compared to preoperative values, steep keratometry and maximum keratometry were not significantly different ( p = 0.805 and 0.448, respectively) following ACXL, while flat keratometry significantly improved after ACXL ( p = 0.012). Although central corneal thicknesses decreased significantly ( p = 0.029), the decrease in thinnest corneal thickness was not statistically significant ( p = 0.205). Conclusion: Epithelium-off ACXL seems to be effective for halting KC progression with long term clinical benefits in pediatric patients.

scholarly journals A hospital-based study on clinical data, demographic data and visual function of keratoconus patients in Central China

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kaili Yang ◽  
Liyan Xu ◽  
Qi Fan ◽  
Yuwei Gu ◽  
Bo Zhang ◽  
...  
Keyword(s):  
Clinical Data ◽  
Rural Areas ◽  
Visual Function ◽  
Urban Areas ◽  
Demographic Data ◽  
Corneal Thickness ◽  
Positive Family History ◽  
Education Level ◽  
Central China ◽  
The Mean

AbstractChina is a populous country but lacks epidemiological data on keratoconus (KC). The present study aimed to investigate the clinical data, demographic data, and visual function (VF) data of KC patients in Central China. A total of 524 KC eyes in 307 KC patients (217 bilateral and 90 unilateral) from Henan Eye Hospital were included in the current study. Demographic and VF data were assessed with questionnaires administered by well-trained staff during face-to-face interviews. Visual acuity value was examined by a qualified optometrist, and the clinical data were measured by professional clinicians. The distributions of sex, residence and education level of KC patients were compared by Chi-square tests, and the ratios of people wearing glasses and rigid gas permeable (RGP) lenses were compared by McNemar tests. General linear models/Chi-squared tests were used to compare the clinical and demographic data according to KC severity. Spearman’s correlation analysis was used to test the associations between the data and KC severity. The mean age at diagnosis was 20.98 ± 6.06 years, and males had a higher ratio of KC than females (P < 0.001). Patients in rural areas had a higher rate of KC than those in urban areas (P = 0.039), and the proportion of KC patients with a higher education level (above high school) was high (P < 0.001). A total of 68.40% of the patients reported eye rubbing and 3.52% had a positive family history. The percentage of people wearing glasses was higher than that of patients wearing RGP lenses (P < 0.001). The total VF score of KC patients was 69.35 ± 15.25. The thinnest corneal thickness (TCT) and stiffness parameter at the first applanation (SP-A1) values were inversely correlated with KC severity (P < 0.05). The mean, steep, and max keratometry (Km, Ks and Kmax) values, the RGP lens use and keratoplasty were positively correlated with KC severity (all P < 0.05). The total VF score of the eye with better VA decreased as the severity increased (r = − 0.21, P = 0.002). The present study comprehensively describes various associated features of KC patients from a tertiary hospital in Central China, providing a reference for understanding the characteristics of KC patients in China.

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