scholarly journals Quantitative analysis of the iris surface smoothness by spectral domain optical coherence tomography in Fuchs uveitis

2020 ◽  
Author(s):  
Mohammad Zarei ◽  
Elias Khalili Pour ◽  
Nazanin Ebrahimiadib ◽  
Hamid Riazi-Esfahani
Keyword(s):  
Optical Coherence Tomography ◽  
Quantitative Analysis ◽  
Anterior Segment ◽  
Optical Coherence ◽  
Actual Length ◽  
Straight Line ◽  
Smoothness Index ◽  
The Mean ◽  
Imagej Software ◽  
Fellow Eyes

AbstractPurposeTo demonstrate the value of “smoothness index” as a novel tool for quantitative analysis of iris surface findings in unilateral Fuchs’ uveitis (FU).MethodsIn this observational study, both phakic eyes from patients with the diagnosis of unilateral FU were enrolled. All eyes underwent a complete ophthalmic examination and anterior segment optical coherence tomography(AS-OCT). The images were extracted and exported to the ImageJ software for calculating the “smoothness index (SI)”. The SI was defined as ratio of length of the straight line connecting the most peripheral and the most central points of anterior iris surface to actual length of this boundary.ResultsForty eyes from 20 patients with unilateral FU were enrolled. Mean age of patients was 40±10 years. Mean overall SI was 0.876± 0.030 in eyes with FU that was significantly more than fellow control eyes (0.841± 0.041). (p=0.005) The mean temporal and nasal SI were 0.878± 0.035 and 0.874± 0.033 in eyes with FU, compared to 0.843± 0.041 and 0.838± 0.047 in control fellow eyes, respectively. (p = 0.008 and p = 0.009, respectively)ConclusionIris “smoothness index” is a novel index to quantitatively document diffuse smoothness of iris anterior surface in eyes with FU. This index may facilitate diagnosis of subtle iris atrophic changes in these eyes, especially when heterochromia is absent.

scholarly journals Automated measurement of iris surface smoothness using anterior segment optical coherence tomography

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mohammad Zarei ◽  
Tahereh Mahmoudi ◽  
Hamid Riazi-Esfahani ◽  
Behnam Mousavi ◽  
Nazanin Ebrahimiadib ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Correlation Coefficient ◽  
Anterior Segment ◽  
Control Group ◽  
Optical Coherence ◽  
Actual Length ◽  
Interclass Correlation Coefficient ◽  
Interclass Correlation ◽  
Automated Measurements ◽  
Fellow Eyes

AbstractFuchs uveitis (FU) is a chronic and often unilateral ocular inflammation and characteristic iris atrophic changes, other than heterochromia, are common in FU and are key to the correct diagnosis in many cases. With the advent of anterior segment optical coherence tomography (AS-OCT), some investigators attempted to quantitatively study these atrophic changes; mostly by introducing various methods to measure iris thickness in AS-OCT images. We aimed to present an automated method in an observational case series to measure the smoothness index (SI) of the iris surface in AS-OCT images. The ratio of the length of the straight line connecting the most peripheral and central points of the anterior iris border (in nasal and temporal sides) to the actual length of this border on AS-OCT images, was defined as SI. In a uveitis referral center, twenty-two eyes of 11 patients with unilateral Fuchs uveitis (FU) (7 female) and 22 eyes of 11 healthy control subjects underwent AS-OCT imaging. Image J and a newly developed MATLAB algorithm were used for manual and automated SI measurements, respectively. Agreement between manual and automated measurements was evaluated with Bland–Altman analysis and interclass correlation coefficient. The inter-eye difference of SI was compared between the FU group and the control group. Automated mean overall SI was 0.868 ± 0.037 and 0.840 ± 0.039 in FU and healthy fellow eyes, respectively (estimated mean difference =  − 0.028, 95% CI [− 0.038, − 0.018], p < 0.001). Bland- Altman plots showed good agreement between two methods in both healthy and FU eyes. The interclass correlation coefficient between the manual and automated measurements in the FU and healthy fellow eyes was 0.958 and 0.964, respectively. The inter-eye difference of overall SI was 0.029 ± 0.015 and 0.012 ± 0.008 in FU group and control group, respectively (p = 0.01). We concluded that the automated algorithm can rapidly and conveniently measure SI with results comparable to the manual method.

scholarly journals Changes in anterior segment optical coherence tomography following pars plana vitrectomy without tamponade

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Alireza Khodabande ◽  
Massood Mohammadi ◽  
Hamid Riazi-Esfahani ◽  
Shahab Karami ◽  
Massood Mirghorbani ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Anterior Chamber ◽  
Pars Plana Vitrectomy ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Optical Coherence ◽  
Mean Values ◽  
Iop Measurement ◽  
Pars Plana ◽  
The Mean

Abstract Background To evaluate changes in anterior segment morphology on anterior segment optical coherence tomography (AS-OCT) following pars plana vitrectomy (PPV) without tamponade. Methods Patients who underwent PPV without tamponade for epiretinal membrane were evaluated. Eligible patients underwent intraocular pressure (IOP) measurement and AS-OCT preoperatively as well as 1 month and 6 months post-operatively. Anterior chamber width (ACW), anterior chamber depth (ACD), trabecular iris angle (TIA), angle opening distance at 500 and 750 µm (AOD), and trabecular iris space area at 500 and 750 µm (TISA) at four quadrants were recorded and analyzed. Additionally, the mean values of TIA (MTIA), AOD (MAOD), and TISA (MTISA) for each eye (mean of four quadrants) were analyzed. Results 23 patients completed the study. The mean age of participants was 56.4 ± 3.6 years of age and 13/23 (56%) were female. Mean IOP of patients was 18.1 ± 1.1, 18.3 ± 1.1, and 18.1 ± 1.2 preoperatively,1 month post-operatively, and 6 months post-operatively, respectively. (p = 0.83). No difference was detected post-operatively in measurements of ACW, ACD, MTIA, MAOD500, MAOD750, MTISA500, and MTISA750. Conclusion Pars plana vitrectomy without tamponade was not associated with changes in anterior chamber morphology.

scholarly journals Correlation between Central Corneal Thickness and Degree of Myopia among Malaysian Patients Undergoing Laser Keratorefractive Surgery

2020 ◽  
pp. 52-58
Author(s):  
Sagili Chandrasekhara Reddy ◽  
Mohd Mansor Shariff ◽  
Aina Malindri Dasrilsyah
Keyword(s):  
Optical Coherence Tomography ◽  
Refractive Surgery ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Segment ◽  
Military Hospital ◽  
Moderate Degree ◽  
Optical Coherence ◽  
Corneal Refractive Surgery ◽  
The Mean

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.

Anterior chamber particles are associated with reduction of intraocular pressure after selective laser trabeculoplasty

2020 ◽  
pp. bjophthalmol-2019-315445
Author(s):  
Alexei N Kulikov ◽  
Dmitrii S Maltsev ◽  
Alina A Kazak ◽  
Maria A Burnasheva
Keyword(s):  
Optical Coherence Tomography ◽  
Intraocular Pressure ◽  
Anterior Chamber ◽  
Open Angle Glaucoma ◽  
Anterior Segment ◽  
Optical Coherence ◽  
Selective Laser Trabeculoplasty ◽  
Cross Sectional ◽  
Laser Trabeculoplasty ◽  
The Mean

PurposeTo study the correlation between intraocular pressure (IOP) reduction and the number of hyper-reflective particles appearing in the anterior chamber following selective laser trabeculoplasty (SLT).Material and methodsIn this prospective interventional study, we included primary open-angle glaucoma patients. All participants received a standardised SLT session, which consisted of 100 pulses of 0.9 mJ over 360°. Anterior segment optical coherence tomography (4×4 mm volume scan, 101 horizontal cross-sectional scans) and applanation tonometry were performed before SLT and 15 min, 1 day, 1 week, 1 month and 3 months after. Particles were counted on cross-sectional scans using a standardised algorithm.ResultsIn this study, we included 25 patients (25 eyes), 14 males and 11 females, with a mean age of 68.9±10.5 and baseline IOP of 21.4±4.5 mm Hg. IOP at month 1 and month 3 after SLT was 18.0±4.0 and 17.4±3.3 mm Hg, respectively. The mean number of anterior chamber particles before and 15 min after SLT was 0.62±0.2 and 7.1±2.0 particles/mm2, respectively (p=0.036). There was a statistically significant correlation between the mean number of anterior chamber particles 15 min after SLT and IOP reduction at 1 month (r=0.62, p=0.03) and 3 months (r=0.71, p=0.01).ConclusionThe number of the anterior chamber particles graded using anterior segment optical coherence tomography after the procedure correlates with the IOP-lowering effect of SLT.

scholarly journals Automated Measurement of Iris Surface Smoothness Using Anterior Segment Optical Coherence Tomography  

2021 ◽  
Author(s):  
Mohammad Zarei ◽  
Tahereh Mahmudi ◽  
Hamid Riazi-Esfahani ◽  
Behnam Mousavi ◽  
Nazanin Ebrahimiadib ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Correlation Coefficient ◽  
Anterior Segment ◽  
Control Group ◽  
Optical Coherence ◽  
Interclass Correlation Coefficient ◽  
Interclass Correlation ◽  
Automated Measurements ◽  
And Control ◽  
Fellow Eyes

Abstract Fuchs uveitis (FU) is a chronic and often unilateral ocular inflammation and characteristic iris atrophic changes, other than heterochromia, are common in FU and are key to the correct diagnosis in many cases. With the advent of anterior segment optical coherence tomography (AS-OCT), some investigators attempted to quantitatively study these atrophic changes; mostly by introducing various methods to measure iris thickness in AS-OCT images. We aimed to present an automated method in a observational case series to measure the smoothness index (SI) of iris surface in AS-OCT images. The ratio of the length of the straight line connecting the most peripheral and central points of the anterior iris border (in nasal and temporal sides) to the actual length of this border on AS-OCT images, was defined as SI. In a uveitis referral center twenty-two eyes of 11 patients with unilateral Fuchs uveitis (FU) (7 female) and 22 eyes of 11 healthy control subjects underwent AS-OCT imaging. Image J and a newly developed MATLAB algorithm were used for manual and automated SI measurements, respectively. Agreement between manual and automated measurements was evaluated with Bland-Altman analysis and interclass correlation coefficient. The inter-eye difference of SI was compared between FU group and control group. Automated mean overall SI was 0.868 ± 0.037 and 0.840 ± 0.039 in FU and healthy fellow eyes, respectively (estimated mean difference = -0.028, 95% CI [-0.038, -0.018], p<0.001). Bland- Altman plots showed good agreement between two methods in both healthy and FU eyes. Interclass correlation coefficient between the manual and automated measurements in the FU and healthy fellow eyes was 0.958 and 0.964, respectively. Inter-eye difference of overall SI was 0.029 ± 0.015 and 0.012 ± 0.008 in FU group and control group, respectively (p=0.01). We concluded that he automated algorithm can rapidly and conveniently measure SI with results comparable to manual method.

scholarly journals Quantitative Analysis of Lens Nuclear Density Using Optical Coherence Tomography (OCT) with a Liquid Optics Interface: Correlation between OCT Images and LOCS III Grading

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
You Na Kim ◽  
Jin Hyoung Park ◽  
Hungwon Tchah
Keyword(s):  
Optical Coherence Tomography ◽  
Anterior Segment ◽  
Nuclear Density ◽  
Optical Coherence ◽  
Pixel Intensity ◽  
Age Related ◽  
Corrected Distance Visual Acuity ◽  
Positive Linear Correlation ◽  
Lens Opacities ◽  
Imagej Software

Purpose. To quantify whole lens and nuclear lens densities using anterior-segment optical coherence tomography (OCT) with a liquid optics interface and evaluate their correlation with Lens Opacities Classification System III (LOCS III) lens grading and corrected distance visual acuity (BCVA).Methods. OCT images of the whole lens and lens nucleus of eyes with age-related nuclear cataract were analyzed using ImageJ software. The lens grade and nuclear density were represented in pixel intensity units (PIU) and correlations between PIU, BCVA, and LOCS III were assessed.Results. Forty-seven eyes were analyzed. The mean whole lens and lens nuclear densities were 26.99 ± 5.23 and 19.43 ± 6.15 PIU, respectively. A positive linear correlation was observed between lens opacities (R2= 0.187,p<0.01) and nuclear density (R2= 0.316,p<0.01) obtained from OCT images and LOCS III. Preoperative BCVA and LOCS III were also positively correlated (R2= 0.454,p<0.01).Conclusions. Whole lens and lens nuclear densities obtained from OCT correlated with LOCS III. Nuclear density showed a higher positive correlation with LOCS III than whole lens density. OCT with a liquid optics interface is a potential quantitative method for lens grading and can aid in monitoring and managing age-related cataracts.

Accuracy of the indices of MS-39 anterior segment optical coherence tomography in the diagnosis of keratoconic corneas

2021 ◽  
pp. 112067212110637
Author(s):  
Rania S Elkitkat ◽  
Yasser Rifay ◽  
Hesham M Gharieb ◽  
Hossam Eldin A Ziada
Keyword(s):  
Optical Coherence Tomography ◽  
Anterior Segment ◽  
Front Surface ◽  
Receiver Operating Curve ◽  
P Value ◽  
Optical Coherence ◽  
Corneal Surface ◽  
Cross Sectional ◽  
The Mean ◽  
Group 2

Purpose To determine the normative and the cut-off values of various indices available in the MS 39 Anterior Segment Optical Coherence Tomography (MS-39 AS-OCT) for keratoconus (KC) diagnosis, and to detect the accuracy of the variable available parameters. Methods This cross sectional observational study was conducted at Dr Rifay Ophthalmology Center, Rabat, Morocco, on 172 eyes with KC (group 1) and 248 eyes of healthy controls (group 2). Participants were screened using MS-39 AS-OCT (CSO, Firenze, Italy). The investigated indices included: keratometric indices, pachymetric indices, elevation indices, Keratoconus Summary Indices (KSI), aberration indices, and epithelial mapping evaluation. Results Most of the studied indices were significantly different between both groups (P value <0.001). Twenty two indices had Area Under the Receiver Operating Curve (AUROC) values >0.950, eight of which were from the KSI. The indices with the highest AUROC values were: Root Mean Square (RMS) for the front corneal surface at 6 mm circle (AUROC = 0.996, and best cut-off >1.69 with sensitivity of 97.67% and specificity of 97.98%) and RMS per unit of area for the front surface at 6 mm circle (AUROC = 0.996, and best cut-off >0.06 with sensitivity of 97.67% and specificity of 97.98%). Epithelial thickness-derived metrics were not among the parameters with the highest accuracy. Conclusions This study presented the mean and the cut-off values for a plethora of parameters available in the MS-39 AS-OCT. The results of this study show that MS-39 AS-OCT is a valuable equipment for diagnosing keratoconic corneas, with a high accuracy detected for many parameters.

scholarly journals Pterygia measurements are more accurate with anterior segment optical coherence tomography - A pilot study

1970 ◽  
Vol 3 (1) ◽  
pp. 9-12 ◽  
Author(s):  
MN Welch ◽  
CD Reilly ◽  
K Kalwerisky ◽  
A Johnson ◽  
SG Waller
Keyword(s):  
Optical Coherence Tomography ◽  
Standard Deviation ◽  
Pilot Study ◽  
Clinical Assessment ◽  
Anterior Segment ◽  
Optical Coherence ◽  
Slit Lamp ◽  
Significant Difference ◽  
The Mean ◽  
The Difference

Introduction: Slit-lamp beam measurements of a pterygium can be difficult to reproduce accurately. Purpose: To compare standard slit-lamp beam measurements of pterygia to computer caliper measurements of Anterior Segment Optical Coherence Tomography (OCT) images. Subjects and methods: Thirteen pterygia of ten patients were evaluated. Two physicians independently measured each pterygium using the slit lamp beam. Caliper measurements of two different OCT images of each pterygium were obtained. All measurements determined the distance from the limbus to the pterygium apex. Results: The difference in the slit lamp beam measurements of each pterygium was calculated and the mean of the differences was 0.3 and the standard deviation was 0.32. The difference in the two OCT measurements of each pterygium was also calculated and the mean of the differences was 0.1 and the standard deviation was 0.12. A two-tailed t-test demonstrated a statistically significant difference in these measurements (p = 0.0256). Conclusion: Anterior Segment Optical Coherence Tomography (OCT) gives significantly more reproducible results than the slit lamp beam for measurements of the distance of a pterygium’s apex from the limbus. This tool may provide more accurate clinical assessment of extension of pterygia onto the cornea and may be useful for research purposes. Key words: pterygium; pterygia; anterior segment optical coherence tomography; OCT DOI: 10.3126/nepjoph.v3i1.4271Nepal J Ophthalmol 2011;3(5):9-12

scholarly journals Pachychoroid as a biomarker using optical coherence tomography – swept-source in central serous choroidopathy

2019 ◽  
Vol 2 ◽  
pp. 3
Author(s):  
René Alfredo Cano-Hidalgo ◽  
Tatiana Urrea-Victoria
Keyword(s):  
Optical Coherence Tomography ◽  
Choroidal Thickness ◽  
Invasive Technique ◽  
Optical Coherence ◽  
Horizontal Section ◽  
Swept Source ◽  
Non Invasive ◽  
The Mean ◽  
Foveal Center ◽  
Fellow Eyes

Objective The objective of the study was to describe and evaluate the subfoveal choroidal thickness (SFCT) in the fellow eyes of patients with central serous chorioretinopathy (CSC) using swept source optical coherence tomography (SS-OCT). Methods This was a transversal, retrospective, and observational study. The SFCT was measured in patients with unilateral CSC using SS-OCT. The choroidal thickness in symptomatic and fellow eyes was measured using the attached measuring software in SS-OCT. The SFCT dimension was obtained from the horizontal section under the foveal center from the OCT data and these data were analyzed. Results The mean age of subjects undergoing imaging SS-OCT was 44.23 years old (standard deviation, 11.57). 30 out of 60 patients (63.3%) were men, and 20 (33.3%) patients had acute clinical disease. The median choroidal thicknesses of the affected eyes were greater than those of the unaffected fellow eyes (P = 0.06). The choroidal thickness measured in 120 eyes of (60 patients) was 421 µm (interquartile range 352–490), which was greater than the choroidal thickness reported in normal eyes. Conclusions The measuring of the choroidal thickness using SS-OCT is useful as a non-invasive technique to evaluate the subclinical choroidal abnormalities in CSC.

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