Michael Chaglasian

Dr. Michael Chaglasian

orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 May 2018 in Clinical Ophthalmology
Verified
Journal Article
Open access
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MCMichael Chaglasian
Michael Chaglasian
MFMurray Fingeret
Murray Fingeret
Pinakin DaveyPinakin Davey
Pinakin Davey
WHWei-Chieh Huang
Wei-Chieh Huang
DLDanny Leung
Danny Leung
CRCharles Reisman
Charles Reisman
The development of a reference database with the Topcon 3D OCT-1 Maestro Michael Chaglasian,1 Murray Fingeret,2 Pinakin Gunvant Davey,3 Wei-Chieh Huang,4 Danny Leung,4 Edmund Ng,5 Charles A Reisman4 1Illinois Eye Institute, Illinois College of Optometry, Chicago, IL, USA; 2Department of Veterans Affairs, New York Harbor Health Care System, Brooklyn, NY, USA; 3School of Optometry, Western University of Health Sciences, Pomona, CA, USA; 4Topcon Healthcare Solutions Research and Development, Oakland, NJ, USA; 5Edmund Ng Consulting, LLC, Seattle, WA, USA Importance: The paper presents the range for measurements taken with a new spectral domain optical coherence tomography (OCT) device to establish a reference database for discrimination purposes. Objective: To report the range of thickness values for the new Topcon Maestro 3D OCT device with 2 scan size settings: the 12×9 mm wide field and 6×6 mm scans. Design: Prospective, multicenter cohort study conducted at 7 clinical sites across the USA. Setting: Primary eyecare clinics within academic, hospital, and private practice locations. Participants: Healthy volunteers; all enrolled participants underwent a complete ophthalmological examination to confirm healthy ocular status prior to being enrolled in the study. Main outcome measure: Average and 1st, 5th, 95th, and 99th percentile ranges for OCT parameters Early Treatment Diabetic Retinopathy Study macula full retinal thickness, ganglion cell + inner plexiform layer thickness (GCL + IPL), ganglion cell complex (GCC) thickness, circumpapillary retinal nerve fiber layer (cpRNFL) thickness. Results: Three hundred and ninety-nine eyes of 399 subjects were included in the analysis. Mean (SD) age was 46.3 (16.3) years (range 18–88 years). Forty-three percent of the subjects were male. Mean (SD) measurements (in μm) for the 12×9 mm wide scan were as follows: foveal thickness=237.079 (20.899), GCL + IPL=71.363 (5.924), GCC=105.949 (8.533), cpRNFL=104.720 (11.829); measurements for the 6×6 mm scans were as follows: foveal thickness=234.000 (20.657), GCL + IPL=71.726 (5.880), GCC=106.698 (9.094), cpRNFL=104.036 (11.341). Conclusion: The overall normal thickness values reported with Topcon 3D OCT-1 Maestro were like those studies with OCT from different manufactures. The reference limits at the 1st, 5th, 95th, and 99th percentile points establish the thresholds for the quantitative comparison of the cpRNFL and the macula in the human retina to a database of known healthy subjects. Keywords: spectral domain optical coherence tomography, normal eyes, 3D OCT-1 Maestro, macular measurements, circumpapillary retinal nerve fiber layer, optic disc

8 November 2024 in Journal of Clinical Medicine
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Journal Article
Open access
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MCMichael Chaglasian
Michael Chaglasian
TNTakashi Nishida
Takashi Nishida
SMSasan Moghimi
Sasan Moghimi
ASAshley Speilburg
Ashley Speilburg
MDMary Durbin
Mary Durbin
RWRobert N Weinreb
Robert N Weinreb
Background/Objectives: This study aims to develop and validate a Glaucoma Health Score (GHS) that incorporates multiple individual glaucoma risk factors to enhance glaucoma detection in screening environments. Methods: The GHS was developed using a retrospective dataset from two clinical sites, including both eyes of glaucoma patients and controls. The model incorporated age, central corneal thickness, intraocular pressure, pattern standard deviation from a visual field threshold 24-2 test, and two parameters from an optical coherence tomography (OCT) test: the average circumpapillary retinal nerve fiber layer thickness and the minimum thickness of the six sectors of the macular ganglion cell plus the inner plexiform layer. The GHS was then validated in two independent datasets: one from primary care sites using Maestro OCT data (test dataset 1) and another from an academic center using DRI OCT Triton (test dataset 2). Results: Both eyes of 51 glaucoma patients and 67 controls were included in the development dataset. Setting the GHS cutoff at 75 points out of 100, test dataset 1, which comprised 41 subjects with glaucoma and 41 healthy controls, achieved an area under the receiver operating characteristic curve (AUROC) of 0.98, with a sensitivity of 71% and specificity of 98%; test dataset 2, which included 53 patients with glaucoma and 53 healthy controls, resulted in an AUROC of 0.95, with a sensitivity of 75% and specificity of 96%. A decision curve analysis across all datasets demonstrated a higher net benefit for the GHS model compared to individual OCT parameters. Conclusions: The GHS offers a feasible, standardized approach for early detection of glaucoma, providing strong specificity and acceptable sensitivity, with clear decision-making benefits in screening settings.

15 April 2025 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
MCMichael Chaglasian
Michael Chaglasian
HHHuiyuan Hou
Huiyuan Hou
MTMayra Tafreshi
Mayra Tafreshi
MDMary Durbin
Mary Durbin
ETEce Turhal
Ece Turhal
AHAlex Huang
Alex Huang
Background/Objectives: This study aimed to evaluate the clinical interchangeability of intraocular pressure (IOP) measurements between a non-contact tonometer (NCT), the TRK-3 OMNIA, and Goldmann applanation tonometry (GAT) and to assess the repeatability of TRK-3 measurements. Methods: This prospective, multicenter study included 120 subjects stratified into three IOP groups based on GAT measurements: low IOP (7–16 mmHg), intermediate IOP (>16 to <23 mmHg), and high IOP (≥23 mmHg). The study eye was randomly selected from each subject. IOP was measured using both TRK-3 OMNIA and GAT following a standardized protocol. Agreement between the two methods was evaluated using Bland–Altman analysis, 95% limits of agreement (LoA), and equivalence testing via the two one-sided test (TOST) approach with a predefined ±5 mmHg margin. Linear regression analysis was performed to characterize the relationship between TRK-3 and GAT measurements. The repeatability of TRK-3 measurements was assessed using the intraclass correlation coefficient (ICC), repeatability limit, and coefficient of variation (CV). Results: Across all subjects, the mean difference between TRK-3 OMNIA and GAT IOP measurements was −0.2 mmHg. TRK-3 OMNIA overestimated IOP in the low IOP group (mean difference: 2.1 mmHg, LoA: −1.2 to 5.4 mmHg) and underestimated in the high IOP group (mean difference: −2.4 mmHg, LoA: −5.9 to 1.1 mmHg), while agreement was highest in the intermediate IOP group (−0.2 mmHg, LoA: −2.9 to 2.5 mmHg). Despite the systematic trend, equivalence testing confirmed statistical equivalence across all groups, with 90% confidence intervals (CI) of 1.7 to 2.5 mmHg (low IOP group), −0.6 to 0.2 mmHg (intermediate IOP group), and −2.9 to −2.0 mmHg (high IOP group). Linear regression analysis found a strong correlation (r = 0.92) between TRK-3 and GAT. The TRK-3 OMNIA demonstrated good repeatability, with an ICC of 0.94, a repeatability limit of 3.12 mmHg, and a CV of 5.65%. The repeatability limits were 2.22 mmHg, 2.60 mmHg, and 4.19 mmHg in the low, intermediate, and high IOP groups, respectively. Conclusions: TRK-3 OMNIA and GAT measurements showed strong agreement, statistical equivalence, and a high correlation, supporting their clinical interchangeability. TRK-3 also demonstrated high repeatability. These findings indicate that this automated non-contact tonometer provides reliable and repeatable IOP measurements, supporting its integration into routine clinical workflows.

19 December 2024 in Clinical and Experimental Optometry
Verified
Journal Article
Closed access
PSPatricia Salazar
Patricia Salazar
ASAshley Speilburg
Ashley Speilburg
ARAnne Rozwat
Anne Rozwat
MCMichael Chaglasian
Michael Chaglasian
DRDaniel Roberts
Daniel Roberts
MSMichael Sinai
Michael Sinai
Clinical evaluation of the optic nerve using 3-D stereo disc photographs is considered the gold standard for estimating vertical cup-to-disc ratios. Ultra-widefield retinal imaging has gained increasing popularity to document and screen the health of the retina and optic nerve. Glaucoma is often first identified or suspected based on initial optic nerve assessment. Despite technological advancements in imaging, stereo disc photography remains the gold standard of optic nerve assessment. This study compared vertical cup-to-disc ratio (VCDR) estimations using ultra-widefield scanning laser ophthalmoscopy images with estimations using paired stereo disc images. Thirty-five healthy and 35 glaucomatous eyes were imaged using Zeiss VISUCAM® PRO NM and Optos Monaco® (optomap®) [Registered in U.S. Patent and Trademark Office] devices. Four experienced clinicians assessed each image in a masked fashion and graded the VCDR. Stereo viewers and review software tools were used to determine VCDRs. Bland-Altman plots and regression/correlation analyses were used to check VCDR agreement. Bland-Altman analyses showed low mean differences between devices with VCDR estimation for each grader (-0.03, +0.01, -0.02, and +0.03). Difference vs. means plots suggest stable differences across the range of measurement. VCDR estimations were comparable using optomap® images and VISUCAM® PRO NM stereo optic disc images.