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The Glaucoma Module is a software application intended for the management, display and analysis of visual field and optical coherence tomography data. It is intended as an aid to the detection and management of visual field defects and progression of visual field loss.

The Glaucoma Module works as an optional module, integrated into the Harmony user interface, and interfacing to Harmony to access the relevant data and information. Harmony is a comprehensive software platform intended for use in importing, processing, measurement, analysis and storage of clinical images and videos of the eye, as well as for management of patient data, diagnostic data, clinical information, reports from ophthalmic diagnostic instruments through either a direct connection with the instruments or through computerized networks. Harmony was most recently cleared by FDA in K182376.

The Glaucoma Module is a fully interactive multi-modality software for clinicians to assess, diagnose and manage patients who are glaucoma suspects or have been diagnosed with glaucoma. The Glaucoma Module is an aid to detection and management of visual field and OCT data.

The Glaucoma Module displays key information for diagnosis and management using a wellorganized interface.

Glaucoma Module is integrated into the Harmony user interface that utilizes both OCT exam and Visual Field data in an interactive manner. It employs two main sections, the Hood Dashboard screen used to determine glaucoma suspects and the Glaucoma Trend screen which can be used to observe patient data over a larger period of time.

The Glaucoma Module does not include predictive interpretations of the correlation of structural and functional measures, two measures that are understood to be independent of each other.

The Glaucoma Module will work with the following medical devices:

• Topcon's Maestro. Maestro 2, and Triton Optical Coherence Tomography devices .
• Zeiss' Visual Field instruments HFA3 and HFA Iii
• Visual Field data from other manufacturers. (e.g. Oculus EasyField) through DICOM ● OPV data format.

Here's a breakdown of the requested information based on the provided text:

Key Takeaway: The provided 510(k) summary for the Topcon Healthcare Solutions Glaucoma Module states that no performance data was required or provided for its clearance. This means there is no study described in this document that proves the device meets specific acceptance criteria related to its clinical performance. Instead, the clearance primarily relies on demonstrating substantial equivalence to a predicate device through similar intended use and technological characteristics, as well as software validation and verification.

1. Table of Acceptance Criteria and Reported Device Performance

Note: The document explicitly states, "No performance data was required or provided. Software validation and verification demonstrate that the Glaucoma Module performs as intended and meets its' specifications." Therefore, the "acceptance criteria" here are primarily functional and technical requirements met through software testing and comparison to a predicate, not clinical performance metrics like sensitivity, specificity, or accuracy.

2. Sample Size Used for the Test Set and Data Provenance

• Sample Size: Not applicable. No clinical performance testing against a specific test set is mentioned.
• Data Provenance: Not applicable. No clinical performance testing data is provided.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications

• Not applicable. No clinical performance testing against a ground truth is mentioned.

4. Adjudication Method for the Test Set

• Not applicable. No clinical performance testing with adjudication is mentioned.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

• No. An MRMC comparative effectiveness study was not done or reported.

6. If a Standalone (i.e. algorithm only, without human-in-the-loop performance) was done

• No. A standalone performance study was not done or reported. The device is described as a software application for clinicians to aid in assessment, diagnosis, and management, implying a human-in-the-loop context. However, no performance data (standalone or otherwise) is presented.

7. The Type of Ground Truth Used

• Not applicable. No ground truth for clinical performance evaluation is mentioned.

8. The Sample Size for the Training Set

• Not applicable. The document does not describe any machine learning or AI algorithm development that would involve a training set. The device is a "software application intended for the management, display and analysis..." and not an AI/ML diagnostic tool requiring such a set.

9. How the Ground Truth for the Training Set was Established

• Not applicable. As no training set is mentioned, no ground truth for it was established.

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The CIRRUS™ HD-OCT is a non-contact, high resolution tomographic and biomicroscopic imaging device intended for in-vivo viewing, axial cross-sectional, and three-dimensional imaging of anterior ocular structures. The device is indicated for visualizing anterior and posterior ocular structures, including cornea, retina, retinal nerve fiber layer, ganglion cell plus inner plexiform layer, macula, and optic nerve head. The CIRRUS normative databases are quantitative tools indicated for the comparison of retinal nerve fiber layer thickness, ganglion cell plus inner plexiform layer thickness, and optic nerve head measurements to a database of normal subjects. The CIRRUS OCT angiography is indicated as an aid in the visualization of vascular structures of the retina and choroid. The CIRRUS HD-OCT is indicated as a diagnostic device to aid in the detection and management of ocular diseases including, but not limited to, macular holes, cystoid macular edema, diabetic retinopathy, age-related macular degeneration, and glaucoma.

The CIRRUSTM HD-OCT is a computerized instrument that acquires and analyzes crosssectional tomograms of anterior and posterior ocular structures (including cornea, retina, retinal nerve fiber layer, macula, and optic disc). It employs non-invasive, non-contact, low-coherence interferometry to obtain these high-resolution images. Using this noninvasive optical technique. CIRRUS HD-OCT produces high-resolution cross-sectional tomograms of the eye without contacting the eye. It also produces images of the retina and layers of the retina from an en face perspective (i.e., as if looking directly in the eye).

The CIRRUS HD-OCT is offered in four models, Model 4000, 400, 5000 and 500. In the CIRRUS HD-OCT Models 4000 and 5000, the fundus camera is a line scanning ophthalmoscope. The CIRRUS HD-OCT Models 400 and 500 are similar to the Models 4000 and 5000 except that they provide the fundus image using the OCT scanner only.

The acquired imaging data can be analyzed to provide thickness and area measurements of regions of interest to the clinician. The system uses acquired data to determine the fovea location or the optic disc location. Measurements can then be oriented using the fovea and/or optic disc locations. The patient's results can be compared to subjects without disease for measurements of RNFL thickness, neuro-retinal rim area, average and vertical cup-to-disc area ratio, cup volume, macular thickness and ganglion cell plus inner plexiform layer thickness.

In addition to macular and optic disc cube scans, the CIRRUS HD-OCT also offers scans for OCT angiography imaging, a non-invasive approach with depth sectioning capability to visualize microvascular structures of the eye.

Anterior segment scans enable analysis of the anterior segment including Anterior Chamber Depth. Angle-to-Angle and automated measurement of the thickness of the cornea with the Pachymetry scan.

Here's an analysis of the provided text, outlining the acceptance criteria and the study details for the Carl Zeiss Meditec Inc. Cirrus HD-OCT with Software Version 8.

Acceptance Criteria and Device Performance:

The document primarily focuses on demonstrating repeatability and reproducibility of measurements, and comparability between the new device (CIRRUS HD-OCT with Software Version 8, specifically Models 4000 and 5000) and the predicate device (Visante OCT). Specific acceptance criteria are not explicitly stated as numerical targets in quantifiable terms for all parameters. Instead, the study aims to show that the new device's measurements are consistent and comparable to the predicate device. The tables report the demonstrated performance rather than predefined acceptance criteria.

Table of Acceptance Criteria and Reported Device Performance (Inferred from the study's objective to demonstrate comparability, repeatability, and reproducibility):

Study Details:

1. Sample sizes used for the test set and data provenance:

   • Anterior Chamber and Pachymetry Scans:
     • Normal Cornea group: 46 subjects (Group 1)
     • Post-LASIK group: 40 subjects (Group 2)
     • Corneal Pathology group: 45 subjects (Group 3)
     • Age Range (all groups): 25 to 69 years.
     • Data Provenance: Not explicitly stated (e.g., country of origin). The study is described as a "non-significant risk clinical study," implying prospective data collection in a clinical setting.
   • Angle Study:
     • Angle Study: 27 subjects, ranging from 43 to 77 years (mean 62 years).
     • Specific eye counts per measurement type:
       • 26 eyes for Wide Angle-to-Angle scan
       • 27 eyes for HD Angle scan
     • Data Provenance: Not explicitly stated (e.g., country of origin). Described as a "non-significant risk clinical study," implying prospective data collection.
   • OCT Angiography: Series of case studies. No specific sample size is provided beyond "case studies."

2. Number of experts used to establish the ground truth for the test set and their qualifications:

   • Anterior Chamber and Pachymetry Scans: No external experts were used for "ground truth" in the sense of an adjudicated diagnosis. The study focused on comparing measurements between devices and assessing repeatability/reproducibility. The predicate device (Visante OCT) served as the reference for comparability. One operator acquired data on the Visante OCT. Three operators acquired data on the CIRRUS HD-OCT devices.
   • Angle Study: The study focused on device measurement comparison, repeatability, and reproducibility. One operator acquired data on the Visante OCT. Three operators acquired data on the CIRRUS HD-OCT devices. The study population had a variety of angle configurations (Grade II to Grade IV) as assessed by gonioscopy using the Shaffer method, but the gonioscopy results themselves were not used as a direct "ground truth" for individual measurement values from the OCT devices.
   • OCT Angiography: The "findings demonstrate that the CIRRUS OCT Angiography... can give non-invasive three-dimensional information regarding retinal microvasculature." This was compared with "fluorescein angiography images." The number and qualifications of experts interpreting either the OCTA or fluorescein angiography images for these case studies are not specified in the provided text.

3. Adjudication method for the test set:

   • Anterior Chamber and Pachymetry Scans: Not applicable for establishing ground truth, as the study focused on device measurement comparison and repeatability/reproducibility across devices and operators. Measurements were generated by "manual placement of software tools."
   • Angle Study: Similar to the above, not applicable for establishing "ground truth" through adjudication. Measurements were generated by "manual placement of software tools (Angle tool; TISA tool)" by the operators who acquired the data.
   • OCT Angiography: Not specified.

4. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:

   • No, a multi-reader multi-case (MRMC) comparative effectiveness study with human readers and AI assistance was not explicitly reported or performed in the provided text. The study primarily focused on the device's technical performance (repeatability, reproducibility, and agreement with a predicate device) rather than its impact on human reader diagnostic accuracy with or without AI. The device itself (CIRRUS HD-OCT with Software Version 8) is an imaging and measurement device, not explicitly an "AI" diagnostic tool in the context of human-in-the-loop performance measurement.

5. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:

   • Yes, in a sense, the primary studies for Anterior Chamber, Pachymetry, and Angle measurements assessed the standalone performance of the device's measurement algorithms by evaluating their repeatability, reproducibility, and agreement with predicate device measurements. These measurements are generated by the device's software (e.g., "manual placement of software tools" by an operator, but the calculation is still algorithmic). The OCT Angiography section also mentions the device's ability to provide information on microvasculature without human "in-the-loop" interpretation for the basic image generation. However, it's not described as an "AI algorithm" in the common sense of diagnosing from images.

6. The type of ground truth used:

   • Anterior Chamber, Pachymetry, and Angle Studies: The "ground truth" was effectively the measurements obtained from the predicate device (Visante OCT). The purpose was to show substantial equivalence and comparability, not to determine diagnostic accuracy against an independent, gold-standard clinical pathology or outcome.
   • OCT Angiography: Comparisons were made with fluorescein angiography images. Fluorescein angiography is a clinical gold standard for visualizing retinal and choroidal vasculature.

7. The sample size for the training set:

   • The document does not provide information on the training set size. The studies described are validation studies for the device's technical performance and comparability to a predicate. The device incorporates "proprietary algorithms" and "normative databases," which would have been developed using some form of training data, but details about this training data are not included in the provided 510(k) summary.

8. How the ground truth for the training set was established:

   • Not described in the provided text. As mentioned above, the 510(k) summary focuses on the validation studies, not the development or training of any underlying algorithms or normative databases. The "normative databases" would inherently rely on data from "normal subjects," but the specifics of their ground truth establishment are not given.

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The CIRRUS photo is a non-contact, high resolution tomographic and biomicroscopic imaging device that incorporates a digital camera which is suitable for photographing, displaying and storing the data of the retina and surrounding parts of the eye to be examined under mydriatic and non-mydriatic conditions.

These photographs support the diagnosis and subsequent observation of eye diseases which can be visually monitored and photographically documented. The CIRRUS photo is indicated for in vivo viewing, axial cross sectional, and three-dimensional imaging and measurement of posterior ocular structures, including retinal nerve fiber layer, macula and optic disc as well as imaging of anterior ocular structures and measurement of central corneal thickness.

It also includes a Retinal Nerve Fiber Layer (RNFL), Optic Nerve Head (ONH), and Macular Normative Database which are quantitative tools for the comparison of retinal nerve fiber layer, optic nerve head, and the macula in the human retina to a database of known normal subjects. It is intended for use as a diagnostic device to aid in the detection and management of ocular diseases including, but not limited to, macular holes, cystoid macular edema, diabetic retinopathy, age-related macular degeneration, and glaucoma.

The CIRRUS photo is a computerized optical instrument that combines the diagnostic and imaging capabilities of the Carl Zeiss Meditec VISUCAM PRO NM Digital Camera and the Carl Zeiss Meditec Cirrus HD-OCT Optical Coherence Tomographer Model 4000. The CIRRUS photo was developed to provide both subjective and objective imaging, and to optimize space by combining fundus photography and spectral domain optical coherence tomography, allowing the anterior or posterior segments of the eye to be viewed and photographically documented with the pupil in a non-mydriatic state, within the same instrument. To optimize the workflow, the system applies the same optical beam delivery system for imaging and scanning.

The CIRRUS photo consists of a Fundus Camera Main Unit and a spectral domain optical coherence tomographer (SD-OCT) Module, both of which are installed on a single instrument table. The CIRRUS photo is operated via computer mouse, keyboard and joystick as part of the base of the main unit and an external monitor is mounted on top of the instrument table.

The CIRRUS photo is offered in two models. Model 600 and Model 800. Fundus auto fluorescence is available on both the Model 600 and 800; the Model 800 also offers fluorescein angiography and indocyanine green angiography (ICGA).

CIRRUS photo data can be analyzed using the same Cirrus HD-OCT algorithms and normative database cleared under K111157 (Cirrus HD-OCT software version 6.0), including Advanced Retinal Pigment Epithelium (RPE) Analysis, Guided Progression Analysis (GPA) for Optic Nerve Head (ONH) parameters, and Ganglion Cell Analysis, and the Ganglion Cell Normative Database. As these algorithms and database reside separately on the Cirrus HD-OCT version 6.0 software, the analyses of the CIRRUS photo data are carried out using an external Cirrus Review station.

The CIRRUS photo Models 600 and 800 underwent several studies to demonstrate substantial equivalence to predicate devices and to support expanded indications for use. Key studies focused on evaluating the repeatability, reproducibility, and comparability of measurements between the CIRRUS photo and the Cirrus HD-OCT Model 4000 for Central Corneal Thickness (CCT), RPE illumination/elevation, and Ganglion Cell Analysis (GCA) parameters.

The primary method for establishing acceptance criteria and demonstrating performance was through equivalence studies, comparing the new device against a predicate device (Cirrus HD-OCT Model 4000) for key measurement parameters. The acceptance criteria generally involved demonstrating that the mean difference between measurements from the CIRRUS photo and the predicate device was close to zero, with narrow 95% Confidence Intervals and Limits of Agreement, and that repeatability and reproducibility standard deviations were small.

Here's a breakdown of the acceptance criteria and study details:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Implicit / Demonstrated Equivalence to Predicate, and good Repeatability/Reproducibility)

• Phase I: -0.89 µm (95% CI: -2.85, 1.06)
• Phase II: 1.20 µm (95% CI: 0.22, 2.19)
  Repeatability (SD): 4.49 µm (COV: 0.8%)
  Reproducibility (SD): 5.216 µm (COV: 0.96%)
  Performance meets implicit criteria for agreement and precision. |
  | Area of Sub-RPE Illumination (mm²) | Mean difference between devices close to 0; 95% CI of mean difference crossing 0 or very small; 95% Limits of Agreement clinically acceptable. Good repeatability and reproducibility (small SD and COV). | Mean Difference (CIRRUS photo - Cirrus HD-OCT):
• 200x200 Scan: -0.0108 mm² (95% CI: -0.1632, 0.1416)
• 512x128 Scan: -0.0314 mm² (95% CI: -0.1742, 0.1115)
  Repeatability (SD): 0.1099 mm² (200x200), 0.1329 mm² (512x128)
  Reproducibility (SD): 0.1774 mm² (200x200), 0.2442 mm² (512x128)
  Performance meets implicit criteria for agreement and precision. |
  | Closest Distance to Fovea (mm) | Mean difference between devices close to 0; 95% CI of mean difference crossing 0 or very small; 95% Limits of Agreement clinically acceptable. Good repeatability and reproducibility (small SD and COV). | Mean Difference (CIRRUS photo - Cirrus HD-OCT):
• 200x200 Scan: 0.01 mm (95% CI: -0.01, 0.02)
• 512x128 Scan: 0.02 mm (95% CI: -0.00, 0.03)
  Repeatability (SD): 0.0343 mm (200x200), 0.0397 mm (512x128)
  Reproducibility (SD): 0.0447 mm (200x200), 0.0571 mm (512x128)
  Performance meets implicit criteria for agreement and precision. |
  | Area of RPE Elevation (mm²) | Mean difference between devices close to 0; 95% CI of mean difference crossing 0 or very small; 95% Limits of Agreement clinically acceptable. Good repeatability and reproducibility (small SD and COV). | Mean Difference (CIRRUS photo - Cirrus HD-OCT, 3mm Circle):
• 200x200 Scan: -0.040 mm² (95% CI: -0.098, 0.018)
• 512x128 Scan: -0.004 mm² (95% CI: -0.074, 0.066)
  Reproducibility COV%: 8.30% (200x200, 3mm Circle), 8.89% (512x128, 3mm Circle)
  Performance meets implicit criteria for agreement and precision. |
  | Volume of RPE Elevation (mm³) | Mean difference between devices close to 0; 95% CI of mean difference crossing 0 or very small; 95% Limits of Agreement clinically acceptable. Good repeatability and reproducibility (small SD and COV). | Mean Difference (CIRRUS photo - Cirrus HD-OCT, 3mm Circle):
• 200x200 Scan: -0.0024 mm³ (95% CI: -0.0050, 0.0002)
• 512x128 Scan: 0.0002 mm³ (95% CI: -0.0029, 0.0034)
  Reproducibility COV%: 8.45% (200x200, 3mm Circle), 9.07% (512x128, 3mm Circle)
  Performance meets implicit criteria for agreement and precision. |
  | Ganglion Cell Analysis (GCA) Parameters (e.g., Average GCL+IPL Thickness) | Mean difference between devices close to 0; 95% CI of mean difference crossing 0 or very small; 95% Limits of Agreement clinically acceptable. Good repeatability and reproducibility (small SD and COV). | Mean Difference (CIRRUS photo - Cirrus HD-OCT, Average Thickness):
• Normal Eyes: -0.3 µm (95% CI: -0.5, -0.2)
• Diseased Eyes: -0.3 µm (95% CI: -0.5, -0.2)
  Reproducibility COV% (Average Thickness): 0.97% (Normal), 0.98% (Diseased)
  Performance meets implicit criteria for agreement and precision across numerous GCA parameters. |
  | GCA Normative Database Transference | CIRRUS photo measurements should be comparable to Cirrus HD-OCT to allow adjustment and use of the established normative database. | Regression analysis was used to adjust the Cirrus HD-OCT GCA Normative Database for use with CIRRUS photo, creating an "adjusted CIRRUS photo Normative Database." This indicates successful transference and adjustment. |

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

The studies were prospective. The country of origin is not explicitly stated, but the company is based in Germany with a US contact, suggesting a likely multi-site international or US-based study given the English language requirement in one study.

Test Set Sample Sizes:

• Central Corneal Thickness (CCT) Study:
  • Phase I (inter-device variability): 29 subjects enrolled, 28 included in analysis.
  • Phase II (inter-operator variability): 23 subjects enrolled and qualified for analysis.
• Area of Increased Illumination under RPE (dry AMD with GA) Study: 21 enrolled subjects, with at least one eye qualifying. Mean age 79.8 years.
• Elevated RPE (dry AMD with drusen) Study: 31 enrolled subjects, with at least one eye qualifying. Mean age 80.1 years.
• Ganglion Cell Analysis (GCA) Normal Eyes Study:
  • Phase I (inter-operator variability): 30 subjects.
  • Phase II (inter-device variability): 33 subjects. Combined mean age 43.5 years.
• Ganglion Cell Analysis (GCA) Diseased Eyes (Glaucoma) Study: 77 subjects enrolled, 68 included in analysis (37 mild, 16 moderate, 13 severe, 2 end-stage glaucoma). Mean age 67.4 years.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

The studies described are primarily comparability, repeatability, and reproducibility studies, not diagnostic accuracy studies against a definitive ground truth established by experts in the traditional sense. The "ground truth" here is the measurement obtained by the predicate device (Cirrus HD-OCT Model 4000) and the consistency of measurements within and between devices/operators.

For the RPE analyses (increased illumination and elevated RPE), operators reviewed and manually edited the automated segmentation algorithm output when necessary, consistent with instructions. This suggests that the operators (who were administering the tests) were also implicitly acting as "experts" for reviewing and refining the data derived by the algorithm, effectively enhancing the quality of the algorithmic output, but not establishing a separate, independent ground truth. The number and qualifications of these "operators" are not explicitly stated as "experts" in the clinical evaluation sense, but rather as trained personnel for device operation and data review.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

There was no explicit independent adjudication method (like 2+1 or 3+1) described for establishing ground truth from multiple experts. For the RPE studies, the "ground truth" was derived from the automated segmentation algorithms, with manual editing by the operating personnel, but without a formal multi-reader consensus process indicated. The focus was on comparing measurements between devices and assessing measurement consistency.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

No MRMC comparative effectiveness study was conducted or described in the provided text. The studies focused on the performance of the device's measurement algorithms themselves (standalone performance and comparability to a predicate device), not on how human readers' diagnostic accuracy is improved with or without AI assistance from this specific device.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done**

Yes, standalone performance was implicitly evaluated through the comparability, repeatability, and reproducibility studies. The device measures various parameters (CCT, RPE illumination/elevation, GCA thickness values) using its inherent algorithms. The comparison against the predicate device (Cirrus HD-OCT Model 4000) essentially evaluates the standalone measurement capability of the CIRRUS photo's algorithms against an established standard. While human operators are involved in operating the device and in some cases, reviewing and correcting automated segmentations (especially for RPE analyses), the core "performance" being evaluated is the accuracy and precision of the numerical measurements generated by the device's algorithms.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

The "ground truth" in these studies was primarily comparative to a predicate device (Cirrus HD-OCT Model 4000) and statistical measures of repeatability and reproducibility. For the advanced RPE analysis, the ground truth for the segmentation of increased illumination areas and RPE elevations was the output of the device's automated segmentation algorithm, refined by manual editing from the operators. There is no mention of pathology, expert consensus (beyond operator review), or long-term outcomes data as a definitive ground truth for individual measurements.

8. The sample size for the training set

The training set information is only explicitly provided for the Ganglion Cell Normative Database, which was adapted for the CIRRUS photo.

• GCA Normative Database: Derived from an additional analysis of the Cirrus HD-OCT Macular Thickness normative database, which included 282 subjects. These subjects were aged 19-84 years, considered representative of a normal population, and data was collected from seven sites.

For the other advanced algorithms (e.g., Advanced RPE Analysis, GPA), the document states they "reside separately on the Cirrus HD-OCT version 6.0 software" and are carried out using an external Cirrus Review station. This implies these algorithms were developed and likely trained prior to this submission, on data associated with the predicate Cirrus HD-OCT system (K111157), but specific training set sizes for these individual algorithms are not provided within this document.

9. How the ground truth for the training set was established

For the Ganglion Cell Normative Database (and by extension the Macular Thickness normative database):

• The ground truth was established by identifying subjects deemed "representative of a normal population."
• Scans were acquired from these normal subjects.
• Segmentation algorithms were applied to identify the thickness of specific layers (e.g., combined ganglion cell plus inner plexiform layers for GCA).
• These measurements from normal subjects then formed the reference values for the normative database, which is age-corrected. This database essentially defines "normal" based on statistical distribution from this large sample.

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