(385 days)
The LENSTAR LS 900 is a non-invasive, non-contact OLCR (Optical Low Coherence Reflectometry) Biometer used for obtaining ocular measurements and performing calculations to assist in the determination of the appropriate power and type of IOL (intraocular lens) for implantation after removal of the natural crystalline lens following cataract removal. The LENSTAR LS 900 measures:
- Axial eye length
- Corneal thickness
- Anterior chamber depth
- Aqueous depth
- Lens thickness
- Radii of curvature of flat and steep meridian
- Axis of the flat meridian
- White to white distance
- Pupil diameter
The LENSTAR LS 900 is a non-invasive, non-contact system for measuring the parameters of the human eye required to determine the appropriate IOL for implantation and to calculate the optimal power of the IOL. The LENSTAR LS 900 measures: axial eye length, corneal thickness, anterior chamber depth, lens thickness, radii of curvature of flat and steep meridian, axis of flat or step meridian, white to white distance and pupil diameter.
Acceptance Criteria and Device Performance for LENSTAR LS 900
This report details the acceptance criteria and the study conducted to demonstrate the substantial equivalence of the Haag-Streit LENSTAR LS 900 to predicate devices.
1. Table of Acceptance Criteria and Reported Device Performance
The provided document doesn't explicitly state quantitative acceptance criteria for the LENSTAR LS 900. Instead, it focuses on demonstrating "substantive equivalence" to existing, legally marketed predicate devices through a comparison of measurement data. The "acceptance criteria" can therefore be inferred as demonstrating a high degree of statistical correlation or agreement in measurements between the LENSTAR LS 900 and the predicate devices.
| Measurement Parameter | Acceptance Criteria (Inferred from Study Design) | Reported Device Performance (Summary from Clinical Study) |
|---|---|---|
| Axial eye length | Data demonstrates substantial equivalence to predicate devices (IOLMaster, OLCR, Accusonic A-Scan). | Analysis of clinical data substantiates equivalence to all predicates. |
| Corneal thickness | Data demonstrates substantial equivalence to predicate devices (OLCR, Accusonic A-Scan). | Analysis of clinical data substantiates equivalence to all predicates. |
| Anterior chamber depth | Data demonstrates substantial equivalence to predicate devices (IOLMaster, OLCR). | Analysis of clinical data substantiates equivalence to all predicates. |
| Lens thickness | Data demonstrates substantial equivalence to predicate devices (IOLMaster, OLCR). | Analysis of clinical data substantiates equivalence to all predicates. |
| Radii of curvature (flat/steep) | Data demonstrates substantial equivalence to predicate devices (IOLMaster, Keratron). | Analysis of clinical data substantiates equivalence to all predicates. |
| Axis of flat meridian | Data demonstrates substantial equivalence to predicate devices (IOLMaster, Keratron). | Analysis of clinical data substantiates equivalence to all predicates. |
| White to white distance | Data demonstrates substantial equivalence to predicate devices (IOLMaster). | Analysis of clinical data substantiates equivalence to all predicates. |
| Pupil diameter | Data demonstrates substantial equivalence to predicate devices (IOLMaster). | Analysis of clinical data substantiates equivalence to all predicates. |
| Aqueous depth | Data demonstrates substantial equivalence to predicate devices. (No specific predicate mentioned, but included in the list of measured parameters.) | Analysis of clinical data substantiates equivalence to all predicates. |
| IOL Power Calculation Aid | Functionality in assisting IOL power determination demonstrates substantial equivalence to predicate devices that provide similar assistance (e.g., IOLMaster). | The device performs calculations to assist in IOL determination, similar to predicate devices, and its measurements contribute to this equivalence. |
2. Sample Size and Data Provenance
- Sample Size for Test Set: The document does not specify the exact sample size for the test set of patients used in the clinical studies. It only states that "Two prospective, non-randomized, single site comparison studies were performed."
- Data Provenance: The studies were conducted in Berne, Switzerland. The data is prospective, as indicated by "Two prospective... studies were performed."
3. Number of Experts and Qualifications for Ground Truth
The document does not specify the number of experts used to establish ground truth or their qualifications. The study design primarily focuses on comparing measurements obtained by the LENSTAR LS 900 with those from established predicate devices. The "ground truth" for the test set is effectively derived from the measurements produced by these predicate devices.
4. Adjudication Method for the Test Set
The document does not describe any specific adjudication method (e.g., 2+1, 3+1) for the test set. The clinical summary indicates "comparison studies" were performed, meaning the data from the LENSTAR LS 900 was directly compared to the measurements from the predicate devices.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, an MRMC comparative effectiveness study was not done. The studies described are focused on the equivalence of device measurements, not on the improvement of human reader performance with AI assistance. The LENSTAR LS 900 is a measurement device, not an AI-assisted diagnostic tool for human readers in the typical sense of an MRMC study.
6. Standalone Performance Study (Algorithm Only)
Yes, a standalone performance study was done implicitly. The clinical studies evaluated the LENSTAR LS 900's ability to measure various ocular parameters independently and then compared these measurements to those obtained by predicate devices. This constitutes a standalone performance evaluation in terms of its ability to produce measurements, even if the "algorithm" is inherent to the optical low coherence reflectometry technology itself rather than a distinct AI algorithm. The performance of the device's measurements was compared directly without human interpretation of its outputs in the validation.
7. Type of Ground Truth Used
The "ground truth" for the comparison studies was derived from the measurements obtained by legally marketed predicate devices. This means that the established and accepted accuracy of these existing devices (IOL-Master, OLCR, Accusonic A-Scan, Keratron) served as the reference for determining the equivalence of the LENSTAR LS 900's measurements.
8. Sample Size for the Training Set
The document does not mention a separate "training set" or its sample size. This is expected as the LENSTAR LS 900 is based on established optical principles (Optical Low Coherence Reflectometry) and does not describe a machine learning algorithm requiring a distinct training phase. Its development would involve engineering and calibration, not traditional machine learning training.
9. How the Ground Truth for the Training Set Was Established
As there is no mention of a training set for a machine learning algorithm, there is no corresponding description of how ground truth for a training set was established. The device relies on physical principles and instrument calibration rather than data-driven learning for its primary function.
§ 886.1850 AC-powered slitlamp biomicroscope.
(a)
Identification. An AC-powered slitlamp biomicroscope is an AC-powered device that is a microscope intended for use in eye examination that projects into a patient's eye through a control diaphragm a thin, intense beam of light.(b)
Classification. Class II (special controls). The device, when it is intended only for the visual examination of the anterior segment of the eye, is classified as Group 1 per FDA-recognized consensus standard ANSI Z80.36, does not provide any quantitative output, and is not intended for screening or automated diagnostic indications, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 886.9.