(41 days)
The LADARWave® CustomCornea® Wavefront System is used for measuring, recording, and analyzing visual aberrations (such as myopia, astigmatism, coma and spherical aberration) and for displaying refractive error maps of the eye to assist in prescribing refractive corrections.
This device is enabled to export wavefront data and associated anatomical registration information to a compatible treatment laser where a wavefront-guided treatment is indicated.
This device can also export centration data and associated registration information for conventional phoropter-based refractive surgery with the LADAR6000™ System.
The LADARWave® CustomCornea® Wavefront System is an aberrometer, utilizing Hartmann-shack wavefront sensing to measure the aberrations in the human eye. The device contains four major optical subsystems used in the clinical wavefront examination.
- A fixation subsystem provides the patient with an unambiguous point of fixation. . Optics in this path automatically adjusts to correct for the patient's spherocylindrical error so that the target is clearly observed.
- A video subsystem provides the device operator with a view of the eye at the . measurement plane. The operator uses the video imagery to position the eye for the measurement and to record the geometry of the wavefront relative to anatomical features.
- A probe beam subsystem directs a narrow beam of eye-safe infrared radiation . into the eye to generate the re-emitted wavefront.
- A wavefront detection subsystem images the re-emitted wavefront onto the . entrance face of the Hartmann-shack wavefront sensor.
These subsystems are all under control of the device software.
Once the wavefront examination is complete, the operator may export the exam data to removable media. The exported electronic file contains all information necessary to perform customized ablative surgery using either the LADARVision®4000 or LADAR6000" System. The information includes the wavefront measurement, essential patient identification information, and geometric registration data. The electronic file is in a proprietary format and is encrypted so that wavefront data cannot be exported for use by an incompatible treatment device.
Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:
Acceptance Criteria and Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| The accuracy in translational (x,y) and cyclotorsional registration for the "overlay" method must be at least as good as with the current "sputnik" method to establish equivalence of the new automated registration process. | The results demonstrate that the "overlay" method is as good or better than the "sputnik" method in offset registration and rotational registration at all values of registration error (i.e. at all x-axis values). Additionally, system level software verification and validation were successfully completed in accordance with General Principles of Software Validation; Final Guidance for Industry and FDA Staff dated January 11, 2002. |
Study Details:
-
Sample Size used for the test set and the data provenance:
- The text states, "For each eye, one LADARWave wavefront session (centration photo and five wavefront measurements with associated photos) with eye marks and a session without eye marks were taken for the testing." This implies that multiple eyes were used, but a specific number is not provided.
- Data Provenance: Not explicitly mentioned (e.g., country of origin). The study appears to be retrospective or a controlled prospective study specifically for this submission, as it compares two methods ("sputnik" and "overlay") on the same eyes.
-
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- This information is not provided in the document. The method of "comparing" the two registration methods ("sputnik" and "overlay") suggests a quantitative assessment rather than expert consensus for ground truth on registration accuracy directly.
-
Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- This information is not provided in the document. The comparison seems to be based on direct measurement of registration accuracy between the two methods rather than an adjudication process involving human reviewers.
-
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 explicitly mentioned or described. The study focused on comparing two registration methods (manual "Sputnik" vs. automated "Overlay") for the device itself, rather than evaluating human reader performance with or without AI assistance. The "overlay" method is described as an "assisted" registration method, suggesting it might involve some automation, but the study design is not an MRMC study comparing human performance.
-
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- The "overlay" method is described as an "assisted" registration method, implying some level of automation. The testing compared this "overlay" method to the "current manual 'Sputnik' method." The study's focus was on establishing the equivalence of the automated/assisted registration process, which is a standalone function of the software, to the existing manual method. Therefore, a standalone performance assessment of the "overlay" method's accuracy in registration, compared to a manual method, was performed.
-
The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- The ground truth for registration accuracy appears to be derived from direct comparisons between the outcomes of the "sputnik" and "overlay" methods. The statement "The primary test was to establish equivalence of the two methods of registration by testing that the accuracy in translational (x,y) and cyclotorsional registration for the 'overlay' method are at least as good as with the current 'sputnik' method" suggests that the "sputnik" method provides a baseline or reference against which the "overlay" method's accuracy is measured. This implies a comparative ground truth derived from a reference method rather than an independent expert consensus, pathology, or outcomes data.
-
The sample size for the training set:
- This information is not provided in the document. The document describes testing the automated registration process, but does not detail the development or training of the "overlay" software.
-
How the ground truth for the training set was established:
- This information is not provided in the document. Since the training set size is not mentioned, the method for establishing its ground truth is also absent.
§ 886.1760 Ophthalmic refractometer.
(a)
Identification. An ophthalmic refractometer is an automatic AC-powered device that consists of a fixation system, a measurement and recording system, and an alignment system intended to measure the refractive power of the eye by measuring light reflexes from the retina.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter, subject to the limitations in § 886.9.