(267 days)
The iCare HOME2 tonometer is a prescription device intended as an adjunct to the routine clinical monitoring of intraocular pressure (IOP) of adult patients.
The iCare HOME2 tonometer (model TA023) is a hand-held, battery operated device which measures intraocular pressure (IOP) without the need for topical anaesthesia by rebound tonometry. The tonometer is to be used by the patients themselves. The tonometer uses the rebound method. A small and light, sterile, single-use probe makes brief contact with the eye. The device measures the deceleration of the probe and the rebound time and calculates the IOP from these parameters. Deceleration of the probe is slower at low IOP compared to high IOP. The measurement method, the IOP measurement algorithm and rebound technology (including disposable probe) are identical with the predicate device. iCare HOME2 tonometer is a further developed version of iCare HOME tonometer. It features enhancements such as possibility to measure IOP in any angle between 0° and 90° (horizontal to supine patient position) and possibility for wireless measurement result transfer to mobile device or to PC. External design and user interface have been modified for better usability and ergonomics. The measurement data can be uploaded to iCare CLINIC for further analysis using either iCare EXPORT (desktop application) or iCare PATIENT2 (mobile application). iCare PATIENT2 is a mobile app intended for transferring eye pressure measurement data from the iCare tonometer to the iCare CLINIC cloud service or an external system. The app displays the eye pressure measurement results and helps in glaucoma management. It is indicated for use by healthcare professionals and patients. Measurement results can be transferred to iCare CLINIC with either through a Bluetooth connection or by connecting the USB C type connector to the device and mobile phone, depending on the user's mobile phone operating system.
The iCare HOME2 tonometer is intended as an adjunct to the routine clinical monitoring of intraocular pressure (IOP) of adult patients.
Here's an analysis of the acceptance criteria and the study proving the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
The FDA clearance document for iCare HOME2 (K211355) does not explicitly list "acceptance criteria" in a bulleted or numbered format with specific thresholds. However, based on the provided "Performance and Safety Data" and "Clinical Performance Testing" sections, we can infer the implied acceptance criteria were related to accuracy, repeatability, and reproducibility compared to existing tonometers, as well as safety.
The key performance metric presented is the agreement between the iCare HOME2 and a reference tonometer (iCare IC200).
| Acceptance Criteria (Inferred from study design) | Reported Device Performance (iCare HOME2 vs. iCare IC200) |
|---|---|
| Accuracy and Agreement with Reference Tonometer (iCare IC200) | Overall (N=47 patients): |
- Mean paired difference (iCare HOME2 - iCare IC200): 0.55 mmHg
- Standard deviation of the difference: 2.69 mmHg
- 95% CI for Mean Difference: -0.86, -0.23 mmHg (Note: This range seems incorrectly transcribed in the original document as it does not align with the mean paired difference, it may be a typo. Usually, it would encompass the mean diff. Assuming the mean diff is correct.)
- 95% Limits of Agreement (LOA) for Mean Difference: -5.82, 4.72 mmHg (This indicates that 95% of the differences between the two devices fall within this range). |
| Repeatability (Variability of repeat measurements) | For each patient, variability (difference of repeat measurements) for all IOP ranges was ~7.9%. |
| Reproducibility (Agreement regardless of device, operator, or measurement angle) | Demonstrated high agreement with manometric pressure regardless of the device, operator, or the measurement angle (from bench testing). |
| Safety | No adverse events (including corneal abrasions) were recorded in the study population. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: 47 patients.
- Data Provenance: Prospective clinical study performed at East West Eye Institute, CA 90013, USA. The patients were either diagnosed glaucoma patients or 'glaucoma suspects'.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of those Experts
The document does not explicitly state the number of experts used or their qualifications for establishing the ground truth. The ground truth was established by comparison to a "reference tonometer (iCare IC200)," which is a cleared medical device. While healthcare professionals (likely ophthalmologists or technicians) would have operated both devices during the clinical study, their role in establishing a "ground truth" (beyond operating the reference device) for each patient's IOP is not detailed. The iCare IC200 itself is considered a "reference" for comparison.
4. Adjudication Method for the Test Set
The document does not describe any specific adjudication method (e.g., 2+1, 3+1). It appears a direct comparison between the iCare HOME2 measurements and the iCare IC200 measurements was performed. A "random eye was selected as the study eye for each patient."
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
The study described is not a Multi-Reader Multi-Case (MRMC) comparative effectiveness study involving human readers with and without AI assistance.** This device is a tonometer, a measurement device, not an AI-powered diagnostic imaging tool that assists human readers.** Therefore, this question is not applicable to the submitted document.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
The iCare HOME2 is a physical tonometer device that performs measurements. It has an "IOP measurement algorithm" that calculates IOP from probe deceleration and rebound time. The clinical study evaluated the performance of this device (which includes its internal algorithm) when used by patients (self-measurement) compared to a reference tonometer (likely operated by a healthcare professional). Therefore, in a sense, the measurement output itself is "standalone" from direct human interpretation of raw data, but it's a device measurement, not an AI algorithm assisting human interpretation.
7. The Type of Ground Truth Used
The ground truth for the clinical study was established by comparison to a legally marketed reference medical device: the iCare IC200 tonometer (cleared in K190316). In addition, bench testing used "manometrically controlled artificial cornea" for accuracy and reproducibility assessment, implying manometric pressure served as a higher-level ground truth in those tests. For the clinical study, the IC200 served as the comparative standard.
8. The Sample Size for the Training Set
The document does not provide information about a "training set" in the context of machine learning or AI. The iCare HOME2 tonometer uses a "rebound method" and an "IOP measurement algorithm," which are stated to be "identical with the predicate device." This suggests the core measurement algorithm was likely developed and validated prior to this submission (possibly with data from the predicate device iCare HOME), and this submission focuses on the safety and effectiveness of the new device iteration. No specific training set for a machine learning model is mentioned.
9. How the Ground Truth for the Training Set was Established
As no specific training set for an AI/machine learning model is mentioned for iCare HOME2, information on how its ground truth was established is not available in the provided document. The device's measurement principles are inherited from the predicate device.
§ 886.1930 Tonometer and accessories.
(a)
Identification. A tonometer and accessories is a manual device intended to measure intraocular pressure by applying a known force on the globe of the eye and measuring the amount of indentation produced (Schiotz type) or to measure intraocular tension by applanation (applying a small flat disk to the cornea). Accessories for the device may include a tonometer calibrator or a tonograph recording system. The device is intended for use in the diagnosis of glaucoma.(b)
Classification. Class II.