(149 days)
EpiMonitor is a prescription only medical device system composed of a wearable device "EmbracePlus" and paired mobile software application "EpiMonitor" intended as an adjunct to seizure monitoring in adults and children aged 6 and up in a home environment or healthcare facilities. The device is worn on the wrist and senses Electrodermal Activity (EDA) and motion data to detect patterns that may be associated with either primary or secondary generalized tonic clonic clonic clonic seizures in patients with epilepsy or at risk of having epilepsy. When a seizure event is detected, the wearable device component of EpiMonitor sends a command to a paired mobile device where the EpiMonitor App is programmed to initiate an alert to a designated caregiver. The EpiMonitor app incorporates additional detection sensitivity modes, "high" for use during periods of rest or sleeping or "low" for use during periods of low-intensity activity, in order to reduce false alarm incidents.
EpiMonitor records, stores and transmits accelerometer. EDA, peripheral skin temperature and activity data for subsequent retrospective review by a trained healthcare professional via a cloud-based software.
The EpiMonitor system consists of a wearable device and mobile application:
- A wearable medical device called EmbracePlus,
- A mobile application running on smartphones called "EpiMonitor"
The EmbracePlus is worn on the user's wrist and continuously collects raw data via specific sensors, these data are continuously analyzed by an on-board algorithm (EpiAlgo 2.1), which assesses the physiological data and determines if the user may be undergoing a generalized tonic-clonic seizure (GTCS). The EpiAlgo has been validated through testing, using the gold-standard video-Electroencephalogram (EEG) methodology designed by a group of epileptologists at a top level 4 epilepsy center, from epilepsy patients experiencing GTCSs in hospital Epilepsy Monitoring Units. When a likely GTCS is detected, EmbracePlus sends, via Bluetooth Low Energy, a message to the EpiMonitor app. The EpiMonitor app communicates to the Empatica Cloud which initiates, through the external provider a voice call and SMS text message is sent to summon the attention of userdesignated caregiver(s).
In addition to initiating alerts, the EpiMonitor app also continuously receives all the raw sensor data collected by the EmbracePlus. These data are analyzed by one of the EpiMonitor app software modules, EmpaDSP (paragraph 2.3.2), which computes the additional physiological parameters, such as activity during sleep and peripheral skin temperature.
The EpiMonitor App is also responsible for transmitting, over a cellular data plan or Wi-Fi connection the sensors' raw data, device information, and computed physiological parameters to the Empatica Cloud. On the Empatica Cloud, these data are stored, and made available to healthcare providers via a specific cloud-based software called Care Monitoring Portal.
Here's a breakdown of the acceptance criteria and study details for the EpiMonitor device, derived from the provided FDA 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for the EpiMonitor device's Low-Sensitivity mode were evaluated based on Positive Percent Agreement (PPA) for seizure detection and False Alarm Rate (FAR) for both Epilepsy Monitoring Unit (EMU) data and real-world data.
| Metric (Low-Sensitivity Mode) | Acceptance Criteria (Implicit from "Acceptable") | Reported Device Performance (EMU Data) | Reported Device Performance (Real-World Data) |
|---|---|---|---|
| Positive Percent Agreement (PPA) | Acceptable seizure detection accuracy | Age 6-21: 0.895 (corrected 0.791, CI: 0.619-0.925) | |
| Age >21: 1.000 (corrected 0.905, CI: 0.891-0.917) | Age 6-21: 0.87 (corrected 0.86, CI: 0.78-0.92) | ||
| Age >21: 0.80 (corrected 0.77, CI: 0.64-0.87) | |||
| False Alarm Rate (FAR) per 24 hours | Reduced rate of false alerts | Age 6-21: 0.70 (Overall), 0.91 (Mean) | |
| Age >21: 0.28 (Overall), 0.33 (Mean) | Age 6-21: 0.34 (Overall), 0.35 (Mean) | ||
| Age >21: 0.25 (Overall), 0.29 (Mean) |
Note: The document explicitly states "Analysis of performance for the Low-Sensitivity alerting mode in the EpiMonitor system demonstrated acceptable seizure detection accuracy and a reduced rate of false alerts." This implies that the reported performance met the sponsor's internal acceptance criteria for these metrics. Specific numerical thresholds for "acceptable" are not explicitly stated within the provided text.
2. Sample Sizes Used for the Test Set and Data Provenance
For Epilepsy Monitoring Unit (EMU) Data (Retrospective Analysis):
- Seizure Detection (PPA):
- Patients: 24 (12 for age 6-21, 12 for age >21)
- GTCS events: 36 (19 for age 6-21, 17 for age >21)
- False Alarm Rate (FAR):
- Patients: 141 (80 for age 6-21, 61 for age >21)
- Days of monitoring: 241.62 (88.94 for age 6-21, 152.68 for age >21)
- Data Provenance: The data was collected from patients observed in Epilepsy Monitoring Units. The exact geographic origin (country) is not specified, but the data was from "a top level 4 epilepsy center" (mentioned in device description for original EpiAlgo validation). This was a retrospective analysis of previously collected clinical data.
For Real-World Data (Longitudinal Analysis) - based on Embrace2 wearable device:
- Seizure Detection (PPA):
- Patients: 1444 (601 for age 6-21, 843 for age >21)
- GTCS events: 4782 (1157 for age 6-21, 3625 for age >21)
- False Alarm Rate (FAR):
- Patients: 1444 (601 for age 6-21, 843 for age >21)
- Days of monitoring: 93983.3 (37594.2 for age 6-21, 56389.1 for age >21)
- Data Provenance: "real-world data" captured using the Embrace2 wearable device, likely from home settings. The exact geographic origin (country) is not specified. This was a retrospective longitudinal analysis of real-world data.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
The document states that the EpiAlgo was validated "using the gold-standard video-Electroencephalogram (EEG) methodology designed by a group of epileptologists at a top level 4 epilepsy center". It also refers to "adjudicated tonic-clonic seizure data" for the EMU data. This implies that epileptologists were involved in establishing the ground truth.
- Number of experts: Not explicitly stated, but referred to as "a group of epileptologists."
- Qualifications of experts: "epileptologists at a top level 4 epilepsy center." No specific experience (e.g., 10 years of experience) is detailed.
4. Adjudication Method for the Test Set
The document mentions "adjudicated tonic-clonic seizure data" for the EMU study. However, the specific adjudication method (e.g., 2+1, 3+1) is not explicitly described in the provided text.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- Was an MRMC study done? No.
- The study focuses on the performance of the algorithm itself (standalone and with different sensitivity modes), not on how human readers improve with or without AI assistance.
- The effect size of human readers improving with AI vs. without AI assistance is not applicable as this type of study was not performed.
6. Standalone (Algorithm Only) Performance Study
- Yes, a standalone study was done. The entire performance analysis for PPA and FAR presented in Tables 1-4 reflects the algorithm's performance (EpiAlgo ver 2.1) using the Low-Sensitivity mode, without human intervention in the detection process. The device detects an event, and the app initiates an alert; there's no mention of a human-in-the-loop directly influencing the detection sensitivity.
7. Type of Ground Truth Used
- Expert Consensus / Gold Standard (Video-EEG): The ground truth for seizure events was primarily established using gold-standard video-Electroencephalogram (EEG) methodology and "adjudicated tonic-clonic seizure data." This indicates expert consensus based on clinical and physiological evidence.
8. Sample Size for the Training Set
The provided text does not specify the sample size used for the training set of the EpiAlgo. It only describes the validation phases for the Low-Sensitivity mode.
9. How the Ground Truth for the Training Set Was Established
The provided text states: "The EpiAlgo has been validated through testing, using the gold-standard video-Electroencephalogram (EEG) methodology designed by a group of epileptologists at a top level 4 epilepsy center, from epilepsy patients experiencing GTCSs in hospital Epilepsy Monitoring Units."
This implies that the training data's ground truth was established by epileptologists using video-EEG data from patients with generalized tonic-clonic seizures (GTCSs) in hospital Epilepsy Monitoring Units. This is consistent with clinical gold standards for seizure identification.
§ 882.1580 Non-electroencephalogram (EEG) physiological signal based seizure monitoring system.
(a)
Identification. A non-electroencephalogram (non-EEG) physiological signal based seizure monitoring system is a noninvasive prescription device that collects physiological signals other than EEG to identify physiological signals that may be associated with a seizure.(b)
Classification. Class II (special controls). The special controls for this device are:(1) The technical parameters of the device, hardware and software, must be fully characterized and include the following information:
(i) Hardware specifications must be provided. Appropriate verification, validation, and hazard analysis must be performed.
(ii) Software, including any proprietary algorithm(s) used by the device to achieve its intended use, must be described in detail in the Software Requirements Specification (SRS) and Software Design Specification (SDS). Appropriate software verification, validation, and hazard analysis must be performed.
(2) The patient-contacting components of the device must be demonstrated to be biocompatible.
(3) The device must be designed and tested for electrical, thermal, and mechanical safety and electromagnetic compatibility (EMC).
(4) Clinical performance testing must demonstrate the ability of the device to function as an assessment aid for monitoring for seizure-related activity in the intended population and for the intended use setting. Performance measurements must include positive percent agreement and false alarm rate.
(5) Training must be provided for intended users that includes information regarding the proper use of the device and factors that may affect the collection of the physiologic data.
(6) The labeling must include health care professional labeling and patient-caregiver labeling. The health care professional and the patient-caregiver labeling must include the following information:
(i) A detailed summary of the clinical performance testing, including any adverse events and complications.
(ii) Any instructions technicians and clinicians should convey to patients and caregivers regarding the proper use of the device and factors that may affect the collection of the physiologic data.
(iii) Instructions to technicians and clinicians regarding how to set the device threshold to achieve the intended performance of the device.