(87 days)
The Venometer Strain Gauge Plethysmograph is a hydraulic plethysmograph used to estimate the blood flow in thighs and calves of the body. Its primary purpose is as a screening device for deep vein thrombosis.
The Venometer is a portable instrument with which nurses can test patients at their bedside for potentially fatal blood clots in their legs. It first inflates a pressure cuff around the thigh to allow veins to fill with blood, and then releases this pressure and measures this pressure and measures the rate at which the veins subsequently empty. It automatically calculates the likelihood of a DVT based on these measurements. The Advanced Medical Technology Venometer is a noninvasive measurement system in which a silicon rubber tube filled with an electrically conductive liquid metal is wrapped around a patient's leg. Any change in girth will stretch the tubing, thus changing the resistance of the material in the tubing in proportion to the change in girth. This resistance change is converted by an electronic circuit to a voltage that can be easily measured and recorded. The electrically conductive liquid metal is an alloy of gallium and indium. A computer has been incorporated into the Venometer to provide step-by-step guidance for the operator throughout the test as a way of minimizing operator error; and to eliminate the need for an operator to consult a chart to make a diagnosis.
Here's an analysis of the provided text regarding the Advanced Medical Technology Limited Venometer, structured to address your request:
Based on the provided text, the submission focuses on asserting substantial equivalence to a predicate device rather than presenting a performance study with explicit acceptance criteria. The document highlights safety and efficacy through compliance with European standards for risk analysis, electromagnetic compatibility, and general medical electrical equipment standards. There is no mention of a clinical performance study with specific acceptance criteria or device performance data as one would typically find in a modern 510(k) submission for a diagnostic device.
Therefore, many of the requested elements for describing the acceptance criteria and the study that proves the device meets them cannot be fully answered from this regulatory document.
Acceptance Criteria and Reported Device Performance
The document does not explicitly state specific acceptance criteria for clinical performance (e.g., sensitivity, specificity, accuracy for DVT detection) nor does it provide a table of reported device performance metrics against such criteria. The focus is on demonstrating safety and general efficacy through compliance with manufacturing and design standards, and substantial equivalence to a predicate device.
Table 1: Acceptance Criteria and Reported Device Performance (Information Not Provided in Text)
| Performance Metric | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| No specific clinical performance criteria or results are provided in the document. | ||
| The document focuses on regulatory compliance and substantial equivalence to a predicate device for safety and general efficacy. | ||
| Safety (e.g., electrical safety, EMC) | Compliance with European Standards (prEN1441:1994, EN55011, EN60601-1) | Certified as in compliance. |
Detailed Study Information (Based on Available Text)
2. Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective)
- The document does not describe a clinical performance study with a test set of patient data. It focuses on engineering and regulatory compliance. The "test" mentioned refers to compliance with European standards for safety (prEN1441:1994, EN55011, EN60601-1) rather than a clinical performance evaluation.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- This information is not applicable as no clinical performance study with a test set and ground truth establishment is described.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set
- This information is not applicable as no clinical performance study with a test set requiring adjudication is described.
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 study or AI assistance is mentioned. The device is described as a standalone diagnostic tool, not one designed to augment human reading or incorporate AI.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- The document describes the Venometer as a standalone instrument that provides "step-by-step guidance for the operator throughout the test" and "automatically calculates the likelihood of a DVT." This suggests a standalone performance, although no specific performance data is provided in this document. The device's primary purpose is described as a "screening device," and the text notes that "a Nurse can rule out DVT with ten minutes at the bedside." While this implies standalone use, there's no formal "standalone performance study" report here with metrics like sensitivity or specificity.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- This information is not applicable as no clinical performance study with a ground truth reference is described. The device's mechanism suggests its output (likelihood of DVT based on blood flow measurements) would ideally be compared to a definitive diagnostic method for DVT (e.g., venography, ultrasound), but no such comparison is reported.
8. The sample size for the training set
- The document does not mention a training set. This device, based on strain gauge plethysmography, is likely based on established physiological principles and signal processing rather than machine learning requiring a training set.
9. How the ground truth for the training set was established
- This information is not applicable as no training set is mentioned.
Summary of what is present:
The 510(k) notification for the Advanced Medical Technology Limited Venometer focuses on demonstrating substantial equivalence to an existing legally marketed device (Medasonics Incorporated Model SPG16 Strain Gauge Plethysmograph, K782132). The safety and efficacy claims are primarily backed by:
- Compliance with European Standards:
- prEN1441:1994 for Risk Analysis.
- EN55011 for Electromagnetic Compatibility (meeting Class A limits).
- EN60601-1 for design and manufacture of medical electrical equipment.
- Technological Equivalence: The device uses a similar "electrically conductive liquid metal" strain gauge technology licensed from the manufacturer of the predicate device.
- Operational Guidance: A computer provides step-by-step guidance and automatically calculates DVT likelihood to minimize operator error and obviate chart consultation.
The document does not include a detailed clinical performance study with quantitative acceptance criteria (e.g., sensitivity, specificity, accuracy) or corresponding results for detecting DVT in a patient cohort. This type of submission relies heavily on the established safety and efficacy of the predicate device and the similarity of the new device's technology and intended use.
§ 870.2780 Hydraulic, pneumatic, or photoelectric plethysmographs.
(a)
Identification. A hydraulic, pneumatic, or photoelectric plethysmograph is a device used to estimate blood flow in a region of the body using hydraulic, pneumatic, or photoelectric measurement techniques.(b)
Classification. Class II (performance standards).