(78 days)
The Vistron CT Injection System is a syringe-based fluid delivery system indicated for delivery of contrast media during computed tomography applications. It is intended to be used for the specific purpose of injecting intravenous contrast medium into the human vascular system for diagnostic studies in computed tomography.
The Medrad Vistron CT Injection System is a programmable, syringe-based fluid delivery system for delivery of contrast media during computed tomography procedures. The Vistron CT Injector is comprised of three main components - Injector Head, System Power Unit (SPU), and Remote Monitor (a.k.a. Intelligent Hand Unit). The Medrad Vistron CT Injector System, like the predicate Vistron CT Injector System, uses a 125ml and 200ml Front Load Sterile Disposable Svringe. The only difference is that the modified Injector accommodates the use of an alternate 200ml contrast pre-filled syringe, and it now has an Imaging System Interface.
The Medrad Vistron CT Injection System is a programmable, syringe-based fluid delivery system for the delivery of contrast media during computed tomography procedures. The modified device accommodates an alternate 200ml contrast pre-filled syringe and now has an Imaging System Interface.
Here's an analysis of the acceptance criteria and study information provided:
1. Table of Acceptance Criteria and Reported Device Performance
The provided document describes the functional features of the Medrad Vistron CT Injection System and compares it to a predicate device (Medrad Vistron CT Injection System, K982814). The acceptance criteria are implied by the functional specifications that state the system performs as described or matches the predicate device.
| Feature | Acceptance Criteria (Modified Device) | Reported Device Performance |
|---|---|---|
| Programmed Volume | 10 ml to 125 ml or 10 ml to 200 ml depending on syringe size. | The volume of contrast medium delivered is settable for each phase of the injection profile. Range is 10 ml to 125 ml or 10 ml to 200 ml depending on the size of syringe used. |
| Programmed Flow Rate | 0.1 ml/sec to 9.9 ml/sec, settable in 0.1 ml/sec increments for each phase. | The flow rate is the ratio of fluid volume delivered to the injection duration (ml/sec) and is settable, in 0.1 ml/sec increments, for each phase of the injection profile. Range is 0.1 ml/sec to 9.9 ml/sec. |
| Pressure Limiting | Settable from 50 psi to 300 psi in 50 psi increments. Injection proceeds at reduced flow or terminates on stall. | System has a settable pressure limit, range 50 psi to 300 psi with increments of 50 psi. If reached, injection proceeds at reduced flow or terminates on stall. User alerted via audible beeps and indicator light. |
| Program Parameters | User can program fluid volume, flow rate, injection duration, pressure limit, phase/level, and scan delay. | The user can program the injector with fluid volume, flow rate, injection duration, pressure limit value, program phase/level, and scan delay parameters. |
| Injection Profile | Sequence of one or more phases, up to a maximum of 4. | The user can program a sequence of one or more program phases, up to a maximum of 4, in which each phase delivers fluid according to the program parameters defined for that phase. |
| Hold Capability | Remains armed, injection stops when enabled, resumes when cancelled. Max 10 minutes, then disarms. | "Hold" allows the user to temporarily interrupt an injection. System remains armed, injection stops until cancellation, then resumes. Remains in "Hold" for max 10 minutes, after which unit disarms, audible beep, message displayed. |
| Scan Delay | 0-99 seconds. Audible beep and countdown clock at 0. | "Scan Delay" is a function user can program (0-99 seconds). Interval begins simultaneously with first phase. Visible countdown clock (1 second increments). Audible beep when countdown reaches 0. |
| Autofill | Load specified amount (25, 50, 75, 100, 125, 150, 175, or 200ml) at 2ml/sec. Non-functional with alternate 200ml syringe. | "Autofill" allows the user to load a specified amount of fluid into a syringe (25, 50, 75, 100, 125, 150, 175, or 200ml depending on syringe size). Fill rate fixed at 2ml/sec. Non-functional when an alternate 200ml syringe is installed. |
| Single/Multi Arm | Single Arm: executes once, then disarms. Multi Arm: repeats without re-arming until insufficient contrast. | User can select "Single Arm" (single injection, then disarms) or "Multiple Arm" (repeats programmed injection without re-arming until insufficient contrast). Alerts user if insufficient volume for full injection. |
| Syringe Sensing | Determines syringe size (125ml, 200ml, alternate 200ml) and proper installation. Adjusts parameters, error message if not installed. | "Syringe Sensing" determines which compatible Medrad syringe size (125ml, 200ml cr an alternate 200ml contrast prefilled syringe) is installed and senses proper installation. Adjusts pressure, volume, flow. Issues error message if improperly installed. |
| Syringe Heater | Maintains preheated contrast medium temperature within 87.8° to 105.8°F. | Maintains the temperature of preheated contrast medium within the syringe from 87.8° to 105.8°F. |
| Safety Stop | Continuously monitors critical functions, secondary microprocessor checks for over-volume, over-flow, pressure/stall, hardware comparator for over-pressure. Opens relay to cut power, enters maintenance state. | All critical system functions continuously monitored. Secondary microprocessor monitors for over-volume, over flow rate, and pressure/stall; hardware comparator for over-pressure. Opens relay to cut power, maintenance state. |
| Retract Control | Returns piston to fully retracted. Operates only when syringe is detached. | Control provided to return the piston to its fully retracted station. Only operational when the syringe is detached. Syringe Sensing detects syringe presence. |
| Imaging System Interface (ISI) | Interconnects Injector Head and Remote Monitor, provides isolated interface with CT Scanner. Receives inputs from CT to initiate/stop, controls outputs to activate scan. Verifies functionality. | Resides in SPU, acts as interconnect for Injector Head and Remote Monitor. Provides isolated interface with CT Scanner. One input (two signal lines), one output (three signal lines). Controlled by Remote Controller. Receives CT inputs to initiate/stop injection, controls outputs to activate scan. Verifies input/output signals. |
| Syringe System Accommodation | 200ml, 125ml, Alternate 200ml | The only difference is that the modified Injector accommodates the use of an alternate 200ml contrast pre-filled syringe. (Also 125ml and 200ml Front Load Sterile Disposable Syringe) |
2. Sample Size Used for the Test Set and Data Provenance
The document mentions "design verification and validation testing was conducted" and "Test results concluded that the design specifications for the Vistron CT Injection System were met." However, it does not provide details on the sample size used, the specific tests performed, or the provenance of any data (e.g., country of origin, retrospective or prospective). It only states that these tests were conducted as part of design controls in compliance with FDA's Quality System Requirements.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not provided in the document. The testing described appears to be engineering verification and validation against technical specifications rather than clinical performance evaluation requiring expert ground truth in the traditional sense of medical image analysis.
4. Adjudication Method for the Test Set
This information is not provided in the document. As noted above, the testing appears to be technical validation, not a multi-expert clinical evaluation.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size
A Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. The document describes technical verification and validation of a medical device, focusing on its functional specifications and safety, not on human reader performance with or without AI assistance. The device itself is an injector system, not an AI or imaging diagnostic tool that would typically be evaluated with MRMC studies.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
This question is not applicable as the device is a contrast injection system with no "algorithm only" component that would perform diagnostic or analytical tasks independently. Its "intelligence" is in its programmable features and safety mechanisms, which assist human operators. The testing performed would be considered standalone in the sense that the device's technical functions were verified, but not in the context of an AI algorithm's performance.
7. The Type of Ground Truth Used
The "ground truth" for the tests described is the engineering design specifications and recognized industry standards. The device's performance was compared against these predefined criteria (e.g., flow rate, pressure limits, temperature range, correct syringe sensing, safety stop functionality). This is not expert consensus, pathology, or outcomes data.
8. The Sample Size for the Training Set
This information is not applicable/not provided. The device is an electro-mechanical system with embedded software, not a machine learning or AI algorithm that requires a "training set" in the conventional sense. The software operates based on predefined logic and parameters, not on learned patterns from a dataset.
9. How the Ground Truth for the Training Set Was Established
This information is not applicable/not provided for the same reasons as #8. There is no training set for this type of device. The software "logic" is established through design and programming based on functional requirements and safety considerations.
§ 870.1650 Angiographic injector and syringe.
(a)
Identification. An angiographic injector and syringe is a device that consists of a syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography.(b)
Classification. Class II (special controls). The device, when it is a non-patient contacting balloon inflation syringe intended only to inflate/deflate balloon catheters and monitor pressure within the balloon, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 870.9.