(426 days)
To drain cerebrospinal fluid (CSF) for the management of hydrocephalus.
The Sophy® Pressure Adjustable Valve System SU8 is an implantable device designed for the treatment of hydrocephalus in adult and pediatric patients by shunting, thereby providing continuous, controlled intraventricular pressure and CSF drainage from the cerebral ventricles. Intraventricular pressure is maintained at a constant level by the device's ball-in-cone valve seat design, and the valve is pressure-adjustable transcutaneously. Drainage is directed to the abdominal cavity or to the right atrium of the heart. The Sophy® Pressure Adjustable Valve System SU8 technology allows for the non-invasive manual adjustment of the operating pressure via 8 pressure settings, ranging from 50 mm H20 to 170 mm, as follows: 50 = Low, 110 = Medium (intermediate 65,80,95), and 170 = High (intermediate 130, 150). The principle of the Sophy® Adiustable Valve System SU8, identical to that of several existing FDA cleared hydrocephalus valves, is based on the pressure change exerted on a synthetic ruby ball by a semi-circular spring at different points of its curvature. This spring is connected to a magnetic rotor whose position can be adjusted non-invasively by using a programming magnet oriented at different angles with selected orientations corresponding to different pressures. Radio-opaque identification dots indicate three main positions of the rotor corresponding to Low, Medium, and High operating pressures. For pressure setting, a specific programming kit is necessary, including a compass, magnet, and pressure selector.
Here's an analysis of the provided text regarding the acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria & Reported Device Performance:
| Acceptance Criteria Category | Specific Criteria/Tests Conducted | Reported Device Performance |
|---|---|---|
| Mechanical/Physical Performance | Material and Corrosion | Complies with ASTM F647-94; suitable for intended use. |
| Diffusion of Samarium and Cobalt into the Valve | Complies with ASTM F647-94; suitable for intended use. | |
| Sensitivity to Angular Accelerations and Shocks | Complies with ASTM F647-94; suitable for intended use. | |
| Pressure-Flow Studies | Complies with ASTM F647-94; suitable for intended use. | |
| Pressure-Adjustment and Rotor Programming | Complies with ASTM F647-94; suitable for intended use. | |
| Magnetic and MRI Tests | Complies with ASTM F647-94; suitable for intended use. | |
| Biocompatibility | Biocompatibility tests per Tripartite Biocompatibility Guidance for Medical Devices and ISO 10993 | Device materials are biocompatible. |
| Clinical Performance (Safety & Effectiveness) | Perform "as well as" and be "safe and effective as currently marketed hydrocephalus shunts." | Retrospective clinical study results indicated that the Sophy® Pressure-Adjustable Valve System SU8 performs as well as, and is safe and effective as currently marketed hydrocephalus shunts. Specifically, it demonstrated near identical performance to the Hakim Programmable Valve (K974739). |
2. Sample Size Used for the Test Set and Data Provenance:
- Sample Size for Clinical Study (Test Set): 43 consecutive patients (25 pediatric, 18 adults)
- Data Provenance: The study was a retrospective clinical study. The document does not specify the country of origin of the data.
3. Number of Experts Used to Establish Ground Truth for Test Set & Qualifications:
This information is not provided in the given text. The text only states that a "retrospective clinical study" was conducted and "results indicated that the Sophy® Pressure-Adjustable Valve System SU8 performs as well as, and is safe and effective as currently marketed hydrocephalus shunts." There's no mention of specific experts establishing ground truth for individual cases within this study.
4. Adjudication Method for the Test Set:
The adjudication method is not specified in the provided text.
5. Multi Reader Multi Case (MRMC) Comparative Effectiveness Study:
A MRMC comparative effectiveness study was not explicitly described as being performed in the provided text. The clinical study was a direct patient outcome study, not a study comparing human readers' performance with and without AI assistance.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study:
This is not applicable as the device described is a physical medical device (hydrocephalus shunt), not an AI-driven algorithm. The testing described focuses on the device's physical and clinical performance.
7. Type of Ground Truth Used:
The ground truth for the clinical study was based on patient outcomes/clinical performance data over a follow-up period (1 year follow-up in 93% of patients, 2 year follow-up in 59%). The comparison was made against the performance of "currently marketed hydrocephalus shunts."
8. Sample Size for the Training Set:
This is not applicable as the device is a physical medical device, not a machine learning algorithm that requires a training set. The performance testing was based on engineering and clinical evaluations.
9. How the Ground Truth for the Training Set Was Established:
This is not applicable for the same reason as above (physical medical device, no training set).
§ 882.5550 Central nervous system fluid shunt and components.
(a)
Identification. A central nervous system fluid shunt is a device or combination of devices used to divert fluid from the brain or other part of the central nervous system to an internal delivery site or an external receptacle for the purpose of relieving elevated intracranial pressure or fluid volume (e.g., due to hydrocephalus). Components of a central nervous system shunt include catheters, valved catheters, valves, connectors, and other accessory components intended to facilitate use of the shunt or evaluation of a patient with a shunt.(b)
Classification. Class II (performance standards).