(137 days)
The Cyberwand Dual Probe Lithotripter is intended to be used for the fragmentation of urinary tract calculi in the kidney, ureter and bladder.
The Cybersonics, Cyberwand Dual Probe Ultrasonic Lithotripsy system is an electromechanical device capable of fragmenting and aspirating calculi. The hand piece consists of an ultrasonic transducer containing the piezo-electronic elements, which are driven by a generator operating at 21 ± 1 kHz. The resulting longitudinal waves are propagated along the ultrasonic dual probe to the target stone. The ultrasonic transducer probes are hollow, permitting simultaneous suction.
The provided K052135 document describes the Cybersonics Cyberwand Dual Probe Lithotripter, which is intended for the percutaneous fragmentation and removal of kidney stones. The basis for substantial equivalence is primarily against other legally marketed ultrasonic lithotripters, specifically the EMS Swiss Lithoclast Ultra (K012445) and the Karl Storz Calcuson (K973251).
Acceptance Criteria and Study Details
The document does not explicitly state "acceptance criteria" as a set of quantified thresholds. Instead, it presents a comparison of technological characteristics and performance metrics, particularly drill rate, against predicate devices to demonstrate substantial equivalence. The implication is that if the Cyberwand performs "as well or better" than the predicates, it meets the unstated acceptance criteria for safety and effectiveness.
Here’s a breakdown of the information requested based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criterion (Implied) | Reported Device Performance (Cybersonics Cyberwand) | Predicate Performance (e.g., LithoClast Ultra) |
|---|---|---|
| Technological Characteristics: | ||
| Operating Frequency | 20–22 kHz | 24–26 kHz (LithoClast Ultra); 25–26kHz (Storz Calcuson) |
| Utilities | 120–240 Vac | 120–240 Vac |
| Autoclavable probes and hand piece | Yes | Yes |
| Probes threaded for assembly | Yes | Yes |
| Probe length (standard) | 400 mm | 400 mm |
| Probe OD ≤ 3.75mm | Yes | Yes |
| Ultrasonic Probe tip excursion ≤100 µm | Yes | Yes |
| Detachable hand piece | Yes | Yes |
| Handpiece with rear suction connection | Yes | Yes |
| Piezo stack with Titanium horn | Yes | Yes |
| Detachable footswitch | Yes | Yes |
| Table Top Generator | Yes | Yes |
| Applied Part BF | Yes | Yes |
| Performance (Drill Rate): | ||
| Mean Drill Rate (seconds) | 8.7 +/- 0.9 | 10.9 +/- 1.0 (LithoClast Ultra) |
Notes on Acceptance Criteria: The document primarily focuses on demonstrating that the Cyberwand's technological characteristics are comparable to predicate devices. For performance, the "acceptance criterion" appears to be that its drill rate is comparable to or better than predicate devices. The study results show the Cyberwand had a faster mean drill rate than all listed predicate devices.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size (Drill Rate Study):
- Cybersonics Cyberwand: 10 stones
- LithoClast Ultra: 10 stones
- Olympus LUS-2: 25 stones
- Circon-ACMI USL-2000: 25 stones
- Karl Storz Calcuson: 15 stones
- Olympus LUS-1: 12 stones
- Richard Wolf Model 2271-004: 10 stones
- Data Provenance: The drill rate data was supplied by Indiana University School of Medicine. This suggests a prospective study specifically designed for this comparison.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of Those Experts
This information is not provided in the document. The "ground truth" for the drill rate study appears to be the objective measurement of time taken to drill artificial stones. There is no mention of experts establishing a subjective ground truth.
4. Adjudication Method for the Test Set
This information is not applicable/provided. The drill rate study involves objective measurements of time, not subjective assessments requiring adjudication.
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 comparative effectiveness study was done. This device is a medical instrument (lithotripter), not an AI-powered diagnostic or assistive tool for human readers. Therefore, the concept of human readers improving with AI assistance is not relevant to this submission.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
- Yes, a standalone performance study was done in the form of the drill rate comparison. The "algorithm" here is the device itself, and its performance (drill rate) was measured independently without human intervention influencing the fragmentation process, beyond operating the device.
7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.)
- The ground truth for the drill rate study was objective performance measurement based on artificial stone fragmentation time. This is a direct physical measurement, not dependent on expert consensus, pathology, or clinical outcomes data.
8. The Sample Size for the Training Set
- Not applicable/provided. This submission does not describe a machine learning or AI algorithm that would require a training set. The device is a physical electromechanical lithotripter.
9. How the Ground Truth for the Training Set was Established
- Not applicable/provided for the reasons stated above (no AI/ML training set).
§ 876.4480 Electrohydraulic lithotriptor.
(a)
Identification. An electrohydraulic lithotriptor is an AC-powered device used to fragment urinary bladder stones. It consists of a high voltage source connected by a cable to a bipolar electrode that is introduced into the urinary bladder through a cystoscope. The electrode is held against the stone in a water-filled bladder and repeated electrical discharges between the two poles of the electrode cause electrohydraulic shock waves which disintegrate the stone.(b)
Classification. Class II. The special control for this device is FDA's “Guidance for the Content of Premarket Notifications for Intracorporeal Lithotripters.”