(55 days)
The ASLS is indicated for the placement of synthetic monofilament sutures in soft tissues and for the ligation of tubular structures wherever conventional monofilament sutures or surgical staples are appropriate. The ASLS is indicated for use in both traditional open surgery and ondoscopic surgical procedures.
The Axya Automatic Suturing and Ligating System (ASLS) is a device for the placement of sutures in soft tissue to close either traumatic or surgically produced wounds. It uses curved, hollow needles to place the suture through soft tissue structures and secures the suture loop with an ultrasonic weld. The ultrasonic energy source used to weld and secure the suture loop is similar to the energy source used in the UltraCision Harmonic Scalpel. The device is sterilized by exposure to gamma irradiation.
Here's an analysis of the provided text regarding the Axya Automatic Suturing and Ligating System (ASLS), broken down into the requested categories:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance |
|---|---|---|
| Suture Strength (Efficacy) | "Knot strength" substantially above USP requirements for respective suture sizes/types. | Sutures placed by ASLS exhibit "knot strength" characteristics substantially above the USP requirements for the respective sizes and types of suture materials tested. |
| Holding strength equivalent to conventional knotting techniques for synthetic monofilament sutures. | Synthetic monofilament sutures placed with ultrasonic welding are equivalent in holding strength (efficacy) to sutures placed with conventional knotting techniques. | |
| Strength Retention (Efficacy for Absorbable Sutures) | Strength loss curves for synthetic absorbable sutures follow manufacturer's profile and exceed predicted requirements based on USP for knot strength. | Strength loss curves for synthetic absorbable sutures (Maxon™) follow the profile described in the suture manufacturer's package insert and exceed the predicted strength requirements based on USP requirements for knot strength of synthetic absorbable suture. |
| Biocompatibility/Tissue Reaction (Safety) | No histopathologic change at suture implant sites due to ultrasonic sealing (compared to traditional methods). | No histopathologic change seen at the suture implant sites where the suture was sealed with ultrasonic energy, in both dorsal skin and bowel tissue of New Zealand rabbits. |
| No significant difference in safety/efficacy between traditional suture placement and ASLS. | Investigators concluded there was no significant difference in safety or efficacy between the traditional method of suture placement and the technique which includes replacement of manual knot-tying with suture welding. | |
| Thermal Injury (Safety) | No portion of the ultrasonic generator comes into contact with human tissues, enabling virtually no risk of thermal injury. | "Because of design features of the ASLS, no portion of the ultrasonic generator comes into contact with human tissues. There is virtually no risk of causing a thermal injury to the patient." |
| Sterilization | Sterility Assurance Level (SAL) of at least 10^-6 for gamma irradiation at 2.5 Mrads or 2.0 Mrads (depending on suture type). | Sterilized by exposure to gamma irradiation at 2.5 Mrads (or 2.0 Mrads) which provides a sterility assurance level of at least 10^-6. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the numerical sample size for the test sets in either the in vivo or in vitro studies. It mentions:
- In Vitro Studies: "respective sizes and types of suture materials tested" and "one-week intervals over seven weeks."
- In Vivo Studies: "dorsal skin and in bowel tissue of New Zealand rabbits." This indicates rabbit models were used.
- Data Provenance: The studies were conducted by Axya Medical, Incorporated. The location is not specified, but the submission is to the U.S. FDA, implying the data would be expected to adhere to U.S. regulatory standards. The studies described are prospective as they were conducted specifically to evaluate the ASLS.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document mentions "investigators" who concluded on the safety and efficacy of the in vivo studies. However, it does not specify the number of experts, their qualifications, or how they established the ground truth beyond their conclusions based on histopathologic analysis.
4. Adjudication Method for the Test Set
The document does not describe a formal adjudication method (e.g., 2+1, 3+1). The "investigators" reached conclusions, implying a collegiate or consensus-based approach, but no specific process is detailed.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done
No, an MRMC comparative effectiveness study involving human readers is not described. The study compared the device's performance to conventional knotting or to USP standards.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done
Yes, the studies described are standalone in the sense that they evaluate the performance of the ASLS device itself (suture strength, strength retention, tissue reaction) without a human operator's diagnostic or interpretative input being part of the primary outcome measure. The device replaces manual knot-tying, so its performance is measured against the output of that manual process.
7. The Type of Ground Truth Used
- Suture Strength: Based on USP requirements and comparisons to "conventional knotting techniques."
- Strength Retention: Based on the suture manufacturer's package insert profile and USP requirements.
- Biocompatibility/Tissue Reaction: Established through histopathologic examination of tissue samples from the animal models, with "investigators" providing the conclusions.
- Thermal Injury: Implied from the design features of the device (no tissue contact) and possibly verified by temperature monitoring, though not explicitly detailed.
8. The Sample Size for the Training Set
The document does not mention a training set because this device is a mechanical/energy-based surgical instrument, not an AI/algorithm-based diagnostic system that requires machine learning training.
9. How the Ground Truth for the Training Set Was Established
As there is no mention of a training set, the establishment of ground truth for a training set is not applicable.
§ 878.4800 Manual surgical instrument for general use.
(a)
Identification. A manual surgical instrument for general use is a nonpowered, hand-held, or hand manipulated device, either reusable or disposable, intended to be used in various general surgical procedures. The device includes the applicator, clip applier, biopsy brush, manual dermabrasion brush, scrub brush, cannula, ligature carrier, chisel, clamp, contractor, curette, cutter, dissector, elevator, skin graft expander, file, forceps, gouge, instrument guide, needle guide, hammer, hemostat, amputation hook, ligature passing and knot-tying instrument, knife, mallet, disposable or reusable aspiration and injection needle, disposable or reusable suturing needle, osteotome, pliers, rasp, retainer, retractor, saw, scalpel blade, scalpel handle, one-piece scalpel, snare, spatula, stapler, disposable or reusable stripper, stylet, suturing apparatus for the stomach and intestine, measuring tape, and calipers. A surgical instrument that has specialized uses in a specific medical specialty is classified in separate regulations in parts 868 through 892 of this chapter.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter, subject to the limitations in § 878.9.