(489 days)
The Levita Magnetic Surgical System is designed to grasp and retract the body and the fundus of the gallbladder in laparoscopic cholecystectomy procedures to facilitate access and visualization of the surgical site. The device is indicated for use in patients within a BMI range of 20 to 34 kg/m2.
The Levita Magnetic Surgical System is composed of two hand-held instruments, the Magnetic Grasper Device and external Magnetic Controller, which are intended to facilitate tissue grasping, retraction and mobilization during laparoscopic cholecystectomy procedures.
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Magnetic Grasper Device (sterile, single use) is actuated via its pistol-grip handle with two distinct scissor-type motions to open and close the Detachable Grasper jaws as shown in Figure 1. At the distal end is the Detachable Grasper, which is attached to the Delivery/Retrieval Shaft of the full Magnetic Grasper Device. This device requires a >10mm access port to introduce the device into the abdominal cavity. The Detachable Grasper is then coupled (held in place within the abdomen) by the external Magnetic Controller. If the surgeon wishes to use a single 10-12 mm port at the umbilicus such as a Hasson port and that is the port shared by the optic, applying and adjusting the Detachable Grasper may require repetitive placement of the optic in an alternative port. The Detachable Grasper is shown in Figure 2.
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An External Magnetic Controller (non-sterile, reusable) 3-inch diameter by 2-inch thick b(4) disk magnet, shown in Figure 3. This component holds the Detachable Grasper (magnetically) and is placed on the external abdomen wall.
Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:
Device: Levita Magnetic Surgical System
Indications for Use: To grasp and retract the body and the fundus of the gallbladder in laparoscopic cholecystectomy procedures to facilitate access and visualization of the surgical site, for patients with a BMI range of 20 to 34 kg/m2.
1. Table of Acceptance Criteria and Reported Device Performance
The document outlines various tests with acceptance criteria and results. Here's a consolidated table:
| Category | Specific Test / Performance Characteristic | Acceptance Criteria | Reported Device Performance / Results |
|---|---|---|---|
| Biocompatibility | Cytotoxicity (MEM Elution) | Test Sample Reactivity ≤ 2 | PASS |
| Sensitization (0.9% NaCl, sesame oil) | Test samples < 1 grade dermal reaction | PASS | |
| Irritation/Intracutaneous Reactivity (0.9% NaCl, sesame oil) | Control extract overall mean score ≤ 1.0 | PASS | |
| Shelf Life/Sterility | Detachable Grasper Sterility (Gamma Sterilization) | Sterility Assurance Level (SAL) of 10^-6 | Achieved a SAL of 10^-6 in accordance with ISO 11737-1:2006, ISO 11137-2:2012, and AAMI TIR33:2005. |
| Detachable Grasper Shelf-life visual inspection: outer box damage | No visible damage | PASS | |
| Detachable Grasper Shelf-life visual inspection: outer box label | Label is legible | PASS | |
| Detachable Grasper Shelf-life visual inspection: pouch damage | No visible damage | PASS | |
| Detachable Grasper Shelf-life visual inspection: pouch label | Label is legible | PASS (6-month shelf life determined based on accelerated aging) | |
| EMI/Magnetic Field | Safe Working Distances (Based on ACGIH, ICNIRP, NRC guidelines) | Defined safe zones based on measured magnetic field strength | Magnetic field strength characterized at various distances with and without carrying case; safe working zones defined and detailed in labeling (e.g., 50 cm for pacemakers, 20-50 cm for CRT monitors/magnetic data storage). |
| Bench Performance | Grasper Pull-off force (T=0 & T=6 months) | b(4) CCI/TS (specific value omitted) | PASS for both T=0 and T=6 months. |
| Grasper Pull-off force when near Magnetic Controller (T=0 & T=6 months) | b(4) CCI/TS (specific value omitted) | PASS for both T=0 and T=6 months. | |
| Grasper Jaw Pinch Force (T=0 & T=6 months) | b(4) CCI/TS (specific value omitted) | PASS for both T=0 and T=6 months. | |
| Handle force to open grasper jaws (T=0 & T=6 months) | b(4) CCI/TS (specific value omitted) | PASS for both T=0 and T=6 months. | |
| Minimum grasper jaw opening (T=0 & T=6 months) | b(4) CCI/TS (specific value omitted) | PASS for both T=0 and T=6 months. | |
| Handle force to release grasper jaws (T=0 & T=6 months) | b(4) CCI/TS (specific value omitted) | PASS for both T=0 and T=6 months. | |
| Attraction force to external magnet at a distance of 4 cm (T=0 & T=6 months) | b(4) CCI/TS (specific value omitted) | PASS for both T=0 and T=6 months. | |
| Lifetime Cycling Performance (all above tests) after simulated use and actuations over lifetime | Same as all above | PASS | |
| Magnetic Controller Use Life Testing - Tensile test | Encasement can be suspended by the upper edge b(4) without breakage | PASS (use life of 25 uses determined) | |
| Magnetic Controller Use Life Testing - Visual Inspection | After cycling and suspension, no defects that would compromise integrity | PASS | |
| Animal Study (Safety & Performance) | Safety: Absence of clinically relevant trauma to abdominal wall/tissue (gross & microscopic) | No evidence of clinically relevant trauma. Minimal observations, defects from 5mm trocar more severe than test site. No significant increases in trauma compared to 5mm trocar. | Met. Gross and histopathological findings showed no evidence of clinically relevant trauma. |
| Performance: Ability to manipulate gallbladder & compatibility with instrumentation (single-incision cholecystectomy) | Magnetic Surgical System usable to manipulate gallbladder, able to complete single-incision laparoscopic cholecystectomy, compatible with equipment/instrumentation. | Met. Successfully manipulated gallbladder for several cycles without adverse events; completed a single-incision laparoscopic cholecystectomy; compatible with multiple types of electrosurgical equipment (monopolar, bi-polar, ultrasonic harmonic). | |
| Human Factors | No critical failures (Critical Task Errors) and no more than two non-critical failures per subject | No critical failures and no more than two non-critical failures per subject after training. | All 15 surgeons passed all tests without any critical or non-critical errors. (Critical task errors include: user fails to inspect Magnetic Controller, fails to wipe down/cover Magnetic Controller, inserts Grasper without laparoscopic visualization, attempts to retrieve lost Detachable Grasper using Magnetic Controller, fails to retrieve Detachable Grasper, fails to clean/disinfect Magnetic Controller.) |
| Clinical Study (Safety) | Absence of any damage or side effect to the patient directly produced by the device during surgery (Device Failure and Serious Adverse Events) | 1. No evidence of Device Failure (breakage/malfunction requiring additional surgical intervention, reoperation, device removal). 2. No Serious Adverse Event probably or definitely related to grasping/tissue manipulation or device (revision/removal, permanent organ damage, death). Overall morbidity rate (any complications related to investigational device within 30 days post-op) | Met. No cases of device failure. Three (3) serious adverse events and thirty-five (35) non-serious AEs reported; none were device-related. Twenty (20) device-related events were mild petechiae, considered not clinically significant and resolved. Overall morbidity rate not explicitly quantified but stated as met by absence of serious/device-related AEs. |
| Clinical Study (Performance) | Ability to adequately mobilize the gallbladder to achieve an effective exposure of the target tissue; feasibility will be a "failure" if an additional trocar is needed to insert another instrument to mobilize the gallbladder. | Ability to adequately mobilize the gallbladder to achieve an effective exposure. No additional trocars placed to specifically mobilize the gallbladder. | Met. In all cases, the device was able to adequately mobilize the gallbladder. One additional trocar was placed in one procedure, but after Magnetic Grasper use was complete and not to mobilize the gallbladder. |
Study Details:
2. Sample Size and Data Provenance:
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Test Set (Clinical Study):
- Feasibility Study: 21 subjects underwent surgery.
- Pivotal Study: 50 subjects underwent surgery.
- Total Subjects for Test Set: 71
- Data Provenance: Prospective, single arm, open-label studies conducted in Chile (three sites).
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Animal Study Test Set:
- 2 canines.
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Human Factors Test Set:
- 15 surgeons.
3. Number of Experts and Qualifications for Ground Truth (Test Set):
- Clinical Study: Not explicitly stated as "experts for ground truth determination" in the context of imaging review. The study involved surgeons performing the procedures and evaluating performance and safety, and there were also assessments of safety results by independent groups (e.g., AEs reviewed for device relatedness not explicitly stated if by experts). "Clinical evaluator experienced in single-incision laparoscopy" conducted evaluation in the animal study.
- Animal Study: Safety evaluated grossly by a pathologist and microscopically by an independent histopathologist. Performance evaluated by a clinical evaluator experienced in single-incision laparoscopy.
- Human Factors Study: The "ground truth" for task completion and errors was established by experienced proctors/observers during the simulated use environment, implicitly serving as experts.
4. Adjudication Method for the Test Set:
- Clinical Study: Not explicitly mentioned as a formal adjudication method (e.g., 2+1, 3+1 for imaging). Safety endpoints (device failure, serious adverse events) were defined and assessed. Device-related events (mild petechiae) were "not considered clinically significant by the study investigators."
- Animal Study: Gross pathological findings by one pathologist, microscopic by an independent histopathologist, and clinical evaluation by an experienced laparoscopist. This implies a form of expert review, though not a multi-reader, consensus-based adjudication as typically seen in image-based AI studies.
- Human Factors Study: Based on observation of 15 surgeons completing tasks against predefined critical and non-critical error lists during simulated use. The "acceptance criteria were no critical failures... and no more than two non-critical failures per subject." This is a pass/fail assessment based on observed performance against a checklist.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- No, an MRMC comparative effectiveness study was not done.
- The clinical study was a single-arm study, meaning there was no control group of traditional laparoscopic cholecystectomy without the device for direct comparison of outcomes or human reader (surgeon) performance improvement.
- The document explicitly states: "Since the studies presented were single armed, comparisons could not be made due to lack of a traditional laparoscopic cholecystectomy control." Therefore, no effect size of human readers improving with AI vs. without AI assistance can be reported. The device is a surgical instrument, not an AI for image interpretation.
6. Standalone (Algorithm only without human-in-the-loop performance):
- This question is not applicable as the Levita Magnetic Surgical System is a medical device (a surgical instrument), not an AI algorithm. Its performance is intrinsically linked to human use (the surgeon). The "performance testing" described in the document (bench, animal, clinical) evaluates the device's functional integrity and its performance when operated by a human user.
7. Type of Ground Truth Used:
- Clinical Study:
- Safety: Clinical endpoints observed during surgery and post-operative follow-up, assessed by study investigators (e.g., device failures, serious adverse events, morbidity, petechiae).
- Performance: Surgeon assessment of the ability to mobilize the gallbladder and completion of the cholecystectomy procedure.
- Patient Outcomes: Patient surveys, operative time, PACU time, length of stay, pain scores, blood loss, etc.
- Animal Study: Gross pathological findings, microscopic histopathological findings, and clinical evaluation by an experienced surgeon.
- Human Factors Study: Direct observation of task completion and identification of predefined critical/non-critical errors by trained proctors in a simulated environment.
8. Sample Size for the Training Set:
- Not explicitly stated for an AI model. As this is a medical device (surgical instrument), not an AI, there isn't a "training set" in the context of machine learning model development.
- However, if "training set" refers to the subjects or data used to train the human users of the device:
- Human Factors Study: 15 surgeons received training materials (Instructions for Use, labels, screening checklist, didactic presentation, hands-on demonstration) before being tested. This served as their "training."
9. How the Ground Truth for the Training Set was Established:
- Not applicable in the context of an AI training set for model development.
- For the human factors training, the "ground truth" for proper use was established by the manufacturer through the development of the Instructions for Use, training presentation, and a pre-defined list of correct (and incorrect) operational steps/critical tasks. This represents the manufacturer's validated understanding of safe and effective device operation.
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DE NOVO CLASSIFICATION REQUEST FOR LEVITA MAGNETIC SURGICAL SYSTEM
REGULATORY INFORMATION
FDA identifies this generic type of device as:
Magnetic Surgical Instrument System. A magnetic surgical instrument system is a prescription device used in laparoscopic surgical procedures consisting of several components, such as surgical instruments, and a magnetic controller. The magnetic controller is provided separately from the surgical instrument and is used outside the patient. The external magnetic controller is magnetically coupled with the internal surgical instrument(s) at the surgical site to grasp, hold, retract, mobilize or manipulate soft tissue and organs.
NEW REGULATION NUMBER: 21 CFR 878.4815
CLASSIFICATION: II
PRODUCT CODE: PNL
BACKGROUND
DEVICE NAME: LEVITA MAGNETIC SURGICAL SYSTEM
SUBMISSION NUMBER: DEN150007
DATE OF DE NOVO: FEBRUARY 10, 2015
LEVITA MAGNETICS INTERNATIONAL CORP. CONTACT: 1430 S. AMPHLETT BLVD, SUITE 240 SAN MATEO, CA 94402
REQUESTER'S RECOMMENDED CLASSIFICATION: II
INDICATIONS FOR USE
The Levita Magnetic Surgical System is designed to grasp and retract the body and the fundus of the gallbladder in laparoscopic cholecystectomy procedures to facilitate access and visualization of the surgical site. The device is indicated for use in patients within a BMI range of 20 to 34 kg/m2.
LIMITATIONS
The sale, distribution, and use of the Levita Magnetic Surgical System are restricted to prescription use in accordance with 21 CFR 801.109.
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Limitations on device use are also achieved through the following statements included in the instructions for use:
Contraindications:
- Do not use on patients or near anyone with pacemakers, defibrillators, or other ● electromedical implants.
- Do not use on patients or near anyone with ferromagnetic implants. .
Warnings and Precautions:
Failure to adhere to the instructions below may result in patient or user injury and/or damage to the device.
- Do not use on patients or near anyone who does not pass the Magnetic Surgery . Screening Checklist. A screening checklist is provided by Levita Magnetics for this purpose.
- Do not use the Magnetic Controller to attempt to retrieve a lost Detachable . Grasper. Doing so could result in significant patient harm, including significant damage to tissue and/or vasculature.
- . The Magnetic Controller contains a strong magnet. Safe working zones have been defined for the Magnetic Controller. Adhere to the safe zones described in the following tables, and maintain a safe working distance. Failure to adhere to the safety zones may result in patient and/or user injury.
| Safe Zones for Magnetic Controller | Safe Working Distance. Do not positioncloser than distance specified. |
|---|---|
| Outside of Carrying Case Category | |
| Personnel/patients with cardiac pacemakers,or medical implants | 50 cm (20 inches) |
| Equipment with cathode-ray tubes (i.e. CRTmonitors) | 50 cm (20 inches) |
| Equipment with magnetic data storage | 50 cm (20 inches) |
| Small ferromagnetic objects | 25 cm (10 inches) |
| General electrical equipment | 25 cm (10 inches) |
| Safe Zones for Magnetic Controller Insideof Carrying Case Category | Safe Working Distance. Do not positioncloser than distance specified. |
|---|---|
| Personnel/patients with cardiac pacemakers,or medical implants | 50 cm (20 inches) |
| Equipment with cathode-ray tubes (i.e. CRTmonitors) | 50 cm (20 inches) |
| Equipment with magnetic data storage | 20 cm (8 inches) |
| Small ferromagnetic objects | 5 cm (2 inches) |
| General electrical equipment | 5 cm (2 inches) |
- Place the manufacturer-supplied safety signage on all entry doors of the operating ● room.
- The safety and effectiveness of the Magnetic Surgical System for use in patients ● with BMI <20 or >34 has not been established.
- Assess the gallbladder and do not use the Magnetic Surgical System if adhesions, ● stones, or fibrosis interfere with exposure of the critical view of safety or
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definition of the components of the hepatocystic triangle.
- . When the Detachable Grasper is detached from the gallbladder, reestablishing attachment requires a greater number of steps and may be more time consuming than with a shafted (i.e., traditional) grasper.
- Placement of an additional trocar port may be required if exposure is inadequate . and/or additional treatment is needed after complete removal of the gallbladder from the hepatic bed.
- . The Magnetic Grasper Device should be used to grasp only the fundus or the body of the gallbladder.
- The Magnetic Grasper Device is for single use only. Do not resterilize or reuse.
- . Do not use multiple Magnetic Controllers simultaneously.
- Inability to adequately grasp, retract and /or mobilize target tissue using the Magnetic Surgical System during the procedure may require the use of an additional trocar to complete the surgery.
- . Always store the Magnetic Controller in the manufacturer-supplied carrying case.
PLEASE REFER TO THE LABELING FOR A MORE COMPLETE LIST OF WARNINGS, PRECAUTIONS AND CONTRAINDICATIONS.
DEVICE DESCRIPTION
The Levita Magnetic Surgical System is composed of two hand-held instruments, the Magnetic Grasper Device and external Magnetic Controller, which are intended to facilitate tissue grasping, retraction and mobilization during laparoscopic cholecystectomy procedures.
-
- Magnetic Grasper Device (sterile, single use) is actuated via its pistol-grip handle with two distinct scissor-type motions to open and close the Detachable Grasper jaws as shown in Figure 1. At the distal end is the Detachable Grasper, which is attached to the Delivery/Retrieval Shaft of the full Magnetic Grasper Device. This device requires a >10mm access port to introduce the device into the abdominal cavity. The Detachable Grasper is then coupled (held in place within the abdomen) by the external Magnetic Controller. If the surgeon wishes to use a single 10-12 mm port at the umbilicus such as a Hasson port and that is the port shared by the optic, applying and adjusting the Detachable Grasper may require repetitive placement of the optic in an alternative port. The Detachable Grasper is shown in Figure 2.
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Image /page/3/Figure/0 description: This image shows a magnetic grasper device with labels and measurements. The device has four labeled parts: the delivery/retrieval shaft (1), the detachable grasper (2), the jaws (3), and the handle (4). The delivery/retrieval shaft is 47 cm long, the detachable grasper is 6.5 cm long, and the handle is 10 cm long.
Image /page/3/Figure/1 description: In the image, a detailed view of a surgical instrument is presented, showcasing its various components. The instrument features a "Jaw Base", a "Jaw Actuator", and a "Jaw Pin". Additionally, "Torsion Springs" are visible, contributing to the instrument's functionality.
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- An External Magnetic Controller (non-sterile, reusable) 3-inch diameter by 2-inch thick b(4) disk magnet, shown in Figure 3. This component holds the
Detachable Grasper (magnetically) and is placed on the external abdomen wall.
- An External Magnetic Controller (non-sterile, reusable) 3-inch diameter by 2-inch thick b(4) disk magnet, shown in Figure 3. This component holds the
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Surface field strength of b(4) Gauss within an encasement with integrated handles. Static ● field and does not induce current flow.
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. Mounting stem for optionally attaching it to a commercially available surgical support arm.
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Comprised of ferromagnetic material If the External Magnetic Controller is moved . within a short distance of the interior abdominal wall, it can act on the internally placed Detachable Grasper, pulling it toward the abdominal wall.
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The user varies the distance required to achieve the necessary attraction between the Detachable Grasper and Magnetic Controller during the procedure.
Image /page/3/Picture/9 description: The image shows a gray object with two handles and an arm mount. The handles are located on either side of the object, and the arm mount is located on the top. The object appears to be made of plastic. The handles are curved and the arm mount is cylindrical.
Figure 3 – External Magnetic Controller
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SUMMARY OF NONCLINICAL/BENCH STUDIES
BIOCOMPATIBILITY/MATERIALS
Biocompatibility testing was not conducted on the Magnetic Controller because it is not patient-contacting. It is a noncritical reusable device because it is placed in a sterile bag or covered with a drape during use and does not have direct contact with the patient's skin.
Biocompatibility testing was conducted on the Magnetic Grasper Device in accordance with the FDA's modified matrix Blue Book Memorandum #G95-1, entitled Use of International Standard ISO 10993-1, Biological Evaluation of Medical Devices, Part 1 Evaluation and Testing within a risk management process. The tests were performed on the patient-contacting materials identified in Table 1 below. As seen in Table 2, the tests performed included cytotoxicity, sensitization, and irritation.
Table 1: Patient Contacting Materials
| Components | Materials | |
|---|---|---|
| Torsion Springs | b(4) | Stainless Steel |
| Top Jaw | b(4) | Stainless Steel |
| Jaw Actuator, Jaw Pin, Shaft, Distal Taper,Actuation Rod, Magnet Puller | b(4) | Stainless Steel |
| Jaw Base | b(4) | Stainless Steel |
| Cup Tip, Magnet Stop | b(4) | Stainless Steel |
Table 2: Biocompatability Tests
| Biocompatibility Test | Standard | Acceptance Criteria | Results |
|---|---|---|---|
| Cytotoxicity (MEMElution) | ISO 10993-5 | Test Sample Reactivity $\leq$ 2 | PASS |
| Sensitization (0.9% NaCl,sesame oil) | ISO 10993-10 | Test samples $<$ 1 grade dermal reaction | PASS |
| Irritation/IntracutaneousReactivity (0.9% NaCl,sesame oil) | ISO 10993-10 | Control extract overall mean score $\leq$ 1.0 | PASS |
SHELF LIFE/STERILITY
The detachable grasper component of the Levita Magnetic Surgical System is provided sterile and is single use. The device is sterilized by gamma sterilization process with a dose of 27.5 kGy to 40 kGy, which achieves a sterility assurance level (SAL) of 10 ° and is performed in accordance with the following standards:
Table 3: Detachable Grasper Sterilization Testing Standards
| Standards | Results |
|---|---|
| ISO 11737-1:2006 Sterilization of health care products –Radiation - Part 1: Requirements for development,validation and routine control of a sterilization processfor medical devices | PASS |
| ISO 11137-2: 2012 Sterilization of health care products –Radiation – Part 2: Establishing the sterilization dose | PASS |
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| Standards | Results |
|---|---|
| AAMI TIR33:2005 Sterilization of health care products-Radiation -Substantiation of a selected sterilization dose -Method b(4) | PASS |
The second component, the Magnetic Controller, is a reusable component of the Magnetic Surgical System and is provided non-sterile. It is a noncritical reusable device because it is placed in a sterile bag or covered with a drape during use and does not have direct contact with the patient's skin. The Magnetic Controller is cleaned and then receives intermediate level disinfection prior to reuse on another patient.
Shelf life for the detachable gasper was determined to be 6 months based on accelerated aging, as demonstrated in Table 4 and the design verification tests summarized in Table 8 in the PERFORMANCE TESTING - BENCH section below.
| Test | Acceptance criteria | Results |
|---|---|---|
| Shelf-life visual inspection: outerbox damage | No visible damage | PASS |
| Shelf-life visual inspection: outerbox label | Label is legible | PASS |
| Shelf-life visual inspection: pouchdamage | No visible damage | PASS |
| Shelf-life visual inspection: pouchlabel | Label is legible | PASS |
Table 4: Detachable Grasper Shelf Life Testing
ELECTROMAGNETIC COMPATIBILITY AND ELECTRICAL SAFETY
There are no electrical components in the Levita Magnetic Surgical System; therefore electrical safety and compatibility testing are not applicable. However, as a magnetic system, magnetic field strength testing was provided to determine the safe working zones for the Magnetic Controller and to address the risk of magnetic field interference with electromedical equipment and ferromagnetic instruments and implants.
The strength of the static magnetic field was measured at distances of b(4) . and bb(4) from the face of the magnet b(4) , with and without the carrying case. By determining the magnetic field strength at several distances, the safe working zones for use of the device were determined. Safe zones were defined based on the characterization data compared with guidelines established in publications by the American Conference of Industrial Hygienists (ACGIH), the International Commission on Non-ionizing Radiation Protection, and the National Research Council (NRC) regarding occupational safety and laboratory practices and safe general public exposure. The summary of the results can be found in the following tables (Tables 5 and 6):
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| Measured Magnetic Field Strength | |
|---|---|
| Max. Magnetic flux @b(4) on 3 samples | b(4) |
| Min. Magnetic flux @b(4) on 3 samples | b(4) |
| Average | 15.15 G |
| Standard Deviation | 13.85 G |
| Max. Magnetic flux @b(4) on 3 samples | b(4) |
| Min. Magnetic flux @b(4) on 3 samples | b(4) |
| Average | 4.25 G |
| Standard Deviation | 3.75 G |
| Max. Magnetic flux @b(4) on 3 samples | b(4) |
| Min. Magnetic flux @b(4) on 3 samples | b(4) |
| Average | 3.45 G |
| Standard Deviation | 0.25 G |
Table 5: Test Data with External Magnetic Controller In Case
Table 6: Test Data with External Magnetic Controller Outside Case
| Measured Magnetic Field Strength | ||
|---|---|---|
| Max. Magnetic flux @b(4) | on 3 samples | b(4) |
| Min. Magnetic flux @b(4) | on 3 samples | b(4) G |
| Average | 18.25 G | |
| Standard Deviation | 2.45 G | |
| Max. Magnetic flux @b(4) | on 3 samples | b(4) |
| Min. Magnetic flux @b(4) | on 3 samples | b(4) |
| Average | 2.95 G | |
| Standard Deviation | 0.55 G | |
| Max. Magnetic flux b(4) | cm on 3 samples | b(4) |
| Min. Magnetic flux b(4) | on 3 samples | b(4) G |
| Average | 1.45 G | |
| Standard Deviation | 0.65 G |
PERFORMANCE TESTING – BENCH
Testing was performed to verify the device design. Performance criteria were evaluated by conducting mechanical testing intended to show both functional performance and mechanical integrity. The design verification testing included evaluations to address performance characteristics that would be affected by aging. Specifically, the functional verification testing included force testing to be assured of the device ability to perform the desired functions, such as grasping the tissue (Table 7). The sponsor also tested how the forces would be affected after accelerated aging to 6 months (Table 8).
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| Test | AcceptanceCriteria | Results |
|---|---|---|
| Grasper Pull-off force | b(4) CCI/TS | PASS |
| Grasper Pull-off force when near Magnetic Controller | PASS | |
| Grasper Jaw Pinch Force | PASS | |
| Handle force to open grasper jaws | PASS | |
| Minimum grasper jaw opening | PASS | |
| Handle force to release grasper jaws | PASS | |
| Attraction force to external magnet at a distance of 4 cm | PASS | |
| Lifetime Cycling Performance (all above tests) aftersimulated use and actuations over lifetime | Same as allabove | PASS |
Table 7: Device Design Verification Testing: Functional (T = 0 months)
Table 8: Device Design Verification Testing: Functional (T = 6 months)
| Test | AcceptanceCriteria | Results |
|---|---|---|
| Grasper Pull-off force | b(4) CCI/TS | PASS |
| Grasper Pull-off force when near Magnetic Controller | PASS | |
| Grasper Jaw Pinch Force | PASS | |
| Handle force to open grasper jaws | PASS | |
| Minimum grasper jaw opening | PASS | |
| Handle force to release grasper jaws | PASS | |
| Attraction force to external magnet at a distance of 4 cm | PASS |
In addition, for the external magnetic controller, the use life was determined to be 25 uses based on accelerated aging, as demonstrated in Table 9 below.
Table 9: Magnetic Controller Use Life Testing
| Magnetic Controller Use LifeTesting after 25 Uses | Acceptance Criteria | Results |
|---|---|---|
| Tensile test | Encasement can be suspended by the upper edge b(4) without breakage | PASS |
| Visual Inspection | After cycling and suspension, no defects that would compromise integrity | PASS |
Bench testing demonstrated that the device performs as expected under anticipated conditions of use.
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PERFORMANCE TESTING – ANIMAL
As described in detail in Table 9, an animal study was conducted to support that the Levita Magnetic Surgical System performs as expected under anticipated use conditions.
| Title: | Levita Magnetic Surgical System Animal Safety and Performance Study |
|---|---|
| Study Objective: | Evaluate the effects of the Magnetic Surgical System when used in thin-abdominal wall subjects, specifically when using the Magnetic Controller to change position of the Detachable Grasper for purposes of tissue manipulation when the Magnetic Controller and the Detachable Grasper are both in contact with the abdominal wall; Evaluate the performance of the Magnetic Surgical System when used during single-incision laparoscopic cholecystectomy surgery; Evaluate the Magnetic Surgical System's compatibility with laparoscopic instrumentation and operating room equipment, specifically monopolar, bi-polar and ultrasonic harmonic instrumentation |
| Study Endpoints: | Safety was assessed by evaluation of the effects of the Magnetic Surgical System on the abdominal wall and abdominal tissue/organs. The effects were determined grossly by a pathologist and microscopically by an independent histopathologist. Performance was assessed by the evaluation of the Magnetic Surgical System when used in single incision laparoscopic cholecystectomy, compatibility of the Magnetic Surgical System with the instrumentation and equipment used during the procedure, and ability to retrieve the Detachable Grasper. A clinical evaluator experienced in single-incision laparoscopy conducted the evaluation. |
| Study Design: | Two canines underwent a single-port laparoscopic cholecystectomy procedure; an intentional maximum force repeated dragging of the Detachable Grasper over a section of abdominal wall, and an intentional dropping and retrieval of the Detachable Grasper into and from the abdominal cavity. To assess their compatibility, multiple types of electrosurgical equipment were used during the laparoscopic cholecystectomy.Canines were chosen for their abdominal wall thickness, which represents worst-case (thin) human abdominal walls of 0.5cm to 1.0cm. The minimum human abdominal wall thicknesses in the published study referenced above were 5mm and 10mm, for the umbilicus and left upper quadrant, respectively. |
Table 10: In Vivo Animal Study
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| Results: | The Magnetic Surgical System was utilized to manipulate the gallbladder forseveral cycles using the Magnetic Controller, without any adverse events. Thesponsor states that their experience with the Magnetic Surgical System in this studysuggests the ability to control the devices within the abdominal cavity using amagnet external to the body. The sponsor also states that based on user feedbackthere is the ability to have minor haptic feel without controlling the internal devicevia a shaft. This haptic feel is limited to drag sensation when retracting the body orfundus of the gallbladder with the external magnet while coupled to internaldetachable grasper. The minor haptic feel does not provide feedback in regards tothe changes in the grasping of gallbladder tissue with manipulation of thegallbladder and progress of the surgery. |
|---|---|
| The gross pathological findings demonstrated that there was no evidence ofclinically relevant trauma to the abdominal wall associated with the test articles.The observations noted were minimal and the defects caused by the control 5mmtrocar were much more severe as compared to the test site. The findings resultingfrom the placement of a 5mm trocar typically used in laparoscopic proceduresdemonstrate obvious full body wall thickness trauma, including hemorrhage.Moreover, the histopathological findings demonstrate that there were no significantincreases in trauma associated with the test article when compared to a 5mm trocar. | |
| The safety endpoint acceptance criteria for intra-procedural adverse events, grosspathology, and histopathology evaluation were met. | |
| In the performance evaluation, the Magnetic Surgical System was employed tocomplete a single-incision laparoscopic cholecystectomy. The performanceendpoint acceptance criteria for the completion of a laparoscopic cholecystectomyand compatibility with equipment/instrumentation were met. | |
| In summary, all study objectives were successfully met. |
PERFORMANCE TESTING - HUMAN FACTORS
The sponsor conducted human factors validation testing using a training didactic presentation prior to testing the participants, 15 surgeons at 2 different sites. Simulated use environment testing was used to assess the effectiveness of the proposed commercial training program and if it facilitates safe use of the device. Simulated use environment was used since it is possible to engage more users in more use scenarios in a limited amount of time as compared to a clinical study.
The sponsor trained the surgeons using the Instructions for Use, device labels, patient screening checklist, and a training presentation. All subjects were trained face-to-face using the training presentation and the hands-on demonstration described in the presentation. The sponsor has developed a training didactic presentation that follows the Instructions for Use to train for correct use of the system. The training presentation includes sections on safe use of the device, contraindications, warnings, precautions, potential adverse events, patient selection, instructions for use, and hands-on practice. Training groups consisted of 3-4 test subjects and they completed all aspects of the study, including the pre-simulation questionnaire, all three scenarios of the simulation, and the post-simulation questionnaire. The acceptance criteria were no critical failures (Critical
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Task Errors detailed below in Table 8) and no more than two non-critical failures per subject (any failures with the tasks written below not indicated as critical tasks). Tasks performed after reading the User Manual and Training during the Human Factors assessment included:
- User removes Magnetic Grasper Device from packaging places in sterile field ●
- . User performs inspection of Magnetic Grasper Device functionality
- . User removes Magnetic Controller from case
- User performs inspection of Magnetic Controller (critical task) ●
- User wipes down Magnetic Controller (critical task)
- User covers Magnetic Controller with sterile bag (critical task)
- . User inserts Magentic Grasper Device into 100 mm or larger port under laparoscopic visualization (critical task)
- User advances and maneuvers Magnetic Grasper Device towards tissue .
- User opens Magnetic Grasper jaws by retracting handle thumb lever ●
- User engages tissue with open Magnetic Grasper jaws ●
- User closes Magnetic Grasper jaws upon tissue by advancing handle thumb lever ● to default position
- User decouples Detachable Grasper from Delivery/Retrieval Shaft of the Magnetic Grasper Device by advancing handle thumb lever to forward position
- User moves Magnetic Controller to abdominal area to attract Detachable Grasper towards abdominal wall
- . User positions Magnetic Controller at distance from abdomen to result in "Acceptable Contact" of the Detachable Grasper with the abdominal wall
- . User adjusts Magnetic Controller's position to appropriately lift and retract the tissue
- . In the event of unintended decoupling of the Detachable Grasper from the Magnetic Controller, user recouples the Detachable Grasper to the Magnetic Controller using appropriate instruments
- In the event of a lost or hidden Detachable Grasper, user retrieves Detachable . Grasper with appropriate instruments (critical task)
- User retrieves Detachable Grasper and removes Detachable Grasper from ● abdomen through port (critical task)
- User removes sterile bag from Magnetic Controller and cleans/disinfects . Magnetic Controller (critical task)
- . User disengages Magnetic Controller from optional off-the-shelf positioning arm and returns Magnetic Controller to carrying case
- . User returns Magnetic Controller to storage
The following table (Table 11) identifies the possible device use-related hazards due to the critical tasks (indicated above) and their respective mitigations.
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| Critical Task Error | Hazard(s) Resulting from Error | Severity | Mitigations |
|---|---|---|---|
| User fails to perform inspection of Magnetic Controller | Malfunctioning device used in procedure, injury to patient or user | 3 | Inspection instructions in IFU Physician Training |
| User fails to wipe down Magnetic Controller | Contamination | 4 | Device preparation instructions in IFU Warnings and Precautions in IFU Physician Training |
| User fails to cover Magnetic Controller with sterile bag | Infection | 4 | Device preparation instructions in IFU Physician Training |
| User inserts Grasper without laparoscopic visualization | Intra-abdominal tissue trauma | 3 | Instructions on device insertion in IFU Warnings and Precautions in IFU Physician Training |
| In the event of a lost or hidden Detachable Grasper, user attempts to retrieve Detachable Grasper using Magnetic Controller | Tissue trauma/injury | 4 | Instructions on retrieval in IFU Warning statement in IFU Physician Training |
| User fails or is unable to retrieve Detachable Grasper and remove from abdomen through port | Tissue trauma Injury from larger incision | 3 | Retrieval and removal instructions in IFU Physician Training |
| User fails to clean/disinfect Magnetic Controller | Infection | 4 | Cleaning/Disinfection instructions in IFU Physician Training |
This Human Factors study assessed the ability of surgeons to operate the Magnetic Surgical System after training with no critical errors and no more than two non-critical errors after participating in a training regarding these devices. All 15 test subjects passed all tests without any critical or non-critical errors.
SUMMARY OF CLINICAL INFORMATION
As described in detail in Table 12, a clinical study was conducted to support that the Levita Magnetic Surgical System performs as expected under anticipated use conditions.
| Title: | Levita Magnetic Surgical System Safety and Performance Study |
|---|---|
| Study Objective: | The first study was to evaluate the preliminary safety and feasibility of the LevitaMagnetic Surgical System in the treatment of patients undergoing laparoscopiccholecystectomy for benign gallbladder diseaseSecond study was a pivotal study to evaluate safety and effectiveness of the LevitaMagnetic Surgical System in the treatment of patients undergoing laparoscopiccholecystectomy for benign gallbladder disease |
| Study Design: | Prospective, single arm, open label study (both feasibility and pivotal) designed toassess the safety and device performance of the Levita Magnetic Surgical System.All patients were expected to undergo post-operative pain evaluation, cosmesis,and quality of life assessments. Appearance of the post-operative scar and patientsoverall satisfaction with the procedure were evaluated. |
| Enrollment Size andNumber of Sites: | Levita performed their feasibility study with 21 patients and had a second single-armedpivotal study with 50 patients conducted in three (3) sites in Chile |
| Patient Population: | All patients between 18 and 60 yrs of age, presenting with benign gallbladder diseasewho are eligible for laparoscopic cholecystectomy were potential candidates |
| Number of Subjects | Feasibility Study: 22 enrolled, 21 subjects underwent surgeryPivotal Study: 50 subjects underwent surgery |
| Primary SafetyEndpoints: | Absence of any damage or side effect to the patient directly produced by the deviceduring the surgery defined as:1. There is no evidence of a Device Failure defined as device breakage or othermalfunction requiring additional surgical intervention including reoperationand/or device removal.2. There is no Serious Adverse Event probably or definitely related to thegrasping and tissue manipulation procedure or to the device resulting in: (a)revision/removal of device; and/or (b) permanent damage to the organ (i.e.perforation of the gallbladder or surrounding organs), (c) death of the studysubject.Overall morbidity rate defined as occurrence of any complications directly orindirectly related to the investigational device assessed intra-operatively, post-operatively and at 30 day follow-up occurring within 30 days of surgery. |
| Primary FeasibilityEndpoint: | Ability to adequately mobilize the gallbladder to achieve an effective exposure of thetarget tissue.*Feasibility will be considered a "failure" if during the procedure, it becomes necessaryto use another trocar to insert another instrument to mobilize the gallbladder. |
| Other OutcomeAssessments: | Operative time (time from the first incision to the last suture's placement) Device use time (time of coupling between the internal grasper and theexternal magnetic controller) Time spent in Post-anesthesia care unit (PACU) Length of stay (LOS) (time from post-anesthesia care unit until discharge) Perioperative pain as measured on a Numeric Rating Scale (NRS) at pre-op(baseline), 3 and 6 hours post-op and discharge (24 hour post-op assessmentwill be done if patient is not discharged) and at 7 and 30 day follow-up Pain medication usage while in PACU and until hospital discharge Conversion rate (reduced port to 4-port) Blood loss Umbilical incisional length Access site herniation Patient satisfaction with the overall procedure based on patient survey at 30day follow-up Ease of use based on surgeon assessment post-operatively Cosmesis or scarring (patient and surgeon assessed satisfaction survey) at 7and 30 day follow-up Final post-operative diagnosis |
| Inclusion Criteria: | Patient between 18 and 60 years of age Undergoing elective cholecystectomy due to: Cholelithiasis (Gallbladder stones < 2.5cm in longer measurement(length or width)) |
| Gallbladder polyps as assessed by ultrasound Absence of non-correctable coagulopathy (INR < 1.4 or, platelet count of < 50,000/mcl) Patient has a body mass index (BMI) ≤ 34 kg/m² and over 20 kg/m² Patient, or authorized representative, signs a written Informed Consent form to participate in the study, prior to any study mandated determinations or procedure | |
| Exclusion Criteria: | Emergency presentation with acute gallbladder disease Clinical suspicious of Pancreatitis Jaundice Scleroatrophic gallbladder as shown by ultrasound Biliary tract stones diagnosed before or during surgery Acute cholecystitis Gallbladder Empyema Ongoing peritoneal dialysis Previous abdominal surgery or laparotomy (presence of any previous upper umbilical incision) Presence of umbilical hernia or previous umbilical hernia American Society of Anesthesiologists (ASA) score of III or IV Patient is undergoing treatment for chronic pain of any origin Significant comorbidities: cardiovascular, neuromuscular, chronic obstructive pulmonary disease, and urological disease (renal failure) Patients with signs of gallbladder perforation diagnosed by ultrasound Suspicion of biliary cancer Patients with severe peritonitis Contraindications to pneumoperitoneum Known allergy to paracetamol or NSAIDs Patients with metallic implants (such as pacemakers, prosthesis, etc) Previously diagnosed or suspected of having a history of choledocholithiasis based on any alterations in plasma hepatic enzymes Has a biliary tract > 7mm in size as determined by ultrasound Has a gallbladder wall thickness that is > 5mm Diabetic Blood coagulation issues Has signs of hepatic endocrinology (i.e: cirrhosis, liver failure, increase in liver enzymes, etc.) History of endoscopic papillotomy (i.e: Preoperative indication of endoscopic retrograde cholangiopancreatography (ERCP) Patient is pregnant or wishes to become pregnant during the length of study participation or lactation Patient is not likely to comply with the follow-up evaluation schedule Patient is participating in a clinical trial of another investigational drug or device |
| Known or suspected drug or alcohol abuse Patient has systemic infection or evidence of any surgical site infection (superficial or organ space) Patient has compromised immune system or autoimmune disease (WBC < 4000 or > 20,000), including prior or pending treatment for HIV or Hep. C Patient intra-operatively needs an additional surgery while undergoing elective cholecystectomy | |
| Study Duration / Follow-up Period | Patients were followed for a maximum of 30 days post-procedure, with follow-up visits at hospital discharge and at 7 and 30 days post-procedure. |
Table 12: Clinical Study Data
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Results:
The safety results met the criteria outlined for the primary safety endpoint for this study, because there were no cases of a device failure. Device failure is defined as device breakage or other malfunction requiring additional surgical intervention including reoperation and/or device removal. Three (3) serious adverse events and thirty-five (35) non serious AEs were reported throughout the course of the study. No severe or serious adverse events were found to be devicerelated. Twenty (20) device-related events were noted. The device-related events were categorized as mild petechiae that were observed during the index procedure. The observed petechiae were mild and were not considered clinically significant by the study investigators, as all events resolved with no clinical sequelae. The mild petechiae reported represent much less trauma to the tissue than would be the case with a trocar insertion. This is a single arm study and patient survey indicated that over 90% of the patients were satisfied on postoperative day 7 and 30.
The device performance results met the criteria outlined for the primary performance endpoint for this study, because in all cases the device was able to adequately mobilize the gallbladder to achieve an effective exposure of the target tissue. While an additional trocar was placed in one procedure, this additional trocar was not needed to mobilize the gallbladder and this trocar was placed after the Magnetic Grasper device use was complete and removed from the abdomen. As a result, no additional trocars were placed to insert another instrument to mobilize the gallbladder.
The results show that the Magnetic Surgical System can be used in laparoscopic cholecystectomy procedures in subjects with varying abdominal wall thicknesses (1.8 – 4.6 cm) that correspond with a range of BMIs (20.4 – 34.1 kg/m2). Additionally, the device can be used to facilitate three-port cholecystectomy procedures in a manner that provides adequate exposure and mobilization of the target tissue. The average overall procedure time was 63 minutes and the amount of coupling time between the Magnetic Controller and the Magnetic Detachable Grasper was 34 minutes. All procedures were completed with no conversions to an open surgical approach required. Importantly, the Magnetic Surgical System was used in a standard operating room with conventional electrosurgical equipment and no device malfunctions or equipment interferences were reported.
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LABELING
Labeling has been provided, which includes the instructions for use and an appropriate prescription statement as required by 21 CFR 801.109.
The sponsor has provided the magnetic field strength testing results, including tables detailing the magnetic safe zones, in the User Manual and on the external magnetic controller carrying case. In addition, the sponsor has included a Screening Checklist to ensure that all patients and Operating Staff are screened from bringing ferromagnetic implants, devices or objects near the external magnet. These magnetic safe zones tables and the Screening Checklist mitigate the risk of electromagnetic field incompatibility or interference.
The sponsor has provided detailed instructions for proper device use, which mitigate the risks of tissue damage, need for extended or additional surgery, abdominal wall injury, and electromagnetic field incompatibility or interference.
The sponsor has included sterilization, cleaning and disinfection instructions, along with determined shelf life, which mitigate the risk of infection.
RISKS TO HEALTH
Table 13 identifies the risks to health that may be associated with use of the Magnetic Surgical Instrument System and the measures necessary to mitigate these risks.
| Identified Risk | Mitigation Measures |
|---|---|
| Tissue Damage | In vivo Performance Testing Human Factors Testing and Analysis Training Labeling |
| Need for Extended or Additional Surgery:Inability to couple the external magnet with the internal surgical instrument Inability to retrieve or maneuver device Inability to visualize critical anatomical structures | In vivo Performance Testing Non-clinical Performance Testing Human Factors Testing and Analysis Training Labeling |
| Abdominal Wall Injury | In vivo Performance Testing Human Factors Testing and Analysis Labeling |
| Electromagnetic Field Incompatibility or Interference (including ferromagnetic implants in users and patients, electrosurgical devices, etc.) | Non-clinical Performance Testing Human Factors Testing and Analysis Training Labeling |
| Adverse Tissue Reaction | Biocompatibility Evaluation |
Table 13: Identified Risks to Health and Mitigation Measures
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| Identified Risk | Mitigation Measures |
|---|---|
| Infection | • Sterilization Validation |
| • Reprocessing Validation | |
| • Shelf Life Validation | |
| • Labeling |
SPECIAL CONTROLS:
In combination with the general controls of the FD&C Act, the Magnetic Surgical Instrument System is subject to the following special controls:
- (1) In vivo performance data must demonstrate that the device performs as intended under anticipated conditions of use. Testing must demonstrate the ability of the device to grasp. hold, retract, mobilize or manipulate soft tissue and organs.
- (2) Non-clinical performance data must demonstrate that the system performs as intended under anticipated conditions of use. The following performance characteristics must be tested:
- (a) Magnetic field strength testing characterization to identify the distances from the magnet that are safe for patients and users with ferromagnetic implants, devices or objects.
- (b) Ability of the internal surgical instrument(s) to be coupled, de-coupled, and recoupled with the external magnet over the external magnet use life.
- (3) The patient-contacting components of the device must be demonstrated to be biocompatible.
- (4) Performance data must demonstrate the sterility of the device components that are patientcontacting.
- (5) Methods and instructions for reprocessing reusable components must be validated.
- (6) Performance data must support shelf life by demonstrating continued sterility of the device or the sterile components and device functionality over the labeled shelf life.
- (7) Training must be developed and validated by human factors testing and analysis to ensure users can follow the instructions for use to allow safe use of the device.
- (8) Labeling must include:
- (a) Magnetic field safe zones.
- (b) Instructions for proper device use.
- (c) A screening checklist to ensure that all patients and operating staff are screened from bringing ferromagnetic implants, devices or objects near the external magnet.
- (d) Reprocessing instructions for any reusable components.
- (e) Shelf life.
- (f) Use life.
BENEFIT/RISK DETERMINATION
The risks of the Levita Magnetic Surgical System are based on nonclinical laboratory and animal studies as well as data collected in the clinical studies described above. One such risk could be diminished haptic feedback, which can result in applying to much force on the gallbladder wall resulting in tearing of the wall with bile and stone spillage. In the animal and clinical study, based on user feedback, there was some haptic feedback in dragging the external magnetic controller which also moves the internal detachable grasper when coupled.
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One minor risk is the abdominal wall injury, such as petechiae. Twenty (20) device-related events were noted in the clinical study. The device-related events were categorized as mild petechiae that were observed during the index procedure. The observed petechiae were mild and were not considered clinically significant by the study investigators, as all events resolved with no clinical sequelae. In addition, the mild petechiae reported represent much less trauma to the tissue than would be the case with a trocar insertion.
Another probable risk includes device usage in a contracted inflamed gallbladder may not provide ideal anatomic exposure and may require additional training to mitigate anatomic and pathologic variations in the gallbladder when using this device. Traditional laparoscopic graspers frequently require additional force and torque to achieve adequate exposure. The manipulation of this grasper in removing the gallbladder from the liver bed requires surgeon action and fundus response. However, this issue has been mitigated within the labeling by preventing the use of this device in difficult situations, such as "if adhesions, stones, or fibrosis interfere with exposure of the critical view of safety or definition of the components of the hepatocystic triangle". In addition, acute decoupling of the controller magnet and the grasper at critical points in surgery can be difficult to re-establish and the loss of exposure can result in injury. This is mitigated in the labeling by including language that explains that steps to re-establish coupling between the detachable grasper and the magnetic controller. Also, another risk involves injury resulting from recovery of loss of the detachable grasper in the abdominal cavity. However, this has been mitigated in the labeling by providing a safe and tested method of retrieving a lost detachable grasper and cautioning against doing it improperly.
The probable benefits of the device are also based on nonclinical laboratory and animal studies as well as data collected in the clinical studies as described above. The device allows for one less 5 mm port in the performance of laparoscopic cholecystectomy. This should result in several probable benefits. Since the studies presented were single armed, comparisons could not be made due to lack of a traditional laparoscopic cholecystectomy control. However, the subject device presents a novel method of providing surgical retraction that may provide a stepping stone to future minimally invasive surgical procedures. Such probable benefits include fewer episodes of inadvertent trocar injuries of intra-abdominal organs and structures within the abdominal wall (nerves and blood vessels), fewer episodes of instrument crowding, and one less abdominal wall scar resulting in better cosmesis.
The Levita Magnetic Surgical System, while providing tangible benefits, may be difficult to use by a surgeon who has not been familiarized with it prior to using it for the first time. A robust training program should overcome any learning curve that may exist.
Patient Perspectives
Although not a primary outcome of the clinical study conducted, a patient survey was completed as an additional assessment. The survey indicated that over 90% of the patients were satisfied on postoperative days 7 and 30.
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Benefit/Risk Conclusion
Given the information submitted in the de novo request, the data support that for the indication of "grasping and retracting the body and the fundus of the gallbladder in laparoscopic cholecystectomy procedures to facilitate access and visualization of the surgical site", the probable benefits outweigh the probable risks for the Levita Magnetic Surgical System. The device provides benefits and the risks can be mitigated by the use of general controls and the identified special controls.
CONCLUSION
The de novo request for the Levita Magnetic Surgical System is granted and the device is classified under the following:
Product Code: PNL Device Type: Magnetic Surgical Instrument System Class: II Regulation: 21 CFR 878.4815
§ 878.4815 Magnetic surgical instrument system.
(a)
Identification. A magnetic surgical instrument system is a prescription device used in laparoscopic surgical procedures consisting of several components, such as surgical instruments, and a magnetic controller. The magnetic controller is provided separately from the surgical instrument and is used outside the patient. The external magnetic controller is magnetically coupled with the internal surgical instrument(s) at the surgical site to grasp, hold, retract, mobilize, or manipulate soft tissue and organs.(b)
Classification. Class II (special controls). The special controls for this device are:(1) In vivo performance data must demonstrate that the device performs as intended under anticipated conditions of use. Testing must demonstrate the ability of the device to grasp, hold, retract, mobilize, or manipulate soft tissue and organs.
(2) Non-clinical performance data must demonstrate that the system performs as intended under anticipated conditions of use. The following performance characteristics must be tested:
(i) Magnetic field strength testing characterization to identify the distances from the magnet that are safe for patients and users with ferromagnetic implants, devices, or objects.
(ii) Ability of the internal surgical instrument(s) to be coupled, de-coupled, and re-coupled with the external magnet over the external magnet use life.
(3) The patient-contacting components of the device must be demonstrated to be biocompatible.
(4) Performance data must demonstrate the sterility of the device components that are patient-contacting.
(5) Methods and instructions for reprocessing reusable components must be validated.
(6) Performance data must support shelf life by demonstrating continued sterility of the device or the sterile components and device functionality over the labeled shelf life.
(7) Training must be developed and validated by human factors testing and analysis to ensure users can follow the instructions for use to allow safe use of the device.
(8) Labeling must include:
(i) Magnetic field safe zones.
(ii) Instructions for proper device use.
(iii) A screening checklist to ensure that all patients and operating staff are screened from bringing ferromagnetic implants, devices, or objects near the external magnet.
(iv) Reprocessing instructions for any reusable components.
(v) Shelf life.
(vi) Use life.