(257 days)
Not Found
No
The document describes a medical device (micro catheter) and its performance characteristics. There is no mention of AI, machine learning, or any form of computational intelligence in its description, intended use, or performance studies. The device's function is purely mechanical.
No.
The device is intended for the delivery of interventional devices or contrast media, which are not therapeutic actions in themselves, but rather facilitate other procedures.
No.
The device is intended for the delivery of interventional devices or contrast media, which are therapeutic or imaging purposes, not for diagnosing a medical condition itself.
No
The device is a physical medical device (a catheter) with specific dimensions, materials, and mechanical properties. The description details its physical characteristics, intended use for delivering devices/contrast, and studies verifying its mechanical performance and biocompatibility. There is no mention of software controlling its function or providing diagnostic interpretation.
No.
The device is a micro catheter used for delivering interventional devices or contrast media, which is an invasive therapeutic and diagnostic aid, not an in vitro diagnostic device for examining specimens derived from the human body.
No
This device is not indicated as a Predetermined Change Control Plan (PCCP) authorized device as there is no information mentioning a PCCP in the provided FDA clearance letter.
Intended Use / Indications for Use
The Micro Catheter is intended for the delivery of interventional devices or contrast media into the vasculature of the peripheral and neuro anatomy.
Product codes
KRA, QJP
Device Description
The Micro Catheter is a sterile, single-use, single lumen, variable stiffness, composite catheter. The Micro Catheter is available in three inner diameters (0.017″, 0.021″ and 0.027″), and two working lengths (150cm and 155cm). All models are designed with a straight tip, and are steam shapeable by the user. Single or dual radiopaque markers at the distal end facilitate fluoroscopic visualization. The outer surface of the catheter is coated with a hydrophilic coating to increase lubricity. The proximal end of Micro Catheter incorporates a standard luer adapter to facilitate the attachment of accessories. The catheter body has a semi-rigid proximal end which transitions into the flexible distal end to facilitate the advancement of the catheter in the tortuous vasculature. The Micro Catheter is compatible with ≤ 0.014″ guidewires and 5F or larger guide catheters.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Fluoroscopy (for visualization of radiopaque markers)
Anatomical Site
Peripheral and neuro anatomy vasculature
Indicated Patient Age Range
Not Found
Intended User / Care Setting
Not Found
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Study Type: Non-clinical bench testing and biocompatibility testing.
Sample Size: Not explicitly stated for each test, but implied by the successful completion of tests.
AUC: Not Applicable
MRMC: Not Applicable
Standalone Performance: Not Applicable
Key Results:
- Bench Performance Testing:
- Dimensional Verification: Met acceptance criteria.
- Radiopacity: Imaged showing equivalence to predicate.
- Surface Inspection: Met acceptance criteria.
- Corrosion Resistance: No signs of corrosion.
- Peak Tensile Force/Bond Strength: Met acceptance criteria.
- Liquid Leakage: No leakage.
- Air Leakage: No leakage.
- Hub Testing: Met acceptance criteria.
- Flowrate at Maximum Rated Infusion Pressure: Met acceptance criteria, comparable to predicate.
- Dynamic Burst Pressure: Met acceptance criteria.
- Static Burst Pressure: Met acceptance criteria.
- Simulated Use: Met acceptance criteria for preparation, ease of assembly, introducer sheath compatibility, ancillary device compatibility, trackability, lubricity, durability, and kink resistance.
- Flexibility and Kink Test: Met acceptance criteria.
- Torque Strength: Similar number of rotations to failure compared to cleared comparator.
- Coating Integrity: Met acceptance criteria.
- Coating Lubricity: Similar frictional forces compared to predicate.
- Particulate Evaluation: Similar particle numbers compared to predicate.
- Tip Stiffness: Similar tip stiffness compared to cleared comparator.
- Distal Tip Inspection: Met acceptance criteria.
- Tip Shapeability: Met acceptance criteria.
- Lumen Collapse: Similar forces to collapse compared to predicate.
- Compatibility tests: Met acceptance criteria.
- Biocompatibility Testing:
- ISO MEM Elution Test with L-929 Cells: Non-cytotoxic.
- ISO Guinea Pig Maximization Sensitization Test (2 Extracts): Non-sensitizer.
- Intracutaneous Reactivity Test in Rabbits (2 Extracts): Non-irritant.
- Acute Systemic Toxicity Study in Mice (2 Extracts): No evidence of acute systemic toxicity.
- Material-Mediated Pyrogenicity Test in Rabbits (Saline Extract): Non-pyrogenic.
- ASTM Hemolysis Test - Direct Contact and Extract Methods: Non-hemolytic.
- Complement Activation SC5b-9 Assay: Not an activator.
- Non-anticoagulated Venous Implant Study in Canines: Non-thrombogenic.
- Sterilization and Shelf Life:
- Sterilization: Verfied SAL of 10⁻⁶ using ethylene oxide according to ISO 11135.
- Shelf-life: Demonstrated 2-year shelf-life through aging studies. Packaging aging tests met acceptance criteria.
- Animal Study: Not deemed necessary.
- Clinical Study: Not deemed necessary.
Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)
Not Applicable (Performance metrics are related to mechanical characteristics and biocompatibility, not diagnostic accuracy).
Predicate Device(s)
Rebar™ Micro Catheter (K210114)
Reference Device(s)
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information
Not Found
§ 870.1210 Continuous flush catheter.
(a)
Identification. A continuous flush catheter is an attachment to a catheter-transducer system that permits continuous intravascular flushing at a slow infusion rate for the purpose of eliminating clotting, back-leakage, and waveform damping.(b)
Classification. Class II (performance standards).
U.S. Food & Drug Administration 510(k) Clearance Letter
Page 1
U.S. Food & Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993
www.fda.gov
Doc ID # 04017.08.00
July 30, 2025
Suzhou Zenith Vascular SciTech Limited
Jie Xia
Chief Executive Officer
Building 6, Block B, Phase 5, Biobay,
No.21 Dongyanli Road,
SIP Suzhou 215123
China
Re: K243534
Trade/Device Name: Micro Catheter
Regulation Number: 21 CFR 870.1210
Regulation Name: Continuous Flush Catheter
Regulatory Class: Class II
Product Code: KRA, QJP
Dated: June 26, 2025
Received: June 26, 2025
Dear Jie Xia:
We have reviewed your section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (the Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
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K243534 - Jie Xia
Page 2
Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).
Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reporting-combination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.
All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems.
For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-
Page 3
K243534 - Jie Xia
Page 3
assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Naira Muradyan -S
Naira Muradyan, Ph.D.
Assistant Director
DHT5A: Division of Neurosurgical,
Neurointerventional, and
Neurodiagnostic Devices
OHT5: Office of Neurological and
Physical Medicine Devices
Office of Product Evaluation and Quality
Center for Devices and Radiological Health
Enclosure
Page 4
FORM FDA 3881 (8/23)
Page 1 of 1
PSC Publishing Services (301) 443-6740 EF
DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration
Indications for Use
Form Approved: OMB No. 0910-0120
Expiration Date: 07/31/2026
See PRA Statement below.
510(k) Number (if known): K243534
Device Name: Micro Catheter
Indications for Use (Describe):
The Micro Catheter is intended for the delivery of interventional devices or contrast media into the vasculature of the peripheral and neuro anatomy.
Type of Use (Select one or both, as applicable)
☒ Prescription Use (Part 21 CFR 801 Subpart D)
☐ Over-The-Counter Use (21 CFR 801 Subpart C)
CONTINUE ON A SEPARATE PAGE IF NEEDED.
This section applies only to requirements of the Paperwork Reduction Act of 1995.
DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.
The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:
Department of Health and Human Services
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PRAStaff@fda.hhs.gov
"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."
Page 5
510(k) Summary-K243534
Micro Catheter K243534
1 / 5
Device Description
The Micro Catheter is a sterile, single-use, single lumen, variable stiffness, composite catheter. The Micro Catheter is available in three inner diameters (0.017″, 0.021″ and 0.027″), and two working lengths (150cm and 155cm). All models are designed with a straight tip, and are steam shapeable by the user. Single or dual radiopaque markers at the distal end facilitate fluoroscopic visualization. The outer surface of the catheter is coated with a hydrophilic coating to increase lubricity. The proximal end of Micro Catheter incorporates a standard luer adapter to facilitate the attachment of accessories. The catheter body has a semi-rigid proximal end which transitions into the flexible distal end to facilitate the advancement of the catheter in the tortuous vasculature. The Micro Catheter is compatible with ≤ 0.014″ guidewires and 5F or larger guide catheters.
| Applicant | Suzhou Zenith Vascular SciTech Limited |
|---|---|
| Building 6, Block B, Phase 5, Biobay, No.21 Dongyanli Road, SIP Suzhou, China 215123 | |
| Contact Person | Jie Xia |
| Contact Telephone | +86-18051093308 |
| Date Prepared | July 28, 2025 |
| Device Trade Name | Micro Catheter |
| Common Name | Percutaneous Catheter |
| Regulation Number | 21 CFR 870.1210, 21 CFR 870.1250 |
| Regulation Name | Continuous Flush Catheter, Percutaneous Catheter, Neurovasculature |
| Product Code | KRA, QJP |
| Device Classification | Class II |
| Predicate Device | Rebar™ Micro Catheter (K210114) |
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Micro Catheter K243534
2 / 5
Indications for Use
The Micro Catheter is intended for the delivery of interventional devices or contrast media into the vasculature of the peripheral and neuro anatomy.
Predicate Device Comparison
The predicate device for the Micro Catheter is the Rebar™ Micro Catheter (K210114). The table below describes the differences between the subject and predicate device.
Table 1. Comparison of the Subject Device and Predicate Device
| Characteristics | Subject Device- Micro Catheter(K243534) | Predicate Device- Rebar Micro Catheter(K210114) | Justification of Substantial Equivalence |
|---|---|---|---|
| Product Code | KRA, QJP | KRA, QJP | Same |
| Indications for Use | The Micro Catheter is intended for the delivery of interventional devices or contrast media into the vasculature of the peripheral and neuro anatomy. | The Rebar™ Micro Catheter is intended for the delivery of interventional devices or contrast media into the vasculature of the peripheral and neuro anatomy. | Same |
| Materials | |||
| Inner Layer | PTFE | PTFE | Same |
| Middle Layer | Stainless steel | Stainless steel | Same |
| Outer Jacket | Pebax | Pebax | Same |
| Coating | Hydrophilic coating | Hydrophilic coating | Same |
| Radiopaque Marker | Platinum-Iridium Alloy | Platinum-Iridium Alloy | Same |
| Strain Relief | Polyurethane/PU | Elvax and Dynaflex | Different. The subject device was evaluated via bench and biocompatibility testing with passing or acceptable results. |
| Hub | Polycarbonate | Polypropylene | |
| Specification | |||
| Model | 200017150/200017155, 200021150/200021155, 200027150/200027155 | Rebar 18, Rebar 27 | N/A |
| Proximal OD | 0.81 mm, 0.91 mm, 0.93 mm | 0.89 mm Max, 1.09 mm Max | Similar. The design validation testing has demonstrated the subject device performs as intended. |
| Distal OD | 0.66 mm, 0.81 mm, 0.93 mm | 0.93 mm Max, 1.09 mm Max | |
| Inner Diameter | 0.017 inch, 0.021 inch, 0.027 inch | 0.020 inch Min, 0.026 inch Min | |
| Effective Length | 150 cm and 155 cm | 130 cm and 153 cm, 130 cm and 145cm | |
| Coating Length | 80 cm, 100 cm, 95 cm | ||
| Tip Configuration | Straight, shapeable | Straight, shapeable | Same |
| Sterilization Method | Ethylene Oxide | Ethylene Oxide | Same |
| How Supplied | Sterile, non-pyrogenic. | Sterile, non-pyrogenic. | Same |
| Shelf-Life | 2 years | 2 years | Same |
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Micro Catheter K243534
3 / 5
Performance Data
The Micro Catheter was evaluated via the following non-clinical testing.
Performance Testing-Bench
The following bench performance testing was performed to characterize the Micro Catheter.
Table 2. Bench Performance Testing
| Test | Test Method Summary | Results |
|---|---|---|
| Dimensional Verification | The dimensions (Inner Diameter, Outer Diameter, Effective Length) of the catheter were measured. The inner diameter of the introducer sheath was measured. The outer diameter of the shaping mandrel was measured. | Micro Catheter and accessories met the acceptance criteria. |
| Radiopacity | The catheter was visualized under fluoroscopy. | Micro Catheter and the predicate device were imaged showing equivalence in terms of radiopacity. |
| Surface Inspection | The catheter was visually inspected under microscopy. | Micro Catheter met the acceptance criteria. |
| Corrosion Resistance | The catheter was tested according to ISO 10555-1, Annex A. | Micro Catheter showed no signs of corrosion. |
| Peak Tensile Force/Bond Strength | The catheter was evaluated to verify the peak tensile force/bond strength of the full system meets the minimum tensile strength requirement. | Micro Catheter met the acceptance criteria. |
| Liquid Leakage | The catheter was tested according to ISO 10555-1, Annex C. | Micro Catheter showed no leakage. |
| Air Leakage | The catheter was tested according to ISO 10555-1, Annex I. | Micro Catheter showed no leakage. |
| Hub Testing | The hub was tested according to ISO 80369-20. | Micro Catheter hub met the acceptance criteria. |
| Flowrate at Maximum Rated Infusion Pressure | The flow rate at the maximum rated infusion pressure was measured using saline, 50:50 saline: contrast, and 100% contrast. | Micro Catheter met the acceptance criteria. The mean flow rate values for the subject device and predicate device are comparable for the injectate media tested. |
| Dynamic Burst Pressure | The catheter was tested according to ISO 10555-1, Annex G. | Micro Catheter met the acceptance criteria. |
| Static Burst Pressure | The catheter was tested according to ISO 10555-1, Annex F. | Micro Catheter met the acceptance criteria. |
| Simulated Use | The catheter was evaluated in a simulated anatomical model for the preparation and ease of assembly, introducer sheath compatibility and peel away, ancillary device compatibility with a guidewire and guide catheter, trackability, lubricity and durability of the hydrophilic coating, and kink resistance. | Micro Catheter met the acceptance criteria. |
| Flexibility and Kink Test | The catheter was evaluated for resistance to kinking around bends with clinically relevant radii. | Micro Catheter met the acceptance criteria. |
| Torque Strength | The catheter was evaluated for torque strength by rotating the test samples in an anatomical model with the distal tip fixed | Micro Catheter and a cleared comparator showed a similar number of rotations to |
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Micro Catheter K243534
4 / 5
| Test | Test Method Summary | Results |
|---|---|---|
| and recording the number of rotations to failure. | failure. | |
| Coating Integrity | The catheter coating integrity was inspected pre- and post-simulated use in an anatomical model. | Micro Catheter met the acceptance criteria. |
| Coating Lubricity | The catheter was evaluated for frictional forces on a universal testing machine. | Micro Catheter and the predicate showed similar frictional forces. |
| Particulate Evaluation | The catheter was evaluated for particulate generation during simulated use in an anatomical model. | Micro Catheter and the predicate showed similar particle numbers. |
| Tip Stiffness | The distal tip of the catheter was deflected on a universal testing machine. | Micro Catheter and a cleared comparator showed a similar tip stiffness. |
| Distal Tip Inspection | The distal tip of the catheter was inspected for defects. | Distal tip met the acceptance criteria. |
| Tip Shapeability | The distal tip of the catheter was shaped using the shaping mandrel supplied with Micro Catheter. | Distal tip met the acceptance criteria. |
| Lumen Collapse | The force needed to collapse the catheter at the tip and along the catheter shaft was measured using a universal testing machine. | Micro Catheter and the predicate showed similar forces to collapse the catheter. |
| Compatibility tests | The catheter was inspected for damage post simulated use testing with compatible interventional devices in a neurovascular model. | Micro Catheter met the acceptance criteria. |
The performance data demonstrate that the subject device is substantially equivalent to the predicate devices.
Biocompatibility Testing
Biocompatibility tests were conducted with the Micro Catheter in accordance with ISO 10993-1:2018, "Biological evaluation of medical devices - Part 1: Evaluation and testing within a risk management process", and the FDA biological evaluation guidance. The performed tests are listed in Table 3.
Table 3. Biocompatibility Testing
| Test | Standards | Results | Conclusion |
|---|---|---|---|
| ISO MEM Elution Test with L-929 Cells | ISO 10993-5 | The test article had a reactivity grade of ≤2 under the conditions of this study. | Non-cytotoxic |
| ISO Guinea Pig Maximization Sensitization Test (2 Extracts) | ISO 10993-10 | The saline and sesame oil test article extracts did not show evidence of causing delayed dermal contact sensitization response in the guinea pigs. | Non-sensitizer |
| Intracutaneous Reactivity Test in Rabbits (2 Extracts) | ISO 10993-23 | The differences between the test extracts and their respective control mean scores were less than 1.0. | Non-irritant |
| Acute Systemic Toxicity Study in Mice (2 Extracts) | ISO 10993-11 | There was no mortality or evidence of acute systemic toxicity from the extracts. | No evidence of acute systemic toxicity |
| Material-Mediated Pyrogenicity Test in Rabbits (Saline Extract) | ISO 10993-11 | None of the test rabbits exhibited a temperature rise greater than or equal to 0.5°C. | Non-pyrogenic |
| ASTM Hemolysis Test - Direct Contact and Extract Methods | ISO 10993-4 | The test article hemolytic index was above the negative control and was less than 2% for both direct contact and extract methods under the conditions of this study. | Non-hemolytic |
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Micro Catheter K243534
5 / 5
| Test | Standards | Results | Conclusion |
|---|---|---|---|
| Complement Activation SC5b-9 Assay (with Comparator Control Article) | ISO 10993-4 | The concentration of SC5b-9 activated by the test article was statistically lower than that activated by the negative reference material and comparator control article. | Not an activator |
| Non-anticoagulated Venous Implant Study in Canines for Evaluation of Thromboresistance | ISO 10993-4 | The extent of thrombus formation on the test article was not greater than the comparator control article. | Non-thrombogenic |
Sterilization and Shelf Life
The Micro Catheter is sterilized using ethylene oxide. The sterilization cycle was verified to ensure a sterility assurance level (SAL) of 10⁻⁶ in accordance with ISO 11135.
Aging studies for subject device have been conducted and demonstrated a 2 year shelf-life. Packaging aging tests were also conducted and the results met all acceptance criteria.
Packaging
Each package consists of a Sterile Barrier System (SBS) and protective packaging. SBS validation was conducted per requirements of ISO 11607-2.
Animal Study
An animal study was not deemed necessary to support the substantial equivalence of the subject device to the predicate device. Non-clinical testing described above was determined to be sufficient to support substantial equivalence.
Clinical Study
Clinical testing was not deemed necessary to support the substantial equivalence of the subject device to the predicate device. Non-clinical testing described above was determined to be sufficient to support substantial equivalence.
Conclusion
The subject and predicate devices have the same intended use and the same or similar technological characteristics. The non-clinical testing demonstrates that the subject Micro Catheter performs as intended and supports substantial equivalence to the predicate device. The differences in technological characteristics do not raise new questions of safety and effectiveness.