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Phasor EZ-Fiducials is intended to provide fixed reference point(s) in patients requiring stereotactic surgery in conjunction with CT imaging with the included screws placed using the included EZ-Driver (electric screwdriver) or manual screwdriver exclusively for each.

Phasor EZ-FIDUCIALS™ provide fixed reference points during neurosurgical procedures. The device is composed of 3 items, all single-use, provided gamma-sterilized, and placed within the same primary packaging (sealed Tyvek tray within a shelf carton):

1. Screws: Each of the four provided titanium screws is identical, with specific dimensions of each EZ-Fiducials screw as follows: screwhead circular shape screwhead with square-shaped engagement, non-threaded shaft diameter 2.9mm and length 15mm, threaded shaft diameter (major threads) 1.98mm, thread length 5mm; no protective caps are provided, and the screws should exclusively be utilized in conjunction with the screwdrivers (manual or EZ-Driver) provided together in the same tray (and with no other screwdriver);

2. Manual Screwdriver: handheld, to be solely used with the screws provided, not intended for use with any other screws;

3. EZ-driver: (electric, handheld, non-rechargeable battery-operated screwdriver, without software, single-use for solely tightening or loosening the provided screws exclusively, not intended for use with any other screws).

The provided FDA 510(k) clearance letter and summary for EZ-Fiducials focuses primarily on substantial equivalence to predicate devices based on technological characteristics and bench testing, rather than a clinical study with acceptance criteria based on human-in-the-loop performance or algorithm-only performance against a defined ground truth.

Therefore, for aspects related to "device performance," "acceptance criteria," "sample size," "expert ground truth," "adjudication methods," "MRMC studies," "standalone performance," and "ground truth for training/test sets," the available document does not provide this information. The submission relies on bench testing to demonstrate equivalence.

Here's an analysis of what information is provided and what explicitly is not provided based on your request:

Acceptance Criteria and Device Performance (Based on Available Information)

The document does not present a table of acceptance criteria and reported device performance in the manner typically seen for clinical or AI/algorithm performance studies (e.g., sensitivity, specificity, accuracy). Instead, it relies on demonstrating compliance with an ASTM standard and general performance adequacy, often by comparison to predicate devices' known characteristics.

Table of Acceptance Criteria and Reported Device Performance (as inferred from the document):

Study Proving Device Meets Acceptance Criteria

The study proving the device meets acceptance criteria is primarily bench testing. No clinical study data is presented.

1. A table of acceptance criteria and the reported device performance:

• See table above. This is inferred from the discussion of performance testing. Explicit quantitative acceptance criteria (e.g., "deflection must be less than X mm") are not detailed, but compliance with ASTM F543-23 and "adequate performance" are stated.

2. Sample size used for the test set and the data provenance:

• Sample Size: Not explicitly stated for bench testing. The testing refers to "bone simulant" but the quantity of fiducials, screws, or instances tested is not specified.
• Data Provenance: Not applicable in terms of patient data. The testing is bench testing using "bone simulant." There is no indication of retrospective or prospective data or country of origin, as it's not a clinical study.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

• Not applicable. This was a bench study, not a study requiring expert ground truth for clinical cases. The "ground truth" for the bench testing would be physical measurements and compliance with engineering standards.

4. Adjudication method (e.g., 2+1, 3+1, none) for the test set:

• Not applicable. There was no human interpretation or subjective assessment of clinical data that would require adjudication.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:

• No. An MRMC study was not done. The device is a physical fiducial system and an electric screwdriver, not an AI or software device that assists human readers.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:

• Not applicable. This is not an AI algorithm. The device performance here refers to the physical characteristics and functionality of the fiducials and screwdriver.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc):

• Bench Testing Data/Engineering Standards. The ground truth for this submission's performance assessment is the physical performance and measurements of the device (deflection) and compliance with industry standards (ASTM F543-23).

8. The sample size for the training set:

• Not applicable. This device does not use machine learning or AI, so there is no training set.

9. How the ground truth for the training set was established:

• Not applicable. As above, no training set.

Summary of the Study:

The "study" referenced in the 510(k) for EZ-Fiducials is a series of bench tests focusing on:

• Biocompatibility of materials.
• Sterility validation.
• Packaging integrity.
• Performance of the screws (e.g., deflection characteristics, compliance with ASTM F543-23 when inserted into bone simulant).
• Performance of the electric screwdriver (its ability to drive screws adequately).

The clearance is based on the argument that these bench tests demonstrate the device's substantial equivalence in terms of safety and effectiveness to the predicate device (Medtronic Navigus Unibody Fiducial Marker System) and a reference device (OsteoMed Pinnacle Driver), even with some technological differences (e.g., screwdriver speed, sterilization method). The document explicitly states: "No clinical testing was needed or performed otherwise." The predicate device was also "cleared based upon bench testing alone."

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Phasor EVAC™ is indicated when access to and evacuation of a cranial subacute or chronic hematoma or hygroma is necessary. The EVAC system is intended for drainage of subdural fluid accumulations such as hygromas and chronic or subacute hematomas to an external suction reservoir. The EVAC system is also intended for draining air and fluids from the subdural space immediately following craniotomy procedures performed to remove a chronic or subacute subdural hematoma.

Phasor EVAC™ subdural evacuation system is indicated when access to the subdural space and evacuation of a cranial subacute or chronic hematoma or hygroma is necessary. The EVAC system consists of surgical instruments and accessories used for draining subdural fluid accumulations such as hygromas and chronic or subacute hematomas to an external suction reservoir without touching the brain. Utilizing a minimally invasive technique, the EVAC system components are designed to promote gradual brain re-expansion by creating a low homogeneous negative pressure throughout the subdural space as fluid is drained to an external suction reservoir.

This 510(k) clearance letter for the EVAC device (K243205) indicates that it is a central nervous system fluid shunt and components and it's regulated under 21 CFR 882.5550. While the letter confirms the device's substantial equivalence to predicate devices and states that various tests were conducted, it does not provide detailed information about specific acceptance criteria, study methodologies (like sample size, ground truth establishment, expert qualifications, or MRMC studies), or actual performance data in the format requested.

The document primarily focuses on explaining why the device is considered substantially equivalent to existing devices based on its intended use, indications for use, and technological characteristics. It mentions that "Various tests including for biocompatibility, packaging, sterility, safety, and performance were conducted and passed successfully," and that "testing for a closed system with firm purchase into bone was established and verified by testing." However, it does not disclose the specific data or criteria for these tests. It explicitly states, "No clinical testing was needed or performed otherwise."

Therefore, based on the provided FDA 510(k) clearance letter, I cannot populate the detailed table and answer all the specific questions about acceptance criteria and study proving device performance as requested, because this information is typically contained in the actual 510(k) submission, not the clearance letter itself. The clearance letter summarizes the FDA's decision, but not the detailed technical data from the submission.

Here's what can be inferred or explicitly stated from the provided document, with notes where information is not present:

Acceptance Criteria and Device Performance (Based on Inferred Safety and Effectiveness)

The acceptance criteria for a 510(k) cleared device are implicitly that it demonstrates substantial equivalence to a predicate device, meaning it is as safe and effective while having the same intended use. For this device, the "performance" described is its ability to meet the design intent and demonstrate equivalence through bench testing, rather than clinical efficacy.

Table 1: Inferred Acceptance Criteria and Reported Device Performance

Study Details (Based on Available Information)

1. Sample size used for the test set and the data provenance:

   • The document states "No clinical testing was needed or performed otherwise." This indicates that the "test set" for demonstrating substantial equivalence was primarily based on bench testing and engineering evaluations of the device components and system.
   • Specific sample sizes for these bench tests are not provided in the clearance letter.
   • Data provenance (country of origin, retrospective/prospective): Not applicable or specified for bench testing.

2. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience):

   • Given that "No clinical testing was needed or performed," there's no mention of expert panels establishing ground truth in a clinical context. The "ground truth" for the engineering tests would be derived from accepted engineering standards and specifications.

3. Adjudication method (e.g. 2+1, 3+1, none) for the test set:

   • Not applicable, as no clinical study or human reader evaluation requiring adjudication was performed.

4. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:

   • No, an MRMC comparative effectiveness study was not done. The device is a surgical system (shunt and components), not an AI-assisted diagnostic tool.

5. If a standalone (i.e. algorithm only without human-in-the loop performance) was done:

   • This question is more pertinent to software/AI devices. The EVAC system is a mechanical device. Its "performance" refers to its physical functioning (e.g., maintaining a closed system, firm purchase into bone), not an algorithmic output. The "Phasor Drill" component is explicitly stated to have been previously cleared (K161704), indicating its standalone performance was established previously.

6. The type of ground truth used (expert consensus, pathology, outcomes data, etc):

   • For this device, the "ground truth" for its functional performance was based on engineering specifications, material science standards, and mechanical testing requirements (e.g., ability to form a "closed system with firm purchase into bone"). There's no mention of clinical ground truth (like pathology or outcomes data) because no clinical study was performed.

7. The sample size for the training set:

   • Not applicable. This is a hardware device, not an AI/machine learning algorithm requiring a "training set."

8. How the ground truth for the training set was established:

   • Not applicable for the same reason as above.

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