(58 days)
The ClearPoint System is intended to provide stereotactic guidance for the placement and operation of instruments or devices during planning and operation of neurological procedures within an operating room environment and in conjunction with MR and/or CT imaging. During planning, the system is intended to provide functionality for the automatic identification, labeling, visualization of segmentable brain structures from a set of loaded MR images. The ClearPoint System is intended as an integral part of procedures that have traditionally used stereotactic methodology. These procedures include biopsies, catheter and electrode insertion including deep brain stimulation (DBS) (asleep or awake) lead placement. When used in an MRI environment, the system is intended for use only with 1.5 and 3.0 Tesla MRI scanners and MR Conditional implants and devices.
The updated ClearPoint Software Version 3.0 introduces modifications to support a new clinical workflow using intraoperative CT imaging when compared to the previous ClearPoint Software Version 2.2 (K233243). The ClearPoint System described in this submission is essentially identical from a technological standpoint to the cleared predicate device described in K233243 (ClearPoint System version 2.2). As mentioned above, since the prior clearance, the company has implemented software features to enable usage of the ClearPoint System during CT-guided procedures, in addition to MR-guided procedures supported in the predicate device. The hardware components are unchanged from the device described in K233243 and minor changes were made to the indications for use.
The ClearPoint System is comprised of a workstation laptop with software, the SMARTGrid Planning Grid, the SMARTFrame Trajectory Frame, the SMARTFrame Accessory Kit and the SMARTFrame Thumbwheel Extension. The SMARTGrid and associated Marking Tool are designed to assist the physician to precisely position the entry hole as called out in the trajectory planning software. The SMARTFrame is an Adjustable Trajectory Frame (ATF) that provides the guidance and fixation for neurosurgical tools. The image-visible fluids of the Targeting Cannula along with the fiducial markers in the base of the frame allows for trajectory feedback when the physician views the intraoperatively acquired images, makes changes and confirms with subsequent image acquisitions. Optionally, the ClearPoint System can be used with any head fixation frame to immobilize the patient's head with respect to the scanner table. ClearPoint Neuro also supplies an optional head fixation frame that can be used with the ClearPoint System. The ClearPoint Workstation includes the ClearPoint Workstation Software (for trajectory planning and monitoring) and a Laptop Computer. The hardware components of the current ClearPoint System are the SMARTFrame and Accessories. They are all single use devices that are provided sterile and include the SMARTGrid Planning Grid (Marking Grid, Marking Tool), SMARTFrame Pack (SMARTFrame or SMARTFrame XG, Centering Device and Wharen Centering Guide, Dock, Device Lock, Screwdriver, Roll Lock Screw and Washer), Rescue Screws (Extra Titanium Screws), Thumbwheel Extension, Accessory Kit (Peel-away Sheath, Stylet, Lancet, Depth Stop, Ruler), Scalp Mount Base, and Guide Tubes and Device Guide Packs (Guide Cannulas). In addition, the ClearPoint System is used with the separately cleared or Class I, 510(k) exempt products: SmartTip MRI Hand Drill and Drill Bit Kit, MRI Neuro Procedure Drape, with Marker Pen and Cover, and SmartFrame Fiducial.
The provided document (K243657) is a 510(k) Premarket Notification for the ClearPoint System (Software Version 3.0), which is a stereotaxic instrument. The document primarily focuses on demonstrating substantial equivalence to predicate devices and detailing the non-clinical testing performed.
Based on the provided text, here's a description of the acceptance criteria and the study that proves the device meets the acceptance criteria, addressing each point as much as possible:
1. A table of acceptance criteria and the reported device performance
The document provides accuracy specifications in tables:
Table 1: ClearPoint System Accuracy Specifications - MRI Guidance (Unchanged from predicate)
| Performance Validation | Positional Error (mm) | Angular Error (deg.) | ||||
|---|---|---|---|---|---|---|
| ClearPoint System | Mean (X,Y,Z) | Std. Dev. | 99% CI | Mean | Std. Dev. | 99% CI |
| 0.14 | 0.37 | 0.44 | 0.32° | 0.17° | 0.46° | |
| 0.16 | 0.54 | 0.60 | ||||
| 0.56 | 0.57 | 0.10 |
Note: The table layout in the original document for MRI accuracy is a bit unusual with duplicated rows for positional error, and it's not explicitly labelled as "acceptance criteria." However, it presents the validated performance.
Table 2: ClearPoint System Accuracy Specifications - CT Guidance (New for v3.0)
| Precision ME (mm) | Accuracy RMS (mm) | Accuracy Max (mm) | |
|---|---|---|---|
| X | 0.1 | 0.17 | 0.3 |
| Y | 0.1 | 0.17 | 0.3 |
| Z | 0.1 | 0.17 | 0.3 |
| Roll | 0.1° | 0.17° | 0.3° |
| Pitch | 0.1° | 0.17° | 0.3° |
| Yaw | 0.1° | 0.17° | 0.3° |
| Positional Error (mm) | Trajectory Angle Error (Degrees) | ||||
|---|---|---|---|---|---|
| Mean | Standard Deviation | 99% CI Upper Bound | Mean | Standard Deviation | 99% CI Upper Bound |
| 0.81 | 0.49 | 0.93 | 0.31 | 0.23 | 0.37 |
Explicit Acceptance Criteria (from "Targeting Accuracy" row in Table 3 comparison):
- Targeting Accuracy: ± 1.5 mm @ ≤125mm (This appears to be the primary specified acceptance criterion for overall targeting accuracy, presumably applying across both MRI and CT guidance given its placement in the general comparison table).
Reported Device Performance:
- MRI Guidance: Positional Error (99% CI) 0.44 mm, 0.60 mm, 0.10 mm. Angular Error (99% CI) 0.46°. These values are well within the ± 1.5 mm overall targeting accuracy.
- CT Guidance: Positional Error (99% CI Upper Bound) 0.93 mm. Trajectory Angle Error (99% CI Upper Bound) 0.37°. These values are also well within the ± 1.5 mm overall targeting accuracy.
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document states:
- "Accuracy testing was performed using an MRI scanner to confirm that modifications included in the ClearPoint System 3.0 did not cause any unexpected changes in the accuracy specifications of the software, with successful results."
- "Additionally, accuracy testing was performed in a CT scanner to validate the CT-guided clinical workflow that is new to the ClearPoint 3.0 software and establish new ground-truth accuracy specifications."
However, the document does not specify the sample size for either the MRI or CT accuracy test sets.
The data provenance is also not specified regarding country of origin or whether it was retrospective or prospective. Given the nature of accuracy testing for a stereotaxic device, these are typically phantom-based, prospective tests conducted in a controlled lab or clinical environment, rather than patient data studies.
3. 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)
The document does not mention human experts for establishing ground truth for the accuracy tests. The accuracy testing described appears to be technical validation against a known physical ground truth (e.g., phantom measurements), as is common for stereotaxic instrument validation. Therefore, expert consensus on images is not relevant for this type of accuracy assessment.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable, as the accuracy testing described is a technical validation against a physical ground truth, not a study evaluating human interpretation or a scenario requiring adjudication.
5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
The document does not mention any MRMC comparative effectiveness study or any evaluation of human readers (even though the device has "automatic identification, labeling, visualization" of structures). The testing detailed is primarily focused on the system's technical accuracy in guidance, not on AI assistance for human image interpretation.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, the accuracy testing described in Section 6, "Non-Clinical Testing," and detailed in Tables 1 and 2, represents standalone (algorithm only) performance testing against a technical ground truth. It evaluates the system's precision and accuracy in positional and angular measurements.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The ground truth used for the accuracy tests appears to be physical measurements from a phantom or test setup, given the context of "Positional Error" and "Angular Error" in millimeters and degrees. The document refers to "establish new ground-truth accuracy specifications" in relation to the CT testing, implying a precise, measurable standard. This is typical for the technical validation of stereotaxic guidance systems.
8. The sample size for the training set
The document does not specify a sample size for a "training set." The ClearPoint System 3.0 software introduces features like "automatic identification, labeling, visualization, and quantification of segmentable brain structures" and "Algorithms to automatically locate and identify marking grid, targeting frame components, cannula, and device tip from both MR and CT image sets." While these imply the use of machine learning or advanced algorithms that would require training data, the submission focuses on the validation of these features' accuracy, not on the details of their development (including training data specifics).
9. How the ground truth for the training set was established
Since the document does not discuss a training set, there is no information provided on how its ground truth was established. For the algorithms processing anatomical structures or hardware components, the ground truth for training data would typically involve manually annotated medical images by qualified personnel (e.g., radiologists, neurosurgeons, or trained annotators under expert supervision).
§ 882.4560 Stereotaxic instrument.
(a)
Identification. A stereotaxic instrument is a device consisting of a rigid frame with a calibrated guide mechanism for precisely positioning probes or other devices within a patient's brain, spinal cord, or other part of the nervous system.(b)
Classification. Class II (performance standards).