The Leksell® Image Guidance Surgical System (LIGS) is intended for use in cranial and spinal neurosurgical procedures to provide image guidance based on preoperative images which are visualized interactively with the aid of surgical tools.

Device Description

The Leksell® Image Guidance Surgical System (hereafter the LIGS System) which is the subject of this 510(k) Premarket Notification is a device System intended for use in neurosurgical procedures to provide image guidance based upon preoperative images which are visualized interactively with the aid of surgical tools. The LIGS System imports Computer Tomography (CT) and Magnetic Resonance (MR) images and provides a visual display of the images for pre-planning surgical paths. The images and pre-planned surgical paths can be viewed at a computer workstation in the operating room. The LIGS System is integrated with a Measurement System, which allows the patient in the operating room environment to be correlated with the diagnostic images obtained pre-operatively. The LIGS System may then be used for visual or instrumentation guidance during the surgical procedure.

The LIGS System is a modular System comprised of a set of components which may be used in conjunction with three basic Models of system configuration interfaced with a Measurement (position tracking) System:

The SurgiScope® Model is configured around a motorized ceiling mounted Integrated Tool Support System with integrated tool support software.
The ViewScope® Model is configured for use with a manual Floorstand Microscope System.
The FreeHand Model allows for the tracking of surgical tools without the use of a microscope.

The LIGS System consists of 6 major components that may be combined in different permutations in the SurgiScope®, ViewScope®, and proposed FreeHand Models. The six primary components of the LIGS System may be combined in various configurations, depending upon the features desired by the customer.

AI/ML Overview

The provided document is a 510(k) Premarket Notification for the Leksell® Image Guidance Surgical System (LIGS). It describes the device, its intended use, and states that validation and verification studies were conducted. However, the document does NOT contain the detailed information necessary to fully answer all components of your request, specifically:

Quantitative Acceptance Criteria: The document states that the system is "capable of safely and accurately performing the stated intended use" but does not define specific, quantifiable acceptance criteria (e.g., accuracy, precision metrics with numerical thresholds).
Reported Device Performance: While it mentions studies were conducted, it does not provide the results of those studies in a quantifiable manner against any specific performance metrics.
Sample Size and Provenance of the Test Set: No information is given about the number of patients or cases used for testing, nor where the data originated (country, retrospective/prospective).
Number and Qualifications of Experts for Ground Truth: There is no mention of experts, their number, or their qualifications for establishing ground truth in any test set.
Adjudication Method: No information is provided regarding adjudication methods (e.g., 2+1).
Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study: There is no indication that such a study was performed, nor any data on effect size for human readers with and without AI assistance.
Standalone Performance: While the system is described, the document doesn't explicitly state "standalone performance" in the context of an algorithm without human-in-the-loop, likely because this system is inherently designed for human interaction.
Type of Ground Truth: The document doesn't specify if ground truth was established by expert consensus, pathology, or outcomes data.
Sample Size for Training Set: There is no information about a training set or its size.
How Ground Truth for Training Set was Established: Since no training set is mentioned, there's no information on how its ground truth was established.

Based on the provided text, here is what can be extracted and what is missing:

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

Acceptance Criteria (Stated broadly)	Reported Device Performance (Stated broadly)
Capable of safely performing the stated intended use.	The results of performance testing demonstrate that the Leksell® Image Guidance Surgical System is capable of safely...
Capable of accurately performing the stated intended use (neuro-surgical procedures to provide image guidance).	...and accurately performing the stated intended use (neuro-surgical procedures to provide image guidance).
Be substantially equivalent to predicate devices.	The FDA has determined the device is substantially equivalent to predicate devices for the indications for use stated.
Technological characteristics similar to predicate devices, without affecting relative safety or effectiveness.	Fundamental technical characteristics are similar to predicate devices. Differences relate to physical appearance and materials that do not affect relative safety or effectiveness.

Missing: Specific, quantifiable numerical acceptance criteria (e.g., accuracy +/- X mm, precision Y%) and the corresponding measured device performance values.

2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

Sample Size: Not specified.
Data Provenance: Not specified (e.g., country of origin, retrospective/prospective nature of data).

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)

Number of Experts: Not specified.
Qualifications of Experts: Not specified.

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

Adjudication Method: Not specified.

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

MRMC Study: Not mentioned as being conducted.
Effect Size: Not applicable, as no MRMC study is mentioned.

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

The LIGS system is described as an interactive image guidance system for use with surgical tools and a surgeon. The concept of "standalone (algorithm only without human-in-the-loop performance)" does not apply directly to this type of device, as its core function is to provide guidance to a human during surgery. Therefore, a standalone performance study in the way it's typically understood for diagnostic AI wouldn't be relevant or detailed here.

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

Type of Ground Truth: Not specified.

8. The sample size for the training set

Sample Size: Not specified. This document is focused on regulatory submission and does not detail development or training data.

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

Ground Truth Establishment: Not specified.

Summary of the Study that Proves the Device Meets Acceptance Criteria:

The document states: "Validation and verification studies were conducted to evaluate the performance characteristics of the Leksell® Image Guidance Surgical System. The results of these studies demonstrated that the Leksell® Image Guidance Surgical System is capable of safely and accurately performing the stated intended use."

The FDA's clearance letter confirms: "We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent... You may, therefore, market the device..."

Missing: The specific details, methodology, results, and statistical analysis of these "validation and verification studies" are not provided in the publicly available 510(k) summary. These studies would contain the quantitative data to support the claims of safety and accuracy.

Summary

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Original 510(k) Premarket Notification Leksell® Image Guidance Surgical System

K973684

MAR 31 1998

510(K) SUMMARY SECTION 21

This 510(k) Summary is being submitted in accordance with the requirements of SMDA 1990 and CFR 807.92.

SUBMITTER INFORMATION SECTION 21.1

a.	Company Name:	Elekta Instruments AB
b.	Company Address:	Birger Jarlsgatan 53Stockholm, Sweden S-103 93
c.	Company Phone:Company Facsimile:	(011) 46 8402 5400(011) 46 8402 5500
d.	Contact Person:	Sverker GlansVice PresidentQuality and Regulatory AffairsElekta Instruments AB

DEVICE IDENTIFICATION SECTION 21.2

a.	Trade/Proprietary Name:	Leksell® Image Guidance Surgical System(LIGS)
b.	Common Name	Neurological Image Guided Surgical System
c.	Classification Name:	Stereotaxic InstrumentComputed Tomography System
d.	Device Class:	Class II (per 21 CFR 882.4560, 21CFR892.1750)

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IDENTIFICATION OF PREDICATE DEVICES SECTION 21.3

Table 21.1 provides relevant information on the predicate devices for the LIGS System.

DEVICE NAME	COMPANY	510(K)NUMBER	510(K)CLEARANCE DATE
Elekta Leksell®Image GuidanceSystem (LIGS)	Elekta InstrumentsAB	K961639	26-July-96
ISG Family ofViewing Wands®(cranial applications)	I.S.G.Technologies, Inc.	K960714	29-May-96
ISG Family ofViewing Wands®(spinal applications)	I.S.G.Technologies, Inc.	K970865	4-June-97

SECTION 21.4 DEVICE DESCRIPTION

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obtained pre-operatively. The LIGS System may then be used for visual or instrumentation guidance during the surgical procedure.

1. The SurgiScope® Model is configured around a motorized ceiling mounted Integrated Tool Support System with integrated tool support software.
1. The ViewScope® Model is configured for use with a manual Floorstand Microscope System.
1. The FreeHand Model allows for the tracking of surgical tools without the use of a microscope.

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Table 21.2

Component of LIGS	LIGS Model
	ViewScope®	SurgiScope®	FreeHand
ScopePlan® Imaging System withComputer Workstation	R	R	R
Intra-Operative Software	R	R	R
Measurement System	R	R	R
Integrated Tool Support System	N/A	R	N/A
Floorstand Microscope System	R	N/A	N/A
FreeHand Tool Tracking System	O	O	R
R=RequiredO=OptionalN/A=Not Available

Model Configurations of LIGS System

Sections 20.4.1-20.4.6 provide an overview of each component of the LIGS System.

SECTION 21.4.1 SCOPEPLAN® IMAGING SYSTEM WITH COMPUTER WORKSTATION ·

Referring to Table 21.2, the Leksell® ScopePlan® Imaging System is a software based technology which provides surgical planning based upon Computer Tomography (CT), Magnetic Resonance Imaging (MRI), or other currently used 2D and 3D imaging techniques. ScopePlan® also provides for the retrieval of surgical planning studies and imaging during the surgical procedure, image correlation with a defined point (such as the microscope focus, probe tip, or instrument position and orientation), and image retrieval subsequent to the surgical procedure. ScopePlan® is to be used with specified commercially available surgical microscopes and accessories.

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ScopePlan® is supplied with a Hewlett-Packard C110 (or equivalent) computer running a Unix operating system. The Workstation includes a hard disk, a graphics board, and a high-resolution color monitor. A second computer Workstation may be installed in a separate location for pre-surgical review of patient images, and planning of the surgical intervention.

SECTION 21.4.2 INTRA-OPERATIVE SOFTWARE

All Models of LIGS allow the surgeon to proceed through the surgical intervention by analyzing images derived from the ScopePlan®, planning the surgical intervention, and then monitoring the intervention at a computer workstation in the Operating Room. The Intra-Operative Software allows the surgeon to display, manipulate, and process images from the ScopePlan®, and interact with the data electronically to derive corroborative information related to the specific anatomy of the patient. The software display is a menu-driven Graphical User Interface, which allows the surgeon to recall to the screen images and surgical trajectories created with ScopePlan®. Image tracking features of the software allow the surgeon to conduct measurement/calibration check of the FreeHand instruments, conduct registration of the patient anatomy to the ScopePlan® image datasets, and display the position and orientation of the FreeHand Instrument on the ScopePlan® images during the conduct of the surgical intervention.

SECTION 21.4.3 MEASUREMENT SYSTEM

The Measurement System is an infrared detection system, which is comprised of locators attached to the patient and tools, infrared detectors, a registration probe, and a processing unit. The locators and the probe contain infrared Light Emitting Diodes (LED's). The system accurately locates and continually tracks the patient, and simultaneously tracks the location of the tool of interest (microscope or FreeHand tool).

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SECTION 21.4.4 INTEGRATED TOOL SUPPORT SYSTEM

The Integrated Tool Support System (ITS) is a motorized, manually operated, computermonitored system that is mounted on the ceiling of the operating room. The ITS supports surgical tools, primarily a surgical microscope, during surgical procedure. The surgeon, or other medical professional, activates electromechanical components to position and adjust the microscope during surgery. The location of the microscope focus may be tracked and displayed on the ScopePlan® images. The ITS is the heart of the SurgiScope® Model of LIGS, and is only available with the SurgiScope® Model.

SECTION 21.4.5 FLOORSTAND MICROSCOPE SYSTEM

The Floorstand Microscope System is a manual floorstand with mounted microscope. The location of the microscope focus may be tracked and displayed on the ScopePlan® images. The ViewScope® Model of the LIGS System is provided with the floorstand microscope.

SECTION 21.4.6 FREEHAND TOOL TRACKING SYSTEM

The FreeHand Tool Tracking System consists of commercially available hand-held instruments, guides, and probes for cranial and spinal applications which are tracked by the Measurement System via locating devices (LED's) embedded in either the instrument handle, or a specially designed "tracker" attached to the instrument. This allows for the use of the existing Measurement System to localize the tip position and spatial orientation of the hand-held instruments. An interface with the ScopePlan® provides for visual feedback to the surgeon by displaying the instrument location as an image on the ScopePlan.

The FreeHand Tool Tracking System is designed as a component of the LIGS System for use with either the ViewScope® Mode or the SurgiScope® Model. Additionally, customers may desire the FreeHand surgical options without the use of a microscope. In

Confidential

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this event, the Freehand Tool Tracking System can be delivered as a separate Model of the LIGS System, without any microscope.

The modified LIGS System described in this Premarket Notification includes all of the safety features of the predicate device, as well as a number of additional safety features affiliated with the FreeHand Tool Tracking System.

INTENDED USE SECTION 21.5

The Leksell® Image Guidance Surgical System (LIGS) is intended for use in neurosurgical procedures to provide image guidance based on preoperative images which are visualized interactively with the aid of surgical tools.

TECHNOLOGICAL CHARACTERISTICS SECTION 21.6

The fundamental technical characteristics are similar to those of the predicate devices and are listed on the comparison chart provided in this 510(k) submission. Differences that exist between these systems relate to physical appearance and materials that do not affect the relative safety or effectiveness of the device.

SECTION 21.7 PERFORMANCE DATA

Validation and verification studies were conducted to evaluate the performance characteristics of the Leksell® Image Guidance Surgical System. The results of these studies demonstrated that the Leksell® Image Guidance Surgical System is capable of safely and accurately performing the stated intended use.

510(K) CHECKLIST SECTION 21.8

The Premarket Notification for the Leksell® Image Guidance Surgical System contains all the information required by 21 CFR 807.87. A completed copy of the Premarket Notification 510(k) Reviewer's Checklist is provided in the submission.

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CONCLUSIONS DRAWN FROM STUDIES SECTION 20.9

The results of performance testing demonstrate that the Leksell® Image Guidance Surgical System is capable of safely and accurately performing the stated intended use.

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Image /page/8/Picture/1 description: The image shows the seal of the Department of Health & Human Services - USA. The seal is circular and contains an emblem of an eagle with three lines representing its body. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged around the emblem.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

MAR 3 1 1998

Ms. Carol L. Patterson · Official Correspondent for Elekta AB c/o Patterson Consulting Group 18140 Smokesignal Drive San Diego, California 92630

Re: K973684 Elekta Leksell® Image Guidance Trade Name: Surgical System Requlatory Class: II Product Code: HAW January 15, 1998 Dated: January 20, 1998 Received:

Dear Ms. Patterson:

We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to 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, Druq, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual reqistration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with .... _ the current Good Manufacturing Practice requirement, as set forth in the Quality System Requlation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic (QS) inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP requlation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.

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Page 2 - Ms. Patterson

This letter will allow you to begin marketing your device as described in your 510 (k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4595. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html".

Sincerely yours,

Celia M. Witten, Ph.D., M.D. / Director Division of General and Restorative Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Elekta Instruments AB Response to 510(k) #K973684 Deficiencies January 15, 1998

K973684

INDICATIONS FOR USE

510(k) Number: To Be Assigned By FDA

Device Name: Elekta Leksell® Image Guidance Surgical System

Indications For Use: The Leksell® Image Guidance Surgical System (LIGS) is intended for use in cranial and spinal neurosurgical procedures to provide image guidance based on preoperative images which are visualized interactively with the aid of surgical tools.

PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED

Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)
Division of General Restorative Devices
510(k) Number	K973684

Prescription Use	✓	OR	Over-The-Counter Use
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(Per 21 CFR 801.109)

Regulation Number and Section

§ 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).