← Product Code [QKQ](/submissions/PA/subpart-d%E2%80%94pathology-instrumentation-and-accessories/QKQ) · K241273 # FullFocus (K241273) _Paige.Ai, Inc. · QKQ · Jan 9, 2025 · Pathology · SESE_ **Canonical URL:** https://fda.innolitics.com/submissions/PA/subpart-d%E2%80%94pathology-instrumentation-and-accessories/QKQ/K241273 ## Device Facts - **Applicant:** Paige.Ai, Inc. - **Product Code:** [QKQ](/submissions/PA/subpart-d%E2%80%94pathology-instrumentation-and-accessories/QKQ.md) - **Decision Date:** Jan 9, 2025 - **Decision:** SESE - **Submission Type:** Traditional - **Regulation:** 21 CFR 864.3700 - **Device Class:** Class 2 - **Review Panel:** Pathology - **Attributes:** Software as a Medical Device ## Indications for Use FullFocus is a software intended for viewing and management of digital images of scanned surgical pathology slides prepared from formalin-fixed paraffin embedded (FFPE) tissue. It is an aid to the pathologist to review, interpret and manage digital images of pathology slides for primary diagnosis. FullFocus is not intended for use with frozen sections, cytology, or non-FFPE hematopathology specimens. It is the responsibility of a qualified pathologist to employ appropriate procedures and safeguards to assure the quality of the images obtained and, where necessary, use conventional light microscopy review when making a diagnostic decision. FullFocus is intended to be used with the interoperable components specified in the below Table. ## Device Story FullFocus is a web-based software-only device for viewing/managing digitized pathology images (WSI) from FFPE tissue; inputs are DICOM, SVS, or NDPI files from FDA-cleared scanners (Leica Aperio GT 450 DX or Hamamatsu NanoZoomer S360MD). Software converts images into Paige TIFF format using WebP or AVIF compression; maintains fidelity to original images. Pathologist uses browser (Chrome/Edge) to open cases, pan, zoom, measure, and annotate images for primary diagnosis. Device facilitates clinical decision-making by providing digital visualization as an alternative to conventional light microscopy. Operates in clinical pathology environments; requires qualified pathologist to perform quality control and verify slide presence/staining against LIS data. Benefits include efficient digital workflow for primary diagnosis. ## Clinical Evidence Bench testing only. No clinical data. Pixel-wise comparison testing performed on 30 H&E-stained FFPE slides across 6 configurations. 180 image-pairs per configuration were compared using CIEDE2000 (ΔE00) metric; all results showed 95th percentile ΔE00 < 3, confirming identical reproduction to predicate IRMS. Turnaround time testing confirmed load/pan/zoom times met acceptance criteria (<10s load, <7s render). Measurement accuracy testing confirmed length and area measurements matched reference values exactly. ## Technological Characteristics Web-based software-only device; supports DICOM, SVS, and NDPI file formats. Uses WebP (quality 85, method 4) and AVIF (quality 70, 4:4:4 subsampling) compression. Operates on standard PC hardware (min 4GB RAM, 1.6GHz CPU) via web browsers (Chrome/Edge). Connectivity via network (10 Mbps). No specific hardware materials; relies on interoperable displays (Dell/JVC-Kenwood). Software-only; no mechanical/energy-based components. ## Regulatory Identification The whole slide imaging system is an automated digital slide creation, viewing, and management system intended as an aid to the pathologist to review and interpret digital images of surgical pathology slides. The system generates digital images that would otherwise be appropriate for manual visualization by conventional light microscopy. ## Special Controls A whole slide imaging system must comply with the following special controls: (1) Premarket notification submissions must include the following information: (i) The indications for use must specify the tissue specimen that is intended to be used with the whole slide imaging system and the components of the system. (ii) A detailed description of the device and bench testing results at the component level, including for the following, as appropriate: (A) Slide feeder; (B) Light source; (C) Imaging optics: (D)Mechanical scanner movement; (E) Digital imaging sensor; (F) Image processing software; (G)Image composition techniques; (H)Image file formats; (I) Image review manipulation software; (J) Computer environment; (K)Display system. (iii)Detailed bench testing and results at the system level, including for the following, as appropriate: (A)Color reproducibility; (B) Spatial resolution; (C) Focusing test; (D) Whole slide tissue coverage; (E) Stitching error: (F) Turnaround time. (iv) Detailed information demonstrating the performance characteristics of the device, including, as appropriate: (A)Precision to evaluate intra-system and inter-system precision using a comprehensive set of clinical specimens with defined, clinically relevant histologic features from various organ systems and diseases. Multiple whole slide imaging systems, multiple sites, and multiple readers must be included. (B) Reproducibility data to evaluate inter-site variability using a comprehensive set of clinical specimens with defined, clinically relevant histologic features from various organ systems and diseases. Multiple whole slide imaging systems, multiple sites, and multiple readers must be included. (C) Data from a clinical study to demonstrate that viewing, reviewing, and diagnosing digital images of surgical pathology slides prepared from tissue slides using the whole slide imaging system is non-inferior to using an optical microscope. The study should evaluate the difference in major discordance rates between manual digital (MD) and manual optical (MO) modalities when compared to the reference (e.g., main sign-out diagnosis). (D) A detailed human factors engineering process must be used to evaluate the whole slide imaging system user interface(s). (2) Labeling compliant with 21 CFR 809.10(b) must include the following: The intended use statement must include the information described in paragraph (i) (1)(i) of this section, as applicable, and a statement that reads, "It is the responsibility of a qualified pathologist to employ appropriate procedures and safeguards to assure the validity of the interpretation of images obtained using this device." (ii) A description of the technical studies and the summary of results, including those that relate to paragraph (1)(ii) and (1)(iii) of this section, as appropriate. (iii) A description of the performance studies and the summary of results, including those that relate to paragraph (1)(iv) of this section, as appropriate. (iv) A limiting statement that specifies that pathologists should exercise professional judgment in each clinical situation and examine the glass slides by conventional microscopy if there is doubt about the ability to accurately render an interpretation using this device alone. *Classification.* Class II (special controls). The special controls for this device are:(1) Premarket notification submissions must include the following information: (i) The indications for use must specify the tissue specimen that is intended to be used with the whole slide imaging system and the components of the system. (ii) A detailed description of the device and bench testing results at the component level, including for the following, as appropriate: (A) Slide feeder; (B) Light source; (C) Imaging optics; (D) Mechanical scanner movement; (E) Digital imaging sensor; (F) Image processing software; (G) Image composition techniques; (H) Image file formats; (I) Image review manipulation software; (J) Computer environment; and (K) Display system. (iii) Detailed bench testing and results at the system level, including for the following, as appropriate: (A) Color reproducibility; (B) Spatial resolution; (C) Focusing test; (D) Whole slide tissue coverage; (E) Stitching error; and (F) Turnaround time. (iv) Detailed information demonstrating the performance characteristics of the device, including, as appropriate: (A) Precision to evaluate intra-system and inter-system precision using a comprehensive set of clinical specimens with defined, clinically relevant histologic features from various organ systems and diseases. Multiple whole slide imaging systems, multiple sites, and multiple readers must be included. (B) Reproducibility data to evaluate inter-site variability using a comprehensive set of clinical specimens with defined, clinically relevant histologic features from various organ systems and diseases. Multiple whole slide imaging systems, multiple sites, and multiple readers must be included. (C) Data from a clinical study to demonstrate that viewing, reviewing, and diagnosing digital images of surgical pathology slides prepared from tissue slides using the whole slide imaging system is non-inferior to using an optical microscope. The study should evaluate the difference in major discordance rates between manual digital (MD) and manual optical (MO) modalities when compared to the reference ( *e.g.,* main sign-out diagnosis).(D) A detailed human factor engineering process must be used to evaluate the whole slide imaging system user interface(s). (2) Labeling compliant with 21 CFR 809.10(b) must include the following: (i) The intended use statement must include the information described in paragraph (b)(1)(i) of this section, as applicable, and a statement that reads, “It is the responsibility of a qualified pathologist to employ appropriate procedures and safeguards to assure the validity of the interpretation of images obtained using this device.” (ii) A description of the technical studies and the summary of results, including those that relate to paragraphs (b)(1)(ii) and (iii) of this section, as appropriate. (iii) A description of the performance studies and the summary of results, including those that relate to paragraph (b)(1)(iv) of this section, as appropriate. (iv) A limiting statement that specifies that pathologists should exercise professional judgment in each clinical situation and examine the glass slides by conventional microscopy if there is doubt about the ability to accurately render an interpretation using this device alone. ## Predicate Devices - Aperio GT450X ([K232202](/device/K232202.md)) - NanoZoomer S360MD Slide scanner system ([K213883](/device/K213883.md)) ## Submission Summary (Full Text) > This content was OCRed from public FDA records by [Innolitics](https://innolitics.com). If you use, quote, summarize, crawl, or train on this content, cite Innolitics at https://innolitics.com. > > Innolitics is a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices, including [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/). {0} FDA U.S. FOOD & DRUG ADMINISTRATION # 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ## I Background Information: A 510(k) Number K241273 B Applicant Paige.AI, Inc. C Proprietary and Established Names FullFocus D Regulatory Information | Product Code(s) | Classification | Regulation Section | Panel | | --- | --- | --- | --- | | QKQ | Class II | 21 CRF 864.3700 – Whole slide imaging system | PA - Pathology | ## II Submission/Device Overview: A Purpose for Submission New device B Type of Test: Software only device ## III Intended Use/Indications for Use: A Intended Use(s): See Indications for Use below. B Indication(s) for Use: For In Vitro Diagnostic Use Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993-0002 www.fda.gov {1} FullFocus is a software intended for viewing and management of digital images of scanned surgical pathology slides prepared from formalin-fixed paraffin embedded (FFPE) tissue. It is an aid to the pathologist to review, interpret and manage digital images of pathology slides for primary diagnosis. FullFocus is not intended for use with frozen sections, cytology, or non-FFPE hematopathology specimens. It is the responsibility of a qualified pathologist to employ appropriate procedures and safeguards to assure the quality of the images obtained and, where necessary, use conventional light microscopy review when making a diagnostic decision. FullFocus is intended to be used with the interoperable components specified in the below Table. Table: Interoperable Components of FullFocus | Scanner Hardware | Scanner Output file format | Interoperable Displays | | --- | --- | --- | | Leica Aperio GT 450 DX scanner | DICOM, SVS | Dell UP3017 Dell U3023E | | Hamamatsu NanoZoomer S360MD Slide Scanner | NDPI | Dell U3223QE JVC-Kenwood JD-C240BN01A | C Special Conditions for Use Statement(s): Rx - For Prescription Use Only IV Device/System Characteristics: A Device Description: FullFocus, version 2.29, is a web-based software-only device that facilitates the viewing and navigating of digitized pathology images of slides prepared from FFPE tissue specimens acquired from FDA cleared digital pathology scanners on FDA cleared displays as specified in the intended use Table above. FullFocus renders these digitized pathology images for review, management, and navigation for pathology primary diagnosis. Image acquisition is performed using the intended scanner(s), with the operator conducting quality control on the whole-slide images according to the scanner's instructions for use and lab specifications to determine if re-scans are needed. Once a whole slide image is acquired using the intended scanner and becomes available in the scanner's database file system, a separate medical image communications software (not part of the device) automatically uploads the image and its corresponding metadata to persistent cloud storage. Integrity checks are performed during the upload to ensure data accuracy. The WSIs undergo intentional compression and are converted into standardized Paige TIFF files when visualized in FullFocus, as shown in Table below. Testing was conducted to ensure that the compressed images maintain fidelity to their original images. K241273 - Page 2 of 10 {2} Table 1. WSIs Compression when Visualized in FullFocus | Scanner Hardware | Scanner Output File Format | Compression Methods | | --- | --- | --- | | Leica Aperio GT 450 DX scanner | DICOM | FullFocus uses the WebP image format, configured with quality 85 and method 4 | | | SVS | FullFocus uses the AVIF image format, configured with quality 70 and 4:4:4 subsampling | | Hamamatsu NanoZoomer S360MD Slide scanner | NDPI | FullFocus utilizes the AVIF image file format compression which is tailored with settings configured to quality 70 and subsampling 4:4:4 | The subject device enables the reading pathologist to open a patient case, view the images, and perform actions such as zooming, panning, measuring distances and areas, and annotating images as needed. After reviewing all images for a case, the pathologist will render a diagnosis. The computer environment for during the use of FullFocus is specified in the Table below: Table 2. Computer Environment/System Requirements | Environment | Component | Minimum Requirements | | --- | --- | --- | | Hardware | Processor | 1 CPU, 2 cores, 1.6 GHz | | | Memory | 4 GB RAM | | | Network | Bandwidth of 10 Mbps | | Software | Operating System | Windows macOS | | | Browser | Google Chrome (129.0.6668.90 or higher) Microsoft Edge (129.0.2792.79 or higher) | # B Instrument Description Information: 1. Instrument Name: FullFocus 2. Specimen Identification: The FullFocus device utilizes digital pathology images acquired from Hematoxylin and Eosin (H&E) stained glass slides using the Leica Aperio GT 450 DX scanner or the Hamamatsu NanoZoomer S360MD Slide scanner. A reading pathologist selects a case (patient) from an external worklist, and the subject device retrieves the corresponding images from external image storage. The scanned images are identified using the specimen identifier previously assigned to the case. 3. Specimen Sampling and Handling: Specimen sampling and handling are conducted independently and prior to the use of the subject device. This process involves obtaining biopsy or resection specimens, which are K241273 - Page 3 of 10 {3} then processed using standard histology techniques. After H&E staining of the FFPE tissue sections, digital images are generated from the glass slides using the Leica Aperio GT 450 DX Scanner, or the Hamamatsu NanoZoomer S360MD Slide scanner. 4. Calibration: Not applicable 5. Quality Control: The subject device receives whole-slide images from the Paige image storage system. All WSI files are quality-controlled and acquired in accordance with the scanner's instructions for use. The subject device incorporates specific quality control measures to ensure the accuracy and completeness of the images. Each pathologist must perform quality checks prior to analyzing pathology images using the subject device. This includes verifying that all scanned slide images have been successfully imported. For each case, the pathologist should review the thumbnails in the pathology image window to confirm that all required slides are present. Additionally, the tissue block and staining information should be manually verified against data from the Laboratory Information System (LIS). V Substantial Equivalence Information: A Predicate Device Name(s): Aperio GT450X; NanoZoomer S360MD Slide scanner system B Predicate 510(k) Number(s): K232202; K213883 C Comparison with Predicate(s): K241273 - Page 4 of 10 {4} | Device & Predicate Device(s): | K241273 | | | K232202 | | | K213883 | | --- | --- | --- | --- | --- | --- | --- | --- | | Device Trade Name | FullFocus | | | Aperio GT450X | | | NanoZoomer S360MD Slide scanner system | | General Device Characteristic Similarities | | | | | | | | | Intended Use /Indications For Use | For In Vitro Diagnostic Use FullFocus is a software intended for viewing and management of digital images of scanned surgical pathology slides prepared from formalin-fixed paraffin embedded (FFPE) tissue. It is an aid to the pathologist to review, interpret and manage digital images of pathology slides for primary diagnosis. FullFocus is not intended for use with frozen sections, cytology, or non-FFPE hematopathology specimens. It is the responsibility of a qualified pathologist to employ appropriate procedures and safeguards to assure the quality of the images obtained and, where necessary, use conventional light microscopy review when making a diagnostic decision. FullFocus is intended to be used with the interoperable components specified in the below Table. Table: Interoperable components of FullFocus | | | The Aperio GT 450 DX is an automated digital slide creation and viewing system. The Aperio GT450 DX is intended for in vitro diagnostic use as an aid to the pathologist to review and interpret digital images of surgical pathology slides prepared from formalin-fixed paraffin embedded (FFPE) tissue. The Aperio GT 450 DX is for creation and viewing of digital images of scanned glass slides that would otherwise be appropriate for manual visualization by conventional light microscopy. Aperio GT 450 DX is comprised of the Aperio GT 450 DX scanner, which generates images in the Digital Imaging and Communications in Medicine (DICOM) and in the ScanScope Virtual Slide (SVS) file formats, the Aperio WebViewer DX viewer, and the displays. The Aperio GT 450 DX is intended to be used with the interoperable components specified in Table 1. Table 1: Interoperable components of Aperio GT 450 DX | | | The NanoZoomer S360MD Slide scanner system (“NanoZoomer System”) is an automated digital slide creation, viewing, and management system. The NanoZoomer System is intended for in vitro diagnostic use as an aid to the pathologist to review and interpret digital images of surgical pathology slides prepared from formalin-fixed paraffin embedded (“FFPE”) tissue. The NanoZoomer System is not intended for use with frozen section, cytology, or non-FFPE hematopathology specimens. The NanoZoomer System comprises the NanoZoomer S360MD Slide scanner, the NZViewMD Software and the JVC Kenwood JD-C240BN01A display. The NanoZoomer System is for creation and viewing of digital images of scanned glass slides that would otherwise be appropriate for manual visualization by conventional light microscopy. It is the responsibility of a qualified pathologist to employ appropriate procedures and safeguards to assure the validity of the interpretation of images obtained using NanoZoomer System. | | | Scanner Hardware | Scanner Output file format | Interoperable Displays | Scanner Hardware | Scanner Output file format | Interoperable Viewing Software | Interoperable Displays | | | Leica Aperio GT 450 DX scanner | DICOM, SVS | Dell UP3017 Dell U3023E Dell U3223QE JVC Kenwood JD-C240BN01A | Aperio GT 450 DX scanner | SVS | Aperio WebViewer DX | Barco MDPC-8127 Dell UP3017 Dell U3023E Dell U3223QE | | | Hamamatsu NanoZoomer S360MD Slide scanner | NDPI | | Aperio GT 450 DX scanner | DICOM | Sectra Digital Pathology Module (3.3) | Dell U3223QE | | | | | | The Aperio GT 450 DX is not intended for use with frozen section, cytology, or non-FFPE hematopathology specimens. It is the responsibility of a qualified pathologist to employ | | | | K241273 - Page 5 of 10 {5} K241273 - Page 6 of 10 | | | appropriate procedures and safeguards to assure the validity of the interpretation of images obtained using the Aperio GT 450 DX. | | | --- | --- | --- | --- | | Principle of Operation | After WSI images are successfully acquired by using Aperio GT 450 DX scanner, or Hamamatsu NanoZoomer S360MD Slide scanner, the WSI images are stored in the cloud. During review, the pathologist opens WSI images from storage, perform further QC and reads WSI images of the slides to make a diagnosis. | The Aperio GT 450 DX is a WSI system. The technician places the slides into the Aperio GT 450 DX scanner. The Aperio GT 450 DX scanner automatically loads the slides, takes the micro images, finds the tissues, and scans the slides. The scanner also automatically performs quality control (QC) and notifies the user of any image quality issue during the image acquisition. The image data is sent to end-user-provided image storage attached to the local network. During the review, the pathologist opens WSI images acquired with the WSI scanner from the image storage, performs further QC, and reads WSI images of the slides to make a diagnosis. | The NanoZoomer S360MD Slide scanner system (“NanoZoomer System”) is an automated digital slide creation, viewing, and management system. The NanoZoomer System is intended for in vitro diagnostic use as an aid to the pathologist to review and interpret digital images of surgical pathology slides prepared from formalin-fixed paraffin embedded (“FFPE”) tissue. The NanoZoomer System is not intended for use with frozen section, cytology, or non-FFPE hematopathology specimens. The system’s embedded image processing software is responsible for image acquisition and the processing of individual tiles prior to image composition or stitching. Hamamatsu’s NZAcquireMD software organizes all WSI tiles into a single NDPi file, which is a proprietary file format. During the review, the pathologist opens the WSI on the NZViewMD software to render a diagnosis. | | Specimen Type | Digitized surgical pathology slides prepared from FFPE tissue | Same | Same | | Type of Software Application | Internet browser-based application | Same | PC-based installed application | | Image Manipulation and Review Functions | Panning, zooming, annotations, and measurements | Same | Functions for continuous panning and zooming, annotations, distance/area measurements, track visited areas, export images, discrete Z-axis displacement, and display of diagnostic status of images. | | **General Device Characteristic Differences** | | | | | Device Components | FullFocus image viewing software | WSI scanner (Aperio GT450 DX scanner), Image Management System (Aperio WebViewer DX image viewing software), Display | WSI scanner (NanoZoomer S360MD Slide scanner), Image Management System (NZViewMD), Display | | Diagnostic Image File Format | Leica SVS and DICOM, Hamamatsu NDPI | Leica SVS and DICOM | Hamamatsu NDPI | | End User’s Interface | FullFocus | Aperio WebViewer DX for Leica SVS, Sectra Digital Pathology Module (3.3) for Leica SVS and DICOM | NZViewMD | {6} VI Standards/Guidance Documents Referenced: 1. FDA Guidance “Technical Performance Assessment of Digital Pathology Whole Slide Imaging Devices”. April 20, 2016. 2. FDA Guidance “Applying Human Factors and Usability Engineering to Medical Devices”. February 3, 2016. 3. FDA Guidance “Content of Premarket Submissions for Device Software Functions”. June 14, 2023. 4. FDA Guidance “Cybersecurity in Medical Devices: Quality System Considerations and Content of Premarket Submissions”. September 27, 2023. 5. AAMI TIR 45:2012 - Guidance on the use of AGILE practices in the development of medical device software. 6. IEC 62304 Edition 1.1 2015-06 CONSOLIDATED VERSION, 13-79. Medical device software – Software life cycle processes. 7. ISO 14971 Third Edition 2019-12, 5-125, Medical devices – Applications of risk management to medical devices. VII Performance Characteristics (if/when applicable): A Analytical Performance: 1. Precision/Reproducibility: Not applicable 2. Linearity: Not applicable 3. Analytical Specificity/Interference: Not applicable 4. Accuracy (Instrument): Not applicable 5. Carry-Over: Not applicable B Other Supportive Instrument Performance Characteristics Data: Technical performance testing was conducted with the subject device, FullFocus as specified below. 1. Bench Testing - Pixelwise comparison test FullFocus supports multiple file formats, multiple browsers, and multiple displays, constituting various configurations to be tested. Pixel-wise comparison testing to demonstrate identical image reproduction was conducted to compare WSIs reproduced by the subject device and the comparators as listed in Table 3 below. The subject device was compared to the predicate device’s image review manipulation software (IRMS, as defined in FDA K241273 - Page 7 of 10 {7} guidance document, "Technical Performance Assessment of Digital Pathology Whole Slide Imaging Devices" dated April 20, 2016) using the quantitative pixel-wise comparison method. The basis for the comparison was the CIEDE2000 color difference equation, $\Delta E00$ . The devices were tested as operating with the intended components, including the scanner, specific file format, image management systems (subject device with the intended browsers, comparator [predicate device IRMS]) and displays, as specified in the Table 3 below. For each of the 6 configurations in Table 3 below, the device was tested with multiple slides across multiple regions of interest (ROI) at multiple magnification levels, on multiple displays. A total of $30\mathrm{H}\&\mathrm{E}$ -stained, FFPE glass slides of normal and tumor tissues from various human anatomical organs were used in the testing. For each configuration, the glass slides were scanned on a corresponding intended scanner to obtain 30 WSIs. For each of the 30 WSIs, 3 ROIs from different locations were selected by qualified personnel to represent various features in the tissue samples. Each ROI was captured at 2 magnification levels $(10x, 40x)$ . The screenshots were captured for each of the intended display while viewing with the subject device and predicate device IRMS. The screenshots were cropped and registered to be pixelwise comparable. The cropped image included most of the pixels in the image except for those in the viewer-specific user interface areas. For each configuration and each intended display, two sets of images were collected: comparator (predicate device IRMS) and the subject device (FullFocus with the intended browser). Each image set included 180 images that covered all combinations of 30 slides, 3 ROIs and 2 magnification levels. The testing data, including the overview images of the 30 glass slides with annotations of the ROIs, registration/cropping information, and captured images, were provided in the FDA specific format. The above procedure was repeated for each corresponding intended display. The comparator (predicate device IRMS) image set was used as the reference to compare the subject device image set to determine whether all the 180 image-pairs were identical for each configuration and each intended display. Two images are considered identical if the 95th percentile of the pixelwise differences, computed using the International Commission on Illumination (CIE) color difference metric CIEDE2000 ( $\Delta$ E00), is less than 3 $\Delta$ E00. Testing results showed that the pixelwise differences across all 180 image-pairs per configuration and per intended display were less than 3 $\Delta$ E00. The maximum (max), minimum (min), and mean of the 95th percentile $\Delta$ E00 value were reported in Table 3. Testing results demonstrated that WSIs reproduced by FullFocus are identical to images reproduced by the predicate devices. Table 3. FullFocus Pixelwise Comparison Testing Results | Scanner | Image File Format | Subject Device/ Browser | Comparator (Predicate device IRMS /Browser) | Displays | Results | | --- | --- | --- | --- | --- | --- | | Leica Aperio GT450DX scanner | DICOM | FullFocus /Chrome | Sectra UniView /Chrome | • Dell UP3017 • Dell U3023E • Dell U3223QE | max (95th percentile ΔE00) = 2.95 min (95th percentile ΔE00) = 1.61 mean (95th percentile ΔE00) = 2.44 | | | | FullFocus /Edge | Sectra UniView /Edge | | max (95th percentile ΔE00) = 2.95 min (95th percentile ΔE00) = 1.61 | K241273 - Page 8 of 10 {8} K241273 - Page 9 of 10 ## 2. Turnaround Time The turnaround times of the subject device were measured for the operations of image opening, panning, and zooming for different scenarios. Below acceptance criteria was used: - < 10 seconds to load first image in FOV across all images - < 7 seconds to render the Field of View (FOV) while zooming and panning across all images Test results for different scenarios met the test acceptance criteria and showed acceptable turnaround time for the intended use of the subject device. Table 4. FullFocus Turnaround Time Testing Results | Scanner | Image File Format | Subject Device/Browser | Turnaround Time Results | | --- | --- | --- | --- | | Leica Aperio GT 450 DX scanner | DICOM | • FullFocus/Chrome • FullFocus/Edge | The overall median load time (sec) for first image is 1.63, for panning is 0.93 and zooming is 1.86. | | | SVS | • FullFocus/Chrome • FullFocus/Edge | The overall median load time (sec) for first image is 1.68, for panning is 1.03 and zooming 2.00. | | Hamamatsu NanoZoomer S360MD Slide scanner | NDPI | • FullFocus/Chrome • FullFocus/Edge | The overall median load time (sec) for first image is 2.27, for panning is 0.84 and zooming is 1.45. | ## 3. Measurement – distance and area The length and area measurement accuracy of the subject device was tested across multiple magnification levels. An image of a calibration scale slide with known object sizes was used to verify the measurement accuracy. A series of annotations were created to cover different orientations and different magnification levels in 4 intended browsers. The differences between the actual and reported measurements were calculated for each annotation. The acceptance criteria were as follows: 1) The 1 mm measured line should match the reference {9} value exactly 1 mm ± 0mm and 2). The measured area must match the reference area exactly 0.2 x 0.2 mm for a total of 0.04 mm² ± 0 mm². Test results showed that the subject device performed accurate measurements of length and area and all line and area measurements compared to the reference value were exactly the same with no error, across multiple magnification settings with respect to its intended use. ## 4. Human Factor (Usability) Testing Human factors study designed around critical user tasks and use scenarios performed by representative users were conducted for previously cleared FullFocus, version 1.2.1, in K201005, per FDA guidance “Applying Human Factors and Usability Engineering to Medical Devices (2016)”. Human factors validation testing is not necessary as the user interface and workflow remain unchanged. ## VIII Proposed Labeling: The labeling supports the finding of substantial equivalence for this device. ## IX Conclusion: The submitted information in this premarket notification is complete and supports a substantial equivalence decision. K241273 - Page 10 of 10 --- **Source:** [https://fda.innolitics.com/submissions/PA/subpart-d%E2%80%94pathology-instrumentation-and-accessories/QKQ/K241273](https://fda.innolitics.com/submissions/PA/subpart-d%E2%80%94pathology-instrumentation-and-accessories/QKQ/K241273) **Published by [Innolitics](https://innolitics.com)** — a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices. If you're preparing [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/), [get in touch](https://innolitics.com/contact). **Cite:** Innolitics at https://innolitics.com