Telepathology and Distant Telepathology and Distant Diagnosis with SMALL SIZE Diagnosis with SMALL SIZE

VIRTUAL SLIDES (SSVS)VIRTUAL SLIDES (SSVS)Eng. Marcano, Fco & Prof. Dr. O. Ferrer-Roca Eng. Marcano, Fco & Prof. Dr. O. Ferrer-Roca 20072007..

UNESCO Chair in TelemedicineUNESCO Chair in TelemedicineUniversity of La LagunaUniversity of La Laguna

Quality Control in Telemedicine - BiobankingQuality Control in Telemedicine - BiobankingCATAI - XVI Winter Course CATAI - XVI Winter Course

ULL - XXI Image Analisys CourseULL - XXI Image Analisys Course

http://www.teide.net/catai

ContentsContents• IntroductionIntroduction

• VSVS• SSVSSSVS

• SSVS quality assessmentSSVS quality assessment• ResultsResults• ConclusionsConclusions

Virtual SlidesVirtual Slides• Specimens converted to digital Specimens converted to digital

imagesimages

• Images are transmitted over Images are transmitted over networks, Internetnetworks, Internet

• Remote Analysis, Diagnosis, Remote Analysis, Diagnosis, teaching purposesteaching purposes © Telemedicine Research Group - University of Udine, Italy

Bone biopsyArea: 2.8x8.2 mm Pixels: about 290M

Virtual Slide Capture Virtual Slide Capture SystemsSystems

High power VS (40x) Image size in the order of Gigabytes

Expensive equipments50000€ - 250000€

Virtual Slides SizeVirtual Slides Size• Demands a Demands a

lot of lot of storagestorage

• JPEG based JPEG based imagesimages

20x 20x compressioncompression

© Department of Pathology. Clínica Universitaria. University of Navarra. Pamplona. Spain.

Virtual Slides Size - QCVirtual Slides Size - QC• Technique: Technique:

linear linear scanningscanning

• Image Image artifactsartifacts

• Equipment Equipment price vs. price vs. Image Image qualityquality

??

© Department of Pathology. Clínica Universitaria. University of Navarra. Pamplona. Spain.

Virtual Slides Size - QCVirtual Slides Size - QC• Good Good

AlignmentAlignment

© Department of Pathology. Clínica Universitaria. University of Navarra. Pamplona. Spain.

VS – High PowerVS – High Power Not always Not always

necessary necessary to have to have high-power high-power imagesimages

Images: Images: several several GigabytesGigabytes 1.3X 3.9X

11.1X 40X

e-Slidese-Slides• Telemedicine Research Group - University of Udine, ItalyTelemedicine Research Group - University of Udine, Italy

© Telemedicine Research Group - University of Udine, Italy

Technique: Technique: stitching of stitching of imagesimages

Cheaper Cheaper approachapproach

JPEG based JPEG based imagesimages

Size: still Size: still very largevery large

e-Slides - QCe-Slides - QC

© Telemedicine Research Group - University of Udine, Italy

Stitching of Stitching of images images

more image more image artifactsartifacts

e-Slides - QCe-Slides - QC

© Telemedicine Research Group - University of Udine, Italy

Problems Problems with image with image alignment alignment

Small Size Virtual Slides – Small Size Virtual Slides – SSVS©SSVS©

• Novel Technique Novel Technique

• Generates digital slides small in sizeGenerates digital slides small in size

• High resolution cameras (8-12 Mpx)High resolution cameras (8-12 Mpx)

• Excellent achromatic planapochromatic Excellent achromatic planapochromatic (infinite) optics(infinite) optics

SSVS© 2008

Small Size Virtual Slides – Small Size Virtual Slides – SSVS©SSVS©

• Uses Image-Compression format: JPEG2000 Uses Image-Compression format: JPEG2000 (ISO 15444-1, Wavelet)(ISO 15444-1, Wavelet)

• Take advantage of JPEG2000 Image format to Take advantage of JPEG2000 Image format to facilitate:facilitate:• navigation, navigation, • zooming,zooming,• transmission, transmission, • storagestorage

SSVS© 2008

JPEG2000JPEG2000• Created by the Created by the JJoint oint PPhotographic hotographic EExperts xperts GGroup roup

committee (2000)committee (2000)

• Intended to supersede discrete cosine transform-based Intended to supersede discrete cosine transform-based JPEG standard (1991)JPEG standard (1991)

• Standard Filename extension: Standard Filename extension: jp2 (ISO/IEC 15444-1 conforming files)jp2 (ISO/IEC 15444-1 conforming files)

jpx (Extended part-2 specifications or ISO/IEC 15444-2)jpx (Extended part-2 specifications or ISO/IEC 15444-2)

• Included in DICOM sup. 61 (Jan 2002)Included in DICOM sup. 61 (Jan 2002)

JPEG2000 Standard - JPEG2000 Standard - PartsParts

• Part 1, Core coding system (intended as royalty and license-fee free - NB NOT patent-free)

• Part 2, Extensions (adds more features and sophistication to the core)

• Part 3, Motion JPEG 2000 • Part 4, Conformance • Part 5, Reference software (Java and C implementations are

available) • Part 6, Compound image file format (document imaging, for pre-

press and fax-like applications, etc.) • Part 7 has been abandoned • Part 8, JPSEC (security aspects) • Part 9, JPIP (interactive protocols and API) • Part 10, JP3D (volumetric imaging) • Part 11, JPWL (wireless applications) • Part 12, ISO Base Media File Format (common with MPEG-4)

JPEG2000JPEG2000• Complex algorithm for compression / decompression takes a long Complex algorithm for compression / decompression takes a long

timetime

CompressedImage

decompression

SourceImage Color

Transformation Tiling WaveletTransform Quantization

Tier-1Encoder

(Modeling & Arithmetic

Coding)

Tier-2Encoder(Stream Creation)

RateControl

8 7 8 8 34 34 34 34

7 7 8 8 34 34 34 34

8 8 12 12 34 34 34 34

8 8 12 12 34 34 34 34

34 34 34 34 55 55 55 55

34 34 34 34 55 55 55 55

34 34 34 34 55 55 55 55

34 34 34 34 55 55 55 55

EBCOT - Embedded Block Coding with Optimal Truncation

JPEG2000JPEG2000• Higher compression ratios, images get blurredHigher compression ratios, images get blurred

570k 57k 6k 2k

JPEG2000JPEG2000Compression factor: 1:250Compression factor: 1:250Jpeg2000 - blurred Jpeg - blocked

Distant Diagnosis - Distant Diagnosis - TEXCAN©-IITEXCAN©-II

• TEXCAN-II® implements SSVS technique, allowing:

• Zoom-Focus©• Spatial resolution extreme digital zoom; • High quality focused image • Small size of compressed images• Fast & efficient distant consultation• Non-expensive digital virtual microscope

TEXCAN®-II Capture System

Intel 3.4 GHz Pentium® 4 /Intel® Core™2 Duo, 4 Gb RAM

CCD Camera 8Mpixels, firewire 1394.a

4x – 0.13 NA20x – 0.46 NA (ROI’s)

TEXCAN®-II Assessment Tools

Preparación Diagnóstico conocido Maligno Inflamación F.S.M.*

1

CITOLOGIA ORINA: Positivo para celulas malignas. Sugestivo de Carcinoma de celulas claras +

2

CITOLOGÍA ORINA: Citologia positiva para celulas tumorales malignas. Frotis sugestivo de Carcinoma. +

3

CITOLOGÍA DE LÍQUIDO PLEURAL. CITOLOGÍA SOSPECHOSA DE MALIGNIDAD. FROTIS CON INTENSA LINFOCITOSIS. + +

4

CITOLOGÍA DE LÍQUIDO PLEURAL: CITOLOGÍA POSITIVA PARA CÉLULAS TUMORALES MALIGNAS. Frotis sugestivo de Carcinoma. +

5

PUNCIÓN ASPIRACIÓN DE MAMA: Frotis sugestivos de mastopatía fibroquística con lesión epitelial proliferativa benigna intraquística.

6

CITOLOGÍA DE LAVADO PERITONEAL: CITOLOGÍA POSITIVA PARA CÉLULAS TUMORALES MALIGNAS. Frotis sugestivo de Carcinoma +

7

CITOLOGÍA DE LÍQUIDO PLEURAL: CITOLOGÍA SOSPECHOSA DE MALIGNIDAD. + +

8

Frotis con estimulo estrogenico mediano, algo inflamatorio, con espermatozoides, elementos cervicales asi como cambios celulares queratosicos y celulas pavimentosas con atipias nucleares moderadas. HSIL (High grade squamous intraepitelial lesion) + + +

9

Frotis pseudoluteal, algo inflamatorio, con elementos endocervicales sin anomalias. Hay cambios celulares queratosicos, asi como binucleaciones y elementos pavimentosos con atipias nucleares. LSIL-HPV? (Lesion escamosa intraepitelial de bajo grado-Human Papiloma Virus?) + +

10

Frotis mixto, moderadamente inflamatorio, con alteraciones celulares degenerativas, asi como escasos elementos pavimentosos con atipias ligeras, de probable origen reactivo. +

11

Estimulo estrogenico moderado, con citolisis, algo inflamatorio. Elementos cervicales bien conservados y escasos elementos pavimentosos con atipias ligeras. ASCUS (Atipical scamous cells of unknown significance). +

12

Estimulo estrogenico moderado, con citolisis, algo inflamatorio. Elementos cervicales bien conservados y celulas metaplasicas con atipias nucleares y algun pseudokoilocito, asi como cambios queratosicos. LSIL-HPV (Lesion escamosa intraepitelial de bajo grado-Human Papiloma Virus) +

13 Microcarcinoma papilar de tiroides. +14 Adenoma tubular15 Adenoma tubulovelloso

(*) F.S.M.: Fase secretora Menstrual+ : Positivo para el caso

JPIPJPEG2000

www.cataibreezee.ull.es:81.

V5.2

Samples Stat. Software

Viewer & Transmissione-forms

SSVS CaptureSSVS Capture• SSVS captured with the 4x objectiveSSVS captured with the 4x objective

• ROI’s (Region of Interest) selected by ROI’s (Region of Interest) selected by technician, captured with the 20x technician, captured with the 20x objectiveobjective

• Some clinical data included in each Some clinical data included in each SSVSSSVS

SSVS – samplesSSVS – samples• Small power Small power

enough for enough for having an having an image with image with diagnostic diagnostic qualityquality

53MB

68MB

7.8x 250x

1.6x 6.3x

Digital zoom 500x

6x3x

SSVS - samplesAreas identified by pathologist / technician

Random captured areas

26Mb 16Mb

40x40x

SSVS Samples

1Mb

8Mb

31.3x 42.5x

250x

250x

SSVS AssessmentSSVS Assessment• 10 pathologists, not trained in 10 pathologists, not trained in

TelepathologyTelepathology

• 3 pathologists, trained in 3 pathologists, trained in TelePathologyTelePathology

• 9 cytological/histological samples9 cytological/histological samples

Evaluation formEvaluation form

Results – ROC Results – ROC SSVS - Validity for diagnosis: SSVS - Validity for diagnosis:

• Area under the ROC curve of Area under the ROC curve of 0.95 p<0.0010.95 p<0.001, (good diagnostic quality), (good diagnostic quality)

Results - KappaResults - KappaConcordance and precision was high for Concordance and precision was high for

telepathology trained pathologiststelepathology trained pathologists• k=0.73, p<0.001k=0.73, p<0.001

• Concordance and precision was low for Concordance and precision was low for pathologists non-trained in telepathologypathologists non-trained in telepathology• low k=0.4, p<0.001low k=0.4, p<0.001

• Comments of the users where mainly Comments of the users where mainly devoted to improve the sampling area of devoted to improve the sampling area of the ROI.the ROI.

ConclusionsConclusions• The SSVS technique allows the technicians to The SSVS technique allows the technicians to

digitize a virtual slide easy to storage due to its digitize a virtual slide easy to storage due to its small size. small size.

• SSVS is perfectly suitable for discussion and SSVS is perfectly suitable for discussion and diagnosis at distance through intranet and diagnosis at distance through intranet and Internet providing a cheap digital microscope and Internet providing a cheap digital microscope and an online collaborative system. an online collaborative system.

• For specimens that require high power to make For specimens that require high power to make diagnosis, the SSVS+ROI technique has been diagnosis, the SSVS+ROI technique has been proved of value.proved of value.

Thanks!Thanks!