G laucoma A dvanced, LA bel-free H igh resolution A utomated OCT D - - PowerPoint PPT Presentation

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Project Overview G laucoma A dvanced, LA bel-free H igh resolution A utomated OCT D iagnostics GALAHAD Jul-2017 This project has received funding from the European Union's Horizon 2020 www.galahad-project.eu research and innovation

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www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Project Overview

Glaucoma – Advanced, LAbel-free High resolution Automated OCT Diagnostics GALAHAD

Jul-2017

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SLIDE 2

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

  • Project key facts
  • Motivation
  • Project objectives
  • Project technology
  • Photonic sources
  • Components and sub-systems
  • Automated algorithms
  • Demonstration
  • Summary

Page 2

Presentation outline

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SLIDE 3

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

  • Project key facts
  • Motivation
  • Project objectives
  • Project technology
  • Photonic sources
  • Components and sub-systems
  • Automated algorithms
  • Demonstration
  • Summary

Page 3

Presentation outline

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SLIDE 4

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

GALAHAD key facts

  • Horizon 2020 project funded by the European Union
  • ICT-29-2016: Photonics KET
  • Project No. 732613
  • Budget: c. 4 M€
  • Ten partners
  • 4 four industrial, 3 academic, 2 clinical, 1 management
  • Start date: 01-Dec-2016
  • Duration: 36 months
  • Coordinator: Gooch & Housego (Torquay)
  • Project public website: www.galahad-project.eu

Page 4

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SLIDE 5

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Consortium

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Optical components and sub-systems for OCT [Coordinator] OCT systems integrator Supercontinuum sources Diffraction gratings and spectrometers Supercontinuum source design and simulation Algorithm development Data collection (new lab data) and analysis Data collection (existing patient data) and analysis Data collection (existing patient data) and analysis Project management and admin Main role in project Partner

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SLIDE 6

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

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Presentation outline

  • Project key facts
  • Motivation
  • Project objectives
  • Project technology
  • Photonic sources
  • Components and sub-systems
  • Automated algorithms
  • Demonstration
  • Summary
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SLIDE 7

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

  • Glaucoma is the second leading cause of

blindness globally (after cataracts)

  • Increased intra-ocular pressure
  • Slow onset and gradual degeneration
  • Irreversible damage to the optic nerve head
  • Universal screening could save 4M cases of

blindness p.a. worldwide

  • Cost-effective testing is not possible with existing

technology

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Motivation: potential for glaucoma screening

Vertical transfoveal OCT of an eye with epiretinal fibrosis

Image courtesy of Rigshospitalet (Copenhagen)

OCT

  • A candidate screening technology is optical coherence tomography
  • Offers non-contact label-free high-resolution retinal imaging

BUT…technical developments are required for glaucoma screening

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SLIDE 8

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 8

Presentation outline

  • Project key facts
  • Motivation
  • Project objectives
  • Project technology
  • Photonic sources
  • Components and sub-systems
  • Automated algorithms
  • Demonstration
  • Summary
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SLIDE 9

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 9

UHR-PS OCT

  • Ultra-high resolution (UHR-) OCT
  • Leading commercial systems achieve c. 3-5 µm axial resolution
  • Glaucoma screening requires an axial resolution of c. 1 µm

This requires broader bandwidth source and components

  • Polarisation sensitive (PS-) OCT
  • Can identify birefringent retinal features
  • These may improve glaucoma diagnosis

This requires polarisation maintaining (PM) components

GALAHAD hardware objective To develop ultra-high resolution polarisation sensitive OCT

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SLIDE 10

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 10

Automated algorithms

  • Automated image analysis based on artificial intelligence
  • Could allow cost-effective glaucoma screening
  • Intelligent algorithms will be developed useable by non-experts
  • Automatically process and analyse OCT images
  • Identification of patients requiring closer expert examination

GALAHAD software objective Automated algorithms to identify high risk patients from OCT images

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SLIDE 11

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 11

Presentation outline

  • Project key facts
  • Motivation
  • Project objectives
  • Project technology
  • Photonic sources
  • Components and sub-systems
  • Automated algorithms
  • Demonstration
  • Summary
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SLIDE 12

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Supercontinuum sources

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  • Pulsed fibre lasers are coupled with

supercontinuum (SC) generating fibres

  • Allows fibre delivery of output spectrum
  • Broadband light from UV to near-IR
  • In GALAHAD, NKT will develop two

different sources:

  • 1. Low risk option
  • To ensure project delivery
  • Randomly

polarised, low noise, incoherent SC source

  • 2. High risk option
  • New state-of-the-art source
  • Linearly

polarised, ultra-low noise, coherent SC source

1 2 3 4 5 6 450 550 650 750 850 950 1050 1150 1250 1350 1450 1550 1650 1750 power [mW/nm] wavelength [nm] Extreme Red P=500mW

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www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

SC sources (SCSs) competition

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  • The resolution of an OCT system depends largely on the spectral

bandwidth of the interrogating source

  • SCSs can comfortably provide sufficient optical power across the 600-

900 nm window suitable for ocular OCT

  • Other options:
  • Lamps: brightness is too low for OCT
  • SLD* and ASE† sources have relatively narrow bandwidths
  • Ti:sapphire lasers are large, expensive and not rugged enough
  • Swept sources mainly access the 1300 nm band
  • The noise level of the OCT source is a critical consideration in the

GALAHAD project:

  • Ti:sapphire and the incoherent SCS can provide similar results
  • Coherent SCSs provide the lowest possible noise for any OCT

technology.

* Super Luminescent Diode † Amplified Spontaneous Emission

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SLIDE 14

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

State-of-the-art SCSs

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  • New SCSs are pumped with all-

normal dispersion fibre.

  • This produces temporally coherent

pulses

  • Temporal coherence reduces shot-

to-shot noise

  • Background noise of OCT

measurement is reduced

  • Linearly polarised SCSs allow for

polarisation sensitive OCT

  • New image information available
  • n birefringent objects and features
  • Features (like “blebs”) can be
  • bserved

Figure shows the strong birefringence of

  • blebs. (a) Intensity OCT, (b) polarisation-

sensitive OCT, and (c) highly birefringent regions from (b) overlaid on (a).

The normally-pumped, linearly polarised, ultra-low noise, coherent SCS is the best available source for OCT.

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SLIDE 15

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Femtosecond laser sources available at DTU

Laser description Max. Average power/ W Pulse length/ fs Rep rate/ MHz Wavelength/ nm OCT viability

Picosecond mode-locked laser compressed with a hollow-core fiber 1 255 80 1036 Yes, but max SC band: 800- 1300 nm Fianium femtosecond laser (Commercially available) 5 170 80 1064 Yes Max SC band 650-1450 nm Optical parametric amplifier 0.23 250 21 1064 No (bulky) Measured supercontinua from 1 m (red) and 9 m (black) fibre Calculated (dashed red) with 100 kW and 170 fs pumped at 1064 nm Inset: Microscope image of the ANDi (all normal dispersion) fibre. Bandwidth (black) from 950 nm at -10 dB w.r.t. 800 nm vs average power measured at the fiber

  • utput.

Estimated average power (blue) from 650-950 nm. Pumping with 170 fs at 1064 nm.

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www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613. Calculated spectrally averaged RIN (relative intensity noise) for different pulse lengths along 1 m of fiber. Pumping along the slow-axis with 170 fs at 1064 nm and 44 kW peak power. LB is the optical wave breaking distance.

1. With the current configuration (ANDi fiber and 170 fs, 80 MHz), high average powers are needed to reach 650 nm. 2. Simulations taking into account the two polarizations of the fundamental mode show that pumping along the slow-axis of the ANDi fiber, the RIN is low for short fs pulses even for high power and long fiber length. 3. Simulations and experiments show that noise increases for higher pump powers, when the fiber is NOT pumped along the slow axis.

Measured (squares/solid) and calculated (stars/dashed) RIN for different output average powers using 170 fs at 1064 nm. The calculated RIN is for pumping at 20° ° ° ° w.r.t. slow axis.

Conclusions on pump options

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SLIDE 17

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 17

Presentation outline

  • Project key facts
  • Motivation
  • Project objectives
  • Project technology
  • Photonic sources
  • Components and sub-systems
  • Automated algorithms
  • Demonstration
  • Summary
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SLIDE 18

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 18

Diffraction gratings

  • Ibsen core technology is planar, surface relief

transmission gratings in fused silica

  • Produced by holographic or photo-lithographic

patterning and reactive ion etching

  • In GALAHAD Ibsen will work to develop its

fundamental grating technology:

  • Cost-effective grating manufacturing process
  • Large, high efficiency broadband transmission
  • Polarisation insensitive
  • GALAHAD targets:
  • Large area gratings
  • Low PDL (polarisation dependent loss)
  • >90% diffraction efficiency
  • 300 nm bandwidth
  • Low grating volume pricing
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SLIDE 19

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

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Spectrometers

  • Ibsen strengths in spectrometer manufacture
  • In-house transmission gratings
  • Robust and athermal design
  • High throughput
  • Flexibility for OEM integration
  • In GALAHAD the objective is a low cost

polarisation insensitive broadband spectrometer

  • GALAHAD spectrometer targets:
  • High performance, high resolution
  • Temporally stable, broadband
  • <1800 cm3 for UHR-OCT
  • Low volume pricing
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SLIDE 20

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Fused component development

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  • Development of beyond state-of-the-art fused couplers
  • Cost effective and rugged components
  • Suitable for Ultra High Resolution (UHR-) & Polarisation Sensitive (PS-OCT)
  • Specific advances in wavelength-flattened SM & PM couplers
  • Target bandwidth: SM & PM

300 nm

  • Target flatness:

SM ±5% PM ±10%

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SLIDE 21

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Wideband Optical Delay Line

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  • An optical delay line is used in

OCT systems to match the reference and sample optical path lengths

  • For optimum performance, the

delay line needs to be dynamically adjusted

  • Allows for changes in eye

position between patients

  • New design of small form factor

motorised optical delay lines

  • Wideband PM device
  • High stability and reliability over

travel and temperature

  • Low loss
  • 80 mm/s travel with <10 µm

resolution

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SLIDE 22

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 22

Presentation outline

  • Project key facts
  • Motivation
  • Project objectives
  • Project technology
  • Photonic sources
  • Components and sub-systems
  • Automated algorithms
  • Demonstration
  • Summary
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SLIDE 23

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Algorithm development

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  • Development of retinal layer segmentation algorithms
  • Initially based on conventional OCT images
  • Image processing algorithms for significant feature extraction
  • Refinement and testing from new data acquired in GALAHAD
  • GALAHAD target:
  • Development and validation of a glaucoma screening algorithm
  • Automatic, robust and clinically usable
  • “Traffic light” output to identify high risk patients for further assessment

OCT image

Automated feature extraction

Processed image Assessment

Automated image analysis

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SLIDE 24

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Algorithm development

Page 24

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SLIDE 25

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 25

Presentation outline

  • Project key facts
  • Motivation
  • Project objectives
  • Project technology
  • Photonic sources
  • Components and sub-systems
  • Automated algorithms
  • Demonstration
  • Summary
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SLIDE 26

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

  • Development
  • f

test standards including cellular, tissue and animal models for UHR OCT performance analysis and demonstration

  • Data collection from test standards

and animal models for algorithm training and demonstration

  • Experimental

characterization

  • f
  • ptical tissue properties utilizing OCT

and digital holographic microscopy

  • Characterization
  • f

tissue birefringence properties with polarization sensitive interferometric techniques

Data collection and demonstration

Tissue refractive index maps with corresponding cross-sections (mouse model, ex vivo) OCT tomographic image of a cellular 3D test standard OCT image of a 3D artificial model including different tissue layers

200 µm

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SLIDE 27

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Demonstration

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  • Establish two independent UHR-PS-OCT systems
  • Evaluate on acquired and inherited small animal glaucoma models
  • GALAHAD targets:
  • Reduced screening costs (cf. current cost of ~300€)
  • “Traffic light” algorithm response to alert physicians to potential glaucoma.

Spectrometer Supercontinuum source Reference arm & fibre optics Alignment, control, and data acquisition

Hardware Software & analysis Lab demo

Test demo system 2 Test demo system 1 Big data analysis Machine learning and algorithm training

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SLIDE 28

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 28

Presentation outline

  • Project key facts
  • Motivation
  • Project objectives
  • Project technology
  • Photonic sources
  • Components and sub-systems
  • Automated algorithms
  • Demonstration
  • Summary
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SLIDE 29

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 29

Project Summary

  • Glaucoma is the second leading cause of blindness globally
  • Universal screening could save 4M cases of blindness p.a. worldwide
  • Ultra-high resolution OCT is a key candidate screening technology
  • Polarisation sensitive OCT could offer new information to clinicians
  • UHT PS OCT requires
  • Very broadband polarised sources: SCS
  • Very broadband polarisation maintaining delay lines and components
  • Automated algorithms could assess OCT images
  • Traffic light output to indicate high risk patients for further testing
  • Demonstration on rodents to be performed at two hospital laboratories
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SLIDE 30

www.galahad-project.eu

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 732613.

Page 30

Thank you for your attention!! www.galahad-project.eu Technical enquiries Liam Henwood-Moroney Gooch and Housego (Torquay) lhenwood-moroney@goochandhousego.com Other enquiries Bruce Napier Vivid Components bruce@vividcomponents.co.uk