Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - GALAHAD (Glaucoma – Advanced, LAbel-free High resolution Automated OCT Diagnostics)

Teaser

The project GALAHAD targets the critical need for better glaucoma diagnostic systems. Glaucoma is an agerelatedmajor cause of blindness. The eye disease is characterized by an irreversible damage to the optic nerve headcaused by increased intra-ocular pressure. The current...

Summary

The project GALAHAD targets the critical need for better glaucoma diagnostic systems. Glaucoma is an agerelated
major cause of blindness. The eye disease is characterized by an irreversible damage to the optic nerve head
caused by increased intra-ocular pressure. The current screening and basic diagnostics for the disease involve intraocular
pressure measurement, visual field tests and detection of structural damage to the optic nerve head and
retinal nerve fibre layer. The present methods have high rates of false positive or false negative results since the in
depth analysis of optical nerve head damage is not possible due to the poor resolution of available optical
technologies. A leading candidate is optical coherence tomography (OCT), but the required axial resolution is ~1
μm, well beyond the 3-5 μm resolution of commercial systems. GALAHAD aims to develop a label free, compact
and easy to operate high resolution diagnostic OCT system. The multiband and multimodal system will use
submicron ultra-high resolution polarisation sensitive OCT (UHR PS OCT). The key breakthrough elements are: (i)
A revolutionary low cost multiband supercontinuum light source. (ii.) Ground-breaking ultra-broadband photonic
components required to exploit such a source. (iii.) Automated glaucoma screening algorithms: using end user
evaluation of cell and animal models and tissue samples, automated algorithms will be developed, trained and
tested so that non-expert operators will be able to perform glaucoma screening. The GALAHAD in depth glaucoma
diagnostics after a positive screening with conventional methods will dramatically reduce false positive and false
negative screening results and decrease the number of patients suffering from glaucoma-related disability. The
project is driven by world leading companies and manufacturers of OCT systems and guided by requirement
specifications and validated by high ranking clinical and experimental ophthalmologists in their clinical settings.

Work performed

GALAHAD has had a very successful first Period.

From a top level technical perspective, the project has made steady progress towards all of the “breakthrough elements”:

i) A revolutionary low cost multiband supercontinuum light source.
The polarised SCS has significantly exceeded expectations and noise reduction work is going well.


ii) Ground-breaking ultra-broadband photonic components required to exploit such a source.
To date the broadband components have all been developed beyond expectations, including the delivery of a new fusion rig for coupler components and delay line, spectrometer and grating designs. New state-of-the-art couplers (both PM and SM) and delay lines have already been fabricated. The grating work is progressing well, with high expectations for a low lost large area process.


iii) Automated glaucoma screening algorithms: using end user evaluation of cell and animal models and tissue samples, automated algorithms will be developed, trained and tested so that non-expert operators will be able to perform glaucoma screening.
Close interaction between the software and medical partners has resulted in delivery of the first feature extraction algorithms, including agreement on OCT scanning protocols and segmentation methodology. The database framework is in place including both human and rodent samples, and this will be extended throughout the project.

Final results

GALAHAD has set the new state-of-the-art in several different technical areas.

-The polarised SCS has extremely good polarisation extinction ratio and has performed excellently on lifetime test. Details will be published by NKT and DTU shortly.

-Gooch and Housego has fabricated extremely wideband polarisation maintaining and singlemode fused couplers for both tap and 50/50 splitter functionality. Details to be released shortly.

-Gooch and Housego has designed and build singlemode optical delay lines which set the new state-of-the-art in terms of size, speed and bandwidth. Products are under discussion. Details to be released shortly.


In the second half of the project, the consortium will GALAHAD will develop the first integrated ultra-high resolution polarisation sensitive OCT systems that will extend the state-of-the-art:
-a robust all-fibre UHR-PS-OCT system with c. 1 μm resolution
-20-fold noise reduction permits a 200 kHz scan rate to enable anterior & posterior segment imaging

Website & more info

More info: http://www.galahad-project.eu.