Multi-modal AO-LSO Phase Gradient Imaging of the Inner Retina

Project Summary Abstract Physical Sciences IncPSIis continuing the pursuit of new clinical applications and advanced multimodal capabilities for its novel retinal imaging technology based on an adaptive optics line scanning ophthalmoscopeAO LSOThe Compact Adaptive Optics Retinal ImagerCAORIeliminates high speed scanning componentsreduces the clinical footprint compared to research adaptive optics scanning laser ophthalmoscopesAOSLOand simplifies AO optical design while preserving the confocal advantageIn the proposed Phase II programPSI will incorporate a powerful new modality for phase gradient imagingPGIin the inner retinaCAORI originally emphasized line confocal imaging of photoreceptors in the outer retina in the bright field reflectance modeHoweverin recent yearsfollowing the groundbreaking work of AOSLO researchersso calleddark fieldand split detection AOSLO modalities with various combinations of offset detection apertures allow very subtle phase objects to be indirectly imaged in relatively transparent retinal layersincluding microvasculature and neural somascell bodies of retinal ganglion cellsfor exampleSuch features can used for early identification of new biomarkers in neurovascular and neurodegenerative conditions such as diabetic retinopathy and glaucomaIn Phase IPSI has proven that CAORI can be adaptedwithin the same general line confocal paradigm and footprintfor directsensitivemulti aperture phase gradient imagingPGIin the inner retinaIn particulara time domain integrationTDIline camera enables line confocality of the AO LSO to be broadly adjustedincreasing collection aperture swithout loss of image resolutionmor light sensitivitySimultaneous bright field confocal ophthalmoscopy and a new type of oblique backilluminated line ophthalmoscopy for directly imaging inner retinal layers in transmission was demonstrated on a single focal planeDifferencing pairs of inner retinal focused TDI imagesand videoswith complementary line offsets produces phase gradient images the line field AO LSO equivalent of split detection AOSLOPSI will modify existing CAORI beta prototypes for PGI and begin clinical testing of these system in collaboration with researchers at New York Eye and Ear InfirmaryMount Sinaidiabetic retinopathyand NYU Langone Medical CenterglaucomaProject NarrativeThe clinical rationale for advanced high resolution imaging technology is rapidly evolvingPowerful new in vivo AO modalities can now provide important fundamental insights at the cellular level into many disease processes in the nearly transparent inner retina such as diabetic retinopathy and glaucomaThe development of novel therapies including gene therapy for a number of diseases in the coming years will be an important driver of market need for high resolution imagingBy the time secondary inflammatory processes are fully engageddamage associated with late stage disease is easy to see but more difficult to addressnew therapies will be deployed at the earliest stages when disease is still confined to specific cells and layers