Abstract
Purpose: :
To develop a clinical prototype multimodal instrument based upon line scanning ophthalmoscopy (LSO) principles, and to evaluate the capabilities and performance of this device for management of retinal diseases.
Methods: :
The conceptual design approach of this multifunctional system was to integrate hardware for angiography with treatment beam delivery into a tracking scanning laser ophthalmoscope. The instrument includes an LSO imager, a retinal tracker and photodynamic therapy laser device on a compact slit lamp-mounted platform. The LSO imager was designed with sources and filters to detect standard ophthalmic dyes (fluorescein and indocyanine green). Fluorescence is detected with a single linear sensor, which has a 2:1 aspect ratio pixel size, and is configured to rapidly switch between near-infrared reflectance and fluorescence modes. The information from the imager was collected and processed with custom software for quantification of diagnostic information. The imager was tested on 10 subjects with various retinal diseases.
Results: :
The line scanning imager was able to resolve vessels with comparable resolution to standard fundus angiography system, with tolerable light intensities, and had lower signal-to-noise ratio than other standard clinical modalities. The automation software for detection and sizing of lesion was found to be comparable in detecting the lesion as compared to trained ophthalmologist. Retinal tracking was successful on all individuals tested, although tracking fidelity and performance of the blink relock algorithm was somewhat dependant on the retinal anatomy.
Conclusions: :
Our pilot study showed that this multimodal system has a potential to allow for rapid detection and treatment of retinal and choroidal abnormalities from a single platform.
Keywords: imaging/image analysis: clinical • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • image processing