Abstract
Purpose: :
To improve the data-collection efficiency of steerable adaptive optics scanning laser ophthalmoscope imaging by developing a clinical planning module (CPM). To evaluate the performance of the module by imaging retinal layers over large regions from healthy and diseased eyes.
Methods: :
We developed a software-based CPM which consists of two sub-modules: a navigation module and a montage acquisition module. The navigation module was developed by mapping the AOSLO to the SLO image from a Heidelberg Spectralis imager. The navigation module then guided the AOSLO beam to the desired place on the retina as indicated on the SLO image. The montage acquisition module systematically moved the AOSLO steering mirrors across the retina in a programmable predefined pattern. The CPM was tested on five normal healthy subjects and two patients. Each subject was imaged over a large region of either the retinal nerve fiber or photoreceptor layer. Accuracy was determined by the offset between the selected feature and the center of the AOSLO image. Repeatability was determined in two of the subjects by imaging the same regions over days.
Results: :
Within the range of +/-10 degree from the fixation target, the CPM could direct the AOSLO beam to the desired regions. The localization error on average was ~100um. With a frame size of 2.79°×1.78°(~800umx500um), a feature specified on the SLO image always appeared within the AOSLO video frame. On repeat trials the errors were of similar size. The montage acquisition module allowed rapid acquisition of contiguous montages. Although for subjects with poor fixation it sometimes required more time, in normal subjects the imaging of a 15 by 10 degrees montage could be completed in 15-30minutes. A 5 x 10 degree montage containing an identified defect from a patient was imaged in 15 minutes of patient time. The data acquisition efficiency was improved ~2x compared to that without the assistance of CPM.
Conclusions: :
We have implemented a clinical planning module to accurately guide the imaging beam to desired locations, and to quickly generate large-scale high resolution AOSLO montages. The approach is not only friendly for patients and clinicians, but also convenient for relating imaging data from different imaging platforms
Keywords: clinical (human) or epidemiologic studies: systems/equipment/techniques • clinical (human) or epidemiologic studies: systems/equipment/techniques • imaging/image analysis: clinical