Purchase this article with an account.
DX Hammer, RD Ferguson, JC Magill, AF Elsner, RH Webb; Tracking Scanning Laser Ophthalmoscope (TSLO): Initial Human Subject Testing . Invest. Ophthalmol. Vis. Sci. 2002;43(13):4373.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: The effectiveness of image stabilization with a third-generation retinal tracker in a compact scanning laser ophthalmoscope was demonstrated in initial human subject tests. Methods: A retinal tracking system was incorporated into a compact scanning laser ophthalmoscope. The retinal tracking system uses a confocal reflectometer with a closed loop optical servo system to lock onto features in the fundus. New optical hardware features in the third generation tracker include dual wavelength detection, integrated monochromator, higher-order motion control, and stimulus source. The system software consists of a feedback control algorithm and a user interface. Software enhancements include automatic bias correction, asymmetric feature tracking, image averaging, and acquisition and logging of compressed images and streaming video files. Normal adult subjects were tested without mydriasis to optimize the tracking instrumentation and to characterize imaging performance. Results: The third generation retinal tracking system achieved a bandwidth of greater than 1 kHz (equivalent to 3000 deg/sec for disc tracking). This bandwidth greatly exceeds the maximum rate of motion of the human eye (500 deg/sec). The TSLO system stabilized images in all test subjects during ordinary saccades at several hundred degrees per second. Feature lock was maintained for minutes despite subject eye blinking. Successful frame averaging allowed image acquisition with decreased noise in low-light applications. Conclusion: The retinal tracking system significantly enhances the imaging capabilities of the scanning laser ophthalmoscope. Additional clinical and research applications in development and/or testing include perimetry, angiography, stabilized multifocal ERG displays, endogenous fluorescence and photoreceptor imaging.
This PDF is available to Subscribers Only