Daniel Palanker: Photonic solutions promise to restore vision
Daniel Planker is Associate Professor, Department of Ophthalmology and Hansen Experimental Physics Laboratory at Stanford University. His group studies interactions of electric fields with biological cells and tissues in a broad range of frequencies -- from quasi-static to optical, and develops their medical (primarily ophthalmic) applications.
In 2005 Palanker and associates developed a new method of retinal photocoagulation using a Pattern Scanning Laser (PASCAL). In this approach patterns of multiple pulses are applied during the eye-fixation time (under half a second), with pulse durations in the range of 10-30 ms. In addition to much faster and less painful delivery of the laser treatment, PASCAL enabled the computer-guided sub-visible treatments and sparked renewed interest in research on photocoagulation. PASCAL is currently in clinical use worldwide, and this approach is replicated by all major manufacturers of retinal lasers.
Using this laser system they discovered that retinal healing in highly confined laser lesions dramatically differs from that of conventional retinal burns. For these lighter lesions, not only can the inner retina be spared, but photoreceptors migrating into the damaged zone from unaffected areas can restore photoreceptor-layer continuity over time, as opposed to formation of permanent scars in the conventional lesions. This way retinal scotomas and scarring can be avoided, thereby ameliorating many side effects of laser photocoagulation, and allowing for re-treatment. Palanker studies the mechanisms of retinal response to thermal injury, associated neural plasticity, and its effects on retinal signal processing.
The lab also works on minimally traumatic approaches to retinal laser therapy using microsecond exposures to a rapidly scanning laser, and utilizing the effects of retinal plasticity and sub-lethal hyperthermia. They also work on automated and diagnostic image-guided ocular laser therapies with applications to the retina, glaucoma and cataracts.