Abstract
We are developing a new method of delivering substances locally and repeatedly in the retinal vasculature under external control. This delivery system is based on encapsulating the substance in heat-sensitive liposomes, which are injected intravenously and lysed by a heat pulse delivered by a laser. The feasibility of using this system with dyes and creating a sharp dye front was tested in vitro and in vivo. The results indicate that the background fluorescence of intact liposomes is minimal but in contrast a dramatic increase in fluorescence is achieved where the dye is released. In vivo tests indicated that only the selected vascular branch fluoresced. Moreover, a sharp dye front could be obtained repeatedly and preserved over significant distances. The presence of a sharp dye front allowed measurements, in vivo, of blood velocity which correlated well (r = 0.985, P<0.001) with the average blood velocity values calculated from the known flow rate.
Original language | English (US) |
---|---|
Pages (from-to) | 660-667 |
Number of pages | 8 |
Journal | Investigative Ophthalmology and Visual Science |
Volume | 30 |
Issue number | 4 |
State | Published - 1989 |
Externally published | Yes |
ASJC Scopus subject areas
- Ophthalmology
- Sensory Systems
- Cellular and Molecular Neuroscience