July 1991
Volume 32, Issue 8
Free
Articles  |   July 1991
Feasibility of targeted drug delivery to selective areas of the retina.
Author Affiliations
  • Y Ogura
    Department of Ophthalmology, UIC Eye Center, University of Illinois, College of Medicine, Chicago 60612.
  • T Guran
    Department of Ophthalmology, UIC Eye Center, University of Illinois, College of Medicine, Chicago 60612.
  • M Shahidi
    Department of Ophthalmology, UIC Eye Center, University of Illinois, College of Medicine, Chicago 60612.
  • M T Mori
    Department of Ophthalmology, UIC Eye Center, University of Illinois, College of Medicine, Chicago 60612.
  • R C Zeimer
    Department of Ophthalmology, UIC Eye Center, University of Illinois, College of Medicine, Chicago 60612.
Investigative Ophthalmology & Visual Science July 1991, Vol.32, 2351-2356. doi:
  • Views
  • PDF
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Y Ogura, T Guran, M Shahidi, M T Mori, R C Zeimer; Feasibility of targeted drug delivery to selective areas of the retina.. Invest. Ophthalmol. Vis. Sci. 1991;32(8):2351-2356.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

A new method was developed to deliver locally a bolus dose of a drug to the retinal vasculature. The targeted delivery system was based on encapsulating the drug in heat-sensitive liposomes, which are injected intravenously and lysed in the retinal vessels by a heat pulse generated by a laser. To test if substances delivered in the vessels could also penetrate into the surrounding tissue, 6-carboxyfluorescein was encapsulated in liposomes and used as a marker for drug penetration. Moderate argon laser pulses were applied to the retinal vessels of Dutch pigmented rabbits to induce breakdown of the blood-retinal barrier (BRB). A suspension of liposomes at a dose of 2 ml/kg body weight, corresponding to a carboxyfluorescein dose of 12 mg/kg, was injected into the ear vein. The dye was released from the liposomes proximal to the damaged portion of the vessel. Fundus fluorescein angiograms were recorded with a video camera and digitized for subsequent image analysis. The penetration of carboxyfluorescein into the retinal tissue was evaluated by comparing the fluorescence intensity of the area around the damaged vessel with that of an adjacent control area. The dye penetration increased with the numbers of laser applications (P less than 0.001). The leakage was localized distally to the released site and was restricted to areas with a disrupted BRB. The mass of carboxyfluorescein that penetrated gradually spread with time. Both veins and arteries could be used for the targeted delivery. These results indicated that this delivery system, which is fully controllable by laser through the pupil, can deliver drugs inside the vasculature and into the retinal tissue wherever the BRB is disrupted.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×