Purchase this article with an account.
NR Boos, HA Elzembely, B Khoobehi; Enhanced Imaging of Corneal Neovascularization with High Spatial Resolution . Invest. Ophthalmol. Vis. Sci. 2002;43(13):1748.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To observe the detailed structure of corneal neovascularization in order to study the phenomenon of leukostasis in the cornea. Methods: Corneal neovascularization was induced in 12 eyes of 12 rats by placing two non-absorbable sutures in each cornea. Ten days later, all eyes were evaluated with sodium fluorescein (7, 14, or 21 mg/kg), indocyanine green (0.5, 1.0, 1.5, or 2.0 mg/kg), acridine orange (4 mg/kg) and infrared perchlorate (0.3 mg/kg) administered separately in different sessions via tail vein injection. Immediately after injection, and 10 and 20 minutes and 1 and 2 hours after injection, images were obtained using the SLO and a 60-diopter lens placed in the focal conjugate plane The images were recorded on digital video tape for later analysis. Results: All doses of both sodium fluorescein and indocyanine green showed leaky corneal vessels. The detailed microvascular network was visible using 1.5 and 2.0 mg/kg infrared perchlorate. A 1-mm diameter area of the vascular network was magnified to occupy the whole video screen. After 20 minutes, leukocytes were identified in the neovascular vessels and the tissue using the argon mode of the SLO to fluoresce leukocytes stained with acridine orange. Leukostasis was also visible 20 minutes after injection of infrared perchlorate using the IR mode of the SLO. The population of static leukocytes seen with this dye was larger than the population observed with acridine orange. This suggests that the infrared dye allows for visualization into deeper tissue layers. Twenty minutes after acridine orange injection, most of the visible fluorescent leukocytes were static; dynamic fluorescent leukocytes were not visible due to the blood column in the major vessels. With the infrared perchlorate dye, however, fluorescent leukocytes were observed in both the static and dynamic state. Conclusion: With this optical set up, high dose infrared perchlorate (3-4 times the recommended human dose) appears to provide enhanced high resolution images. Both acridine orange and infrared perchlorate could be used to study the leukostasis phenomenon in the corneal neovascular network; however, perchlorate can be used in an opaque cornea as well. In addition, perchloate can be used to calculate hemodynamic parameters of the cornea.
This PDF is available to Subscribers Only