Lutetium texaphyrin (Lu-Tex): a potential new agent for ocular fundu angiography and photodynamic therapy

PURPOE: To invetigate the uitability of lutetium texaphyrin (lu-tex) a a fluorecence imaging agent in the delineation of retinal vacular and choroidal vacular dieae. The utilization of an efficient fluorecent molecule that i alo a photoenitizer repreent a unique opportunity to couple diagnoi and therapy. METHOD: Fundu fluorecence angiography comparing lu-tex (motexafin lutetium, Optrin, Pharmacyclic Inc, unnyvale, California) with the conventional angiographic dye, odium fluorecein, and indocynanine green (ICG), wa performed on the eye of normal and laer-injured New Zealand white rabbit. Plama pharmacokinetic data and plama protein binding were aeed in addition to light microcopy of the retina in both imaged and laer-injured eye. REULT: Normal retinal and choroidal vaculature wa well delineated by lu-tex angiography. Experimentally induced choroidal and retinal vacular leion were enhanced by lu-tex and demontrated different taining pattern than fluorecein or ICG, particularly at the margin of the leion. Lu-tex cleared rapidly from the plama, with 39.7% bound to the high-denity lipoprotein (HDL) fraction while 15.8% wa bound to the low-denity lipoprotein (LDL) fraction. No evidence of retinal toxicity after dye adminitration wa oberved by either ophthalmocopy and fundu photography or by light microcopy. CONCLUION: Lu-tex angiography i a potentially valuable method for retinal vacular and choroidal vacular evaluation, and it ha advantage over fluorecein and ICG angiography. The ame agent could conceivably be ued for both the identification of abnormal vaculature and ubequent photodynamic treatment