POSITRON PROBE FOR CORNEAL TUMOR BIOASSAY

RECENTLY, PRELIMINARY RESEARCH USING CYCLOTRON-PRODUCED, POSITRON-EMITTING RADIOLABELS HAS BEEN CONDUCTED AT THE MEMORIAL SLOAN-KETTERING CANCER CENTER TO DEVELOP A RABBIT/RAT CORNEAL IMPLANT METHOD TO STUDY HUMAN TUMOR ANGIOGENESIS AND METABOLISM. THIS TECHNIQUE IS DESIGNED TO DETERMINE THE DIRECT IMPACT OF CHEMOTHERAPEUTIC STRATEGIES ON HUMAN BRAIN TUMORS. IT IS HOPED THAT DRUG SCREENING FOR PATIENTS WITH GLIOMAS CAN BE CARRIED OUT WITH SUFFICIENT EFFICACY TO ACHIEVE A SUBSTANTIAL INCREASE IN THE LONG-TERM SURVIVAL RATE OF SUCH PATIENTS. TO DEVELOP SUCH A PROTOCOL, UNIQUE EQUIPMENT IS NEEDED TO MEASURE THE ACCUMULATION OF POSITRON-LABELED AMINO ACIDS WITHIN THE TUMOR WITH HIGH SENSITIVITY AND SPATIAL RESOLUTION DESPITE THE PRESENCE OF AN EXTREMELY LARGE BACKGROUND FROM THE ASSOCIATED 511-KEV GAMMA RAYS. THIS PROGRAM WILL DEVELOP A SMALL, SOLID-STATE, DUAL-ELEMENT POSITRON GAMMA PROBE SPECIFICALLY DESIGNED FOR USE WITH THE POSITRON-EMITTING ISOTOPES CENTRAL TO THE DEVELOPMENT OF THIS BIOASSAY. SUCH A LOW-COST, NONIMAGING SYSTEM THAT WILL ALLOW HIGH-QUALITY MEASUREMENTS OF METABOLIC INDICES FOR BASIC AND APPLIED MEDICAL RESEARCH WILL BE A USEFUL ADDITION TO THE CAPABILITIES OF MEDICAL CYCLOTRON GROUPS.