HIGH RADIATION EXPOSURE IN SPACE IS A CRITICAL CHALLENGE INHIBITING US FROM EXPLORING DEEP SPACE AND PURSUING LONG-DURATION MISSIONS AS CURRENT MEDICAL SYSTEMS ARE UNABLE TO MONITOR DIAGNOSE OR TREAT CANCER WITHIN PHYSICAL SPACECRAFT CONSTRAINTS AND COMMUNICATION LIMITS. ULTRASOUND IS THE CURRENT IMAGING SYSTEM USED ON THE INTERNATIONAL SPACE STATION BUT ITS AMBIGUOUS IMAGES REQUIRE TELEMEDICAL SUPPORT FOR DIAGNOSIS MAKING IT AN IMPRACTICAL SOLUTION FOR DEEP SPACE. MINIMALLY INVASIVE CANCER TREATMENTS ARE BEING DEVELOPED BUT THESE RELY ON OTHER METHODS TO LOCATE AND DIAGNOSE THE TUMOR. ELECTRICAL IMPEDANCE TOMOGRAPHY (EIT) IS A NON-INVASIVE NON-IONIZING TECHNOLOGY THAT PRODUCES IMAGES OF THE ELECTRICAL PROPERTIES OF TISSUES ALLOWING FOR EARLY CANCER DETECTION AND THE MONITORING OF OTHER LONG-TERM PHYSIOLOGICAL EFFECTS OF SPACE TRAVEL (E.G. TISSUE INJURY MUSCLE ATROPHY THORACIC FUNCTION CELL GROWTH). TO ADDRESS THE NEEDS DESCRIBED IN TECHNICAL AREA 6.3.1 WE PROPOSE A MULTI-CHANNEL EIT ACQUISITION SYSTEM TO MONITOR AND DIAGNOSE THE PHYSIOLOGICAL EFFECTS OF DEEP SPACE TRAVEL WITH THE ABILITY TO PLUG IN DIFFERENT PROBES FOR DIFFERENT APPLICATIONS. DURING THE FIRST YEAR WE WILL COUPLE ULTRASOUND AND EIT (US-EIT) TO PROVIDE A LOW-COST LOW-RESOURCE MEDICAL IMAGING SYSTEM THAT CAN ACCURATELY DISCRIMINATE BETWEEN MALIGNANT AND BENIGN TUMORS WHILE MEETING SPACE TRAVEL CONSTRAINTS ELUCIDATING THE EFFECTS OF DEEP SPACE RADIATION EXPOSURE AND PROVIDING GREATER DIAGNOSTIC ACCURACY FOR SELECTING THE MOST APPROPRIATE TREATMENT. WE WILL DEMONSTRATE PROOF-OF-CONCEPT OF USEIT FOR CANCER DETECTION WITH THREE AIMS: DESIGN THE HARDWARE REQUIRED FOR AN INTEGRATED US-EIT PROBE ASSESS AND VALIDATE US-EIT CAPABILITIES IN CANCER PATIENTS AND DEVELOP A PLAN FOR DEPLOYING THE MULTI-CHANNEL EIT SYSTEM IN DEEP SPACE. IN THE FOLLOWING YEARS WE WILL OPTIMIZE THE US-EIT HARDWARE FOR DEEP SPACE DEPLOYMENT AND CONDUCT LARGER CLINICAL TRIALS TO REFINE FULL-BODY IMAGING CAPABILITIES OF THE US-EIT MODALITY.