DIAGNOSIS and management of hydatid liver cysts have been hampered in the past by the lack of a simple method of visualizing liver tumors. Recently, photoscanning of the liver with rose bengal I 131 or colloidal gold Au 198 has permitted visualization of liver tumors by a simple atraumatic technique. Case reports of two patients are presented to emphasize the value of hepatic photoscanning in the diagnosis and management of this condition. Report of Cases Case 1.— A 31-year-old Greek woman had resided in the US for six years. She was admitted to the University of Michigan Medical Center in March, 1961. History disclosed bouts of self-limited right upper quadrant pain radiating to the flank and scapula unaccompanied by other gastrointestinal symptoms. Pain occurred in exacerbations over a six-year period, gradually becoming more frequent. Scleral icterus first appeared in 1958 and was noted occasionally over the next two years. In