AbstractFifty consecutive cystic renal masses in 43 patients were evaluated by both static scanning and real‐time scanning techniques. Various parameters were evaluated and compared to ascertain whether the strict static scan cystic criteria were always present in comparable real‐time evaluations. Four (8%) of the 50 masses were not classic cysts on real‐time examinations, although the criteria were present on the static scans. Two had minimal acoustic enhancement and two had low‐intensity internal echoes. Possible reasons for this difference were detailed and discussed. The potential problems in this observation were enumerated. Based on these observations, in certain cases when a cystic renal mass demonstrates poor acoustic enhancement or low‐level internal echoes in real‐time examination, static scanning may be helpful and may obviate the need for furt