Figure 4From: Complementarity of ultrasound and fluorescence imaging in an orthotopic mouse model of pancreatic cancer Correlation of whole body fluorescence imaging and ultrasound imaging for assessment of tumor size in mice with orthotopic implants of fluorescently-labeled pancreatic tumor cells. Mice harboring tumors of varying sizes (n = 30) were imaged using both fluorescence and ultrasound imaging to assess tumor size. The resulting measurements (cross-sectional area in mm2, determined as previously explained) for each tumor were graphed to determine how well the imaging modalities correlated for assessment of tumor size over a range of tumor sizes. We assessed tumor sizes at two exposure times, 67 msec and 120 msec, that gave clear visual images which were neither under-exposed nor over-saturated and analyzed these images to measure tumor size. A-B. Determination of tumor size from fluorescence images taken with either a 67-millisecond exposure time (panel A) or a 120-millisecond exposure time (panel B). There is a strong correlation between fluorescence and ultrasound imaging modalities for assessment of tumor size over a range of tumor sizes at both exposure times. Both exposure times (67 msec and 120 msec) yielded similar values for R2 and P.Back to article page