Figure 1.

Conventional ultrasonography of VX2 tumors in rabbits. (A) At 14 days after tumor inoculation, 2-D ultrasonography showed homogeneous internal hypoechoes (calipers) in VX2 tumors with clear contour. (B) At 21 days after tumor inoculation, 2-D ultrasonography showed hypoechoes in tumors with clear contour and irregular anechoic areas (calipers) with stripped septate echoes. (C) At 21 days after tumor inoculation, color Doppler energy imaging showed blood flow signals in the peripheral regions and irregular blood branches inside the VX2 tumors.