Fig. 1

Sagittal ultrasonographic images of the tongue ventral surfaces in three of five healthy calves (a-c), and the affected case (d). a,b Normal ventral lingual structures exhibit 1) muscular layers in which the echogenic muscular fibers are regularly aligned, 2) two hyperechoic lines, which include homogenous hypoechoic structure, and 3) the deep lingual artery running along the distal hyperechoic line. Lingual structures deeper than the hyperechoic lines disappear due to a reverberation artifact. Rich blood flow is noted in the deep lingual artery on the Color-flow Doppler ultrasonograms. VMT: ventral muscular thickness. DSA: distance between the ventral surface of the tongue and the deep lingual artery. WD: width of the colored region on Doppler image of the deep lingual artery. c Blood flow is weakened into the deep lingual artery, but is comparatively rich in the intramuscular vessels on the Color-flow Doppler ultrasonogram. d The ventral lingual muscular layers are thicker than that of the normal tongue, but retains the regular alignment of the echogenic muscular fibers. Blood flow is not evident into the deep lingual artery on the Color-flow Doppler ultrasonogram. Scale: 10 mm