Table 1.
Technical details of the portable ultrasound unit (PUS) and the fully-equipped clinical ultrasound unit (FCUS).
Table 2.
Equations of each method for calculating the thyroid volume.
Figure 1.
Ultrasound measurement of the maximum transverse dimension of the dolphin thyroid gland (TS_MAX).
Top left picture shows the position of the transducer at the neck region. Top right picture shows the schematic diagram of the thyroid gland in a dorsal orientation with the straight line representing the position of the transducer. Bottom image shows a transverse grey scale sonogram of the thyroid gland of a bottlenose dolphin. Note the maximum transverse dimension of the thyroid gland is measured (calipers +).
Figure 2.
Ultrasound measurement of the longitudinal dimension of the dolphin thyroid gland at the midline (LS_MID).
Top left picture shows the position of the transducer at the neck region. Top right picture shows the schematic diagram of the thyroid gland in a dorsal orientation with the straight line representing the position of the transducer. Bottom image shows a longitudinal grey scale sonogram of the thyroid gland of a bottlenose dolphin. Note the dorsoventral dimension (calipers x), the craniocaudal dimension (calipers +) and the cross-sectional area (dotted line) are measured respectively.
Figure 3.
Ultrasound measurement of the maximum longitudinal dimension of the left thyroid lobe of a dolphin (LS_L).
Top left picture shows the position of the transducer at the neck region. Top right picture shows the schematic diagram of the thyroid gland in a dorsal orientation with the straight line representing the position of the transducer. Bottom image shows a longitudinal grey scale sonogram of the left thyroid lobe of a bottlenose dolphin. Note the maximum longitudinal dimension of the left thyroid lobe is demonstrated, and the dorsoventral dimension (calipers x), the craniocaudal dimension (calipers +) and the cross-sectional area (dotted line) are measured respectively. The same ultrasound measurement of the maximum longitudinal dimension was repeated on the right thyroid lobe.
Figure 4.
Ultrasound measurement of the maximum longitudinal dimension of the right thyroid lobe of a dolphin (LS_R).
Top left picture shows the position of the transducer at the neck region. Top right picture shows the schematic diagram of the thyroid gland in a dorsal orientation with the straight line representing the position of the transducer. Bottom image shows a longitudinal grey scale sonogram of the right thyroid lobe of a bottlenose dolphin. Note the maximum longitudinal dimension of the right thyroid lobe is demonstrated, and the dorsoventral dimension (calipers x), the craniocaudal dimension (calipers +) and the cross-sectional area (dotted line) are measured respectively.
Figure 5.
Ultrasound measurement of the long axis of the left thyroid lobe of a dolphin.
Top left picture shows the position of the transducer at the neck region. Top right picture shows the schematic diagram of the thyroid gland in a dorsal orientation with the straight line representing the position of the transducer. Bottom image shows an oblique grey scale sonogram of the left thyroid lobe of a bottlenose dolphin. Note the long axis of the left thyroid lobe is measured (calipers +).
Figure 6.
Ultrasound measurement of the maximum cross-sectional area of the left thyroid lobe of a dolphin.
Top left picture shows the position of the transducer at the neck region. Top right picture shows the schematic diagram of the thyroid gland in a dorsal orientation with the straight line representing the position of the transducer. Bottom image shows an oblique grey scale sonogram of the left thyroid lobe of a bottlenose dolphin. Note the maximum cross-sectional area of the left thyroid lobe is demonstrated, and the dorsoventral dimension (calipers x), the mediolateral dimension (calipers +) and the cross-sectional area (dotted line) are measured respectively.
Table 3.
Inter-equipment variability of the ultrasound thyroid linear and cross-sectional area measurements.
Table 4.
Intra-operator (repeatability) variability of the ultrasound thyroid linear and cross-sectional area measurements.