this study was conducted to determine the use of three-dimensional ultrasonography (3du) in ocular imaging of the dog and measuring of its optical axis. 12 healthy mixed-breed dogs including 6 males and 6 females were studied. 3du of the eyes were done using a 5–12 mhz linear trapezoid transducer. 3du of the eyes were evaluated and the normal optical long axis through a line between the cornea ...

II and III, I and II, I and aVF, aVL and aVF, and from a vectorial combination of leads I, II, and III. The group means were similar, but there were large intraindividual differences of the QRS axis (up to ±350) and, to a somewhat lesser degree, of the T axis between the different lead combinations. Hypothetically, the axes from different lead combinations should be identical. The intraindividu...