Modified Lateral and Lateral Oblique If evaluation of the entire length of the urinary tract is of concern in a male, the hind limbs may mask the membra- nous and penile urethra' in a true lateral position. There are two alternatives that could be considered the modified lateral and lateral oblique. Modified Lateral Positioning Place In: Right lateral recumbency. Head: Keep in a natural position, and hold appropriately with a sandbag over the neck. Be careful not to restrict breathing. Forelimbs: Pull cranially and sandbag. Place a small foam pad between the forelimbs to help eliminate rotation of the cranial abdomen. Hind Limbs: Pull the pelvic limbs cranially as far forward as possible without causing rotation of the body from the table. An appropriately sized foam pad placed between the femurs may help eliminate rotation of the pelvis. Place sandbags over the limbs. BOTH POSITIONS Measure: Over the ischium. Central Ray: Over the cranial wing of the ilium unless the rectum is of interest; in that case have the central beam over the pelvis. Borders: For a bladder, prostate, or caudal contrast study, include L4 and the caudal aspect of the rectum. TECHNICIAN NOTES Remember to collimate to the area of interest and include the markers. FIGURE 18-8 Positioning for a modified lateral view of a male for contrast studies. The hind limbs are pulled cranially as far as possible for evaluation of the membranous and penile urethra. Sternum: Elevate the ventral abdomen with wedged sponges so the sternum is at the same plane as the vertebrae. Have the central ray be perpendicular to both. Comments and Tips Ensure that the pelvic limbs are not superimposed over the caudal aspect of the os penis. . Expose immediately at the end phase of expiration. Lateral Oblique Positioning Place in: Right lateral recumbency. Head: Keep in a natural position and support appropriately with a sandbag over the neck. Forelimbs: Pull cranially and sandbag. Hind Limbs: Pull the dependent limb caudally and place a sandbag over the femur to keep in position. Raise the contralateral limb so that it is pulled dorsally and out of the field of view. A bungee cord or gauze tied around the tarsus and metatarsus and secured to the table, machine or sandbag will help keep the limb out of the field of view. B LO-20' FIGURE 18-9 A, Positioning for lateral oblique view of the canine abdomen. Ensure that the pelvic limbs are not superimposed over the caudal aspect of the os penis. B, Lateral oblique radiograph of the abdomen of a feline patient during an excretory urography using iodine.