BENEFITS OF A COMPLETE X-RAY EVALUATION OF POSITION AND ORIENTATION OF FISHING HOOKS IN INTRACOELOMATIC ESOPHAGUS FOR THE CHOISE OF APPROPRIATE SURGICAL APPROACH IN LOGGERHEAD SEA TURTLES (CARETTA CARETTA)

Radiographic studies are among the most important diagnostic procedures in the clinical evaluation of sea turtles. The anatomical structures for which it is possible to obtain an optimal assessment by radiographic examination are respiratory tact, digestive tract, skeleton, carapace, and plastron. The fundamental and indispensable projections for a proper radiographic estimation of the body are dorsoventral view, vertical beam, horizontal beam, lateral view, and craniocaudal view. Radiographs in the dorsal-ventral projection usually allow achieving the detection of fishhooks in the various sections of the digestive tract. In fact, hooks are poorly detectable in other projections due to the intense radiopacity determined by the superimposition of other anatomical structures, and to the inability to set the radiographic cassette in strict contact with the body of the animal. On the contrary, when the hooks are stacked in the esophagus wall, especially in the intracoelomatic tract, images in the dorsoventral beam do not allow to ascertain if the tip or the hook barbs are dangerously close to airways (trachea and bronchi) or great vessels (brachycephalic trunk). Without this information, the surgeon risks to cause irreparable injuries during the removal of the hook. On the other hand, a complete radiographic study in two orthogonal projections is invaluable to correctly assess position and orientation of the hook to properly schedule the surgery. The present study included 21 loggerhead sea turtles (Caretta caretta) referred to the Department of Veterinary Medicine of Bari University (Italy), which showed drifting longlines hooks located in the caudal cervical or intracoelomatic esophagus subsequently to a first radiographic evaluation in dorsoventral beam. The other radiographic projections were obtained in horizontal beam lateral view, with turtles set on a radiolucent support (plastic box) with the surface of the radiographic cassette adherent to the lateral margin of the bridge. In order to reduce the overlap of soft tissues of the pectoral girdle, the front flippers were forward stretched below the neck, and temporarily wrapped together with self-adhesive elastic bandage. X-ray images were obtained with a digital acquisition system, which allowed improving contrast and brightness of images by graphic processing. The opportunity to evaluate different radiograms obtained in two orthogonal projections has allowed to precisely locate the position of hook, shank and bend with respect to the horizontal midsagittal plane the animal, the orientation of the tip (cranially, caudally or laterally), and above all the closeness to vital anatomical structures. These significant assessments have allowed choosing the most appropriate surgical approaches, and to avoid dangerous intraoperative maneuvers during removal of hooks.