Abstract

Normal radiographic interpretation is the first step in distinguishing and interpreting abnormal pulmonary radiographic findings in ill sea turtles. The goal of this study was to 1) provide normal radiographs with interpretation for juvenile Kemp’s ridley (Lepidochelys kempii) sea turtles, 2) assess the best radiographic views for ideal lung interpretation of normal anatomy in this species, and 3) describe normal variations that may be found on images that may influence interpretation. Fifty-three individuals incidentally caught on hook and line Kemp’s ridleys were selected for this study after evaluation of their medical records, including physical examination, complete blood counts, plasma chemistries, and radiographs, interpreted by two board-certified radiologists determined that they were likely normal. Fifty-five digital radiographs were retrospectively used to determine the normal radiographic anatomy of the lower respiratory tract from 2016 to 2020. Radiographic views included dorsoventral, rostrocaudal, and right and left lateral projections. The most conducive views for assessing global lung volume and symmetry were the dorsoventral (DV) and rostrocaudal view (RoCD). The DV and lateral views were best for the main bronchus, branching channels, and lung margination. The RoCD view was most useful for assessing the symmetry of lung opacity. The lateral views were most helpful for assessing the ventral margin of each lung lobe. On the lateral view the main bronchus laid ventrally and coursed horizontally through the lung from cranial to caudal. On the DV view the bronchus laid medially and was observed to be curvilinear, coursing caudomedially. On the RoCd view the main bronchus was located ventromedially. The RoCd view demonstrated the channels and niches end-on resulting in a reticulated or honeycomb appearance. The channels were seen as uniform striations coursing perpendicular to the main bronchus on the lateral views (vertical striations coursing dorsal to ventral) and DV views (horizontal striations coursing medial to lateral).