Diagnosis and Management of Marine Debris Ingestion and Entanglement by Using Advanced Imaging and Endoscopy in Sea Turtles
Marine debris ingestion and entanglement have caused morbidity and mortality in multiple marine species, including all seven species of sea turtles. This case series outlines six cases in which advanced imaging modalities were used to diagnose marine debris–induced foreign body obstructions and to aid in the treatment of wounds caused by marine debris entanglement. Prefemoral ultrasonography was used to correctly diagnose a monofilament fishing line linear foreign body obstruction in a juvenile female Kemp's Ridley sea turtle (Lepidochelys kempii) and a subadult female loggerhead sea turtle (Caretta caretta). Administration of iodinated contrast confirmed a complete upper gastrointestinal obstruction in a juvenile green sea turtle (Chelonia mydas). Traditional radiographs were nondiagnostic in all three animals. Barium-impregnated polyethylene spheres were used to identify a partial gastrointestinal foreign body obstruction in a juvenile green sea turtle. Endoscopy was used in multiple cases as both a diagnostic and a therapeutic tool. This case series demonstrates that contrast radiography, ultrasonography, and endoscopy are accurate diagnostic tools for the identification of marine debris–induced foreign body obstructions in sea turtles.Abstract
Ultrasonographic image of case 1 obtained via the left prefemoral acoustic window. The white arrow indicates a region of plicated small intestines consistent with a linear foreign body obstruction. There is a hypoechoic region present superficial to (above) the plicated intestines containing a hyperechoic linear structure, consistent with free coelomic fluid and fibrin strands or inflamed mesentery, respectively. This image is from the same clinical case presented in figure 13.19(b) in “Sea Turtle Health and Rehabilitation” (Manire et al., 2017; published with permission).
Intraoperative image from case 1 demonstrating a small intestinal intussusception secondary to a monofilament fishing line linear foreign body.
Serial dorsoventral radiographs from case 4 demonstrating the movement of BIPS through the GI tract, and the presence of barium contrast material in the colon and distal small intestines. Image (a) shows the BIPS (arrow) in the right cranial, lateral coelom on day 14. Image (b) shows the BIPS (circle) in the caudal-central coelom in the region of the small intestines on day 22. Image (c) shows the BIPS in the large intestines (arrow) as well as barium contrast filling the lumen of the large intestines to the distal small intestines (circle) on day 28. Image (d) shows complete clearance of the BIPS and barium on day 54 of rehabilitation.
Dorsoventral radiographs of case 5 obtained 7 days after presentation. Image (a) was obtained before contrast administration; the metal opaque object that was suspected to be part of a fishing hook is circled in white, and the severe interstitial pattern in the lungs and the left femoral fracture can also be seen. Image (b) was obtained after administration of 60 ml of iodinated contrast material into the colon via the cloaca; the contrast extended into the distal large intestines and obstructed visualization of the metallic object (arrows).
Radiograph images from case 6. Image (a) was taken on admission; no abnormalities were noted in the gastrointestinal tract. Image (b) was obtained 6 days after presentation; gas distension within the GI tract was noted in the left cranial and right middle coelom (arrows). Image (c) was taken 14 days after presentation and after contrast administration; iodinated contrast is visible in the colon (arrows) and outlining the stomach (circle). Image (d) was taken 17 days after presentation and 3 days after contrast administration; the majority of the contrast exited the colon, with a small amount remaining (arrow). All of the contrast remained in the stomach with no apparent filling of the duodenum (circle).
Necropsy images from case 6. Image (a) depicts the significant expanse of intestinal plication. Image (b) is the intussusception located in the distal small intestines. Image (c) shows the small intestinal perforation that was found in an area of plication (circle).
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