ranging in weight from 266 to 320 q and a dosage of 75 mg (0.25 

 cc of sodium diatrizoate 50%) in the two turtles weighing 

 approximately 100 g were given (less than 85% of maximum animal 

 dose) (Gillette, 1977). The contrast material was administered 

 with disposable plastic syringes, using 26-gauge needles. All 

 radiographic exposures were made on standard radiologic equipment 

 available in the Department of Radiology, University of Texas 

 Medical Branch, Galveston, Texas, using standard radiographic 

 techniques, regular radiographic cassettes (Kodak X-omatic™ 

 regular cassette, Eastman Kodak Co., Rochester, N.Y.) equipped 

 with high-speed intensifying screens (Kodak X-omatic*™ regular 

 intensifying screens, Eastman Kodak Co., Rochester, N.Y.) and 

 standard medical radiographic film (Dupont Cronex^ Four safety 

 film, E. I. Dupont de Nemours and Co, Photo Products Dept., 

 Wilmington, De.). (Table 1). 



On each day of the study, two healthy ridley turtles were 

 selected and were iniected subcutaneously (with sodium 

 diatrizoate) , one in the ventral surface of a hind limb and the 

 other in the dorsal aspect of the neck after sterile preparation 

 of the overlying skin with an iodophor solution. Satisfactory 

 injection was determined by two criteria: little or no leak of 

 contrast through the needle track after the needle was withdrawn, 

 and after the 5-min film, the retention by the opacified area of 

 a nearly round or ovoid shape with little dissection along 

 fascial planes, thus allowing for a similar volume and surface 

 area for absorption. If the criteria were met, filming was con- 

 tinued for 15, 30, and 60 min after iniection. The films on each 

 animal were made in the dor sol-ventral projection with the 

 radiographic technique detailed in Table 1. Upon completion, all 

 studies were reviewed by five radiologists and were graded on the 



