Radiographic and Ultrasonographic Evaluation of Egg in Healthy and Egg-Bound Green Iguana

Document Type : Diagnostic Imaging Techniques


1 Department of Surgury and radiology, Faculty of Veterinary Medicine, University of Tehran

2 Department of Small Animals Internal Medicine, Faculty of Veterinary Medicine, University of Tehran

3 Graduated From the Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran


BACKGROUND: Reproductive diseases are among the most important life threatening problems in captive female iguanas. Egg binding is a reproductive disorder in which female iguana cannot lay one or more of its eggs, mainly caused by improper husbandry. Physiological and pathological process of egg production such as egg binding in iguanas has to be assessed more.
Objectives: In this study, diagnostic value of two modalities, radiography and ultrasonography, have been compared for evaluation of egg binding in green iguana.
Methods: In this study ultrasonography and digital radiography were used as non-invasive methods to evaluate and describe dystocia in captive female green iguanas. Ultrasonography was performed in ventral aspect of abdomen in two sagittal and transverse planes. While radiographic images were taken in both dorso-ventral (DV) and lateral projections.
Results: Ultrasonography provided more accurate and informative results than digital radiology. Radiography can be used to detect gravidity and presence of large eggs or follicles. Heterogeneous echogenic eggs or follicles, with different egg size, irregularity in egg borders and echogenic free fluid in celomic cavity were detected in egg-bound green iguanas. Among these ultrasongraphic evidences, the strongest sign was presence of echogenic free fluid in celomic cavity. However digital radiography is unable to delineate fluids in celomic cavity following egg binding in green female iguanas. Among two radiographic positioning, dorso-ventral view provides more information than lateral images.
Conclusions: In conclusion, when we encounter a female green iguana with clinical signs of egg binding, ultrasonography has more advantages than radiography, however both modalities can be informative


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