RESUMEN
Abstract. Background: Colonic diverticulum is one of the rare findings in dogs characterized by an out-pouching of mucosal and submucosal layers through the defect in muscularis layer of the colon. Case description: A five years old intact female Labrador was presented with an anamnesis of dyschezia and tenesmus. Findings/treatment and outcome: Rectal examination was normal, and the survey radiograph showed an almost crescent shaped abnormal dilatation (10.52 cm × 6.21 cm) with gas and increased radiopaque material, dorsal to the urinary bladder and ventral to the descending colon suggesting fecal stasis. Ultrasonographic examination revealed gas-filled out-pouching with hyperechoic colon wall and acoustic shadowing. Exploratory celiotomy confirmed the diagnosis of colonic diverticulum, and diverticulectomy was performed. All four layers of the colonic wall were detected histopathologically in the biopsy sample and excluded neoplasia. The dog recovered uneventfully with no post-operative complications. Conclusion: This surgery produced an excellent resolution of clinical signs. To our knowledge, this is one of the few cases of colonic diverticulum reported in dogs.
RESUMEN
Global and local attenuation coefficient estimations were performed in a phantom using a pulse echo method based on the rate of decay of zero crossing density. Focussed and unfocussed 3.5 MHz transducers were used. It was found that good global estimates could be made with either transducer over a 2:1 range of attenuation coefficient. Local estimates exhibit large bias errors and a high degree of variability. This variability diminishes in the focal zone of the focussed transducer and in the far field of the unfocussed transducer.