Evaluation of normal findings using a detailed and focused technique for transcutaneous abdominal ultrasonography in the horse.

This research article presents a study evaluating the efficacy and reliability of two abdominal ultrasonography techniques – a detailed method and a focused, limited preparation approach – for identifying organ structures in horses. The structures’ locations, frequency of detection, and some normal variations were documented.

Methods and Examination Protocol

• The researchers carried out an in-depth abdominal ultrasound examination on five sound horses, repeating the procedure five times, yielding a total of 25 inspections.
• They divided the abdomen into ten distinct imaging sites to record the identified structures at each site.
• Using a single focused ultrasound examination, five imaging sites were chosen for analysis in a larger group of 20 normal horses.
• Preparation for these examinations were minimal and any ultrasound-visible features were logged as ‘identified’.
• Both the position of the organs and the frequency of their detection were recorded.

Data Analysis and Results

• The data was analysed to determine the consistency of identifying structures in each examination, regardless of the imaging site, and for each individual imaging site.
• Structures such as the caecum, colon, spleen, liver, and right kidney had defined locations and were repeatably identified utilising the detailed examination technique.
• The large colon and right kidney were found in 100% of inspections using both techniques.
• Other structures, including the liver, spleen, caecum, duodenum, and other sections of the small intestine, were identified more frequently with the detailed examination.
• Identification of small intestine occurred most often in the ventral abdomen but varied significantly within and between horses, necessitating repeated examinations in some instances.
• The left kidney was not always identifiable using either method.
• The sacculated colon was found in all ventral sites but was rarely identified in dorsal sites.

Conclusions and Clinical Implications

• The caecum, sacculated large intestine, spleen, liver, and right kidney were consistently identified with both techniques.
• However, there were some normal variations to consider when interpreting ultrasonographic findings in clinical cases. For example, the left kidney was not always identified, and the sacculated colon was occasionally found in dorsal flank sites.
• To identify the small intestine, multiple imaging sites and repeated examinations may be necessary.
• A focused examination identified most key structures, but it has certain limitations compared to a detailed examination.