Low‐field magnetic resonance imaging findings in polo ponies

Background: Currently, there is limited information regarding the locations and number of strangulating lipoma obstructions (SLO) and incidental lipomata.Objectives: To identify the most common sites of lipoma formation in the mesentery and omentum.Study design: Prospective, multicentre, case-control study.Methods: Data were collected from 385 horses undergoing exploratory laparotomy or post-mortem examination for evaluation of acute colic at eight participating centres in the UK and USA over 27 months.Lipoma presence, location, size, number and physical features (nonstrangulating, strangulating, pedunculated, non-pedunculated) were recorded.Descriptive data were generated and t tests performed where appropriate.p < 0.05 was considered significant.Results: Lipomata were found in 49.4% (n = 190) of horses.The most frequent location was the middle third of the jejunum, accounting for 22.8% (n = 84/368) of incidental lipoma and 32.4% (n = 35/108) of SLO.SLO in this location required intestinal resection in 91.4% (32) of cases.The next most common site for incidental lipomata and SLO was the distal third of the jejunum; this was followed by the ileum.The small colon exhibited 13.6% (50/368) incidental lipomata and 13.9% (15/108) SLO; resection and anastomosis was required in 53.3% (8) of SLO in the small colon.The omentum accounted for 10.6% (39/368) of incidental lipomata and 9.3% (10/108) of SLO, 60% of which required resection and anastomosis.No lipomata were detected in the rectum and there were no SLO in the duodenum or large colon/caecum.SLO had a significantly larger volume ( p = 0.001; 95% CI: 5.3-217.3)and longer pedicle length ( p < 0.001; 95% CI: 1.21-6.2) than incidental lipomata.