Bart M. Wiarda MD, Abstract Co-Author: Nothing to Disclose

Elsbeth Langendijk, Abstract Co-Author: Nothing to Disclose

Annebeth Vries de, Abstract Co-Author: Nothing to Disclose

Kees Jan Ponsen, Abstract Co-Author: Nothing to Disclose

Jaap Stoker MD, PhD, Abstract Co-Author: Research Consultant, Robarts Clinical Trials

Maile Stam MD, Presenter: Nothing to Disclose

To analyse the impact increased use of imaging including the introduction of MRI on outcome in children suspected for acute appendicitis who have an inconclusive or negative ultrasound (US).

Retrospective study with comparison of two cohorts of children (3-18 years) who were suspected of acute appendicitis: 2005/2006 (prior to introduction of MRI in inconclusive or negative ultrasound cases) and 2010/2011 (after introduction of MRI). The imaging findings, diagnosis, perforation rate, rate of negative diagnostic laparoscopies and length of stay were compared. Reference standard: operation/ pathological diagnose and follow-up.

In total 276 patients were included in 2005/2006(♀ 124, mean age 11.6 year SD 3.7) and 265 in 2010/2011(♀ 113, mean age 12.0 year SD 3.6). The groups were comparable for number of cases, age, sex and prevalence of appendicitis (184 (66.7%) versus 189 (71.3%) P=0.211) and number of operations (n=208 versus n=200, P=0.976). In period 2010/2011 260 patients underwent US versus 210 in 2005/2006 with a significant increase (P < 0.0001) in the last period. There was no significant difference between the number of inconclusive/negative US (n=98 versus n=117, P=0.718). The number of MRI after an inconclusive/negative US in 2010/2011 was 64 versus 1 in 2005/2006. In the period 2005/2006 there were significantly more perforations (n=56 versus n=34;P=0.0217,) more negative diagnostic laparoscopies (9 (4.5%) versus 1 (0.5%);P=0.0302), and a longer hospital stay (4,0 SD 4,6 versus 2,7 SD 2,3; P=0.001). Sensitivity and specificity of US in 2005/2006 was 79% (95%CI: 70.2-85.2) and 60% (95%CI: 27.4- 86.3), respectively and 2010/2011 74% (95%CI: 67-80.1) and 67% (95%CI: 30.9-90.9), respectively. For the MRI sensitivity and specificity in 2010/2011 were 95% (95%CI: 80.9-99) and 88% (95%CI: 67.7-96.8), respectively.

The increased use of imaging including the introduction of MRI in inconclusive or negative US cases coincides with a decrease in negative diagnostic laparoscopies, perforations and a shorter hospital stay.

Increasing use of ultrasound and MRI in children suspected of acute appendicitis improves outcome and reduces length of stay. Introduction of the strategy may reduce complications and healthcare costs

Wiarda, B, Langendijk, E, Vries de, A, Ponsen, K, Stoker, J, Stam, M, The Impact of Increased Use of Imaging Including MRI on Outcome of Children Suspected for Acute Appendicitis Who Have an Inconclusive or Negative Ultrasound.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12029029.html