Journal of Research in Medical Sciences1735-1995231201802031074710747EN20180131<span class="fontstyle0">Background: </span><span class="fontstyle2">Normal size of mesenteric lymph nodes has not been well evaluated, as these lymph nodes are small but may be seen frequently in computed tomography (CT). Te aim of this study is to determine the prevalence of mesenteric lymph nodes at root of mesentery and mesentery itself. </span><span class="fontstyle0">Materials and Methods: </span><span class="fontstyle2">Tis is a cross?sectional study on traumatic patients with normal multidetector CT (MDCT) referred to Al?Zahra Hospital in 2014–2016. Te largest short axis of lymph nodes was recorded. Teir location was divided into three groups of mesenteric root, peripheral mesentery, and mesentery of the right lower quadrant (RLQ).<br />Size and number of lymph nodes in terms of locations were recorded. A number of more than 6 nodes in a position was defned as cluster nodes. Data were analyzed using SPSS software version 20. </span><span class="fontstyle3">P </span><span class="fontstyle2">&lt; 0.05 was considered statistically signifcant. </span><span class="fontstyle0">Results: </span><span class="fontstyle2">Four hundred traumatic patients underwent MDCT scanning. Te mean age of these patients was 36.6 ± 13.4 years. Te number of lymph nodes was &lt;3 in 49.3%, 52.5%, and 52.2%; 3–6 in 45.8%, 42.8%, and 42.8%; &gt;6 in 5%, 4.8%, and 4.8% of central, peripheral, and RLQ mesentery, respectively. Te average size of largest central, peripheral, and RLQ lymph nodes was 4.53 ± 1.33, 4.37 ± 1.68,<br />and 4.37 ± 1.68, respectively (</span><span class="fontstyle3">P </span><span class="fontstyle2">= 0.64). Largest size of short axis in  patients with cluster lymph nodes was signifcantly more than noncluster nodes (</span><span class="fontstyle3">P </span><span class="fontstyle2">&lt; 0.001 for all regions). </span><span class="fontstyle0">Conclusion: </span><span class="fontstyle2">Mean size of mesenteric lymph nodes was similar to the previous study, but the largest nodes were considerably larger. Furthermore, largest short axis of cluster nodes was signifcantly more than noncluster ones.</span><span class="fontstyle0"> </span> <br style="font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px;" />http://jrms.mui.ac.ir/index.php/jrms/article/view/10747http://jrms.mui.ac.ir/index.php/jrms/article/download/10747/5586