Sonographic appearance of the normal appendix in children.

ABSTRACT

PURPOSE: To determine the visualization rate of the appendix in children without appendicitis and investigate factors affecting it. METHODS: Between January 2010 and April 2010, 205 consecutive children (103 boys and 102 girls; mean age 9 years) without clinical signs of appendicitis were examined by ultrasound (US). The location of appendix was determined. The outer appendiceal diameter with and without compression was measured and the content of the lumen and mural vascularity on color Doppler was determined. The appendix diameter was correlated with age, weight, and height using Pearson correlation. For age, weight, and height, children with a visualized appendix were compared with those in whom the appendix was not visualized using Student's t test. RESULTS: The appendix was visualized in 142 of 205 (69.3%) children. The mean diameters of the appendices without and with compression were 4.2 ± 0.9 mm and 3.5 ± 0.8 mm, respectively, with 53.5% of the appendices in the mid-pelvic location. Appendiceal lumen was empty in 35.2% of children. Only one appendix showed mural vascularity on color Doppler. There was no correlation between the diameter (compressed or noncompressed) of the appendix and age, weight, or height. Mean ± SD age, weight, and height of the children with a visualized appendix (8.6 ± 0.3 years, 29.9 ± 0.9 kg, 127.7 ± 1.7 cm, respectively) were significantly lower than those in children with a nonvisualized appendix (9.8 ± 0.4 years, 36.0 ± 1.8 kg, 134.7 ± 2.5 cm, respectively) (p < 0.05 for all three parameters). CONCLUSION: In the majority of the children, the appendix can be visualized with US. Age, weight, and height affect the visualization rate of the normal appendix.