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187 Solid-state colonic manometry 8 The other motor pattern we specifically looked for was the pan-colonic pressurization. Unlike Corsetti et al. , we were unable to identify these motor patterns in our patient population. However, it should be noted that in the study by Corsetti et al. , the motor pattern was primarily identified in the healthy adult colon, and was significantly diminished in constipated adults. 15 As no previous studies have described pan-colonic pressurizations in children before, we conclude that this motor patterns is also absent in constipated children. There are some limitations that need to be taken into account when interpreting these results. Ideally we would have performed repeat studies in the same children with the two different catheter types. However, these are invasive procedures and asking children to come back for a repeat study would pose ethical concerns. To compensate for this, we assessed manometry recordings performed in patients with the same constipation symptoms. We also made the assumption that a “normal”meal response in children would be the same as that recorded in healthy adults. As has been argued before, normal colonic data in children is just not available and therefore comparisons against adult data is always going to be needed. 11,13,31 However, it is important to note that regardless of the placement technique the meal response was absent. Finally, unlike the recent studies in adults and children, we did not attempt to characterize the direction of propagation of cyclic activity. 13,14 The catheter in this study had a sensor spacing of 3 cm and we have previously shown that a sensor spacing distance of >2 cm may lead to misinterpretation of frequency, morphology, and directionality of colonic propagating sequences. 21 Therefore in this study we only performed analysis on the change in cyclic activity before and after a meal, without considering the direction of propagation. CONCLUSIONS AND INFERENCES These data indicate that in children with FC, coordinated propagating motor patterns (long single motor patterns, HAPCs or both) can still be recorded, indicating a preservation of neural pathways within the enteric nervous system. However, similar to previously published results utilizing a water-perfused catheter 13 , we also observed an impaired colonic meal response in children with intractable FC. As these data in our current study were recorded with a solid-state catheter placed by various different techniques it indicates that the diminished or absent meal response is not due to protocol variations.