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185 Solid-state colonic manometry 8 Pan-colonic pressurizations At no stage were we able to identify synchronous pressure events spanning all recording sites. All events in which a sequence of pressure waves spanned all recording sites had a time lag between the start of the pressure wave in the first sensor and the start of the pressure wave at the last sensor. A re-analysis of the water pressure data from the previous study also failed to identify pan-colonic pressurizations. Spectral analysis Figure 1 shows the results of the spectral analysis. Similar to what was previously shown in children with FC measured with water-perfusion manometry 13 , children with FC in the current study exhibited a lack of the 2–4 cycle per minute activity which dominates colonic motility recordings in healthy adults (Figure 1). 13,16 Moreover, there was no increase in colonic pressure events after the meal, unlike previous observations in healthy adults. 16 This finding is similar to what was seen in previous studies in constipated children and adults measured with water-perfused and fiber-optic manometry. 13,14 DISCUSSION These data, recorded by a solid-state manometry catheter, show that in children with intractable FC the postprandial colonic meal response is impaired. Although propagating contractile activity was observed in all children, they lack the normal increase in postprandial motor activity at 2-4 cycles per minute which has been described in healthy adults. 16 These data support the findings from previous studies in adults and children with FC, performed with different types of manometry catheters, 13,14 which also noted a failed meal response. This suggests that the findings in our previous study of colonic motor abnormalities in children with FC were not the result of the recording technique. 13 In healthy adults, cyclic motor activity in the distal colon increases within one minute of starting a meal. 14 This gastro-colonic response is likely to be mediated by extrinsic neural input. 14,17 Similar to the current study, a lack of postprandial increase in cyclic motor activity has been observed in adults with slow transit constipation and children with intractable FC. 13,14 This impaired postprandial response suggests that an extrinsic neuropathy may exist in these patients. Although an intrinsic defect cannot be ruled out entirely, the presence of coordinated propagating contractions, such as long single motor patterns or spontaneous or chemically induced HAPCs suggests that the intrinsic neural network is at least partially functional and capable of generating coordinated propagating pressure events.