Table 1.

 Rectal balloon distension thresholds and pain/discomfort during tonic rectal distension in 10 controls and 10 irritable bowel syndrome

	1st sensation (ml)	Defecation urge (ml)	Pain detection (ml)	Pain tolerance (ml)	Tonic distension during fMRI (ml)	Distension: pain (VAS 0–100)	Distension: discomfort (VAS 0–100)
Controls	41 (24–58)	118 (93–143)	195 (142–248)	270 (204–335)	227 (170–284)	52 (36–68)	48 (32–64)
IBS-all	53 (24–81)	157 (118–195)	271 (194–347)	363 (263–463)	320 (226–414)	47 (38–56)	43 (28–57)
IBS-C	63 (14–100)	183 (101–265)	322 (153–491)*	443 (239–647)*	386 (183–590)†	47 (30–65)	47 (20–74)
IBS-D	42 (21–63)	130 (103–157)	219 (184–254)	283 (235–331)	253 (211–295)	47 (31–63)	38 (15–61)

Means (95% confidence intervals) are shown.

IBS-C, five patients with IBS with constipation; IBS-D, five patients with IBS with diarrhoea; VAS, visual analogue scale (0 = none, 100 = unbearable); fMRI, functional magnetic resonance imaging.

*p<0.05, IBS-C versus healthy controls and IBS-D; †p = 0.03, IBS-C versus healthy controls.