Introduction
Pelvic floor dysfunction is highly prevalent. Posterior compartment disorders include fecal incontinence (FI) and obstructive defecation syndrome (ODS). Assessment of the sphincter complex's (SC) ability to resist or yield to distension may provide a valuable method for evaluating continence and defecatory function.
Aims & Methods
Women with FI, chronic constipation (CC) and suspected functional defecation disorder (FDD), as well as healthy volunteers (HV) were included. Impedance Planimetry (IP) was performed using the anal functional lumen imaging probe [EndoFLIPTM System (Medtronic®) with an 8-cm catheter (EF-325N)]. A “stepwise” measurement protocol was applied, with bag filling from 0 to 50ml in 10-ml increments. Distensibility index (DI) was recorded at rest, voluntary squeeze, cough maneuver and during simulated evacuation at 30-, 40- and 50-ml volumes. Simulated defecation was evaluated by calculating the percentage change in the DI relative to resting values at each volume.
Results
Fifteen women were included: 4 HV (26.7%), 7 with FI (46.7%) and 4 with CC (26.7%). Women with FI were older than those in the CC and HV groups (median age: FI 72 years [66–75], CC 55 years [42-63], HV 48 years [ 43–53], p = 0.009. Median BMI was similar among groups [HV 24.0 Kg/m2 (21.6 – 25.3), FI 27.0 Kg/m2 (24.3 – 30.0) and CC 26.2 Kg/m2 (21.5 – 30.5), p=0.367]. The DI was significantly higher in the FI group compared to CC and HV groups at rest, during squeeze and during cough maneuver across 30-, 40- and 50-ml volumes. The percentage change in DI during simulated defecation at 50 ml was significantly reduced in CC compared to HV (p=0.030). When groups were categorized based on suspected FDD (CC vs HV+FI), the percentage change in DI was significantly lower in CC at 40 ml [74% (37 – 109) vs 175% (100 – 250), p=0.037] and at 50 ml [81% (43 – 96) vs 111% (96 – 119), p=0.048].
| Anal EndoFLIPTM |
N (%)
15 (100) | Healthy Volunteers
4 (26.7) | Fecal Incontinence
7 (46.7) | Chronic Constipation
4 (26.7) | P value |
30 ml DI (mm2*mmHg-1). Median (IQR)
- At rest
- During squeeze
- Cough maneuver
- Simulated defecation
30 ml Percentage change in DI (%). Median (IQR) |
0.5 (0.4 – 0.7) §
0.3 (0.2 – 0.3) §
0.4 (0.3 – 0.5) §
0.9 (0.6 – 1.1) §
158 (106 – 205) |
1.3 (0.9 – 3.0) †§
1.1 (0.9 – 1.3) †§
2.4 (1.0 – 3.0) †§
3.2 (1.4 – 4.9) †§
156 (99 – 356) |
0.5 (0.4 – 0.5) †
0.3 (0.2 – 0.4) †
0.4 (0.3 – 0.4) †
0.3 (0.2 – 0.4) †
77 (48 – 100) |
0.010
0.005
0.009
0.016
0.266 |
40 ml DI (mm2*mmHg-1). Median (IQR)
- At rest
- During squeeze
- Cough maneuver
- Simulated defecation
40 ml Percentage change in DI (%). Median (IQR) |
1.0 (0.6 – 1.3)
0.2 (0.2 – 0.4) §
0.6 (0.4 – 0.8) §
1.4 (1.3 – 1.9) §
178 (138 – 216) |
3.5 (3.0 – 6.9)
2.7 (2.4 – 3.0) †§
2.9 (2.3 – 5.3) †§
5.9 (3.9 – 9.2) †§
141 (73 – 295) |
1.3 (1.1 – 1.5)
0.8 (0.5 – 1.3) †
1.2 (0.7 – 1.4) †
1.1 (0.5 – 1.5) †
74 (37 – 109) |
0.030
0.004
0.003
0.005
0.108 |
50 ml DI (mm2*mmHg-1). Median (IQR)
- At rest
- During squeeze
- Cough maneuver
- Simulated defecation
50 ml Percentage change in DI (%). Median (IQR) |
2.2 (1.2 – 2.9) §
0.5 (0.2 – 1.0) §
1.4 (0.7 – 2.3) §
3.0 (2.4 – 3.4) §
117 (113 – 301) ¶ |
5.4 (4.6 – 6.9) §
4.5 (3.8 – 5.0) §
5.0 (4.6 – 5.8) §
5.5 (4.6 – 6.0) †§
99 (95 – 110) |
3.2 (2.8 – 4.5)
1.7 (1.0 – 3.5)
2.9 (1.7 – 4.1)
2.6 (1.2 – 4.3) †
81 (43 – 96) ¶ |
0.002
0.002
0.005
0.016
0.030 |
†=Statistically significant difference (p<0.05) between FI and CC groups. §= Statistically significant difference (p<0.05) between FI and HV groups. ¶= Statistically significant difference (p<0.05) between CC and HV groups.
Conclusion
Impedance planimetry proves to be a valuable tool for distinguishing pelvic floor dysfunctions, as women with FI show higher DI values, whereas those with suspected FDD exhibit reduced DI changes during simulated defecation. These findings support the hypothesis that impaired rectal distensibility is a key feature of FDD, highlighting its role in continence and evacuation disorders.
References
-Leroi AM, Melchior C, Charpentier C, et al. The diagnostic value of the functional lumen imaging probe versus high-resolution anorectal manometry in patients with fecal incontinence. Neurogastroenterol Motil. 2018;30(6):e13291. doi:10.1111/nmo.13291
-O'Connor A, Byrne CM, Vasant DH, et al. Current and future perspectives on the utility of provocative tests of anal sphincter function: A state-of-the-art summary. Neurogastroenterol Motil. 2023;35(7):e14496. doi:10.1111/nmo.14496
