Análisis de nuestra experiencia mediante el uso de resonancia magnética dinámica pelviana en la evaluación del síndrome de defecación obstructiva

Magnetic resonance defecography versus clinical examination and fluoroscopy: a systematic review and meta-analysis

BACKGROUND

Magnetic resonance defecography (MRD) allows for dynamic visualisation of the pelvic floor compartments when assessing for pelvic floor dysfunction. Additional benefits over traditional techniques are largely unknown. The aim of this study was to compare detection and miss rates of pelvic floor abnormalities with MRD versus clinical examination and traditional fluoroscopic techniques.

METHODS

A systematic review and meta-analysis was conducted in accordance with recommendations from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. MEDLINE, Embase and the Cochrane Central Register of Controlled Trials were accessed. Studies were included if they reported detection rates of at least one outcome of interest with MRD versus EITHER clinical examination AND/OR fluoroscopic techniques within the same cohort of patients.

RESULTS

Twenty-eight studies were included: 14 studies compared clinical examination to MRD, and 16 compared fluoroscopic techniques to MRD. Detection and miss rates with MRD were not significantly different from clinical examination findings for any outcome except enterocele, where MRD had a higher detection rate (37.16% with MRD vs 25.08%; OR 2.23, 95% CI 1.21-4.11, p = 0.010) and lower miss rates (1.20 vs 37.35%; OR 0.05, 95% CI 0.01-0.20, p = 0.0001) compared to clinical examination. However, compared to fluoroscopy, MRD had a lower detection rate for rectoceles (61.84 vs 73.68%; OR 0.48 95% CI 0.30-0.76, p = 0.002) rectoanal intussusception (37.91 vs 57.14%; OR 0.32, 95% CI 0.16-0.66, p = 0.002) and perineal descent (52.29 vs 74.51%; OR 0.36, 95% CI 0.17-0.74, p = 0.006). Miss rates of MRD were also higher compared to fluoroscopy for rectoceles (15.96 vs 0%; OR 15.74, 95% CI 5.34-46.40, p < 0.00001), intussusception (36.11 vs 3.70%; OR 10.52, 95% CI 3.25-34.03, p = 0.0001) and perineal descent (32.11 vs 0.92%; OR 12.30, 95% CI 3.38-44.76, p = 0.0001).

CONCLUSIONS

MRD has a role in the assessment of pelvic floor dysfunction. However, clinicians need to be mindful of the risk of underdiagnosis and consider the use of additional imaging.

Anismus, Physiology, Radiology: Is It Time for Some Pragmatism? A Comparative Study of Radiological and Anorectal Physiology Findings in Patients With Anismus

Purpose

Anismus is a functional disorder featuring obstructive symptoms and paradoxical contractions of the pelvic floor. This study aims to establish diagnosis agreement between physiology and radiology, associate anismus with morphological outlet obstruction, and explore the role of sphincteric pressure and rectal volumes in the radiological diagnosis of anismus.

Methods

Consecutive patients were evaluated by using magnetic resonance imaging proctography/fluoroscopic defecography and anorectal physiology. Morphological radiological features were associated with physiology tests. A categorical analysis was performed using the chi-square test, and agreement was assessed via the kappa coefficient. A Mann-Whitney test was used to assess rectal volumes and sphincterial pressure distributions between groups of patients. A P-value of <0.05 was significant.

Results

Forty-three patients (42 female patients) underwent anorectal physiology and radiology imaging. The median age was 54 years (interquartile range, 41.5–60 years). Anismus was seen radiologically and physiologically in 18 (41.8%) and 12 patients (27.9%), respectively. The agreement between modalities was 0.298 (P = 0.04). Using physiology as a reference, radiology had positive and negative predictive values of 44% and 84%, respectively. Rectoceles, cystoceles, enteroceles and pathological pelvic floor descent were not physiologically predictive of animus (P > 0.05). The sphincterial straining pressure was 71 mmHg in the anismus group versus 12 mmHg. Radiology was likely to identify anismus when the straining pressure exceeded 50% of the resting pressure (P = 0.08).

Conclusion

Radiological techniques detect pelvic morphological abnormalities, but lead to overdiagnoses of anismus. No proctographic pathological feature predicts anismus reliably. A stronger pelvic floor paradoxical contraction is associated with a greater likelihood of detection by proctography.