MR Defecography Findings Suggesting Anismus: Reliable or not Reliable?

Abstract

Objectives: We aimed to describe the MR defecography findings of anismus, and to compare them with those seen in other pelvic floor disorders. Materials and Methods: MR defecography findings suggesting anismus (Group 1) were compared with findings of other pelvic floor abnormalities (Group 2). Anorectal angle (ARA) was measured both at rest and during defecation. Anal canal diameter was measured as the width of ultrasound gel column passing through the anal canal during defecation on CINE images. Percentage of rectal emptying was calculated by measuring the maximum dimension of contrast-filled rectum at rest and of retained contrast material at the end of the examination after defecatory attempts. MR images were retrospectively evaluated by two radiologists in consensus. Results: There were 60 patients in Group 1 (39 female, mean age 45 years), and 41 patients in Group 2 (39 female, mean age 54 years). The mean ARA at rest was 97.7° in Group 1, 106.8° in Group 2, and ARA during defecation was 98.8° in Group 1, and 134.9° in Group 2. The mean value of rectal emptying was 35%, and 83% in Group 1 and 2, respectively. Anal canal did not open in 5 patients, the width of the anal canal was less than 10 mm in 48 patients, and was between 10 and 14 mm in 7 patients in Group 1. It was less than 10 mm in 9 patients, between 10 and 15° in 12 patients and more than 15 mm in 20 patients in Group 2. There was a statistically significant difference between two groups in all parameters (p<0.05). Accompanying pelvic floor pathologies were present in 28 patients in Group 1 (47%), and rectocele was the most frequent associated abnormality. Conclusion: MR defecography findings in patients with anismus are significantly different from other pelvic floor pathologies.

Keywords

• Anismus
• MR Defecography
• Dyssynergic Defecation

Anismus’a İşaret Eden MR Defekografi Bulguları: Güvenilir mi, Değil mi?

Abstract

Amaç: Amacımız anismusun MR defekografi bulgularını tanımlamak ve bunları diğer pelvik taban hastalıklarına ait bulgularla karşılaştırmaktır. Gereç ve Yöntem: Anismusa işaret eden MR defekografi bulguları olan hastalar (Grup 1) diğer pelvik taban hastalıklarına ait bulguları olan hastalar (Grup 2) ile karşılaştırıldı. Anorektal açı (ARA) istirahatte ve defekasyon sırasında ölçüldü. Defekasyon sırasında ultrason jeli anal kanaldan geçerken anal kanal genişliği ölçüldü. İstirahat sırasında kontrast madde ile dolu olan rektumun maksimum genişliği ve inceleme sonunda kalan kontrast maddenin çapı ölçülerek rektal boşalma derecesi hesaplandı. MR görüntüleri 2 radyolog tarafından retrospektif olarak ve fikir birliği ile değerlendirildi. Bulgular: Grup 1’de 60 hasta (39 kadın, ortalama yaş 45), Grup 2’de 41 hasta (39 kadın, ortalama yaş 54) mevcuttu. İstirahatte ortalama ARA Grup 1’de 97,7°, Grup 2’de 106,8°, defekasyon sırasında ARA Grup 1’de 98,8°, Grup 2’de 134,9° ölçüldü. Ortalama rektal boşalma derecesi Grup 1’de %35 ve Grup 2’de %83 idi. Grup 1’de 5 hastada anal kanal açılmaz iken 48 hastada anal kanal çapı <10 mm, 7 hastada 10-14 mm olarak ölçüldü. Anal kanal çapı Grup 2’de 9 hastada <10 mm, 12 hastada 10-15°, 20 hastada >15 mm olarak ölçüldü. Bütün parametreler 2 grup arasında istatistiksel olarak anlamlı fark göstermekteydi (p<0,05). Sonuç: Anismuslu hastalarda MR defekografi bulguları diğer pelvik taban hastalıklarına göre anlamlı olarak farklılık göstermektedir.

Keywords

• Anismus
• MR Defekografi
• Dissinerjik Defekasyon

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