Abstract：
OBJECTIVE: Magnetic resonance defecography imaging techniques have been used widely to study pelvic floor function and diagnose pelvic organ prolapse (POP). The aim of this study was to investigate the diagnostic accuracy of the H-line to detect bladder descent compared with the current landmark, the pubococcygeal line (PCL).
METHODS: In this retrospective cohort study, patients who underwent MR defecography in our medical center and were diagnosed with moderate to severe cystocele by radiological measurements were recruited. One rest image and one maximum evacuation image for each subject were used for the following measurements: bladder base perpendicular distance from the genital hiatus (GH), indicative of clinically significant bladder descent, PCL as the current radiological reference line, and the H-line, or minimal levator hiatus line, indicative of pelvic floor muscle and connective tissue support. Subjects were categorized as having clinically significant cystocele if the \"bladder base\" reached within 1 cm or lower of the GH (stage II or higher cystocele). A comparison was performed to assess differences and predictive capabilities of the reference lines relative to the GH measure.
RESULTS: Seventy subjects were included, 30 with clinically significant bladder descent based on distance to GH. Women with bladder descent were older (64.0 ± 11.8 vs 51.2 ± 15.6, p < 0.001), had increased parity (3 [1-7] vs 2 [0-5], p = 0.009), and had a bladder that descended lower than the H-line at rest (1.9 ± 0.5 vs 2.2 ± 0.4, p = 0.003) and evacuation (-2.4 ± 1.6 vs -0.7 ± 1.1, p < 0.001). Multivariate regression analysis confirmed that age, length of the H-line at evacuation, the perpendicular distances between the H-line and the lowest bladder point at rest, and the PCL to the lowest bladder point at evacuation significantly correlated with bladder descent. Receiver operating characteristic analysis was used to identify a measurement threshold to diagnose clinically significant cystocele for both measurements, bladder base to the H-line: -1.2 (80.0, 72.5) area under the curve (AUC) 0.82, and bladder base PCL: -3.3 (77.8, 79.5) AUC 0.86.
CONCLUSIONS: Our data support the application of using the minimal levator hiatus plane and specifically the H-line as a reliable landmark to diagnose bladder descent using MR defecography imaging.
METHODS: In this retrospective cohort study, patients who underwent MR defecography in our medical center and were diagnosed with moderate to severe cystocele by radiological measurements were recruited. One rest image and one maximum evacuation image for each subject were used for the following measurements: bladder base perpendicular distance from the genital hiatus (GH), indicative of clinically significant bladder descent, PCL as the current radiological reference line, and the H-line, or minimal levator hiatus line, indicative of pelvic floor muscle and connective tissue support. Subjects were categorized as having clinically significant cystocele if the \"bladder base\" reached within 1 cm or lower of the GH (stage II or higher cystocele). A comparison was performed to assess differences and predictive capabilities of the reference lines relative to the GH measure.
RESULTS: Seventy subjects were included, 30 with clinically significant bladder descent based on distance to GH. Women with bladder descent were older (64.0 ± 11.8 vs 51.2 ± 15.6, p < 0.001), had increased parity (3 [1-7] vs 2 [0-5], p = 0.009), and had a bladder that descended lower than the H-line at rest (1.9 ± 0.5 vs 2.2 ± 0.4, p = 0.003) and evacuation (-2.4 ± 1.6 vs -0.7 ± 1.1, p < 0.001). Multivariate regression analysis confirmed that age, length of the H-line at evacuation, the perpendicular distances between the H-line and the lowest bladder point at rest, and the PCL to the lowest bladder point at evacuation significantly correlated with bladder descent. Receiver operating characteristic analysis was used to identify a measurement threshold to diagnose clinically significant cystocele for both measurements, bladder base to the H-line: -1.2 (80.0, 72.5) area under the curve (AUC) 0.82, and bladder base PCL: -3.3 (77.8, 79.5) AUC 0.86.
CONCLUSIONS: Our data support the application of using the minimal levator hiatus plane and specifically the H-line as a reliable landmark to diagnose bladder descent using MR defecography imaging.
摘要：
目的：磁共振排粪成像技术已广泛用于研究盆底功能和诊断盆腔器官脱垂（POP）。这项研究的目的是探讨H线检测膀胱下降的诊断准确性，与当前的标志相比，耻骨尾线（PCL）。
方法：在这项回顾性队列研究中，我们招募了在我们的医疗中心接受MR排粪造影并通过放射学测量诊断为中度至重度膀胱膨出的患者.每个受试者的一个休息图像和一个最大疏散图像用于以下测量：膀胱基部与生殖器裂孔（GH）的垂直距离，指示临床上显著的膀胱下降，PCL作为当前放射学参考线，和H线，或者最小的提肌裂隙线，指示盆底肌肉和结缔组织支持。如果“膀胱基底”达到GH的1厘米或更低的范围内（II期或更高的膀胱膨出），则将受试者归类为具有临床意义的膀胱膨出。进行比较以评估参考线相对于GH测量的差异和预测能力。
结果：包括70名受试者，30基于到GH的距离具有临床上显著的膀胱下降。膀胱下降的女性年龄较大（64.0±11.8vs51.2±15.6，p<0.001），增加了奇偶校验(3[1-7]对2[0-5]，p=0.009),并且膀胱在休息时下降低于H线（1.9±0.5vs2.2±0.4，p=0.003）和排空（-2.4±1.6vs-0.7±1.1，p<0.001）。多元回归分析证实，年龄，疏散时H线的长度，休息时H线和膀胱最低点之间的垂直距离，排空时膀胱最低点的PCL与膀胱下降显着相关。接收器工作特性分析用于确定测量阈值，以诊断两种测量结果的临床上显着的膀胱膨出。膀胱基底至H线：-1.2（80.0，72.5）曲线下面积（AUC）0.82，膀胱基底PCL：-3.3（77.8，79.5）AUC0.86。
结论：我们的数据支持使用最小提上肌裂孔平面，特别是H线作为可靠的标志，使用MR排粪造影成像诊断膀胱下降。
方法：在这项回顾性队列研究中，我们招募了在我们的医疗中心接受MR排粪造影并通过放射学测量诊断为中度至重度膀胱膨出的患者.每个受试者的一个休息图像和一个最大疏散图像用于以下测量：膀胱基部与生殖器裂孔（GH）的垂直距离，指示临床上显著的膀胱下降，PCL作为当前放射学参考线，和H线，或者最小的提肌裂隙线，指示盆底肌肉和结缔组织支持。如果“膀胱基底”达到GH的1厘米或更低的范围内（II期或更高的膀胱膨出），则将受试者归类为具有临床意义的膀胱膨出。进行比较以评估参考线相对于GH测量的差异和预测能力。
结果：包括70名受试者，30基于到GH的距离具有临床上显著的膀胱下降。膀胱下降的女性年龄较大（64.0±11.8vs51.2±15.6，p<0.001），增加了奇偶校验(3[1-7]对2[0-5]，p=0.009),并且膀胱在休息时下降低于H线（1.9±0.5vs2.2±0.4，p=0.003）和排空（-2.4±1.6vs-0.7±1.1，p<0.001）。多元回归分析证实，年龄，疏散时H线的长度，休息时H线和膀胱最低点之间的垂直距离，排空时膀胱最低点的PCL与膀胱下降显着相关。接收器工作特性分析用于确定测量阈值，以诊断两种测量结果的临床上显着的膀胱膨出。膀胱基底至H线：-1.2（80.0，72.5）曲线下面积（AUC）0.82，膀胱基底PCL：-3.3（77.8，79.5）AUC0.86。
结论：我们的数据支持使用最小提上肌裂孔平面，特别是H线作为可靠的标志，使用MR排粪造影成像诊断膀胱下降。
