
==== Front
Medicine (Baltimore)
Medicine (Baltimore)
MD
Medicine
0025-7974
1536-5964
Lippincott Williams & Wilkins Hagerstown, MD

39252301
MD-D-24-04342
00088
10.1097/MD.0000000000039259
3
4500
Research Article
Observational Study
Clinical value of transperineal ultrasound in evaluating the diagnostic grade of rectocele in Chinese women with obstructed defecation syndrome: An observational study
https://orcid.org/0000-0002-4188-2498
Jiang Yunlin MM jiang_yunlin@163.com
ab
Fan Zhimin MM Fanzm711@163.com
a
Gao Ling MM gaoling035@sina.com
a
Shen Guangshu MM doctorsgs@163.com
a
Yue Jingjing MM 753021806@qq.com
a
Wang Xiaofeng PhD wxf_1982@163.com
a
Zheng Xueping PhD zhengxp@njucm.edu.cn
a
https://orcid.org/0000-0001-6060-6838
Xue Yahong PhD a*
a Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese Medicine, Nanjing, China
b Nanjing University of Chinese Medicine, Nanjing, China.
* Correspondence: Yahong Xue, Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese Medicine, Nanjing, China (e-mail: xueyahong_1983@126.com).
06 9 2024
06 9 2024
103 36 e3925923 4 2024
27 6 2024
19 7 2024
Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.
2024
https://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial License 4.0 (CCBY-NC), where it is permissible to download, share, remix, transform, and buildup the work provided it is properly cited. The work cannot be used commercially without permission from the journal.

We aimed to evaluate the effectiveness of transperineal ultrasound (TPUS) in diagnosing rectocele, rectal intussusception (RI), enterocele, perineal descent (PD), and cystocele in Chinese women with obstructed defecation syndrome (ODS), and to determine the grading of rectocele via TPUS. Between January 2019 and December 2021, 107 obstructed defecation syndrome patients, with a mean age of 49.76 years, received TPUS and defecation proctography (DEP). Both methods were used to diagnose anorectal angle, rectocele, RI, enterocele, and PD, while cystocele and uterine prolapse were diagnosed only through TPUS. Agreement between DEP and TPUS diagnostic results was compared using Cohen kappa statistics. Seventy-six rectoceles were reported following DEP and 72 after TPUS. DEP detected 7 enteroceles, 6 of which were diagnosed simultaneously by TPUS. 43 patients presented dyssynergic defecation (DD) upon DEP, while 51 upon TPUS. DEP and TPUS detected PD in 13 and 11 patients respectively, and RI in 82 and 73, respectively. Rectocele (kappa = 0.738), RI (kappa = 0.711), DD (kappa = 0.774), enterocele (kappa = 0.847), and PD (kappa = 0.625) were obtained by Cohen kappa statistics, which indicated a good agreement between DEP and TPUS. The cutoff values for the diagnosis of moderate and severe rectocele with TPUS were 12.05 mm (AUC: 0.941) and 18.50 mm (AUC: 0.977), respectively. The DEP-determined and TPUS-determined anorectal angles were significantly correlated in the resting and Valsalva states (P < .01). Compared with DEP, while maintaining good agreement in detecting rectocele, RI, DD, enterocele, and PD, TPUS is a repeatable and noninvasive alternative. Threshold values of 12.05 mm and 18.50 mm on TPUS may diagnose moderate and severe rectocele, respectively.

defecation proctography
obstructed defecation syndrome
rectocele
transperineal ultrasound
OPEN-ACCESSTRUE
SDCT
==== Body
pmc1. Introduction

Chronic constipation is one of the common clinical gastrointestinal diseases, with 15% of the population having complaints of constipation worldwide.[1] Approximately half of patients with chronic constipation suffer from obstructed defecation syndrome (ODS). ODS is associated with the difficulty in evacuating stools, leading to straining during defecation, the sensations of incomplete evacuation, or the need to manually assist defecation.[2] ODS is a distressing condition which, despite its benign prognosis, can severely affect the patients’ quality of life.[3] Moreover, rectocele, enterocele, rectal intussusception (RI), perineal descent (PD), and dyssynergic defecation (DD) have been recognized as the main causes of ODS.[4] According to the survey, the overall prevalence of pelvic organ prolapse (POP) in urban Chinese women is 9.67%, with a rate of 26.11% in women over 70 years old.[5] According to a study by the National Health and Nutrition Examination Survey (NHANES) in the United States, the prevalence of POP in American women is 2.9%.[6] A survey in Tanzania shows that as many as 64.6% of women suffer from POP.[7]

In the past 60 years, defecation proctography (DEP) has been established as the gold standard test for evaluating functional defecation disorders, which is also considered as the standard to assess the anatomy and function of the anorectum in patients with constipation.[8] Conventionally, DEP is performed with patients in a sitting position and barium paste as the rectal contrast. However, the act of defecation in front of staff could be embarrassing. In addition, since barium enema is required during the examination, the subject may be exposed to ionizing radiation for several minutes, which can damage the human body.[9]

Rectocele refers to the gradual herniation of the anterior wall in the rectum into the posterior wall of the vagina, which leads to the swelling and prolapse of the mucosa of the posterior vaginal wall.[10] Herein, it is crucial to determine the degree of rectocele, especially when surgery has been taken into account. Given the significant impact on treatment planning and surgical outcomes, accurately assessing the severity of rectocele is essential, particularly in the context of considering surgical intervention.[11,12] DEP is known to overdiagnose the conditions in asymptomatic volunteers and has significant interobserver variability.[13] Pelvic floor ultrasound is a noninvasive and radiation-free examination with benefits of simplicity, speed, good tolerance, and suitability for clinical practice.[14] A previous study has underlined a strong association between transperineal ultrasound (TPUS) and DEP for the evaluation of posterior compartment disorders.[15] Compared with DEP, TPUS provides more information about the disorders within anterior and central compartment. Currently, the grading of rectocele in TPUS in Chinese women remains poorly defined. Furthermore, since rectocele is commonly an indication for surgery, it is critical to determine the cutoff values for rectocele on TPUS.

In light of this, the current study aimed to analyze the accuracy of TPUS in the diagnosis of rectocele and to compare it with that of DEP, with a focus on determining the grading of rectocele via TPUS in Chinese women.

2. Material and methods

2.1. Study population

This prospective study was conducted at Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese Medicine. Between January 2019 and December 2021, 107 Chinese women with ODS were included in the study. The patients’ demographic and symptom data were collected including age, body mass index, parity, delivery mode, course of disease, previous surgical history, previous treatment of constipation, and Cleveland Clinic Constipation score.[16] All these patients were required to finish the examinations of DEP and TPUS. DEP was carried out as the preliminary assessment prior to TPUS in all the cases. All imaging was performed and reported by clinicians blinded to the patients’ symptom severity. All reports were verified by at least one consultant.

2.2. Ethical statement

The present study has been approved by Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese Medicine. Meanwhile, the written informed consent was obtained from all participants enrolled in this study as needed, and all patients’ complete medical records have been processed and archived in accordance with the Health Insurance Portability and Accountability Act.

2.3. Protocol for DEP and TPUS

DEP was performed by an experienced radiologist blinded to all the clinical data. One night prior to the examination, 4 g of senna leaves was taken orally for intestinal preparation. Before the commencement of examination, the patients were instructed to lie on the examination bed in the left lateral position, and approximately 450 mL of 70% barium sulfate suspension was injected into the rectum. The patients were told to sit on the defecation bucket, and the doctor was asked to observe the rectum and anal canal under fluoroscopy and select the appropriate imaging ranges, which included the sacrococcygeal bone, pubic symphysis, and anus.

The TPUS-based examinations in all the patients that had DEP performed were performed by sonographers blinded to the results of DEP and all the clinical data with a Bruel and Kjaer Pro Focus System Ultra View-2202 (Mile-parken 34, 2730 Herlev, Denmark) using a model B-K 8802 transducer equipped with a double multifrequency crystal (range: 3–6 MHz) and with at least 70° mechanical rotation at the perineum. In brief, after covering the sensor with gloves, sonographers placed the sensor on the perineum to obtain the median sagittal view. See more in Supplementary File 1, Supplemental Digital Content, http://links.lww.com/MD/N329&2 and http://links.lww.com/MD/N330.

2.4. Sensitivity and specificity detection indicators for TPUS

This research includes a total of 7 observation indicators to validate the sensitivity and specificity of TPUS, including anorectal angle, rectocele, RI, enterocele, PD, cystocele, and uterine prolapse. Detailed definitions and descriptions for these indicators are as follows:

Anorectal angle. Anorectal angle was measured between the anal canal and the tangent to the posterior border of the rectum upon the examinations of DEP and TPUS.[17] DD was diagnosed when the anorectal angle became smaller or remained unchanged in the Valsalva state compared to the resting state.[13]

Rectocele. The rectocele on DEP was defined as a bulge of the anterior rectal wall beyond the projected anterior rectal wall (Fig. 1A). A depth of ≥0.6 cm indicated the diagnosis on DEP with the severity as follows: 6 to 15 mm, mild rectocele; 16 to 30 mm, moderate rectocele; and ≥31 mm, severe rectocele.[18] The rectocele on TPUS was measured perpendicular to the expected contour of the anterior aspect of the rectal muscularis in continuity with the internal anal sphincter (significant at >1 cm) (Fig. 1b).[14]

Figure 1. (A) A rectocele (RC) on defecation proctography. (B) A rectocele (RC) on transperineal ultrasound (R: rectum; A: anal canal). (C, D) Rectal intussusception (RI) on transperineal ultrasound ((C) rectorectal; (D) rectoanal; R: rectum; A: anal canal). (E) Enterocele (EC) on defecation proctography (R: rectal). (F) Enterocele (EC) on transperineal ultrasound (R: rectum; A: anal canal; V: vagina).

Rectal intussusception. Loose rectal wall invaginated into the rectal lumen during the Valsalva maneuver. RI was graded according to the Oxford Radiological Classification[19] (grades I–II: rectorectal (normal); grades III–IV: rectoanal (pathological); grade V: rectal prolapse) (Fig. 1C and D).

Enterocele. Enterocele was diagnosed when the small bowel or rectosigmoid descended between the rectum and vagina or an enlarged rectovaginal space was visible.[20] The same evaluation method was adopted in the examination for enterocele using DEP and TPUS (Fig. 1E and F).[15]

Perineal descent. PD was determined by measuring the level of the anorectal junction (ARJ) at rest and during straining. For DEP examination, PD was diagnosed when the ARJ descended more than 3.5 cm from the subischial tuberosity plane in the Valsalva state compared to the resting position.[21] For TPUS examination, the ARJ was located below the level of the pubic symphysis in the maximum Valsalva state.[2]

Cystocele. For the diagnosis of cystocele, the bladder was located 0 to 10 mm below the level of the pubic symphysis on maximum Valsalva in TPUS examination.[22]

Uterine prolapse. Cervix descending to 15 mm above the symphysis pubis on maximum Valsalva on TPUS examination was indicative of uterine prolapse.[23]

2.5. The grading of rectocele on TPUS

In this study, we use the DEP grading system as the gold standard to categorize the severity of rectocele in patients. The DEP system, which is widely recognized for its diagnostic accuracy, classifies rectocele into various grades based on specific clinical criteria. Concurrently, we assess these patients using the TPUS scoring system. By comparing the TPUS scores with the DEP grades, we aim to evaluate the efficacy of TPUS in detecting and grading rectocele. This comparative analysis helps establish the reliability of the TPUS detection system in grading rectocele against the established DEP standard.

2.6. Statistical analysis

All statistical analyses were implemented using SPSS (version 26.0). Measurement data are expressed as mean ± standard deviation (SD). Cohen kappa coefficients were calculated to verify the agreement between TPUS and DEP during the detection of rectocele, RI, DD, enterocele, and PD. The strength of agreement was interpreted according to the Altman classification system (<0.20, poor; 0.21–0.40, fair; 0.41–0.60, moderate; 0.61–0.80, good; and 0.81–1.00, very good). The resulting model was used to estimate sensitivity, specificity, and the area under the curve (AUC) with 95% bootstrap confidence intervals.[24] The test accuracy was defined as follows: excellent (AUC 0.9–1.0), good (0.8–0.9), moderate (0.7–0.8), fair (0.6–0.7), poor (0.5–0.6), and useless (< 0.5).[25] The paired t test was used to compare the changes in the anorectal angle on DEP and TPUS examination during the resting and Valsalva states, respectively. Kruskal–Wallis tests or analysis of variance was implemented to further analyze the results of TPUS and DEP. The researchers were unaware of the DEP results, and 2 independent observers were invited to interpret the TPUS and report the kappa. The data of results were considered statistically significant when P < .05.

Receiver operating characteristic curves (ROC) classification system was used as a continuous variable to determine the cutoff values for the severity levels of rectocele, including mild, moderate, and severe. The Youden index (defined as sensitivity + specificity − 1) was used to find the maximum value for the cutoff point.[26]

3. Results

3.1. The characteristics of patients

One hundred seven patients were analyzed, with an incidence of ODS at 100%. Average age of the participants was 50 years (range: 22–74), with a mean body mass index of 22.25 kg/m². Besides, the average disease duration was 74.05 months, with a mean Cleveland Clinic Constipation score of 16.42. More information is provided in Table 1.

Table 1 Demographic details of the 107 patients.

Patient characteristics	Total (n = 107)	
Age (yrs)	49.76 ± 13.03	
Body mass index (kg/m2)	22.25 ± 2.64	
Course of disease (mo)	74.05 ± 61.80	
CCCS	16.42 ± 6.82	
Parity (n, %)	
 Nullipara	9 (8.41)	
 Unipara	62 (57.94)	
 Multipara	31 (28.97)	
 Unknown	5 (4.67)	
Mode of delivery (n, %)	
 Vaginal delivery	66 (61.68)	
 Caesarean	27 (25.23)	
Previous treatment (n, %)	
 Chinese medicine	6 (5.61)	
 Laxative	20 (18.69)	
 Manual defecation	21 (19.63)	
 Probiotics	2 (1.87)	
 Cellulose	2 (1.87)	
 Enema	7 (6.54)	
 Biofeedback	2 (1.87)	
 Two or more treatments	5 (4.67)	
 No	42 (39.25)	
Accompanying symptoms (n, %)	
 Functional anorectal pain	8 (7.48)	
Previous pelvic surgery (n, %)	
 Hysterectomy	7 (6.54)	
 Hemorrhoidectomy	8 (7.48)	
 Rectal surgery	1 (0.93)	
 Colectomy	1 (0.93)	
 Vaginal leiomyoma surgery	1 (0.93)	
 Uterine suspension surgery	1 (0.93)	
CCCS = Cleveland Clinic Constipation score.

Meanwhile, 57.94% of patients were uniparous, 28.97% were multiparous, and 8.41% were nulliparous. Regarding the mode of delivery, 61.68% of patients chose vaginal delivery and 25.23% selected cesarean section.

Furthermore, 65 patients had received previous treatment. Among them, 18.69% received laxatives, and 19.63% were assisted with manual defecation. Regarding surgical history, among the 107 patients, 7.48% had a previous hemorrhoidectomy and 7.48% had undergone a hysterectomy. More information is provided in Table 1.

3.2. The performance of various indicators on DEP and TPUS

The kappa for various indicators in this study from highest to lowest are as follows: rectocele (kappa 0.738, sensitivity 89.47%, specificity 87.10%); enterocoele (kappa 0.847, sensitivity 85.71%, specificity 99%); RI (kappa 0.711, sensitivity 87.80%, specificity 96%); dyssynergic defecation (kappa 0.774, sensitivity 95.36%, specificity 84.38%); PD (kappa 0.625, sensitivity 61.54%, specificity 96.81%). For anorectal angle, on DEP examination, the anorectal angle was 111.99 ± 11.52 (Mean ± SD) at rest and 117.39 ± 13.71 in the Valsalva state. Upon TPUS examination, the anorectal angle was 121.65 ± 9.20 at rest and 121.10 ± 13.76 in the Valsalva state. 94 (87.85%) and 88 (82.24%) patients had prolapse upon the examination of DEP and TPUS, respectively. Summarized results are provided in Table 2. More details about the performance of various indicators on DEP and TPUS are as follows:

Table 2 Consistency analysis of diagnostic results between DEP and TPUS.

	DEP (n, %)	TPUS (n, %)	PPV	NPV	Sensitivity	Specificity	Kappa	
Rectocele	
 No	31 (28.97)	35 (32.71)	94.44	77.14	89.47	87.10	0.738	
 Yes	76 (71.03)	72 (67.29)	
Rectal intussusception	
 No	25 (23.36)	34 (31.78)	98.63	70.59	87.80	96	0.711	
 Yes	82 (76.64)	73 (68.22)	
Dyssynergic defecation	
 No	64 (59.81)	56 (52.34)	80.39	96.43	95.35	84.38	0.774	
 Yes	43 (40.19)	51 (47.66)	
Enterocele	
 No	100 (93.46)	100 (93.46)	85.71	99	85.71	99	0.847	
 Yes	7 (6.54)	7 (6.54)	
Perineal descent	
 No	94 (87.85)	96 (89.72)	72.73	94.79	61.54	96.81	0.625	
 Yes	13 (12.15)	11 (10.28)	
DEP = defecation proctography, NPV = negative predictive value, PPV = positive predictive value, TPUS = transperineal ultrasound.

Rectocele. Seventy-six (71.03%) and 72 (67.29%) patients had rectocele upon the examination of DEP and TPUS, respectively. The positive predictive value (PPV) of TPUS was 94.44% (68 true positives and 4 false positives), and the negative predictive value (NPV) was 77.14% (27 true negatives and 8 false negatives).

Enterocoele. About 7 (6.54%) and 7 (6.54%) patients had enterocoele following the examination of DEP and TPUS, respectively. TPUS presented a PPV of 85.71% (6 true positives and 1 false positive), NPV of 99% (99 true negatives and 1 false negative).

Rectal intussusception. There were 82 (76.64%) patients with RI following DEP examination (52 grades I–II, 30 grades III–IV, 0 grade V) and 73 (68.22%) patients with RI after TPUS examination (46 grades I–II, 27 grades III–IV, 0 grade V). The PPV of TPUS was 98.63% (72 true positives, 1 false positive), and the NPV was 70.59% (24 true negatives, 10 false negatives).

Dyssynergic defecation. Forty-three (40.19%) and 51 (47.66%) patients had DD following the examination of DEP and TPUS, respectively. The PPV of TPUS was 80.39% (41 true positives, 10 false positives), and the NPV was 96.43% (54 true negatives, 2 false negatives).

Perineal descent. Thirteen (12.15%) and 11 (10.28%) patients had PD upon DEP and TPUS examination, respectively. The PPV of TPUS was 72.73% (8 true positives, 3 false positives), and NPV was 94.79% (91 true negatives, 5 false negatives).

Anterior and middle compartments. TPUS examination had advantages in detecting the disorders of the anterior and middle compartments. 13 (12.15%) patients were found to have cystocele and 1 (0.9%) patient had uterine prolapse, which could not be recognized on DEP examination.

Anorectal angle. On DEP examination, the anorectal angle was 111.99 ± 11.52 at rest and 117.39 ± 13.71 in the Valsalva state. Upon TPUS examination, the anorectal angle was 121.65 ± 9.20 at rest and 121.10 ± 13.76 in the Valsalva state. There was a significant relationship between the anorectal angles of TPUS and DEP, and the measured values were generally higher for TPUS than for DEP in the resting (Fig. 2C) and Valsalva (Fig. 2D) states (P < .01).

Figure 2. (A) Receiver operating characteristics (ROC) curve for rectocele diagnosed via transperineal ultrasound. Area under the curve (AUC): 0.941. (B) Receiver operating characteristics (ROC) curve for rectocele diagnosed via transperineal ultrasound. AUC: 0.977. (C) Anorectal angle at rest between defecation proctography (DEP) and transperineal ultrasound (TPUS) (P < .01). (D) Anorectal angle in the Valsalva state between DEP and TPUS (P < .01).

3.3. Grading of rectocele on TPUS

The present study further demonstrated that TPUS could be used to establish the classification criteria with ROC. This classification demonstrated higher sensitivity and specificity depending on the degree of rectocele. The SD of rectocele diagnosed by TPUS was 8.45 mm. Using ROC statistics, we established optimal cutoff values of 12.05 mm for moderate rectocele and 18.50 mm for severe rectocele. The depth of rectocele was measured against ODS for the ROC statistics. The obtained AUC was 0.941 (Fig. 2A) and 0.977 (Fig. 2B) for moderate and severe rectocele, respectively.

4. Discussion

Imaging is essential for diagnosing ODS-related anatomical (RI, enterocele, rectocele, PD) and functional (loss of pelvic floor relaxation/DD) abnormalities. Our study compared TPUS and DEP, testing a wide range of pathologies with a detailed grading system. We found TPUS to be a reliable alternative to DEP for assessing ODS, providing more convincing evidence than previous studies. Good agreement has been shown between DEP and TPUS for diagnosing rectocele, RI, DD, enterocele, and PD. A previous study reported that TPUS has a sensitivity of 88% to 94% and a specificity of 86% to 95% for diagnosing rectocele.[2] In this study, using DEP as the standard, the sensitivity of TPUS for diagnosing rectocele was 89.47% and the specificity was 87.10%. These findings are consistent with previous studies. A consistency test showed substantial agreement between the 2 imaging methods (kappa 0.738). We also determined the cutoff values for rectocele indexing in TPUS: 12.05 mm for mild to moderate (AUC: 0.941) and 18.50 mm for moderate to severe rectocele (AUC: 0.977). These new cutoff values help clarify the degree of rectocele, aiding in treatment selection. Additionally, TPUS is more comfortable than DEP, requiring no preparation or harmful radiation, and exhibits good reproducibility and reliability. The results of this study showed that the diagnostic value of TPUS for rectocele was consistent with that of DEP, indicating that body position did not affect the diagnosis by TPUS. Since rectocele results from anterior and posterior lateral forces, even in the lithotomy position, gravity does not significantly influence the imaging of rectocele.[27]

Assessing the severity of rectocele is crucial in clinical practice. It aids in symptom evaluation, guides personalized treatment plans, and informs decisions between nonsurgical and surgical approaches. Understanding rectocele extent assists in surgical planning, prognosis, and monitoring treatment effectiveness. Clear severity assessment also enhances patient education, self-management, and overall treatment satisfaction.

In this study, DEP detected 7 cases of enterocele, 6 of which were also diagnosed by TPUS, yielding a diagnostic sensitivity of 85.71% and specificity of 99%. The 2 methods showed excellent diagnostic agreement (kappa 0.847). TPUS proved to be more effective in diagnosing enterocele and offers noninvasive advantages for guiding further imaging or surgical treatment. This study showed that the sensitivity of TPUS for diagnosing RI was 87.80%, with a specificity of 96%, and it achieved good agreement with DEP (kappa 0.711). Martellucci et al’s[15] research reported an agreement of 0.74 between the 2 methods. Beer-Gabel et al[28] found TPUS had a sensitivity of 82% and a specificity of 84% for RI diagnosis. Grasso et al[29] observed 68% of RI patients were symptomatic based on DEP, while 75% were symptomatic following TPUS, highlighting TPUS’s clinical relevance. No significant rectal prolapse was detected by either method in this study; these cases were diagnosed clinically based on symptoms and signs, often leading to surgical intervention.

DD is primarily due to the failure of the puborectalis muscle and external anal sphincter to relax, resulting in a small or constant anorectal angle. Thus, changes in the anorectal angle are critical for diagnosing DD. Hainsworth et al evaluated 323 female constipation patients using pelvic floor ultrasound and DEP, finding ultrasound had a sensitivity of 95% and specificity of 91%.[30] Van Gruting et al[25] reported TPUS had a sensitivity of 89% and specificity of 93% for diagnosing DD, with patients preferring TPUS over DEP and MRI. In this study, TPUS had a sensitivity of 95.35% and specificity of 84.38% for DD, showing good agreement with DEP (kappa 0.774).

PD is a common pelvic floor abnormality leading to ODS, but many studies exclude PD from their accuracy assessments. The 2 imaging methods for PD vary widely due to different reference lines, and a direct comparison of these methods is lacking.[31] In this study, using DEP as the standard, the sensitivity of TPUS for diagnosing PD was 61.54% and the specificity was 96.81%, with good agreement between the 2 methods (kappa 0.625). However, further studies are needed to clarify the definition and measurement criteria of PD in ultrasound examinations. Moreover, there was a significant association between the anorectal angles measured by TPUS and DEP in both the resting and Valsalva states, with TPUS generally yielding higher values. Since these measurements were taken from the same patients, the significant association indicates consistency between the 2 methods in measuring anorectal angles.

In addition, cystocele and uterine prolapse can be identified by TPUS but not by DEP. Previous research highlights that TPUS can observe bladder prolapse and distinguish different types of cystocele.[32] Compared to DEP, TPUS offers comprehensive static and dynamic visualization of the entire pelvic floor in ODS patients, showcasing significant advantages in availability and simplicity. Its noninvasive nature and lack of ionizing radiation allow for further investigations into the prevalence of morphological abnormalities in asymptomatic women and enable the repeatability of findings.[33]

This is the first study in China to analyze the accuracy of TPUS for diagnosing and grading rectocele in women compared to DEP. Due to ethnic differences, foreign study data have limited applicability to Chinese populations, making this study a valuable addition to domestic research. Despite challenges such as operator variance and subjective interpretation when grading rectocele with TPUS, our study shows that TPUS performs comparably to DEP in detecting RI, DD, enterocele, and PD. Given our larger patient sample size, the credibility of these findings is high. Moreover, if conservative treatment fails or surgery is considered, clinicians can opt for DEP or MRI, potentially reducing medical costs and avoiding unnecessary radiation exposure.

4.1. Limitation

However, it should be noted that this study was limited by a lack of analysis on anorectal manometry. Improving our understanding of the relationship between imaging and manometry could facilitate a more comprehensive assessment of ODS, which will be a focus of our follow-up studies. Additionally, we plan to conduct longitudinal observations over several years or use data from our database for cross-sectional analysis, situating this current study as a middle stage of a complete research project. Furthermore, since the use of TPUS in diagnosing ODS is somewhat unconventional, our findings may push the boundaries of diagnostic patterns in ODS and pave the way for future research.

5. Conclusions

In comparison to DEP, TPUS demonstrates good agreement in detecting rectocele, RI, dyssynergic defecation, enterocele, and PD, while also providing a repeatable and noninvasive alternative. Additionally, TPUS offers threshold values of 12.05 mm and 18.50 mm for diagnosing moderate and severe rectocele, respectively.

Author contributions

Data curation: Yunlin Jiang.

Formal analysis: Yunlin Jiang.

Writing – original draft: Yunlin Jiang.

Writing – review & editing: Yunlin Jiang.

Supervision: Zhimin Fan, Ling Gao, Xueping Zheng, Xiaofeng Wang, Yahong Xue.

Resources: Guangshu Shen, Jingjing Yue.

Validation: Yahong Xue.

Abbreviations:

ARJ anorectal junction

AUC area under the curve

DD dyssynergic defecation

DEP defecation proctography

NHANES National Health and Nutrition Examination Survey

NPV negative predictive value

ODS obstructed defecation syndrome

PD perineal descent

POP pelvic organ prolapse

PPV positive predictive value

RI rectal intussusception

ROC receiver operating characteristic curves

SD standard deviation

TPUS transperineal ultrasound.

The authors have no funding and conflicts of interest to disclose.

Patient consent for publication is not required for this study.

This study does not involve human participants or animal subjects.

The datasets generated during and/or analyzed during the current study are not publicly available, but are available from the corresponding author on reasonable request.

Supplemental Digital Content is available for this article.

How to cite this article: Jiang Y, Fan Z, Gao L, Shen G, Yue J, Wang X, Zheng X, Xue Y. Clinical value of transperineal ultrasound in evaluating the diagnostic grade of rectocele in Chinese women with obstructed defecation syndrome: An observational study. Medicine 2024;103:36(e39259).

Provenance and peer review is not commissioned; externally peer reviewed.
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