For patients with early-stage low-risk uterine cervical cancer ≤2cm, simple hysterectomy is recommended, and this can now be considered the new standard of care.1 However, for patients with cervical cancer >2cm with "non-SHAPE" criteria, radical hysterectomy is still recommended as the standard primary treatment.2. Nerve-sparing radical hysterectomy requires deep knowledge of pelvic neurovascular anatomy. Lack of proper anatomical knowledge and adequate surgical skills are associated with not only the risk of hypogastric nerve injury but also unnecessary bleeding during surgery, which may lead to unintentionally less radical surgery. We performed nerve-sparing radical hysterectomy (Querleu-Morrow classification: type C13) using the following eight steps (Video). In Japan, total laparoscopic radical hysterectomy is performed under the public health insurance system. Step 1: Development of the lateral pararectal space and the paravesical space. Step 2: Isolation of the ureter and separation of the hypogastric nerve. Step 3: Development of the rectovaginal space. Step 4: Dissection of the anterior leaf of the vesicouterine ligament. Step 5: Development of the paravaginal space and dissection of the posterior leaf of the vesicouterine ligament Fig. 1). Step 6: Separation of the cut end of the deep uterine vein from the pelvic splanchnic nerve (Fig. 2). Step 7: Transection of the uterine branch from the inferior hypogastric plexus and ligation of the paracolpium. Step 8: Vaginal cuff creation and transection of the vaginal wall. Surgeons should recognize the importance of developing a retroperitoneal avascular space based on precise anatomical landmarks, and each surgical step must be reproducible. Fig. 1 Anatomical relationships between the posterior leaf of the vesicouterine ligament and the paravaginal space (Left side). (A) and (B) The surgical forceps can easily penetrate the paravesical space. This space is known as the "paravaginal space." (C) After development of the paravaginal space, the posterior leaf of the vesicouterine ligament can be dissected. Fig. 2 Anatomical relationships between deep uterine vein, hypogastric nerve and bladder branch (right side). (A) The bladder branch from the inferior hypogastric plexus can be identified when the cut end of the deep uterine vein is cranially retracted. (B) Dot line: dissection line.

Penile inversion vaginoplasty is the most commonly performed gender-affirming surgery in transgender women and results in the creation of a neovaginal canal while preserving several pelvic structures, including the urethra, prostate, and elements of erectile tissue. However, postoperative pelvic floor anatomy in transgender women has not been well characterized using functional imaging techniques. The aim of this study was to describe pelvic floor anatomy on transperineal ultrasound in transgender women after penile inversion vaginoplasty and to evaluate the feasibility and interobserver reproducibility of selected ultrasound measurements. This pilot cross-sectional study included transgender women who had undergone penile inversion vaginoplasty at least 6 months prior to evaluation. Participants underwent a standardized transperineal pelvic floor ultrasound. Anatomical landmarks, including the urethra, bladder, prostate, residual erectile tissue, neovagina, anal canal, and levator ani muscle, were identified in the midsagittal plane. Measurements included urethral length and thickness, urethral angle, bladder neck position, rectal ampulla position, detrusor thickness, postvoid residual volume and neovaginal parameters. Ultrasound volumes were analyzed offline by two independent observers blinded to clinical data. Interobserver reproducibility was assessed using intraclass correlation coefficients (ICC). Ten participants were included. Pelvic floor structures were consistently identifiable on transperineal ultrasound in all participants. The urethra, prostate, neovaginal canal, and residual erectile tissue could be reliably visualized in the midsagittal plane. Quantitative measurements demonstrated good to excellent interobserver reproducibility for most parameters (ICC: 0.72-0.99). The spatial relationship between the neovagina, urethra, and rectum could be clearly assessed, allowing characterization of the postoperative pelvic floor configuration. Pelvic floor ultrasound is a feasible and reproducible imaging modality for the evaluation of pelvic floor anatomy in transgender women after penile inversion vaginoplasty. This technique enables detailed visualization of the neovagina and adjacent pelvic structures and may represent a useful tool for postoperative anatomical assessment and for the investigation of lower urinary tract and pelvic floor symptoms in this population. Not applicable. This study is an observational pilot study and was not registered as a clinical trial.

Population-Specific 3D/4D Transperineal Ultrasound Reference Values and Cutoffs Associated With Pelvic Organ Prolapse in Chinese Women.

Deep infiltrating endometriosis (DIE) is a rare and severe subtype of endometriosis that can cause marked distortion of pelvic anatomy. Diagnosis becomes particularly challenging when it presents as an acute abdomen with significantly elevated tumor marker levels. In this study, we describe a rare and deceptive presentation of acute abdomen caused by severe DIE that closely mimicked ovarian carcinoma. A 42-year-old woman (gravida 1, para 1) was admitted with sudden-onset severe diffuse abdominal pain lasting 5 hours. Preoperative findings-including cancer antigen 125 and carbohydrate antigen 19-9 were both elevated to approximately 20-fold above the upper limit of normal, along with imaging results-strongly suggested a ruptured malignant ovarian tumor. Intraoperatively, the lesions were indistinguishable from advanced ovarian cancer, and a definitive diagnosis of deep infiltrating endometriosis (American Society for Reproductive Medicine score 178, Stage IV) was confirmed only through postoperative histopathological examination. Her postoperative recovery was unremarkable, with rapid symptomatic relief, and no recurrence was observed during follow-up. This case highlights that deep infiltrating endometriosis should be considered in patients presenting with acute abdomen, even when clinical and biochemical features strongly suggest pelvic malignancy. Furthermore, the emergency surgery for definitive diagnosis and radical resection also achieved excellent therapeutic outcomes.

Pelvic exenteration (PE) is a complex, potentially curative option for locally advanced or recurrent pelvic malignancies in which achieving an R0 margin is paramount. This clinical review provides a pragmatic, anatomy-driven framework to optimize preoperative assessment and multidisciplinary planning. Using a compartment-based schema-central, anterior, posterior, and lateral-the article maps tumour spread to structures that determine technical feasibility and functional outcomes. For each compartment, surgical implications and reporting "pearls and pitfalls" are summarized to ensure radiological interpretation directly informs surgical decision-making. Special attention is given to differentiating tumour infiltration from post-treatment fibrosis, particularly following chemoradiotherapy, where diffusion-weighted MRI plays an important role in the attempt to differentiate residual disease from fibrosis and defining safe resection planes. The review outlines assessment of critical anatomical structures or variants that have implications for surgical planning or functional consequences for patients. In addition, reconstructive options and their imaging appearances are briefly discussed to aid postoperative assessment. Through detailed anatomical analysis and structured, compartment-based reporting, radiologists can enhance multidisciplinary communication, refine patient selection, anticipate morbidity, and ultimately increase the likelihood of achieving complete resection in pelvic exenteration.

Robotic-assisted surgery has become an established technique for rectal cancer, providing enhanced visualization and precision. However, the learning curve for robotic-assisted low anterior resection remains steep due to complex pelvic anatomy and technical challenges. Proctoring-supervised instruction by an experienced surgeon-has been introduced to facilitate early skill acquisition, yet its quantitative impact on robotic-assisted surgery remains unclear. This multicenter retrospective study included 131 patients who underwent robotic-assisted low anterior resection or ultra-low anterior resection for lower rectal cancer between July 2018 and June 2024. Patients were divided into two groups: those who underwent surgery at facilities with and without a certified proctor (Proctor group, n = 58; Non-proctor group, n = 73). Operative outcomes, console time to rectal transection, and learning curves were analyzed using linear regression and cumulative sum analysis. The Proctor group demonstrated significantly shorter operative and console times compared to the Non-proctor group (257 vs. 323min, p < 0.001; 154 vs. 184min, p < 0.001). In the first 10 cases, console times were markedly shorter in the Proctor group, indicating greater operative efficiency in the early phase. Cumulative sum analysis showed that the curve reached its peak at13 cases in the Proctor group and 16 cases in the Non-proctor group, indicating earlier stabilization of console time in the Proctor group. No significant differences were observed in complication rates or oncologic parameters between the groups. Structured proctoring was associated withshorter console times and earlier stabilization of console time during the initial phaseof robotic-assisted low anterior resection. Although the overall rate of improvement and long-term outcomes were comparable between groups, structured proctoring may help improve operative efficiency during the early stages of program implementation.

Superior gluteal vein entrapment: targeted surgical decompression for aberrant anatomy.

Previous urologic surgeries, including prostatectomy and cystectomy, are associated with an increased risk of inguinal hernia and may complicate subsequent hernia repair due to adhesions and altered pelvic anatomy. However, evidence regarding the optimal surgical approach and outcomes in this population remains limited and inconsistent. This study aimed to investigate the outcomes of inguinal hernia surgery in patients with and without a history of urologic surgery and to examine evolving surgical trends over time. This single-center retrospective cohort study included adult male patients (≥ 18 years) who underwent primary inguinal hernia repair between January 2010 and December 2024. Patients were categorized according to a history of prior urologic surgery involving retropubic dissection. The primary outcome was the postoperative complication rate, and the secondary outcomes was hernia recurrence. Multivariate regression analyses were performed to identify factors associated with outcomes. Among 927 patients included in the analysis (826 without and 101 with prior urologic surgery), there were no significant differences in postoperative complication rates between groups (22.8% vs. 24.0%, p = 0.805), nor recurrence rates (1.0% vs. 4.2%, p = 0.186). However, operative time was significantly longer in the urologic group (87.0 vs. 68.4min, p < 0.001). Multivariable analysis showed that prior urologic surgery was independently associated with longer operative time but not with increased postoperative complications or recurrence. Open repair was more common in the urologic group (51.5%), while the totally extraperitoneal approach (TEP) was rarely used (2.0%). Over time, the transabdominal preperitoneal approach (TAPP) became the predominant approach in this population (46.5%). Inguinal hernia repair in patients with a history of urologic surgery is safe and effective, with postoperative outcomes comparable to those in patients without such a history. Despite the increased technical complexity and longer operative times, minimally invasive approaches can be performed reliably in experienced centers.

Background: Retroperitoneal surgical corridors, particularly in robotic-assisted partial nephrectomy and donor surgery, require precise knowledge of hilar vascular orientation. The typically described Vein–Artery–Pelvis (VAP) anatomy is often assumed, yet its reliability is poorly quantified. Therefore, the purpose of the present study is to provide a comprehensive radioanatomical map of hilar architecture to enhance surgical safety and predictability. Methods: Contrast-enhanced computed tomography (CT) scans of the abdomen from 200 patients (104 males and 96 females) were evaluated. The anterior-to-posterior sequence of hilar structures, the frequency of early vascular branching, and the presence of accessory vessels were documented and stratified by sex and laterality. Results: The conventional VAP sequence was observed in a minority of cases, occurring in only 32.6% (131 sides). The map identified 37 distinct sequence variants. The most common variants included VAPA (9.0%), AVAP (7.8%), and VAAP (7.0%). Adherence to typical VAP anatomy was significantly lower in males (27.9%) than in females (37.7%). Arterial complexity, characterized by early branching or accessory vessels, was present in 43.2% of sides, with a significantly higher occurrence in males and on the right side. Venous mapping revealed a marked lateral disparity; accessory veins were predominantly right-sided (12.5%), whereas early venous branching was predominantly a left-sided feature (30.0%). Conclusions: Renal hilar architecture demonstrates substantial variability, with the classical VAP configuration representing a minority arrangement. These findings highlight the importance of individualized preoperative imaging assessment and may help anticipate anatomical complexity in retroperitoneal surgery.

Transabdominal retrieval of oocytes when transvaginal access is not an option: mastering an egg-cellent technique.

Deep infiltrating endometriosis and oncologic radical pelvic surgeries pose a significant risk of nerve damage. A thorough understanding of pelvic anatomy is essential for surgical precision and to avoid neurological complications or dysfunctions. Laparoscopic cadaveric dissections, with their magnification and bloodless dissection advantages, provide a safe and effective training method for mastering pelvic neuroanatomy and refining surgical skills.

Endometriosis can impair natural reproduction through multiple mechanisms, including distortion of pelvic anatomy and chronic peritoneal inflammation. On this basis, surgical treatment might be reasonably expected to benefit. However, clinical evidence challenges this belief. Surgery can indeed improve natural reproduction, but real benefits are modest. The reasons for the disappointing efficacy of surgery are discussed in this review. They include the presence of 'microscopic' endometriosis, the co-occurrence of other undetected causes of infertility, the rapid reoccurrence of adhesions, the inability of surgery to interfere with underlying pathogenetic mechanisms, the frequent recurrence of endometriotic lesions, and the association with other gynecological conditions that cannot be effectively treated with surgery (such as adenomyosis). On the other hand, the frequently discussed ovarian reserve injury may not be a determining factor (even if of utmost relevance for ART), and the strength of the evidence linking superficial peritoneal disease, ovarian endometriomas, and deep endometriosis to infertility is rather debatable. In conclusion, surgery for infertile women with endometriosis remains an option, but it cannot intrinsically ensure high rates of reproductive success. Realistic and comprehensive information on safety, effectiveness, and alternatives must be given for valid shared decision-making.

Transperineal ultrasound (TPUS) is a valuable imaging tool for evaluating patients with a variety of pelvic floor disorders, including pelvic organ prolapse (POP). Currently, calculating measurements of anatomical structures and relationships as well as extracting the mid-sagittal (MS) plane of 2D and 3D ultrasound images are obtained manually, which is a time-consuming process and requires a reviewer with prior training in pelvic floor US interpretation. The need for manual analysis of ultrasound images has limited the broader adoption of TPUS for evaluating pelvic floor disorders in both research and clinical practice. An automated segmentation and plane extraction method would improve the ability to easily quantify pelvic anatomy relevant to pelvic floor disorders and improve the efficiency and reproducibility of POP diagnosis and treatment. To develop a fast, reproducible, and automated method of acquiring the MS plane, plane of minimal hiatal dimensions (PMHD), and segmentations of the pelvic floor organs from 3D TPUS images. Our method used a nnU-Net segmentation model to segment structures of interest in the 3D TPUS images. The model segmented the pubis symphysis (PS), urethra, bladder, rectum, rectal ampulla, and anorectal angle (ANA). The segmented output was then fed into a heuristics-based method to determine the PS and ANA to extract the MS plane and PMHD automatically. We used a dataset consisting of 161 3D TPUS images from 104 patients. 89 of the volumes were acquired in a resting state and 72 during the Valsalva maneuver. The segmentation and plane extraction algorithms were evaluated by comparing the results with manual segmentations and manual plane extraction methods using the dice similarity coefficients (DSC), mean absolute surface distance (MAD), and absolute angle difference (AAD), respectively. The Wilcoxon-signed rank statistical test was used with Bonferroni-correction to p<0.01. Cohen effect size was used for comparing model results. The nnU-Net segmentation model reported an average DSC(%) of 70.4%, 58.5%, 57.1%, 48.9%, 39.0%, and 19.8% for bladder, rectum, PS, urethra, ANA, and rectal ampulla respectively. The nnU-Net segmentation model achieved significantly higher DSC (p<0.01) for the urethra and rectum than all other tested models. Across all metrics, the nnU-Net segmentation model achieved an average effect size of 0.3, 0.5, 0.7, and 0.8 compared to a 3D ResNet34 + U-Net, 3D U-Net, 2D U-Net, and Attention 3D U-Net model, respectively. The average AADs between the automatically calculated plane slices and manually estimated planes dataset for the MS plane and PMHD were 3.8° and 2.4°, respectively. The PS and ANA segmentation centroids were used to calculate the MS plane and PMHD and they had distance errors of 3.6mm and 4.4mm. We developed an automated 3D segmentation and multiple plane extraction method of female pelvic floor 3D US images. Our method extracts the MS plane and PMHD from 3D US images. The proposed algorithm pipeline can improve the efficiency and reproducibility of TPUS analysis for pelvic floor disorder diagnosis and treatment.

This study aims to evaluate the post-reconstruction pelvic anatomy on MRI in the long-term follow-up of patients with anorectal malformations (ARMs) and to explore associations between MRI findings and functional outcomes. From January 2023 to June 2025, adolescents aged 12 to 18 with ARM underwent MRI and completed a functional outcome questionnaire. The position of the rectum and neoanus, pelvic floor muscle development, anorectal angle, rectal diameter, remnant of the original fistula (ROOF), fat interposition, perirectal fibrosis, and incidental findings were assessed. MRI findings were compared between simple and complex ARMs, and associations with functional outcomes were explored. Forty-seven patients underwent MRI (21 simple, 25 complex, and one unknown ARM type). MRI displayed a ROOF in 3/47 patients (6.4 %), a rectal diameter >50 mm in 4/47 (8.5 %), and previously unrecognized gynecological anomalies in 5/6 (83.3 %) cloacal malformation patients. Compared with simple ARMs, complex cases more frequently showed lateral rectal displacement at the puborectal muscle level (32 % vs 0 %, p = 0.005) and intermediate/poor puborectal muscle development (68 % vs 14.3 %, p < 0.001), and demonstrated a wider median anorectal angle (136° [IQR 118.5-150] vs 119° [IQR 104.5-140], p = 0.037). In simple ARM without tethered cord or sacrococcygeal anomalies, fat interposition was associated with difficulty withholding defecation (p = 0.027), and perirectal fibrosis with reduced urge sensation (p = 0.022). This study highlights the value of MRI during the long-term follow-up of patients with ARM, as it detects previously unrecognized anomalies, provides new leads for improving functional outcomes, and supports a well-informed transition to adult care with optimized functional outcomes.

The global incidence of rectal cancer is rising, accompanied by the increasing use of neoadjuvant chemoradiotherapy. Although this approach improves oncological outcomes, it frequently increases operative difficulty during rectal resection. Achieving a negative circumferential resection margin (CRM) remains critical to reducing local recurrence. While clear margins are often attainable utilising the standard total mesorectal excision (TME) plane, dissection beyond TME is increasingly required following neoadjuvant radiation or for locally advanced or recurrent disease. Such surgery demands detailed knowledge of complex pelvic anatomy and sound operative strategies to achieve optimal outcomes. This publication presents a novel 'onion peel' approach to pelvic anatomy comprising five sequential layers. Layer 1-the TME plane; Layer 2-the ureterohypogastric fascia and anterior viscera; Layer 3-lymphovascular structures; Layer 4-neural structures and Layer 5-musculoskeletal anatomy. Within each layer, key anatomical features are outlined alongside practical operative strategies to facilitate safe dissection and recognition of vital structures. This paper provides colorectal surgeons with a novel overview of the anatomy surrounding the mesorectal envelope along with simple operative strategies to enter and safely dissect planes beyond TME.

Although distance from the inferior tumor edge to the anal verge (DTAV) is a key predictor for sphincter-preserving surgery (SPS) in mid-low rectal cancer, its utility is limited in the "decision-gray zone" (DTAV, 3-8 cm). Therefore, this study aimed to develop and validate a multiparametric magnetic resonance imaging-based nomogram for individualized preoperative prediction of SPS feasibility. This dual-center retrospective study included 335 patients with rectal adenocarcinoma (DTAV 3-8 cm). Patients were divided into training (n=263) and external validation (n=72) cohorts, and predictors were identified using multivariate logistic regression analysis. Model discrimination was assessed using area under the receiver operating curve (AUC) and calibration via the Hosmer-Lemeshow test. Subgroup analyses were performed across DTAV strata. Four independent predictors were identified: larger DTAV [odds ratio (OR) =5.00, P<0.001)], larger pubococcygeal overlap distance (PCOD) (OR=1.08, P=0.001), transverse diameter of mesorectal fat (TMS) (OR=1.07, P=0.017), and subcutaneous adipose tissue thickness (SAT) (OR=0.94, P=0.016). The Sphincter Preservation Assessment in Rectal Cancer (SPARC) nomogram achieved an AUC of 0.928 [95% confidence interval (95% CI): 0.890-0.956] in the training cohort, outperforming DTAV alone (AUC=0.884, P=0.031) and maintaining an AUC of 0.916 (95% CI: 0.827-0.969) in external validation. Subgroup analysis showed notably improved predictions in the 5-8 cm DTAV subgroup. Decision curve analysis demonstrated a pronounced net clinical benefit across a wide range of threshold probabilities. Interobserver agreement was excellent (intraclass correlation coefficient, 0.890-0.997). The SPARC nomogram reliably predicted SPS feasibility by integrating tumor location with pelvic anatomy and fat distribution. This provides valuable and evidence-based preoperative guidance, especially within the DTAV 3-8 cm gray zone.

Key pelvic nerve anatomy regarding low anterior resection syndrome: a surgical demonstration for nerve preservation in pelvic surgery.

Introduction: Large abdominopelvic cystic masses in post-hysterectomy patients present significant diagnostic challenges due to altered pelvic anatomy and overlapping radiological features. Peritoneal inclusion cysts may closely mimic ovarian neoplasms on imaging, leading to diagnostic uncertainty. Presentation of Case: A 55-year-old woman, eight years post vaginal hysterectomy, presented with progressive abdominal distension and abdominal discomfort. Clinical examination revealed a large cystic mass occupying the lower and central abdomen. Routine laboratory investigations and tumor markers, including CA-125 and CEA, were within normal limits. Magnetic resonance imaging suggested a peritoneal inclusion cyst, and both ovaries could not be clearly visualized. Diagnostic laparoscopy failed to identify the origin of the lesion, necessitating conversion to exploratory laparotomy. A giant cystic mass arising from the left ovary was excised in toto, along with right salpingo-oophorectomy. Histopathological examination confirmed benign mucinous cystadenoma of the left ovary. Discussion: Giant ovarian mucinous cystadenomas may lose their typical adnexal appearance and present as diffuse abdominopelvic cystic masses, particularly in patients with prior pelvic surgery. Limitations of imaging modalities and distorted pelvic anatomy contribute to frequent misdiagnosis. This case emphasizes the importance of maintaining clinical suspicion and considering surgical exploration when radiological findings are inconclusive. Conclusion: Ovarian mucinous cystadenomas should be considered in the differential diagnosis of large abdominopelvic cystic masses in post-hysterectomy patients. Timely surgical intervention remains essential for definitive diagnosis and effective management.

To elucidate the urethral closure mechanism during abdominal pressure in men, we investigated changes in pelvic anatomy during abdominal pressure using dynamic Magnetic Resonance Imaging (MRI). This study retrospectively analyzed data from 145 patients scheduled for robot-assisted radical prostatectomy at Kanazawa University Hospital from 2016 to 2022. Preoperative dynamic MRI was used to take measurements at several anatomical points to assess changes in pelvic anatomy during abdominal pressure. Dynamic MRI measurements during abdominal pressure revealed that the prostate apex rotates anteriorly at an average of 5.6°, and the internal urethral orifice shifts dorsally. Additionally, the prostate apex moves 1.2 mm toward the pubic bone. Conversely, the distal end of the membranous urethra shifts 0.9 mm dorsally during abdominal pressure. Consequently, a misalignment between the prostate apex and the membranous urethra is observed, resulting in the closure of the anterior-posterior direction of the proximal membranous urethra that may contribute to urethral closure during abdominal pressure. These results may suggest that prostate rotation during abdominal pressure creates a step-like displacement at the proximal membranous urethra, which could contribute to urethral closure in men with an intact prostate. Dynamic MRI provides anatomical evidence supporting a complementary role of prostate motion in this mechanism. Not applicable. This study was conducted prospectively with written informed consent and institutional ethical approval; however, it was not designed as a clinical trial because it was a non-interventional observational study in which a specialized MRI protocol was added to standard clinical imaging without any therapeutic intervention or treatment allocation.

Biomechanical Analysis of female pelvic floor anatomy: A novel integrative framework