INTRODUCTION

Simulation based training, which is hypothesized to increase skill proficiency among trainees, is currently gaining popularity in pediatric surgical training. High-fidelity simulators are expensive and not easily replicable in low to middle income countries; thus, the use of low-fidelity simulators are being suggested. This type of educational technique may have a role in complex procedures such as pull-through procedure among patients with Hirschsprung's disease. This study aimed to ascertain the development and associated validity of low-fidelity simulators for transanal pull-through among pediatric patients.

This is a validation study of a low-fidelity simulator for transanal pullthrough in pediatric surgery. The model was assembled by carefully harvesting the anus, colon and rectum from a pig cadaver, ensuring the tissues remained intact including the perianal skin. These tissues were then mounted onto a specially designed basket that simulates the human pelvic cavity. The prototype model underwent initial testing to ensure anatomical accuracy and durability. A panel of five pediatric surgeons were tapped for content validation.

The overall validity index of the simulator was 1.00 which was high. All panel experts agreed on the anatomical realism, educational value, and alignment with training objectives. Some positive feedback on its use included its ability to accurately simulate the surgical procedure and its potential to reduce the learning curve for trainees. Another feedback is that it can help clinicians feel more prepared and comfortable when performing the procedure on actual patients after practicing on the simulator. No negative feedback were reported.

The study showed that the use of an animal simulator for practicing transanal pullthrough in pediatric surgery is feasible and valid. This model has the potential to be adapted for educational purposes and hands-on training before doing actual case surgeries. The realistic anatomy and tactile feedback provided by the simulator can help trainees improve their skills and confidence in performing transanal pullthrough.

OBJECTIVES: To investigate the characteristics and clinical significance of anorectal manometry measurements in children with tethered cord syndrome (TCS) before and after surgery. METHODS: A retrospective study was conducted on 44 children with TCS treated at the Children's Hospital of Zhejiang University School of Medicine from January 2022 to September 2023. These patients were divided into effective subgroup (n=34) and non-effective subgroup (n=10) based on postoperative symptom improvement. Additionally, 34 children with functional constipation were selected as a control group. Baseline data and manometry measurements were compared between the preoperative TCS group and the control group, as well as between the non-effective and effective subgroups. RESULTS: The TCS group had lower short contraction time and defecation relaxation rate compared to the control group (P<0.05), while defecation residual pressure and maximum rectal tolerable threshold were higher than the control group (P<0.05). The length of the anal canal in the high-pressure zone in the effective subgroup was greater postoperatively than preoperatively (P<0.05), and the initial rectal sensation threshold decreased postoperatively (P<0.05). The non-effective subgroup had lower preoperative maximum rectal expulsion pressure compared to the effective subgroup (P<0.05). Postoperative rectal anal inhibition reflex values in the effective subgroup were higher than those in the non-effective subgroup (P<0.05). CONCLUSIONS There are some differences in anorectal dynamics between children with TCS and those with functional constipation. Maximum rectal expulsion pressure may be a key predictor of surgical outcomes. Surgery can alter certain defecation functions in some children.
Humans ; Male ; Anal Canal/physiopathology* ; Female ; Rectum/physiopathology* ; Child ; Child, Preschool ; Retrospective Studies ; Manometry ; Neural Tube Defects/physiopathology* ; Infant ; Defecation ; Adolescent ; Constipation/physiopathology* ; Clinical Relevance

Tianhe procedure^® is a functional sphincter-preserving surgical approach developed for rectal cancer patients following radiotherapy. This technique involves extended proximal resection of the colon beyond the pelvic cavity, followed by anastomosis of the non-irradiated proximal colon to the distal rectum or anal canal. This strategy aims to reduce the incidence of anastomotic complications and postoperative bowel dysfunction. However, there is currently a lack of standardized practice guideline for implementing Tianhe procedure^® in China. Therefore, the Chinese Radiation Intestinal Injury Research Group, the Colorectal Surgery Group of Surgery Branch of the Chinese Medical Association, the Anorectal Branch of Chinese Medical Doctor Association, the Colorectal Cancer Committee of the Chinese Medical Doctor Association, and the Colorectal Cancer Committee of China Anti-cancer Association, and the Gastrointestinal Surgical Branch of Guangdong Medical Doctor Association, have jointly convened a panel of national experts to discuss and establish this standardized surgical procedure. This standard, based on the latest evidence from literature, research advancements, and expert experience, focuses on key aspects of the Tianhe procedure^®, including its precise definition, indications, critical procedural steps, postoperative complications, and functional rehabilitation strategies. It aims to promote standardized implementation and broader clinical adoption of this innovative surgical technique.
Humans ; Rectal Neoplasms/radiotherapy* ; Anal Canal/surgery* ; Anastomosis, Surgical/methods* ; Organ Sparing Treatments/methods* ; Rectum/surgery* ; Postoperative Complications/prevention & control* ; Digestive System Surgical Procedures/methods*

Background and Objective: One of the uses of indocyanine green (ICG) in the surgical field is the evaluation of the anastomotic margins in colorectal surgery. This is of particular importance because fluorescence imaging may aid in detecting vascular compromise, allowing the surgeon to change the resection margin thereby decreasing the chance of an anastomotic leak. To date, there has been no study with its use locally. This study aimed to determine whether the use of ICG can safely identify if the margins of resection are well-vascularized in patients undergoing left-sided colon or rectal surgery, which in turn may reduce anastomotic leak rates. Methods: Through a retrospective study design, the investigators gathered data of patients who underwent left-sided colon or rectal surgery. The groups were divided into those with and without the use of ICG and a comparative data on the anastomotic leak rates were analyzed. Results: Eighty-six (86) patients with similar patient characteristics, tumor staging, and surgical approach were compared. Both the leak rates identified during the initial hospital stay and at 30 days post-operatively were lower in those where ICG was used (p=0.035, p=0.047, respectively) than those where ICG was not used. Conclusion ICG fluorescence imaging may reduce the anastomotic leak rates in patients undergoing colorectal surgery.
indocyanine green ; colon ; rectum ; colorectal surgery ; anastomosis, surgical ; anastomotic leak

Objective: To investigate the causes and management of long-term persistent pelvic presacral space infection. Methods: Clinical data of 10 patients with persistent presacral infection admitted to the Cancer Hospital of Zhengzhou University from October 2015 to October 2020 were collected. Different surgical approaches were used to treat the presacral infection according to the patients' initial surgical procedures. Results: Among the 10 patients, there were 2 cases of presacral recurrent infection due to rectal leak after radiotherapy for cervical cancer, 3 cases of presacral recurrent infection due to rectal leak after radiotherapy for rectal cancer Dixons, and 5 cases of presacral recurrent infection of sinus tract after adjuvant radiotherapy for rectal cancer Miles. Of the 5 patients with leaky bowel, 4 had complete resection of the ruptured nonfunctional bowel and complete debridement of the presacral infection using an anterior transverse sacral incision with a large tipped omentum filling the presacral space; 1 had continuous drainage of the anal canal and complete debridement of the presacral infection using an anterior transverse sacral incision. 5 post-Miles patients all had debridement of the presacral infection using an anterior transverse sacral incision combined with an abdominal incision. The nine patients with healed presacral infection recovered from surgery in 26 to 210 days, with a median time of 55 days. Conclusions: Anterior sacral infections in patients with leaky gut are caused by residual bowel secretion of intestinal fluid into the anterior sacral space, and in post-Miles patients by residual anterior sacral foreign bodies. An anterior sacral caudal transverse arc incision combined with an abdominal incision is an effective surgical approach for complete debridement of anterior sacral recalcitrant infections.
Humans ; Reinfection ; Rectum/surgery* ; Rectal Neoplasms/surgery* ; Drainage ; Anal Canal/surgery* ; Pelvic Infection

In recent years, with advances in pelvic oncology and surgical techniques, surgeons have redefined the boundaries of pelvic surgery. Combined pelvic exenteration is now considered the treatment of choice for some patients with locally advanced and locally recurrent rectal cancer, but it is only performed in a few hospitals in China due to the complexity of the procedure and the large extent of resection, complications, and high perioperative mortality. Although there have been great advances in oncologic drugs and surgical techniques and equipment in recent years, there are still many controversies and challenges in the preoperative assessment of combined pelvic organ resection, neoadjuvant treatment selection and perioperative treatment strategies. Adequate understanding of the anatomical features of the pelvic organs, close collaboration of the clinical multidisciplinary team, objective assessment and standardized preoperative combination therapy creates the conditions for radical surgical resection of recurrent and complex locally advanced rectal cancer, while the need for rational and standardized R0 resection still has the potential to bring new hope to patients with locally advanced and recurrent rectal cancer.
Humans ; Pelvic Exenteration/methods* ; Neoplasm Recurrence, Local/surgery* ; Rectum/surgery* ; Rectal Neoplasms/surgery* ; Pelvis/surgery* ; Treatment Outcome ; Retrospective Studies

Neoadjuvant therapy has been widely applied in the treatment of rectal cancer, which can shrink tumor size, lower tumor staging and improve the prognosis. It has been the standard preoperative treatment for patients with locally advanced rectal cancer. The efficacy of neoadjuvant therapy for rectal cancer patients varies between individuals, and the results of tumor regression are obviously different. Some patients with good tumor regression even achieve pathological complete response (pCR). Tumor regression is of great significance for the selection of surgical regimes and the determination of distal resection margin. However, few studies focus on tumor regression patterns. Controversies on the safe distance of distal resection margin after neoadjuvant treatment still exist. Therefore, based on the current research progress, this review summarized the main tumor regression patterns after neoadjuvant therapy for rectal cancer, and classified them into three types: tumor shrinkage, tumor fragmentation, and mucin pool formation. And macroscopic regression and microscopic regression of tumors were compared to describe the phenomenon of non-synchronous regression. Then, the safety of non-surgical treatment for patients with clinical complete response (cCR) was analyzed to elaborate the necessity of surgical treatment. Finally, the review studied the safe surgical resection range to explore the safe distance of distal resection margin.
Humans ; Neoadjuvant Therapy/methods* ; Margins of Excision ; Treatment Outcome ; Rectal Neoplasms/pathology* ; Rectum/pathology* ; Neoplasm Staging ; Retrospective Studies

Humans ; Rectum/surgery* ; Liposarcoma/surgery* ; Biomarkers, Tumor

Objective: To methodically assess the clinical effectiveness and safety of robot-assisted total rectal mesenteric resection (RTME), laparoscopic-assisted total rectal mesenteric resection (laTME), and transanal total rectal mesenteric resection (taTME). Methods: A computer search was conducted on PubMed, Embase, Cochrane Library, and Ovid databases to identify English-language reports published between January 2017 and January 2022 that compared the clinical efficacy of the three surgical procedures of RTME, laTME, and taTME. The quality of the studies was evaluated using the NOS and JADAD scales for retrospective cohort studies and randomized controlled trials, respectively. Direct meta-analysis and reticulated meta-analysis were performed using Review Manager software and R software, respectively. Results: Twenty-nine publications comprising 8,339 patients with rectal cancer were ultimately included. The direct meta-analysis indicated that the length of hospital stay was longer after RTME than after taTME, whereas according to the reticulated meta-analysis the length of hospital stay was shorter after taTME than after laTME (MD=-0.86, 95%CI: -1.70 to -0.096, P=0.036). Moreover, the incidence of anastomotic leak was lower after taTME than after RTME (OR=0.60, 95%CI: 0.39 to 0.91, P=0.018). The incidence of intestinal obstruction was also lower after taTME than after RTME (OR=0.55, 95%CI: 0.31 to 0.94, P=0.037). All of these differences were statistically significant (all P<0.05). There were no statistically significant differences between the three surgical procedures regarding the number of lymph nodes cleared, length of the inferior rectal margin, or rate of positive circumferential margins (all P>0.05). An inconsistency test using nodal analysis revealed no statistically significant differences between the results of direct and indirect comparisons of the six outcome indicators (all P>0.05). Furthermore, we detected no significant overall inconsistency between direct and indirect evidence. Conclusion: taTME has advantages over RTME and laTME, in terms of radical and surgical short-term outcomes in patients with rectal cancer.
Humans ; Robotics ; Robotic Surgical Procedures/adverse effects* ; Network Meta-Analysis ; Retrospective Studies ; Postoperative Complications/etiology* ; Transanal Endoscopic Surgery/methods* ; Rectum/surgery* ; Rectal Neoplasms/pathology* ; Laparoscopy/methods* ; Treatment Outcome

Objective: To document the anatomical structure of the area anterior to the anorectum passing through the levator hiatus between the levator ani slings bilaterally. Methods: Three male hemipelvises were examined at the Laboratory of Clinical Applied Anatomy, Fujian Medical University. (1) The anatomical assessment was performed in three ways; namely, by abdominal followed by perineal dissection, by examining serial cross-sections, and by examining median sagittal sections. (2) The series was stained with hematoxylin and eosin to enable identification of nerves, vessels, and smooth and striated muscles. Results: (1) It was found that the rectourethralis muscle is closest to the deep transverse perineal muscle where the longitudinal muscle of the rectum extends into the posteroinferior area of the membranous urethra. The communicating branches of the neurovascular bundle (NVB) were identified at the posterior edge of the rectourethralis muscle on both sides. The rectum was found to be fixed to the membranous urethra through the rectourethral muscle, contributing to the anorectal angle of the anterior rectal wall. (2) Serial cross-sections from the anal to the oral side were examined. At the level of the external anal sphincter, the longitudinal muscle of the rectum was found to extend caudally and divide into two muscle bundles on the oral side of the external anal sphincter. One of these muscle bundles angled dorsally and caudally, forming the conjoined longitudinal muscle, which was found to insert into the intersphincteric space (between the internal and external anal sphincters). The other muscle bundle angled ventrally and caudally, filling the gap between the external anal sphincter and the bulbocavernosus muscle, forming the perineal body. At the level of the superficial transverse perineal muscle, this small muscle bundle headed laterally and intertwined with the longitudinal muscle in the region of the perineal body. At the level of the rectourethralis and deep transverse perineal muscle, the external urethral sphincter was found to occupy an almost completely circular space along the membranous part of the urethra. The dorsal part of the external urethral sphincter was found to be thin at the point of attachment of the rectourethralis muscle, the ventral part of the longitudinal muscle of the rectum. We identified a venous plexus from the NVB located close to the oral and ventral side of the deep transverse perineal muscle. Many vascular branches from the NVB were found to be penetrating the longitudinal muscle and the ventral part of rectourethralis muscle at the level of the apex of the prostate. The rectourethral muscle was wrapped ventrally around the membranous urethra and apex of the prostate. The boundary between the longitudinal muscle and prostate gradually became more distinct, being located at the anterior end of the transabdominal dissection plane. (3) Histological examination showed that the dorsal part of the external urethral sphincter (striated muscle) is thin adjacent to the striated muscle fibers from the deep transverse perineal muscle and the NVB dorsally and close by. The rectourethral muscle was found to fill the space created by the internal anal sphincter, deep transverse perineal muscle, and both levator ani muscles. Many tortuous vessels and tiny nerve fibers from the NVB were identified penetrating the muscle fibers of the deep transverse perineal and rectourethral muscles. The structure of the superficial transverse perineal muscle was typical of striated muscle. These findings were reconstructed three-dimensionally. Conclusions: In intersphincteric resection or abdominoperineal resection for very low rectal cancer, the anterior dissection plane behind Denonvilliers' fascia disappears at the level of the apex of the prostate. The prostate and both NVBs should be used as landmarks during transanal dissection of the non-surgical plane. The rectourethralis muscle should be divided near the rectum side unless tumor involvement is suspected. The superficial and deep transverse perineal muscles, as well as their supplied vessels and nerve fibers from the NVB. In addition, the cutting direction should be adjusted according to the anorectal angle to minimize urethral injury.
Humans ; Male ; Rectum/surgery* ; Anal Canal/anatomy & histology* ; Rectal Neoplasms/surgery* ; Proctectomy ; Urethra/surgery*