Peritoneal disease: key imaging findings that help in the differential diagnosis.

The peritoneum is a unique serosal membrane, which can be the site of primary tumors and, more commonly, secondary pathologic processes. Peritoneal carcinomatosis is the most common malignant condition to affect the peritoneal cavity, and the radiologist plays an important role in making the diagnosis and assessing the extent of disease, especially in sites that may hinder surgery. In this review, we address the role of the radiologist in the setting of peritoneal pathology, focusing on peritoneal carcinomatosis as this is the predominant malignant process, followed by revising typical imaging findings that can guide the differential diagnosis.We review the most frequent primary and secondary peritoneal tumor and tumor-like lesions, proposing a systemic approach based on clinical history and morphological appearance, namely distinguishing predominantly cystic from solid lesions, both solitary and multiple.

Assessment of peritoneal thickness using CT in relation to dialysis adequacy in peritoneal dialysis patients.

Studies assessing peritoneal thickness by CT in peritoneal dialysis (PD) patients are lacking. In this study, we aimed to investigate the association between peritoneal thickness as measured by CT and dialysis adequacy with peritoneal membrane characteristics in PD patients. Ninety-four PD patients were enrolled. Peritoneal thickness was measured by CT. Patients with and without a decrease in Kt/V of at least 0.3 over time were classified as Group 1 and Group 2, respectively. An increase of 0.1 unit of dialysate/plasma (D/P) creatinine over time were considered significant. The relationship between peritoneal membrane thickness, change in Kt/V, and peritoneal membrane characteristics were investigated. There were 31 (33.0%) patients in Group 1. The duration of PD (86.0 ± 64.1 vs. 59.6 ± 45.2 months, p: 0.023), peritoneal thickness (1.02 ± 0.37 vs. 0.87 ± 0.21 mm, p: 0.015), peritoneal calcification (7 [22.6%] vs. 3 [4.8%] patients, p: 0.013], increased D/P creatinine ratio (14 [45.2%] vs. 14 [22.2%] patients, p: 0.031) and CRP (13.9 ± 11.2 vs. 7.1 ± 4.8 mg/L, p: 0.045) were significantly higher in Group 1, whereas albumin (3.6 ± 0.5 vs. 3.8 ± 0.6 g/dL, p: 0.047) and parathyroid hormone (355.2 ± 260.2 vs. 532.1 ± 332.9 ng/L, p: 0.015) levels were significantly lower. Peritoneal thickness was significantly correlated with duration of PD (r: 0.775, p < 0.001) and CRP (r: 0.282, p: 0.006). Regression analysis showed that peritoneal thickness (Exp (B) [95% CI]: 0.029 [0.003-0.253], p: 0.001) was independent predictor of decreased Kt/V in PD patients. In conclusion, prolonged PD duration and increased peritoneal thickness are associated with a decrease in Kt/V over time. CT may be an alternative and noninvasive method instead of peritoneal biopsy for determining the structural changes of the peritoneal membrane .

Evaluation of the distance from the anterior cervicovaginal junction to the anterior peritoneal reflection for anterior colpotomy during vaginal hysterectomy in Korean women.

ABSTRACT: This study aimed to know the distance of the cervicovaginal junction (CVJ) to the anterior peritoneal reflection (APR) as measured in surgical specimens, and assess the distance between the CVJ and APR to ensure safe anterior colpotomy for vaginal hysterectomy among Korean women.Patients who underwent vaginal hysterectomy were included in the analysis. According to the presence of pelvic organ prolapse or menopausal status, the distance from the CVJ to the APR was assessed preoperatively through transvaginal ultrasonography (TV-US), as well as intraoperatively using surgical specimens. The intraclass correlation coefficient was used to determine the reliability between 2 measurements.In total, 171 patients were included. The median distance from the CVJ to the APR measured on TV-US was 19.8 (3.3-41.3) mm. Meanwhile, the median distance from the CVJ to the APR measured using the surgical specimen was 26.0 (12.0-55.0) mm. The intraclass correlation coefficient for the absolute agreement between 2 measurements was 0.353 (95% confidence interval: 0.002-0.570; P < .001), which is indicative of poor reliability. The median distance from the CVJ to the APR measured using the surgical specimen did not differ significantly between the 2 groups according to pelvic organ prolapse (26.0 [12.0-55.0] vs 27.5 [17.0-55.0] mm, P = .076] and menopausal status (27.0 [15.0-55.0] vs 26.0 [12.0-55.0] mm, P = .237).TV-US does not an accurately measure the dissection plane length from the CVJ to the APR during anterior colpotomy. During vaginal hysterectomy, the median distance from the CVJ to the APR measured using the surgical specimen was 26 (12.0-55.0) mm, which can help decrease surgical complications.

Carl Toldt Centennial, Surgeon and Anatomist.

Carl Florian Toldt was an Austrian anatomist who made meaningful contributions worldwide and defined what is one of the most important surgical landmarks in abdominal surgery. Through his research studies, the embryologic dissection plane known as the "White Line of Toldt" represents an important anatomical landmark that helps to mobilize either the ascending or descending colon. His career spanned over 45 years, beginning in Verona and continuing to Prague and Vienna. He was an author of several innovative books and scientific articles regarding micro- and macroscopic anatomy. In addition, he received numerous recognitions and prizes for his work, making him an essential figure in the medical scientific community. Even a street in Vienna, Karl-Toldt-Weg, is named in his honor. The purpose of this historical article is to celebrate and honor Toldt 100 years following his death, remembering his scientific contributions to the medical and surgical fields and giving thanks for his numerous accomplishments. This article brings light to the man behind the eponym.

Anatomical Distance From the Cervicovaginal Junction to the Uterovesical Peritoneal Reflection.

OBJECTIVE: The objective of this study was to measure the anatomical distance from the cervicovaginal junction to the uterovesical peritoneal reflection (CJ-PR). METHODS: A total of 120 hysterectomy patients were selected as study subjects. The uterus was removed, and the CJ-PR distance was immediately measured. For total vaginal hysterectomy, measurement was performed intraoperatively. The cervical length was also measured postoperatively. RESULTS: The median (interquartile) CJ-PR distance for all subjects was 3.3 (2.9-3.7) cm. Comparison of premenopausal and postmenopausal women without prolapse revealed median CJ-PR distances of 3.3 (3.0-3.6) cm and 3.0 (2.6-3.4) cm, respectively. The CJ-PR distance was longer in women with prolapse (4.6 [3.7-5.6] cm) than in those without prolapse (3.2 [2.8-3.6] cm). The median cervical lengths were 3.1 (2.7-3.6) cm for postmenopausal patients without prolapse and 4.4 (3.6-5.8) cm for postmenopausal patients with prolapse. CONCLUSIONS: Knowledge of the CJ-PR distance may help gynecologists predict how far the uterovesical PR is from the anterior vaginal incision.

Structure and surgical dissection layers of the bare area of the liver.

BACKGROUND: The bare area was reportedly formed by direct adhesion between the liver and diaphragm, meaning that the bare area lacked serosal components. This study aimed to analyze the structure of the bare area by an integrated study of surgical and laparoscopic images and pathological studies and describe surgical procedures focusing on the multilayered structure. METHODS: Several surgical specimens of hepatectomy were analyzed histologically to evaluate the macroscopic structure of the bare area. Laparoscopic images and cadaver anatomy of the bare area were also examined. RESULTS: The multilayered structure of the bare area comprised the liver, sub-serosal connective tissue, liver serosa, parietal peritoneum, retroperitoneal connective tissue, epimysium of the diaphragm, and diaphragm, in order from the liver to the diaphragm. The liver serosa and the parietal peritoneum fused with each other. This multilayered structure of the bare area is observed almost constantly. There are two layers in the dissection of the bare area in surgical procedures, an outer layer of the fused peritoneum (near the diaphragm) and an inner layer of the fused peritoneum (near the liver). Laparoscopic images enabled us to recognize the multilayered structure of the bare area. CONCLUSIONS: Histopathological findings showed the bare area to be a multilayered structure. In cases where tumors are located underneath the bare area, it could be important to dissect the bare area, with careful attention to its multilayered structure. Surgical dissection of the bare area in the outer layer of the fused peritoneum could allow a sufficient safety margin.

The Peritoneum: What Nuclear Radiologists Need to Know.

The peritoneum is the largest and most complex serous membrane in the human body. The peritoneal membrane is composed of a layer of mesothelium supported by a thin layer of connective tissue. The peritoneum is one continuous sheet, forming two layers and a potential space between them - the peritoneal cavity- which is subdivided into multiple communicating spaces containing small amount of serous fluid that facilitates frictionless movement of mobile intraabdominal viscera. Peritoneum also contributes to fluid exchange mechanism and plays a role in immune response. The peritoneum is subject to many neoplastic and non-neoplastic processes including infections, trauma, developmental and inflammatory processes. Different Nuclear Medicine imaging techniques can be used to diagnose peritoneal diseases, most of these techniques can be customized depending on the clinical scenario and expected findings. Peritoneal scintigraphy can detect abnormal peritoneal communication or compartmentalization. Several nuclear medicine techniques can help characterize intraperitoneal fluid collections and differentiate sterile from infected fluid. PET imaging plays an important role in imaging of different neoplastic and non-neoplastic peritoneal pathologies. Nuclear radiologists need to be familiar with peritoneal anatomy and pathology to interpret peritoneal findings in dedicated peritoneal nuclear medicine imaging studies, as part of more general nuclear medicine scans, or on CT or MRI component of hybrid imaging studies. The purpose of this article is to review the normal peritoneal anatomy, various pathologic processes involving the peritoneum, and different nuclear medicine and hybrid imaging techniques that can help detect, characterize, and follow up peritoneal pathology.

[Rise and mix of membrane anatomy].

Membrane anatomy is the anatomy of mesentery in broad sense and its beds, which was merged from clinical results of surgical practice, optic observation and traditional theories contradiction or omission. Membrane anatomy is not only a plane, but also a body or bloc which is surrounded by fascia and serous membrane. It is not only fascia, but also a channel or pathway, in which the life event occurred. It is not only mesentery anatomy, but included mesentery beds, on which the mesentery was lied, even buried in. Following the new version of this anatomy map, surgical hazard during operation and postoperative oncological recurrence will be decreased simultaneously. And, following the definition of the mesentery in broad sense, new mesenteries will be discovered under macro surgery, which will optimize surgical operation and get better surgical and oncological results.

[Are various theoretical models of membrane anatomy mutually exclusive or inclusive?]

The theory of membrane anatomy is now widely accepted due to the observation of fine anatomical structure with the help of laparoscopic magnifying effect. From the perspective of systematic anatomy, the mesentery is considered as an integral organ in the theory of mesenteric anatomy. Interfascial anatomy belongs to regional anatomy, which focuses on the guiding significance of fascial space for operation. The theory of membrane anatomy belongs to surgical anatomy or applied anatomy, which emphasizes the anatomy of membrane and mesangial bed, and reveals the existence of 'metastasis V' in the mesentery. It is considered that the essence of membrane anatomy operation is to prevent cancer leakage. Various theories of membrane anatomy seek common ground while reserving differences, complement each other, and upgrade iteratively. They help to explain the structure and function of membrane from different perspectives and they are of great benefit to improve the quality of operations. Thus, they should be treated in an eclectic manner.

[Concept of membrane anatomy in laparoscopic sleeve gastrectomy procedure].

Membrane anatomy refers to the fascia and/or serosa enveloping the organs and their blood vessels and hanging on the posterior wall of the body cavity, which emphasizes the entirety and integrity of the membrane during operation. The concept can also be applied to most surgical operations. This article mainly expounds the application of the concept of membrane anatomy in the process of laparoscopic sleeve gastrectomy, which is embodied in the key steps of separating the greater omentum, mobilizing the fundus, mobilizing the posterior wall of the stomach, cutting the greater curvature of the stomach, reinforcing the staple line of the stomach, and suturing the greater omentum with staple line, in order to make the laparoscopic sleeve gastrectomy more accurate and precise with less bleeding, fewer complications and faster postoperative recovery.

[Total mesorectal excision with preservation of Denonvilliers' fascia (iTME) based on membrane anatomy].

Total mesorectal excision (TME) has been advocated as the golden standard of mid-low rectal cancer surgery for nearly 30 years. However, the complication of postoperative urinary and sexual dysfunctions due to intraoperative nerve injury has yet to be improved. Based on the concept of membrane anatomy, we carried out a systematic study on the important membrane anatomical structure anterior to the rectum--Denonvilliers' fascia. From multiple aspects including anatomy, physiology, histochemistry and surgical practice, we verified the importance of Denonvilliers' fascia for TME surgery in prevention of intraoperative nerve injury and postoperative urogenital dysfunction. Moreover, based on anatomical study of the surgical marker line of Denonvilliers' fascia (Wei's line) and surgical plane, we proved that total mesorectal excision with preservation of Denonvilliers' fascia (iTME) was feasible and practical. Therefore, we conducted a large multicentric randomized controlled trial (RCT). The mid-term result demonstrated that compared with traditional TME surgery, iTME was more effective in reducing the incidence of postoperative urinary and sexual dysfunctions in male patients with mid-low rectal cancer, without sacrifice of short-term tumor radical outcome. We believe that the final RCT result of iTME, based on membrane anatomy, will provide solid evidence for the update of concepts of rectal cancer surgery.

[Better understanding of interfacial planes in colorectal cancer surgery and the value of small vessels on fascia in the identification of interfacial planes].

The introduction of total mesorectal excision and wider use of laparoscopic surgery pushed the field of colorectal surgery into an era of interfasical dissection. The Japanese suggestion of fascial arrangement of the trunk in a multilaminar, symmetrical and parallel way helps in better understanding of fascial relationship and interfascial planes surrounding the colon and the rectum. However, different interpretations of the multilayer retroperitoneal fascial relationship, complexity of fascial structures within the pelvis and dense adhesion between two apposed fasciae at special points make it still challenging for the surgeon to decide on the precise interfascial plane for colorectal mobilization. Small vessels on fasica propria of the rectum and various retroperitoneal fascia, especially ureterohypogastric fascia show distinctive features. The root of small vessels on fascia propria of the rectum helps to identify the anterolateral and posterolateral interfascial plane in the middle and low rectum. The longitudinal trajectory of small vessel on ureterohypogastric fascia and scarcity interfascial vascular communication between mesocolic and retroperitoneal fascia help the surgeon to find and stay in the interfacial plane during colorectal mobilization. More knowledge of fascial and interfascial plane will certainly help achieve better mesocolic mesorectal integrity and reduce the risk of injuries to autonomic nerves. More anatomical, histological and embryological studies are warranted with respect to relationship between small vessels and fasciae.

[Effects of sleeve gastrectomy base on "membrane anatomy" concept on postoperative nausea and vomiting in patients with obesity or metabolic diseases].

Objective: To explore the effects of the application of membrane anatomy concept in sleeve gastrectomy on postoperative nausea and vomiting (PONV) in patients with obesity or metabolic diseases. Methods: A retrospective cohort study was conducted. Clinical data of 88 patients with obesity or metabolic diseases who underwent laparoscopic sleeve gastrectomy in The First Affiliated Hospital of Jinan University from September 2018 to June 2019 were retrospectively analyzed. Forty patients underwent sleeve gastrectomy with membrane anatomy concept as membrane anatomy group, and the other 48 patients underwent traditional sleeve gastrectomy as traditional operation group. There were no significant differences in baseline data between the two groups (all P>0.05). The PONV score of and the times of antiemetic drugs used during 0-6 h and 6-24 h after operation were compared between the two groups. Higher PONV represents more serious nause and vomiting, the score ≥5 is defined as clinical significant PONV. Results: All patients of the two groups successfully completed the operation, and there was no conversion to open, reoperation, and operation-related death. The intraoperative blood loss in the membrane anatomy group was significantly less than that in the traditional surgery group [median: 5.0 (5.0, 5.8) ml vs. 10.0 (5.0, 10.0) ml, Z=-3.265, P=0.001]. There were no significant differences between the two groups in terms of operative time, postoperative hospital stay, gastroesophageal reflux, pain score and postoperative complications (all P>0.05). There was no postoperative bleeding or gastric leakage in either groups. There were no significant differences in PONV score, incidence of clinically significant PONV and use of antiemetics 0-6 h after operation between two groups (all P>0.05). From 6 to 24 hours after operation, compared with traditional surgery group, the membrane anatomy group had lower PONV score (4.6±0.9 vs. 5.1±0.7, t=-2.192, P=0.007), lower incidence of clinically significant PONV [55.0% (22/40) vs. 83.3% (40/48), χ(2)=8.414, P=0.004] and less use of antiemetics [3 times: 10.0% (4/40) vs. 27.1% (13/48), Z=-2.880, P=0.004]. Postoperative follow-up ranged from 1 to 6 months (median 3), 32 cases in membranous anatomy group and 38 cases in the traditional operation group were followed up. One case in the traditional operation group received symptomatic treatment in the local hospital due to functional intestinal obstruction 1 month after surgery and was discharged after recovery. The remaining patients had no postoperative complications and were not readmitted to hospital. Conclusion: Sleeve gastrectomy based on membrane anatomy in the treatment of patients with obesity or metabolic syndrome can make surgical procedure more precise and meticulous, reduce the intraoperative bleeding and the incidence of PONV.

[The key points to comprehend the pelvic fascia].

Pelvic fascia is considered to be one controversial human anatomic structure. According to the characteristics of specialized surgery, colorectal surgeons, gynecologic surgeons and urologic surgeons respectively marked the pelvic fascia, but the naming is not unified. For some specific anatomic structures (such as pelvic plexus), different scholars have different descriptions of their positions. The lack of standard anatomic terms makes it difficult to understand the corresponding anatomic structures, and also hinders the communication between disciplines. Combined with autopsy research, surgical observation and literature review, we discussed the common puzzles of pelvic clinical anatomy. The main points of this article are as follows. (1) Urogenital fascia and vesicohypogastric fascia are the components of visceral fascia. (2) The visceral fascia and fascia propria of rectum are two separate layers. (3) The pelvic plexus is located on the outside of the confluence of visceral fascia and Denonvilliers' fascia. (4) To understand the pelvic lateral ligament from the perspective of layers. (5) To understand pelvic fascia from a holistic perspective.

Mesentery - a 'New' organ.

The mesentery is the organ in which all abdominal digestive organs develop, and which maintains these in systemic continuity in adulthood. Interest in the mesentery was rekindled by advancements of Heald and Hohenberger in colorectal surgery. Conventional descriptions hold there are multiple mesenteries centrally connected to the posterior midline. Recent advances first demonstrated that, distal to the duodenojejunal flexure, the mesentery is a continuous collection of tissues. This observation explained how the small and large intestines are centrally connected, and the anatomy of the associated peritoneal landscape. In turn it prompted recategorisation of the mesentery as an organ. Subsequent work demonstrated the mesentery remains continuous throughout development, and that abdominal digestive organs (i.e. liver, spleen, intestine and pancreas) develop either on, or in it. This relationship is retained into adulthood when abdominal digestive organs are directly connected to the mesentery (i.e. they are 'mesenteric' in embryological origin and anatomical position). Recognition of mesenteric continuity identified the mesenteric model of abdominal anatomy according to which all abdominal abdomino-pelvic organs are organised into either a mesenteric or a non-mesenteric domain. This model explains the positional anatomy of all abdominal digestive organs, and associated vasculature. Moreover, it explains the peritoneal landscape and enables differentiation of peritoneum from the mesentery. Increased scientific focus on the mesentery has identified multiple vital or specialised functions. These vary across time and in anatomical location. The following review demonstrates how recent advances related to the mesentery are re-orientating the study of human biology in general and, by extension, clinical practice.

Albumin-based cancer therapeutics for intraperitoneal drug delivery: a review.

Albumin is a remarkable carrier protein with multiple cellular receptor and ligand binding sites, which are able to bind and transport numerous endogenous and exogenous compounds. The development of albumin-bound drugs is gaining increased importance in the targeted delivery of cancer therapy. Intraperitoneal (IP) drug delivery represents an attractive strategy for the local treatment of peritoneal metastasis (PM). PM is characterized by the presence of widespread metastatic tumor nodules on the peritoneum, mostly originating from gastro-intestinal or gynaecological cancers. Albumin as a carrier for chemotherapy holds considerable promise for IP delivery in patients with PM. Data from recent (pre)clinical trials suggest that IP albumin-bound chemotherapy may result in superior efficacy in the treatment of PM compared to standard chemotherapy formulations. Here, we review the evidence on albumin-bound chemotherapy with a focus on IP administration and its efficacy in PM.

Peritoneal spaces: measurements of peritoneal surfaces / Espacios peritoneales: mediciones de las superficies peritoneales

In this work the quantitative data of the surfaces that limit the sub-spaces that constitute the peritoneal space are shown. The methodology of measurement of the two sheets (parietal and visceral) of the peritoneal serosa applied in our previous paper (Albanese et al., 2009), in non-eviscerated corpses, allowed us to know for the first time, the surface or total extension of the peritoneum "in situ". This methodology was useful to determine the surface or area of the two sheets of the peritoneum, which limit the peritoneal space. Our objective in this study was to determine the total peritoneal areas (visceral + parietal) in human corpses that are not eviscerated, which limit the different sub-spaces that make up the peritoneal space. Ten female cadavers fixed in 5 % formaldehyde solution were used. Small cellophane films were placed directly on the peritoneal sheets. The digital images were obtained by scanning these models. The surface was determined by the "Scion image for Windows" program. The results were expressed as mean +/- SE. The analysis of variance (ANOVA) was used for the statistical study. The results obtained showed that the peritoneal sub-space of greater surface area was retro-omental (mean +/- SE 7767.81 +/- 646.70 cm2 p <0.01 ANOVA), due to the large extension of its visceral surface ( mean +/- SE 7401.82 +/- 640.99 cm2). More than 50 % of the surface of the entire peritoneum corresponds to said sub-space. The smallest peritoneal sub-space (3 % of the total peritoneal surface) was the pelvic sub-space (mean +/- SE 431.30 +/- 41.62 cm2). We believe that this information may be useful in case of peritoneal pathological processes or those affected by prolonged peritoneal dialysis, and that knowledge of the surface and extension of the peritoneal space involved may contribute to the estimation of the peritoneal surface involved and help to plan the treatment.

En este trabajo se muestran los datos cuantitativos de las superficies que limitan el espacio peritoneal y los sub-espacios que lo componen. La metodología de medición de las dos hojas (parietal y visceral) de la serosa peritoneal empleada en cadáveres no eviscerados, permitió conocer por primera vez, la superficie o extensión total del peritoneo in situ. El objetivo en este trabajo fue determinar -en cadáveres humanos no evisceradoslas áreas peritoneales totales (visceral + parietal) que limitan los distintos sub-espacios que conforman el espacio peritoneal. Se han utilizado diez cadáveres femeninos no eviscerados fijados en solución de formaldehido al 5 %. Pequeñas películas de celofán se colocaron directamente sobre las hojas peritoneales. La obtención de imágenes digitales se realizó escaneando estos modelos. La superficie fue determinada por el programa "Scion image for Windows". Los resultados se expresaron como media +/- SE. Para el estudio estadístico se utilizó el análisis de varianza (ANOVA). Los resultados obtenidos demostraron que el sub-espacio peritoneal de mayor superficie fue el retro-omental (media +/- SE 7767,81 +/ - 646,70 cm2 p<0.01 ANOVA), debido a la gran extensión de su superficie visceral (media +/- SE 7401,82 +/- 640,99 cm2). Más del 50 % de la superficie de todo el peritoneo corresponde a dicho sub-espacio. El sub-espacio peritoneal más pequeño (3 % de la superficie peritoneal total) fue el sub-espacio pélvico (media +/SE 431,30 +/- 41,62 cm2). Esta información podrá ser de utilidad en el caso de procesos patológicos peritoneales o áreas afectadas por diálisis peritoneal prolongada. De esta manera el conocimiento de la extensión del espacio peritoneal involucrado, puede contribuir a la estimación de la magnitud y gravedad de la superficie peritoneal comprometida. Además puede ayudar a planificar el tratamiento.