Light-Operated Transient Unilateral Adhesive Hydrogel for Comprehensive Prevention of Postoperative Adhesions.

Dislocation of anti-adhesion materials, non-specific tissue adhesion, and the induction of secondary fibrinolysis disorders are the main challenges faced by postoperative anti-adhesion materials. Herein, a self-leveling transient unilateral adhesive hydrogel is custom-designed to conquer these challenges with a theoretically calculated and dual-step tailored gellan gum (GG) as the sole agent. First, the maximum gelation temperature of GG is lowered from 42-25 °C through controlled perturbation of intra- and inter-molecular hydrogen bonds, which is achieved by employing the methacrylic anhydride as a "hydrogen bond's perturbator" to form methacrylate GG (MeGG). Second, the "self-leveling" injectability and wound shape adaptably are endowed by the formation of borate-diol complexed MeGG (BMeGG). Finally, the transient unilateral tissue-adhesive hydrogel (BMeGG-H) barrier is prepared through photo-controlled cross-linking of reactive alkenyl groups. This degradable hydrogel demonstrates favorable rheological properties, light-controlled unilateral adhesion properties, biocompatibility, anti-fibrin adhesion, and anti-cell adhesion properties in vitro. Comprehensive regulation of the fibrinolysis balance toward non-adhesion is conformed in a rat model after intra-abdominal surgery via anti-autoinflammatory response, intestinal wall integrity repair, and Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) balance adjustment. Notably, the 14th day anti-adhesion effective rate is 100%, indicating its significant potential in clinical applications for postoperative anti-adhesion.

Neutrophil Extracellular Traps-Inhibiting and Fouling-Resistant Polysulfoxides Potently Prevent Postoperative Adhesion, Tumor Recurrence, and Metastasis.

Peritoneal metastasis (PM) is considered one of the most dreaded forms of cancer metastases for both patients and physicians. Aggressive cytoreductive surgery (CRS) is the primary treatment for peritoneal metastasis. Unfortunately, this intensive treatment frequently causes clinical complications, such as postoperative recurrence, metastasis, and adhesion formation. Emerging evidence suggests that neutrophil extracellular traps (NETs) released by inflammatory neutrophils contribute to these complications. Effective NET-targeting strategies thus show considerable potential in counteracting these complications but remain challenging. Here, one type of sulfoxide-containing homopolymer, PMeSEA, with potent fouling-resistant and NET-inhibiting capabilities, is synthesized and screened. Hydrating sulfoxide groups endow PMeSEA with superior nonfouling ability, significantly inhibiting protein/cell adhesion. Besides, the polysulfoxides can be selectively oxidized by ClO- which is required to stabilize the NETs rather than H2O2, and ClO- scavenging effectively inhibits NETs formation without disturbing redox homeostasis in tumor cells and quiescent neutrophils. As a result, PMeSEA potently prevents postoperative adhesions, significantly suppresses peritoneal metastasis, and shows synergetic antitumor activity with chemotherapeutic 5-Fluorouracil. Moreover, coupling CRS with PMeSEA potently inhibits CRS-induced tumor metastatic relapse and postoperative adhesions. Notably, PMeSEA exhibits low in vivo acute and subacute toxicities, implying significant potential for clinical postoperative adjuvant treatment.

Super-Structured Wet-Adhesive Hydrogel with Ultralow Swelling, Ultrahigh Burst Pressure Tolerance, and Anti-Postoperative Adhesion Properties for Tissue Adhesion.

Wet-adhesive hydrogels have been developed as an attractive strategy for tissue repair. However, achieving simultaneously low swelling and high burst pressure tolerance of wet-adhesive hydrogels is crucial for in vivo application which remains challenges. Herein, a novel super-structured porous hydrogel (denoted as PVA/PAAc-N+ ) is designed via facile moisture-induced phase separation-solvent exchange process for obtaining porous polyvinyl alcohol (PVA) hydrogel as dissipative layer and in situ photocuring technology for entangling quaternary ammonium-functionalized poly(acrylic acid)-based wet-adhesive layer (PAAc-N+ ) with the porous surface of PVA layer. Benefitting from the ionic crosslinking between quaternary ammonium ions and carboxylate ions in PAAc-N+ wet-adhesive layer as well as the high crystallinity induced by abundant hydrogen bonds of PVA layer, the hydrogel has unique ultralow swelling property (0.29) without sacrificing adhesion strength (63.1 kPa). The porous structure of PVA facilitates the mechanical interlock at the interface between PAAc-N+ wet-adhesive layer and tough PVA dissipative layer, leading to the ultrahigh burst pressure tolerance up to 493 mm Hg and effective repair for porcine heart rupture; the PVA layer surface of PVA/PAAc-N+ hydrogel can prevent postoperative adhesion. By integrating ultralow swelling, ultrahigh burst pressure tolerance, and anti-postoperative adhesion properties, PVA/PAAc-N+ hydrogel shows an appealing application prospect for tissue repair.

Injectable Asymmetric Adhesive-Antifouling Bifunctional Hydrogel for Peritoneal Adhesion Prevention.

Peritoneal adhesion is a common problem after abdominal surgery and can lead to various medical problems. In response to the lack of in situ retention and pro-wound healing properties of existing anti-adhesion barriers, this work reports an injectable adhesive-antifouling bifunctional hydrogel (AAB-hydrogel). This AAB-hydrogel can be constructed by "two-step" injection. The tissue adhesive hydrogel based on gallic acid-modified chitosan and aldehyde-modified dextran is prepared as the bottom hydrogel (B-hydrogel) by Schiff base reaction. The aldehyde-modified zwitterionic dextran/carboxymethyl chitosan-based hydrogel is formed on the B-hydrogel surface as the antifouling top hydrogel (T-hydrogel). The AAB-hydrogel exhibits good bilayer binding and asymmetric properties, including tissue adhesive, antifouling, and antimicrobial properties. To evaluate the anti-adhesion effect in vivo, the prepared hydrogels are injected onto the wound surface of a mouse abdominal wall abrasion-cecum defect model. Results suggest that the AAB-hydrogel has antioxidant capacity and can reduce the postoperative inflammatory response by modulating the macrophage phenotype. Moreover, the AAB-hydrogel could effectively inhibit the formation of postoperative adhesions by reducing protein deposition, and resisting fibroblast adhesions and bacteria attacking. Therefore, AAB-hydrogel is a promising candidate for the prevention of postoperative peritoneal adhesions.

Efficacy of Naldemedine on Intestinal Hypomotility and Adhesions in Rodent Models of Postoperative Ileus.

Postoperative ileus (POI) often decreases patients' QOL because of prolonged hospitalization and readmission. Alvimopan, a peripheral µ-opioid receptor antagonist, is currently the only therapeutic drug for POI. The aim of this study was to examine the efficacy of naldemedine (a peripheral µ-opioid receptor antagonist with a non-competitive pharmacological profile different from that of alvimopan) on postoperative intestinal hypomotility and adhesion in rodent models, and compare it with the effects of alvimopan. Oral administration of naldemedine (0.3 mg/kg) and alvimopan (3 mg/kg) significantly inhibited the decrease in intestinal motility induced by mechanical irritation in mice (p < 0.01, for both). Naldemedine (1 mg/kg) significantly shortened the adhesion length in chemical-induced postoperative adhesion model rats (p < 0.05). Alvimopan (3 mg/kg) also significantly reduced the adhesion ratio (p < 0.01). These findings suggest that naldemedine is effective for postoperative intestinal hypomotility and adhesions in rodents (i.e., as for alvimopan). Thus, naldemedine may be a useful option for the treatment of POI.

A Zwitterionic Hydrogel with Anti-Oxidative and Anti-Inflammatory Properties for the Prevention of Peritoneal Adhesion by Inhibiting Mesothelial-Mesenchymal Transition.

Postoperative peritoneal adhesion is a serious clinical complication. Various hydrogel barriers have been developed to prevent peritoneal adhesion. However, it remains a challenge to design a hydrogel with desirable physicochemical properties and bioactivities. In this study, a zwitterionic polysaccharide-based multifunctional hydrogel is developed using epigallocatechin-3-gallate (EGCG) to prevent postoperative abdominal adhesion. This hydrogel is simple to use and has desirable properties, such as excellent injectability, self-healing, and non-swelling properties. The hydrogel also has ultralow fouling capabilities, such as superior bactericidal performance, cell and protein adhesion, and low immunogenicity resistance. Moreover, the hydrogel exhibits good antioxidant activity, which is attributed to the integration of EGCG. Furthermore, the detailed mechanism from in vivo and in vitro experimental studies illustrates that hydrogel compositions can synergistically prevent adhesion formation through multiple pathways, including anti-inflammatory and antioxidant capabilities and inhibition effects on the mesothelial-mesenchymal transition (MMT) process induced by transforming growth factor (TGF-ß). In summary, this zwitterionic multifunctional hydrogel has great potential to prevent postoperative adhesion formation in the clinical setting.

An Adhesive/Anti-Adhesive Janus Tissue Patch for Efficient Closure of Bleeding Tissue with Inhibited Postoperative Adhesion.

Most of the current bioadhesives cannot perform well on bleeding tissues while postoperative adhesion is a general but serious clinical issue. Here, a three-layer biodegradable Janus tissue patch (J-TP) that is able to simultaneously enable efficient closure of bleeding wounds with significantly promoted clotting ability and suppressed postoperative adhesion of tissues is reported. A dry adhesive hydrogel bottom layer of the J-TP can form rapid (within 15 s) and strong (tensile strength up to 98 kPa) adhesion to bleeding/wet tissues with high bursting pressure (about 312.5 mmHg on a sealed porcine skin) through hydrogen binding and covalent conjugation between the carboxyl & N-hydroxy succinimide (NHS) groups of hydrogel and the primary amine groups of tissues, while the phosphonic motifs can significantly reduce blood loss (by 81% on a rat bleeding liver model) of bleeding wounds. A thin polylactic acid (PLA) middle layer can improve the tensile strength (by 132%) of the J-TP in wet conditions while the grafted zwitterionic polymers can effectively prevent postoperative tissue adhesion and inflammatory reaction. This J-TP may be a promising tissue patch to assist the clinical treatment of injured bleeding tissues with inhibited postoperative adhesion.

Research on Mechanisms of Chinese Medicines in Prevention and Treatment of Postoperative Adhesion.

Postoperative adhesion (PA) is currently one of the most unpleasant complications following surgical procedures. Researchers have developed several new strategies to alleviate the formation of PA to a great extent, but so far, no single measure or treatment can meet the expectations and requirements of clinical patients needing complete PA prevention. Chinese medicine (CM) has been widely used for thousands of years based on its remarkable efficacy and indispensable advantages CM treatments are gradually being accepted by modern medicine. Therefore, this review summarizes the formating process of PA and the efficacy and action mechanism of CM treatments, including their pharmacological effects, therapeutic mechanisms and advantages in PA prevention. We aim to improve the understanding of clinicians and researchers on CM prevention in the development of PA and promote the in-depth development and industrialization process of related drugs.

An Integrally Formed Janus Hydrogel for Robust Wet-Tissue Adhesive and Anti-Postoperative Adhesion.

Facile fabrication of asymmetrically adhesive hydrogel with robust wet tissue adhesion simultaneously with effective anti-postoperative adhesion still remains a great challenge. In this work, an integrally formed Janus hydrogel is facilely fabricated in one step by controlling the interfacial distribution of free carboxyl groups on the two sides of hydrogels. At a lower stirring speed, the generated bigger sized emulsion droplets mainly occupy the top surface of hydrogel, which effectively hinders the exposition of carboxyl groups on the top surface, driving them to be more distributed on the bottom surface, ultimately resulting in the poor adhesion of top surface but robust adhesion of bottom surface to various wet tissue even underwater. The difference in adhesive strength achieves as high as 20 times between the two surfaces. In vivo rabbit experiment outcomes clearly validate that the bottom surface of hydrogel firmly adheres to the stomach defect, and the other opposite surface can efficiently address the postoperative adhesion problem. Besides, this hydrogel exhibits superior mechanical toughness and conductivity which has been used as a highly adhesive strain sensor to real-time monitor the beating heart in vivo. This simple yet effective strategy provides a much more feasible approach for creating Janus hydrogels bioadhesives.

An Overview of Postoperative Intraabdominal Adhesions and Their Role on Female Infertility: A Narrative Review.

Postoperative intraabdominal adhesions can occur after more than 90% of gynecologic surgeries. They not only cause chronic pelvic pain and small bowel obstruction, but are also one of the main reasons for infertility. Adhesions are not only a burden for the affected patients, but are also a burden for the healthcare system, since the treatment of adhesion-associated complications costs a considerable amount of money. The gold standard for the diagnosis of adhesions is by laparoscopy, although other methods, such as transvaginal hydro-laparoscopy, are being discussed as better alternatives. Ideally, adhesions are avoided inherently, by operating carefully and by using microsurgical principles. If this is not possible, gel barriers have been shown to be successful in reducing postoperative adhesions.

Piperine liposome-embedded in hyaluronan hydrogel as an effective platform for prevention of postoperative peritoneal adhesion.

This study aimed to prepare piperine (PIP) loaded liposomes in hyaluronic acid (HA) hydrogel to provide a hybrid superstructure for postoperative adhesion prevention. Liposomes were prepared using thin-film hydration method. The optimised formulation was characterised by size, SEM, TEM, FTIR, encapsulation efficiency (EE)% (w/w), and release pattern. Liposome-in-hydrogel formulation was investigated by rheology, SEM, and release studies. The efficacy was evaluated in a rat peritoneal abrasion model. EE% (w/w) increased with increasing lipid concentration from 10 to 30; however, a higher percentage of Chol reduced EE% (w/w). The optimised liposome (EE: 68.10 ± 1.71% (w/w), average diameter: 513 ± 8 nm, PDI: 0.15 ± 0.04) was used for hydrogel embedding. No sign of adhesion in 5/8 rats and no collagen deposition confirmed the in vivo effectiveness of the optimised formulation. Overall, providing a sustained delivery of PIP, the developed liposome-in-hydrogel formulation can be a promising carrier to prevent postoperative adhesion.

Application of Polymer Hydrogels in the Prevention of Postoperative Adhesion: A Review.

Postoperative adhesion is a common post-surgery complication formed between the surface of the body cavity, ranging from a layer of connective tissue to a fibrous bridge containing blood vessels and nerve tissue. Despite achieving a lot of progress, the mechanisms of adhesion formation still need to be further studied. In addition, few current treatments are consistently effective in the prevention of postoperative adhesion. Hydrogel is a kind of water-expanding crosslinked hydrophilic polymer network generated by a simple reaction of one or more monomers. Due to the porous structure, hydrogels can load different drugs and control the drug release kinetics. Evidence from existing studies has confirmed the feasibility and superiority of using hydrogels to counter postoperative adhesions, primarily due to their outstanding antifouling ability. In this review, the current research status of hydrogels as anti-adhesion barriers is summarized, the character of hydrogels in the prevention of postoperative adhesion is briefly introduced, and future research directions are discussed.

pH-responsive nanocomposite hydrogel for simultaneous prevention of postoperative adhesion and tumor recurrence.

Abdominal adhesion and tumor recurrence are two thorny problems in the postoperative treatment of abdominal tumors. Although important progress has been made in the application of hydrogels in adjuvant therapy after tumor surgery, most of the products can not effectively combine the prevention of abdominal adhesion and the removal of residual cancer cells. In this study, a nanocomposite hydrogel (Col-APG-Cys@HHD) was prepared by crosslinking collagen and recombinant albumin nanoparticles (HHD NPs) with aldehydeylated polyethylene glycol (APG6K) followed by immobilizing zwitterionic cysteine (Cys) to one surface. One surface of the hydrogel adhered to the postoperative wound due to the adhesive properties of collagen, while the other surface coated with cysteine formed a hydration layer to hinder the stick of proteins and cells, thereby reducing the adhesion between tissues. Additionally, Col-APG-Cys@HHD hydrogel disintegrated under acidic condition and released HHD NPs that targeted into cancer cells and released drugs in response to low pH environment. The in vivo experiments' results demonstrated that Col-APG-Cys@HHD hydrogel could prevent intraperitoneal adhesions and inhibit tumor growth with minimal side effects, providing a potential strategy for the hydrogel-based drug delivery system in postoperative adjuvant therapy of tumors. STATEMENT OF SIGNIFICANCE: Tissue adhesion and tumor recurrence usually occur after abdominal tumor surgery. Hydrogels have been widely studied in adjuvant treatment of abdominal tumors, but their synergy in terms of controllable drug release and anti-peritoneal adhesion still needs to be improved. Herein, a nanocomposite hydrogel (Col-APG-Cys@HHD) was designed and constructed with one side that was tissue adhesive and the other side as antifouling. Additionally, the Col-APG-Cys@HHD hydrogel showed controlled drug release behavior in response to a pH gradient (6.5 to 5.5). This was conducive to its dissociation in an acidic tumor environment followed by the release of nanoparticles that entered into tumor cells and delivered docetaxel . To sum up, the Col-APG-Cys@HHD hydrogel demonstrated synergistic therapy for prevention of abdominal adhesion and tumor recurrence after abdominal tumor surgery.

A sandwiched patch toward leakage-free and anti-postoperative tissue adhesion sealing of intestinal injuries.

Ideal repair of intestinal injury requires a combination of leakage-free sealing and postoperative antiadhesion. However, neither conventional hand-sewn closures nor existing bioglues/patches can achieve such a combination. To this end, we develop a sandwiched patch composed of an inner adhesive and an outer antiadhesive layer that are topologically linked together through a reinforced interlayer. The inner adhesive layer tightly and instantly adheres to the wound sites via -NHS chemistry; the outer antiadhesive layer can inhibit cell and protein fouling based on the zwitterion structure; and the interlayer enhances the bulk resilience of the patch under excessive deformation. This complementary trilayer patch (TLP) possesses a unique combination of instant wet adhesion, high mechanical strength, and biological inertness. Both rat and pig models demonstrate that the sandwiched TLP can effectively seal intestinal injuries and inhibit undesired postoperative tissue adhesion. The study provides valuable insight into the design of multifunctional bioadhesives to enhance the treatment efficacy of intestinal injuries.

The effect of natural surfactants on the development of postoperative intraabdominal adhesion.

Background/aim: The development of postoperative adhesion after abdominal surgery is sometimes a severe problem. Our study investigates the effectiveness of exogenous surfactant application in preventing adhesion development in the experimental adhesion model. Materials and methods: This randomized-controlled interventional study was carried out in the animal laboratory of Kahramanmaras Sütçü Imam University between March 1 and March 31, 2020. An experimental intra-abdominal adhesion model was established in 24 adult female rats by cecal abrasion. Rats were randomly divided into four groups. Groups I, II, and III were taken intraperitoneally as beractant, poractant, and calfactant applied groups, respectively. Group IV was the control group. Relaparotomy was performed in all groups on the 15th postoperative day, and intra-abdominal adhesions were scored macroscopically according to the Canbaz scoring system. In addition, the cecal regions were evaluated microscopically and scored according to the Zühlke microscopic classification system. The scores of the groups were compared statistically. Results: The Zühlke adhesion development score was significantly lower in the exogenous surfactant applied groups. In addition, when the surfactant-applied groups were compared among themselves, it was seen that the adhesion score in the beractant group was significantly better than the other surfactant types (p < 0.01). Conclusion: Our study results showed that prophylactic intraperitoneal surfactant application significantly reduced postoperative adhesion development, particularly beractant.

What is the impact of intraperitoneal surfactant administration against postoperative intraabdominal adhesion formation? an experimental study.

Background/Aim: Surfactant is a surface-active substance that, in addition to its detergent effect, also has effects that reduce inflammation and fibrosis. Because of these effects, it was aimed herein to investigate the effect of intraperitoneal surfactant application on preventing postoperative peritoneal adhesion formation in a uterine horn adhesion model. Materials and methods: Twenty-one Wistar albino rats were randomly divided into 3 groups (G1-G3), as follows: G1 (n = 7): control group. The abdomen was opened and then closed; G2 (n = 7): adhesion group. The abdomen was opened. Then, a 2-cm linear incision was made over the right uterine horn, 2 mL of isotonic saline was administered intraperitoneally, and the abdomen was closed; and G3 (n = 7): treatment group. The abdomen was opened, a 2-cm linear incision was made over the right uterine horn, 2 mL (70 mg/kg) of surfactant was administered intraperitoneally, and the abdomen was closed. After 15 days, the rats were euthanized, the abdomens were reopened, and adhesion scoring was performed. After the right uterine horns were removed and fixed with 10% formalin, appropriate sections were taken from the traumatized tissue, stained with Masson's trichrome, and fibrosis and inflammation scoring were performed. Results: The adhesion area and intensity were significantly higher in G2 than in G1 and G3 (p = 0.001) and were similar in G1 and G3 (p = 0.165). While fibrosis and inflammation were significantly higher in G2 than in G1 and G3 (p = 0.001), there was no difference between G1 and G3 (p = 0.5). Conclusion: Intraperitoneal surfactant administration at a dose of 70 mg/kg was found to be effective in preventing intraabdominal adhesion formation in a rat uterine horn model.

Research on Mechanisms of Chinese Medicines in Prevention and Treatment of Postoperative Adhesion / 中国结合医学杂志

Postoperative adhesion (PA) is currently one of the most unpleasant complications following surgical procedures. Researchers have developed several new strategies to alleviate the formation of PA to a great extent, but so far, no single measure or treatment can meet the expectations and requirements of clinical patients needing complete PA prevention. Chinese medicine (CM) has been widely used for thousands of years based on its remarkable efficacy and indispensable advantages CM treatments are gradually being accepted by modern medicine. Therefore, this review summarizes the formating process of PA and the efficacy and action mechanism of CM treatments, including their pharmacological effects, therapeutic mechanisms and advantages in PA prevention. We aim to improve the understanding of clinicians and researchers on CM prevention in the development of PA and promote the in-depth development and industrialization process of related drugs.

Biocompatible Nanocomposites for Postoperative Adhesion: A State-of-the-Art Review.

To reduce and prevent postsurgical adhesions, a variety of scientific approaches have been suggested and applied. This includes the use of advanced therapies like tissue-engineered (TE) biomaterials and scaffolds. Currently, biocompatible antiadhesive constructs play a pivotal role in managing postoperative adhesions and several biopolymer-based products, namely hyaluronic acid (HA) and polyethylene glycol (PEG), are available on the market in different forms (e.g., sprays, hydrogels). TE polymeric constructs are usually associated with critical limitations like poor biocompatibility and mechanical properties. Hence, biocompatible nanocomposites have emerged as an advanced therapy for postoperative adhesion treatment, with hydrogels and electrospun nanofibers among the most utilized antiadhesive nanocomposites for in vitro and in vivo experiments. Recent studies have revealed that nanocomposites can be engineered to generate smart three-dimensional (3D) scaffolds that can respond to different stimuli, such as pH changes. Additionally, nanocomposites can act as multifunctional materials for the prevention of adhesions and bacterial infections, as well as tissue healing acceleration. Still, more research is needed to reveal the clinical potential of nanocomposite constructs and the possible success of nanocomposite-based products in the biomedical market.

Liquid-Liquid Phase-Separated Hydrogel with Tunable Sol-Gel Transition Behavior as a Hotmelt-Adhesive Postoperative Barrier.

Postoperative barriers have been widely used to prevent adhesions. However, there are currently few barriers that satisfy clinical requirements, such as tissue adhesion, operability, and biocompatibility. Inspired by the adhesion system of living organisms, we report a liquid-liquid phase-separated hydrogel as a single-syringe hotmelt-type postoperative barrier. Mixing polyethylene glycol with gelatin formed liquid-liquid phase-separated hydrogels through segregative liquid-liquid phase separation. Incorporation of a liquid-liquid phase-separated system into gelatin can enhance the sol-gel transition temperature to give a hotmelt-adhesive property to hydrogels. Hotmelt-adhesive hydrogels became a sol phase and cohered into tissue gaps when warmed and solidified at body temperature to adhere to soft tissues. The hydrogels exhibited tissue adhesion to large intestine tissues and showed improved mechanical strength, gelation time, and shear-thinning properties. In rat cecum-abdominal adhesion models, it was confirmed that the resulting hydrogels prevented abdominal adhesion and did not prevent tissue regeneration. Hotmelt-adhesive hydrogels with high tissue adhesive properties, operability, and biocompatibility have enormous potential as barriers to prevent postoperative complications.

Collagen Type-I Agent Reduced Postoperative Bowel Adhesions Following Laparoscopic and Robot-Assisted Radical Prostatectomy: A Prospective, Single-Blind Randomized Clinical Trial.

This study aimed to compare the anti-adhesive effect of collagen type-I (COL) agent and hyaluronic acid-carboxymethylcellulose (HA/CMC) following laparoscopic and robotic radical prostatectomies. This study was a randomized, controlled, single-blind, multicenter study using COL and HA/CMC in patients who underwent laparoscopic and robotic radical prostatectomies. All patients were randomly assigned to either the COL (n = 66) or HA/CMC (n = 65) group. Viscera slide ultrasound sonography was recorded on the day of surgery (V2) and 12 weeks later (V4). The primary end point was the difference in the excursion distance in the viscera slide ultrasonography between V2 and V4. A total of 131 patients participated in this study. The viscera slide distance in the test and control groups was 1.89 ± 0.49 cm and 1.80 ± 0.45 cm, respectively, at V2 (p = 0.275). The average distance of the viscera slide in the test and control group was 1.59 ± 0.49 cm and 1.64 ± 0.45 cm, respectively at V4 (p = 0.614). None of the patients showed significant adverse effects. This randomized study showed that the efficacy and stability of the gel-type COL anti-adhesion agent are not inferior to those of HA/CMC, of which the properties are established.