Preoperative leuprolide acetate combined with Interceed optimally reduces uterine adhesions and fibrosis in a rabbit model,

Multifunctional Supramolecular Hydrogel for Prevention of Epidural Adhesion after Laminectomy

Postoperative epidural adhesion remains a clinically challenging problem in spine surgery. Currently there are no effective and safe antifibrotic and antiadhesion biomaterials that have been specifically developed for this complication in clinical practice. Herein we designed and engineered an advanced antiadhesion hydrogel with multiple functionalities, including temperature-responsive gelation, self-healing, tissue adhesiveness, antioxidation, anti-inflammation, and antifibrosis. This multifunctional supramolecular hydrogel can be facilely constructed by integrating three functional modules, i.e., a thermosensitive triblock copolymer, poloxamer 407 (PX); a reactive oxygen species-eliminating and anti-inflammatory nanoparticle (TPCD NP); and an adhesion-enhancing compound, tannic acid (TA). The optimal formulation (PXNT) was hierarchically screened based on in vitro properties and in vivo activities. Therapeutically, local treatment with PXNT hydrogel effectively prevented epidural fibrosis and adhesion after laminectomy in both rats and rabbits. Of note, PXNT hydrogel showed more beneficial efficacy than different control thermosensitive hydrogels and a commercially available barrier product, Interceed. Mechanistically, PXNT hydrogel significantly attenuated local oxidative stress, inhibited inflammatory responses, and reduced fibrotic tissue formation. Moreover, treatment with PXNT hydrogel did not cause systemic adverse effects and neurological symptoms. Consequently, PXNT hydrogel is a highly promising biomaterial for preventing postlaminectomy epidural adhesion and adhesions after other surgeries.

PLGA/PLCA casting and PLGA/PDPA electrospinning bilayer film for prevention of postoperative adhesion

Postoperative adhesion is a common complication and preventing adhesions during or immediately after operation is particularly important. The application of solid barrier materials represents the most successful clinical strategy to prevent postoperative adhesion. However, a simple physical barrier effect might be insufficient in preventing adhesion satisfactorily. Multilayered structures can be designed with an outer layer as the barrier and an inner layer to respond to relative drug release. In this article, bilayer film composed of a PLGA/PLCA casting layer as barrier and PLGA/PDPA electrospinning layer to respond to the release of anti-fibrosis drug l-Phe was designed and synthesized. The adhesion prevention effect of the above PLGA/PLCA/PDPA bilayer film was examined and compared with single PLGA/PLCA casting film and single PLGA/PDPA electrospinning film by applying rabbit sidewall defect-cecum abrasion model. As demonstrated by histological observation and immunohistochemical analysis, the bilayer film was the most effective of the three films in postoperative adhesion prevention in terms of both physical barrier effect and anti-fibrosis effect of the PDPA macromolecular prodrug. Besides anti-fibrosis effect, PDPA could also suppress excess proliferation of vascular endothelial cells and microvessel caused by long-term stimulation of implantation materials to the surrounding tissues. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2030-2039, 2019.

Oxidized, Regenerated Cellulose Adhesion Barrier Plus Intrauterine Device Prevents Recurrence After Adhesiolysis for Moderate to Severe Intrauterine Adhesions

STUDY OBJECTIVE

To compare the efficacy of an oxidized, regenerated cellulose adhesion barrier (Interceed; Ethicon, Somerville, NJ) combined with an intrauterine device (IUD) versus an IUD alone for preventing adhesion recurrence following hysteroscopic adhesiolysis for moderate to severe intrauterine adhesions (IUAs).

DESIGN

Retrospective case series (Canadian Task Force classification III).

SETTING

Tertiary care teaching hospital.

PATIENTS

Patients undergoing treatment for moderate to severe IUAs. The severity of IUA was determined based on the American Fertility Society scoring system (mild, moderate, or severe).

INTERVENTIONS

All cases of hysteroscopic adhesiolysis were reviewed.

MEASUREMENTS AND RESULTS

Seventy-six women with moderate to severe IUAs treated between March 2009 and August 2015 were included. After hysteroscopic adhesiolysis, 35 patients were treated with an IUD alone (group 1), and 41 patients were treated with Interceed plus an IUD (group 2). A second hysteroscopy was performed in all cases three months after the initial hysteroscopy and both groups achieved significant reduction in adhesion scores and grade, especially in group 2 (scores, p < .001; grade, p = .039). Compared with group 1, menstruation dysfunction, pregnancy rate, and live birth rate in group 2 improved with no statistical difference (menstruation improvement, p = .764; pregnancy rate, p = .310; live birth rate, p = .068). However, an adhesion-free uterine cavity was regained significantly owing to the fewer operations in group 2 compared with group 1 (median, 3 vs 4; p = .001). The interval from initial hysteroscopy to conception was significantly shorter in group 2 (median, 12 months vs 51 months; p < .001).

CONCLUSIONS

For moderate to severe IUAs, Interceed combined with an IUD may be an alternative approach for reducing adhesion recurrence after hysteroscopic adhesiolysis.

Interceed and Estrogen Reduce Uterine Adhesions and Fibrosis and Improve Endometrial Receptivity in a Rabbit Model of Intrauterine Adhesions

Intrauterine adhesions (IUA) remain a major cause of infertility. Interceed, a regenerated cellulose adhesion barrier, is used to prevent adhesions in abdominal cavity. This study aimed to determine whether Interceed could reduce adhesions and tissue fibrosis and improve endometrial receptivity (ER) in rabbit. Rabbits were randomized into 6 groups: sham operation, Interceed control, IUA model, Interceed therapy, estrogen therapy, and combination therapy. Four rabbits per group were euthanized to evaluate adhesion severity on the day before intervention and day 7, 14, and 28 after intervention. Number of endometrial glands and degree of endometrial fibrosis acted as markers for adhesion severity. Pseudopregnancy was induced in the remainder, and 8 rabbits per group were killed for assessing ER on days 6, 7, and 8 of pseudopregnancy by ανβ3 integrin and pinopode. We found that Interceed or estrogen therapy led to significant improvement in the adhesion severity on day 28 after intervention, respectively, compared to IUA model group (all P < .05). However, after combination therapy, such improvement achieved comparable to sham operation group as early as day 14 after intervention (glands, P = .711, fibrosis, P = .154). Among the IUA models treated, ER was highest after combination therapy on day 7 of pseudopregnancy, similar to sham operation group (integrin, P = .352, pinopode, P = .154). In conclusion, Interceed and estrogen reduce adhesions and tissue fibrosis and improve ER in a rabbit model and may be novel therapeutic approaches for infertility resulting from IUA.

Evaluation of the effects of gonadotropin-releasing hormone antagonist (GnRH-ant) and agonist (GnRH-a) in the prevention of postoperative adhesion formation in a rat model with immunohistochemical analysis

OBJECTIVE

To investigate the effects of GnRH antagonist (GnRH-ant) and agonist (GnRH-a) in the prevention of postoperative pelvic adhesions by a visual scoring system and immunohistochemical methods in a rat uterine horn model.

DESIGN

Controlled experimental animal study.

SETTING

Animal laboratory at an academic research environment.

ANIMAL(S)

Twenty-one Wistar albino rats.

INTERVENTION(S)

Rats were randomized into three groups. One week before the operation the rats received either GnRH-ant or GnRH-a or saline solution; they then underwent surgical laparotomy, and both uterine horns were traumatized by a scalpel. Three weeks later, all rats were sacrificed and extension and severity of the adhesions in each group were scored by a visual scoring system. Adhesion tissues were evaluated immunohistochemically for vitronectin and u-PAR.

MAIN OUTCOME MEASURE(S)

Scores of extend and severity of adhesions and staining of vitronectin and u-PAR.

RESULT(S)

The extent of adhesion scores were 1.85 ± 0.86, 0.78 ± 1.05, and 0.42 ± 0.64, and the severity of adhesion scores were 1.71 ± 0.91, 0.57 ± 0.85, 0.50 ± 0.75 for control, GnRH-ant, and GnRH-a groups, respectively. The extent and severity of adhesions were significantly lower in both GnRH-ant and GnRH-a groups when compared with the control group. Adhesion extent scores in the GnRH-a group were lower than in the GnRH-ant group, but this difference was not significant. vitronectin and u-PAR staining were significantly greater in both the GnRH-ant and GnRH-a groups than in the control group.

CONCLUSION(S)

GnRH-ant as well as GnRH-a reduced postoperative adhesion formation in a rat model. This finding was supported immunohistochemically by vitronectin and u-PAR staining.

Assessment of the efficacy of absorbable adhesion barriers on dissection in esophagus operations

OBJECTIVE

During childhood, recent repeated operations for esophagus are normally conducted if long gap esophageal atresia exists. During multistaged extrathoracic esophageal elongation procedure, the dissection of the esophagus poses severe problems due to adhesion. However, Gore-Tex membrane may simplify esophagus dissection. The most popular adhesion barriers used today are sodium hyaluronate (Seprafilm; Genzyme Corp., Cambridge, MA) and oxidized regenerated cellulose (Interceed; Johnson&Johnson Medical Inc., New Brunswick, NJ). The purpose of this study is to investigate the efficacy of adhesion barriers on esophagus dissection.

METHODS

In the study, 21 Wistar albino adult male rats were worked on. The rats were randomly divided into three groups, each including seven rats. About 1cm-segment of the esophagus, located just behind the trachea, was dissected from the surrounding tissues through blunt dissection. Rats in group 1 were wrapped with Seprafilm, and in group 2 with Interceed. But the rats in group 3 underwent only esophagus dissection. Three weeks later, during esophagus dissection, adhesion scoring was performed and esophagus was divided into two parts: one for the assessment of hydroxyproline level, and the other for histological examination.

RESULTS

When the adhesion scores of the three groups were compared, there was not a significant difference between the groups (p=0.75). In terms of tissue hydroxyproline levels, mean scores of hydroxyproline revealed no significant difference between the three groups (p=0.19). When the histopathological results were examined, esophagus looked normal and no connective tissues were seen around esophagus.

CONCLUSION

Seprafilm and Interceed had no effect on esophagus dissection. Although Seprafilm had the best mean score, this was statistically insignificant. Gore-Tex might play a better role than Interceed in preventing adhesion formation; however, it is still not certain whether adhesion barrier should be used in such organs as esophagus having no serosa.

Laparoscopic myomectomy for symptomatic uterine myomas

OBJECTIVE

To evaluate the safety, efficacy, and techniques of laparoscopic myomectomy as treatment for symptomatic uterine myomas.

DESIGN

Medline literature review and cross-reference of published data.

RESULTS

Results from randomized trials and clinical series have shown that laparoscopic myomectomy provides the advantages of shorter hospitalization, faster recovery, fewer adhesions, and less blood loss than abdominal myomectomy when performed by skilled surgeons. Improvements in surgical instruments and techniques allows for safe removal and multilayer myometrial repair of multiple large intramural myomas. Randomized trials support the use of absorbable adhesion barriers to reduce adhesions, but there is no apparent benefit of presurgical use of GnRH agonists. Pregnancy outcomes have been good, and the risk of uterine rupture is very low when the myometrium is repaired appropriately.

CONCLUSION(S)

Advances in surgical instruments and techniques are expanding the role of laparoscopic myomectomy in well-selected individuals. Meticulous repair of the myometrium is essential for women considering pregnancy after laparoscopic myomectomy to minimize the risk of uterine rupture. Laparoscopic myomectomy is an appropriate alternative to abdominal myomectomy, hysterectomy, and uterine artery embolization for some women.