Investigation of Changes in Saliva in Radiotherapy-Induced Head Neck Cancer Patients

Radiation-associated changes in saliva composition of head and neck cancer patients: A systematic review

Xerostomia is a common radiation-associated toxicity in patients with head and neck cancer. Although several studies examined the decrease in saliva production due to radiotherapy (RT) and investigated the factors associated with this side effect, little is known about the change in radiation-associated saliva composition. This systematic review is the first to summarize existing data and give an overview of the change in pH/buffer capacity, electrolytes, proteins, enzymes, and mucins due to radiation to the salivary glands. Literature search was performed in PubMed and Embase with 47 articles finally eligible for the review, analyzing the saliva composition at several time points before, during and/or after RT, or comparing findings in irradiated patients to a healthy control group. Overall, RT leads to a substantial decrease in salivary pH and buffer capacity. For sodium, chloride and calcium ion, as well as amylase, an increased concentration or activity during RT was reported in most of the studies, followed by a subsequent decrease either already during RT or after the end of treatment. Different trends have been described for the total protein concentration during and after RT. Lactoferrin, however, increased considerably, especially in the first phase of RT. Mucin 5B (MUC5B) concentrations showed a slight increase during RT and concentrations around baseline values again six months post-radiotherapy.

Treatment outcomes in maxillofacial rehabilitation: a scoping review protocol

OBJECTIVE

The objective of this scoping review is to assess the treatment outcomes following maxillofacial rehabilitation and to identify the tools used to evaluate those outcomes.

INTRODUCTION

Maxillofacial defects caused due to tumor, trauma, or any pathology affects the patient physically, mentally, and psychologically. Various methodologies and strategies are used for jaw reconstruction and oral rehabilitation to help the patient regain the functions and quality of life that were lost due to the defect. The evaluation of these treatment outcomes is imperative to assess the success of rehabilitation.

INCLUSION CRITERIA

The review will include patients with any maxillofacial defect caused by a developmental anomaly, trauma, or tumor. The patients must have undergone any type of reconstruction and/or rehabilitation and can be from any age group. All treatment outcomes of maxillofacial rehabilitation will be considered. Information from primary and secondary sources and from diverse geographical settings will be included.

METHODS

This review will follow the JBI methodology for scoping reviews. Databases to be searched will include PubMed (Ovid), Scopus, PsycINFO (EBSCOhost), CINAHL(EBSCO), Web of Science, Cochrane CENTRAL, ProQuest Dissertations and Theses, and Google Scholar (first 10 pages of the search). Two independent reviewers will screen the titles and abstracts and extract data from selected studies. Data will be presented in tabular format, accompanied by a narrative summary.

DETAILS OF THE REVIEW CAN BE FOUND IN OPEN SCIENCE FRAMEWORK

https://doi.org/10.17605/OSF.IO/DP8WC.

Chronic Phenotypes Underlying Radiation-Induced Salivary Gland Dysfunction

Head and neck cancer (HNC) is the sixth most diagnosed cancer, and treatment typically consists of surgical removal of the tumor followed by ionizing radiation (IR). While excellent at controlling tumor growth, IR often damages salivary glands due to their proximity to common tumor sites. Radiation damage to salivary glands results in loss of secretory function, causing severe and chronic reductions in salivary flow. This leads to the patient-reported sensation of dry mouth, termed xerostomia, which significantly reduces quality of life for HNC patients and survivors. The mechanisms underlying salivary gland damage remain elusive, and therefore, treatment options are scarce. Available therapies provide temporary symptom relief, but there is no standard of care for permanent restoration of function. There is a significant gap in understanding the chronic mechanistic responses to radiation as well as treatments that can be given in the months to years following cessation of treatment. HNC cases are steadily rising; particularly, the number of young patients diagnosed with nonfatal human papillomavirus + HNC continues to increase. The growing number of HNC diagnoses and improved prognoses results in more people living with xerostomia, which highlights the mounting need for restorative treatments. Mechanisms underlying chronic damage include decreases in acinar differentiation markers, increases in acinar cell proliferation, immune and inflammatory dysregulation, and metabolic changes including increases in amino acids and reductions in glycolysis and oxidative phosphorylation, fibrosis, and dysregulated neuronal responses. Currently, promising treatment options include adenoviral gene transfers and stem cell therapy. Thus, this review describes in depth known mechanisms contributing to chronic damage and discusses therapeutic advances in treating chronically damaged glands. Understanding the chronic response to radiation offers potential in development of new therapeutics to reverse salivary gland damage and improve the quality of life of HNC survivors.

Investigation of Hydrocolloid Plant Polysaccharides as Potential Candidates to Mimic the Functions of MUC5B in Saliva

The successful substitution of complex physiological fluids, such as human saliva, remains a major challenge in drug development. Although there are a large number of saliva substitutes on the market, their efficacy is often inadequate due to short residence time in the mouth, unpleasant mouthfeel, or insufficient protection of the teeth. Therefore, systems need to be identified that mimic the functions of saliva, in particular the salivary mucin MUC5B and the unique physiological properties of saliva. To this end, plant extracts known to contain hydrocolloid polysaccharides and to have mucus-forming properties were studied to evaluate their suitability as saliva substitutes. The aqueous plant extracts of Calendula officinalis, Fucus sp. thalli, and lichenan from Lichen islandicus were examined for composition using a range of techniques, including GC-MS, NMR, SEC, assessment of pH, osmolality, buffering capacity, viscoelasticity, viscoelastic interactions with human saliva, hydrocolloid network formation, and in vitro cell adhesion. For this purpose, a physiologically adapted adhesive test was developed using human buccal epithelial cells. The results show that lichenan is the most promising candidate to mimic the properties of MUC5B. By adjusting the pH, osmolality, and buffering capacity with K2HPO4, it was shown that lichenan exhibited high cell adhesion, with a maximum detachment force that was comparable to that of unstimulated whole mouth saliva.

Characteristics of Tongue Pressure Measured by Novel Multisite Flexible Sensors in Nasopharyngeal Carcinoma Patients With Dysphagia

OBJECTIVE

To explore characteristics of tongue pressure changes in nasopharyngeal carcinoma (NPC) patients with dysphagia after radiotherapy using a novel system with multisite flexible sensors.

DESIGN

Prospective observational study.

SETTING

Inpatient rehabilitation centers and community dwellings.

PARTICIPANTS

Nineteen patients with dysphagia after radiotherapy for NPC and 19 healthy participants were recruited for this study (N=38).

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

A new 9-site (3 × 3) flexible tongue pressure sensor was used to measure tongue-to-palate pressure across different parts of the tongue. The oral tongue was divided into 3 parts: anterior tongue region (TAR), central tongue region (TCR), and posterior tongue region (TPR); 3 sensors were placed on each part. The mean tongue pressure and endurance time at the 3 sites in the TAR, TCR, and TPR were analyzed. The ratios of the mean TAR, TCR, and TPR values were calculated.

RESULTS

Pressures of TAR, TCR, and TPR in NPC patients with dysphagia were significantly lower than those in healthy participants (P<.05). The pressure in TPR decreased most significantly, followed by that in TCR. The endurance times of TAR and TCR were longer than those of healthy participants (P<.05). The endurance time of TPR was not significantly different between the patients and healthy participants (P>.05). Ratios of pressure between TAR and TCR and TAR and TPR in patients were lower than that in healthy participants (P<.05). There was no significant difference in the TCR to TPR pressure ratio between patients and healthy participants (P>.05).

CONCLUSIONS

Tongue pressure significantly decreased in NPC patients with dysphagia, and the drop in pressure was most pronounced in the TPR area. The results of our study indicate that we should pay attention to the pressure training of the TPR during treatments. The endurance time of the TAR and TCR increased significantly, which may be due to bolus transport compensation. Therefore, clinical rehabilitation strategies should aim to increase the endurance time training in NPC patients after radiotherapy to help increase the effectiveness of the swallowing process in patients.

Copper chelation reduces early collagen deposition and preserves saliva secretion in irradiated salivary glands

Radiation therapy is a first-line treatment for head and neck cancer; however, it typically leads to hyposalivation stemming from fibrosis of the salivary gland. Current strategies to restore glandular function are dependent on the presence of residual functional salivary gland tissue, a condition commonly not met in patients with extensive fibrotic coverage of the salivary gland resulting from radiation therapy. Fibrosis is defined by the pathological accumulation of connective tissue (i.e., extracellular matrix) and excessive deposition of crosslinked (fibrillar) collagen that can impact a range of tissues and given that collagen crosslinking is necessary for fibrosis formation, inhibiting this process is a reasonable focus for developing anti-fibrotic therapies. Collagen crosslinking is catalyzed by the lysyl oxidase family of secreted copper-dependent metalloenzymes, and since that copper is an essential cofactor in all lysyl oxidase family members, we tested whether localized delivery of a copper chelator into the submandibular gland of irradiated mice could suppress collagen deposition and preserve the structure and function of this organ. Our results demonstrate that transdermal injection of tetrathiomolybdate into salivary glands significantly reduced the early deposition of fibrillar collagen in irradiated mice and preserved the integrity and function of submandibular gland epithelial tissue. Together, these studies identify copper metabolism as a novel therapeutic target to control radiation induced damage to the salivary gland and the current findings further indicate the therapeutic potential of repurposing clinically approved copper chelators as neoadjuvant treatments for radiation therapy.

The Impact of Commercially Available Dry Mouth Products on the Corrosion Resistance of Common Dental Alloys

Dental implants are thought to be implanted for life, but throughout their lifespan, they function in aggressive oral environment, resulting in corrosion of the material itself as well as possible inflammation of adjacent tissues. Therefore, materials and oral products for people with metallic intraoral appliances must be chosen carefully. The purpose of this study was to investigate the corrosion behavior of common titanium and cobalt-chromium alloys in interaction with various dry mouth products using electrochemical impedance spectroscopy (EIS). The study showed that different dry mouth products lead to different open circuit potentials, corrosion voltages, and currents. The corrosion potentials of Ti64 and CoCr ranged from -0.3 to 0 V and -0.67 to 0.7 V, respectively. In contrast to titanium, pitting corrosion was observed for the cobalt-chromium alloy, leading to the release of Co and Cr ions. Based on the results, it can be argued that the commercially available dry mouth remedies are more favorable for dental alloys in terms of corrosion compared to Fusayama Meyer's artificial saliva. Thus, to prevent undesirable interactions, the individual characteristics of not only the composition of each patient's tooth and jaw structure, but also the materials already used in their oral cavity and oral hygiene products, must be taken into account.

Biochemical analysis of saliva in head and neck cancer patients receiving definitive chemoradiotherapy

BACKGROUND

Radiation therapy leads to salivary gland damage that causes xerostomia, the standard radiation-induced complication during radiotherapy that affects the quality of life in head and neck cancer patients. This study was conducted at a tertiary cancer institute in Punjab state to analyze the influence of radiation therapy on various parameters and substances of saliva.

MATERIALS AND METHODS

Sixty head and neck cancer patients who underwent conventional radiotherapy on a Cobalt machine were included. Saliva was collected in both stimulated and unstimulated states. Stimulated whole saliva was collected by applying two to three drops of citric acid solution (2%) over the dorsum of the tongue bilaterally at 30-s intervals for 2 min. Biochemical changes in the whole saliva were evaluated by biochemical methods at baseline, completion of therapy, and 3 and 6 months post-radiotherapy completion.

RESULTS

The lowest concentration of proteins was seen after the therapy in unstimulated and stimulated saliva. Salivary protein levels showed a rising trend toward baseline in 3- and 6-month posttherapy samples. The peak value (0.4 mg/dl) was reached in the stimulated saliva after therapy. Salivary amylase did not show a consistent concentration graph. The salivary concentrations of sodium, potassium, and chloride showed peak values after radiotherapy. The lowest salivary pH was obtained at completion of therapy, both in unstimulated and stimulated saliva. After 3 months of chemoradiotherapy, the saliva reached a pH value of 8.3, whereas 6-month posttherapy sample showed a pH value of 8.4 in both unstimulated and stimulated saliva.

CONCLUSIONS

At the completion of chemoradiotherapy, the total salivary protein, albumin, and inorganic components (calcium, magnesium, phosphorus) showed a downward trend from the baseline values due to the damage caused to the acinar part of the salivary gland by radiotherapy. The rise in salivary electrolytes' concentrations is attributed to the fact that even though there is loss of absorptive property of the tubular portion of the salivary gland, it retains its secretory property. Saliva becomes thick, scarce, tenacious, and acidic during the period of chemoradiotherapy.

The application of salvage surgery improves the quality of life and overall survival of extensively recurrent head and neck cancer after multiple operation plus radiotherapy

OBJECTIVES

The prognosis, choice of reconstruction and the quality of life (QOL) after salvage surgery (SS) for extensively locoregional recurrent/metastatic head and neck cancer (R/M HNC) is an important issue, but there are few reports at present.

MATERIALS AND METHODS

We analyzed extensively locoregional R/M HNC patients from March 1, 2015, to December 31, 2021 who underwent SS with latissimus dorsi or pectoralis major musculocutaneous flaps. QOL were accessed using QLQ-H&N35 and UW-QOL questionnaire. Wilcoxon signed-rank test was used to compare difference between pre- and post-QOL and Kaplan-Meier curves were used in estimate overall survival (OS) and disease-free survival (DFS). The literature review summarized recent 10 years clinical trials of nonoperative treatment in R/M head and neck cancer.

RESULTS

1362 patients were identified and 25 patients were analyzed after screened. Median age at surgery was 59 years (range 43-77), 15/25(60%) were male and 22/25(88%) chose latissimus dorsi flap. Better mean pain score after applying massive soft tissue flaps revealed relief of severe pain(p<0.001) which strongly associated with improvement of QOL. The improved mean overall QOL score after surgery revealed a better QOL(p<0.001). As of June 1, 2022, 11/25 (44%) of the patients were alive. The 1-year, 2-year OS after SS was 58.4% and 37.2%, while the 1-year, 2-year DFS was 26.2% and 20.9%. The median OS of our study was better than nonoperative treatment of 11 included clinical trials.

CONCLUSIONS

R/M HNC patients underwent SS can obtain survival benefit. The application of massive soft tissue flap in SS could significantly enhance the QOL for patients with extensively locoregional R/M HNC, especially by relieving severe pain.

Minimization of Adverse Effects Associated with Dental Alloys

Metal alloys are one of the most popular materials used in current dental practice. In the oral cavity, metal structures are exposed to various mechanical and chemical factors. Consequently, metal ions are released into the oral fluid, which may negatively affect the surrounding tissues and even internal organs. Adverse effects associated with metallic oral appliances may have various local and systemic manifestations, such as mouth burning, potentially malignant oral lesions, and local or systemic hypersensitivity. However, clear diagnostic criteria and treatment guidelines for adverse effects associated with dental alloys have not been developed yet. The present comprehensive literature review aims (1) to summarize the current information related to possible side effects of metallic oral appliances; (2) to analyze the risk factors aggravating the negative effects of dental alloys; and (3) to develop recommendations for diagnosis, management, and prevention of pathological conditions associated with metallic oral appliances.

Oral Candida spp. Colonisation Is a Risk Factor for Severe Oral Mucositis in Patients Undergoing Radiotherapy for Head & Neck Cancer: Results from a Multidisciplinary Mono-Institutional Prospective Observational Study

Simple Summary

This study aims to find a correlation between Candida spp. oral colonisation prior to radiotherapy and (i) the development of severe oral mucositis (OM) (grade 3/4) and (ii) early development of severe OM (EOM). Candida spp. in the oral cavity appears to be a predictive factor of EOM. Preventive treatment could aid in reducing incidence of EOM. Further clinical trials are required to confirm our findings.

Abstract

Background: This study aims to find a correlation between Candida spp. oral colonisation prior to radiotherapy (RT) and (i) the development of severe oral mucositis (OM) (grade 3/4) and (ii) early development of severe OM (EOM). Methods: The protocol was registered on ClinicalTrials.gov (ID: NCT04009161) and approved by the ethical committee of the ‘Fondazione Policlinico Universitario Gemelli IRCCS’ (22858/18). An oral swab was obtained before RT to assess the presence of Candida spp. Severe OM occurring before a dose of 40 Gy was defined as EOM. Results: No patient developed G4 OM, and only 36/152 patients (23.7%) developed G3 OM. Tumour site and lymphocytopenia were risk factors for severe OM (OR for tumour site: 1.29, 95% CI: 1–1.67, p = 0.05; OR for lymphocytopenia: 8.2, 95% CI: 1.2–55.8, p = 0.03). We found a correlation between Candida spp. and EOM (OR: 5.13; 95% CI: 1.23–21.4 p = 0.04). Patients with oral colonisation of Candida spp. developed severe OM at a mean dose of 38.3 Gy (range: 28–58; SD: 7.6), while negative patients did so at a mean dose of 45.6 Gy (range: 30–66; SD: 11.1). Conclusions: Candida spp. in the oral cavity appears to be a predictive factor of EOM.

Diagnosis, Prevention, and Treatment of Radiotherapy-Induced Xerostomia: A Review

In patients with head and neck cancer, irradiation (IR)-sensitive salivary gland (SG) tissue is highly prone to damage during radiotherapy (RT). This leads to SG hypofunction and xerostomia. Xerostomia is defined as the subjective complaint of dry mouth, which can cause other symptoms and adversely affect the quality of life. In recent years, diagnostic techniques have constantly improved with the emergence of more reliable and valid questionnaires as well as more accurate equipment for saliva flow rate measurement and imaging methods. Preventive measures such as the antioxidant MitoTEMPO, botulinum toxin (BoNT), and growth factors have been successfully applied in animal experiments, resulting in positive outcomes. Interventions, such as the new delivery methods of pilocarpine, edible saliva substitutes, acupuncture and electrical stimulation, gene transfer, and stem cell transplantation, have shown potential to alleviate or restore xerostomia in patients. The review summarizes the existing and new diagnostic methods for xerostomia, along with current and potential strategies for reducing IR-induced damage to SG function. We also aim to provide guidance on the advantages and disadvantages of the diagnostic methods. Additionally, most prevention and treatment methods remain in the stage of animal experiments, suggesting a need for further clinical research, among which we believe that antioxidants, gene transfer, and stem cell transplantation have broad prospects.

The Effect of Nano-chitosan and Nano-curcumin on Radiated Parotid Glands of Albino Rats: Comparative Study

Decreasing the salivary flow rate manifested by xerostomia occurs early during the irradiation treatment. The duration of depressed salivary function varies among patients. Various histopathological changes occur in the salivary glands. The current study was performed to investigate and compare between the possible anti-radiotherapeutic effect of the gamma rays-synthesized curcumin nanoparticles (Cur NPs), and chitosan nanoparticles (Cs NPs). They were utilized to overcome the histopathological changes associated with radiation therapy in albino rats’ parotid glands. Sixty adult male Albino rats were utilized, fifteen as control group, fifteen as radiated group and thirty as Cur NPs and Cs NPs treatment groups. The parotid glands were dissected and examined histologically, immunohistochemically for vascular endothelial growth factor (VEGF) as well as histo-morphometrically. The histological results proved the antiradio-therapeutic effect of Cur NPs, and Cs NPs, with the least degenerative changes in the Cur NPs treated group. A high significant increase in VEGF was recorded in the radiated group as compared to the other treated groups. Cs NPs have proved to be an anti-radiotherapeutic and anti-oxidant substrate in treating the histopathological changes in radiated parotid glands of albino rats. However, it was lagging behind Cur NPs in all analyses but non-significant differences between them have been recorded.

Graphical Abstract

Salivary Gland Function, Development and Regeneration

Salivary glands produce and secrete saliva, which is essential for maintaining oral health and overall health. Understanding both the unique structure and physiological function of salivary glands, as well as how they are affected by disease and injury will direct the development of therapy to repair and regenerate them. Significant recent advances, particularly in the OMICS field, increase our understanding of how salivary glands develop at the cellular, molecular and genetic levels; the signaling pathways involved, the dynamics of progenitor cell lineages in development, homeostasis and regeneration and the role of the extracellular matrix microenvironment. These provide a template for cell and gene therapies as well as bioengineering approaches to repair or regenerate salivary function.

Phytochemical-rich vegetable and fruit juice alleviates oral mucositis during concurrent chemoradiotherapy in patients with locally advanced head and neck cancer

Background

Objective

Methods

Results

Conclusion

Section

Taxonomy

•

The blended vegetable and fruit juice (VFJ) was rich in total polyphenols and carotenoids.

•

In head and neck cancer patients, the VFJ was significantly associated with a lower risk of chemoradiotherapy-induced ulcerative oral mucositis.

•

VFJ is healthy, safe, and effective dietary strategy against oral mucositis.

Stimulated saliva composition in patients with cancer of the head and neck region

BACKGROUND

To analyse over time changes in stimulated whole saliva regarding total protein, Immunoglobulin A (IgA), and mucin type O-glycans (mostly MUC5B and MUC7) in head and neck cancer patients.

METHODS

29 dentate patients (20 men and 9 women, 59 ± 8 years) treated with curative radiation therapy and chemotherapy for cancer of the head and neck region were included. The stimulated whole salivary secretion rate was determined and saliva collected at four time-points: at pretreatment, and at 6 months, 1 and 2 years post treatment. The total protein concentration was determined spectrophotometrically by using Bicinchoninic Acid assay and Immunoglobulin A (IgA) by using ELISA technique. Glycosylation pattern of salivary mucins was determined in samples collected pre- and post treatment by using LC/MS electrospray and mucin content quantified using SDS-AgPAGE gels and PAS staining.

RESULTS

Compared with pretreatment, the total protein concentration was increased already at 6 months post treatment (p < 0.01), and continued to increase up to 2 years post treatment (p < 0.001). During that period no significant changes in IgA concentration was detected. At pretreatment, the output/min of both total protein and IgA was significantly higher than at all time-points post treatment. Saliva from the cancer patients showed a low abundance/no detectable MUC7, while the MUC5B level remained, compared to saliva from a healthy control. The glycomic analysis showed that the percentage of core 2 O-glycans was increased as core 1, 3 and 4 O-glycans were decreased. The level of sialylation was higher at 6 months post treatment, while sulfation was lower.

CONCLUSION

A decreased output per minute of proteins at decreased salivary secretion rate, as well as reduced sulfation of MUC5B at 6 months post treatment tended to correlate with the patients' experience of sticky saliva and oral dryness. At 2 years post treatment, the decreased amount of IgA combined with a lowered salivary secretion rate indicate a reduced oral defense with increased risk of oral infections.

Cytokine-Mediated Inflammation in the Oral Cavity and Its Effect on Lipid Nanocarriers

Topical drug administration to the oral mucosa proves to be a promising treatment alternative for inflammatory diseases. However, disease-related changes in the cell barrier must be considered when developing such delivery systems. This study aimed at investigating the changes in the lining mucosa caused by inflammation and evaluating the consequences on drug delivery systems such as nanostructured lipid carriers (NLC). For this, TR146 cells were treated with inflammatory cytokines and bacterial components. Cell viability and integrity, reactive oxygen species (ROS), and interleukin (IL)-8 release were used as endpoints to assess inflammation. Translocation of phosphatidylserine, cytoskeletal arrangement, opening of desmosomes, and cell proliferation were examined. Transport studies with NLC were performed considering active and passive pathways. The results showed that IL-1ß and tumor necrosis factor α induced inflammation by increasing IL-8 and ROS production (22-fold and 2-fold). Morphologically, loss of cell–cell connections and formation of stress fibers and hyperplasia were observed. The charge of the cell membrane shifted from neutral to negative, which increased the absorption of NLC due to the repulsive interactions between the hydrophobic negative particles and the cell membrane on the one hand, and interactions with lipophilic membrane proteins such as caveolin on the other.

Focus on the Primary Prevention of Intrauterine Adhesions: Current Concept and Vision

Intrauterine adhesion (IUA), and its severe form Asherman syndrome (Asherman’s syndrome), is a mysterious disease, often accompanied with severe clinical problems contributing to a significant impairment of reproductive function, such as menstrual disturbance (amenorrhea), infertility or recurrent pregnancy loss. Among these, its correlated infertility may be one of the most challenging problems. Although there are many etiologies for the development of IUA, uterine instrumentation is the main cause of IUA. Additionally, more complicated intrauterine surgeries can be performed by advanced technology, further increasing the risk of IUA. Strategies attempting to minimize the risk and reducing its severity are urgently needed. The current review will expand the level of our knowledge required to face the troublesome disease of IUA. It is separated into six sections, addressing the introduction of the normal cyclic endometrial repairing process and its abruption causing the formation of IUA; the etiology and prevalence of IUA; the diagnosis of IUA; the classification of IUA; the pathophysiology of IUA; and the primary prevention of IUA, including (1) delicate surgical techniques, such as the use of surgical instruments, energy systems, and pre-hysteroscopic management, (2) barrier methods, such as gels, intrauterine devices, intrauterine balloons, as well as membrane structures containing hyaluronate–carboxymethylcellulose or polyethylene oxide–sodium carboxymethylcellulose as anti-adhesive barrier.