A blinded randomized controlled trial evaluating the efficacy of chitosan gel on ostial stenosis following endoscopic sinus surgery

Chitogel with deferiprone following endoscopic sinus surgery: improved wound healing and microbiome

Background

Adhesion formation, sinus ostial narrowing, and presence of pathogenic bacteria are associated with poor outcomes following endoscopic sinus surgery (ESS) for chronic rhinosinusitis. Chitogel has been shown to improve wound healing, restore a healthier microbiome, and reduce post-operative infections post ESS. Deferiprone has antibacterial properties and has been shown to reduce adhesion formation. The aim of the study was to assess whether the addition of low concentration deferiprone to Chitogel further improves surgical outcomes following ESS compared with Chitogel alone.

Methods

In this double-blinded trial, 45 patients undergoing ESS were prospectively recruited. At the end of the surgery, patients were randomised to receive Chitogel alone, Chitogel with 1 mM of deferiprone, or Chitogel with 5 mM of deferiprone to one side of the sinuses (allowing the other side to serve as control). Patients underwent routine follow-ups with symptom questionnaires and nasoendoscopies performed at 2, 6, and 12 weeks post-operatively. Sinus ostial measurements, microbiology, and microbiome swabs from bilateral middle meatuses were collected intraoperatively and at 12 weeks post-operatively.

Results

A significant improvement in the endoscopic appearance of the sinuses and frontal ostial patency was noted at 12 weeks post-operatively (p < 0.05) in all three treatment groups compared with the control. There was no significant difference noted between patients who received Chitogel alone and those who received Chitogel with 1 or 5 mM deferiprone.

Conclusion

Chitogel alone, Chitogel with 1 mM deferiprone, and Chitogel with 5 mM deferiprone used following ESS led to a significant improvement in endoscopic appearance of the sinuses and frontal ostial preservation at 12 weeks post-operatively. No significant difference was found with the addition of deferiprone to Chitogel.

[Fundamentals and practice of the application of nasal packing in sinonasal surgery]

BACKGROUND AND OBJECTIVES

This paper presents an overview on nasal packing materials which are available in Germany. The current literature is analyzed whether there are robust criteria regarding use nasal packing after sinonasal surgery, whether there are fundamental and proven advantages or disadvantages of products, and what this means in clinical practice.

MATERIALS AND METHODS

Selective literature analysis using the PubMed database (key words "nasal packing", "nasal tamponade", "nasal surgery", "sinonasal surgery", or "sinus surgery"), corresponding text books and resulting secondary literature.

RESULTS AND CONCLUSIONS

Because of systematic methodological shortcomings, the literature does not help in the decision-making about which nasal packing should be used after which kind of sinonasal surgery. In fact, individual approaches for the many different clinical scenarios are recommended. In principle, nasal packing aims in hemostasis, should promote wound healing, and should not result in secondary morbidity. Nasal packing materials should be smooth (non-absorbable materials), inert (absorbable materials), and should not exert excessive pressure. Using non-absorbable packing entails the risk of potentially lethal aspiration and ingestion. For safety reasons inpatient control is recommended as long as this packing is in situ. With other, uncritical packing materials and in patients with special conditions, outpatient control could be justified.

Ostial Patency Measurements After Endoscopic Sphenoidotomies and Frontal Sinusotomies

BACKGROUND

Sphenoid and frontal sinuses have narrow ostia and are prone to stenosis. However, their relative rates of patency are not well established, and descriptive rates of sphenoid stenosis have never been reported. The objective is to measure the patency of the sphenoid and frontal sinus ostia postoperatively.

METHODS

A prospective multi-institutional cohort study was performed. Ostial patency was measured at surgery and 3 and 6 months postoperatively. Pertinent clinical history such as the presence of nasal polyps and prior history of ESS as well as the use of steroid eluting stents were recorded. Overall stenosis rates were calculated for both the sphenoid and frontal sinuses, and Wilcoxon-Signed Rank Test was used to compare intraoperative and postoperative ostial areas. Factorial Analysis of Variance (ANOVA) was performed to determine effects of 5 clinical factors.

RESULTS

Fifty patients were included. The mean sphenoid sinus ostial area decreased 42.2% in size from baseline to 3 months postoperatively (T0 55.2 ± 28.7 mm vs T3 m 31.8 ± 25.5 mm, P < .001). The mean frontal sinus ostial area decreased 39.8% in size from baseline to 3 months postoperatively (T0 33.7 ± 17.2 mm vs T3 m 19.9 ± 15.1 mm, P < .001). Neither the sphenoid nor the frontal sinus ostial patency demonstrated statistically significant change from 3 to 6 months postoperatively.

CONCLUSION

Both sphenoid and frontal sinus ostia routinely narrow postoperatively, predominately from baseline to 3 months. These findings can serve as a reference for both clinical outcomes and future studies of these surgeries.

Outcomes of Frontal Sinus Stenting With Steroid Impregnated Microsponge Versus Steroid-Eluting Implant

BACKGROUND

Mometasone-eluting poly-L-lactide-coglycolide (MPLG) is available commercially for frontal sinus ostium (FSO) stenting. An alternative chitosan polymer-based drug delivery microsponge is also available at a lower cost per unit.

OBJECTIVE

To compare the outcomes of MPLG stents versus triamcinolone-impregnated chitosan polymer (TICP) microsponge in frontal sinus surgery.

METHODS

Patients who underwent endoscopic sinus surgery from December 2018 to February 2022 were reviewed to identify those with the intraoperative placement of TICP microsponge or MPLG stent in the FSO. FSO patency was evaluated by endoscopy at follow-up. Twenty-two-item sinonasal outcome test (SNOT-22) was also recorded, and complications were noted.

RESULTS

A total of 68 subjects and 96 FSOs were treated. TICP was first used in August 2021 and MPLG in December 2018. MPLG placement in a Draf 3 cavity was excluded since TICP had not been used during Draf 3 procedure. Both cohorts (TICP 20 subjects, 35 FSOs; MPLG 26 subjects, 39 FSOs) had similar clinical characteristics. At a mean total follow-up of 249.2 days for TICP and 490.4 days for MPLG, FSO patency was 82.9% and 87.1%, respectively (P = .265). At an equivalent follow-up of 130.6 days in TICP and 154.0 days in MPLG, patency was 94.3% and 89.7%, respectively (P = .475). Both groups showed significant reductions in SNOT-22 (P < .001). MPLG demonstrated crusting within the FSO at 1 month (none in TICP).

CONCLUSION

FSO patency for both stents was similar, although TICP had significantly lower costs per unit. Additional comparative trials may be helpful for guiding clinicians on the appropriate clinical situations for the use of these devices.

Functional Analysis of Injectable Substance Treatment on Surgically Injured Rabbit Vocal Folds

OBJECTIVES

The objective of this study was to evaluate the efficacy of immediate injection treatments of dexamethasone, hyaluronic acid (HA)/gelatin (Ge) hydrogel and glycol-chitosan solution on the phonatory function of rabbit larynges at 42 days after surgical injury of the vocal folds, piloting a novel ex vivo phonatory functional analysis protocol.

METHODS

A modified microflap procedure was performed on the left vocal fold of 12 rabbits to induce an acute injury. Animals were randomized into one of four treatment groups with 0.1 mL injections of dexamethasone, HA/Ge hydrogel, glycol-chitosan or saline as control. The left mid vocal fold lamina propria was injected immediately following injury. The right vocal fold served as an uninjured control. Larynges were harvested at Day 42 after injection, then were subjected to airflow-bench evaluation. Acoustic, aerodynamic and laryngeal high-speed videoendoscopy (HSV) analyses were performed. HSV segments of the vibrating vocal folds were rated by three expert laryngologists. Six parameters related to vocal fold vibratory characteristics were evaluated on a Likert scale.

RESULTS

The fundamental frequency, one possible surrogate of vocal fold stiffness and scarring, was lower in the dexamethasone and HA/Ge hydrogel treatment groups compared to that of the saline control (411.52±11.63 Hz). The lowest fundamental frequency value was observed in the dexamethasone group (348.79±14.99 Hz). Expert visual ratings of the HSV segments indicated an overall positive outcome in the dexamethasone treatment group, though the impacts were below statistical significance.

CONCLUSION

Dexamethasone injections might be used as an adjunctive option for iatrogenic vocal fold scarring. An increased sample size, histological correlate, and experimental method improvements will be needed to confirm this finding. Results suggested a promising use of HSV and acoustic analysis techniques to identify and monitor post-surgical vocal fold repair and scarring, providing a useful tool for future studies of vocal fold scar treatments.

A comparison of effectiveness between Posisep and Merocel nasal packing after endoscopic sinus surgery: Findings from a randomized, double-blinded, controlled trial

BACKGROUND

The effectiveness of nonabsorbable and biodegradable nasal packing is still controversial, and the choice of nasal packing type can alter the outcome of endoscopic sinus surgery. This study compared the effectiveness of Posisep and Merocel as nasal packing materials with regard to hemostasis, adhesion, wound healing, patient's satisfaction and health-related quality of life after endoscopic sinus surgery (ESS).

METHODS

A prospective, randomized, double-blinded, controlled trial was conducted in patients with chronic rhinosinusitis refractory undergoing symmetrical bilateral ESS. At the completion of surgery, a nasal packing (either Merocel or Posisep) was randomly chosen and placed into the middle meatus of each nasal cavity. All patients were scheduled for follow-up visits at 24 hours, 5 days, 3 weeks, and 5 weeks days after surgery. Health-related quality of life was measured using the Sino-Nasal Outcome Test (SNOT-22). The overall inflammatory burden of chronic rhinosinusitis was measured by the Lund-Mackay postoperative endoscopic score (LMES).

RESULTS

Among 62 patients included in data analysis (n = 31 for each group), the mean age was 42.4 years and 54.8% were females. Patients with Posisep after ESS had more improvement and better symptoms measured through SNOT-22 and LMES at 24 hours, 5 days, and 3 weeks than those with Merocel after ESS. While some aspects measured by LMES such as discharge and scarring were still better until 5 weeks after surgery, all symptoms measured by SNOT-22 were similar between the 2 groups 5 weeks after surgery.

CONCLUSION

Posisep containing chitosan provided patients with a better quality of life throughout the early recovery period compared with Merocel. Although more studies are needed, our findings support the use of Posisep after ESS.

Haemostatic efficacy and inflammatory response of a novel beta-chitin patch in a cerebral small vessel injury model - A pilot study

OBJECTIVE

Rapid and efficacious haemostasis is paramount in neurosurgery. Assessing the efficacy and short- and long-term safety of haemostatic agents utilised within cerebral tissue is essential. This pilot study investigates the haemostatic efficacy and long-term safety of a novel beta-chitin patch against traditionally used agents, bipolar and Floseal, within cerebral tissue.

METHODS

Eighteen Merino sheep underwent standardised distal cortical vessel injury via temporal craniotomy. Sheep were randomised to receive 2 mls Floseal, 2 cm novel beta-chitin patch, or bipolar cautery to manage bleeding. All sheep underwent cerebral magnetic resonance imaging (MRI) at three months, before euthanasia and brain harvesting for histological assessment.

RESULTS

Beta-chitin demonstrated a trend towards a faster mean time to haemostasis (TTH) compared to Floseal (223.3 ± 199 s v. 259.8 ± 186.4 s), albeit non-significant (p = 0.234). Radiologically, cerebrocortical necrosis (p = 0.842) and oedema (p = 0.368) were noted slightly more frequently in the beta-chitin group. Histologically, severe fibrotic (p = 0.017) and granulomatous changes at the craniotomy sites were only present in the beta-chitin group (p = 0.002). Neuronal degeneration was seen in all with Floseal, but beta-chitin showed a trend towards more severe reaction when present. Bipolar use predominantly showed an inflammatory cortical reaction with substantial microvascular proliferation, and Floseal showed worse severity and depth of subpial oedema, however no statistical significance was reached.

CONCLUSION

All haemostats controlled bleeding, with beta-chitin demonstrating a non-inferior TTH compared to Floseal. However, it resulted in intense granulomatous and fibrotic changes, including degenerative neuronal reactions. More extensive studies are needed to assess these trends, to make further clinical inferences.

Chitogel following endoscopic sinus surgery promotes a healthy microbiome and reduces postoperative infections

BACKGROUND

Postoperative infections following endoscopic sinus surgery (ESS) impair wound healing and lead to poor outcomes. The aim of this study is to assess the effectiveness of Chitogel to reduce postoperative infections and restore a healthy microbiome following ESS.

METHODS

In this double-blinded randomized control trial, 25 patients undergoing ESS were prospectively recruited. At the end of surgery, patients were randomized to receive Chitogel to one side of the sinuses (allowing the other side to serve as control). Patients underwent routine follow-up with nasoendoscopies performed at 2, 6, and 12 weeks postoperatively. Sinus ostial measurements, microbiology, and microbiome swabs from bilateral sides were collected intraoperatively and at 12 weeks postoperatively. Additional swabs were collected if infection was present.

RESULTS

Improved endoscopic appearance of the sinuses (p = 0.03) and ostial patency were noted on the Chitogel side compared with control at 12 weeks (p < 0.001). A significant decrease in infections on the Chitogel side (12.0%) compared with control (52.0%) (p = 0.005) was evident. Following the use of Chitogel, there was a significant increase in the combined relative abundance of commensals Corynebacterium and Cutibacterium (Propionibacterium) from 30.15% at baseline to 46.62% at 12 weeks compared with control (47.18% to 40.79%) (p.adj = 0.01).

CONCLUSION

Chitogel significantly improved both the nasoendoscopic appearance of the sinuses and sinus ostial patency at 12 weeks postoperatively. Chitogel used following ESS helps restore an improved microbiome resulting in an increase in the relative abundance of commensals Corynebacterium and Cutibacterium (Propionibacterium). A significant decrease in postoperative infections was noted following use of Chitogel.

Effect of chitosan-based gel dressing on wound infection, synechia, and granulations after endoscopic sinus surgery of nasal polyps: A meta-analysis

A meta-analysis was performed to evaluate the effect of chitosan-based gel dressing on wound infection, synechia, and granulations after endoscopic sinus surgery of nasal polyps. A systematic literature search until March 2022 incorporated 386 subjects after endoscopic sinus surgery of nasal polyps at the beginning of the study; 187 were using chitosan-based gel dressing, and 199 were control. Statistical tools like the dichotomous method were used within a random or fixed-influence model to establish the odds ratio (OR) with 95% confidence intervals (CIs) to evaluate the influence of chitosan-based gel dressing on wound infection, synechia, and granulations after endoscopic sinus surgery of nasal polyps. Chitosan-based gel dressing had significantly lower wound infection (OR, 0.48; 95% CI, 0.25-0.92, P = 0.03), and synechia (OR, 0.25; 95% CI, 0.13-0.50, P < 0.001) compared with control in subjects with endoscopic sinus surgery of nasal polyps. However, no significant difference was found in granulations between chitosan-based gel dressing and control in subjects with endoscopic sinus surgery of nasal polyps. Chitosan-based gel dressing had significantly lower wound infection, synechia compared with control in subjects with endoscopic sinus surgery of nasal polyps, and no significant difference in granulations. Further studies are required to validate these findings.

Chitosan: A review of molecular structure, bioactivities and interactions with the human body and micro-organisms

Chitosan has many desirable attributes e.g. antimicrobial properties and promoting wound healing, and is used in various applications. This article first discusses how degree of deacetylation (DD) and molecular weight (MW) impacts on what level of bioactivities chitosan manifests, then introduces the "molecular chain configuration" model to explain various possible mechanisms of antimicrobial interactions between chitosan with different MW and different types of bacteria. Similarly, the possible pathways of how chitosan reacts with cancer and the body's immune system to demonstrate immune and antitumor effects are also discussed by using this model. Moreover, the possible mechanisms of how chitosan enhances coagulation and wound healing are also discussed. With these beneficial bioactivities in mind, the application of chitosan in surgery, tissue engineering and oncology is outlined. This review concludes that as chitosan demonstrates many beneficial bioactivities via multiple mechanisms, it is an important polymer with a promising future in medicine.

Comparison of Absorbable Packing versus No Packing in Wound Healing after Endoscopic Sinus Surgery: A Systematic Review and Pooled Analysis

INTRODUCTION

Nasal packing after endoscopic sinus surgery (ESS) is controversial. The aim of this systematic review was to compare absorbable packing versus no packing in wound healing after ESS for the treatment of chronic rhinosinusitis.

DATA SOURCE

English electronic databases, including Cochrane Library, EMBASE, MEDLINE, and PubMed, were searched, and only randomized controlled trials were included.

METHODS

The outcome measures were the presence of synechiae/adhesion formation, mucosal edema, crusting, granulation formation, and infection. The McNemar's test was used for pooled analysis.

RESULTS

Four studies with 148 participants were included. The pooled analysis showed that absorbable packing may offer benefit in reducing adhesion at 6-8 weeks (odds ratio [OR]: 0.3864; 95% confidence interval [CI]: 0.2136-0.7235) and 12 weeks (OR: 0.2396, 95% CI: 0.08267-0.7709) postoperatively compared with no packing. There was no significant difference between the packed and the unpacked side at 2, 6-8, and 12 weeks after ESS in terms of presence of crusting, edema, and granulation formation.

CONCLUSION

There is insufficient evidence to suggest that absorbable packing after ESS does not increase mucosal edema, granulation formation, and infection. However, the absorbable packing may be more effective than no packing for the prevention of mucosal adhesion after ESS. The use of absorbable nasal packing after ESS is recommended when used to reduce postoperative mucosal adhesion. More research in this area is clearly needed.

International consensus statement on allergy and rhinology: rhinosinusitis 2021

I.

EXECUTIVE SUMMARY

BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document.

METHODS

ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary.

RESULTS

ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided.

CONCLUSION

This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.

Prevention of adhesions post-abdominal surgery: Assessing the safety and efficacy of Chitogel with Deferiprone in a rat model

Introduction

Adhesions are often considered to be an inevitable consequence of abdominal and pelvic surgery, jeopardizing the medium and long-term success of these procedures. Numerous strategies have been tested to reduce adhesion formation, however, to date, no surgical or medical therapeutic approaches have been successful in its prevention. This study demonstrates the safety and efficacy of Chitogel with Deferiprone and/or antibacterial Gallium Protoporphyrin in different concentrations in preventing adhesion formation after abdominal surgery.

Materials and methods

112 adult (8–10 week old) male Wistar albino rats were subjected to midline laparotomy and caecal abrasion, with 48 rats having an additional enterotomy and suturing. Kaolin (0.005g/ml) was applied to further accelerate adhesion formation. The abrasion model rats were randomized to receive saline, Chitogel, or Chitogel plus Deferiprone (5, 10 or 20 mM), together with Gallium Protoporphyrin (250μg/mL). The abrasion with enterotomy rats were randomised to receive saline, Chitogel or Chitogel with Deferiprone (1 or 5 mM). At day 21, rats were euthanised, and adhesions graded macroscopically and microscopically; the tensile strength of the repaired caecum was determined by an investigator blinded to the treatment groups.

Results

Chitogel with Deferiprone 5 mM significantly reduced adhesion formation (p<0.01) when pathologically assessed in a rat abrasion model. Chitogel with Deferiprone 5 mM and 1 mM also significantly reduced adhesions (p<0.05) after abrasion with enterotomy. Def-Chitogel 1mM treatment did not weaken the enterotomy site with treated sites having significantly better tensile strength compared to control saline treated enterotomy rats.

Conclusions

Chitogel with Deferiprone 1 mM constitutes an effective preventative anti-adhesion barrier after abdominal surgery in a rat model. Moreover, this therapeutic combination of agents is safe and does not weaken the healing of the sutured enterotomy site.

[Radicality of maxillary sinus surgery and size of the maxillary sinus ostium]

Until the 1990s, radical sinus surgery was considered a standard procedure for maxillary sinus diseases, but it is no longer favored due to the high morbidity. Today, functional endoscopic sinus surgery (FESS) is considered the gold standard in sinus surgery. Modifications of surgical approaches also allow access to regions of the maxillary sinus that were previously difficult to reach. Depending on anatomy and pathology, different methods for widening the maxillary ostium can be selected. In type I sinusotomy, the natural ostium is widened dorsally by a maximum of 1 cm. Sinusotomy type II involves widening the natural ostium up to a maximum diameter of 2 cm. In sinusotomy type III, the natural ostium is widened dorsally to the posterior wall of the maxillary sinus and caudally to the base of the inferior turbinate. Beside the prelacrimal approach, more invasive approaches are the medial maxillectomy, in which the dorsal part of the inferior turbinate and the adjacent medial wall of the maxillary sinus is resected, as well as its modifications "mega antrostomy" and "extended maxillary antrostomy." Correct selection of the size of the maxillary sinus window is prerequisite for successful treatment and long-term postoperative success. Isolated purulent maxillary sinusitis can usually be treated by a type I sinusotomy. Sinusotomy type II addresses nasal polyps with involvement of the mucosa of the ostium, recurrent stenosis after previous surgery, chronic maxillary sinusitis due to cystic fibrosis, and purulent maxillary sinusitis with involvement of other adjacent sinuses. Sinusotomy type III is required for choanal polyps with attachment to the floor of the maxillary sinus, for extensive polyposis and fungal sinusitis, and for inverted papilloma. Particularly for (recurrent) disease and extensive interventions in the maxillary sinus, medial maxillectomy or a modification thereof may be required.

Prevention of peridural adhesions in spinal surgery: Assessing safety and efficacy of Chitogel with Deferiprone in a sheep model

INTRODUCTION

Spinal laminectomy is a common procedure performed to relieve neural compression in patients suffering from myelopathy or radiculopathy. However, up to 40% of patients suffer from persistent post-operative pain and disability, a condition known as Failed Back Surgery Syndrome (FBSS). Excessive scarring in the surgical bed is implicated as a cause. Hydrogels have been proposed to prevent adhesion formation post-laminectomy; however, their efficacy has not been proven. This study uses Chitogel complexed with the iron chelator Deferiprone (Def) to prevent adhesion formation in a sheep laminectomy model.

MATERIAL & METHODS

Fifteen Adult Merino sheep (Ovis Aries, 1-5 yrs old) underwent laminectomy at lumbar levels 1-5 and had hydrated aluminum silicate (kaolin) applied to promote adhesion formation. Subjects were randomised to receive at each laminectomy level no-treatment control, Chitogel, Chitogel with Def at 20 mM or 40 mM or Carboxy-methyl-cellulose and Polyethylene oxide (CMC/PEO) gel. The animals were recovered for 3 months post-surgery, followed by assessment with Magnetic Resonance Imaging (MRI) and histopathology of the spinal tissues for evaluating the presence and extent of adhesions.

RESULTS

MRI and Histology assessment indicated that Kaolin induced severe inflammation with adhesion formation. Chitogel with and without 20 mM Def decreased inflammation (p < 0.01) and trended to reduce adhesions (p < 0.1). Chitogel with Def 40 mM was not significantly dis-similar to CMC/PEO and did not reduce inflammation or adhesions compared to no-treatment control.

CONCLUSION

Chitogel in combination with Def 20 mM is safe and effective in decreasing the inflammatory process and may possibly reduce post-operative adhesions following laminectomy.

Current and Alternative Therapies for Nasal Mucosa Injury: A Review

Nasal mucosa injury can be caused by trauma, radiotherapy, chronic infection such as sinusitis, and post sinus surgery. The rate of healing and its treatment are important in the recovery of patients especially in post sinus surgery, which introduces new injuries. In this review, the current knowledge in terms of the mechanism underlying nasal wound healing was initially discussed. The currently available treatment options for enhancement of wound healing following sinus surgery were discussed and these had included intravenous antibiotics or steroids, various nasal sprays, and nasal packing. In addition, emerging alternative therapies in nasal mucosa wound healing such as herbal medicine and the advancement of regenerative medicine therapies such as stem cells and their byproducts were also discussed. Despite the various available treatment options for wound healing in nasal mucosa, rigorous strong evidence of their efficacy is gravely warranted in order to recommend them as part of the treatment modality.

Influence of chitosan-based dressing on prevention of synechia and wound healing after endoscopic sinus surgery: A meta-analysis

INTRODUCTION

Endoscopic sinus surgery (ESS) has had many complications, e.g., synechia formation. This meta-analysis investigated the effect of a novel chitosan-based dressing on prevention of synechia and wound healing after ESS.

METHODS

We systematically searched various medical literature data bases and included the randomized controlled trials (RCT) regarding the effect of novel chitosan-based dressing on ESS. The study outcomes included synechia, granulations, hemostasis, crusting scores, and infection.

RESULTS

Six RCTs, which involved 337 patients, were included in the meta-analysis. Compared with control intervention after ESS, chitosan-based gel dressing substantially inhibited synechia (risk ratio [RR] 0.28 [95% confidence interval {CI}, 0.15-0.54]; p = 0.0001), improved granulations (RR 1.47 [95% CI, 1.07-2.03]; p = 0.02), and hemostasis (RR 1.47 [95% CI, 1.07-2.03]; p = 0.02) but demonstrated no effect on crusting scores (standard mean difference -0.41 [95% CI, -1.06 to 0.23]; p = 0.21) and infection (RR 0.88 [95% CI, 0.51-1.52]; p = 0.64).

CONCLUSION

Compared with control intervention, chitosan-based dressing was associated with significantly reduced synechia and with increased granulations and hemostasis but showed no influence on crusting and infection after ESS.

Outcomes and Complications of Balloon and Conventional Functional Endoscopic Sinus Surgery

Background

Since the Food and Drug Administration approval of balloon sinuplasty (BSP) in 2005, no nationally representative population-based studies have examined the outcomes and adverse events of BSP.

Objective

To assess the rates of complications and revision surgery in patients who received BSP, functional endoscopic sinus surgery (FESS), or a hybrid procedure.

Methods

Using one of the nation’s largest commercial insurance databases, we conducted a retrospective cohort study of pediatric and adult patients diagnosed with chronic rhinosinusitis between 2011 and 2014 who underwent BSP, conventional FESS, or a hybrid procedure. The primary outcomes were surgical complication and revision rates within 6 months of initial surgery.

Results

A total of 16,040 patients who underwent sinus surgery were included. Overall, 2,851 patients underwent BSP, 11,955 underwent conventional FESS, and 1 234 underwent a hybrid procedure. BSP surgery was more likely to have been performed in an office setting (86.53%) compared to FESS (0.74%). The complication rate was 5.26% for BSP and 7.35% for conventional FESS. Revision rates were 7.89% for BSP, 16.85% for FESS, and 15.15% for a hybrid procedure.

Conclusion

Despite the low overall risk, major complications occur with BSP including cerebrospinal fluid leak, pneumocephalus, orbital complications, and severe bleeding. Otolaryngologists should discuss these risks with their patients. Prospective studies are still needed to compare outcomes of BSP with those of FESS.

Safety and Efficacy of Topical Chitogel- Deferiprone-Gallium Protoporphyrin in Sheep Model

Objectives: Increasing antimicrobial resistance has presented new challenges to the treatment of recalcitrant chronic rhinosinusitis fuelling a continuous search for novel antibiofilm agents. This study aimed to assess the safety and efficacy of Chitogel (Chitogel®, Wellington New Zealand) combined with novel antibiofilm agents Deferiprone and Gallium Protoporphyrin (CG-DG) as a topical treatment against S. aureus biofilms in vivo.

Methods: To assess safety, 8 sheep were divided into two groups of 7 day treatments (n = 8 sinuses per treatment); (1) Chitogel (CG) with twice daily saline flush, and (2) CG-DG gel with twice daily saline flush. Tissue morphology was analyzed using histology and scanning electron microscopy (SEM). To assess efficacy we used a S. aureus sheep sinusitis model. Fifteen sheep were divided into three groups of 7 day treatments (n = 10 sinuses per treatment); (1) twice daily saline flush (NT), (2) Chitogel (CG) with twice daily saline flush, and (3) CG-DG gel with twice daily saline flush. Biofilm biomass across all groups was compared using LIVE/DEAD BacLight stain and confocal scanning laser microscopy.

Results: Safety study showed no cilia denudation on scanning electron microscopy and no change in sinus mucosa histopathology when comparing CG-DG to CG treated sheep. COMSTAT2 assessment of biofilm biomass showed a significant reduction in CG-DG treated sheep compared to NT controls.

Conclusion: Results indicate that CG-DG is safe and effective against S. aureus biofilms in a sheep sinusitis model and could represent a viable treatment option in the clinical setting.

Posterior translacrimal approach to the maxillary sinus

Background:

This study aimed to compare the view into the maxillary sinus using the posterior translacrimal approach compared with grade 3 antrostomy.

Methods:

Grade 3 antrostomy followed by a posterior translacrimal approach was performed on four cadavers. The maximum intramaxillary view was documented endoscopically guided by electromagnetic navigation. Representative screenshots were evaluated in a blinded manner by three independent sinus surgeons. In addition, a prospective investigation of specific complications in the post-operative course of consecutive patients was performed.

Results:

In the cadaver study, the posterior translacrimal approach provided a significantly better view into the maxillary sinus compared with grade 3 antrostomy. In the clinical study, only 1 out of 20 patients reported on a minor problem with lacrimal drainage at 6 months.

Conclusion:

The posterior translacrimal approach to visualising the maxillary sinus should be considered a strong alternative to more radical techniques.

Efficacy of chitosan dressing on endoscopic sinus surgery: a systematic review and meta-analysis

Chitosan dressing might be promising to promote the recovery following endoscopic sinus surgery (ESS). However, the results remain controversial. We conducted a systematic review and meta-analysis to explore the influence of chitosan dressing on ESS. PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases were systematically searched. Randomized controlled trials (RCTs) assessing the effect of chitosan dressing on endoscopic sinus surgery were included. Two investigators independently searched articles, extracted data, and assessed the quality of included studies. The primary outcomes were synechia and hemostasis. Meta-analysis was performed using random-effect model. Four RCTs involving 268 patients were included in the meta-analysis. Overall following ESS, compared with control intervention, chitosan dressing significantly reduced synechia (RR = 0.25; 95% CI 0.13-0.49; P < 0.0001) and promoted hemostasis (RR = 1.70; 95% CI 1.37-2.11; P < 0.00001), but showed no impact on granulations (RR = 1.18; 95% CI 0.72-1.95; P = 0.52), mucosal edema (RR = 0.88; 95% CI 0.60-1.29; P = 0.51), crusting (RR = 0.85; 95% CI 0.48-1.53; P = 0.60), and infection (RR = 0.88; 95% CI 0.51-1.52; P = 0.64). Compared to control intervention, chitosan dressing could significantly decrease edema and improve hemostasis, but had no effect on granulations, mucosal edema, crusting and infection.

Efficacy and Safety of 3 Nasal Packing Materials Used After Functional Endoscopic Sinus Surgery for Chronic Rhinosinusitis: A Comparative Study in China

Background

This study aimed to investigate the efficacy and safety of 3 nasal packing products (silicone tube, Beschitin-F, and Aquacel1-Ag) after functional endoscopic sinus surgery (FESS) for chronic rhinosinusitis (CRS) patients in China.

Material/Methods

Sixty-six CRS patients undergoing FESS surgery were randomly divided into 3 groups (22 patients in each group): the silicone tube group, the Beschitin-F group, and the Aquacel1-Ag group. Postoperative headache, nasal pain, nasal bleeding, and swelling of the nasal mucosa were observed at 1 month after FESS surgery. Bacteriology of chronic rhinosinusitis was conducted by culturing the removed nasal packing.

Results

The VAS scores of nasal pain in the silicone tube group were lower than in the Beschitin-F and the Aquacel1-Ag groups. The volume of nasal bleeding in the Beschitin-F group was higher than in the silicone tube and Aquacel1-Ag groups. The adhesion rate of the nasal cavity in the Beschitin-F1 group (2/22, 9.1%) was also higher than in the silicone tube group (0/22, 0%) and the Aquacel1-Ag group (0/22, 0%). The results of bacterial culture from removed nasal packing showed that coagulase-negative staphylococci (CNS) was more frequent in the silicone tube group than in the Beschitin-F and Aquacel1-Ag groups, but Streptococcus pneumonia, Haemophilus influenza, and Gram-negative rods were more common in the Aquacel1-Ag group than in the silicone tube and Beschitin-F groups.

Conclusions

These results indicate that the silicone tube may be more effective and safe than Beschitin-F and Aquacel1-Ag as nasal packing after FES surgery for CRS.

Advances in Absorbable Biomaterials and Nasal Packing

Nasal biomaterials have been developed to improve postoperative outcomes after functional endoscopic sinus surgery (FESS). These products have been designed to overcome certain common complications in FESS, and to maximize patient comfort. This article evaluates the performance of nonabsorbable and absorbable packing with respect to these outcomes. The collected trials suggest superior performance of bioabsorbable packs compared with absorbable packs with respect to patient comfort. For hemostasis and wound healing, variation in performance metrics makes interstudy comparison difficult. Before further trials are conducted, consensus must be reached among rhinologists as to the proper method of evaluating these products.

Chitosan promotes aquaporin formation and inhibits mucociliary differentiation of nasal epithelial cells through increased TGF-β1 production

Although endoscopic sinus surgery is the mainstay surgical treatment for chronic rhinosinusitis, over 15% of patients require a repeat operation wherein postoperative adhesion formation is one of the main causes of failure. Several recently proposed chitosan-based biomaterials promote mucosal healing, reduce postoperative adhesion formation and restore mucociliary function of sinonasal mucosa. However, the effects of chitosan on cellular morphology, re-epithelization, and mucociliary differentiation of nasal epithelial cells (NECs) during the wound healing process have not been thoroughly investigated. The present study investigates the direct effects of chitosan on cellular growth, cellular migration, mucociliary differentiation and aquaporin (AQP) formation of NECs to elucidate the role of chitosan in sinonasal applications. Wound healing assay reveals that proliferation and migration of NECs are inhibited by incubation of chitosan. The NECs become irregular in shape without formation of tight junction and mucociliary differentiation of NECs is inhibited during a culture period with incubation of chitosan. However, AQP3 and AQP5 formation in NECs is significantly higher in chitosan groups than in control groups. Further, expressions of transforming growth factor (TGF)-β1, Smad2, and Smad3 are significantly higher in the chitosan groups compared with controls. The results of the comparison indicate that chitosan inhibits proliferation, migration and mucociliary differentiation of NECs through increasing production of TGF-β1. Copyright © 2016 John Wiley & Sons, Ltd.

Biomaterials in Rhinology

Introduction

Many different kinds of rhinologic biomaterials, both nonabsorbable and absorbable, have been developed over the years to improve outcomes following endoscopic sinus surgery (ESS) for patients with chronic rhinosinusitis. In particular, these products have been designed to prevent postoperative bleeding, optimize the wound healing process, and reduce inflammation. This review evaluates the most recent evidence on biomaterials used in rhinology, focusing on these outcomes after ESS.

Data Sources

MEDLINE, Scopus, Google Scholar, and Clinicaltrials.gov.

Review Methods

A primary literature search based on the listed databases was performed with combinatorial search terms. Studies were considered for review if they met a set of inclusion and exclusion criteria.

Conclusions

Some products have performed better than others in clinical trials, although significant heterogeneity among studies does not allow for selection of a clearly superior biomaterial. While nonabsorbable biomaterials are still effective in achieving certain outcomes, newer, absorbable substances may be just as effective and avoid the morbidity associated with nasal packing removal. Steroid-eluting biomaterials have shown promising early results in reducing inflammation and promoting wound healing.

Implications for Practice

Certain absorbable biomaterials, such as chitosan gel and fibrin glue, have performed well with respect to postoperative hemostasis and wound healing, although they do not address mucosal inflammation. Steroid delivery systems may play an increasingly important role in reducing disease recurrence after ESS, although more studies are needed to assess long-term outcomes.

Comprehensive review on endonasal endoscopic sinus surgery

Endonasal endoscopic sinus surgery is the standard procedure for surgery of most paranasal sinus diseases. Appropriate frame conditions provided, the respective procedures are safe and successful. These prerequisites encompass appropriate technical equipment, anatomical oriented surgical technique, proper patient selection, and individually adapted extent of surgery. The range of endonasal sinus operations has dramatically increased during the last 20 years and reaches from partial uncinectomy to pansinus surgery with extended surgery of the frontal (Draf type III), maxillary (grade 3-4, medial maxillectomy, prelacrimal approach) and sphenoid sinus. In addition there are operations outside and beyond the paranasal sinuses. The development of surgical technique is still constantly evolving. This article gives a comprehensive review on the most recent state of the art in endoscopic sinus surgery according to the literature with the following aspects: principles and fundamentals, surgical techniques, indications, outcome, postoperative care, nasal packing and stents, technical equipment.

Product comparison model in otolaryngology: Equivalency analysis of absorbable hemostatic agents after endoscopic sinus surgery

OBJECTIVES/HYPOTHESIS

Evidence-based medicine in otolaryngology literature continues to be lacking, especially with regard to new products brought to market. The marketing of products often includes statements of benefit that have limited objective support in research or literature. To address this, and to adequately determine product equivalency/superiority, careful evaluation must be made. In order to establish standards for this process in rhinology products, we directly compare three different absorbable hemostatic agents in patients with chronic rhinosinusitis (CRS) after undergoing endoscopic sinus surgery (ESS), using both objective and subjective outcomes.

STUDY DESIGN

Double-blinded prospective (level 1) comparison and equivalency analysis of three plant-based absorbable hemostatic agents (carboxymethylcellulose [CMC] gel, mucopolysaccharide hemospheres (MPH), and potato starch wafer) in patients undergoing bilateral ESS.

METHODS

Patients with medically refractory CRS who underwent bilateral ESS were recruited and prospectively followed. At the conclusion of ESS, one of three different hemostatic agents was applied to each nasal passage. Subjective patient data was obtained using rated symptoms compared between the two sides (nasal obstruction, bleeding, pain, and nasal discharge) at baseline and on postoperative days 1, 7, and 14. Objective data was obtained by blinded endoscopic scoring to rate mucosal edema, inflammation, granulation, crusting, infection, and synechiae formation on postoperative weeks 1, 3, and 6.

RESULTS

Forty-eight patients who underwent ESS for CRS were included. There is no statistical difference in subjective scores for any of the variables measured, although (MPH) nearly reached statistical significance at postoperative day 7 for increased pain (P = 0.06) and obstruction (P = 0.22). Objective measures showed equivalency between all products, except the CMC gel approached significance at week 3 for increased crusting (P = 0.10), granulation (P = 0.24), and debridement (P = 0.07). At 6 weeks, increased debridement (P = 0.14) also approached significance.

CONCLUSION

Careful and deliberate consideration should be taken when choosing products to assist our surgical endeavors. Subjectively, patients treated with MPH showed near-significant increases in pain and obstruction. In objective measures, CMC gel nearly reaches significance for more postoperative debridement, with increased crusting and inflammation. Product choice could consider these factors, although it remains at the discretion of the surgeon. This model of comparison allows careful product comparison and should be applied to other hemostatics, as well as other materials in use in otolaryngology.

LEVEL OF EVIDENCE

1b. Laryngoscope, 126:S5-S13, 2016.

A golden experience: Fifty years of experience managing the frontal sinus

OBJECTIVES/HYPOTHESIS

The frontal sinus is one of the most anatomically complex and inaccessible of the paranasal sinuses. As a result, surgeons have continually tried to improve surgical management of the frontal sinus. The senior author (c.w.g.) shares 50 years of experience managing the frontal sinus.

DATA SOURCES

PubMed literature search.

REVIEW METHODS

Review of the literature regarding landmark innovations in frontal sinus surgery.

RESULTS

Open approaches established that the frontal sinus is accessible, and in certain circumstances, such as with large osteoma or papilloma, are still required. The endoscope changed the surgical landscape and allowed for greater finesse and decreased morbidity. Sinus balloon dilation is the newest change in frontal sinus management and shows promise in properly selected cases.

CONCLUSION

Surgery of the frontal sinus continues to evolve and improve. Although there are new techniques, the older techniques are still pertinent.

Reducing the Oxidation Level of Dextran Aldehyde in a Chitosan/Dextran-Based Surgical Hydrogel Increases Biocompatibility and Decreases Antimicrobial Efficacy

A highly oxidized form of a chitosan/dextran-based hydrogel (CD-100) containing 80% oxidized dextran aldehyde (DA-100) was developed as a post-operative aid, and found to significantly prevent adhesion formation in endoscopic sinus surgery (ESS). However, the CD-100 hydrogel showed moderate in vitro cytotoxicity to mammalian cell lines, with the DA-100 found to be the cytotoxic component. In order to extend the use of the hydrogel to abdominal surgeries, reformulation using a lower oxidized DA (DA-25) was pursued. The aim of the present study was to compare the antimicrobial efficacy, in vitro biocompatibility and wound healing capacity of the highly oxidized CD-100 hydrogel with the CD-25 hydrogel. Antimicrobial studies were performed against a range of clinically relevant abdominal microorganisms using the micro-broth dilution method. Biocompatibility testing using human dermal fibroblasts was assessed via a tetrazolium reduction assay (MTT) and a wound healing model. In contrast to the original DA-100 formulation, DA-25 was found to be non-cytotoxic, and showed no overall impairment of cell migration, with wound closure occurring at 72 h. However, the lower oxidation level negatively affected the antimicrobial efficacy of the hydrogel (CD-25). Although the CD-25 hydrogel's antimicrobial efficacy and anti-fibroblast activity is decreased when compared to the original CD-100 hydrogel formulation, previous in vivo studies show that the CD-25 hydrogel remains an effective, biocompatible barrier agent in the prevention of postoperative adhesions.

Randomized controlled trial: hybrid technique using balloon dilation of the frontal sinus drainage pathway

BACKGROUND

The objectives of this study were as follows: (1) to evaluate frontal sinus ostial patency following balloon dilation with the Ventera Sinus Dilation System, compared with frontal sinusotomy (Draf 2a); and (2) to compare mean blood loss and mean surgical time for frontal sinusotomy using balloon dilation compared with traditional surgical methods.

METHODS

A single blinded, randomized, controlled, prospective study was performed at St. Paul's Sinus Center, Vancouver, a tertiary referral rhinology center. Thirty patients undergoing functional endoscopic sinus surgery (FESS) for chronic rhinosinusitis (CRS) were randomized to a hybrid approach with exposure of the frontal recess using standard instrumentation and then balloon dilation of 1 frontal sinus drainage pathway and traditional frontal sinusotomy for the opposite side. Blood loss and surgical time for opening the frontal sinus drainage pathway was recorded for each side. Patients acted as their own controls. Ostial patency and size were assessed 5 weeks and 3 months postoperatively using endoscopy. Ostial patency was also recorded at 1 year following surgery.

RESULTS

All frontal sinus ostia in both groups (n = 30) were successfully opened and were patent with both techniques 3 months postoperatively. All frontal sinus ostia assessed at 1 year (73%) remained patent and none required revision frontal surgery. Balloon dilation showed a mean surgical time of 655 seconds compared to 898 seconds for traditional FESS (p = 0.03). Mean blood loss was less with balloon dilation (58 mL vs 91 mL; p = 0.008).

CONCLUSION

A hybrid balloon technique successfully dilates the frontal sinus drainage pathway with reduced blood loss. Also, short-term patency appears to be comparable to traditional frontal sinusotomy.