Efficacy, tolerability and patient benefit of ultrasound-assisted wound treatment versus surgical debridement: a randomized clinical study

Ultrasonic Debridement of Fournier Gangrene

Ultrasonic debridement devices are minimally invasive and effective for biofilm removal, allowing for debridement of necrotic tissue while minimizing damage to normal tissues, such as the blood vessels and nerves. The use of ultrasonic debridement has been reported for foot ulcers and pressure ulcers but not Fournier gangrene. The perineal area, which is difficult to surgically debride using electrocautery, is a suitable site for the use of an ultrasonic debridement device because of its proximity to vital organs. We report here a case of Fournier gangrene that healed with testicular sparing using an ultrasonic debridement device.

Use of low-frequency contact ultrasonic debridement with and without polyhexamethylene biguanide in hard-to-heal leg ulcers: an RCT

OBJECTIVE

The primary aim of this research was to investigate the combination effect of polyhexamethylene biguanide (PHMB) and low-frequency contact ultrasonic debridement (LFCUD) on the bacterial load in hard-to-heal wounds in adults, compared with ultrasonic debridement alone. Secondary outcomes included wound healing, quality of life (QoL) and pain scores.

METHOD

In this single-blinded, randomised, controlled trial participants were randomised to two groups. All participants received LFCUD weekly for six weeks, plus six weeks of weekly follow-up. The intervention group received an additional 15-minute topical application of PHMB post-LFCUD, at each dressing change and in a sustained dressing product. The control group received non-antimicrobial products and the wounds were cleansed with clean water or saline. Wound swabs were taken from all wounds for microbiological analysis at weeks 1, 3, 6 and 12.

RESULTS

A total of 50 participants took part. The intervention group (n=25) had a lower bacterial load at week 12 compared with the control group (n=25) (p<0.001). There was no difference in complete wound healing between the groups (p=0.47) or wound-related QoL (p=0.15). However, more wounds deteriorated in the control group (44%) compared with the intervention group (8%, p=0.01). A higher proportion of wounds reduced in size in the intervention group (61% versus 12%, p=0.019). Pain was lower in the intervention group at week six, compared with controls (p=0.04).

CONCLUSION

LFCUD without the addition of an antimicrobial agent such as PHMB, cannot be recommended. Further research requires longer follow-up time and would benefit from being powered sufficiently to test the effects of multiple covariates.

Ultrasound-Assisted Wound (UAW) Debridement in the Treatment of Diabetic Foot Ulcer: A Systematic Review and Meta-Analysis

A systematic review and meta-analysis were carried out to investigate the effect of ultrasound-assisted wound (UAW) debridement in patients with diabetic foot ulcers (DFUs). All selected studies were evaluated using the Cochrane risk of bias tool to assess the risk of bias for randomized controlled trials. PubMed and Web of Science were searched in October 2021 to find randomized clinical trials (RCT) assessing the effect of UAW debridement on DFUs. RevMan v5.4. was used to analyze the data with the Mantel-Haenszel method for dichotomous outcomes. A total of 8 RCT met our inclusion criteria, with 263 participants. Concerning the healing rate comparing UAW versus the control group, a meta-analysis estimated the pooled OR at 2.22 (95% CI 0.96-5.11, p = 0.06), favoring UAW debridement, with low heterogeneity (x² = 7.47, df = 5, p = 0.19, I² = 33%). Time to healing was similar in both groups: UAW group (14.25 ± 10.10 weeks) versus the control group (13.38 ± 1.99 weeks, p = 0.87). Wound area reduction was greater in the UAW debridement group (74.58% ± 19.21%) than in the control group (56.86% ± 25.09%), although no significant differences were observed between them (p = 0.24). UAW debridement showed higher healing rates, a greater percentage of wound area reduction, and similar healing times when compared with placebo (sham device) and standard of care in patients with DFUs, although no statistically significant differences were observed between groups.

Wound Healing in the Golden Agers: What We Know and the Possible Way Ahead

While "population aging" is an accomplishment that deserves acclamation, it is in itself a tremendous challenge. Age-related skin changes, impaired wound healing, and concurrent comorbidities are the deadly triad that contribute most to the development of nonhealing chronic wounds in the elderly. This imposes enormous medical, social, and financial burden. With the rising trend in the aging population, this problem is likely to exacerbate unless multidisciplinary, rapt wound care strategies are developed. The last decade was dedicated to understand the basic biology underlying the wound healing process but most in vitro and animal model studies translated poorly to human conditions. Forthcoming, the focus is on the development of diagnostic and therapeutic strategies to improve healing in this vulnerable age group. Further, understanding the complex pathobiology of cellular senescence and wound healing process is required to develop focused therapy for these "problem wounds" in the elderly.

Ultrasonic-assisted wound debridement: report from a closed panel meeting

Mechanical debridement can be considered as an alternative to surgical debridement if surgery is not available, or is considered impractical or too high risk. One form of selective mechanical debridement is ultrasonic-assisted wound (UAW) debridement. As the published evidence on this is limited, a closed international expert meeting was held to review the existing evidence base on it, present preliminary findings of research currently in progress and discuss individual cases selected from the clinical experts' own practice. The panel also explored the potential barriers to the implementation of UAW debridement and how these might be addressed. It concluded there is sufficient evidence that UAW debridement is an effective method of cleansing and debriding almost all hard-to-heal wounds. Patients who are most likely to benefit from it are not medically stable, on anticoagulants, unable to visit a hospital for wound treatment, and/or have wounds with a poor vascular supply or are close to critical structures. The panel also observed that UAW debridement can be used to prepare the wound for negative pressure wound therapy (NPWT) or as an adjunctive to it. Given the potential to experience pain during the procedure, the panel considered that patients will benefit from topical analgesia. The panel noted that health professionals, patients and visitors must be protected from the aerosolisation associated with UAW, to reduce risk of cross-contamination.

Treatment of prosthetic vascular graft infection in the groin with ultrasound debridement: A case report

Introduction

Prosthetic graft infection (PGI) is associated with low patient survival rates. The effectiveness of ultrasound debridement in chronic wound healing has been previously reported; however, data on the use of ultrasound technology and its effect on the treatment of PGI are still lacking. We report a case in which PGI in the groin was managed by graft removal using ultrasound debridement.

Presentation of case

A 70-year-old man was diagnosed with chronic limb-threatening ischemia and underwent a femoral-femoral bypass with a polytetrafluoroethylene graft. Eight months postoperatively, he developed an infection at the femoral incision site. Graft removal was performed using ultrasound debridement. The estimated blood loss was 10 mL. The wound healed, and the patient has remained in good health for 2 years postoperatively.

Discussion

When the ultrasonic probe is applied to the wound, ultrasonic energy penetrates into the tissue, and a fibrinolytic action removes necrotic or infected tissue without removing healthy tissue, thereby minimizing bleeding. Using this technique, we were able to perform effective debridement at not only the wound but also the anastomosis.

Conclusion

It is our opinion that this technique can be used to achieve adequate debridement with little bleeding during graft removal and may provide a new option for the treatment of PGI.

Crustacean Proteases and Their Application in Debridement

Digestive proteases from marine organisms have been poorly applied to biomedicine. Exceptions are trypsin and other digestive proteases from a few cold-adapted or temperate fish and crustacean species. These enzymes are more efficient than enzymes from microorganism and higher vertebrates that have been used traditionally. However, the biomedical potential of digestive proteases from warm environment species has received less research attention. This review aims to provide an overview of this unrealised biomedical potential, using the debridement application as a paradigm. Debridement is intended to remove nonviable, necrotic and contaminated tissue, as well as fibrin clots, and is a key step in wound treatment. We discuss the physiological role of enzymes in wound healing, the use of exogenous enzymes in debridement, and the limitations of cold-adapted enzymes such as their poor thermal stability. We show that digestive proteases from tropical crustaceans may have advantages over their cold-adapted counterparts for this and similar uses. Differences in thermal stability, auto-proteolytic stability, and susceptibility to proteinase inhibitors are discussed. Furthermore, it is proposed that the feeding behaviour of the source organism may direct the evaluation of enzymes for particular applications, as digestive proteases have evolved to fill a wide variety of feeding habitats, natural substrates, and environmental conditions. We encourage more research on the biomedical application of digestive enzymes from tropical marine crustaceans.

Ultrasound-assisted debridement of neuroischaemic diabetic foot ulcers, clinical and microbiological effects: a case series

OBJECTIVE

To evaluate the clinical and microbiological effects of sequential wound debridement in a case series of neuroischaemic diabetic foot ulcers (DFUs) using an ultrasound-assisted wound debridement (UAW) device.

METHOD

A prospective, single-centre study, involving a case series of 24 neuroischaemic DFUs, was conducted to evaluate sequential wound debridement with UAW during a six-week treatment period. Soft tissue punch biopsies were taken every second week of treatment, both before and after wound debridement sessions. Qualitative and quantitative microbiological analysis was performed and wounds were assessed at patient admission, and before and after each debridement procedure.

RESULTS

Wound tissue quality scores improved significantly from a mean score of 2.1±1.3 points at patient inclusion, to 5.3±1.7 points (p=0.001). Mean wound sizes were 4.45cm² (range: 2-12.25cm²) at week zero, and 2.75cm² (range: 1.67-10.70cm²) at week six (p=0.04). The mean number of bacterial species per culture determined at week zero and at week six was 2.53±1.55 and 1.90±1.16, respectively (p=0.023). Wound debridement resulted in significant decreases in bacterial counts (1.17, 1.31 and 0.77 log units in colony forming units (CFU) for week zero, three and six, respectively). The average bacterial load in tissue samples before and after wound debridement after the six-week treatment was Log 5.55±0.91CFU/g and Log 4.59±0.89CFU/g, respectively (p<0.001).

CONCLUSIONS

The study results showed a significant bacterial load reduction in DFU tissue samples as a result of UAW debridement, independent of bacterial species, some of which exhibited antibiotic-resistance. Significant bacterial load reduction was correlated with improved wound conditions and significant reductions of wound size.

Biofilm management using monofilament fibre debridement technology: outcomes and clinician and patient satisfaction

Objective:

Best practice in wound bed preparation and biofilm-based wound management includes debridement to create a clean wound bed and to assist in minimising the redevelopment of biofilm. Biofilm that is not removed inhibits healing and redevelops if not prevented from doing so with topical antimicrobial agents. Monofilament fibre debriding technology (MFDT) is used for effective and rapid mechanical debridement of loose material, slough and biofilm. The objective of this evaluation was to determine the clinical effect and consequential levels of health professional and patient satisfaction with the results of a biofilm pathway that included MFDT to achieve debridement.

Methods:

This non-comparative, open label evaluation was conducted in static and non-static wounds that required debridement. MFDT was used to debride in a two-week evaluation of a biofilm pathway. Wounds were debrided three times in week one and twice in week two. Each debridement was followed by treatment with an antimicrobial dressing. Other care included secondary dressings and compression delivered according to local practice, guidelines and formularies. After the clinical evaluation, health professionals were invited to complete an online survey of the clinical outcomes and their satisfaction with the biofilm pathway.

Results:

There were 706 health professionals who provided answers to the survey questions. Wound types evaluated were leg ulcers (67.4%), pressure ulcers (10%), dehisced surgical wounds (1.7%), diabetic foot ulcers (7.4%) and other wounds (13.4%). Of the wounds, 9% were reported as non-static despite the eligibility criteria. Not all wounds followed the pathway. The most frequently-used antimicrobial was silver. Non-antimicrobial products used included all-in-one dressings, other secondary dressings and compression. There was a change in 77% of wounds overall after two weeks. Change was reported almost equally for both static and non-static wounds. Health professionals who did or did not follow the pathway were ‘completely satisfied’ or ‘satisfied’ with the overall clinical outcome 96% and 95%, respectively. Of the patients, 77% were ‘completely satisfied’ or ‘satisfied’ with healing after following the pathway, as reported by the treating health professional.

Conclusion:

The biofilm pathway that includes MFDT appears effective. Wounds managed on the pathway were debrided effectively and healing progressed to the satisfaction of both health professionals and patients.

Effectiveness of biofilm-based wound care system on wound healing in chronic wounds

A biofilm plays a crucial role in delaying wound healing. Sharp debridement, a possible effective method for eliminating biofilms, can only be applied to the wound with visible necrotic tissue; thus, no option has been available for eliminating biofilms that are not accompanied by necrotic tissue. Wound blotting was recently developed to visualize biofilm noninvasively and quickly, and ultrasonic debridement is available for biofilm removal. Therefore, the purpose of this study was to investigate the efficacy of "biofilm-based wound care system (BWCS)," a combination of wound blotting as a point-of-care testing and ultrasonic debridement, for promoting wound healing. Firstly, the cross-sectional study was conducted to examine the proportion of biofilm removal by ultrasonic debridement in pressure ulcers [Study 1]. Subsequently, the retrospective cohort study was conducted to examine the effectiveness of BWCS for healing of chronic wounds [Study 2]. The proportions of wound healing between wounds treated with BWCS and those with standard care in the home-visiting clinic were compared by Kaplan-Meier curve, and the Cox proportional hazard modeling was used to assess the effect of BWCS on wound healing. In Study 1, the median of biofilm removal proportion was 38.9% (interquartile range, 12.9-68.0%) for pressure ulcers treated with standard care and 65.2% (41.1-78.8%) for those treated with ultrasonic debridement (p = 0.009). In Study 2, the proportion of wound healing within 90 days was significantly higher in wounds treated with BWCS than in those treated with standard care (p = 0.001). The adjusted hazard ratio of BWCS for wound healing was 4.5 (95% confidence interval, 1.3-15.0; p = 0.015). In conclusion, we demonstrated that our novel approach, BWCS, can be a promising therapeutic strategy for visualizing biofilms that are not accompanied by necrotic tissue and promoting healing in chronic wounds.

The effect of 22.5 kHz low-frequency contact ultrasound debridement (LFCUD) on lower extremity wound healing for a vascular surgery population: A randomised controlled trial

The aim of this study was to compare changes in wound size and appearance and health complication rates in patients with vasculopathy and lower-extremity wounds treated with or without low-frequency contact ultrasound debridement (LFCUD) This study was a randomised controlled trial. The study was conducted in a vascular surgery service, including outpatient wound clinic and inpatient ward, in a tertiary care academic centre. In total, 70 patients with vasculopathy and lower-extremity wounds of mixed aetiology were enrolled in the trial; 68 completed the study. Patients were randomised to receive LFCUD plus usual care (n = 33) or usual care (n = 37) at 4 weekly visits, and were followed thereafter for up to 12 wk. The main outcome measures included closed wounds, change in wound surface area (WSA), and wound appearance by the revised Photographic Wound Assessment Tool (revPWAT). After 4 weekly LFCUD treatments, patients in the LFCUD group had significantly better wound appearance (total revPWAT score) compared with the control group treated only with usual care (P = <0.05). LFCUD-treated wounds also had a significant reduction in WSA over 4 wk that was not found in the UC group. LFCUD treatment was also associated with a greater number of healed wounds, odds ratio 5.00 (95% CI 1.24-20.25), and fewer instances of wound deterioration. Weekly LFCUD applications to patients with significant vasculopathy resulted in superior healing outcomes when compared with current usual wound care practice.

Low-Frequency Ultrasound Debridement in Chronic Wound Healing: A Systematic Review of Current Evidence

Chronic wounds are painful and debilitating to patients, pose a clinical challenge to physicians, and impose financial burden on the health-care system. New treatment options are therefore highly sought after. Ultrasound debridement is a promising technology that functions to disperse bacterial biofilms and stimulate wound healing. In this review, we focus on low-frequency ultrasound (20-60 kHz) and summarize the findings of 25 recent studies examining ultrasound efficacy. Ultrasound debridement appears to be most effective when used 3 times a week and has the potential to decrease exudate and slough, decrease patient pain, disperse biofilms, and increase healing in wounds of various etiology. Although current studies are generally of smaller size, the results are promising and we recommend the testing of low-frequency ultrasound therapy in clinical practice on a larger scale.

[Surgical treatment of the Charcot foot : long-term results and systematic review]

BACKGROUND

Because of extensive bone loss and the associated complex instability and deformity of the feet, Charcot arthropathy or neuroosteoarthropathy is a challenge for the orthopedic surgeon. Ulcerations offer entry of various bacteria; thus, infections are a frequent serious issue and complication. The careful choice of treatment is not only very important for the correct alignment of the foot and the loading capacity, but also contributes significantly to the prevention of skin irritation or the healing of existing ulcers. Above all, chronic plantar ulcerations, caused by prominent exostoses or axial malalignments are almost untreatable without surgery. Because diagnosis requires an individual approach, no strict regimen of therapy has become established.

OBJECTIVES

The major objective was to reduce the number of ulcerations and infections, and to minimize the risk of amputation. In addition, complications and comorbidities were determined. Tibio-calcaneal arthrodesis is a very frequently used surgical treatment option. Therefore, a special focus in the following article is on this method.

MATERIALS AND METHODS

In a 12-year period (1999-2011), 43 patients (46 feet) suffering from Charcot foot were treated surgically. The following were used: triple, talo-navicular, subtalar, tibio-calcaneal arthrodesis and midfoot fusion bolts. The arthrodesis related to the hindfoot and tarsus and most commonly the tibio-calcaneal arthrodesis was applied. The reduction of load on the affected foot preoperatively and postoperatively by white-cast, Aircast walker shoe or other orthesis is essential in the treatment. For a long-term satisfactory outcome, an orthopedic custom-made shoe is indispensable after surgical treatment.

RESULTS

After surgical treatment of 16 feet with ulcerations, 14 could be healed and only 2 suffered from complications, such as infections, nonunions, talus necrosis, and wound healing disorder. Revision was frequently necessary, although the majority of complications could be treated. In this population, three amputations could not be prevented.

CONCLUSION

Even with strict aseptic techniques and years of experience in Charcot arthropathy, complications can occur, which can even lead to amputation. The early detection of the Charcot foot is the most important factor and helps to reduce morbidity and further complications. Co-morbid diseases (e.g., diabetes mellitus) need special care and optimal treatment, because they are often responsible for the poor surgical outcome. Finally, the ulceration rate and related complications, such as amputation, can be reduced by timely surgical treatment. Unfortunately, the progressive course of the disease often requires follow-up operations.

Chronic wound repair and healing in older adults: current status and future research

Older adults are more likely to have chronic wounds than younger people, and the effect of chronic wounds on quality of life is particularly profound in this population. Wound healing slows with age, but the basic biology underlying chronic wounds and the influence of age-associated changes on wound healing are poorly understood. Most studies have used in vitro approaches and various animal models, but observed changes translate poorly to human healing conditions. The effect of age and accompanying multimorbidity on the effectiveness of existing and emerging treatment approaches for chronic wounds is also unknown, and older adults tend to be excluded from randomized clinical trials. Poorly defined outcomes and variables; lack of standardization in data collection; and variations in the definition, measurement, and treatment of wounds also hamper clinical studies. The Association of Specialty Professors, in conjunction with the National Institute on Aging and the Wound Healing Society, held a workshop, summarized in this article, to explore the current state of knowledge and research challenges, engage investigators across disciplines, and identify research questions to guide future study of age-associated changes in chronic wound healing.

Chronic wound repair and healing in older adults: current status and future research

The incidence of chronic wounds is increased among older adults, and the impact of chronic wounds on quality of life is particularly profound in this population. It is well established that wound healing slows with age. However, the basic biology underlying chronic wounds and the influence of age-associated changes on wound healing are poorly understood. Most studies have used in vitro approaches and various animal models, but observed changes translate poorly to human healing conditions. The impact of age and accompanying multi-morbidity on the effectiveness of existing and emerging treatment approaches for chronic wounds is also unknown, and older adults tend to be excluded from randomized clinical trials. Poorly defined outcomes and variables, lack of standardization in data collection, and variations in the definition, measurement, and treatment of wounds also hamper clinical studies. The Association of Specialty Professors, in conjunction with the National Institute on Aging and the Wound Healing Society, held a workshop, summarized in this paper, to explore the current state of knowledge and research challenges, engage investigators across disciplines, and identify key research questions to guide future study of age-associated changes in chronic wound healing.

Wound care in venous ulcers

Wound dressings: ulcer dressings should create and maintain a moist environment on the ulcer surface. It has been shown that in an ulcer with a hard crust and desiccated bed, the healing process is significantly slowed and sometimes completely blocked so favouring infection, inflammation and pain. In contrast a moist environment promotes autolytic debridement, angiogenesis and the more rapid formation of granulation tissue, favours keratinocytes migration and accelerates healing of wounds. Apart from these common characteristics, wound dressings are completely different in other aspects and must be used according to the ulcer stage. In necrotic ulcers, autolytic debridement by means of hydrogel and hydrocolloids or with enzymatic paste is preferred. In case of largely exuding wounds alginate or hydrofibre are indicated. When bleeding occurs alginate is indicated due to its haemostatic power. Where ulcers are covered by granulation tissue, polyurethane foams are preferred. When infection coexists antiseptics are necessary: dressing containing silver or iodine with large antibacterial spectrum have proved to be very effective. In the epithelization stage polyurethane films or membranes, thin hydrocolloids or collagen based dressings are very useful to favour advancement of the healing wound edge. Despite these considerations, a Cochrane review failed to find advantages for any dressing type compared with low-adherent dressings applied beneath compression. Surgical debridement and grafting of wounds, negative wound pressure treatment: surgical and hydrosurgical debridement are indicated in large, necrotic and infected wounds as these treatments are able to get rid of necrotic, infected tissue very quickly in a single surgical session, thereby significantly accelerating wound bed preparation and healing time. Negative wound pressure treatment creating a negative pressure on ulcer bed is able to favour granulation tissue and shorten healing time. In case of hard-to-heal leg ulcers such as large, deep, infected and long-lasting venous ulcers, sharp debridement and skin grafting may favour and shorten ulcer healing.

Observer bias in randomized clinical trials with measurement scale outcomes: a systematic review of trials with both blinded and nonblinded assessors

BACKGROUND

Clinical trials are commonly done without blinded outcome assessors despite the risk of bias. We wanted to evaluate the effect of nonblinded outcome assessment on estimated effects in randomized clinical trials with outcomes that involved subjective measurement scales.

METHODS

We conducted a systematic review of randomized clinical trials with both blinded and nonblinded assessment of the same measurement scale outcome. We searched PubMed, EMBASE, PsycINFO, CINAHL, Cochrane Central Register of Controlled Trials, HighWire Press and Google Scholar for relevant studies. Two investigators agreed on the inclusion of trials and the outcome scale. For each trial, we calculated the difference in effect size (i.e., standardized mean difference between nonblinded and blinded assessments). A difference in effect size of less than 0 suggested that nonblinded assessors generated more optimistic estimates of effect. We pooled the differences in effect size using inverse variance random-effects meta-analysis and used metaregression to identify potential reasons for variation.

RESULTS

We included 24 trials in our review. The main meta-analysis included 16 trials (involving 2854 patients) with subjective outcomes. The estimated treatment effect was more beneficial when based on nonblinded assessors (pooled difference in effect size -0.23 [95% confidence interval (CI) -0.40 to -0.06]). In relative terms, nonblinded assessors exaggerated the pooled effect size by 68% (95% CI 14% to 230%). Heterogeneity was moderate (I(2) = 46%, p = 0.02) and unexplained by metaregression.

INTERPRETATION

We provide empirical evidence for observer bias in randomized clinical trials with subjective measurement scale outcomes. A failure to blind assessors of outcomes in such trials results in a high risk of substantial bias.

[Joint infections. Known facts and new trends]

Acute septic arthritis is a surgical emergency because rapid septic destruction of articular cartilage can lead to impairment or even loss of joint function. Diagnosis consists of patient history, clinical examination, laboratory results, (sonography- guided) joint aspiration and radiography. Emergency therapy is based on arthroscopic or open joint debridement and lavage combined with systemic antibiotic therapy. No data are available for the recommendation of local antibiotics but antiseptic solutions are not recommended because of cartilage damage. New trends in diagnostics are positron emission tomography/computed tomography (PET/CT), urine sticks for analysis of joint fluid and molecular pathology. Chronic joint empyema is more diagnostically demanding and is difficult to treat. In cases of necrotic and infected articular cartilage, joint resection has to be performed for quiescence of infection. Options following successful treatment of empyema are arthroplasty, arthrodesis or permanent resection.

Low-frequency pulsed ultrasound in the nasal cavity and paranasal sinuses: a feasibility and distribution study

BACKGROUND

Bacterial biofilms have been implicated in refractory rhinosinusitis. Biofilms have been shown to respond to treatment with low-frequency ultrasound (LFU) therapy in vitro, and exposure to LFU has shown efficacy in wound repair and topical drug delivery in other fields. This preliminary study was designed to evaluate the safety and feasibility of LFU for use in the nasal cavity and paranasal sinuses.

METHODS

This was an experimental observational study. Six cadaver heads were used to deliver a mixture of Renografin and methylene blue solvent to the paranasal sinuses via LFU both before and after resident endoscopic sinus dissection. Sinus computed tomography (CT) scans of the cadaver heads were performed before and after mixture delivery, and blinded assessments were made for distribution to individual sinuses. Mucosa was harvested from 2 subsites to evaluate LFU-treated cadaver tissue.

RESULTS

Predissection, LFU delivered solution to 12 of 12 inferior and middle turbinates, 6 of 12 of the superior turbinates and ethmoid sinuses, and 1 of 12 maxillary sinuses as shown by contrast radiography. Postdissection, all heads showed delivery to the maxillary and sphenoid sinuses, with 8 of 12 sinus cavities showing delivery to the ethmoid region, and 4 of 11 to the frontal recess. Using hematoxylin and eosin (H&E) staining of tissue frozen sections, harvested tissue demonstrated no architectural damage to the mucosal layer from LFU exposure.

CONCLUSION

LFU appears to be capable of reliably delivering topical solution to the turbinates and ethmoid region preoperatively and to all sinuses, except the frontal, postoperatively. The nasal epithelium does not appear to be disrupted histologically from LFU at this time and distance. This data provides a foundation for a prospective human protocol studying the efficacy of this modality in the treatment of patients with chronic rhinosinusitis and biofilm formation.