Low-frequency pulsed ultrasound in the nasal cavity and paranasal sinuses: a feasibility and distribution study.
ABSTRACT 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.
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.
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.
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.
- International Forum of Allergy and Rhinology 07/2012; 2(4):269-70. · 1.00 Impact Factor
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ABSTRACT: The infection of orthopedic implantation devices with Staphylococcus is a serious concern within the biomaterial community. Treatments are not always successful because of antibiotic-resistant bacteria and serious biofilm infections. Human β-defensin 3 (hBD-3) is considered to be the most promising class of defensin antimicrobial peptides and its effect on antibiotic-resistant Staphylococcus biofilms, combined with ultrasound (US)-targeted microbubble (MB) destruction (UTMD), has not been reported. In the study, we found that biofilm densities, the percentage of live cells and the viable counts of two tested Staphylococcus recovered from the biofilm were significantly decreased in the maximum concentration hBD-3 combined with UTMD compared with those of any other groups. Furthermore, results suggested that UTMD could also enhance 1MIC hBD-3 activity inhibiting the biofilm-associated genes expression of icaAD and the methicillin-resistance genes expression of MecA by simultaneously promoting the icaR expression. UTMD may have great potential for improving antibiotic activity against biofilm infections.Inflammation 03/2013; · 1.92 Impact Factor
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ABSTRACT: Chronic rhinosinusitis (CRS) is a chronic infective, inflammatory upper respiratory disease. While the current medical treatment of CRS focuses on the systemic and topical use of steroids and/or antibiotics, many bacteria residing on mucosal surfaces of patients with CRS exist in a biofilm state, making them resistant to most systemic antibiotics. Alternative therapeutic strategies that include blocking bacterial molecular communication, inhibiting biofilm matrix production and breaking down bacterial biofilms are all being explored. Physical therapies such as therapeutic ultrasound (US) have been advocated and utilized as a treatment modality for CRS for many years. US may have antiinflammatory actions and can also be used for the local delivery of drugs through the skin. Therapeutic US, which has been shown in clinical studies to be an effective treatment for both acute rhinosinusitis and CRS, offers significant potential in CRS management.Current Infectious Disease Reports 03/2014; 16(3):398.