Geographic Distribution of Facial Plastic and Reconstructive Surgeons.

Background: Distribution of the general otolaryngology workforce has been described, but not specifically for the facial plastic and reconstructive surgeon (FPRS) workforce. Objective: To describe the distribution of FPRS within the United States. Methods: The 2022 American Academy of Facial Plastic and Reconstructive Surgery (AAFPRS) registry was used to identify active FPRSs. Member addresses were converted into coordinates and overlayed onto a geographic representation of 2020 census data within ArcGIS software. A centroid model of U.S. counties was constructed to determine the average distances residents were from the nearest FPRS. Results: In total, 1312 AAFPRS active members practiced in 373 counties. Thirty-three percent of all residents (115 million) resided in counties without an FPRS and 15.3% of FPRSs practiced in New York City or the Greater Los Angeles Area, which accounted for 8% of the total U.S. population. The mean and median distances a resident in a county without an FPRS was from the nearest FPRS are 63 and 49 miles (101 and 79 kilometers), respectively. Conclusions: Metropolitan areas have greater concentrations of FPRSs than the national average and the distances U.S. residents are from FPRS services are quantifiable.

Effects of Essential Oils on Scars and Wound Healing: A Systematic Review.

Essential oils (EOs) have been considered as a potential alternative therapy for wound healing and scar reduction. The aim of this article was to provide a comprehensive review examining the effects of EOs on wound healing and scars. PubMed, Cochrane, Ovid, and Embase computerized searches were performed through June 2020. Two independent reviewers conducted data extraction, with search results reviewed by the senior author following the PRISMA protocol. Three manuscripts examining three different EO-containing topical agents were analyzed. Outcomes include healing rate, erythema, pain, pruritus, patient discomfort, physician satisfaction, percent wound reduction, wound/scar surface perimeter area, and qualitative dermatological evaluation. All articles concluded that the EO-containing topical agents resulted in either superior or noninferior outcomes in comparison with controls. Hypericum-Calendula oil obtained lower wound surface perimeter area. Erythema (p = 0.001) was significantly decreased by the peppermint EO-containing topical agent. Physicians also reported greater satisfaction (p < 0.001) in wound appearance with use of the peppermint EO-containing topical agent. A paucity of studies have examined EO use for wound healing and scar reduction. Treatment with EO-containing topical agents resulted in decreased erythema with increased physician satisfaction of wound appearance. Future studies should assess what level of purity is needed for improved results and which EO, or combination of EOs, is most beneficial.

A multi-institutional study evaluating and describing atypical parathyroid tumors discovered after parathyroidectomy.

Objective: To describe common intraoperative and pathologic findings of atypical parathyroid tumors (APTs) and evaluate clinical outcomes in patients undergoing parathyroidectomy. Methods: In this multi-institutional retrospective case series, data were collected from patients who underwent parathyroidectomy from 2000 to 2018 from three tertiary care institutions. APTs were defined according to the AJCC eighth edition guidelines and retrospective chart review was performed to evaluate the incidence of recurrent laryngeal nerve injury, recurrence of disease, and disease-specific mortality. Results: Twenty-eight patients were identified with a histopathologic diagnosis of atypical tumor. Mean age was 56 years (range, 23-83) and 68% (19/28) were female. All patients had an initial diagnosis of primary hyperparathyroidism with 21% (6/28) exhibiting clinical loss of bone density and 32% (9/28) presenting with nephrolithiasis or renal dysfunction. Intraoperatively, 29% (8/28) required thyroid lobectomy, 29% (8/28) had gross adherence to adjacent structures and 46% (13/28) had RLN adherence. The most common pathologic finding was fibrosis 46% (13/28). Postoperative complications include RLN paresis/paralysis in 14% (4/28) and hungry bone syndrome in 7% (2/28). No patients with a diagnosis of atypical tumor developed recurrent disease, however there was one patient that had persistent disease and hypercalcemia that is being observed. There were 96% (27/28) patients alive at last follow-up, with one death unrelated to disease. Conclusion: Despite the new AJCC categorization of atypical tumors staged as Tis, we observed no recurrence of disease after resection and no disease-specific mortality. However, patients with atypical tumors may be at increased risk for recurrent laryngeal nerve injury and incomplete resection.

Estrogen receptor-positive adenocarcinoma of the cervix presenting during pregnancy: Two case reports and review of the literature.

The incidence of adenocarcinoma of the cervix in pregnancy is exceptionally rare, and thus there is no consensus on its management. Here, we report two cases of adenocarcinoma of the cervix diagnosed in the context of pregnancy. In our first case, a patient referred to colposcopy for atypical glandular cells of undetermined significance was subsequently diagnosed with well differentiated endocervical adenocarcinoma on cone biopsy. Just prior to the cone biopsy, she was incidentally found to have a first trimester pregnancy loss. The patient subsequently underwent a radical hysterectomy and bilateral sentinel lymph node dissection. Final pathology revealed a stage 1B1 (FIGO 2009) well differentiated adenocarcinoma of the cervix. Interestingly, the tumour was positive for estrogen receptor, which is unusual for cervical adenocarcinoma. In our second case, a patient presented with a pedunculated, exophytic cervical neoplasm at 31 weeks GA with self-limiting antepartum hemorrhage. The primary lesion measured 52 mm in diameter on MRI and was amputated at the base during the patient's elective repeat cesarean section. Final pathology revealed a stage IB2 (FIGO 2009) mucinous adenocarcinoma of the cervix. The patient subsequently underwent a radical hysterectomy and bilateral pelvic lymph node dissection 17 weeks after initial presentation. The depth of invasion was 2.2 mm, restricted to the inner third of the cervical wall, and there was no lymphovascular space invasion in the surgical specimen. Surgical margins, parametria, and lymph nodes were all negative for adenocarcinoma. This tumour was also found to be estrogen receptor/progesterone receptor (ER/PR) positive, again unusual for cervical adenocarcinoma. P16 was strongly positive and HPV DNA studies were also positive for human papilloma virus 18. The patient received adjuvant external beam radiotherapy to the pelvis and currently remains in remission.

A Report on the Use of Telehealth in Otolaryngology in the Pre COVID-19 Era.

Objective: To investigate the integration of and barriers to the utilization of telehealth technology and its components (telemedicine, e-Health, m-health) in daily otolaryngologic practice before the SARS CoV-2 (COVID-19) pandemic. Methods: This cross-sectional study was conducted at a tertiary academic center. A national survey of members of the American Academy of Otolaryngology-Head and Neck Surgery was administered. Descriptive analyses were performed to determine how telehealth was employed in otolaryngologists' practices. Results: A total of 184 surveys were completed. Telehealth technology was used by 50% of otolaryngologists surveyed. Regions with the largest percentage of physicians using telehealth were the Mid-Atlantic region (84%) and West Coast (67%). Most otolaryngologists indicated that they were familiar with telehealth or any of its components and how it is used in practice (52-83%), they had heard of telehealth or any of its components but were unsure what the terms specifically entailed (17-42%); 53% were satisfied with their current use of telehealth and electronic medical record (EMR); and 72% were comfortable utilizing smart devices for patient care. Most otolaryngologists (65%) indicated reimbursement as the biggest limitation to implementing telehealth, and 67% believed that typing was a hindrance to EMR utility. Conclusion: Half of the surveyed otolaryngologists used some form of telehealth at the time of the survey. The most commonly cited obstacle to physician adoption of telehealth was reimbursement. Although the adoption of telehealth technology was still limited in the field of otolaryngology based on this study, we are now seeing significant change due to the COVID-19 pandemic.

Location Propensity for Keloids in the Head and Neck.

Importance: The difficulty associated with concealing keloids located in the face and neck regions often results in disfigurement and psychological stress for patients. Objective: The purpose of this review is to determine if specific regions on the head and neck have a greater propensity to develop keloids to alert the facial plastic surgeon of regional keloid risk. Evidence Review: PubMed, Ovid, Cochrane, and Embase computerized searches were performed through January 2020. Two independent reviewers conducted data extraction following a predetermined protocol identifying 1445 keloid studies. Findings: The prevalence of keloids in different regions of the head and neck was evaluated among 1598 head and neck keloids in the final analysis. Three of nine studies evaluated keloids specific to the ear and described a combined 1194 ear keloids locations (53.0% lobule, 22.9% cartilaginous region, 0.3% both, and 23.7% unspecified). One study reported exclusively on 82 neck keloids 72% of which were located in the submental or submandibular region. The remaining five studies evaluated 322 head and neck keloids more generally and showed 70.2% ear, 9.6% unspecified, 6.5% peri-/postauricular, 5.6% beard area, 2.2% scalp/forehead, 2.2% chin, 1.6% lateral face, 1.6% neck, and 0.3% central face keloids. Conclusions and Relevance: The ear, periauricular regions, bearded facial regions, and submandibular and submental sites show the highest propensity for keloid development in the head and neck region. The lowest keloid risk occurred in the central face region. Risk factors in relation to facial and neck regions associated with the formation of keloids should be taken into consideration before performing elective procedures in keloid susceptible individuals.

Sinonasal pathophysiology of SARS-CoV-2 and COVID-19: A systematic review of the current evidence.

OBJECTIVE: The ongoing pandemic of coronavirus disease (2019 coronavirus disease [COVID-19]), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus, is highly contagious with high morbidity and mortality. The role of the nasal and paranasal sinus cavities is increasingly recognized for COVID-19 symptomatology and transmission. We therefore conducted a systematic review, synthesizing existing scientific evidence about sinonasal pathophysiology in COVID-19. STUDY DESIGN: Systematic review. METHODS: Systematic searches were performed of all indexed studies in PubMed/Medline and Cochrane databases through 28 March 2020 and studies searchable on preprints.com (including ArXiv and Scilit repositories) through 30 March 2020. Data extraction focused on sinonasal pathophysiology in COVID-19. RESULTS: A total of 19 studies were identified. The sinonasal cavity may be a major site of infection by SARS-CoV-2, where susceptibility genes required for infection are expressed at high levels and may be modulated by environmental and host factors. Viral shedding appears to be highest from the nose, therefore reflecting a major source for transmission. This has been highlighted by multiple reports of health care-associated infection (HAI) during rhinologic procedures, which are now consequently considered to be high risk for SARS-CoV-2 transmission to health care workers. While sinonasal symptomatology, such as rhinorrhea or congestion, appears to be a rarer symptom of COVID-19, anosmia without nasal obstruction is reported as highly specific predictor of COVID-19+ patients. CONCLUSION: Sinonasal pathophysiology is increasingly important in our understanding of COVID-19. The sinonasal tract may be an important site of infection while sinonasal viral shedding may be an important transmission mechanism-including HAI. Anosmia without nasal obstruction may be a highly specific indicator of COVID-19. LEVEL OF EVIDENCE: 2a.

Association of the sinonasal bacterial microbiome with clinical outcomes in chronic rhinosinusitis: a systematic review.

BACKGROUND: The association between sinonasal microbiome and clinical outcomes of patients with chronic rhinosinusitis (CRS) is unclear. We performed a systematic review of prior studies evaluating the CRS microbiome in relation to clinical outcomes. METHODS: Computerized searches of PubMed/Medline, Cochrane, and EMBASE were updated through October 2019 revealing a total of 9 studies including 244 CRS patients. A systematic review of the literature was performed, including data extraction focusing on sample region, sequencing platforms, predominant organisms, and outcomes measures. RESULTS: Nine criterion-meeting studies included 244 CRS patients, with varied results. Eight studies used 16s-ribosomal RNA (16s-rRNA) gene sequencing to assess the sinonasal microbiome and 1 used 16s-rRNA PhyloChip analysis. Seven studies used Sino-Nasal Outcome Test scores, 1 applied another CRS symptom metric, and 1 used need for additional procedures/antibiotics as the primary clinical outcome. Three studies suggest that baseline abundance of phylum Actinobacteria (specifically genus Corynebacterium) was predictive of better surgical outcome. One study found C. tuberculostearicum was positively correlated with symptom severity. Another study revealed genus Escherichia was overrepresented in CRS and had positive correlation with increased symptom scores. In addition, 1 study identified Acinetobacter johnsonii to be associated with improvement in symptom scores while supporting Pseudomonas aeruginosa as having a negative impact on quality of life. CONCLUSION: Microbiome data are varied in their association with clinical outcomes of CRS patients. Further research is required to identify if predominance of certain microbes within the microbiome is predictive of CRS patients' outcomes.

Competitiveness of Otolaryngology Residency Applicants without a Home Program.

PURPOSE: Investigate if otolaryngology residency home programs (HP) are associated with advantages in National Resident Matching Program match compared to applicants without HPs. METHODS: Surveys were distributed to fourth-year medical students applying to otolaryngology residency (2015-2016 cycle) via OHNS (2015-2016) Applicants Closed Facebook Page and Otomatch. Applicant data analyzed included HP, United States Medical Licensing Examination (USMLE) scores, number of away rotations, and matching at top choice. RESULTS: Applicants were grouped: (1) HP, (2) no HP but have ENT staff (staff), and (3) no HP or staff (none). Ninety-five percent of survey participants matched into otolaryngology (n = 62). A sub-analysis of match preference among matching applicants revealed 63% of participants with HP matched to their first choice compared to 56% (staff) and 14% (none) (P = .058). Match rate between those with any staff (HP or staff) versus those without was statistically significant (P = .037). Applicants without HPs went on more away rotations than students with HPs (mean: 2.5 ± 0.5 vs 1.7 ± 0.07, P = .0002). No statistical significance was seen between applicants with/without HP in regards to USMLE scores, publications, or number of interviews. CONCLUSION: Applicants applying to otolaryngology residency without HPs are as competitive as those who have HPs. However, without HPs, applicants tend to participate in more away rotations and are less likely to match at their top choice.

Are Standardized Letters of Recommendation in Residency Applications Correlated With Objective Data?

OBJECTIVE: To evaluate whether the standardized letter of recommendation (SLOR), commonly used for medical students applying to otolaryngology residency, correlates with objective data in the application. BACKGROUND: Standardized letters of recommendation using Likert-type scales for different attributes are commonly used by evaluators because of their high interrater reliability and efficiency in preparation and interpretation. Given that these are subjectively scored, it is unknown how well these correlate with objective data. METHODS: Applications to the University of Cincinnati otolaryngology residency were evaluated in the academic cycle of 2017-2018. Standardized letters of recommendation were scored to determine whether certain attributes were correlated with objective data (United States Medical Licensing Examination [USMLE] scores and number of presentations/publications) provided in their application. Spearman correlations were used to evaluate the strength of the relationship between the subjective score in certain attributes with objective data. RESULTS: There were 217 applications to the University of Cincinnati that contained SLORs. Of these applications, 474 standardized letters were scored in categories of medical knowledge, research, and commitment to academic medicine. Total publications and presentations were weakly correlated with commitment to academic medicine (0.35, P < .0001, n = 369) and with research (0.44, P < .0001, n = 355). Medical knowledge was weakly correlated with Step 1 scores (0.20, P < .0001) and Step 2 scores (0.18, P = .0002). CONCLUSIONS: Subjective research and commitment to academic medicine rating scores were weakly correlated with greater academic productivity. Similarly, medical knowledge scores were weakly correlated with Step 1/2 scores. Further research may be needed to assess how to interpret SLOR scores in addition to the information available in an otolaryngology application. LEVEL OF EVIDENCE: 4.

Feasibility of shotgun metagenomics to assess microbial ecology of pediatric tracheostomy tubes.

OBJECTIVE: Biofilm formation on medical devices such as tracheostomy tubes (TTs) is a serious problem. The clinical impact of biofilms on the airway is still unclear. Biofilms may play a role in granulation tissue development, recurrent airway infections, and failure of laryngotracheal reconstructions. The microbial ecology on TTs has yet to be elucidated. The purpose of this study was to determine the feasibility of shotgun metagenomics to assess the biodistribution of microorganisms on TTs. METHODS: Four TTs were collected from pediatric patients (1.4-10.2 years) with (n = 2) and without (n = 2) granulation tissue formation. Duration of TT placement prior to retrieval from patients ranged from 5 to 365 days. DNA extraction was performed using the MO BIO UltraClean Microbial Isolation (Mo Bio Laboratories, Carlsbad, CA). Library generation using Nextera XT adapters (Illumina Inc., San Diego, CA) and metagenomic shotgun sequencing was performed using the Illumina NextSeq500 (Illumina Inc, San Diego, CA). Salinibacter ruber, a species not found in mammalian microbiome communities, was used as a DNA standard and represented 0.7% to 5.7% of the microbiome, ensuring good quality and abundance of sample DNA. RESULTS: Metagenomic shotgun sequencing was successful for all patients. In TTs associated with granuloma, Fusobacterium nucleatum, Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae were predominant, most of which are considered pathogens. From TTs without granulomas, Neisseria mucosa, Neisseria sicca, Acinetobacter baumannii, and Haemophilus parainfluenzae were identified, primarily consistent with respiratory microbiome. CONCLUSION: This study reveals that metagenomic shotgun sequencing of biofilms formed on pediatric TTs is feasible with an apparent difference in microbiome for patients with granulation tissue. Further studies are necessary to elucidate the pathogenesis of microbial ecology and its role in airway disease in patients with TTs. LEVEL OF EVIDENCE: 2c Laryngoscope, 129:317-323, 2019.

Prospective observational case series evaluating middle ear fluid and tympanostomy tubes through pyrosequencing.

OBJECTIVE: One of the most common sequelae of tympanostomy tube (TT) placement is post-tympanostomy tube otorrhea (PTTO). Granulation tissue formation has been reported in 5-13.8% of patients with TT placement. The purpose of this study is to determine the biodistribution of microorganisms on TTs and middle ear fluid obtained from patients with PTTO. METHODS: This was a prospective observational study of subjects (6-months-16-years) who underwent standard of care treatment for chronic PTTO. Data was collected on diagnosis, existence of antibiotic resistance, duration of tube placement, and evidence of recurrent infection and/or PTTO. TTs and middle ear fluid were subjected to pyrosequencing; additionally, ear fluid samples were sent for culture-based laboratory diagnostics. RESULTS: DNA-pyrosequencing analysis of bacteria from fluid and TTs of pediatric subjects with PTTO revealed a mixture of both aerobic and anaerobic populations. Retained tubes with minimal otorrhea revealed a predominance of Staphylococcus species, normal external auditory canal (EAC) microbiome, within middle ear fluid as well as on TTs. However, TTs with active mucopurulent otorrhea and granulation tissue unveiled prominence of Gram-negative facultative anaerobes such as Pseudomonas and Eikenella. Discrepancies in prominent bacteria were seen between standard culture-based techniques versus pyrosequencing. CONCLUSION: Retained tympanostomy tubes are colonized primarily with normal flora of the EAC. However, mucopurulent otorrhea associated with granulation tissue formation revealed a prominence of Gram-negative facultative anaerobes. Standard culture-based diagnostics may identify bacteria, which are not predominant species of infection. Future studies are necessary to assess the association of Gram-negative facultative anaerobes with granulation tissue formation.

Granulomatosis with polyangiitis presenting as facial nerve palsy in a teenager.

Granulomatosis with polyangiitis (GPA, previously known as Wegener's granulomatosis) is an autoimmune systemic small-vessel vasculitis, associated with the presence of anti-neurophil cytoplasmic antibodies with a cytoplasmic staining pattern (c-ANCA). It is characterized by necrotizing granulomas, usually affecting the airways and kidneys. GPA should be considered when patients do not improve despite adequate treatment of otologic symptoms, when patients have unspecific symptoms suggesting systemic disease (e.g. fever, malaise), or when other organs are involved (kidney, lungs, etc.). We present an interesting case of a 14-year-old female with eight-weeks of bilateral otalgia, unilateral facial nerve palsy, decreased appetite, and fatigue refractory to steroid, anti-viral, and antibiotic treatment ultimately diagnosed with GPA.

Planktonic Growth of Pseudomonas aeruginosa around a Dual-Species Biofilm Supports the Growth of Fusobacterium nucleatum within That Biofilm.

PURPOSE: The goal of this study was to understand the potential interaction between Pseudomonas aeruginosa and Fusobacterium nucleatum within the middle ear. METHODS: We examined the microbiota of ear fluid and tympanostomy tubes (TTs) obtained from patients with posttympanostomy tube otorrhea. We also examined biofilms formed by P. aeruginosa and F. nucleatum, singly or together, under aerobic or anaerobic conditions. RESULTS: While the facultative anaerobe P. aeruginosa dominated the bacterial population within the ear fluid, strict anaerobes, including F. nucleatum, dominated bacterial populations within the TTs. F. nucleatum was able to grow under aerobic conditions only in the presence of P. aeruginosa, whose growth reduced the level of dissolved oxygen within the broth to nearly anoxic condition within 4 h after inoculation. The presence of P. aeruginosa allowed F. nucleatum to maintain its growth for 72 h within the dual-species biofilm but not within the planktonic growth. Visualization of the biofilms revealed coaggregation of P. aeruginosa and F. nucleatum. CONCLUSION: Extrapolation of these results suggests that, within the middle ear fluid, the growth of P. aeruginosa produces the anaerobic conditions required for the growth of F. nucleatum, both within effusion and within biofilms.

Syndromic Craniosynostosis.

Syndromic craniosynostosis affects up to 1:30,000 live births with characteristic craniofacial growth restrictions, deformities, and other associated abnormalities, such as carpal-pedal anomalies and cognitive function impairment. More than 150 syndromes are associated with craniosynostosis. This article describes some commonalities and distinguishing features and management of syndromic synostosis. Also addressed is secondary synostosis, which is often found in syndromic children with problems related to microcephaly, hydrocephalus, or shunt-induced craniosynostosis, although pathophysiologically and genetically different. The importance of obtaining a thorough history and a complete physical and examination is highlighted. Adjuvant testing and multidisciplinary management are discussed.

Direct Lymph Node Vaccination of Lentivector/Prostate-Specific Antigen is Safe and Generates Tissue-Specific Responses in Rhesus Macaques.

Anti-cancer immunotherapy is emerging from a nadir and demonstrating tangible benefits to patients. A variety of approaches are now employed. We are invoking antigen (Ag)-specific responses through direct injections of recombinant lentivectors (LVs) that encode sequences for tumor-associated antigens into multiple lymph nodes to optimize immune presentation/stimulation. Here we first demonstrate the effectiveness and antigen-specificity of this approach in mice challenged with prostate-specific antigen (PSA)-expressing tumor cells. Next we tested the safety and efficacy of this approach in two cohorts of rhesus macaques as a prelude to a clinical trial application. Our vector encodes the cDNA for rhesus macaque PSA and a rhesus macaque cell surface marker to facilitate vector titering and tracking. We utilized two independent injection schemas demarcated by the timing of LV administration. In both cohorts we observed marked tissue-specific responses as measured by clinical evaluations and magnetic resonance imaging of the prostate gland. Tissue-specific responses were sustained for up to six months-the end-point of the study. Control animals immunized against an irrelevant Ag were unaffected. We did not observe vector spread in test or control animals or perturbations of systemic immune parameters. This approach thus offers an "off-the-shelf" anti-cancer vaccine that could be made at large scale and injected into patients-even on an out-patient basis.

Image-guided surgery and craniofacial applications: mastering the unseen.

Image-guided surgery potentially enhances intraoperative safety and outcomes in a variety of craniomaxillofacial procedures. We explore the efficiency of one intraoperative navigation system in a single complex craniofacial case, review the initial and recurring costs, and estimate the added cost (e.g., additional setup time, registration). We discuss the potential challenges and benefits of utilizing image-guided surgery in our specific case and its benefits in terms of educational and teaching purposes and compare this with traditional osteotomies that rely on a surgeon's thorough understanding of anatomy coupled with tactile feedback to blindly guide the osteotome during surgery. A 13-year-old presented with untreated syndromic multi-suture synostosis, brachycephaly, severe exorbitism, and midface hypoplasia. For now, initial costs are high, recurring costs are relatively low, and there are perceived benefits of imaged-guided surgery as an excellent teaching tool for visualizing difficult and often unseen anatomy through computerized software and multi-planar real-time images.

The antimicrobial agent, Next-Science, inhibits the development of Staphylococcus aureus and Pseudomonas aeruginosa biofilms on tympanostomy tubes.

OBJECTIVE: The purpose of this study was to determine if the recently developed novel antimicrobial/antibiofilm agent Next-Science (NS) inhibits biofilm development by Staphylococcus aureus or Pseudomonas aeruginosa on tympanostomy tubes (TT) and to define the concentration of NS at which this inhibition occurs. METHODS: Preliminary titration experiments determined the effective concentrations of NS that completely inhibit the planktonic growth of S. aureus and P. aeruginosa. Since NS has the potential to inhibit both planktonic growth and biofilm development, we examined the antibiofilm effect using the established concentrations that inhibited planktonic growth. Biofilms developed on TT using the microtiter plate assay were assessed quantitatively by determining the number of microorganisms per tube (CFU/tube) and qualitatively by visualization with confocal laser scanning microscopy (CLSM). RESULTS: Planktonic growth of S. aureus and P. aeruginosa was inhibited by 20.3 µg/mL and 325 µg/mL of NS, respectively. While S. aureus and P. aeruginosa formed well-developed biofilms on TT at 24 h without treatment, addition of the indicated concentrations of NS at the time of inoculation of the TT inhibited the formation of biofilms by both organisms. CLSM confirmed the absence of biofilms on either the inner or outer surface of the treated TTs. At 8 h post-inoculation, P. aeruginosa formed a partial biofilm on the TT when untreated. In comparison, the NS-treated biofilms failed to develop further and the CFU/TT were significantly reduced. CONCLUSION: The novel antimicrobial agent NS inhibited the development of S. aureus and P. aeruginosa biofilms on TTs. The same concentrations of NS inhibited both planktonic growth and biofilm development.