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1.
Front Pediatr ; 12: 1365767, 2024.
Article in English | MEDLINE | ID: mdl-38415207

ABSTRACT

In this study we combined non-invasive transcutaneous auricular vagal nerve stimulation (taVNS) with 40 h of constraint induced movement therapy (CIMT) in infants. All infants completed the full intervention with no adverse events. Therapists were able to maintain high treatment fidelity and reported high ratings for ease of use and child tolerance. Preliminary results show promising gains on motor outcomes: Mean QUEST increase 19.17 (minimal clinically important difference, MCID 4.89); Mean GMFM increase 13.33 (MCID 1%-3%). Infants also exceeded expectations on Goal Attainment Scores (+1). Early data is promising that taVNS paired with intensive motor CIMT is feasible, reliable, and safe in young infants with hemiplegia, and may help harness activity-dependent plasticity to enhance functional movement.

2.
Otol Neurotol ; 44(8): 817-821, 2023 09 01.
Article in English | MEDLINE | ID: mdl-37442597

ABSTRACT

OBJECTIVE: We reviewed a cohort of patients with untreated sporadic vestibular schwannoma (VS) and examined the relationship between high-frequency hearing loss (HFHL) in the non-VS ear and long-term hearing outcomes in the VS-affected ear. We hypothesized that the progression of HFHL is associated with accelerated hearing decline in sporadic VS. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary center. PATIENTS: We studied 102 patients with sporadic VS diagnosed from 1999 to 2015 with ≥5 years of observation (median, 6.92; interquartile range, 5.85-9.29). Sixty-six patients had AAO-HNS class A/B hearing at presentation and were included in analysis. INTERVENTIONS: Audiometry, serial magnetic resonance imaging for observation of VS. MAIN OUTCOME MEASURES: Four-frequency pure tone average (PTA) and word recognition scores (WRS) in the VS-affected ear. Decline in high-frequency PTA (average of thresholds at 4000, 6000, and 8,000 Hz) was defined as ≥10 dB during the study period. Decline in WRS was defined as ≥10%. RESULTS: Compared with those without, patients with progressive HFHL in the non-VS ear were more likely to experience a decline in WRS in the VS ear (80% vs. 54%, p = 0.031). However, the same group showed no difference (52% vs. 41%, p = 0.40) in decline in PTA of the VS ear. CONCLUSIONS: Patients with observed VS who experience progressive HFHL in the non-VS ear are more likely to experience significant declines in speech understanding in the VS-affected ear over time. Patients with a history of presbycusis may have an increased risk of losing serviceable hearing because of sporadic VS.


Subject(s)
Neuroma, Acoustic , Presbycusis , Humans , Neuroma, Acoustic/complications , Presbycusis/epidemiology , Retrospective Studies , Treatment Outcome , Hearing , Audiometry, Pure-Tone
3.
J Med Entomol ; 59(2): 784-787, 2022 03 16.
Article in English | MEDLINE | ID: mdl-35041004

ABSTRACT

The soft tick Carios kelleyi (Cooley and Kohls, 1941) is an ectoparasite of bats that can harbor bacteria known to cause disease in humans, such as Rickettsia spp., Bartonella spp., and relapsing fever Borrelia spp. Human-tick encounters may occur when bats occupy attics or similar dwellings with access points to human-inhabited areas. During May 2021, a partially engorged adult female C. kelleyi was collected from a Vermont home with an attic that was being used as a roost by big brown bats, Eptesicus fuscus (Chiroptera: Vespertilionidae). The source of the blood in the tick was the domestic dog, Canis lupus familiaris. Subsequently, eight C. kelleyi larvae were collected from a rescued E. fuscus adult. This is the first report of a soft tick species from Vermont and it is unknown how long C. kelleyi has been present in this state. Reports of C. kelleyi are on the rise across the northeastern United States but the implications for the health of humans, domestic animals, and bats in northern New England remain unclear. Bat management plans should consider the importance of bat exclusion in preventing tick encounters with members of the household and should include a tick monitoring component if bats are evicted.


Subject(s)
Acari , Argasidae , Chiroptera , Ticks , Animals , Chiroptera/parasitology , Dogs , Female , United States , Vermont
5.
PeerJ ; 9: e12313, 2021.
Article in English | MEDLINE | ID: mdl-34820166

ABSTRACT

Tick-borne diseases, such as those transmitted by the blacklegged tick Ixodes scapularis, are a significant and growing public health problem in the US. There is mounting evidence that co-occurring non-pathogenic microbes can also impact tick-borne disease transmission. Shotgun metagenome sequencing enables sampling of the complete tick hologenome-the collective genomes of the tick and all of the microbial species contained therein, whether pathogenic, commensal or symbiotic. This approach simultaneously uncovers taxonomic composition and allows the detection of intraspecific genetic variation, making it a useful tool to compare spatial differences across tick populations. We evaluated this approach by comparing hologenome data from two tick samples (N = 6 ticks per location) collected at a relatively fine spatial scale, approximately 23 km apart, within a single US county. Several intriguing variants in the data between the two sites were detected, including polymorphisms in both in the tick's own mitochondrial DNA and that of a rickettsial endosymbiont. The two samples were broadly similar in terms of the microbial species present, including multiple known tick-borne pathogens (Borrelia burgdorferi, Babesia microti, and Anaplasma phagocytophilum), filarial nematodes, and Wolbachia and Babesia species. We assembled the complete genome of the rickettsial endosymbiont (most likely Rickettsia buchneri) from both populations. Our results provide further evidence for the use of shotgun metagenome sequencing as a tool to compare tick hologenomes and differentiate tick populations across localized spatial scales.

6.
J Infect Dis ; 223(7): 1250-1259, 2021 04 08.
Article in English | MEDLINE | ID: mdl-32780860

ABSTRACT

BACKGROUND: It is not known whether reductions in socioeconomic and racial disparities in incidence of invasive pneumococcal disease (defined as the isolation of Streptococcus pneumoniae from a normally sterile body site) noted after pneumococcal conjugate vaccine (PCV) introduction have been sustained. METHODS: Individual-level data collected from 20 Tennessee counties participating in Active Bacterial Core surveillance over 19 years were linked to neighborhood-level socioeconomic factors. Incidence rates were analyzed across 3 periods-pre-7-valent PCV (pre-PCV7; 1998-1999), pre-13-valent PCV (pre-PCV13; 2001-2009), and post-PCV13 (2011-2016)-by socioeconomic factors. RESULTS: A total of 8491 cases of invasive pneumococcal disease were identified. Incidence for invasive pneumococcal disease decreased from 22.9 (1998-1999) to 17.9 (2001-2009) to 12.7 (2011-2016) cases per 100 000 person-years. Post-PCV13 incidence (95% confidence interval [CI]) of PCV13-serotype disease in high- and low-poverty neighborhoods was 3.1 (2.7-3.5) and 1.4 (1.0-1.8), respectively, compared with pre-PCV7 incidence of 17.8 (15.7-19.9) and 6.4 (4.9-7.9). Before PCV introduction, incidence (95% CI) of PCV13-serotype disease was higher in blacks than whites (17.3 [15.1-19.5] vs 11.8 [10.6-13.0], respectively); after introduction, PCV13-type disease incidence was greatly reduced in both groups (white: 2.7 [2.4-3.0]; black: 2.2 [1.8-2.6]). CONCLUSIONS: Introduction of PCV13 was associated with substantial reductions in overall incidence and socioeconomic and racial disparities in PCV13-serotype incidence.


Subject(s)
Healthcare Disparities , Pneumococcal Infections , Pneumococcal Vaccines/administration & dosage , Race Factors , Socioeconomic Factors , Humans , Incidence , Pneumococcal Infections/epidemiology , Pneumococcal Infections/prevention & control , Poverty , Tennessee/epidemiology , Vaccines, Conjugate
7.
Infect Control Hosp Epidemiol ; 42(2): 139-141, 2021 02.
Article in English | MEDLINE | ID: mdl-32880246

ABSTRACT

OBJECTIVE: The Tennessee Department of Health (TDH) investigated a hepatitis A virus (HAV) outbreak to identify risk factors for infection and make prevention recommendations. DESIGN: Case series. SETTING: Community hospital. PARTICIPANTS: Healthcare workers (HCWs) or patients with laboratory-confirmed acute HAV infection during October 1, 2018-January 10, 2019. METHODS: HCWs with suspected or confirmed hepatitis A infections were interviewed to assess their exposures and activities. Patient medical records and hospital administrative records were reviewed to identify common exposures. We conducted a site investigation to assess knowledge of infection control practices among HCWs. Serum specimens from ill persons were tested for HAV RNA by polymerase chain reaction (PCR) and genotyped. RESULTS: We identified 6 HCWs and 2 patients with laboratory-confirmed HAV infection. All cases likely resulted from exposure to a homeless patient with a history of recreational substance use and undiagnosed HAV infection. Breaches in hand hygiene and use of standard precautions were identified. HAV RNA was detected in 7 serum specimens and all belonged to an identical strain of HAV genotype 1b. CONCLUSIONS: A hepatitis A outbreak among hospital patients and HCWs resulted from exposure to a single patient with undiagnosed HAV infection. Breakdowns in infection control practices contributed to the outbreak. The likelihood of nosocomial transmission can be reduced with proper hand hygiene, standard precautions, and routine disinfection. During community outbreaks, medical providers can better prevent ongoing transmission by including hepatitis A in the differential diagnosis among patients with a history of recreational substance use and homelessness.


Subject(s)
Cross Infection , Hepatitis A , Cross Infection/diagnosis , Cross Infection/epidemiology , Disease Outbreaks , Health Personnel , Hepatitis A/diagnosis , Hepatitis A/epidemiology , Hospitals, Community , Humans
8.
J Biomed Mater Res B Appl Biomater ; 109(3): 394-400, 2021 03.
Article in English | MEDLINE | ID: mdl-32830908

ABSTRACT

Auricular reconstruction is a technically demanding procedure requiring significant surgical expertise, as the current gold standard involves hand carving of the costal cartilage into an auricular framework and re-implantation of the tissue. 3D-printing presents a powerful tool that can reduce technical demands associated with the procedure. Our group compared clinical, radiological, histological, and biomechanical outcomes in single- and two-stage 3D-printed auricular tissue scaffolds in an athymic rodent model. Briefly, an external anatomic envelope of a human auricle was created using DICOM computed tomography (CT) images and modified in design to create a two-stage, lock-in-key base and elevating platform. Single- and two-stage scaffolds were 3D-printed by laser sintering poly-L-caprolactone (PCL) then implanted subcutaneously in five athymic rats each. Rats were monitored for ulcer formation, site infection, and scaffold distortion weekly, and scaffolds were explanted at 8 weeks with analysis using microCT and histologic staining. Nonlinear finite element analysis was performed to determine areas of high strain in relation to ulcer formation. Scaffolds demonstrated precise anatomic appearance and maintenance of integrity of both anterior and posterior auricular surfaces and scaffold projection, with no statistically significant differences in complications noted between the single- and two-staged implantation. While minor superficial ulcers occurred most commonly at the lateral and superior helix coincident with finite element predictions of high skin strains, evidence of robust tissue ingrowth and angiogenesis was visible grossly and histologically. This promising preclinical small animal model supports future initiatives for making clinically viable options for an ear tissue scaffold.


Subject(s)
Chondrocytes/metabolism , Ear Cartilage , Plastic Surgery Procedures , Printing, Three-Dimensional , Tissue Engineering , Tissue Scaffolds/chemistry , Animals , Ear Cartilage/chemistry , Ear Cartilage/metabolism , Rats , Rats, Nude
10.
J Infect Dis ; 222(Suppl 5): S442-S450, 2020 09 02.
Article in English | MEDLINE | ID: mdl-32877559

ABSTRACT

BACKGROUND: Injection drug use (IDU) is an established but uncommon risk factor for candidemia. Surveillance for candidemia is conducted in East Tennessee, an area heavily impacted by the opioid crisis and IDU. We evaluated IDU-associated candidemia to characterize the epidemiology and estimate the burden. METHODS: We assessed the proportion of candidemia cases related to IDU during January 1, 2014-September 30, 2018, estimated candidemia incidence in the overall population and among persons who inject drugs (PWID), and reviewed medical records to compare clinical features and outcomes among IDU-associated and non-IDU candidemia cases. RESULTS: The proportion of IDU-associated candidemia cases in East Tennessee increased from 6.1% in 2014 to 14.5% in 2018. Overall candidemia incidence in East Tennessee was 13.5/100 000, and incidence among PWID was 402-1895/100 000. Injection drug use-associated cases were younger (median age, 34.5 vs 60 years) and more frequently had endocarditis (39% vs 3%). All-cause 30-day mortality was 8% among IDU-associated cases versus 25% among non-IDU cases. CONCLUSIONS: A growing proportion of candidemia in East Tennessee is associated with IDU, posing an additional burden from the opioid crisis. The lower mortality among IDU-associated cases likely reflects in part the younger demographic; however, Candida endocarditis seen among approximately 40% underscores the seriousness of the infection and need for prevention.


Subject(s)
Candida/isolation & purification , Candidemia/epidemiology , Drug Users/statistics & numerical data , Endocarditis/epidemiology , Substance Abuse, Intravenous/complications , Adult , Age Factors , Candidemia/diagnosis , Candidemia/microbiology , Endocarditis/blood , Endocarditis/microbiology , Epidemiological Monitoring , Female , Hospital Mortality , Humans , Incidence , Male , Medical Records/statistics & numerical data , Risk Factors , Tennessee/epidemiology
11.
Eur Arch Otorhinolaryngol ; 277(7): 2085-2093, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32193723

ABSTRACT

PURPOSE: The incidence of oropharyngeal squamous cell carcinoma continues to rise with the majority of patients receiving definitive or adjunctive radiation. For patients with locoregional recurrence after radiation, optimal treatment involves salvage surgery. The aim of this study is to identify factors that predict survival to ultimately improve patient selection for salvage surgery. METHODS: Retrospective cohort study at an NCI-designated cancer center. We analyzed patients with a history of head and neck radiation who presented with persistent/recurrent or second primary disease requiring salvage oropharyngeal resection from 1998-2017 (n = 120). Patients were stratified into three classes based on time to recurrence and presence of laryngopharyngeal dysfunction. Primary outcomes were 5-year overall survival (OS) and disease specific survival (DSS). RESULTS: Median OS was 27 months (median follow-up 20 months). Five-year OS was 47% for class I (recurrence > 2 years), 26% for class II (recurrence ≤ 2 years), and 0% for class III (recurrence ≤ 2 years and laryngopharyngeal dysfunction), (p < 0.0001). Five-year DSS showed significant differences between classes (p < 0.0001). On multivariate analysis, class remained predictive of OS (p = 0.04- < 0.001) and DSS (p = 0.04-0.001). Adjuvant radiation after salvage surgery with negative margins showed superior OS (71% vs. 28%, p = 0.01) and DSS (83% vs 37%, p = 0.02) compared to surgery alone and was a significant predictor of improved survival on multivariate analysis (HR 0.1, p = 0.04). CONCLUSION: This study identified a subset of patients with oropharyngeal cancer recurrence within two years of initial treatment and with laryngopharyngeal dysfunction who have poor outcomes for salvage surgery.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Oropharyngeal Neoplasms , Carcinoma, Squamous Cell/radiotherapy , Carcinoma, Squamous Cell/surgery , Humans , Neoplasm Recurrence, Local/epidemiology , Neoplasm Recurrence, Local/surgery , Oropharyngeal Neoplasms/radiotherapy , Oropharyngeal Neoplasms/surgery , Retrospective Studies , Salvage Therapy , Survival Rate
12.
Public Health Rep ; 134(5): 537-541, 2019.
Article in English | MEDLINE | ID: mdl-31390300

ABSTRACT

OBJECTIVES: Between 2003 and 2013, the rate of neonatal abstinence syndrome (NAS)-a postnatal drug withdrawal syndrome-in Tennessee increased approximately 10-fold. NAS surveillance is relatively new, and underestimation associated with surveillance has not been described. We compared data from the Tennessee NAS public health surveillance system (TNSS) with a second source of NAS data, hospital discharge data system (HDDS), and estimated the true number of infants with NAS using capture-recapture methods. METHODS: We obtained NAS data on cases of NAS among Tennessee infants from TNSS and HDDS from January 1, 2013, through December 31, 2016. We matched cases of NAS identified in TNSS to cases identified in HDDS. We estimated the true number of infants with NAS by using the Lincoln-Peterson estimator capture-recapture methodology. RESULTS: During the study period, 4070 infants with NAS were reported to TNSS, and 5321 infants with NAS were identified in HDDS; 2757 were in both data sets. Using capture-recapture methods, the total estimated number of infants with NAS during the study period was 7855 (annual mean = 1972; estimated range = 1531-2427), which was 93% more than in TNSS and 48% more than in HDDS. Drugs used for the medication-assisted treatment of substance use disorder were the most commonly reported substances associated with NAS (n = 2389, 59%). CONCLUSIONS: TNSS underestimated the total burden of NAS based on the capture-recapture estimate. Case-based public health surveillance is important for monitoring the burden of and risk factors for NAS and helping guide public health interventions.


Subject(s)
Cost of Illness , Neonatal Abstinence Syndrome/epidemiology , Public Health Surveillance , Humans , Infant, Newborn , Substance-Related Disorders , Tennessee/epidemiology
13.
Am J Ind Med ; 62(6): 535-541, 2019 06.
Article in English | MEDLINE | ID: mdl-31046143

ABSTRACT

BACKGROUND: Do workers follow their self-interest by minimizing injury risk in their employment decision? If so, employers could use injury reduction as a recruitment and retention strategy. This study explores whether injury incidence is associated with turnover in Montana's Oil and Gas industry. METHODS: A panel data set of Unemployment Insurance and Workers' Compensation administrative records from 2010 to 2015 was used to model the relationship between turnover and injury claim rates at the firm level. RESULTS: Total turnover and injury rates were found to be positively related while injury rates and separation rates had no such association. Quarters in which the employer experienced a severe injury had a 3.3 percentage point increase in separation rates. DISCUSSION: The findings suggest that injured workers contribute to increased turnover, but coworker turnover does not increase with increased injury rates in the firm. Secondary findings suggest a relationship between recent hires and increased injury rates, although further investigation is required.


Subject(s)
Occupational Injuries/epidemiology , Oil and Gas Industry , Personnel Turnover/statistics & numerical data , Workers' Compensation/statistics & numerical data , Adult , Cohort Studies , Humans , Incidence , Montana , Retrospective Studies , Risk Assessment
15.
Ann Surg Oncol ; 26(5): 1320-1325, 2019 May.
Article in English | MEDLINE | ID: mdl-30805812

ABSTRACT

BACKGROUND: Technology to assess tissue perfusion is exciting with translational potential, although data supporting its clinical applications have been lagging. Patients who have undergone radiation are at particular risk of poor tissue perfusion and would benefit from this expanding technology. We designed a prospective clinical trial using intraoperative indocyanine green angiography to evaluate for wound-healing complications in patients undergoing salvage laryngectomy after radiation failure. PATIENTS AND METHODS: This prospective trial included patients undergoing salvage laryngectomy at a National Cancer Institute-designated tertiary cancer center between 2016 and 2018. After tumor extirpation and prior to reconstruction, 10 mg indocyanine green dye was infused and the fluorescence (FHYPO) and ingress rate of the pharyngeal mucosa recorded. The primary outcome measure was formation of a pharyngocutaneous fistula (PCF). RESULTS: Patients who developed a PCF had significantly lower FHYPO (87 vs 172, p < 0.001) and ingress rates (6.7 vs 15.8, p = 0.043) compared with those who did not develop a fistula. There were no fistulas in patients with FHYPO > 150 (n = 21) or ingress > 15 (n = 15). There was a 50% fistula rate in patients with FHYPO ≤ 103 (n = 10) and ingress rate ≤ 6 (n = 6). CONCLUSIONS: Intraoperative indocyanine green angiography can assess hypoperfusion in patients and predict risk of PCFs after salvage laryngectomy, and can thus intraoperatively risk-stratify patients for postoperative wound-healing complications.


Subject(s)
Cutaneous Fistula/diagnosis , Fluorescein Angiography/methods , Laryngeal Neoplasms/surgery , Laryngectomy/adverse effects , Monitoring, Intraoperative , Pharyngeal Diseases/diagnosis , Salvage Therapy , Aged , Coloring Agents/administration & dosage , Cutaneous Fistula/diagnostic imaging , Cutaneous Fistula/etiology , Female , Follow-Up Studies , Humans , Indocyanine Green/administration & dosage , Laryngeal Neoplasms/pathology , Male , Middle Aged , Pharyngeal Diseases/diagnostic imaging , Pharyngeal Diseases/etiology , Postoperative Complications , Prognosis , Prospective Studies
16.
Surg Endosc ; 33(8): 2521-2530, 2019 08.
Article in English | MEDLINE | ID: mdl-30350107

ABSTRACT

BACKGROUND: Bariatric surgery is the most effective treatment for morbid obesity; however, there may be significant unanticipated psychosocial effects following surgery. Prior studies have identified a threefold increase in the incidence of alcohol use disorder (AUD) after Roux-en-Y gastric bypass (RYGB). With sleeve gastrectomy (SG) now comprising over 50% of primary bariatric operations, the degree to which patients who undergo SG develop AUD remains unknown. We sought to characterize the patients and incidence of AUD following SG compared to RYGB. METHODS: This study used prospectively collected data from a state-wide quality collaborative. The presence of AUD was determined using the Alcohol Use Disorders Identification Test for Consumption (AUDIT-C), with a score ≥ 4 in men and ≥ 3 in women suggestive of AUD. We used bivariate Chi-square tests for categorical variables and independent samples t tests for continuous variables. We used multivariable logistic regression to identify patient characteristics that may predispose patients to development of AUD at 1 and 2 years after surgery. RESULTS: The overall prevalence of AUD in our population (n = 5724) was 9.6% preoperatively, 8.5% at 1 year postoperatively, and 14.0% at 2 years postoperatively. The preoperative, 1-year, and 2-year prevalence of AUD for SG were 10.1%, 9.0%, and 14.4%, respectively. The preoperative, 1-year, and 2-year postoperative prevalence of AUD for RYGB were 7.6%, 6.3%, and 11.9%, respectively. Predisposing patient factors to AUD development included higher educational level (p < 0.01) and higher household income (p < 0.01). CONCLUSIONS: This is first large, multi-institutional study of AUD following SG. The prevalence of alcohol use disorder in patients undergoing SG and RYGB was similar pre- and postoperatively. The majority of patients developed AUD following their second postoperative year. Understanding the timing and incidence of alcohol use disorder in patients undergoing SG-the most commonly performed bariatric operation in the United States-is critical to providing appropriate counseling and treatment.


Subject(s)
Alcoholism/epidemiology , Gastrectomy/adverse effects , Gastric Bypass/adverse effects , Postoperative Complications/epidemiology , Adult , Alcoholism/etiology , Female , Humans , Logistic Models , Male , Middle Aged , Obesity, Morbid/surgery , Postoperative Complications/etiology , Prevalence , Prospective Studies
17.
Laryngoscope ; 129(8): 1836-1843, 2019 08.
Article in English | MEDLINE | ID: mdl-30570748

ABSTRACT

Head and neck squamous cell carcinomas are aggressive tumors that often present at advanced stage in difficult-to-biopsy regions of the head and neck. With the rapid move to analyze circulating tumor DNA (ctDNA) to either detect cancer or monitor disease progression and response to therapy, we have designed this article as a primer to understand the recent studies that support a transition to use these circulating biomarkers as a part of routine clinical care. Whereas some technical challenges still need to be overcome, the utility of ctDNA in cancer care is already evident from these early studies. Therefore, it is critical to understand recent advances in this area as well as emerging questions that need to be addressed as these biomarkers move closer to enhancing routine clinical care paradigms. Laryngoscope, 129:1836-1843, 2019.


Subject(s)
Biomarkers, Tumor/analysis , Circulating Tumor DNA/analysis , Sentinel Surveillance , Squamous Cell Carcinoma of Head and Neck/diagnosis , Adult , Disease Progression , Female , Humans , Male , Middle Aged , Saliva/chemistry , Sensitivity and Specificity , Squamous Cell Carcinoma of Head and Neck/metabolism
20.
Int J Pediatr Otorhinolaryngol ; 114: 170-174, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30262359

ABSTRACT

OBJECTIVE: This study aims to determine the effect of auricular scaffold microarchitecture on chondrogenic potential in an in vivo animal model. METHODS: DICOM computed tomography (CT) images of a human auricle were segmented to create an external anatomic envelope. Image-based design was used to generate 1) orthogonally interconnected spherical pores and 2) randomly interspersed pores, and each were repeated in three dimensions to fill the external auricular envelope. These auricular scaffolds were then 3D printed by laser sintering poly-l-caprolactone, seeded with primary porcine auricular chondrocytes in a hyaluronic acid/collagen hydrogel and cultured in a pro-chondrogenic medium. The auricular scaffolds were then implanted subcutaneously in rats and explanted after 4 weeks for analysis with Safranin O and Hematoxylin and Eosin staining. RESULTS: Auricular constructs with two micropore architectures were rapidly manufactured with high fidelity anatomic appearance. Subcutaneous implantation of the scaffolds resulted in excellent external appearance of both anterior and posterior auricular surfaces. Analysis on explantation showed that the defined, spherical micropore architecture yielded histologic evidence of more robust chondrogenic tissue formation as demonstrated by Safranin O and Hematoxylin and Eosin staining. CONCLUSIONS: Image-based computer-aided design and 3D printing offers an exciting new avenue for the tissue-engineered auricle. In early pilot work, creation of spherical micropores within the scaffold architecture appears to impart greater chondrogenicity of the bioscaffold. This advantage could be related to differences in permeability allowing greater cell migration and nutrient flow, differences in surface area allowing different cell aggregation, or a combination of both factors. The ability to design an anatomically correct scaffold that maintains its structural integrity while also promoting auricular cartilage growth represents an important step towards clinical applicability of this new technology.


Subject(s)
Ear Auricle/surgery , Plastic Surgery Procedures/methods , Tissue Engineering/methods , Tissue Scaffolds/chemistry , Animals , Cells, Cultured , Chondrocytes/cytology , Computer-Aided Design , Ear Cartilage/cytology , Humans , Printing, Three-Dimensional , Prostheses and Implants , Rats , Swine , Tomography, X-Ray Computed
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