Content Validity of a High-Fidelity Surgical Middle Ear Simulator: A Randomized Prospective International Multicenter Trial.

OBJECTIVE: After demonstration of face validity of a surgical middle ear simulator (SMS) previously, we assessed the content validity of the simulator with otolaryngology residents. STUDY DESIGN: Multicenter randomized prospective international study. SETTING: Four academic institutions. METHODS: Novice participants were randomized into control, low-fidelity (LF), and high-fidelity (HF) groups. Control and LF produced 2 recordings from 2 attempts, and HF produced 4 recordings from 10 attempts, with trials 1, 4, 7, and 10 used for scoring. Three blinded experts graded videos of the simulated stapedectomy operation using an objective skills assessment test format consisting of global and stapedotomy-specific scales. RESULTS: A total of 152 recordings from 61 participants were included. Baseline characteristics did not differ significantly between groups. Depending on the step of the operation, inter-rater reliability ranged from 24 to 90%. For LF and HF, years of training was significantly associated with improved scores in certain objective skills assessment test subparts. HF outperformed the control group on stapes and global scores ( p < 0.05). The HF group demonstrated improvement in global score over trials, but plateaued after four trials. Scores varied greatly for participants from different institutions in certain operative steps, such as transecting incudostapedial joints, likely due to differences in instrumentation and time elapsed since manufacture. CONCLUSION: Practice with SMS led to better performance in both global and stapes-specific scores. Further studies are needed to examine construct validity and to create otology-appropriate grading systems. Variables like instrumentation and decline in flexibility of the simulator after 12 months greatly affect performance on the simulator.

Impact of Cochlear Dose on Hearing Preservation Following Stereotactic Radiosurgery in Treatment of Vestibular Schwannomas: A Multi-Center Study.

OBJECTIVE: Stereotactic radiosurgery (SRS) is a well-established treatment for vestibular schwannomas (VS). Hearing loss remains a main morbidity of VS and its treatments, including SRS. The effects of radiation parameters of SRS on hearing remain unknown. The goal of this study is to determine the effect of tumor volume, patient demographics, pretreatment hearing status, cochlear radiation dose, total tumor radiation dose, fractionation, and other radiotherapy parameters on hearing deterioration. METHODS: Multicenter retrospective analysis of 611 patients who underwent SRS for VS from 1990-2020 and had pre- and post-treatment audiograms. RESULTS: Pure tone averages (PTAs) increased and word recognition scores (WRSs) decreased in treated ears at 12-60 months while remaining stable in untreated ears. Higher baseline PTA, higher tumor radiation dose, higher maximum cochlear dose, and usage of single fraction resulted in higher post radiation PTA; WRS was only predicted by baseline WRS and age. Higher baseline PTA, single fraction treatment, higher tumor radiation dose, and higher maximum cochlear dose resulted in a faster deterioration in PTA. Below a maximum cochlear dose of 3 Gy, there were no statistically significant changes in PTA or WRS. CONCLUSIONS: Decline of hearing at one year in VS patients after SRS is directly related to maximum cochlear dose, single versus 3-fraction treatment, total tumor radiation dose, and baseline hearing level. The maximum safe cochlear dose for hearingtbrowd preservation at one year is 3 Gy, and the use of 3 fractions instead of one fraction was better at preserving hearing.

Sensorineural Hearing Loss and Tinnitus Characteristics in Patients With Idiopathic Intracranial Hypertension.

OBJECTIVES: To characterize patterns of sensorineural hearing loss (SNHL) and tinnitus in patients with idiopathic intracranial hypertension (IIH). STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS: Adult patients diagnosed with IIH via lumbar puncture (LP) between 2010 and 2020 who had available audiograms. The study included a total of 40 patients; 33 women, and 7 men with a median age of 43. INTERVENTIONS: Diagnostic LP and audiogram. MAIN OUTCOME MEASURES: Otologic symptoms, ophthalmologic signs, hearing thresholds, cerebrospinal fluid opening pressures. RESULTS: The most commonly reported symptoms were tinnitus in 28 (70%, 23 pulsatile and 5 tonal), aural fullness in 11 (28%), and vertigo in 10 (25%). Twenty-nine patients had ophthalmologic examinations and 18 had evidence of papilledema. Twenty-five (63%) patients had hearing loss in at least one ear at one frequency range. Patients presented with both unilateral and bilateral hearing loss across low, middle, and high frequency ranges. No significant association was observed between hearing loss threshold and LP opening pressure except for 250 Hz in the left ear. After stratification by tinnitus group (pulsatile, tonal, and no tinnitus), no significant difference was found between mean hearing loss threshold at different frequencies. In addition, no significant mean age difference was identified in patients within each tinnitus group. CONCLUSIONS: There was no classic pattern or presentation for hearing loss in our IIH patients. They developed sudden, unilateral, or bilateral SNHL in low, middle, or high frequency range. The degree of hearing loss did not correlate with CSF opening pressure.

Antibiotic resistance among Escherichia coli and Salmonella isolated from dairy cattle feces in Texas.

In several developing countries, studies on antimicrobial resistance among bacteria from food animals are rare mostly because of under-resourced laboratories. The objective of this study was to develop and field-test a low cost protocol to estimate the isolate- and sample-level prevalence of resistance to critically important antibiotics among Escherichia coli and Salmonella isolated from dairy cattle feces. Using a predesigned protocol, fecal samples were collected to isolate non-type-specific E. coli and Salmonella using selective media without antibiotic supplements. Besides, samples were screened for E. coli and Salmonella isolates not susceptible to third-generation cephalosporins and quinolones using selective media supplemented with cefotaxime (1.0 µg/mL) and ciprofloxacine (0.5 µg/mL), respectively. All bacterial isolates were further tested for antibiotic susceptibility using disk diffusion. Bacterial isolates not susceptible to third-generation cephalosporins were tested for extended spectrum beta-lactamase (ESBL) phenotype using the combination disk test. Molecular methods were performed on selected bacterial isolates to identify and distinguish genetic determinants associated with the observed phenotypes. Among 85 non-type-specific E. coli isolated from MacConkey agar without antibiotics, the isolate-level prevalence of resistance to tetracycline was the highest (8.2%). Among 37 E. coli recovered from MacConkey agar with cefotaxime, 56.8% were resistant ceftriaxone. Among 22 E. coli isolates recovered from MacConkey agar with ciprofloxacin, 77.3% and 54.5% were resistant to nalidixic acid and ciprofloxacin, respectively. Sixteen Salmonella were isolated and only one demonstrated any resistance (i.e., single resistance to streptomycin). Among E. coli isolates not susceptible to ceftriaxone, an AmpC phenotype was more common than an ESBL phenotype (29 versus 10 isolates, respectively). Whole genome sequencing showed that phenotypic profiles of antibiotic resistance detected were generally substantiated by genotypic profiles. The tested protocol is suited to detecting and estimating prevalence of antimicrobial resistance in bacteria isolated from food animal feces in resource-limited laboratories in the developing world.

Sensorineural Hearing Loss Caused by Labyrinthine Erosion Due to a Cerebrospinal Fluid Diverticulum.

OBJECTIVE: To present a case of progressive sensorineural hearing loss (SNHL) caused by labyrinthine erosion secondary to expanding geniculate ganglion cerebrospinal fluid (CSF) diverticulum extending along the path of the facial nerve. PATIENT: Thirteen-year-old man with no past medical history or risk factors presented with unilateral progressive SNHL and no other otologic or neurologic symptoms. INTERVENTIONS: Audiological data as well as imaging studies including a magnetic resonance imaging (MRI) of the brain and internal auditory canal and a temporal bone computed tomography (CT) are presented. Partial labyrinthectomy, CSF leak closure, and cochlear implantation were performed. A lumbar puncture was obtained 2 months postoperatively. MAIN OUTCOME MEASURE: Closure of the CSF leak. RESULTS: Mastoidectomy revealed a wide area of CSF leak through the geniculate ganglion and fallopian canal with partial destruction of the superior and lateral semicircular canals by an expanding diverticulum. CONCLUSIONS: This is an unusual presentation of progressive SNHL due to partial labyrinthine erosion due to a meningocele of the geniculate ganglion along the fallopian canal. It is likely that the patient had a congenital open pathway through the labyrinthine segment of the facial nerve and CSF pulsations created the meningocele over a few years. This case argues for early closure of such CSF diverticula to prevent possible SNHL due to labyrinthine erosion.

Antibiotic-Resistant Escherichia coli and Salmonella from the Feces of Food Animals in the East Province of Rwanda.

In Rwanda, information on antibiotic resistance in food animals is scarce. This study was conducted to detect and phenotypically characterize antibiotic-resistant Escherichia coli and Salmonella in feces of cattle, goats, pigs, and poultry in the East province of Rwanda. We isolated non-type-specific (NTS) E. coli and Salmonella using plain culture media. In addition, we used MacConkey agar media supplemented with cefotaxime at 1.0 µg/mL and ciprofloxacin at 0.5 µg/mL to increase the probability of detecting E. coli with low susceptibility to third-generation cephalosporins and quinolones, respectively. Antibiotic susceptibility testing was performed using the disk diffusion test. Among 540 NTS E. coli isolates, resistance to tetracycline was the most frequently observed (35.6%), followed by resistance to ampicillin (19.6%) and streptomycin (16.5%). Percentages of NTS E. coli resistant to all three antibiotics and percentages of multidrug-resistant strains were higher in isolates from poultry. All isolated Salmonella were susceptible to all antibiotics. The sample-level prevalence for resistance to third-generation cephalosporins was estimated at 35.6% with all third-generation cephalosporin-resistant E. coli, expressing an extended-spectrum beta-lactamase phenotype. The sample-level prevalence for quinolone resistance was estimated at 48.3%. These results provided a baseline for future research and the development of integrated surveillance initiatives.

Frecuencia de anticuerpos anti-Vhc y tatuaje corporal en miembros del personal de la Armada: Comando fluvial de Ciudad Bolívar. Noviembre 2003 - Junio 2004

Introducción: desde el descubrimiento del VHC y hasta el presente, existe un gran porcentaje de casos sin una vía obvia de transmisión, lo cual ha conllevado a investigar otra forma de contagio, menos estudiada. Se ha planteado que la acción de realizarse tatuajes corporales puede representar un medio de transmisión de la enfermedad digno de ser evaluado seriamente debido a la naturaleza de la técnica, con la consiguiente posibilidad de transmitir al virus con el instrumental utilizado. En el presente trabajo se realizó un estudio para determinar la frecuencia de anticuerpos Anti-VHC y tatuaje corporal. Pacientes: 130 pacientes, miembros del personal de la Armada, destacados en el Comando Fluvial de Ciudad Bolívar (noviembre de 2003 hasta junio de 2004). Metodología: la investigación se realizó mediante una encuesta y la toma muestras de sangre para la detección de anticuerpos anti-VHC, utilizando la técnica de inmunoensayo enzimático indirecta UMELISA HCV. Los resultados fueron tabulados y se realizó el análisis estadístico descriptivo de los mismos. Resultados: ningún miembro del personal de la Armada resultó reactivo para anticuerpo anti-VHC, encontrándose el 26,92% de ellos con tatuaje corporal. De los individuos tatuados, 77,14% presentaron sólo un tatuaje corporal, y 88,57% de éstos utilizó aguja estéril para la realización del mismo. Conclusión: no se encontró asociación entre tatuaje corporal y la presencia de anticuerpos anti-VHC, por lo que no se logró evidenciar esta posible vía de transmisión de la infección. Se puede considerar que la seronegatividad al anticuerpo anti-VHC puede deberse a que, en su mayoría, los individuos presentaron un sólo tatuaje corporal y los mismos fueron realizados con aguja estéril, reduciendo así el riesgo al contagio de la infección.

Introduction: Since the discovery of HCV until now, there have been a significant percentage of cases without a clear way of transmission, making necessary to investigate other means of contamination, not so well studied, such as corporal tattooing. This could represent a way of transmission worth to evaluate, due to the nature of its technique and the instruments used in its elaboration. In this study, we determined the frequency of Anti-VHC antibodies and corporal tattoo. Patients: 130 patients, all navy personal members, assigned to the Fluvial Commando in Ciudad Bolívar (from November 2003 to June 2004). Methodology: the research was performed using polls and blood samples, for the detection of anti-HCV antibodies, using the UMELISA HCV method. The results were tabulated with their respective statistical analysis. Results: no one in the navy personal resulted reactive for anti-VHC antibodies, 26, 92% of them had corporal tattoo. Within this group, 77, 14% had only one corporal tattoo, and 88, 57% used sterile needle for drawing the tattoo. Conclusion: no association was found between corporal tattoo and anti-HCV antibodies, demonstrating this possible way of transmission to be unlikely. It has to be considered that being seronegative to anti-VHC antibodies could be explained because the great majority of individuals had only one corporal tattoo, and they were made with sterile needles, reducing their risk.