RESUMEN
Behavioral forward-masking thresholds with a spectrally notched-noise masker and a fixed low-level probe tone have been shown to provide accurate estimates of cochlear tuning. Estimates using simultaneous masking are similar but generally broader, presumably due to nonlinear cochlear suppression effects. So far, estimates with forward masking have been limited to frequencies of 1 kHz and above. This study used spectrally notched noise under forward and simultaneous masking to estimate frequency selectivity between 200 and 1000 Hz for young adult listeners with normal hearing. Estimates of filter tuning at 1000 Hz were in agreement with previous studies. Estimated tuning broadened below 1000 Hz, with the filter quality factor based on the equivalent rectangular bandwidth (QERB) decreasing more rapidly with decreasing frequency than predicted by previous equations, in line with earlier predictions based on otoacoustic-emission latencies. Estimates from simultaneous masking remained broader than those from forward masking by approximately the same ratio. The new data provide a way to compare human cochlear tuning estimates with auditory-nerve tuning curves from other species across most of the auditory frequency range.
Asunto(s)
Cóclea , Enmascaramiento Perceptual , Umbral Auditivo , Cóclea/fisiología , Nervio Coclear , Humanos , Ruido/efectos adversos , Enmascaramiento Perceptual/fisiología , Adulto JovenRESUMEN
Lumbar spinal stenosis (LSS) is one of the most common indications for surgery in the USA. The addition of instrumented fusion to decompression for the treatment of LSS has become common, but recent randomized controlled trials (RCTs) have produced percieved conflicting results with unclear clinical implications. This review seeks clarity through an analysis of available RCTs. We performed a search of the PubMed database for RCTs that directly addressed decompression vs. decompression and fusion for the surgical treatment of LSS. RCTs were screened and reviewed to compare content such as patient selection, pathology, radiographic criteria, and operative technique. Five RCTs resulted from our search and were included in our analysis. Two studies yielded class I data while three yielded class III data due to study design related issues. Heterogeneity between these studies is emphasized with regard to patient selection, LSS definition, spondylolisthesis, instability, and surgical technique. Efforts to decipher which patients will truly benefit from instrumented fusion for the surgical treatment of LSS are still ongoing. Surgeon judgment will remain a crucial component for surgical decision making until future trials provide clarity. Instrumented fusion should be tailored to the individual patient rather than incorporated as a routine practice.
Asunto(s)
Descompresión Quirúrgica/métodos , Vértebras Lumbares/cirugía , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Fusión Vertebral/métodos , Estenosis Espinal/cirugía , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Masculino , Estenosis Espinal/diagnóstico por imagen , Resultado del TratamientoRESUMEN
BACKGROUND: Resident applicants in neurosurgery often wonder what factors impact their chances of successfully matching. Using data published by the National Residency Match Program for 2009-2016, we examined which components of the Electronic Residency Application Service application correlated with successful residency matching. METHODS: Data were collected from the National Residency Match Program publication Charting Outcomes in the Match from all years it was available for neurosurgery (2009, 2011, 2014, 2016). Individual factors reported (number of contiguous ranks, research projects, publications and presentations, work experiences, volunteer experiences, United States Medical Licensing Examination Step 1 and 2 score deciles, categorical data about Alpha Omega Alpha status, Ph.D. degree, other degree, and strength of medical school National Institutes of Health funding) were aggregated for all 3 years. Categorical data were available only for U.S. seniors. Spearman correlation and χ2 were used for ranked data and categorical data, respectively. Separate analyses were run for U.S. seniors and independent applicants. RESULTS: For U.S. seniors applying to neurosurgery, number of contiguous ranks, United States Medical Licensing Examination Step 1 and 2 scores, research projects, Alpha Omega Alpha status, and medical school top 40 National Institutes of Health funding were significantly associated with successful matching of applicants. Number of volunteer experiences was nearly statistically significant. For independent applicants, only United States Medical Licensing Examination Step 1 and 2 scores and number of research projects were statistically significant. CONCLUSIONS: This is the first study to analyze National Residency Match Program data for predictors of success in neurosurgical matching. Students applying to neurosurgery residency and their mentors should be aware of which baseline objective factors are associated with match success.
Asunto(s)
Selección de Profesión , Competencia Clínica/normas , Internado y Residencia/métodos , Neurocirugia/educación , Neurocirugia/métodos , Humanos , Estados UnidosRESUMEN
Arteriovenous malformations of the brain can carry considerable morbidity and mortality in the setting of rupture. The complex angioarchitecture and hemodynamic alteration requires careful consideration in diagnostic and management approaches. In this review, the authors define the pathophysiology, outline diagnostic methods, and highlight current management approaches.
Asunto(s)
Diagnóstico por Imagen/métodos , Malformaciones Arteriovenosas Intracraneales/diagnóstico , Malformaciones Arteriovenosas Intracraneales/terapia , Manejo de la Enfermedad , HumanosRESUMEN
BACKGROUND: Rehospitalization rates are increasingly used as quality indicators for a variety of illnesses, including sickle cell disease. While one small, single center study suggested outpatient follow-up with a pediatric hematologist was associated with fewer rehospitalizations, no study has examined the effect of post-discharge outpatient follow-up on rehospitalization rates across ages and beyond a single site. PROCEDURE: This is a retrospective cohort study using Wisconsin Medicaid claims data for hospitalized children and adults with sickle cell disease from 2003 to 2007. The primary outcomes were rehospitalization at both 14 and 30 days after an index hospitalization for sickle cell pain crisis (ICD-9-CM codes 28242, 28262, 28264, 28269). Univariate survival analyses were performed based on outpatient visit, severe disease, asthma, and age. The Cox proportional hazards model was used for multivariate analyses yielding hazard ratios for the association between outpatient visits and subsequent rehospitalization rates. RESULTS: Of the 408 patients included, 42 (10.2%) patients were rehospitalized within 14 days and 70 (17.1%) were rehospitalized within 30 days. Multivariate analysis showed that an outpatient visit is associated with lower rates of both 30-day rehospitalization (Hazard Ratio (HR) 0.442; 95%CI: 0.330-0.593) and 14-day rehospitalization (HR 0.226; 95%CI: 0.124-0.412), with the majority of 30-day rehospitalizations occurring within 14 days. CONCLUSIONS: For sickle cell disease, post-discharge planning should emphasize early follow-up to prevent subsequent hospitalization and improve care quality. Pediatr Blood Cancer 2012; 58: 406-409. © 2011 Wiley Periodicals, Inc.