Hypoglossal schwannoma masquerading as a carotid body tumor.

Study Objective. To describe the clinical presentation, evaluation, and treatment of a hypoglossal schwannoma. Methods. We report an unusual case of a hypoglossal schwannoma presenting as a pulsatile level II neck mass at the bifurcation of the external and internal carotid arteries, mimicking a carotid body tumor. Radiologic findings are reviewed in detail. Results. A 59-year-old female presented to a tertiary care medical center with complaints of a pulsatile right-sided neck mass. An MRA of the neck was obtained demonstrating a 5 cm mass located at the carotid artery bifurcation and causing splaying of the internal and external carotids. Based on clinical presentation and imaging, a diagnosis of a carotid body tumor was conferred and the patient scheduled for excision. Intraoperatively, the mass was noted to arise from the hypoglossal nerve, remaining independent of the carotid artery. On histopathologic analysis, the mass was determined to be consistent with hypoglossal schwannoma. Conclusion. Though rare, the hypoglossal schwannoma should remain a consideration in the evaluation of a parapharyngeal space mass. As this report demonstrates, the clinical and radiologic presentation of a hypoglossal schwannoma may closely mimic that of the more common carotid body tumor

Spectroscopic Study of 75^{75}As and 139^{139}La NMR on Layered Structure Ferromagnet LaCoAsO

$^{75}$As and $^{139}$La field-swept NMR spectra were obtained for the novel weakly itinerant ferromagnet LaCoAsO with 2D layered structure above the Curie temperature of 55 K. By analyzing NMR spectra, temperature dependences of Knight shift $K$ and nuclear quadrupole resonance frequency $\nu_Q$ were obtained successfully for each nucleus. We confirmed from the so-called $K$-$\chi$ plots that the macroscopic magnetization of our {LaCoAsO} powder sample is intrinsic and does not contain the contribution from impurity phases. We estimated hyperfine coupling constants from the slope of $K$-$\chi$ plots and compared to that of iron-arsenide superconductor.Comment: 5 pages, 5 figures, published on J. Phys. Soc. Jpn. at Vol.79, pp.054703 (2010)

Hypoglossal Schwannoma Masquerading as a Carotid Body Tumor

Study Objective. To describe the clinical presentation, evaluation, and treatment of a hypoglossal schwannoma. Methods. We report an unusual case of a hypoglossal schwannoma presenting as a pulsatile level II neck mass at the bifurcation of the external and internal carotid arteries, mimicking a carotid body tumor. Radiologic findings are reviewed in detail. Results. A 59-year-old female presented to a tertiary care medical center with complaints of a pulsatile right-sided neck mass. An MRA of the neck was obtained demonstrating a 5 cm mass located at the carotid artery bifurcation and causing splaying of the internal and external carotids. Based on clinical presentation and imaging, a diagnosis of a carotid body tumor was conferred and the patient scheduled for excision. Intraoperatively, the mass was noted to arise from the hypoglossal nerve, remaining independent of the carotid artery. On histopathologic analysis, the mass was determined to be consistent with hypoglossal schwannoma. Conclusion. Though rare, the hypoglossal schwannoma should remain a consideration in the evaluation of a parapharyngeal space mass. As this report demonstrates, the clinical and radiologic presentation of a hypoglossal schwannoma may closely mimic that of the more common carotid body tumor

Vocal Fold Cancer Transoral Laser Microsurgery Following European Laryngological Society Laser Cordectomy Classification

BackgroundThe surgical treatment of glottic, or vocal cord, cancer has seen considerable progression over the past several decades. Specifically, there has been a stark transition from open partial laryngectomy surgery to endoscopic laser microsurgical techniques which have been inspired in large part by two landmark studies: Professor Wolfgang Steiner’s original case series describing transoral laser microsurgery for glottic cancer (1993) and the European Laryngological Society’s (ELS) classification scheme (2000). We performed a comprehensive review of published literature to characterize the pattern of this novel modality as compared with two landmark studies over the past four decades.MethodsAn English literature search was conducted on PubMed for available original investigations on surgical treatment of glottic laryngeal cancer published over the past 40 years. Our Boolean criteria included the following terms: cancer, glottic, laryngeal, surgery, endoscopic, and laser. The publication rates were calculated as annual compound growth as well as corrected growth rates as defined by the Fisher equation for inflation effects.ResultsOur review identified 13,372 studies covering larynx cancer and 3,557 studies covering glottic cancer original studies. Among these, we analyzed the compound annual growth rates and correct growth rates for three distinct publication periods or epochs, prior to 1993, 1993–1999, and 2000–2017. For all but two of the search term groups covering both glottic cancer as well as larynx cancer, there was a substantial growth improvement in the time period following the ELS classification scheme as compared with the growth rate of the time period following Steiner’s case series.ConclusionThe progress toward minimally invasive treatment of glottic cancer has progressed steadily over the past several decades. Analysis of publication show increased growth during the time period following the ELS classification scheme over the time period following Steiner’s landmark study. A mistake would be concluding any diminished importance of Professor Steiner’s work, instead, our analysis demonstrates the wide-spread adoption of the endoscopic laser cordectomy procedure following the ELS classification system. Complex surgical techniques such as transoral laser microsurgery are optimally disseminated within well-defined classification schemes, though further validation is warranted

Investigation of modified speciation for enhanced control of mercury

Mercury was identified as a hazardous air pollutant in Title 3 of the 1990 Clean Air Act Amendments. It has been singled out for particular scrutiny because of its behavior in the environment (bioaccumulation) and its potential for deleterious effects on humans and wildlife. After studying the sources of mercury in the environment, the US Environmental Protection Agency has concluded that coal-fired boilers generate a significant fraction of the total anthropogenic emissions. Therefore, the agency is currently considering whether to impose mercury control requirements on coal-fired boilers in the electric utility industry. However, the costs for potential control measures (such as sorbent injection) can be extremely high. Mercury removal with chloric acid solutions was tested. The presence of NO increased Hg removal. It appeared that both gas-gas and gas-liquids reactions were operating, with the gas-phase reactions involving NO becoming increasingly important as the solute concentration was raised. From these studies, it was concluded that even higher Hg{sup 0} removals could be obtained if more of the reagent was made available for reaction in the gas phase. For this reason (and also to simulate a more real-world duct-injection process) a new series of tests was initiated in which an ultrasonic atomizer was used to inject small droplets of the oxidizing solutions into a flowing gas stream containing Hg{sup 0} vapors and other typical flue-gas components. The results of those tests are described in this paper