Plasma Epstein-Barr virus immunoglobulin A and DNA for nasopharyngeal carcinoma screening in the United States.

OBJECTIVE: To examine the Epstein-Barr virus (EBV) IgA and DNA assays as a screening tool for nasopharyngeal carcinoma (NPC) in a nonendemic US population. STUDY DESIGN AND SETTING: Prospective study performed at a teaching hospital in New York City. There were two groups of 155 patients: new NPC patients and controls. An otolaryngologic examination and serial blood testing for serologic markers were performed. RESULTS: Sensitivity and specificity of EBV IgA and DNA assays were determined. Screening scenarios involving series and parallel testing were evaluated to determine economic feasibility. Series testing provided a sensitivity, specificity, and positive and negative predictive values of 90.6, 93.5, 78.4, and 97.5 percent, respectively. Parallel testing increased the sensitivity to 100 percent. CONCLUSION: NPC screening in a high-risk, nonendemic population using EBV-specific serologic markers is effective. Series testing is a statistically sound and economically feasible strategy. SIGNIFICANCE: The development of a cost-effective NPC screening strategy in a high-risk, nonendemic population in the United States.

Combined anterior-to-posterior and posterior-to-anterior approach to paranasal sinus surgery: an update.

OBJECTIVES: To develop an anatomically and functionally based approach to endoscopic intranasal ethmoidectomy; to develop such an approach using the salient features of the anterior-to-posterior (AP) and posterior-to-anterior (PA) intranasal sinus operations; to assess the safety of this form of ethmoidectomy in a patient population. STUDY DESIGN: Retrospective chart review of patients undergoing ethmoidectomy by the authors or by residents under their direct supervision. SETTING: University teaching hospital. RESULTS: Two thousand three hundred and forty-four patients underwent either unilateral or bilateral ethmoidectomies between April 1992 and August 2005. A complication rate of 0.34% was observed. CONCLUSIONS: Combining an AP approach to conserve sinus anatomy with a PA approach to avoid surgery directed toward the skull base provides a functional and safe procedure, as demonstrated by the reported results.

Multiple motor unit recordings of laryngeal muscles: the technique of vector laryngeal electromyography.

OBJECTIVES: To display time-series firing rate and recruitment data for multiple, simultaneously active motoneurons activating human laryngeal muscles. These data provide specific information about how laryngeal muscle force is being controlled by the central nervous system at the level of the lower motoneuron. METHODS: A quadrifilar needle electrode was used to record multi-channel myoelectric signals from thyroarytenoid muscle of normal subjects during tasks ranging from quiet breathing to a short sentence. Motor unit action potentials of the signal space were identified and tracked throughout task productions using pattern recognition and Precision Decomposition software. RESULTS: We present the first recordings and analyses of multiple motor unit activations in the larynx. The firing times and mean firing rates are plotted for each identified motor unit, which reveal recruitment and decruitment information and the database from which common firing statistics across motor units may be derived. CONCLUSIONS: This study provides new information about neuromuscular physiology of the larynx. Specifically, the results reveal the ordered recruitment and firing patterns of multiple motor units and the existence of common drive from the central nervous system. The technique may prove fundamental to understanding various neuromuscular pathologies such as laryngeal spasm and to assist clinical prognosis of laryngeal paresis and the diagnosis of certain neurogenic disorders.