Peter G. Michaelson

Validations of a portable home sleep study with twelve-lead polysomnography: comparisons and insights into a variable gold standard.

Objectives: Accurate and timely diagnosis for patients with obstructive sleep apnea (OSA) is imperative. Unfortunately, growing interest in this diagnosis has resulted in increased requests and waiting times for polysomnography (PSG), as well as a potential delay in diagnosis and treatment. This study evaluated the accuracy and viability of utilizing SNAP (SNAP Laboratories, LLC, Wheeling, Illinois), a portable home sleep test, as an alternative to traditional PSG in diagnosing OSA. Methods: This prospective clinical trial included 59 patients evaluated at our institutions sleep laboratory. Concurrent PSG and SNAP testing was performed for 1 night on each patient. Independent, blinded readers at our institution and at an outside-accredited institution read the PSG data, and 2 independent, blinded readers interpreted the SNAP data at SNAP laboratories. The apnea-hypopnea index (AHI) was used to compare the 2 testing modalities. The correlation coefficient, receiver operating characteristic curve analysis, and the Bland-Altman curves, as well as sensitivity, specificity, inter-reader variability, positive predictive value, and negative predictive value, were used to compare SNAP and PSG. Results: There is a definitive, statistically sound correlation between the AHIs determined from both PSG and SNAP. This relationship holds true for all measures of comparison, while displaying a concerning, weaker correlation between the different PSG interpretations. Conclusions: There is a convincing correlation between the study-determined AHIs of both PSG and SNAP. This finding supports SNAP as a suitable alternative to PSG in identifying OSA, while accentuating the inherent variation present in a PSG-derived AHI. This test expands the diagnostic and therapeutic prowess of the practicing otolaryngologist by offering an alternative OSA testing modality that is associated with not only less expense, decreased waiting time, and increased convenience, but also statistically proven accuracy.

Popular snore aids: do they work?

OBJECTIVE: The study goal was to critically evaluate 3 popular noninvasive treatments for snoring: an oral spray lubricant applied before bedtime, a nasal strip designed to maintain nasal valve patency, and a head-positioning pillow. STUDY DESIGN: Prospective, randomized blinded clinical trial of 3 popular noninvasive snore aids using objective acoustic snoring analysis and subjective patient and bed-partner questionnaires in 40 snoring patients. A digital recorder allowed snoring analysis with data collected in the home environment over 1 week. RESULTS: There is neither objective nor subjective benefit to the use of tested popular noninvasive snore aids. Palatal snoring, palatal loudness, average loudness of snoring, averaged palatal flutter frequency, and respiratory disturbance index did not significantly change when comparing the 3 snoring aids with no treatment. Subjective comments and complications are reviewed as well. CONCLUSION: This is the first prospective comparison trial of popular noninvasive snoring aids. There is no significant objective or subjective snoring improvement in the anti-snoring aids studied compared with the use of no aid. SIGNIFICANCE: Outcome studies aid in verifying or refuting claims made by popular noninvasive snore aids. (Otolaryngol Head Neck Surg 2004;130: 649-58.)

Metastatic Renal Cell Carcinoma Presenting in the External Auditory Canal

A57-year-old male previously in good health presented to his primary care physician with sudden onset of left-sided subjective hearing loss and aural fullness. Examination revealed a small polypoid, friable mass in the left external auditory canal. Excisional biopsy findings were consistent with metastatic renal cell carcinoma, and the patient subsequently was referred to our institution, where further diagnostic workup, including renal biopsy, confirmed the diagnosis. Physical examination at that time revealed regrowth of the aural mass, which now completely occluded the external auditory canal and protruded from the meatus (Fig 1). Audiogram revealed a mixed profound hearing loss in the left ear, and MRI of the internal auditory canals and brain demonstrated multiple intracranial metastasis with erosion of middle-ear structures.

Tracheal paraganglioma presenting with acute airway obstruction.

p a m w c s S aragangliomas of the larynx are rare lesions that are ften confused with other primary and secondary layngeal neoplasms. Location in the subglottis is excepionally rare. These lesions are often misinterpreted as edullary thyroid carcinoma (MTC). Accurate microcopic and immunohistochemical analysis combined ith clinical and radiographic examinations are critical or proper diagnosis. In this report, we describe a case f a recurrent tracheal paraganglioma presenting with cute airway obstruction and hemorrhage following riginal misdiagnosis and treatment as MTC.

Seldinger-assisted videotelescopic intubation (SAVI): a common sense approach to the difficult pediatric airway.

OBJECTIVES: To describe the Seldinger-assisted videotelescopic intubation (SAVI) technique, a complementary method for aiding in difficult pedi-atric intubations that uses common equipment available to the practicing otolaryngologist. STUDY DESIGN: Technique description. METHODS: Detailed description of technique for use of a pediatric laryngoscope with video-assisted endotracheal tube (ETT) covered rigid tracheoscopy controlled intubation in difficult pediatric airways. RESULTS: In our practice, SAVI is vital in establishing a secure airway in the difficult-to-intubate child. After insertion of a laryngoscope, an appropriate sized endotracheal tube is delivered through the glottis under direct video-visualization from a rigid telescope using a variation of the well-established Seldinger technique. The telescope serves as the stable ETT stylet that also provides panoramic visualization. The ETT slides over the telescope to provide a secure airway directly visible to all in the operating room. Benefits of the SAVI technique to previously described video-assisted intubations with flexible or specially designed endoscope devices include decreased cost, employment of previously existing endoscopy skills, the benefit of rigid delivery of the endotracheal tube as well as innate versatility to a multitude of clinical situations. CONCLUSIONS: The SAVI technique offers an additional practical clinical solution to the difficult pediatric airway. Although ultimately establishing the airway depends on the skills of the operator, the SAVI technique has saved multiple lives by using common equipment through a common-sense approach. EBM rating: D. (Otolaryngol Head Neck Surg 2005;132:677-680.)

Mesenchymal chondrosarcoma of sinonasal cavity: a case report and brief literature review

Abstract Mesenchymal chondrosarcoma is a rare, highly malignant cartilaginous forming tumor that is rarely encountered in clinical practice. They are unique in their ability to frequently arise in the soft tissues in addition to the common skeletal sites of other bone tumors. Histologically, mesenchymal chondrosarcomas are characterized by a mix of cartilage and undifferentiated stromal tissue. Radiographically, they demonstrate features similar to the more commonly encountered conventional chondrosarcoma, with the tumor location and patient age helping to suggest the correct diagnosis. We present a case of mesenchymal chondrosarcoma presenting as chronic sinusitis, arising in the sinonasal cavity. Additionally, a discussion of the imaging features and a brief review of the literature surrounding this uncommon neoplasm are included.

Home Versus Laboratory Sleep Studies

Mark Ghegan et al.1 recently published a timely paper, “Laboratory versus Portable Sleep Studies: A MetaAnalysis.” We commend the authors on an in-depth review of a complex topic. Efforts to distill and reconcile bodies of work are essential to growth and understanding. Meta-analysis is a collection of systematic statistical techniques designed to resolve apparent contradictory research findings. Criticisms of meta-analysis commonly fall into two types. First, meta-analysis may distort clinical importance by “averaging” simple numbers across studies. Second, the results of a meta-analysis must be very carefully considered before making conclusions. The following comments follow these two critiques and are directed to the two issues the authors raised against home testing. Ghegan et al. concluded in their meta-analysis, “Home sleep studies provide similar diagnostic information to laboratory polysomnograms (PSGs) in the evaluation of sleepdisordered breathing but may underestimate sleep apnea severity.” They based this conclusion on a statement that “the respiratory disturbance index (RDI) in portable sleep studies [as calculated by the reviewers] to be 10% lower on average than that observed with in-laboratory polysomnography.” The authors ultimately acknowledged that such a small difference might not be important, stating, “Further study is warranted to determine whether the [10%] decreased sensitivity is of clinical relevance.” For the 10% averaged reduced sensitivity of the home testing to be of any clinical relevance, two criteria must be simultaneously established. First, a clinician reviewing the patient’s data might make a different and wrong clinical decision because of a 10% reduction in RDI. Second is that multi-night in-laboratory PSGs on the same patient exhibit less than 10% average RDI difference. In fact, neither is true. First, let us accept as given that the observed difference of 10% is real across these two settings. It is our contention that we can objectively dismiss the relevance of this difference from the data at hand. For example, reduce the analysis to a continuum of RDIs ranging from 0 to 100. Clearly, a 10% difference in RDI would not impact the treatment decision in any outcome throughout this range. At one extreme, the patient would have an RDI of 5 versus 5.5. At the other extreme, the results would be an RDI of 90 versus 99. Neither example shown here, nor any other on this range, reflect a clinical difference that would change a physician’s treatment decision or impact their patient care plan. Second, a substantial body of published peer-reviewed research indicates that PSG night-to-night variability of more than 10% is common for the same patient tested under the same conditions. These data support a conclusion that the observed 10% difference is not truly home versus inlaboratory PSG; rather, it can be more easily explained as a reflection of human variance in apnea or error inherent to the PSG. For example, in a study comparing night-to-night variability in in-laboratory PSG, Mosko et al.,2 in testing 46 elderly patients on 3 nights, reported that the average RDI on night 2 was 18.9% lower than the RDI of night 3. Similarly, the night 1 RDI was 11.3% lower than that recorded on night 3. In another study, Lord et al.3 reported average RDIs over 4 nights in a laboratory PSG study to vary as much as 25%. Note, in Lord et al., night 3 RDI was the lowest, whereas in Mosko et al. night 3 is the highest. This argues that the issue is not merely an ordinal or “first night effect.” Rather, it is likely that either 1) random statistical variability is inherent in apnea, as measured by in-laboratory PSG or 2) there is noise that is within the error of the measuring method. Either position supports a conclusion that a 10% difference between two monitoring events is clinically immaterial. In the famous words of statesman Henry Clay, “Statistics are no substitute for judgment.” It is important to note that the only other expressed reservation to portable home sleep testing was an anecdotal suspicion that a slightly higher rate of retesting in unmonitored conditions might reduce the admitted home test cost advantage. Again, we do not have to leave this to speculation. There are numerous examples in the market of home testing services that allow for multiple night recording at one flat cost and will retest at no charge whenever a recording was unsuccessful. Therefore, the market shows us that the somewhat higher rate of repeat testing under home conditions should not have any effect on the admitted savings of home testing. The authors report that the “current gold standard for diagnosing [obstructive sleep apnea] is an overnight, inlaboratory PSG.” Some physicians now realize that this gold standard is tarnished. Unfortunately, many do not. There is no question that the equipment used for routine PSG is accurate and repeatable; however, when the digital information filters through a study reader, there lies the potential for interpretation and bias. This affects the determination of most recorded and determined variables (including RDI) and is confounded by variables such as first night effect and reading (hypopnea) criteria. It needs to be accepted that home sleep studies will never completely agree with PSGs because of these variables. Home sleep studies should be considered an alternative as long as it accurately classifies those patients with and without obstructive sleep apnea. In conclusion, the meta-analysis by Ghegan et al. raised only two issues against home testing for obstructive sleep apnea. On close inspection, both appear to be without sufficient merit. Given the widely acknowledged benefits of home testing (greater patient access to a diagnosis, lower costs of diagnosis, and more timely treatment initiation) as well as the widely recognized adverse impact of untreated apnea on patient health outcomes (higher health care use, worsening of comorbid conditions, and higher mortality rates), the data reviewed should be seen as a strong endorsement of the value to increase our judicial use of home testing.

Popular noninvasive snoring aids: do they work?

other baseline measures ranged 0.004-0.24 (mean, 0.09), with one association significant of 40 tested (arousal index and SF-36 Mental Component Summary, r 0.24, P 0.03). Correlations between change in PSG indices and change in other outcome measures ranged 0.0001-0.39 (mean, 0.15), with two significant associations of 40 tested (apnea index and FOSQ, r 0.30, P 0.03; lowest saturation and SNORE25, r 0.39, P 0.005). Apnea-hypopnea index was not associated in any case. Conclusions: PSG indices are not consistently associated with sleepiness, QOL, or reaction time, both at baseline and as outcome measures. PSG indices may not quantify some important aspects of sleep apnea disease burden or treatment outcome. Clinically important outcomes should be measured directly.

West Nile virus: A primer for the otolaryngologist

BACKGROUND Since recognition in the United States with a 1999 New York City epidemic, West Nile virus has enduringly migrated westward, leaving few states unaffected. Infection rates are rising at an alarming rate, doubling every year since introduction, with more than 9800 cases in 2003 alone and more than 260 deaths. Patients may present with myriad symptoms including a maculopapular rash that affects the face and trunk and diffuse lymphadenopathy, both of which may result in the initial consultation of the otolaryngologist. We review the clinical history of West Nile virus and its epidemiology, laboratory findings, and variable clinical presentation, with an emphasis on otolaryngologic manifestations. STUDY DESIGN AND SETTING COMPREHENSIVE: review of the literature over the past 50 years with an emphasis on what the present-day otolaryngologist needs to know concerning West Nile virus. Clinical manifestations of the head and neck such as encephalitis, meningitis, maculopapular rash, lymphadenopathy and dysphagia are discussed. RESULTS To date, there are no articles in the otolaryngology literature discussing West Nile virus. These patients may present initially to multiple providers in diverse specialties because of multifarious initial signs and symptoms. The otolaryngologist must be educated on this quickly growing affliction and practice with a high index of suspicion. CONCLUSIONS In this article we describe the clinical manifestations of West Nile virus, with an emphasis on the otolaryngologic manifestations. The otolaryngologist must become educated about this entity to facilitate preventative measures, adequately treat, and assist other providers in hopeful control and potential eradication of this infectious threat.

The portable home sleep study: A suitable alternative to polysomnography?

Abstract Objectives: Accurate and timely diagnosis and treatment for patients with obstructive sleep apnea (OSA) is imperative. Growing interest in this threatening disorder has resulted in increased requests and waiting times for polysomnography (PSG), as well as a potential delay in diagnosis and treatment. This study evaluated PSG with a portable home sleep test (SNAP) to investigate the validity of this alternative testing modality. Methods: This prospective clinical trial included over 60 patients evaluated at our institution’s sleep laboratory. Concurrent PSG and SNAP testing was performed for 1 night on each patient. The PSG data were read by independent blinded readers at our institution as well as multiple outside accredited institutions. The SNAP data were read at their laboratory by multiple independent blinded readers. The respiratory index most correlative with PSG confirmed OSA; the apnea-hypopnea index (AHI), was used to compare the 2 testing modalities. Results: There is a definitive, statistically sound correlation between the determined AHI from both PSG and SNAP. AHI’s from multiple independent readings of both testing modalities revealed a strong Pearson’s correlation that was significant at the 0.01 level (2-tailed) ranging from 0.7 to 0.97 for all comparison tests. Conclusions: There is a convincing correlation between the study determined AHI of both PSG and SNAP. This finding, the first of its kind in the otolaryngology literature, expands the diagnostic and therapeutic prowess of the practicing otolaryngologist by offering an alternative OSA testing modality that is associated with not only less expense, decreased waiting time, and increased convenience, but statistically proven accuracy.