Citations

Abstract QUESTION 1 What is the expected diagnostic yield for vestibular schwannomas when using a magnetic resonance imaging (MRI) to evaluate patients with previously published definitions of asymmetric sensorineural hearing loss? TARGET POPULATION These recommendations apply to adults with an asymmetric sensorineural hearing loss on audiometric testing. RECOMMENDATION Level 3: On the basis of an audiogram, it is recommended that MRI screening on patients with ≥10 decibels (dB) of interaural difference at 2 or more contiguous frequencies or ≥15 dB at 1 frequency be pursued to minimize the incidence of undiagnosed vestibular schwannomas. However, selectively screening patients with ≥15 dB of interaural difference at 3000 Hz alone may minimize the incidence of MRIs performed that do not diagnose a vestibular schwannoma. QUESTION 2 What is the expected diagnostic yield for vestibular schwannomas when using an MRI to evaluate patients with asymmetric tinnitus, as defined as either purely unilateral tinnitus or bilateral tinnitus with subjective asymmetry? TARGET POPULATION These recommendations apply to adults with subjective complaints of asymmetric tinnitus. RECOMMENDATION Level 3: It is recommended that MRI be used to evaluate patients with asymmetric tinnitus. However, this practice is low yielding in terms of vestibular schwannoma diagnosis (<1%). QUESTION 3 What is the expected diagnostic yield for vestibular schwannomas when using an MRI to evaluate patients with a sudden sensorineural hearing loss? TARGET POPULATION These recommendations apply to adults with a verified sudden sensorineural hearing loss on an audiogram. RECOMMENDATION Level 3: It is recommended that MRI be used to evaluate patients with a sudden sensorineural hearing loss. However, this practice is low yielding in terms of vestibular schwannoma diagnosis (<3%). The full guideline can be found at: https://www.cns.org/guidelines/guidelines-management-patients-vestibular-schwannoma/chapter_2.

Objective: The goal of the present study was to assess the sound quality of a cochlear implant for single-sided deaf (SSD) patients fit with a cochlear implant (CI). Background: One of the fundamental, unanswered questions in CI research is “what does an implant sound like?” Conventional CI patients must use the memory of a clean signal, often decades old, to judge the sound quality of their CIs. In contrast, SSD-CI patients can rate the similarity of a clean signal presented to the CI ear and candidate, CI-like signals presented to the ear with normal hearing. Methods: For Experiment 1 four types of stimuli were created for presentation to the normal hearing ear: noise vocoded signals, sine vocoded signals, frequency shifted, sine vocoded signals and band-pass filtered, natural speech signals. Listeners rated the similarity of these signals to unmodified signals sent to the CI on a scale of 0 to 10 with 10 being a complete match to the CI signal. For Experiment 2 multitrack signal mixing was used to create natural speech signals that varied along multiple dimensions. Results: In Experiment 1 for eight adult SSD-CI listeners, the best median similarity rating to the sound of the CI for noise vocoded signals was 1.9; for sine vocoded signals 2.9; for frequency upshifted signals, 1.9; and for band pass filtered signals, 5.5. In Experiment 2 for three young listeners, combinations of band pass filtering and spectral smearing lead to ratings of 10. Conclusion: The sound quality of noise and sine vocoders does not generally correspond to the sound quality of cochlear implants fit to SSD patients. Our preliminary conclusion is that natural speech signals that have been muffled to one degree or another by band pass filtering and/or spectral smearing provide a close, but incomplete, match to CI sound quality for some patients.

BackgroundImproving the quality of healthcare is a complex and resource intensive process. To optimize the allocation of scarce resources, quality improvement (QI) should focus on high‐value diseases that will produce the largest improvement in health system performance. Given the breadth and multidisciplinary nature of sinonasal disease management, the purpose of this study was to transparently develop a prioritized list of sinonasal diseases for QI from the perspective of the specialty of rhinology and the American Rhinologic Society (ARS).MethodsThe RAND modified Delphi methodology was used to rank the priority of nine sinonasal disease categories from 1 (lowest priority) to 9 (highest priority). Two rounds of ranking along with a teleconference meeting was performed by a panel of 9 experts from the ARS Quality Improvement Committee.ResultsThe final QI‐prioritized list of sinonasal diseases are as follows: chronic rhinosinusitis (CRS) (mean score = 8.9), recurrent acute rhinosinusitis (RARS) (mean score = 7.9), sinonasal neoplasms (mean score = 7.0), anatomic nasal obstruction (mean score = 5.9), refractory epistaxis (mean score = 5.2), complicated acute rhinosinusitis (mean score = 5.2), chronic nonallergic rhinitis (mean score = 4.4), orbital disease (mean score = 4.3), uncomplicated acute rhinosinusitis (mean score = 4.1), and allergy/allergic rhinitis (mean score = 3.7).ConclusionThe three most important disease categories for QI from the perspective of the specialty of rhinology were CRS, RARS, and sinonasal neoplasms. Future studies need to define and validate quality metrics for each of these important disease categories in order to facilitate appropriate measurement and improvement initiatives.

Background: The first description of the voluntary motor function of the facial nerve and separate sensory-motor contributions of the trigeminal nerve is most commonly attributed to Charles Bell. However, a review of the original scientific accounts and subsequent historical publications question the validity of this credit. The objective of the present historical analysis is to clarify the contributions of Herbert Mayo toward discovering the functions of the fifth and seventh cranial nerves and to raise awareness of this historical controversy within the medical literature. Methods: Review of Charles Bell's and Herbert Mayo's original dissertations published between 1821 and 1823, and subsequent reports relevant to these primary works. Results: Bell's submissions to the Royal Society of London in 1821 and 1822 describe the seventh nerve as the “respiratory nerve of the face” responsible for involuntary coordination of facial movement with the organs of respiration. Separately, Bell states that the fifth nerve is responsible for sensibility and voluntary movement of the facial muscles. In these accounts, Bell only peripherally alludes to the motor function of the seventh nerve and often comments inaccurately on fifth and seventh cranial nerve innervation. In contrast, in 1822 and 1823, Herbert Mayo first accurately and unequivocally defined the voluntary motor function of the facial nerve and sensory-motor function of the trigeminal nerve on the basis of his detailed experiments. The ultimate transfer of acknowledgment to Bell was rooted in surreptitious reworking of Bell's original dissertations and personal attacks against Mayo rather than arguments of scientific merit. Conclusion: Several notable clinicians and anatomists have contributed to our current understanding of the anatomy and physiology of the facial and trigeminal nerves, including Charles Bell; however, Herbert Mayo should be remembered for first providing a more accurate and clear description of their separate functions.

Abstract Dr Albert L. Rhoton Jr became the focal point of neurosurgery's evolution in understanding the intricate and complex microanatomy of the human brain over the last 4 decades. His pioneering work on cadaveric specimens proved to be a pivotal endeavor in the pursuit to better understand the complex microsurgical anatomy of cranial surgery. This paper details his early career at the Mayo Clinic in Rochester, Minnesota. A comprehensive review and synthesis of data acquired from the institutional historical archives including the Annual Reports to the Executive Committee, the Reports to the Board of Directors, the MAYOVOX Newsletter, the illustration archives of the Mayo Clinic Division of Creative Media, staff biographies, curriculum vitae, personal interviews, as well as full-text journal articles, and book publications was performed. Dr Rhoton was engaged in a busy clinical practice as a young staff at the Mayo Clinic. Records show he focused on tackling complex intracranial pathologies along with numerous basic research and neuroanatomy projects that became a major part of his life's work and passion. He was a great teacher and friend to countless individuals and his work will continue to impact and improve the care provided to neurosurgery patients for generations to come.

BackgroundMeasuring quality outcomes is an important prerequisite to improve quality of care. Rhinosinusitis represents a high value target to improve quality of care because it has a high prevalence of disease, large economic burden, and large practice variation. In this study we review the current state of quality measurement for management of both acute (ARS) and chronic rhinosinusitis (CRS).MethodsThe major national quality metric repositories and clearinghouses were queried. Additional searches included the American Academy of Otolaryngology–Head and Neck Surgery database, PubMed, and Google to attempt to capture any additional quality metrics.ResultsSeven quality metrics for ARS and 4 quality metrics for CRS were identified. ARS metrics focused on appropriateness of diagnosis (n = 1), antibiotic prescribing (n = 4), and radiologic imaging (n = 2). CRS quality metrics focused on appropriateness of diagnosis (n = 1), radiologic imaging (n = 1), and measurement of patient quality of life (n = 2). The Physician Quality Reporting System (PQRS) currently tracks 3 ARS quality metrics and 1 CRS quality metric. There are no outcome‐based rhinosinusitis quality metrics and no metrics that assess domains of safety, patient‐centeredness, and timeliness of care.ConclusionsThe current status of quality measurement for rhinosinusitis has focused primarily on the quality domain of efficiency and process measures for ARS. More work is needed to develop, validate, and track outcome‐based quality metrics along with CRS‐specific metrics. Although there has been excellent work done to improve quality measurement for rhinosinusitis, there remain major gaps and challenges that need to be considered during the development of future metrics.

Objectives: To compare the diagnostic yield of high-resolution volumetric T2-weighted MRI (HRT2-MRI) with high-resolution computed tomography (HRCT) for diagnosis of large vestibular aqueduct (LVA). Study Design: Three board-certified neuroradiologists performed an independent, blinded radiological review for diagnosing LVA with 2:1 age-matched controls on patients with both HRCT and HRT2-MRI imaging. Setting: Tertiary referral center. Patients: All patients between 2002 and 2016 with hearing loss who underwent both HRCT and HRT2-MRI and were diagnosed with LVA on either modality. Main Outcome Measures: Concordance rate for LVA between HRCT and HRT2-MRI. Results: Concordance rate for HRCT and HRT2-MRI for diagnosing LVA was 88% (124/141) when assessing both the midpoint and external aperture diameters. Fifteen ears had LVA on computed tomography (CT), but not on magnetic resonance imaging (MRI); in comparison, two ears had LVA on MRI, but not on CT (p = 0.002). Excellent inter-rater reliability among the three radiologists was demonstrated. Conclusion: Historically, HRCT has been the imaging modality of choice for diagnosing LVA. Although a higher concordance rate of HRT2-MRI was found compared with previous studies utilizing earlier MRI technology, HRCT still detected a larger number of patients with clinically significant hearing loss compared with MRI. Given the high concordance rate and efficacy of both modalities in diagnosing LVA, the ultimate decision of which modality to choose may depend on other patient-specific and clinical factors.

Hypothesis: A new generation 192-slice multi-detector computed tomography (MDCT) clinical scanner provides enhanced image quality and superior electrode localization over conventional MDCT. Background: Currently, accurate and reliable cochlear implant electrode localization using conventional MDCT scanners remains elusive. Methods: Eight fresh-frozen cadaveric temporal bones were implanted with full-length cochlear implant electrodes. Specimens were subsequently scanned with conventional 64-slice and new generation 192-slice MDCT scanners utilizing ultra-high resolution modes. Additionally, all specimens were scanned with micro-CT to provide a reference criterion for electrode position. Images were reconstructed according to routine temporal bone clinical protocols. Three neuroradiologists, blinded to scanner type, reviewed images independently to assess resolution of individual electrodes, scalar localization, and severity of image artifact. Results: Serving as the reference standard, micro-CT identified scalar crossover in one specimen; imaging of all remaining cochleae demonstrated complete scala tympani insertions. The 192-slice MDCT scanner exhibited improved resolution of individual electrodes (p < 0.01), superior scalar localization (p < 0.01), and reduced blooming artifact (p < 0.05), compared with conventional 64-slice MDCT. There was no significant difference between platforms when comparing streak or ring artifact. Conclusion: The new generation 192-slice MDCT scanner offers several notable advantages for cochlear implant imaging compared with conventional MDCT. This technology provides important feedback regarding electrode position and course, which may help in future optimization of surgical technique and electrode design.

Abstract BACKGROUND One study has investigated postoperative growth rates following subtotal resection of petroclival meningiomas utilizing linear measurements, which are insensitive to the multidimensional complex growth of meningiomas, to estimate tumor volume. OBJECTIVE To describe petroclival meningioma growth patterns following less-than-complete resection utilizing volumetric analysis and to identify variables associated with tumor progression. METHODS Patients with surgically resected WHO grade I petroclival meningiomas were retrospectively reviewed (1999-2015). Image analysis software was utilized to perform volumetric analyses of tumor size and growth on serial MRI studies. The impact of preoperative and postoperative variables on tumor growth after subtotal resection was analyzed. An increase in tumor volume of at least 20% was defined as “tumor growth.” RESULTS Twenty-three patients had immediate preoperative and serial postoperative MRI studies available for review. The mean preoperative tumor volume was 20.9 cm 3 (range 0.4-54.6). The mean extent of resection was 75.5% (range 31.5%-100.0%). At a mean follow-up of 24.8 mo, 12 tumors (66.7%) exhibited radiological tumor growth, while 6 tumors did not change in size. The median annual volumetric growth rate was 2.82 cm 3 /yr (range –0.34 to 10.1). Extent of resection and immediate postoperative tumor volume were significantly correlated with the annual volumetric growth rate following resection. At last follow-up, 3 (13%) patients required further intervention. CONCLUSION The majority of petroclival meningiomas exhibit growth following subtotal resection. Extent of resection is strongly associated with risk for disease progression following surgery.