Sudden sensorineural hearing loss and delayed complete sudden spontaneous recovery.

This is a case report of a 53-yr-old female who experienced sudden sensorineural hearing loss (SSNHL) accompanied by roaring tinnitus in her right ear. The patient's hearing partially improved in the low frequencies in response to intratympanic injections. Given that her hearing loss did not improve further, the patient was fitted with a hearing aid to mask the tinnitus and restore a sense of balance between the two ears. Approximately 9 mo postonset of the SSNHL, a complete spontaneous recovery of hearing occurred. Such a delayed and complete recovery is highly unusual. This case highlights that the spontaneous recovery in hearing indicates that the pathological cause for the SSNHL involved a process that was capable of repair or regeneration, thus ruling out pathologies related to cochlear hair cell destruction or nerve fiber loss. This leaves a possibility that the event causing the onset of the SSNHL resulted in a disruption of the ion homeostatic properties of the cochlea via the production of the endocochlear potential.

Auditory brainstem response testing in neurodiagnosis: structure versus function.

This case report describes a 44-yr-old female referred by an outside facility who presented with progressive hearing loss in her left ear. Magnetic resonance imaging (MRI) results were normal, but a battery of audiological tests suggested neural hearing loss in the left ear. Following diagnosis of left neural hearing loss, the patient was successfully fit with a hearing aid on the left ear. This case report underlines the importance of using a battery of medical, radiologic, and audiological tests in the accurate determination of hearing loss site of lesion. Obvious retrocochlear dysfunction was revealed via auditory brainstem response (ABR) testing. MRI did not reveal underlying structural abnormality. Without the addition of the ABR to the diagnostic test battery, a cochlear hearing loss site of lesion would most likely have been diagnosed. Accurate diagnosis of hearing loss site of lesion is critical for patient counseling and treatment as well as for patient follow-up and monitoring.

Practical guide to efficient analysis and diagramming articles.

OBJECTIVE: In a busy practice, time is a commodity in rare supply, and keeping abreast of the relevant medical literature is a daunting task. Even after reading an article carefully, important information may be lost because of undue attention to the methodological minutia. METHOD: Fundamental to reducing a complex article into a well-organized and consistent format is the technique of quantitatively diagramming the principal components in the design and findings of the study. This approach allows a coherent brief summary statement of the article, and a platform for a focused scientific discussion and analysis of the clinical applicability of the findings. CONCLUSIONS: The technique of diagramming an article is a tool that the senior author has used for years and has found it valuable in capturing the scientific fundamentals of a manuscript. Once prepared, the diagram has proven to be useful in clarifying presentations during journal club, preparing the background and significance sections of grant applications, reviewing articles as a journal editor and as a journal reviewer, and easily retrieving documents to support evidence-based practice efforts.

A practical guide for understanding confidence intervals and P values.

The 95 percent confidence interval about the mean demarcates the range of values in which the mean would fall if many samples from the universal parent population were taken. In other words, if the same observation, experiment, or trial were done over and over with a different sample of subjects, but with the same characteristics as the original sample, 95 percent of the means from those repeated measures would fall within this range. This gives a measure of how confident we are in the original mean. It tells us not only whether the results are statistically significant because the CI falls totally on one side or the other of the no difference marker (0 if continuous variables; 1 if proportions), but also the actual values so that we might determine if the data seem clinically important. In contrast, the P value tells us only whether the results are statistically significant, without translating that information into values relative to the variable that was measured. Consequently, the CI is a better choice to describe the results of observations, experiments, or trials.

Practical guide to understanding the value of case reports.

Case reports have been vital to the advancement of medicine, providing a mechanism for scholarly education and for sharing new discovery and rare observations. However, journals are increasingly reluctant to publish this type of manuscript. Additionally, case reports and limited case series are infrequently cited, potentially interfering with the impact factor of a journal. The increasing emphasis on evidence-based medicine may have artificially decreased the value of case reports. This article describes the value of case reports to medicine, citing 3 examples that have significantly improved the practice of medicine. We also provide criteria for effective reporting, which include the elements of both surprise and closure. In summary, we offer support for the contention that case reports are fundamental to the scholarly practice of medicine and enhance the intent of a quality medical journal.

Nucleus Freedom North American clinical trial.

OBJECTIVE: To evaluate hearing outcomes and effects of stimulation rate on performance with the Nucleus Freedom cochlear implant (Cochlear Americas, Denver, CO). STUDY DESIGN AND SETTING: Randomized, controlled, prospective, single-blind clinical study using single-subject repeated measures (A-B-A-B) design at 14 academic centers in the United States and Canada and comparison with outcomes of a prior device by the same manufacturer. PATIENTS: Seventy-one severely/profoundly hearing impaired adults. RESULTS: Seventy-one adult recipients were randomly programmed in two different sets of rate: ACE or higher rate ACE RE. Mean scores for Consonant Nucleus Consonant words is 57%, Hearing in Noise Test (HINT) sentences in quiet 78%, and HINT sentences in noise 64%. Sixty-seven percent of subjects preferred slower rates of stimulation, and performance did not improve with higher rates of stimulation using this device. CONCLUSIONS: Subjects performed well, and there was no advantage to higher stimulation rates with this device. SIGNIFICANCE: Higher stimulation rates do not necessarily result in improved performance.

In vivo estimates of the position of advanced bionics electrode arrays in the human cochlea.

OBJECTIVES: A new technique for determining the position of each electrode in the cochlea is described and applied to spiral computed tomography data from 15 patients implanted with Advanced Bionics HiFocus I, Ij, or Helix arrays. METHODS: ANALYZE imaging software was used to register 3-dimensional image volumes from patients' preoperative and postoperative scans and from a single body donor whose unimplanted ears were scanned clinically, with micro computed tomography and with orthogonal-plane fluorescence optical sectioning (OPFOS) microscopy. By use of this registration, we compared the atlas of OPFOS images of soft tissue within the body donor's cochlea with the bone and fluid/ tissue boundary available in patient scan data to choose the midmodiolar axis position and judge the electrode position in the scala tympani or scala vestibuli, including the distance to the medial and lateral scalar walls. The angular rotation 0 degrees start point is a line joining the midmodiolar axis and the middle of the cochlear canal entry from the vestibule. RESULTS: The group mean array insertion depth was 477 degrees (range, 286 degrees to 655 degrees). The word scores were negatively correlated (r = -0.59; p = .028) with the number of electrodes in the scala vestibuli. CONCLUSIONS: Although the individual variability in all measures was large, repeated patterns of suboptimal electrode placement were observed across subjects, underscoring the applicability of this technique.

The P Value Problem in Otolaryngology: Shifting to Effect Sizes and Confidence Intervals.

There is a lack of reporting effect sizes and confidence intervals in the current biomedical literature. The objective of this article is to present a discussion of the recent paradigm shift encouraging the use of reporting effect sizes and confidence intervals. Although P values help to inform us about whether an effect exists due to chance, effect sizes inform us about the magnitude of the effect (clinical significance), and confidence intervals inform us about the range of plausible estimates for the general population mean (precision). Reporting effect sizes and confidence intervals is a necessary addition to the biomedical literature, and these concepts are reviewed in this article.

CT-derived estimation of cochlear morphology and electrode array position in relation to word recognition in Nucleus-22 recipients.

This study extended the findings of Ketten et al. [Ann. Otol. Rhinol. Laryngol. Suppl. 175:1-16 (1998)] by estimating the three-dimensional (3D) cochlear lengths, electrode array intracochlear insertion depths, and characteristic frequency ranges for 13 more Nucleus-22 implant recipients based on in vivo computed tomography (CT) scans. Array insertion depths were correlated with NU-6 word scores (obtained one year after SPEAK strategy use) by these patients and the 13 who used the SPEAK strategy from the Ketten et al. study. For these 26 patients, the range of cochlear lengths was 29.1-37.4 mm. Array insertion depth range was 11.9-25.9 mm, and array insertion depth estimated from the surgeon's report was 1.14 mm longer than CT-based estimates. Given the assumption that the human hearing range is fixed (20-20,000 Hz) regardless of cochlear length, characteristic frequencies at the most apical electrode (estimated with Greenwood's equation [Greenwood DD (1990) A cochlear frequency--position function of several species--29 years later. J Acoust. Soc. Am. 33: 1344-1356] and a patient-specific constant as) ranged from 308 to 3674 Hz. Patients' NU-6 word scores were significantly correlated with insertion depth as a percentage of total cochlear length (R = 0.452; r2 = 0.204; p = 0.020), suggesting that part of the variability in word recognition across implant recipients can be accounted for by the position of the electrode array in the cochlea. However, NU-6 scores ranged from 4% to 81% correct for patients with array insertion depths between 47% and 68% of total cochlear length. Lower scores appeared related to low spiral ganglion cell survival (e.g., lues), aberrant current paths that produced facial nerve stimulation by apical electrodes (i.e., otosclerosis), central auditory processing difficulty, below-average verbal abilities, and early Alzheimer's disease. Higher scores appeared related to patients' high-average to above-average verbal abilities. Because most patients' scores increased with SPEAK use, it is hypothesized that they accommodated to the shift in frequency of incoming sound to a higher pitch percept with the implant than would normally be perceived acoustically.

Measurement of facial muscle strength in normal subjects.

OBJECTIVES: Muscle strength is a fundamental measure of function for neuromuscular systems; however, mimetic facial muscle strength has never been recorded. The objective of the present feasibility project was to measure facial muscle strength. STUDY DESIGN: The study design was a prospective experimental trial in 10 normal subjects. Descriptive statistics, tests, and analysis of variance were used to summarize and compare data. METHODS: Subjects were selected by convenience following submission and approval of a prospectively designed protocol and consent form to the Human Studies Committee. Application of a force transducer to the central eyebrow and commissure during eyebrow raising, eyelid closing, smiling, and puckering was performed by two methods: surface adhesion method (n = 5) and direct probe application method (n = 5). Data were recorded in pounds. Three repetitions of each movement were made. RESULTS: Rank order of muscle strengths (in pounds) by the surface adhesion technique was as follows: brow, 0.758; eye, 0.549; pucker, 0.387; and smile, 0.307. By direct probe application the rank order of muscle strengths was as follows: eye, 0.880; brow, 0.773; and smile, 0.730. CONCLUSIONS: Objective measures of facial motion are crucial for quantitative investigations of preventative, therapeutic, reconstructive, and rehabilitative interventions for facial nerve and muscle lesions. Until the present, objective measures required cross-correlations with current standards that were subjective. This is the first time an actual physical measure of facial muscle function has been performed. The purpose of presenting this preliminary work is to stimulate advancement along this line of research.

Tutorials in clinical research, part VIII: Creating a journal club.

OBJECTIVE: The present report is the eighth in a series of sequential tutorials entitled "Tutorials in Clinical Research." The objective of the report is to provide the reader with information to create or refine a journal club. STUDY DESIGN: Tutorial. METHODS: The authors met weekly for 3 months and discussed the features of a journal club that would be of interest to otolaryngologists. A Medline search provided a number of relevant articles for review. RESULTS: The report is organized into the following sections: Introduction, History of Journal Club, Goals of Journal Club, Basic Organization, Factors Associated With Successful Journal Clubs, Design of Journal Club, Selecting Literature, Evaluation of Journal Club, and Summary. CONCLUSIONS: There is a paucity of information within the otolaryngology literature regarding the journal club and the significant role it can play in physician education. The flexible nature of the journal club gives it the potential to address many educational needs. Its relevance has never been greater.

Tutorials in clinical research: part V: outcomes research.

OBJECTIVES: This is the fifth in a series of sequential "Tutorials in Clinical Research." The objective of the present report is to give the reader a broad overview of the field of outcomes research. This summary is intended to enable the reader to understand outcomes research methodology and to start the design of an outcomes research study. STUDY DESIGN: Tutorial. METHODS: The authors developed the report from available materials and refined it to be concise but complete for use by the practicing clinician. RESULTS: We describe the basic steps of record-based and patient-based outcomes research, including development of a staging system, identification of comorbid conditions, and creation or identification of an outcomes instrument. CONCLUSION: Outcomes research is a unique methodology that uses patient-based outcomes to assess the effectiveness of medical treatment.

Tutorials in clinical research: part VII. Understanding comparative statistics (contrast)--part A: general concepts of statistical significance.

OBJECTIVES/HYPOTHESIS: The present tutorial is the seventh in a series of Tutorials in Clinical Research. The specific purpose of the tutorial (Part A) and its sequel (Part B) is to introduce and explain three commonly used statistical tools for assessing contrast in the comparison between two groups. STUDY DESIGN: Tutorial. METHODS: The authors met weekly for 10 months discussing clinical research studies and the applied statistics. The difficulty was not in the material but in the effort to make the report easy to read and as short as possible. RESULTS: The tutorial is organized into two parts. Part A, which is the present report, focuses on the fundamental concepts of the null hypothesis and comparative statistical significance. The sequel, Part B, discusses the application of three common statistical indexes of contrast, the chi2, Mann-Whitney U, and Student t tests. CONCLUSIONS: Assessing the validity of medical studies requires a working knowledge of research design and statistics; obtaining this knowledge need not be beyond the ability of the busy surgeon. The authors have tried to construct an accurate, easy-to-read, easy-to-apply, basic introduction to comparing two groups. The long-term goal of the present tutorial and others in the series is to facilitate basic understanding of clinical research, thereby stimulating reading of some of the numerous well-written research design and statistical texts. This knowledge may then be applied to the continuing educational review of the literature and the systematic prospective analysis of individual practices.

Tutorials in clinical research: VII. Understanding comparative statistics (contrast)--part B: application of T-test, Mann-Whitney U, and chi-square.

OBJECTIVE: This tutorial on comparative statistics has been written in two complementary segments. The first paper (part A) focused on explaining the general concepts of the null hypothesis and statistical significance. This second article (part B) addresses the application of three specific statistical tests. These two articles should be read sequentially and the first article should be available for reference while one reads the second. STUDY DESIGN: Tutorial. METHODS: The authors met weekly for 10 months to discuss clinical research articles and the applied statistics. The difficulty was not the material but the effort to make it easy to read and as short as possible. RESULTS: The article discusses the application of three common statistical indexes of contrast, chi2, Mann-Whitney U, and Student t-test and other concepts, such as sample size, degrees of freedom, errors, power, and confidence intervals. CONCLUSIONS: Statistical tests generate a number known as a statistic (chi2, U, t), which is sometimes called a "critical ratio" because it helps us to make a decision. This number is then associated with a probability, or P value. Sample size is a crucial element in the initial design of a research project and in the subsequent ability of the results to show statistical significance if the difference is clinically important. The example data used in this paper demonstrate the application of the three specific tests and illustrate the effect of sample size on the results.

Tutorials in clinical research, part VI: descriptive statistics.

OBJECTIVES: This is the sixth in a series of Tutorials in Clinical Research. The objectives of this tutorial are to produce a brief, step-by-step, user-friendly atlas with clinical scenarios and illustrative examples to serve as ready references and, it is hoped, to open an inviting door to understanding statistics. STUDY DESIGN: Tutorial. METHODS: The authors met weekly for 6 months discussing clinical research articles and the applied statistics. Liberal use of reference texts and discussion focused on constructing a tutorial that is factual as well as easy to read and understand. RESULTS: The tutorial is organized into five sections: Overview, Key to Descriptive Summaries, Steps in Summarizing Descriptive Data, Understanding the Summaries of Specific Data Types, and Understanding Scope or Dispersion of Data. CONCLUSIONS: Assessing the validity of medical studies requires a working knowledge of statistics; however, obtaining this knowledge need not be beyond the ability of the busy surgeon. Desire is the only limiting factor. We have tried to construct an accurate, basic, easy-to-read-and-apply introduction to the task of summarizing the characteristics of a single variable. This is known as descriptive statistics.

Tutorials in clinical research: part IV: recognizing and controlling bias.

OBJECTIVE: This is the fourth of a series of Tutorials in Clinical Research (1-3). The objectives of this article are to heighten reader awareness of biases and of methods to reduce their impact and to provide an easy reference document for the reader during future journal reading. STUDY DESIGN: Tutorial. METHODS: The authors met weekly for 4 months discussing clinical research articles and biases for which they might be at risk. Liberal use of reference texts and specific articles on bias were reviewed. Like the example by Sackett, biases were catalogued to create an easily understood reference. Articles were chosen to demonstrate how understanding bias might facilitate assessment of the validity of medical publications. RESULTS: The article is organized into three main sections. The first section introduces specific biases. Two tables serve as rapid reference tools. The second section describes the most common biases linked to specific research approaches and reviews techniques to minimize them. The last section demonstrates the application of the information to an article in a manner that can be applied to any article. CONCLUSIONS: Assessing the validity of a medical publication requires an awareness of bias for which the research is inherently at risk. A review of the publication to determine what steps the authors did or did not undertake to minimize the impact of biases on their results and conclusions helps establish the validity. This article should be of assistance in this critical review task.

Vestibular dysfunction after cochlear implantation.

OBJECTIVE: To determine the prevalence, symptom characteristics, and potential risk factors for vestibular symptoms after cochlear implantation. STUDY DESIGN: Case-control study design embedded within an ongoing cohort of patients undergoing implantation. SETTING: Academic medical center cochlear implant research program funded by the National Institutes of Health. PATIENTS: Seventy five eligible consecutive patients undergoing cochlear implantation. INTERVENTION: Medical record review. MAIN OUTCOME MEASURE: Recorded symptoms of vestibular symptoms after cochlear implantation. Subjects with vestibular symptoms were considered case subjects; those without vestibular symptoms were considered control subjects. RESULTS: Twenty-nine of 75 (39%) patients experienced dizziness postoperatively. Four patients experienced a single, transient acute vertigo attack occurring less than 24 hours after surgery. The majority, 25 patients, experienced delayed, episodic onset of vertigo. The median (interquartile range) time of delayed onset was 74 (26-377) days after implantation. Delayed dizziness manifested as spontaneous episodic or positional vertigo. Preoperative dizziness, age at implantation, and age at onset of hearing loss were significantly greater in the dizzy group. Preoperative electronystagmography did not differentiate between groups. CONCLUSIONS: Thirty-nine percent (29/75) of subjects with implants were dizzy after implantation. The majority of subjects experienced dizziness in a delayed episodic fashion. Dizziness was not related to implant activation. It seemed that delayed dizziness was not related to immediate surgical intervention but could result from chronic changes occurring in the inner ear; there was some suggestion this could take the form of endolymphatic hydrops.

Otologics Middle Ear Transducer Ossicular Stimulator: performance results with varying degrees of sensorineural hearing loss.

OBJECTIVES: This study was conducted to demonstrate the safety and efficacy of the Otologics Middle Ear Transducer (MET) Ossicular Stimulator and, in particular, to compare the audiologic benefits of this novel form of electromechanical stimulation with those of conventional acoustical amplification. MATERIAL AND METHODS: A total of 282 patients were implanted with the device in Europe and the USA. Pure-tone audiometry, speech recognition and subjective assessment of benefit were tested before the surgery and 2, 3, 6 and 12 months afterwards. The US patients were fitted with a digital hearing aid for a minimum of 4 weeks prior to surgery, and the same benefit measures were performed with the digital hearing aid and their "walk-in" hearing aid. RESULTS: Group mean postoperative bone and air conduction thresholds did not change significantly from preoperative levels. Postoperative air conduction thresholds decreased slightly in some individual patients, due to the mass loading effect exerted by the transducer on the ossicles. Sufficient gain was available to reach target prescription levels for moderate to severely impaired hearing individuals. Speech and subjective assessment of patient preference indicated that patients did as well or better with the MET Ossicular Stimulator than with their "walk-in" aid or the standardized digital aid. CONCLUSION: The capability of the MET Ossicular Stimulator to provide appropriate gain as a function of degree of hearing loss indicates that the device is a viable treatment for moderate to severe sensorineural hearing loss in adults.

Practical guide to understanding clinical research compliance.

Noncompliance with federal regulations, as monitored through institutional review boards for the ethical conduct of clinical research, can occur, even to seasoned investigators. The cause of this noncompliance can be that an investigator is overloaded, does not know the regulations, or does not take the time to pay attention to the details. Sometimes it happens just because of inevitable human error that can befall us all at any time. The authors begin by citing the inherent differences between clinical practice and clinical research. This is followed by an illustration of common noncompliance errors, with examples, followed by general and specific concepts and methods to minimize noncompliance events. The objective of this article is to condense the myriad details involved in conducting clinical research into a set of manageable recommendations that can be recalled easily before and during the research. The material supporting these recommendations comes from years of institutional review board work at several institutions and consultation with experienced principal investigators and their research coordinators.

Practical guide to understanding the need for clinical practice guidelines.

With recent changes in the landscape of health care, clinical practice guidelines (CPGs) have proliferated. Attitudes about guidelines differ considerably, forming 2 competing viewpoints with considerable tension between them. Some feel CPGs are unneeded or are efforts to create automated "cookie cutter" medical practice; at best, they are perceived as suggestions that may be altered by experience. Others feel they are mandates that must be followed to the letter. This article attempts to explain how and why we have arrived at this point and to explain the origins of the differing viewpoints. We begin by describing the 2 viewpoints and proceed to define the origin of medicine as a profession and to chronicle the evolution of health insurance, medical education, and scientific methods for evaluating evidence.