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Short-latency auditory responses were obtained by cross-correlation of continuous, pseudorandom noise stimuli with averaged scalp potentials from adults with normal hearing. Responses were recorded for spectrum levels of 14-74 dB for noise bandwidths from 800 to 6000 Hz. At the lowest intensity level of broadband noise, all 10 subjects showed replicable cross-correlation functions (CCFs), which were characterized by prominent positive peaks at delays (latencies) of 5-7 msec. Male subjects exhibited longer delays than females. Delay (latency) increased with decreasing stimulus intensity. Very early responses (less than 2 msec) attributable to cochlear microphonic, which were prominent in earlier work on guinea pigs, were not well seen in these human data. CCFs for responses to band-limited stimuli and off-line derivation of band-limited CCFs for responses evoked by broadband stimuli both showed that this technique is most sensitive to frequency-following behavior at low frequencies (less than 800 Hz). However, definite phase-locked responses to even the highest passband (3100-6200 Hz) were seen. These results support the use of the CCF technique as an efficient method of frequency-specific assessment of the auditory system.

Otitis media affects nearly every child at some time; many children have mild-to-moderate hearing losses for prolonged periods. The effects of these losses on language and educational development may be significant; possible mechanisms are discussed. Especially in suboptimal listening situations, speech perception may be impaired by even a mild hearing loss. Patterns of imperception are predicted by comparison of composite audiometric data from children with middle ear effusions with speech power data, and by analysis of sound pressure waveforms of speech filtered to simulate the typical hearing loss of these patients. A new method of analysis of brain stem evoked responses, yielding response components attributable to binaural interaction, is reported. This and other evoked response techniques may be able to identify objective changes in auditory nervous system function attributable to relative sensory deprivation during development. Finally, directions for further research in this area are discussed.

A rabbit model of endolymphatic hydrops was studied using detailed functional and cytohistologic methods. Immediately following surgical destruction of the endolymphatic sac and the distal portion of the duct, measures of the evoked auditory brainstem response (ABR) revealed mild to profound losses specific to low- and high-frequency test stimuli while responses to mid-frequency signals remained unchanged for the majority of animals. Rabbits exhibited varying degrees of vestibular upset involving both overt behavior and reduced responses to caloric stimulation. Histologic processing of the plastic embedded cochleae demonstrated distended Reissner's membranes along with extensive damage to apical and basal turn sensory cells and myelinated afferent nerve fibers while the middle portion of the cochlear duct remained relatively unaltered. An atypical pattern of hair cell lesions involving a greater loss for inner than for outer hair cells was identified at the interface between damaged apical sensorineural elements and the normal appearing organ of Corti of the middle turns.

Twenty-one consecutive patients with severe tinnitus were interviewed using a structured psychiatric interview (the National Institute of Mental Health Diagnostic Interview Schedule) and were asked to complete the Hopkins Symptom Checklist (SCL-90) and the Chronic Illness Problem Inventory. They were compared to a control group of 14 patients attending an otolaryngological clinic with a complaint of hearing loss. The tinnitus patients had a significantly greater lifetime prevalence of major depression (62% vs 21%) than controls and a significantly higher prevalence of current major depression (48% vs 7%). The currently depressed tinnitus patients had significantly higher scores on all subscales of the SCL-90, except the phobia and paranoid subscales, compared to the non-depressed tinnitus group and on all scales compared to the controls. The number of psychosocial problems and thus the resulting disability experienced was significantly greater in the tinnitus group compared to controls and in the currently depressed tinnitus patients when compared to non-depressed tinnitus patients. In view of our results treatment should aim at not only alleviation of tinnitus, but also the frequently co-existing major depression.

Noise is an environmental health problem that has not received sufficient attention. Physicians should become knowledgeable about the medical consequences of excessive noise, support legislation to reduce the problem and promote programs aimed at noise control and prevention of hearing loss. Questions about noise and hearing should be incorporated into the medical history, and pure-tone audiometry should be a part of periodic physical evaluations.

Otologic referral is an important component of an industrial hearing conservation program. Recent federal regulations in this area are reviewed, and suggestions for implementation of otologic referral are made. Criteria for otologic referral must be distinguished from a definition of significant threshold shift for internal program action. Test-retest variability is higher in industrial than in clinical settings, and unduly stringent definitions of significant threshold shift will result in many spuriously identified cases. The American Council of Otolaryngology--Head and Neck Surgery has proposed criteria for otologic referral that are probably the best available guidelines. Referrals should be made on the basis of both baseline and periodic audiometry. Most workers referred for substantial audiometric abnormalities have otologic diagnoses other than noise-induced hearing loss, or require specific intervention, or both.

An overview of some recent developments in the study of central auditory processes is presented. We describe findings from single cell physiologic studies that contribute to our understanding of central auditory function, the development of behavioral techniques permitting precise evaluation of hearing in animals, and the power and potential of integrative neurophysiologic-behavioiral investigations in defining and analyzing central neural mechanisms that underlie normal perception and imperception. The influence of changes in intermodality attention on evoked activity of 25 cells of the auditory cortex is described and compared to effects of other attentional changes. A small but consistent increase in excitatory cell evoked discharge rate and a reduction in initial latency of response are shown to be correlated with a shift from a visual to an auditory task. In general, behavioral states ranging from sleep-waking to attention to a specific acoustic cue are shown to influence responsiveness of the auditory system and variability of response. Procedures are described for effective control of attentional factors and reduction of electrophysiologic variability. The contributions of these data and procedures to studies of the encoding of complex auditory signals and studies of neural mechanisms underlying such disorders as noise induced hearing loss are discussed.

Unilateral corneal anesthesia (or hypesthesia) caused by trigeminal nerve disease has an unknown effect on the Schirmer test. Using topical anesthesia, we found that unilateral corneal anesthesia reduces tearing bilaterally, with a greater decrease on the anesthetized side. Clinicians should be aware that trigeminal nerve deficit may alter Schirmer test results, and use bilateral topical corneal anesthesia or alternative methods to stimulate tearing in these cases.

A wearable device for transcutaneous electrical tinnitus suppression (ETS) has recently been reported to be effective for relief of tinnitus. Twenty patients with sensorineural hearing loss and tinnitus participated in a double-blind crossover study. Both active devices and internally disconnected placebo devices, supplied by the manufacturer, were used. Reduction in severity of tinnitus was reported by 2 of 20 patients (10%) with the active device and by 4 of 20 (20%) with the placebo device. Fifteen of 20 (75%) had no relief with either device. Those who preferred the placebo device, however, reported only minimal relief, while one of the two who preferred the active device stated it had reduced tinnitus severity by 70% to 80%. This patient was recalled for a series of one-hour test sessions, during which either an active or placebo device was used, according to a random schedule. On each of four on trials, the score for severity of tinnitus for each ear decreased by at least 50% (median = 70%), while in three off trials, the severity of tinnitus was unchanged or decreased by up to 30% (median = 16%). We conclude that the Theraband headset is effective for a small proportion of patients with sensorineural hearing loss and tinnitus.

The assessment of worth of the neoglottic procedure has been, for the most part, subjective in nature. Evaluation by means of sequential objective measures has been developed. The following procedures are employed in our assessment: transcription intelligibility by judges unfamiliar with the passage; rate of speech; relative intensity range; intratracheal air pressure; continuous speech per breath; functional communication profile; weight status; contrast swallow study; swallow-aspiration diary; and tumor status. Data from a patient with a Staffieri neoglottis procedure illustrate the method.

Hypopharyngeal stenosis is a frequent complication of laryngectomy and radiotherapy in patients treated for carcinoma. In a retrospective study of patients treated in the University of Washington Affiliated Hospitals, hypopharyngeal stenosis was more frequent after laryngectomy with partial pharyngectomy than after laryngectomy alone and occurred more commonly in lesions of the pyriform fossa than in glottic tumors. Neck disease and inclusion of radical neck dissection were both significant factors in the development of hypopharyngeal stenosis. Recurrent tumor was significantly more prevalent in these patients.

Baseline and periodic audiometry was performed on noise-exposed workers in 21 industrial plants. Workers showing moderate hearing loss, asymmetry, or significant threshold shifts were referred for otologic evaluation. The overall referral rate was 2.76%. Of 107 referrals, 53% had otologic diagnoses other than noise-induced hearing loss, or required specific intervention, or both. The results support the use of criteria at least as stringent as those used in this study.

A technique of intracranial facial nerve anastomosis using fenestrated collagen splints was used in eight patients operated upon for acoustic neuroma or glomus temporale tumor. This technique is rapid and simpler than suturing in the cerebellopontine angle. Clinical results are as good as or even better than those obtained with more peripheral facial nerve anastomosis or grafting. An animal study demonstrated no undue histologic reaction to the collagen splints.

Symptomatic relief for hyperkinetic movements of facial musculature can be obtained by selective neurectomy of the peripheral divisions of the facial nerve with preservation of the frontal branch. Hemifacial spasm and blepharospasm represent the most common forms of facial hyperkinesia. Satisfactory results using the described technique on 191 patients were achieved in 74% of the patients with hemifacial spasm and blepharospasm in the follow-up period of one to 12 years. In hemifacial spasm, 80% were relieved after a single operation, and 95% were relieved after revision surgery. There were no major postoperative complications. Minor complications included insufficient lid closures in 1.5% of the patients and delayed wound healing with minor salivary fistulas that closed spontaneously in 7% of the patients. Resection of all fibers innervating the orbicularis oculi muscle is essential in preventing recurrence.

Carcinosarcomas are rare tumors of the upper aerodigestive tract, consisting of both carcinomatous and sarcomatous tissue. The larynx and oral cavity are most frequently involved. There has been much controversy regarding the histological nature and clinical course of these tumors. We report a case of carcinosarcoma of the floor of mouth in a 76 year old man who presented with a large pedunculated sublingual mass. There was no evidence of regional or systemic metastatic disease. After local excision, he was followed for one year without evidence of recurrence or metastasis. A review of the literature is presented, with an attempt to clarify clinically relevant aspects of nomenclature, pathogenesis, and clinical course.

Values and criteria for abnormality of the eleventh nerve evoked electromyography (EEMG) have been determined. The nerve conduction velocity and duration appear to be relatively consistent from subject to subject. Amplitude of response, while varying significantly from subject to subject, remains relatively constant when the right shoulder is compared to the left shoulder and when a retest is performed.

Frequency-following responses (FFRs) to a low-frequency stimulus in 16 normal-hearing human subjects were cross-correlated with the stimulus in an attempt to yield more easily recognizable FFRs at lower intensity levels and increase threshold sensitivity. Cross-correlation of these responses with the stimulus did not improve threshold sensitivity and latencies obtained from the cross-correlated FFRs showed more variability and were uniformly shorter than those of standard FFR measurement.

Baseline and periodic audiometry was performed on noise-exposed workers in 21 industrial plants. Workers showing moderate hearing loss, asymmetry, or significant threshold shifts were referred for otologic evaluation. The overall referral rate was 2.76%. Of 107 referrals, 53% had otologic diagnoses other than noise-induced hearing loss or required specific intervention, or both. The results support the use of criteria at least as stringent as those used in this study.