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Auditory brainstem response (ABR) and middle latency evoked response (MLER) testing have been used successfully for assessing hearing sensitivity electrophysiologically. Though both procedures have their proponents, ABR seems to be the more popular of the two. However, this study shows that overall, MLER waves occur with greater frequency at low sensation level than ABR waves. Specifically, MLER wave Pa was the most sensitive wave, followed by ABR wave V, MLER wave Pb, ABR wave III, MLER wave Pc, and ABR wave I. Latencies were more consistent and predictable for ABR than MLER. However, as expected, amplitudes for MLER wave were greater than those for ABR. Given these results, those involved in measuring hearing sensitivity electrophysiologically are encouraged to consider the potential of the MLER measure and not limit their scope of assessment to ABR.

For many years (auditory) middle latency response (MLR) reportedly has been an excellent electrophysiological procedure for estimating frequency specific auditory thresholds. Currently the 40 Hz potential, a derivative of the MLR, holds even greater promise for threshold testing. MLR also appears to have potentially valuable applications in the evaluation of functional hearing loss and assessment of higher auditory function. However, MLR is not without controversy. Questions of origin, filtering effects, and its use in pediatric assessment are current issues surrounding applications of MLR. The following article analyzes the values and limitations of MLR within the framework of past, present, and future research and clinical uses.

A review of salient features in the use of auditory brainstem response for the detection of eighth nerve lesions is presented. Three cases of acoustic tumors are discussed. These cases represent a normal pure-tone audiogram, one with a moderate loss, and one with no measurable hearing on the affected side. Interpretation of the auditory brainstem response in these cases is discussed in light of the various auditory brainstem response measures presented and the pure-tone audiometric data.

Twenty-five patients with stage III or IV locally advanced head and neck cancer were treated from February 1981 to November 1982 with a combined modality approach utilizing chemotherapy followed by irradiation and surgery. Induction therapy with cisplatin and bleomycin was followed by a sequence integrating weekly cisplatin into a program of locoregional irradiation. After the administration of 4800 cGy, patients received either "boost" irradiation or surgery. At the completion of all therapy, 20 of 23 patients evaluable for response had achieved complete remission. Toxicity was tolerable and all patients are being followed closely to assess durability of remission and overall survival.

Sixteen patients with confirmed mass lesions of the posterior fossa and normal hearing sensitivity for pure tones were studied. Patients' main symptoms, auditory brain-stem response (ABR), and lesion size were analyzed. All patients manifested neurologic and/or otoneurologic symptoms or complained of hearing difficulty disproportionate to their pure-tone findings. Interestingly, the patients in this select group were younger (mean = 34 years) than the typical patient with a posterior fossa tumor. ABR results were abnormal in 15 of the patients, although several indices--including absolute and interwave latencies, interaural latency difference, and wave presence/absence--were employed to achieve this sensitivity. Lesion size varied considerably and failed to correlate with ABR or pure-tone results.

A patient with a large, right-sided basilar artery aneurysm was evaluated. Major symptoms included progressive hearing loss, facial numbness, occipital headaches, dizziness, and diplopia of less than a year's duration. Audiologic results indicated a low-frequency sensorineural hearing loss with marked discrepancies between ascending and descending pure-tone thresholds for the ear ipsilateral to the lesion. Auditory brain-stem response demonstrated bilateral abnormalities, but the early waves were normal. Contralateral acoustic reflexes were absent on the right and elevated on the left. Electronystagmography results showed bilaterally absent caloric responses as well as gaze nystagmus and abnormal pursuit movements. Additional audiologic results as well as radiologic and medical findings are also presented.

The aim of this study was to describe the anatomical limits of a wedge shaped area of bone lying posterior to the internal auditory canal and to describe the anatomical structures which course through it. One hundred consecutive temporal bones were dissected and topographical dimensions of the posterior wall of the temporal bone were measured along with depth measurements from the posterior fossa wall to the structures of the fundus of the internal auditory canal. A microsurgical technique was then described using the structures within this area as landmarks for specific dissection to the posterior and lateral aspects of the internal auditory canal. Results of 19 tumors have been presented. The status of the facial nerve at the end of surgery and whether or not total tumor removal was possible were discussed.

Spontaneous cerebrospinal fluid (CSF) otorrhea implies the observation of CSF draining from the ear or nose without any previous history of traumatic or infectious etiology. The term does not exclude embryologic or developmental abnormalities. The condition may be life-threatening. Thus far it has been reported about twenty times. Because it is rare, misdiagnosis or failure to make a timely early diagnosis is common and proper therapy may be delayed. The purpose of this article is to review pertinent literature on this subject and to present two additional case reports. Emphasis will be placed on accuracy of diagnosis and on the surgical technique employed in repair of the discovered defect.

Five cases of children with auditory processing problems are presented. These children had essentially normal peripheral hearing and ENT exam, but were referred with a question of hearing loss. An auditory perceptual test battery including rapidly alternating speech (RASP), binaural fusion, low pass filtered speech (LPFS), competing sentences, staggered spondiac words (SSW), dichotic digits and frequency patterns was employed. Though some of these tests did not show a perceptual deficit, the majority did depict specific types of auditory processing problems. Based on the information provided by this test battery, appropriate diagnosis and therapy can be provided for the patient.

A variation of the pectoralis major myocutaneous flap in head and neck reconstruction is presented. The defect to be covered was a large, intraoral, U-shaped defect extending from the left tonsillar region around the alveolar ridge and floor of mouth to the right soft palate and buccal mucosa. Nearly the entire tongue was intact, and a 4 cm left mandibular segmental defect existed. A single left pectoralis major myocutaneous island flap was split longitudinally to resurface the defect. Implications of vertical splitting of a myocutaneous flap are discussed with respect to blood supply and limits.