Stimulus repetition rate effect on the auditory brainstem response in systemic lupus erythematosus.

Neuropsychiatric involvement is common in systemic lupus erythematosus (SLE), but, in early half of cases, indications are not present on examination. Auditory brainstem response (ABR) measures using differential stimulus repetition rates have been reported as sensitive indicators of subclinical central nervous system (CNS) disorders associated with SLE. In the present study, ABRs were measured in a group of normal-hearing subjects with SLE, as well as in a group of subject controls. Differences in interpeak latency (IPL) measures obtained using low- and high-stimulus repetition rates did not reach statistical significance (P greater than .05). Clinical utility of ABRs using high- and low-stimulus repetition rates for the identification of occult CNS disorder in patients with SLE was not demonstrated.

Insert earphones for audiometry: applications, advantages, and limitations.

The measurement of hearing sensitivity during audiometry requires precise presentation of auditory stimuli. In most cases, these stimuli are introduced to the listener via standard earphones. Technical problems associated with these earphones have troubled clinicians for years. An alternative earphone system for audiometry was introduced that uses shoulder-worn transducers with inserts for connection with the external auditory canal. Although insert earphones are not intended to supplant standard earphones, experimental evidence and clinical observations support the advantageousness of these earphones under a variety of clinical conditions.

Clinical applicability of insert earphones for audiometry.

Insert transducers for audiometry are available which may offer significant advantages over older 'standard' headphones. Clinicians have remained cautious in using such devices due to the paucity of experimental data demonstrating their comparability with more widely used devices. The purpose of this investigation was to compare and contrast pure-tone audiometric thresholds obtained using insert earphones with those measured utilizing conventional supra-aural transducers in normal and hearing-impaired subjects. A second purpose was to examine the differential effects on the hearing threshold level of two coupling systems for the insert device. There were no clinically significant differences among pure-tone thresholds measured with the three earphone/coupler arrangements for subjects with normal and impaired hearing. Advantages and limitations of insert earphones are discussed.