Introduction. Landau-Kleffner Syndrome is characterized by normal speech acquisition followed by epileptic seizures, receptive and expressive language deterioration coupled with agnosia for non-verbal sounds, having variable long-term evolution. Case Report. It is described neurophysiologic and acoustic findings in a patient with Landau-Kleffner Syndrome, and correlate these with the results of a language evaluation carriedout 7 years after the acute phase. It is performed Electroencephalography, Immitance Measurements, Basic Audiometry, Auditory Brainstem Response, Middle Latency Response, and P300. Language was evaluated by Boston Diagnostic Aphasia Examination. Electroencephalography was normal and audiologic evaluation revealed normal Immitance Measurements, Basic Audiometry and Auditory Brainstem Response values. Anelectrode effect was present in the left hemisphere in Middle Latency Response, and bilateral P300 latencies delayed on the right. Language evaluation showed severe receptive and expressive impairment, severe phonemic substitutions, which had an impact on social and academic levels. There were contextual and gestual non-verbal compensations, evidencing intellectual and cognitive domain preservation. Conclusion. This case illustrates the specific cerebral areas that can be damaged in patients with Landau-Kleffner Syndrome and which are demonstrable by clinical evaluation and proper neurophysiology studies, showing the importance of neurological, audiological, electrophysiological and language exams in a longitudinal follow up.
Signal processing method for data with simultaneous recording of auditory brainstem response, middle latency response, and slow vertex response
