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Updated: Aug 19, 2026
Data Acquisition and Analysis In Brainstem Evoked Response Audiometry In Mice
Published on: May 10, 2019
The progress of adrenoleukodystrophy as revealed by auditory brainstem evoked responses and brainstem histology
Insights
Adrenoleukodystrophy caused progressive hearing loss and auditory brainstem response (ABR) changes in a child. Postmortem findings confirmed demyelination and neuronal loss in auditory pathways, indicating brainstem degeneration.
Area of Science:
- Neurology
- Pediatrics
- Neurophysiology
Background:
- Adrenoleukodystrophy (ALD) is a rare genetic disorder affecting the nervous system.
- Early diagnosis and monitoring of neurological deficits are crucial in ALD management.
Observation:
- Serial auditory brainstem evoked responses (ABR) and slow vertex responses (SVR) were monitored in a 6-year-old boy with ALD.
- The child presented with gait disturbance, dysarthria, hearing difficulty, progressing to spastic paralysis, deafness, and blindness.
Findings:
- ABR showed initial normal responses, evolving to abnormal patterns with prolonged interpeak intervals and loss of later components.
- Terminal ABR revealed only a prolonged wave I, correlating with severe auditory pathway degeneration.
- Postmortem examination confirmed demyelination of auditory nerves and neuronal loss in brainstem auditory pathways, alongside widespread cerebral degeneration.
Implications:
- Serial ABR can track the progression of auditory pathway involvement in ALD.
- Findings suggest a rostral to caudal pattern of brainstem degeneration in this pediatric ALD case.
- Understanding the neurophysiological changes aids in comprehending ALD's impact on sensory pathways.
Abstract:
Serial studies of auditory brainstem evoked responses (ABR) and slow vertex responses (SVR) were obtained during the progress of adrenoleukodystrophy in a 6-year-old boy. This child was normal until 5 years of age. His illness began with a gait disturbance, dysarthria, and hearing difficulty. Later, spastic paralysis, serious deafness, and blindness appeared. He died of respiratory failure 2 years after the onset. The ABR was normal at onset but changed to an abnormal pattern. Initially, there was lengthening of the wave V-I interpeak interval. This was followed by the disappearance of the later components as his general condition deteriorated. At the terminal stage, only a prolonged wave I was recordable. The postmortem pathology revealed demyelination of auditory nerves and remarkable neuronal loss in the auditory pathways of the brainstem; in addition, there was a variety of extensive degeneration throughout the cerebrum, in particular the complete degeneration of the white matter with secondarily occurring ganglionic cell changes. These date suggest that degeneration of the brainstem from rostral to caudal levels occurred.
