EEG Sample: The Learning EEG (learningeeg.com)
Text Resources: Greenfield, John, L. et al. Reading EEGs: A Practical Approach. Available from: Wolters Kluwer, (2nd Edition). Wolters Kluwer Health, 2020.
Triphasic waves are a three-phase complex consisting of negative-positive-negative polarity in the delta/theta frequency ranges and a high amplitude. This pattern can be generalized or lateralized, often maximally frontal with an anterior to posterior lag (AP gradient). Triphasic waves appear synchronous with a periodic or pseudo periodic occurrence. Typically seen in obtunded or stuporous patients with impaired consciousness, associated with encephalopathy. The pattern was first reported as a specific pattern of hepatic encephalopathy, over time it has become a recognizable pattern metabolic, toxic and anoxic encephalopathies, reflective of a diffuse cerebral dysfunction.
Question:
What degenerative central nervous system (CNS) disease is this EEG pattern indicative of, generally present after the first 2 months of clinical symptoms that include rapidly progressive dementia and myoclonus?
Results
#1. What degenerative central nervous system (CNS) disease is this EEG pattern indicative of, generally present after the first 2 months of clinical symptoms that include rapidly progressive dementia and myoclonus?
The classic clinical symptoms of CJD are rapidly progressing dementia and myoclonus. Ataxia, visual symptoms, and akinetic mutism are often present as well.
Creutzfeldt-Jakob disease (CJD) is the most common human prion disease. The EEG shows clinicians a key indicating pattern important in the diagnosis process. Typical EEG findings include bi-anterior dominant periodic triphasic sharp wave complexes, lasting 600-1000ms, occuring at a rate of 0.5 to 2Hz. These complexes can be purely unilateral in early stages of the disease of CJD. During the late stages of CJD myoclonus is common.
