Which EEG pattern is NOT the result of cerebral anoxia?

The choice identifying phantom spike waves as the EEG pattern that is not a result of cerebral anoxia is correct because this pattern is often associated with conditions like epileptic discharges rather than anoxic events. Phantom spike waves, characterized by high-frequency, sharp waves that may not correspond to any structural pathology, can occur due to cortical irritability or might be seen in certain types of epilepsy, particularly in states of alertness or cortical dysfunction not directly tied to a lack of oxygen.

In contrast, burst suppression, electrocerebral inactivity, and alpha coma are all associated with significant cerebral impairment or anoxia. Burst suppression denotes a pattern of alternating periods of high-voltage bursts and flat periods, often seen in patients with severe brain damage or during deep anesthesia. Electrocerebral inactivity indicates a flat EEG, signifying a complete lack of electrical activity, commonly observed in profound hypoxia or brain death. Alpha coma involves the presence of alpha activity in a comatose patient and can also be indicative of brain dysfunction related to metabolic disturbances, which may include anoxic conditions. Thus, the other patterns directly reflect states of reduced or compromised cerebral function due to anoxia.