The following two images of the same page, viewed on different montages, illustrate the problem discussed in the previous post,  emphasising rule 2.

in the image above, while the patient ...

This can be tough. Really tough. Rule of thumb? Don't call them spikes if they appear in 1 electrode only! There are exceptions. But be very careful. Even worse, artefacts can appear in adjacent elect...

It may sometimes be hard to tell cortical abnormalities from artefact. Have a look at this:

Referential montage

In the above, T5 (A17) appears artefactual. Hence, one may assume all abnormal...

The patient is five years old. These are best seen on referential montages, where they may be confused with a train of sharp waves or even electrographic seizures; hence they are regarded as "pseudo-e...

An early Sunday morning call from the emergency unit medical officer working at a nearby hospital concerns the issue of a white cell count of 19 (81% polys & 11% lymphs) and a CRP of 14 in a patient, ...

One can certainly see spikes in one electrode. However, this is an uncommon phenomenon and more often than not a sharply-contoured wave or a spike-and-wave-like discharge is an electrode artifact. Hav...

There are plenty of discharges on an EEG that mimic seizures and many of these are simply normal physiological relevance, either while awake or asleep. Believe it or not, but sometimes "focal" seizure...

At the age of 7 years the patient developed absence seizures, with innumerable daily events characterized by brief episodes of staring and unresponsiveness, without warning and without any post-ictal ...

If this problem vexes you at times, be assured that you are not alone. The distinction between these on morphology alone is often impossible. The former in the title raises the possibility of encephal...

Here are a few more wicket waves. The patient is 52 years old and likely has left temporal lobe epilepsy, with a normal MRI scan.

 In the above, the patient is asleep. Notice the low amplitude i...