Generalized Myoclonic Seizures

Myoclonic seizures were elegantly described in the nineteenth century by prominent French, English, and German neurologists. The history is detailed in Inoue et al. (2008). During the latter part of the twentieth century, as pediatric epilepsy syndromes were delineated, it became apparent that myoclonic seizures could be found in both benign and severe settings. Generalized myoclonic seizures are covered in this section, but the term generalized does not necessarily imply total body involvement. Rather, the myoclonic activity may be limited to just certain regions, such as proximal limbs or trunk in a more or less symmetric fashion.

Definition

The ILAE glossary defines myoclonus as “sudden brief (<100 ms) involuntary single or multiple contraction(s) of muscle(s) or muscle group of variable topography (axial, proximal limb, distal)” (Blume et al. 2001).

Classification

Myoclonic seizures may be focal or generalized. This section focuses on generalized myoclonic seizures.

Clinical...