Fig. 20. Light micrographs showing morphology of en plaque (bottom, labeled A) and en grappe (top) neuromuscular junctions in human extraocular muscle. The en plaque endings are sometimes lobulated. Rarely, two terminals occur on muscle fiber, as illustrated here. En grappe endings contain multiple, small, oval disks spread along a single muscle fiber. (Cheng K: Cholinesterase activity in human extraocular muscles. Jpn J Ophthalmol 7:174, 1963.)