Low-rate nerve stimulation during regional ischemia in the diagnosis of muscle glycogenosis.
Five patients with muscle glycogenoses (Gly), 30 normal subjects (NS), and 52 disease controls received 3 Hz repetitive stimulation of the ulnar nerve for 4 min (P-LRNS) during regional ischemia and during normal circulation. During regional ischemia, the compound muscle action potential (CMAP) of NS showed 8.5% (SE: 1.0) facilitation after 1 min of P-LRNS and 4.8 +/- 1.5% facilitation after 4 min. Gly showed 8.1 +/- 1.0% facilitation after 1 min of P-LRNS but -58.6 +/- 6.9% depression after 4 min of P-LRNS. During normal circulation, in 18 NS and 4 Gly tested, the facilitation detected after 1 min of P-LRNS was unchanged until the end of stimulation. Compared with the mean +/- 2 SD of NS, individual values of CMAP depression were abnormal in all Gly patients already by the 3rd min of ischemic P-LRNS. Of disease controls, myasthenia gravis patients only showed a CMAP depression during ischemic P-LRNS which was distinguishable from that detected in Gly, being mainly induced by neuromuscular transmission block.
Lomonaco
M
M
Department of Neurology, Università Cattolica del Sacro Cuore, Rome, Italy.
Milone
M
M
Valente
E M
EM
Padua
L
L
Tonali
P
P
D000200:Action Potentials; D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003250:Constriction; D004558:Electric Stimulation / Q000379:methods; D005260:Female; D006008:Glycogen Storage Disease / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000098:blood supply*; D009135:Muscular Diseases / Q000175:diagnosis*; D009157:Myasthenia Gravis / Q000175:diagnosis; D009468:Neuromuscular Diseases / Q000175:diagnosis; D012016:Reference Values; D012039:Regional Blood Flow; D013997:Time Factors; D014459:Ulnar Nerve