A prospective evaluation of phrenic nerve conduction in multifocal motor neuropathy and chronic inflammatory demyelinating polyneuropathy.
The purpose of the study was to evaluate electrophysiologically phrenic nerve involvement in multifocal motor neuropathy (MMN) and chronic inflammatory demyelinating polyneuropathy (CIDP). The response latencies following phrenic nerve stimulation were increased in 11 of 14 (80%) patients in the CIDP group but in only 1 of 14 (8%) patients in the MMN group. The mean diaphragmatic compound muscle action potential (CMAP) was significantly lower in amplitude in the CIDP group compared to the MMN group and to a control group of 8 subjects (P < 0.001). There were no significant differences between the MMN and control groups. Only the reduction in CMAP amplitude correlated with the presence of restrictive lung function. Phrenic nerve conduction measurement should be performed more systematically, especially in CIDP and, when diaphragmatic CMAPs are reduced in amplitude, pulmonary function tests should be performed to look for a restrictive lung syndrome.
Macia
Frederic
F
Department of Neurology, Hôpital Haut-Lévèque, Avenue de Magellan, 33604 Pessac, France.
Le Masson
Gwendal
G
Rouanet-Larriviere
Marie
M
Habonimana
Desire
D
Ferrer
Xavier
X
Marthan
Roger
R
Lagueny
Alain
A
D000328:Adult; D000368:Aged; D003964:Diaphragm / Q000294:innervation / Q000503:physiopathology; D004558:Electric Stimulation; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000150:complications* / Q000503:physiopathology; D009431:Neural Conduction / Q000502:physiology; D010791:Phrenic Nerve / Q000503:physiopathology*; D020277:Polyradiculoneuropathy, Chronic Inflammatory Demyelinating / Q000150:complications* / Q000503:physiopathology; D011446:Prospective Studies; D011930:Reaction Time / Q000502:physiology; D012120:Respiration Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D012129:Respiratory Function Tests