DEFECATORY DISORDERS IN DE-NOVO PARKINSONIANS - COLONIC TRANSIT AND ELECTROMYOGRAM OF THE EXTERNAL ANAL-SPHINCTER

Constipation is very common in Parkinson's disease. it is still not kn own whether constipation is due to a slow transit of the colon or an o utlet obstruction. We examined 25 patients (11 women, 14 men, mean age 62 years) with newly diagnosed idiopathic Parkinson's disease. All pa tients had typical clinical symptoms (with an average score of 11.4 po ints on the Webster scale); the diagnosis was confirmed by F-18-Dopa-P ET. in all patients the colon transit time was measured with radioopaq ue markers. Pudendal nerve lesions were excluded by neurography of the pudendal nerve. Electromyography of the external anal sphincter was p erformed with concentric needle electrodes in the right and left later al position. Colon transit time in the patients averaged 3.7 days, wit h pathologically prolonged transit (> 4 days) in 6 patients (24%). Fou r patients (16%) showed mild neurogenic changes on sphincter EMG (16%) . In three other cases (12%) long duration and large amplitude of moto r unit action potentials (MUAPs), and a reduced interference pattern d uring maximal voluntary effort indicated a severe neurogenic lesion. O ne patient presented with involuntary contractions of the external ana l sphincter at rest, which increased during strain (anism).