[Nimodipine and cerebrovascular circulation. Initial results apropos of 4 cases of subarachnoid hemorrhage]. / Nimodipine et vascularisation cérébrale. Données préliminaires à propos de quatre observations d'hémorragie méningée.

Nimodipine was included in the treatment of four patients who had previously presented subarachnoid hemorrhage; cerebral circulation has been assayed by means of "Tomophygmographie cérébrale ultra-sonore". In all four patients, use of Nimodipine has led to an improvement of cerebral circulation and then of the neurological status. Nimodipine is characterized by its very low therapeutic inertion. Data obtained both at the initiation and on interruption of the administration of this drug points to its original properties regarding cerebral circulation: indeed, the present observations suggest that Nimodipine behaves as a true vasoregulator.

[Early brain stem auditory evoked potentials in brain death]. / Potentiels evoques auditifs précoces du tronc cérébral dans la mort cérébrale.

Brain-stem auditory evoked potentials (BAEPs) are realized after the first flat EEG in 50 patients. BAEPs were absent in 70% of the patients. In 22% of the patients, one- or two-sided peak I persists. In 8% the peaks I, II and IV exist after the first flat EEG. BAEP evolution with the course of time is realized. A complete disappearance is established after 24 h. The useful advantage of BAEPs in the early diagnosis of brain death is discussed.

[Pulsatile echography (ultrasonic cerebral tomosphygmography) in carotid and vertebral pathology. Surgical applications]. / L'échographie pulsatile (tomosphygmographie cérébrale ultrasonore) en pathologie carotidienne et vertébrale. Applications chirurgicales.

Ultrasonographic cerebral tomosphygmography (U.C.T.S.) is a method for determining cerebral pulsatility by centimeter-thick sections. The prototype uses a 2 MHz ultrasound wave emitted in the direction of cerebral structures. The reflected wave is captured by centimeter-thick sections, the mean determined and a pulsatile index defined. This index varies according to the regions studied (cortico-subcortical, superficial sylvian, deep sylvian and vertebrobasilar). Physiologic pulsatility was determined from a series of 150 healthy subjects. This technique was used to evaluate effects of carotid and vertebral circulation revascularization in 21 patients. Findings showed lack of relation between anatomic lesion and cerebral pulsatility, absence of significant modification of the index after release of carotid occlusion except when postoperative thrombosis occurred, and heterogeneous individual behavior after revascularization distinguishing subgroups of indifferent (40%), improved (27%), hyperpulsatile (27%) and worsened (13%) subjects. Two patients presented worsening on the contralateral side compatible with a steal syndrome. Results suggest that U.C.T.S. is a promising method of preoperative investigation and postoperative surveillance of carotid artery stenosis.