Studies of the Cerebral Circulation with Labeled Erythrocytes in Healthy Man

Abstract

A thorough investigation of 10 healthy males, 26 to 46 years old, has been performed. One and a half ml. of their own erythrocytes, labeled with P 32 , was injected intravenously and dilution curves obtained simultaneously from one carotid artery and the two jugular bulbs. Thereafter, the same amount of labeled blood was injected into both carotid arteries, following one another, and dilution curves from the two jugular bulbs were simultaneously obtained. A total of seven dilution curves was collected in each case. The percutaneous punctures of the carotids were high enough in the neck so that it is highly probable that the injections were made into the internal carotid arteries. Calculations of the cerebral blood flow and the cerebral blood volume in absolute values were performed. The mean value of the cerebral blood flow amounted to 876 ml/min., i.e., 11.4 per cent of the cardiac output. The pool of the brain was calculated to about 100 ml. When a carotid artery was injected, the appearance and peak concentration times estimated from the dilution curves obtained from the ipsilateral bulbs were the same whether the injection was performed in the right or left side. The corresponding times for the dilution curves obtained from the contralateral bulb agreed, whichever the side on which the injection was performned. They were, however, one second longer than the ipsilateral ones. The determination of circulation time is of diagnostic value, according to an earlier publication. A simplified bloodless method has also been tried.

Extrajugular pathways of human cerebral venous blood drainage assessed by duplex ultrasound

“…The IJVs have been considered to present the most important pathway for venous blood returning from the brain. This assumption was based on angiographic studies and cerebral blood flow analyses with nitrous oxide, labeled erythrocytes, and thermodilution techniques (12,21,15,25), which were all performed in a supine body position. However, anatomic investigations as well as clinical observations in patients after bilateral radical neck dissection suggest coexisting IJV-independent alternative venous drainage pathways (9).…”

Impact of Cerebral Microcirculatory Changes on Cerebral Blood Flow During Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage

“…CCT has formerly been evaluated by using radioisotope and extracranial counting 26,27 ; however, it was not feasible for routine clinical use. Recently, CCT has been obtained by analyzing the time-density curve on DSA images and has usually been represented as MTT at ROI.…”

Color Doppler sonographic evaluation of flow volume of the internal carotid and vertebral arteries after carotid endarterectomy

“…25 Nylin et al used P-labeled erythrocytes in healthy men. 26 Since then, many methods have been used for this measurement including the single-photon emission computerized tomography, 27 or positron emission tomography, MRI, 28 and CDUS. Singlephoton emission computerized tomography and positron emission tomography are able to assess the regional CBFV, whereas Doppler US can only assess the relative contribution of the ICA and VA.…”