D Greitz1, J Hannerz. 1. Department of Neuroradiology, Karolinska Hospital, Stockholm, Sweden.
Abstract
PURPOSE: To determine the mechanisms of the tracer distribution at radionuclide cisternography (RC). METHODS: Ten patients with venous vasculitis were studied with RC. Flow phantom studies were performed mimicking cerebrospinal fluid (CSF) circulation with and without a main outlet comparable to the pacchionian granulations. RESULTS: Nine of the 10 patients had normal findings on RC images, including a maximum uptake over the vertex at 24 hours. In all patients, a second maximum occurred in the lumbosacral area. The flow phantom studies showed no tracer accumulation at an open outlet corresponding to the pacchionian granulations. On the contrary, a maximum arose without such an outlet. A maximum always arose at the closed dead ends of the phantom, including the lumbosacral area. CONCLUSION: The commonly accepted flow model for CSF circulation needs to be revised. The pattern of the normal RC cannot be explained by a bulk flow transport of the tracer to an outlet at the pacchionian granulations but rather by a primary mixing caused by pulsatile flow with a secondary dilution by newly formed CSF from the ventricular system. We suggest that the main absorption of the CSF is through the central nervous system to the blood.
PURPOSE: To determine the mechanisms of the tracer distribution at radionuclide cisternography (RC). METHODS: Ten patients with venous vasculitis were studied with RC. Flow phantom studies were performed mimicking cerebrospinal fluid (CSF) circulation with and without a main outlet comparable to the pacchionian granulations. RESULTS: Nine of the 10 patients had normal findings on RC images, including a maximum uptake over the vertex at 24 hours. In all patients, a second maximum occurred in the lumbosacral area. The flow phantom studies showed no tracer accumulation at an open outlet corresponding to the pacchionian granulations. On the contrary, a maximum arose without such an outlet. A maximum always arose at the closed dead ends of the phantom, including the lumbosacral area. CONCLUSION: The commonly accepted flow model for CSF circulation needs to be revised. The pattern of the normal RC cannot be explained by a bulk flow transport of the tracer to an outlet at the pacchionian granulations but rather by a primary mixing caused by pulsatile flow with a secondary dilution by newly formed CSF from the ventricular system. We suggest that the main absorption of the CSF is through the central nervous system to the blood.
Authors: W Coenen; C Gutiérrez-Montes; S Sincomb; E Criado-Hidalgo; K Wei; K King; V Haughton; C Martínez-Bazán; A L Sánchez; J C Lasheras Journal: AJNR Am J Neuroradiol Date: 2019-06-13 Impact factor: 3.825
Authors: Ryan Gene Soderquist; Evan M Sloane; Lisa C Loram; Jacqueline A Harrison; Ellen C Dengler; Scott M Johnson; Luke D Amer; Courtney S Young; Makenzie T Lewis; Stephen Poole; Matthew G Frank; Linda R Watkins; Erin D Milligan; Melissa J Mahoney Journal: Pharm Res Date: 2010-03-12 Impact factor: 4.200