Malden wrote:I am monitoring this forum, CCVCI theory, etc, about two months and didnt find any logical reason to support this theory and procedures to my half, still functional part of the brain.
Best regards, M.
cheerleader wrote:...Blocked veins can create slowed perfusion, and slowed mean transit time. The longer it takes deoxygenated blood to get out, the longer it takes oxygen to get in....
Malden wrote:Blocked veins can't create slower perfusion.
Perfusion is the process of nutritive delivery of arterial blood to a capillary bed in the biological tissue. No veines involved.
Only hart-arteria-arteriola-capillary and then delivery.
Decreased Pulmonary Perfusion in Pulmonary Vein Stenosis After Radiofrequency Ablation*
Assessment With Dynamic Magnetic Resonance Perfusion Imaging
Conclusions: PVSs caused severe perfusion deficits, which were reliably demonstrated by MR perfusion imaging.
Regional enhancement differences that reflect the hemodynamic disturbance in the liver in patients with Budd-Chiari syndrome have been already known from observations on contrastenhanced CT . Nonenhancement is an indicator of hypoperfusion, and hypoperfused regions are prone to severe damage due to anoxia.
Hypoperfusion of Brain Parenchyma Is Strongly Associated with the Severity of Chronic Cerebrospinal Venous Insufficiency in Patients with Multiple Sclerosis.
OBJECTIVE: To investigate the relationship between chronic cerebrospinal venous insufficiency (CCSVI) and cerebral perfusion in patients with multiple sclerosis (MS). BACKGROUND: CCSVI is a vascular condition described in MS patients, characterized by stenoses of the main extracranial veins with hampered cerebral venous outflow. We hypothesized that the impaired venous outflow contributes to hypoperfusion of brain parenchyma. DESIGN/METHODS: Sixteen consecutive relapsing-remitting MS patients (mean age 36.1yrs, mean disease duration 7.5yrs and median EDSS 2.5) and 8 age- and sex-matched normal controls (NC), were scanned on a GE 3T scanner using dynamic susceptibility contrast enhanced perfusion-weighted imaging (PWI). Cerebral blood flow (CBF), blood volume (CBV) and mean transit time (MTT) were measured in the gray matter (GM), white matter (WM), normal appearing (NA) GM, NAWM, thalamus, caudate, putamen, globus pallidus, hippocampus, amygdala, nucleus accumbens, red nucleus and substantia nigra. Diagnosis of CCSVI was established based on the venous hemodynamic (VH) Doppler criteria (Zamboni, JNNP, 2009) and the severity was based on fulfilled VH criteria (score 0-5) and VH insufficiency severity score (VHISS) (score 0-16). RESULTS: All 16 MS patients fulfilled the diagnosis of CCSVI (median VH=4, median VHISS=9) and none of the NC. There was a significant association between VH criteria and VHISS, and CBF, CBV and MTT in all examined regions of the brain parenchyma in MS patients. The most robust correlations were observed for lower CBF and higher VHISS in the GM, WM, NAGM and NAWM (r= -0.70 to -0.72, p<0.002), and in the thalamus, caudate, putamen, hippocampus, nucleus accumbens (r= -0.6 to -0.72, p<0.008). The correlation coefficients for CBV and MTT were in a range between r= -0.5 to -0.65. No relationship was observed for NC. CONCLUSIONS/RELEVANCE: This study demonstrates that severity of CCSVI is directly associated with hypoperfusion of the brain parenchyma in MS. Supported by: Hillarescere Foundation and Buffalo Neuroimaging Analysis Center.
cheerleader wrote:Veins are involved in perfusion.
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