CCSVI doppler diagnostics presented at vascular conference
January 4, 2013 at 2:09pm
The 34th Congress of the SIAPAV (Italian Society for Angiology and Vascular Medicine) http://www.siapav.it had an extensive review session of CCSVI diagnostics.
There were three lectures presented by specialists in doppler ultrasound for CCSVI. All of these specialists agree that CCSVI exists, it creates a delay of cerebral blood flow, hypoperfusion, and cerebral lesions, and there are very specific tests to measure this process.
The specialists also stated that operators who are finding between 0-50% of CCSVI in people with MS are NOT utilizing correct doppler technique. They stated that the SAME problem happened 35 years ago, when technicians began analysing the carotid arteries. There is a very specific protocol that must be followed, or the results are inaccurate. A lack of knowledge of the venous return system from the brain is part of this problem.
The fact that neurologists continue to ignore this clarion call from vascular specialists, and proceed with badly designed studies, is disturbing. There have been millions of dollars of wasted money and years of wasted time, pursuing studies that are of no value.
Below is the very specific review from this conference.
It is translated by google translate from Italian, and because if this, is not perfect. But BNAC offers training for American doppler technicians, based on this protocol. BNAC is the only center with a published US study that has worked with the experts in this doppler protocol. None of the NMSS funded researcher utilized the complete and correct protocol.
Refresher Course of the 34th Congress SIAPAV dedicated to CCSVI has provided an extensive updating on the diagnosis of chronic cerebrospinal venous insufficiency. The report that follows is intended as a reference for those interested in the clinical picture characterized by hemodynamic abnormalities and / or abnormalities of the refluxing veins from the Central Nervous System.
Three lectures were devoted to the physiology and pathophysiology of cerebral venous return (M. Mancini, Naples), which is essential for understanding the clinical phenomena, paintings echo-color-Doppler normal and pathological (G. Cacciaguerra, Catania), prerequisite for obtaining a correct diagnosis, limiting as much as possible the false negative and false positive and, finally, to the diagnostic protocol with the main criteria and / or accessories must be based on which the diagnosis (G. Arpaia, Vimercate).
Mancini has outlined the salient features of venous hemodynamics in the brain, illustrating the intracranial circulation time measured with echo contrast (landmarks carotid artery, jugular vein and thyroid) that are significantly delayed in CCSVI. From the point of view the speaker presented the map of cerebral perfusion and the prevalence of MS plaques in the hypoperfused areas in the form of clinical progressive MS, while the prevalence in areas hypoperfused would be greater in relapsing-remitting clinical form. This could explain the greater effectiveness of the correction hemodynamics in relapsing-remitting MS, compared to progressive MS.
Cacciaguerra revised the pathophysiology of cerebrospinal venous return defining the echo-color-Doppler scans as normal, so you can have a reference model for the faulty diagnosis of CCSVI.
From the hemodynamic point of view the cerebral is a system with high flow and low capacity (total content of blood about 150 ml), allocated inside a bony structure not dilatable, devoid of valves, with the venous return regulated almost exclusively by pressure gradients. It is sensitive to changes in posture and can not escape the laws hemodynamic general, first of all the equivalence between arterial inflow and venous outflow. On the contrary, the spinal cord is a high-capacity system (total content of blood variable from 200 to 1000 ml). The two systems represent a unique hemodynamic, with the second resevoir that serves as the first.
In the jugular veins, venous flow largely reflects the intracranial flow, is governed by the face to the back and the intracranial pressure, is synchronous with heart activity, mainly in one direction, and varies with the change of position and rotation of the head.
In the vertebral veins, the flow is similar to that jugular, but with postural inverse behavior. Communicate directly with the intracranial venous sinuses, and is connected with the vertebral venous plexus.
In the petrosal sinuses and spinal cord, venous flow is not affected by face-to-back and only the activity is called respiration.
According to this model hemodynamic reference CCSVI can be defined as a loss of temporal variability and postural drainage, with de-synchronization of the venous return and the formation of vicious circles (reflux) and system overload capacitive spinal cord.
Arpaia has illustrated clearly the diagnostic echo-color along the lines indicated by the consensus document of 2011 [Int Angiol. 2011 30 (6) :571-97), starting with the precise identification of landmarks (Table 1).
Table 1 - Reference points for the study ECD CCSVI Jugular veins Observation projection transverse and longitudinal in three points, exerting as little pressure as possible:
Junction J1 = jugular-subclavian (linear and / or microconvex)
J2 = at thyroid lobe
J3 = just above the carotid bifurcation
Vertebral veins: longitudinal scan in V2 Intracranial veins:
Transtemporal window: piano midbrain and basal vein of Rosenthal
Condylar window: petrosal sinus top, bottom, homo and contralateral
The study should be started in the supine position (in which prevails the outflow jugular) for viewing and evaluation, in order, of the jugular and vertebral right, the left jugular and vertebral, and intracranial veins. It then goes to a sitting position (in which prevails the spinal outflow) to re-evaluate after a settlement of 1-2 minutes) the jugular veins and vertebral.
The parameters to be measured are given in Table 2.
Table 2 - Parameters to be measured for the diagnosis of CCSVI ECD
- presence / absence of flow (jugular and vertebral supine and sitting)
- flow direction longitudinal color / PV (jugular and vertebral supine and sitting)
- flow direction intracranial veins (for the window condylar with dedicated software)
- Cross-sectional area of the jugular veins in J2 (supine and sitting)
- B-mode abnormalities of the lumen, wall or tube of the jugular veins (J1)
- Presence of reflux> 0.8 "- 1.0", and / or venous flow bidirectional
Particular attention should be paid to the choice of probes and its setting. The linear probe 7.5 - 12 MHz is to be used for the study of the jugular veins in J2 and J3 and vertebral V2. The jugular J1 should be studied with probe microconvex from 5 to 8 MHz for the jugular in J1. For the study of intracranial it is advisable to probe Cardiology 1-4 MHz
The diagnostic criteria for the diagnosis of CCSVI are the five initially described by Zamboni, but are divided into four major criteria (extracranial) and a secondary criterion (table 3). The diagnosis is satisfied if there are three major criteria (1, 3, 4, 5); if there are at least two major criteria (1, 3, 4, 5) more than the criterion accessory (2).
The study intracranial, which involves the use of dedicated software, can be omitted diagnostic of routes. The failure does not affect the diagnosis if there are three of the four major criteria, but may result in false positives if there are only two criteria.
It is possible to stop the flow in the veins intrarachidee (normally not visible), the evidence of collateral circulation thyroid and an increase in the flow velocity of> 70 cm / sec, indicative of stenosis.
Table 3 - Diagnostic criteria of CCSVI Criterion 1 to: Bi-directional flow in one or both jugular veins in a lying position and in the sitting position or in a bi-directional flow position and the absence of flow in the other (situation suggestive of stenosis jugular)
b: reverse flow or bidirectional in one or both of the vertebral veins in a lying positionand in a sitting position (situation suggestive of stenosis of vein azygos); evidence of flow in the veins intrarachidee (normally not visible); presence of collateral circulation thyroid
Criterion 3 to severe reduction of the jugular vein in the supine position (
b: the presence of anatomical anomalies, malformations valve / fixation of the valve leaflets, conditioning hemodynamic alterations, presence of septa
Criterion 4 to blocked flow in the jugular veins or vertebral supine position and in a sitting position after forced inspiration or alternatively
b: block in a posture and two-way flow in the second (suggestive of steno-occlusion distal)
Criterion 5 abnormalities in the jugular with non-
reduction in cross-sectional area of the vein to
changing position from lying to sitting
presence of reflux in the intracranial veins inspiratory
The Rapporteur also reminded the Venous Insufficiency Hemodinamic Severity Score (VHISS), useful in the follow-up of patients. The scale is from 0 to 16.
For the criterion n ° 1 is assigned a point for each segment (J1, J2, J3 and VV) that provides two-way flow or reflux in both positions to give a minimum value of 0 and a maximum of 8. For the criterion 3 from 0 to 2 points for the presence of stenosis or anomalies in the jugular. For the criterion 4 from 0 to 8 in the presence of level locks jugular or vertebral (J1; J2 J3 and VV). For the criterion 5 0 to 4 in the presence of alterations of the areas jugular.For the criterion 2 from 0 to 2 in the presence of reflux only in a posture or both.
This was followed with over three hours of practical training led by qualified tutors (M. Maiuri, G. Cacciaguerra, E. Menegatti, D.Tonello) during which time the students were able to deepen the approach to patients with CCSVI.
The interactive discussion that concluded the refresher course, stressed that the training of the diagnostician is the crux of the recognition of CCSVI and where even today, in all published studies, the frequency of the diagnosis made in different laboratories varies between zero and fifty percent is a sign that the training of operators is less than good. This is not surprising. Over thirty-five years ago the same thing happened for the evaluation of carotid stenosis. For CCSVI, also, other two elements increases the complexity of the diagnosis. The U.S. examination of the venous system is, in all districts, more difficult than the blood, where the high pressure gradient makes it easy compared to a low-pressure system and high capacitance. The second difficulty is related to the still inadequate knowledge on the pathophysiology of cerebral venous return and its regulation.
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