Tuesday, 6 May 2014

CCSVI & MRI: make sure you are hydrated before your scans

Is dehydration a common cause of brain and spinal cord atrophy? #MSBlog #MSResearch

Is rehydration a simple cure for CCSVI? #MSBlog #MSResearch

"Many years ago whilst I was doing my PhD I found a correlation between urinary creatinine, a breakdown product of muscle tissue, and disability. After some scientific sleuthing I found that it was being driven by urinary concentration that in turn was being driven by dehydration. I found out that MSers with bladder problems were controlling their urinary frequency and urgency by dehydrating themselves. The more disabled you are the more likely you are to have bladder problems, the more likely you are to dehydrate yourself. Some MSers were not drinking any fluids for up to 24 hours before attending hospital. Voluntary dehydration to control bladder symptoms was not a new finding and had been reported in the 1960s"

"It turns out that dehydration also causes brain and spinal cord pseudoatrophy and is probably the cause of CCSVI. I was not surprised to see that the majority of the findings of CCSVI can be cured by rehydration (see abstract below); 1.5 litres of Gatorade cured cured CCSVI in over 70% of cases. Being dehyradted cause the central veins to collapse and hence results in pseudo venous obstruction; simply rehydrating expands the blood volume and the pseudo-obstructions disappear."

"Therefore anyone researching brain atrophy or CCSVI will need to make sure their study subjects are well hydrated before investigating them; this should be part of the standardization procedure."

Epub: Wang et al. Dehydration affects spinal cord cross-sectional area measurement on MRI in healthy subjects. Spinal Cord. 2014 Apr 29. doi: 10.1038/sc.2014.66.

Study design: This was a prospective cohort observational study.

Objective: To determine the effect of dehydration and rehydration on spinal cord cross-sectional area (CSA) measurement on magnetic resonance imaging (MRI).

Setting: MRI Research Centre, University of British Columbia, Canada.

Methods: Ten healthy subjects (aged 21-32 years) were scanned on a 3T MRI scanner at four time points: (1) baseline, (2) rescan after 1 h, (3) the next day after fasting for a minimum of 14 h and (4) after rehydration with 1.5 l of water over the course of 1 h. Two independent, established semi-automatic CSA measurement techniques (one based on two-dimensional (2D) edge detection, the other on three-dimensional (3D) surface fitting) were applied to a 3D T1-weighted scan of each subject at each time point, with the operator blinded to scan order. The percentage change in CSA from baseline to each subsequent time point was calculated. One-tailed paired t-tests were used to assess the significance of the changes from baseline.

Results: A decrease in CSA following dehydration was detected by both measurement methods, with a mean change of -0.654% (s.d.=0.778, P<0.05) and -0.650% (s.d.=1.071, P<0.05) for the first and second methods, respectively.

Conclusion: Dehydration can confound CSA measurements on MRI. The magnitude of the effect is significant relative to short-term pathological changes that have been observed in diseases such as multiple sclerosis.

A simple cure for CCSVI?

Diaconu et al. Hydration status substantially affects chronic cerebrospinal venous insufficiency assessments. Neurol Clin Pract. 2013 Oct;3(5):386-391.

Aims: We sought to determine the effect of hydration on the criteria for chronic cerebrospinal venous insufficiency (CCSVI), a proposed hypothesis for the etiology of multiple sclerosis (MS). 

Methods: Sixteen subjects (11 MS and 5 controls) were asked to fast overnight. The following morning, 2 CCSVIultrasound examinations were performed: 1 in the mildly dehydrated state, and another 30-45 minutes after rehydrating with 1.5 L of 

Results: Gatorade. Seven subjects fulfilled CCSVI criteria in the dehydrated state. Of these, 5 (71%) no longer fulfilled CCSVI criteria after rehydration. One additional subject met CCSVI criteria only after rehydration. 

Conclusion: Hydration status has a substantial effect on CCSVI criteria, suggesting that the sonographic findings of CCSVI may represent a physiologic rather than pathologic state.