ANA Discussion Forum
Pre-Treatment Options => Pre-Treatment Options => Topic started by: ANSydney on April 21, 2017, 12:39:24 am
There have been a lot of question about doing an MRI without gadolinium contrast agent. The reason for this is, although it is chelated, gadolinium is a heavy metal and particularly those having ongoing MRI scans, it is a concern.
The answer is a high-resolution T2-weighted MRI is comparably accurate and economical alternative to the gold standard of contrast-enhanced T1-weighted MRI. So, avoiding an unfavorable substance and cheaper! The article recent from 11 April 2017:
Keep in mind that this would not apply to your initial MRI, which needs to be able to identify any tumors. Once you know where it is, a high-resolution T2-weighted MRI will be able to examine growth. It's what I'll be using for for next MRI.
Good to know! Thanks for sharing!
A very recent article, for those that are interested entitled "Gadolinium-Based Contrast Agents and Brain Safety: Signal vs Noise" from Medscape dated July 26 2017, http://www.medscape.com/viewarticle/881864
Oh no. I still have 3 more to go before they cut me loose. Something else to worry about. :(
If all your looking for is size change, a T2 weighted MRI will do the trick without the gadolinium contrast agent. T2 weighted with fast spin echo (fse) or turbo spin echo (tse) looks the best.
USC Keck and Brigham and Women's are getting the 7.0 T MRI that it super powerful.
I wonder if they still need to use the contrast dye for that. I would like an alternative because I don't believe in yearly scans with contrast. It's possible that one might need decades worth of scans, in which case that's a lot of dye. I know someone who just had a kidney transplant so it's concerning to me.
My next scan to determine tumor size change will be done without gadolinium contrast agent. So, I've had two with gadolinium contrast agent, but from now on it will be without. I've requested T2 weighted images and hopefully the MRI place knows that fast spin echo (fse) or turbo spin echo (tse) is the best subtype under T2 weighted images.
My summary is to get your diagnostic MRI done with contrast agent (T1 weighted and T2 weighted), but switch to a T2 weighted image from then on. I'll let you know how successful this approach is once I've had my next (T2 weighted) MRI at the end of the month. Also the tumors growth profile.
By the way, don't get T1 weighted and T2 weighted confused (which define the MRI pulse sequence employed) with the power of the MRI machine T1.5, T3, etc (which is the magnetic power of the machine in Teslas). I just realized that this will probably confuse many.
Most people will use a 1.5 T machine. The image quality coming from a 3.0 T machine is much better. I can only imagine how wonderful a 7.0 image would look (and how expensive). I find 1.5T to give enough resolution to keep track of size.
It seems that this subject is getting some attention in the Medical Scientific Community...
I am sure that many of us in W&W are likely to have more than one MRI and perhaps many more. I do plan on discussing this with my Neurotologist soon when we meet to decide on the timing and parameters of my next MRI.
As requested by the Neuroradiologist that read my first MRI, I am scheduled for a Temporal Bone/Skull Base CT Scan next week for further evaluation. I recall that my Doctor expressed his concern about the CT scan saying that it is not something to be done unless absolutely necessary due to the radiation exposure.
Thanks for posting the article. I believe a T2 weighted MRI can be used after the diagnosis MRI to determine growth. I've got my next MRI scheduled for August 26 without gadolinium contrast agent and I'll let you know if I can still determine size, once I've had the MRI.
I'm not a fan of CT. Do you think your doctors can ascertain what they would like to know without a CT scan?
Thanks for the article.
It's difficult for an AN patient to avoid MRIs with contrast. I guess it just goes with the territory.
My next MRI will be my seventh for this condition. When patients are diagnosed early there will be lots of MRIs. I suppose patients that are diagnosed with a larger tumor and are treated surgically soon thereafter will receive fewer MRIs. I think they spread them out and phase them out.
Patients who elect for radiation are probably looking at an entire lifetime of monitoring. Depending on one's age that can be a long time. One also has to account for how many MRIs and CT scans already received for other conditions. This can be a lot depending on the person.
When you are first diagnosed it's difficult to see that far down the road. After more than three years and slow growth (if at all) it's difficult to say how best to proceed.
Keep on scanning I guess.
My first two MRIs were done with gadolinium contrast agent. My next one, on August 26, will be done without. I'll let you know if it is suitable (should be).
From my understanding, a T1 weighted MRI with contrast is good for diagnosis. Followup MRIs can be done with a T2 weighted MRI and no contrast. If all you want to check is dimensional changes, this should be enough. Post radiotherapy, you also want to look at tumor characteristics and I don't know the best approach.
Great post. I too have been reading about the growing concern with the use of this contrast agent. So far I have been getting the standard answer that it is a medically safe and recommended tool from Physicians and imaging centers. I am at the 2-year post-op point and just had what I believe will be my last MRI using a contrast agent. From this point on I've decided to reject use of the contrast in my further scans.
Very helpful to read in this thread about the different scanner resolutions. I'll seek better scanners without contrast agent going forward.
Many thanks, Karl
T1 weighted and T2 weighted are not different scanners, but different settings within the same scanner. If you want to know more, take a look at http://casemed.case.edu/clerkships/neurology/Web%20Neurorad/MRI%20Basics.htm
One of the key reasons that gadolinium based contrast (GBC) agents can no longer be considered safe is related to kidney disease. The European Medical Authority suspended the use of Magnevist, Omniscan and Optimark. Multihance has been restricted to liver scans. GBC agents are also known to show up in the brain and other sensitive issues. Sure, the image readers like the benefits since they 'pop' the lesion(s), yet at what price to the patient? Some agents such as gadobenate dimeglumine may carry lower risks. Trod carefully as your AN continues to be monitored with MRIs that need enhancements.
My last MRI was done without gadolinium contrast agent. Future ones will also be done without. Certain weighted MRI give enough detail for measurement.
My algorithm is to have the first MRI with gadolinium agent and then to have subsequent ones without. This assumes you don't have kidney problems.
My initial MRI without contrast was done with the following sequences: 1 Sagittal T1; 2 Axial T2 Flair, diffusion, 3. Coronal T2 and the findings were suspicious for a mass with recommendation for follow up with contrast induced images. A week later, the MRI with/without contrast was done, which found a 1.4 cm acoustic schwannoma with the sequences: 1 Axial T1, Flair. Thin section axial space and T1 of the bilateral internal auditory canals and thin section post contrast axial and coronal of the bilateral internal auditory canals with fat saturation. Post contrast axial T2 of the entire brain. The first line in the comment refers to minimal increase in T2 signal abnormality.
I have no idea what these sequences mean. Even though T2 is mentioned in the report, should I assume this was done with T1. Would a prescription for a follow up study need to specify without contrast and using T2? What are my options if the MRI center and/or the ordering doctor tell me I must have contrast? Should I show him the PubMed abstract?
My first appointment with the neuro-otologist (at Jefferson, Philadelphia) is this week.