high-resolution CT scan vs. MRI

[teffaz]

Dear friends,
A couple of weeks ago I was at the hospital, ready to enter the tube of gloom--my one-year post-op MRI to check for any regrowth of my acoustic neuroma. The tech at the hospital informed me that they would not perform the MRI due to some embolization coils in my abdomen from a previous surgery which are not MRI compatible. Therefore, my neurotologist scheduled a high resolution CT scan in lieu of the MRI.

I'm a bit concerned that the CT scan will not be able to do the job.

Just wondered if anyone else was unable to have an MRI because of metal in their body, and if so, did you have a high resolution CT scan instead?

Best,
Brenda

[ppearl214]

Hi Brenda.

From personal experience this week (over 4 yrs post radiation for my AN)....

I had to have a head CT without contrast for a non-AN related issue.  Dr came in, told me all was fine (for original suspicious issue) and noted to me that they saw my dead AN clearly (even without constrast).   Only concern I have is lifetime radiation exposure due to CT issues (well publicized) vs. non-radiation of MRI's. If there is metal in your body that rules out an MRI,  a CT scan should help show if anything is there.....

Hope that helps.
Phyl

[rupert]

Hi Brenda,

            Just curious,  what scan did they use to diagnose your AN at first?

                                                                                             Bryan

[teffaz]

Phyl: Thank you for your reassuring post!

            Just curious,  what scan did they use to diagnose your AN at first?

                                                                                             Bryan

That is a good question!  I had surgery three years ago for severe varicosities, and had stainless steel embolization coils implanted in my iliac vein. The interventional radiologist who performed the surgery told me the coils were MRI compatible. The facility near my home that performed the MRI at the beginning of 2009 must have relied on the note from that doctor that the coils were MRI compatible. That MRI showed my acoustic neuroma. A few months later, the day before my translab surgery at a different facility, my neurosurgeeon ordered another MRI. That facility refused to perform the MRI, stating that the coils were not MRI compatible.

For my one-year post-op MRI, I returned to the facility near my home. This time, the tech refused to perform the MRI. One might ask, why did they refuse this time, when they didn't the first time? I don't know; I dealt with the same tech both times.

If you want my opinion, I think I was just very fortunate to have had the first MRI! Maybe it was just meant to be!

Best,
Brenda

[CHD63]

Brenda .....

I had a similar experience.  My first brain surgery (in 1994) included leaving "teflon pads" supporting an artery off the trigeminal nerve at the brain stem.  I was told they would not interfere with subsequent MRIs or airport screenings.  When I began having pronounced balance issues 13 years later, the MRI facility at first refused to do a scan.  It was not until my operative report was faxed to them and reassurance from my doctor that they agreed to do it.

It seems to me it is a matter of who is most afraid of being sued .....  Although, stainless steel does sound like it would be incompatible.  Truthfully, the protocol for MRI scanners may have changed since your first post coils scan.  Bummer!

My neurosurgeon also said CT scans should pick up at least the shadow of an AN.  It is just that an MRI with contrast gives the most definitive view.

Best thoughts.  Clarice

[teffaz]

Thanks, Clarice.

I just got word from my neurotologist that my HRCT scan showed no tumor.

I'm thankful!

Brenda

[CHD63]

Brenda ....

Yeah, that's what we like to hear!

Clarice

[Tumbleweed]

What I was told by Dr. Chang (Stanford doc) is that CT scans are actually more accurate than MRIs but harder to interpret by the eye. So doctors like to see an MRI to make a diagnosis, but a CT scan is used in preparing the radiation treatment plan because of its superior accuracy. MRIs are usually used in lieu of CT scans for post-treatment followup views to avoid the high dose of radiation that CT scans unfortunately deliver to the patient.

Best wishes,
TW