CT Scan?

[Karl28]

I want to get a scan of my head but I'm too afraid to get a MRI scan because of how loud and long it is.
However I've read that a CT scan is pretty quiet?

So would it be worth doing a CT scan for tinnitus instead of a MRI?

What's the difference?

 

[attheedgeofscience]

So would it be worth doing a CT scan for tinnitus instead of a MRI?

That would depend in part on what you are trying to etablish via the CT or MRI examination. I would always choose an MRI over a CT scan when examining the head for reason #2, below.

What's the difference?

1. Image quality (Generally better for MRI, but there are exceptions eg. examination of the airways)
2. Radiation (x 200-300 of a normal x-ray for CT scan; none for MRI)
3. Dye (worse side-effects for CT scan)
4. Examination time...

 

[Jay M]

That would depend in part on what you are trying to etablish via the CT or MRI examination. I would always choose an MRI over a CT scan when examining the head for reason #2, below.



1. Image quality (Generally better for MRI, but there are exceptions eg. examination of the airways)
2. Radiation (x 200-300 of a normal x-ray for CT scan; none for MRI)
3. Dye (worse side-effects for CT scan)
4. Examination time...

Side effects for dye? Please explain. Thx

 

[Dr. Nagler]

@Karl28, here's how I see at it - MRI v CT for tinnitus.

The question is ... what are you looking for? In the setting of tinnitus, to me the only reason to do either scan would be to identify a lesion of significance that cannot be identified on physical examination or audiological evaluation. And the only lesion of significance that falls under that umbrella would be an acoustic neuroma (also called a vestibular schwannoma), which is a relatively rare benign tumor involving the VIIIth nerve. Certainly there are other lesions associated with tinnitus that can be seen on CT or MRI (otosclerosis, leptomeningeal carcinomatosis, etc.), but by the time these lesions present with tinnitus, they will likely already be apparent due to other symptomatology or audiological findings. (By the way, about the leptomeningeal thingie - it's extremely rare ... and if you have it, you'll be very ill way before the onset of tinnitus!)

So, back to CT v MRI - does everybody with tinnitus need one ... and if so, which one? Well, since we are looking for an acoustic neuroma, which is almost always unilateral and even if bilateral is not symmetrical, I would say that a scan would be indicated for individuals presenting with unexplained asymmetrical tinnitus lasting more than six weeks. An example of explained asymmetrical tinnitus would be tinnitus in the left ear of a right-handed hunter presenting after shooting a rifle or shotgun for an afternoon of hunting. (The right ear is relatively protected by the right shoulder.) So as I see it, in unexplained asymmetrical tinnitus (with or without asymmetrical hearing loss), a scan is indicated.

Which scan? Well, for large acoustic neuromas, they are probably equally good. But for small acoustic neuromas, the MRI is superior. Moreover, the use of contrast (gadolinium in the case of an MRI) significantly adds to the sensitivity of the study - and if you are going to go to the trouble of having the study, you want the yield to be as great as possible ... otherwise why bother? So unless there is a strong medical contraindication to using gadolinium contrast, the test that should be ordered is "MRI of the Brain and Internal Auditory Canals with and without Gadolinium to Rule Out Acoustic Neuroma." (I always add in "to rule out acoustic neuroma" so that the neuroradiologist interpreting the study has every advantage possible.)

Hope this helps more than confuses.

Dr. Stephen Nagler

 

[Thegeen]

@Dr. Nagler - I have asymmetrical tinnitus lasting 6 years. It is constant, louder at times than others. Sounds like "eeeeeeeeeeeeeeeeee" but very high pitched. Are there other, more common, reasons for asymmetrical tinnitus or is Acoustic Neuroma most likely the cause? I have an appointment tomorrow with ENT and will request "MRI of the Brain and Internal Auditory Canals with and without Gadolinium to Rule Out Acoustic Neuroma." Thank you!

 

[Dr. Nagler]

@Thegeen, it is not at all likely that you have an acoustic neuroma. As I mentioned in my post, these lesions are rare.

Dr. Stephen Nagler

 

[Karl28]

I would like to get a scan of my brain to rule out anything that could be causing my tinnitus and eustachian tube dysfunction but theres no way I would ever get in one of those noisy machines even with earplugs and ear muffs on. No way nothing could convince me.

Are there any alternatives? Other types of similar scans but not as noisy?

 

[Matt01]

I had one and it wasn't that noisy. Had ear plugs and then further sound dampener over that. Reduced noise hugely.

 

[Codaz]

CT Scan is not noisy. It only turns around you and does some beeps. < 4 mins you are done. I had one done a couple of months ago to inspect my constant running nose.

MRI makes a hell of a lot more noise. So that's why I didnt do it. But, there are alternatives like the big or wide bore MRI (for heavy people) that is newer and makes less noise. Or, if you can GE has an almost silent MRI. Unfortunately only present yet in some hospitals around the world.

Furthermore some people here on the forums went into the MRI with earplugs and earmuffs and said it was fine, others said it was terryfing. From what I know the sound is not continuous but episodic.

 

[linearb]

Yes, as others have mentioned, a CT scan was no big deal with no noise at all, and an MRI was totally fine with plugs in.

Neither showed anything useful in my case.

 

[Asian]

CT scan isn't noisy at all. If you meant MRI scan, wear ear plugs and noise canceling headphones upon that. You should be OK

 

[Karl28]

Oh I think I made a mistake and meant loud MRI scan.

Is a CT scan a good enough alternative then?

 

[Codaz]

Oh I think I made a mistake and meant loud MRI scan.

Is a CT scan a good enough alternative then?

Did you Google this? What did the doctor say?

To my understanding a CT only shows bone and some skin. Not nerves, veins or tumors.
MRI is much different.

 

[Matt01]

If you need an MRI, you should get one. Just double up ear protection. It was absolutely fine for me.