Tumor size from CD

[shygirl]

Hi all-

I was looking at the mri CD and found a different view. Well, I measured it on the "new" view and it measured 2.1 cm. The Drs told me it was 1.8 cm.  Now I find this new measurement and I'm kinda freaked by it.

Has anyone else had a Dr mismeasure the size?

[Tumbleweed]

Yes, but usually only by 1 mm. My doctors at Stanford came up with the same measurements as me, but the lab where both my MRIs were done cited some measurements that were 1 mm smaller or larger in both MRIs.

Be sure that you're only measuring that portion which is truly white. At the lateral extent of the IAC, the IAC may appear gray and you might mistake that to be part of the tumor. That can mistakenly add 1 or 2 mm to your measurement.

Best wishes,
Tumbleweed

[shygirl]

Tumbleweed-

It was just the bright white "blob". I first looked at it from the side view and it measured 1.8. When I found the view from the top of my head, that's when it got bigger. I assume the Drs didn't measure the "tail" which was extending from the IAC. It looks that way, at least.

Thanks for your reply.

[mk]

My initial MRI report stated that the "largest" dimension was 2.4 cm. The one 6 months afterwards, was more like 2.9 cm. Of course I totally freaked out, because I thought this was some kind of wacky growth. Then I went back and checked the original MRI scans on the CD myself. The 2.4 cm referred to the coronal (vertical dimension), whereas the axial dimension was more like 2.7 cm, according to my measurements. And the number of slices was much less, which means that it could have been even larger. To make things worse, some of the doctors I consulted afterwards counted the portion in the IAC in, and this gave a measurement of 3.5 cm  . I have no idea to this day how the radiologist came up with the 2.4 cm measurement, but I am still upset about it.

Marianna

[Tumbleweed]

Marianna, I've seen a few inconsistencies in my MRI reports, even though I've only had two! The first one said the medial extent of my then 1.8cm (I measured 1.9) tumor was 2 mm from the fundus of my IAC -- which is anatomically impossible. When I pointed out they must've meant to write lateral extent, they said they'd fix that sentence in the followup report.

Best,
Tumbleweed

[Jim Scott]

FWIW:  I just let my neurosurgeon do the measuring.  He is very well aware of all the variables involved in MRI scans and can analyze the AN and determine it's actual size much better than I ever could.  Besides, that what he gets paid to do.  But that's just me. 

Jim

[Nancy Drew]

I do understand that the measurements can be off a bit here and there.  If the typical growth is 1-2mm a year, then how can the doctors be sure the AN has grown if the measurements can possibly be off by one mm.  I have had four MRIs with contrast at the same place done by the same person.  Three have shown no growth.  However, the second one showed a measurement that was 2mm different from the first one.  My doctor didn't think the AN had grown so he had another doc measure it, and that doc sided with my doc about no growth.  This last MRI showed a slight amount of growth that I guess you could say is so small that it could be a measurement question.  However, if you put all of the MRIs side by side you can definitely see by eye that the AN has a different shape.  Can an AN stay basically the same size for the most part, but at the same time change its shape?  In my case it went from about a 3/4 moon shape to a round moon.  It is so obvious.  I tend to think it really has grown and 8 doctors think so, too. 

Nancy

[shygirl]

Thanks everyone. I really appreciate the input.

I knew the measurement could be off, but I didn't expect 3 mm. I talked to my ENT today and he said they just measured the largest part. Not the length. Okay. He said it was probably longer than 2.1 cm due to the part inside the IAC that was unseen. I guess the fact that it went from a small size to medium just got me wondering. It's gone, so I won't worry about it now.

[leapyrtwins]

FWIW:  I just let my neurosurgeon do the measuring.  He is very well aware of all the variables involved in MRI scans and can analyze the AN and determine it's actual size much better than I ever could.  Besides, that what he gets paid to do.  But that's just me. 

I'm with you Jim.  I leave measurements up to my neurotologist and the radiologist who reads the MRI.

My degree is in business; not medicine, so I figure they understand this stuff much better than I do.

Jan

[Tumbleweed]

At Stanford, they measured my AN in tenths of a mm. I trust their measurements more than those that the imaging center did.

Tumbleweed

[Nancy Drew]

Just a side note off the subject.  Some of you have done so much research that you should be given an honorary medical degree.  This stuff is just way over my head.

Nancy

[leapyrtwins]

Just a side note off the subject.  Some of you have done so much research that you should be given an honorary medical degree.  This stuff is just way over my head.

So, true, Nancy.  I especially love to read posts by Mark.  Where he learned everything he learned, I'll never know, but it truly fascinates me 

Jan

[shygirl]

The neurosurgeon never told me the measurements, the neurotologist did(and I had to ask him). No radiology report--I was simply curious is all.

[Rivergirl]

Nancy Drew's quote about honorary degree so funny, I do feel like I am taking a course. It makes me wonder about a couple things......seeing size matters here, does the shape? and I wonder if different places where you have MRI's can vary with their technique so there can be variations?

[Tumbleweed]

Rivergirl, the shape does matter in so far as it determines the volume of the tumor -- which is really more important than the dimension along any one of the three axes of measurement. A spherical tumor has much greater volume than an elliptical one, for example. The larger the tumor volume is, the more important structures it presses against and the more difficult it is to treat without causing collateral damage. At least this is my understanding. Dr. Chang recently told me that most people place too much emphasis on the single greatest axial measurement and said in so many words that the tumor volume is generally more important.

There can be variations in MRI results depending on where it's taken, but I'm not sure if technique is one of the variables (I would think the specific equipment used would be a factor). All I know is that Stanford (where I was treated) and specifically Dr. Chang told me that they would prefer to perform my followup MRIs instead of me having it done elsewhere. I got the feeling that they felt doing so would either yield more consistent or more accurate results. They were open to me having the MRI performed elsewhere, but had a clear preference to do it in-house.

Best,
Tumbleweed