Variability of Fibroscan Results

[KimInTheForest]

Apologies if this is the wrong forum. Was not sure which stream to post it in.

I just wanted to share my own recent experience with the variability of fibroscan results used for staging liver fibrosis - especially since many people's insurance companies won't authorize treatment (or at least expensive New Drug Tx) until you are Stage 3. Yet depending on which clinic you go to, which Fibroscan technician you get, what size rod they use, what your ALT level is that day, whether you fasted before the test or not, how much they contort you to get the reading, and apparently a host of other factors… your result could vary by one entire F-stage. Which could make the difference between an insurance company authorizing your treatment or not. So at very least, get a 2nd one done somewhere else if a different value would 'help your case'. (In my own case, my F-stage does not affect my access to treatment. But for others it may.)

5 months ago I had my 1st fibroscan done. The reading was 10.4 Kpa, which meant I was Fibrosis Stage 3. The 1st technician was not able to get any reading at all, and had to call a senior technician in to have a go at it. (Apparently my ribs are close together.) The 2nd technician got me into a very contorted position to separate my ribs enough for the rod to tap my liver and not bone, and came up with the reading of 10.4. I had been told to fast for 2 hours prior to the Fibroscan.

Today I had a 2nd Fibroscan done at a different clinic (as part of my screening test for a drug trial I expect to begin in a couple of weeks). So the Fibroscan was done on a different machine and done by a different operator. Today's value was just 8.5 Kpa, which puts me at Fibrosis Stage 2, not 3. I like that number better so have updated my sig file accordingly. Haha!

I had not been instructed to fast prior to today's Fibroscan. This technician used a small-diameter rod for the tapping (to get in between my ribs better), she did not put me into a contorted position (which I think increased my liver pressure substantially the first time), she worked out a system very quickly to tap me between breaths (liver more accessible through ribs at that moment perhaps?).

Also, if your ALT is > 100 at the time of your Fibroscan, that alone can increase your reading by 2.0 Kpa, which can put your diagnosis into a different stage. Here is an article on that: http://www.ncbi.nlm.nih.gov/pubmed/19430093

Wellness to all,
Kim

[BubbaT]

Hi Kim,

Thanks for posting this, I have not heard yet how this procedure is being done.
I'm thinking this is subjective to technician use and training, based on the experience you described...

And a host of other factors, calibration of the scanner, etc..

This leaves a lot of room for speculation on the accuracy of this machine...

IMHO ,

Thanks again..

[KimInTheForest]

It does indeed leave room for speculation about accuracy of these machines and their readings, BubbaT. And the concerning part is that it is often the reading from a fibroscan machine that determines whether or not a person's insurance company will approve them for new drugs for HCV. If you are Stage 3, you're approved, Stage 2 "you aren't sick enough yet" (for some/many coverage plans). Fibroscan is considered quite accurate for measuring fibrosis at Stage 3 or 4. And considered pretty accurate at Stage 2. But really I don't think it is. I think people may want to consider getting a 2nd fibroscan done at a different place if their first one did not give them a result that helped them with their insurance coverage - because of how much variability there can be.

Fibroscan is a specialized ultrasound that measures liver stiffness. It has replaced more intrusive biopsy in many situations where biopsy would have been used in past to stage the liver. A metal rod is used to gently tap on your skin between your ribs, and then some radio-wave acoustic measurement of the speed at which that thump propagates through liver tissue converts into a number in units of Kpa (kilopascals - metric alternative to PSI for tires). It doesn't hurt (unless maybe your liver is really inflammed at time of testing), and nothing goes inside you except sound waves.

The operator must get 10 readings in the same ballpark for their average to be considered an accurate measure of liver stiffness, which correlates to fibrosis as follows:

Less than 7.0 Kpa = F0-F1
Greater than or equal to 7.0 Kpa = F2
Greater than or equal to 9.5 Kpa = F3
Greater than or equal to 12.0 Kpa = F4

My 1st fibroscan, done 5 months ago, was 10.4 (F3).
My 2nd, done yesterday at different clinic, was 8.5 (F2)

Kim

[Lynn K]

If I remember correctly my only fibroscan was 27

Just did it in case insurance wanted a confirmation of my 7 year old F4 liver biopsy

[charly8]

I think you are right Kim, if you are having trouble getting approved based on low fibrosis you should have another test done.

Also you could try the fibrosure test as well.  That is variable and may give you the F3 you need. 

For example, I had the following done:

2011 - Liver Biopsy -  F0 to F1. 
December 2014 - Fibrosure - F3
March 2015 - Fibroscan - 6.8 kpa F0-F1 (was on tx for 1 month)

So if I did the Fibroscan I would not have been approved, but the fibrosure gave me the approval I needed, luckily.

[outfitter01]

Thanks for posting this !  I was told there is variability about the interpretation of the results as well and my insurance is denying treatment although my practicioner diagnosed me as F2.  I will get the test redone!

[dragonslayer]

I think you are right Kim, if you are having trouble getting approved based on low fibrosis you should have another test done.

Also you could try the fibrosure test as well.  That is variable and may give you the F3 you need. 

For example, I had the following done:

2011 - Liver Biopsy -  F0 to F1. 
December 2014 - Fibrosure - F3
March 2015 - Fibroscan - 6.8 kpa F0-F1 (was on tx for 1 month)

So if I did the Fibroscan I would not have been approved, but the fibrosure gave me the approval I needed, luckily.

Good for the coverage; lousy for the reliability of the non-invasive tests!  Folks have to remember that in the general F1-F3 range, these tests are not accurate.

[sabre]

I was wondering about the accuracy of the Fibroscan for lower numbers, too. My biopsy in 2008 registered stage 0, grade 1, minimally active, no fibrosis, mild inflammation. The Fibroscan registered F2 with mild fibrosis.

I'm not saying that I couldn't have progressed to F2 in 7 years, but was just wondering if one was more accurate than the other for those of us who are lucky not to have Cirrhosis.

[Lynn K]

A biopsy is more accurate and considered the gold standard. In the mid ranges is where the fibroscan is less accurate but it is a great way to confirm F4 cirrhosis without the invasive biopsy. So as a fibroscan result F2 all I would be confident in is you don't have cirrhosis it would appear to me anyway.

I had biopsies every 5 years and went from f1 to f2 to f3 to f4 with each subsequent biopsy or over 15 years but as we know many never get to F4 while some get there faster than I did.

So kinda hard to say if you are f1 or more just thankfully you probably do not have cirrhosis

[sabre]

Thank you for the information, Lynn.

[shootingforzero]

I had a Fibroscan done 6 years ago, which showed no fibrosis.

Liver biopsy 3 years ago showed F1-2 fibrosis

Fibrosure and Fibroscan done three months ago showed F1

I'm inclined to believe I've had F1-2 all along.
(Was infected as a newborn and am 35 years old now, so my liver's been inflamed for a while.)