Warning: include(/data/htdocs/hebergementweb/sites/imagemed.univ-rennes1.fr/en/nav.html): failed to open stream: No such file or directory in /data/htdocs/hebergementweb/sites/imagemed.univ-rennes1.fr/template.php on line 144

Warning: include(): Failed opening '/data/htdocs/hebergementweb/sites/imagemed.univ-rennes1.fr/en/nav.html' for inclusion (include_path='.:/usr/share/pear:/data/htdocs/hebergementweb/php-include') in /data/htdocs/hebergementweb/sites/imagemed.univ-rennes1.fr/template.php on line 144

Site map

Iron and fat
- Hepatosiderosis
- Steatosis
- Quantification methods
- On-line iron quantification xxx
- MRQuantif
  - Overview
  - MRI protocols
  - Download
  - User guide
  - PACS integration
  - Validation
OxyMonitor
- Download

On-line liver iron anf fat quantification using MRI data

On-line DICOM tool to quantify iron and fat in the liver using a single MRI multiechoes sequence. No installation required. Browse, view and analyse directly from your disk.

To access this page you must be registered with a valid e-mail. Click on "Log on" and select "Register".

To have better results and avoid major errors you should now :

aquire a single multiecho sequence (or merge several monoecho sequence if you have a GE system without starmap)

read and process your images with the freely downloadable "MRQuantif" software or with this on-line tool.
If you have a specific reason to continue to use the previous form contact me.

{{countDown}} left

You should not use this page anymore! You only have a few days left to implement the new algorithm that calculates R2 * and SIR with a single sequence. The result is more precise and more reproducible.

Use now a unique gradient echo sequence with 8-10 echos with this acquisition protocol.
Download, integrate and use our MRQuantif software to get a joint liver iron and fat concentration at 1.5T or 3T.

*MR field used:*
*MRI brand used:*
*Coil selected:*	automatic coil selection inactivated

No magnetic field selected.

It is not possible to compare liver and muscle with this coil selection.

Type in the mean values of MR signal given by ROIs, up to three for the liver and one or two for the paraspinal muscles. Do not put decimal values, measure is not so precise ! If you have acquired the old protocol enter only the data for the 3 unchanged sequences (in bold) +++ Adapt your acquisition protocol, preferably by using a single multiecho sequence.
The first sequence has now a shorter TE to be able to quantify high overload. It is useful only if the second sequence, existing in the old protocol, shows a complete liver signal decrease. The last sequence is not mandatory, but if you use it please switch to a 19ms TE instead 21ms to better be in-phase.

Patient:

TR / TE / PA°	Liver(1)	Liver (2)	Liver (3)	Muscle (1)	Muscle (2)	L/M	LIC	Comments
Out (1): GRE 120 / {{te[0]}} / 20°	Out (1): GRE 120 / {{te[0]}} / 20°						{{LMs[0]}}	{{CHFs[0]}}
Out (1): GRE 120 / {{te[0]}} / 20°	drag and drop a DICOM image of this serie in the drop zone
*In (1): GRE 120 / {{te[1]}} / 20°*						{{LMs[1]}}	{{CHFs[1]}}
In (1): GRE 120 / {{te[1]}} / 20°	drag and drop a DICOM image of this serie in the drop zone
*In (2): GRE 120 / {{te[2]}} / 20°*						{{LMs[2]}}	{{CHFs[2]}}
In (2): GRE 120 / {{te[2]}} / 20°	drag and drop a DICOM image of this serie in the drop zone
*In (3): GRE 120 / {{te[3]}} / 20°*						{{LMs[3]}}	{{CHFs[3]}}
In (3): GRE 120 / {{te[3]}} / 20°	drag and drop a DICOM image of this serie in the drop zone
In (4): GRE 120 / {{te[4]}} / 20°	*In (4): GRE 120 / {{te[4]}} / 20°*						{{LMs[4]}}	{{CHFs[4]}}
In (4): GRE 120 / {{te[4]}} / 20°	drag and drop a DICOM image of this serie in the drop zone
*In (5): GRE 120 / {{te[5]}} / 20°*						{{LMs[5]}}	{{CHFs[5]}}
In (5): GRE 120 / {{te[5]}} / 20°	drag and drop a DICOM image of this serie in the drop zone
*In (6): GRE 120 / {{te[6]}} / 20°*						{{LMs[6]}}	{{CHFs[6]}}
In (6): GRE 120 / {{te[6]}} / 20°	drag and drop a DICOM image of this serie in the drop zone

Results :

Infos

This algorithm calculates the liver iron concentration (LIC) from each MR sequence, then tries to select the most appropriate result, around 0.5. Check the different values to validate the automatic selection according to these rules:

In case of slight overload, the accuracy is better with the most sensitive MRI sequences with long TE. The sequences that gives a signal above the background noise are therefore selected to give the result whereas the less sensitive MRI sequences with short TEs overestimate the overload.
In case of moderate overload, sensitive sequences with long TE have a collapsed signal and underestimate the concentration. The less sensitive sequences with short TE are then more accurate,
In case of a major overload, the less in-phase sensitive sequence can also have a collapsed signal and the quantification requires the use of the sequence in opposed-phase with the shortest TE.
In the case of hepatic steatosis, the shortest TE opposed-phase sequence erroneously gives a high iron concentration. Normally, the algorithm recognizes this condition since the signal is lower than on the subsequent phase echo.

AT 1.5T this algorithm overestimates slight and moderate liver iron overload. We recommand you to switch to the new acquisition protocol based on a unique multiecho GRE and to use the MRQuantif software which calculates jointly LIC (by T2* and SIR method) and fat fraction.

Version of January 21th, 2018. If not working properly contact me (yves.gandon@univ-rennes1.fr).

updated: April 23 2021 09:39