Reviewer's report
Title:The role of MR imaging in detection of hepatic iron overload in patients
with cirrhosis of different origins.
Version: 1Date:12 August 2009
Reviewer: Paul E Sijens
Reviewer's report:
The topic is interesting and the size of the study is good (44 patients with liver
cirrhosis of whom 20 with elevated iron concentration according to non-MRI
methods used as gold standard).
Major Compulsory Revisions:
My problem with the design of this study is that the results of MRI and the
alternative methods are presented in a semi-quantitative manner. Why didn’t the
authors use a method such as that of Gandon et al. (refs 10,11) to come up with
the liver iron concentrations or T2* values according to MRI to be compared with
the liver iron concentrations or other quantitative measures, such as the blood
ferritin concentrations, determined by the reference methods?
As correctly stated in “background” the efficacy of some of the reference
methods suffers from relatively low sample representativity in patients with liver
cirrhosis. So how good are they as gold standard, anyway?
The selection of liver volumes of interest is problematic. In Fig.1 a large central
liver area is used, but in Fig.2 and three other areas appearing to be selected as
dark as possible. This all looks extremely biased to me. To add to the confusion,
in the M&M description the authors speak of “randomly” selecting very small
VOIs away from big blood vessels. I would have preferred the analysis of a large
liver area, standardized to approximate the volume depicted in Fig.1.
To obtain a potentially publishable study, all MRI data should be reanalyzed and
be compared with the most quantitative amongst the alternative methods used,
preferably not the Scheuer’s grading scale. In order to assess whether of not
cirrhosis makes small-liver-sample methods less representative, it would be
necessary to include patients without cirrhosis in the study. Elsewhere it has
been shown that in a subgroup of patients without inflammation the correlation of
ferritin with MRI-Iron content was better than in all patients combined (Olthof et
al. MRI 2007;25:228). In analogy to that, I would expect that here the
histology-MRI correlation would be worse for cirrhotic patients than for
non-cirrhotic patients.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests
Reviewer's report
Title:The role of MR imaging in detection of hepatic iron overload in patients
with cirrhosis of different origins.
Version: 1Date:12 August 2009
Reviewer: Paul E Sijens
Reviewer's report:
The topic is interesting and the size of the study is good (44 patients with liver
cirrhosis of whom 20 with elevated iron concentration according to non-MRI
methods used as gold standard).
Major Compulsory Revisions:
My problem with the design of this study is that the results of MRI and the
alternative methods are presented in a semi-quantitative manner. Why didn’t the
authors use a method such as that of Gandon et al. (refs 10,11) to come up with
the liver iron concentrations or T2* values according to MRI to be compared with
the liver iron concentrations or other quantitative measures, such as the blood
ferritin concentrations, determined by the reference methods?
As correctly stated in “background” the efficacy of some of the reference
methods suffers from relatively low sample representativity in patients with liver
cirrhosis. So how good are they as gold standard, anyway?
The selection of liver volumes of interest is problematic. In Fig.1 a large central
liver area is used, but in Fig.2 and three other areas appearing to be selected as
dark as possible. This all looks extremely biased to me. To add to the confusion,
in the M&M description the authors speak of “randomly” selecting very small
VOIs away from big blood vessels. I would have preferred the analysis of a large
liver area, standardized to approximate the volume depicted in Fig.1.
To obtain a potentially publishable study, all MRI data should be reanalyzed and
be compared with the most quantitative amongst the alternative methods used,
preferably not the Scheuer’s grading scale. In order to assess whether of not
cirrhosis makes small-liver-sample methods less representative, it would be
necessary to include patients without cirrhosis in the study. Elsewhere it has
been shown that in a subgroup of patients without inflammation the correlation of
ferritin with MRI-Iron content was better than in all patients combined (Olthof et
al. MRI 2007;25:228). In analogy to that, I would expect that here the
histology-MRI correlation would be worse for cirrhotic patients than for
non-cirrhotic patients.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests
Please review this paper.
user
Reviewer's report
Title:The role of MR imaging in detection of hepatic iron overload in patients
with cirrhosis of different origins.
Version: 1Date:12 August 2009
Reviewer: Paul E Sijens
Reviewer's report:
The topic is interesting and the size of the study is good (44 patients with liver
cirrhosis of whom 20 with elevated iron concentration according to non-MRI
methods used as gold standard).
Major Compulsory Revisions:
My problem with the design of this study is that the results of MRI and the
alternative methods are presented in a semi-quantitative manner. Why didn’t the
authors use a method such as that of Gandon et al. (refs 10,11) to come up with
the liver iron concentrations or T2* values according to MRI to be compared with
the liver iron concentrations or other quantitative measures, such as the blood
ferritin concentrations, determined by the reference methods?
As correctly stated in “background” the efficacy of some of the reference
methods suffers from relatively low sample representativity in patients with liver
cirrhosis. So how good are they as gold standard, anyway?
The selection of liver volumes of interest is problematic. In Fig.1 a large central
liver area is used, but in Fig.2 and three other areas appearing to be selected as
dark as possible. This all looks extremely biased to me. To add to the confusion,
in the M&M description the authors speak of “randomly” selecting very small
VOIs away from big blood vessels. I would have preferred the analysis of a large
liver area, standardized to approximate the volume depicted in Fig.1.
To obtain a potentially publishable study, all MRI data should be reanalyzed and
be compared with the most quantitative amongst the alternative methods used,
preferably not the Scheuer’s grading scale. In order to assess whether of not
cirrhosis makes small-liver-sample methods less representative, it would be
necessary to include patients without cirrhosis in the study. Elsewhere it has
been shown that in a subgroup of patients without inflammation the correlation of
ferritin with MRI-Iron content was better than in all patients combined (Olthof et
al. MRI 2007;25:228). In analogy to that, I would expect that here the
histology-MRI correlation would be worse for cirrhotic patients than for
non-cirrhotic patients.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests
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