Review for 10.1186/s12876-018-0770-6 (2018)

Reviewer ’s report  
 
Title: 3D high -resolution anorectal manometry i n patients wit h perianal fistulas: comparison 
with 3D-anal ultrasound  
 
Version: 0 Date: 25 Jan 2018  
 
Reviewer: François Mion  
 
Reviewer's report:  
 
The authors must be congratulated for this effort to make the most from 3DARM data in the 
context of perianal fistulas. The results are potentially interesting, but more deta iled informations 
are needed.  
 
 
First of all, to assess the agreement between EUS and ARM, a group of patients with no fistula at 
EUS should be included, and the 3DARM data should be measured blindly from the results of 
EUS: the assymetry or pressure "groove s" as described by the authors are frequently seen in 
patients without fistulas in my own experience.  
 
 
The authors should clearly state if they measured the regional FTA pressures at the position 
identified by EUS, or at the lower regional pressure as seen on the 3DARM open cylinder: this is 
clearly not the same, and the results should be obviously different.  
 
 
Second, the figures and description of methods should be improved. For example, figure 2 is 
supposed to show a good agreement between EUS and ARM: the authors should indicated 
precisely on the figure where is the anterior, posterior left and right on the EUS and ARM. 
Furthermore, the lower pressures on the cylinder seem to be located on the right anterior part of 
the pressure cylinder, while the "groove"  line is situated on the left anterior part of the the open 
cylinder.  
 
 
I also have a problem with the definition of the "pressure groove" and its representation on figure 
2C: the authors indicate in the method that a "groove" was defined  as a delta MRP > 3 0 mmHg 
throughout the entire lenght of the sphincter. However, the dotted line indicating the "groove" 
according to the legend of figure 2c is traced by the software as representative of the lower 
pressure path along the sphincter, whatever the pressures v ariations, and is present in all 3DARM 
recordings.  
 
 
I also encourage the authors to better represent on figures how they measured the upper and 
lower limits of the anterior and posterior high pressure zone on the 2D open cylinder: this would 
be very helpful  for the understanding of the manuscript.  
I don't find figure 4 very uselful, it should be removed, as well as the algorithm presented in 
figure 5: i don't think at this stage that 3DARM can be included in the work -up of perineal 
fistula. The authors thems elves acknowledge in their last sentence that "3DARM ...cannot be 
recommended as a routine procedure in patients undergoing fistula surgery".  
 
 
 
 
Are the methods appropriate and well described?  
If not, please specify what is requir ed in your comments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
No 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please e xplain in your comments to the authors.  
 
No 
 
Are you able to assess any statistics in the manus cript or would you recommend an 
additional statistical review?  
If an additional statistical review is recommended, please speci fy what aspects require further 
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Needs some language corrections before being published  
 
 
 
 
 
 
 
 
 
 
 
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following qu estions:  
 
1. Have you in the past five years received reimbursements, f ees, funding, or salary from an 
organisation that may in any way gain or lose financial ly from the publication of this 
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation t hat may in any way gain or lose 
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents  relating to  the content of the 
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing i nterests in relation to this paper?  
 
If you can answer no to all of the above, write 'I declare that I have  no competing interests' 
below. If your reply is yes to any, please give details below.  
 
'I declare that I have no competing interests'  
 
I agree to the op en peer review policy of the journal. I understan d that my name will be included 
on my report to the authors and, if the manuscript is accepted f or publication, my named report 
including any attachments I upload will be posted on the website along with the  authors' 
responses. I agree for my report to be made available under an Open Access Creative Commons 
CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments 
which I do not wish to be included in my named report can be i ncluded as confidential comments 
to the editor s, which will not be published.  
 
I agree to the open peer review policy of the journal