Review for 10.1186/s12876-020-01300-4 (2020)

Reviewer’s report
Title: Bilateral vocal cord paralysis after endoscopic placement of fully covered self-expandable metal
stent for palliative treatment of malignant proximal esophageal obstruction: two case reports
Version: 0 Date: 04 Apr 2020
Reviewer: Rizwan Ahamed
Reviewer's report:
After reading the article in detail, what strikes immediately unfortunately, is the poor quality of the
English language used in the manuscript including grammatical errors even in the abstract. Kindly
correct these so that the scientific aspects can be assessed accurately. In addition to this, I have a couple
of queries regarding the study.
1. When it is mentioned that the vocal cords were paralysed in adduction, are the authors trying to say
"paramedian position"? If not, does being in adduction help in localizing the involved nerve to be the
posterior  branch  of  the  recurrent  laryngeal  nerve?  A  little  more  discussion  on  the  applied
Neuroanatomy in the discussion part could make the manuscript much moire impressive.
2. The second case is very interesting. It was mentioned that the obstruction was at 23 cms. So, that
certainly gives enough room from the proximal end of compression to the posterior part of the larynx
unless it is being implied that the esophageal SEMS has somehow migrated proximally which i agree is
very rare. You have mentioned that the tracheal stent was in place but was it confirmed that the
esophageal  SEMS  was  also  in  the  initial  position.  Are  the  authors  also  trying  to  say  that  the
compression of the nerve could be due to the tracheal stent too? Please clarify the above
3. The authors'  second hypothesis involving sever reflux as mechanism seems a little too far fetched
for such a serious acute condition especially considering the GE junction was intact. This can be
omitted I think.
4. I am unable to understand the use of a particular terminology; "superficial polypnea". Please explain.
Are the methods appropriate and well described?
If not, please specify what is required 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.
Unable to assess
Are the conclusions drawn adequately supported by the data shown?
If not, please explain in your comments to the authors.
Yes
Are you able to assess any statistics in the manuscript or would you recommend an additional
statistical review?
If  an  additional  statistical  review  is  recommended,  please  specify  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
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