Reviewer’s report
Title: 
Utility and safety of a new uneven double-lumen sphincterotome in cases
of difficult biliary cannulation
Version: 
0 
Date: 
03 Sep 2020
Reviewer's report:
With great interest studied the new advancement in ERCP field in your study.
Very few published reports exist of usage of uneven cannula(PIOLAX in
Billroth anatomy, Haber RAMP catheter for intrahepatic duct cannulation).
Uneven sphincterotome (magictome) in your study may be a first report. Here
are the comments 
1. The main aim of various evolving instruments and techniques is to achieve
successful biliary cannulation(utility) which is the rate limiting step and thereby
reduce the complications such as pancreatitis(safety). In the present study,
authors failed to show any significant difference in cannulation success or
occurrence of PEP between the new instrument and conventional catheter.
2. It is a retrospective study with difference in time zone between groups (2013-
2018 vs 2018 -2020). With passage of time, there will be improvement in the
expertise of ERCPist and technician, refinement of instruments, emergence of
new definitions {difficult cannulation (5min,5 attempts)} and new data [PEP
prevention techniques(rectal indomethacin, PDstenting)]. It would be always
pertinent to include cases and controls in the same time zone to reduce these
biases.
3. There is enough evidence to show that cannulation with sphincterotome is
better than the catheter(cannula). Worldwide practices have been changed to
sphincterotome first approach except in selected situations where catheter is
used. Present study compared new kind of sphincterotome with conventional
catheter. It would have been fitting if comparision is between regular
sphincterotome and magictome in terms of cannulation success and cannulation
time. This would have made it possible to take up repeated studies on same
parameters.
4. Risk factors for PEP include more than one guidewire passage. In the present
study, another guidewire is passed which comes out of magictome at an
angle(not aligned to MPD axis) into the pancreatic duct which may significantly
increase PEP risk.
5. In recent Cochrane systemic review , it was shown that no improvement in
successful cannulation with double guidewire technique but there is increased
rate in PEP. Measure taken to prevent PEP in controls and cases have not been
discussed by the authors. 
6. Papillary edema with meddling of papilla has been mentioned by the authors
in the study as contributing to PEP. Even with shorter time, angulating the
magictome with it being fixed by pancreatic guidewire near ampulla did not
reduce PEP. PD stenting is one of the most studied measure in PEP prevention.
PD stent placement is left to the discretion of endoscopist and very few patients
received PD stenting.
7. In the present study, only significant difference authors found was the shorter
time of total biliary cannulation and shortened time from PD to CBD
cannulation. The minimum total biliary cannulation time by magictome was 6.5
min (>5min), which may explain the non reduction of PEP. More number of
guidewire passages or deep guidewire passage without loop into MPD have been
identified as risk factors for PEP and not indwelling time of pancreatic guidewire
as mentioned by the authors.
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find the details of processing in Publons’ privacy policy
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No
Declaration of competing interests
Please complete a declaration of competing interests, considering the following
questions:
1
. 
Have you in the past five years received reimbursements, fees, funding, or
salary from an organisation that may in any way gain or lose financially
from the publication of this manuscript, either now or in the future?
2
. 
Do you hold any stocks or shares in an organisation that 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 interests 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
Reviewer Publication Consent.
 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
) if this manuscript is accepted for
publication. Any comments that I do not wish to be included in the published
report have been included as confidential comments to the editor, which will not
be published.
If you are not happy for us to publish this report, please contact the editorial
office before completing the review.
If you wish, you can include your name in your published report. Please note
you must decide whether to include your name at the start of the process and
confirm this decision whenever prompted. If you change your decision later, we
will not be able to publish your name.
I agree to the terms of the CC-BY 4.0 license; please 
do not
 publish my name
with my report. (default)
Is the study design appropriate to answer the research question (including the use
of appropriate controls), and are the conclusions supported by the evidence
presented?
No
Are the methods sufficiently described to allow the study to be repeated?
No
Is the use of statistics and treatment of uncertainties appropriate?
No
Is the presentation of the work clear?
Yes
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
Yes
Reviewer’s report
Title: 
Utility and safety of a new uneven double-lumen sphincterotome in cases
of difficult biliary cannulation
Version: 
0 
Date: 
03 Sep 2020
Reviewer's report:
With great interest studied the new advancement in ERCP field in your study.
Very few published reports exist of usage of uneven cannula(PIOLAX in
Billroth anatomy, Haber RAMP catheter for intrahepatic duct cannulation).
Uneven sphincterotome (magictome) in your study may be a first report. Here
are the comments 
1. The main aim of various evolving instruments and techniques is to achieve
successful biliary cannulation(utility) which is the rate limiting step and thereby
reduce the complications such as pancreatitis(safety). In the present study,
authors failed to show any significant difference in cannulation success or
occurrence of PEP between the new instrument and conventional catheter.
2. It is a retrospective study with difference in time zone between groups (2013-
2018 vs 2018 -2020). With passage of time, there will be improvement in the
expertise of ERCPist and technician, refinement of instruments, emergence of
new definitions {difficult cannulation (5min,5 attempts)} and new data [PEP
prevention techniques(rectal indomethacin, PDstenting)]. It would be always
pertinent to include cases and controls in the same time zone to reduce these
biases.
3. There is enough evidence to show that cannulation with sphincterotome is
better than the catheter(cannula). Worldwide practices have been changed to
sphincterotome first approach except in selected situations where catheter is
used. Present study compared new kind of sphincterotome with conventional
catheter. It would have been fitting if comparision is between regular
sphincterotome and magictome in terms of cannulation success and cannulation
time. This would have made it possible to take up repeated studies on same
parameters.
4. Risk factors for PEP include more than one guidewire passage. In the present
study, another guidewire is passed which comes out of magictome at an
angle(not aligned to MPD axis) into the pancreatic duct which may significantly
increase PEP risk.
5. In recent Cochrane systemic review , it was shown that no improvement in
successful cannulation with double guidewire technique but there is increased
rate in PEP. Measure taken to prevent PEP in controls and cases have not been
discussed by the authors. 
6. Papillary edema with meddling of papilla has been mentioned by the authors
in the study as contributing to PEP. Even with shorter time, angulating the
magictome with it being fixed by pancreatic guidewire near ampulla did not
reduce PEP. PD stenting is one of the most studied measure in PEP prevention.
PD stent placement is left to the discretion of endoscopist and very few patients
received PD stenting.
7. In the present study, only significant difference authors found was the shorter
time of total biliary cannulation and shortened time from PD to CBD
cannulation. The minimum total biliary cannulation time by magictome was 6.5
min (>5min), which may explain the non reduction of PEP. More number of
guidewire passages or deep guidewire passage without loop into MPD have been
identified as risk factors for PEP and not indwelling time of pancreatic guidewire
as mentioned by the authors.
Publons Reviewer Recognition
. Springer Nature can send verification of this
review directly to Publons (a subsidiary of Clarivate Analytics). If you would
like to take advantage of this service, please click on the “Yes” option below.
Your name, email address, title of the reviewed manuscript, name of the journal,
and date of your review submission (the “Review Data”) will then be transmitted
to Publons after the final decision on the manuscript has been made. If you have
already registered at Publons, they will notify you of the receipt of this review
and update your profile 
as per your settings and their policy. If you are not
registered with Publons, you will receive an email from them asking you to
register in order for them to be able to recognize your review on your new
profile page. Publons may use the Review Data to generate derivative metadata
for the benefit of Publons and you as a reviewer, carefully considering the
sensitivity of such information. For example, Publons may verify your record as
a reviewer by updating your profile published on its webservice if you have
registered for such service or help editors to identify candidate reviewers. Please
find the details of processing in Publons’ privacy policy
https://publons.com/about/terms
No
Declaration of competing interests
Please complete a declaration of competing interests, considering the following
questions:
1
. 
Have you in the past five years received reimbursements, fees, funding, or
salary from an organisation that may in any way gain or lose financially
from the publication of this manuscript, either now or in the future?
2
. 
Do you hold any stocks or shares in an organisation that 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 interests 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
Reviewer Publication Consent.
 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
) if this manuscript is accepted for
publication. Any comments that I do not wish to be included in the published
report have been included as confidential comments to the editor, which will not
be published.
If you are not happy for us to publish this report, please contact the editorial
office before completing the review.
If you wish, you can include your name in your published report. Please note
you must decide whether to include your name at the start of the process and
confirm this decision whenever prompted. If you change your decision later, we
will not be able to publish your name.
I agree to the terms of the CC-BY 4.0 license; please 
do not
 publish my name
with my report. (default)
Is the study design appropriate to answer the research question (including the use
of appropriate controls), and are the conclusions supported by the evidence
presented?
No
Are the methods sufficiently described to allow the study to be repeated?
No
Is the use of statistics and treatment of uncertainties appropriate?
No
Is the presentation of the work clear?
Yes
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
Yes
Please review this paper.
user
Reviewer’s report
Title: 
Utility and safety of a new uneven double-lumen sphincterotome in cases
of difficult biliary cannulation
Version: 
0 
Date: 
03 Sep 2020
Reviewer's report:
With great interest studied the new advancement in ERCP field in your study.
Very few published reports exist of usage of uneven cannula(PIOLAX in
Billroth anatomy, Haber RAMP catheter for intrahepatic duct cannulation).
Uneven sphincterotome (magictome) in your study may be a first report. Here
are the comments 
1. The main aim of various evolving instruments and techniques is to achieve
successful biliary cannulation(utility) which is the rate limiting step and thereby
reduce the complications such as pancreatitis(safety). In the present study,
authors failed to show any significant difference in cannulation success or
occurrence of PEP between the new instrument and conventional catheter.
2. It is a retrospective study with difference in time zone between groups (2013-
2018 vs 2018 -2020). With passage of time, there will be improvement in the
expertise of ERCPist and technician, refinement of instruments, emergence of
new definitions {difficult cannulation (5min,5 attempts)} and new data [PEP
prevention techniques(rectal indomethacin, PDstenting)]. It would be always
pertinent to include cases and controls in the same time zone to reduce these
biases.
3. There is enough evidence to show that cannulation with sphincterotome is
better than the catheter(cannula). Worldwide practices have been changed to
sphincterotome first approach except in selected situations where catheter is
used. Present study compared new kind of sphincterotome with conventional
catheter. It would have been fitting if comparision is between regular
sphincterotome and magictome in terms of cannulation success and cannulation
time. This would have made it possible to take up repeated studies on same
parameters.
4. Risk factors for PEP include more than one guidewire passage. In the present
study, another guidewire is passed which comes out of magictome at an
angle(not aligned to MPD axis) into the pancreatic duct which may significantly
increase PEP risk.
5. In recent Cochrane systemic review , it was shown that no improvement in
successful cannulation with double guidewire technique but there is increased
rate in PEP. Measure taken to prevent PEP in controls and cases have not been
discussed by the authors. 
6. Papillary edema with meddling of papilla has been mentioned by the authors
in the study as contributing to PEP. Even with shorter time, angulating the
magictome with it being fixed by pancreatic guidewire near ampulla did not
reduce PEP. PD stenting is one of the most studied measure in PEP prevention.
PD stent placement is left to the discretion of endoscopist and very few patients
received PD stenting.
7. In the present study, only significant difference authors found was the shorter
time of total biliary cannulation and shortened time from PD to CBD
cannulation. The minimum total biliary cannulation time by magictome was 6.5
min (>5min), which may explain the non reduction of PEP. More number of
guidewire passages or deep guidewire passage without loop into MPD have been
identified as risk factors for PEP and not indwelling time of pancreatic guidewire
as mentioned by the authors.
Publons Reviewer Recognition
. Springer Nature can send verification of this
review directly to Publons (a subsidiary of Clarivate Analytics). If you would
like to take advantage of this service, please click on the “Yes” option below.
Your name, email address, title of the reviewed manuscript, name of the journal,
and date of your review submission (the “Review Data”) will then be transmitted
to Publons after the final decision on the manuscript has been made. If you have
already registered at Publons, they will notify you of the receipt of this review
and update your profile 
as per your settings and their policy. If you are not
registered with Publons, you will receive an email from them asking you to
register in order for them to be able to recognize your review on your new
profile page. Publons may use the Review Data to generate derivative metadata
for the benefit of Publons and you as a reviewer, carefully considering the
sensitivity of such information. For example, Publons may verify your record as
a reviewer by updating your profile published on its webservice if you have
registered for such service or help editors to identify candidate reviewers. Please
find the details of processing in Publons’ privacy policy
https://publons.com/about/terms
No
Declaration of competing interests
Please complete a declaration of competing interests, considering the following
questions:
1
. 
Have you in the past five years received reimbursements, fees, funding, or
salary from an organisation that may in any way gain or lose financially
from the publication of this manuscript, either now or in the future?
2
. 
Do you hold any stocks or shares in an organisation that 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 interests 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
Reviewer Publication Consent.
 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
) if this manuscript is accepted for
publication. Any comments that I do not wish to be included in the published
report have been included as confidential comments to the editor, which will not
be published.
If you are not happy for us to publish this report, please contact the editorial
office before completing the review.
If you wish, you can include your name in your published report. Please note
you must decide whether to include your name at the start of the process and
confirm this decision whenever prompted. If you change your decision later, we
will not be able to publish your name.
I agree to the terms of the CC-BY 4.0 license; please 
do not
 publish my name
with my report. (default)
Is the study design appropriate to answer the research question (including the use
of appropriate controls), and are the conclusions supported by the evidence
presented?
No
Are the methods sufficiently described to allow the study to be repeated?
No
Is the use of statistics and treatment of uncertainties appropriate?
No
Is the presentation of the work clear?
Yes
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
Yes
assistant