Title: Endoscopic gastrointestinal bypass anastomosis using deformable self-assembled
magnetic anastomosis rings (DSAMARs) in a pig model
Version: 1 Date: 26 Nov 2023
Reviewer's report:
Very good study and novel use of MCA for gastrointestinal bypass anastomosis in case of gastric
outlet obstruction. I want to comment on this novel device and experimental study.
Regarding this device and procedure:
1) One needs to know The height and width of individual magnets, as severe luminal narrowing
sometimes may not allow passage of a 12mm broad trapezoid (Assumed based on inner minus
outer diameter, 25-13=12).
2) Which guidewire and push catheter was used for the procedure? What was the diameter and
length of the guidewire and catheter? Are they specially designed for this procedure? It would
be great if a photo of the entire assembly were given.
3) In real gastric outlet obstruction, can this entire assembly be withdrawn if stricture does not
allow the passage of magnets across it?
4) Once magnets are in a ring shape, is there always attraction between two rings, or can there
be repulsion if they are placed randomly? Is there any specific need to put one surface up and
the other down so there is no repulsion?
5) Regarding the procedure, I suggest providing one video for a better understanding of the
procedure.
6) Was a proton pump inhibitor given post-procedure to decrease the risk of anastomotic site
ulcer and bleeding?
Regarding result and outcome
7) Was the animal model watched for symptoms of bowel obstruction? Two magnet rings of 25
mm diameter can possibly cause bowel obstruction, especially at the ileocecal valve or terminal
ileum.
8) Endoscopy was done after passage of the magnet through the anus, was the diameter of
anastomosis noted? What is anastomosis diameter after necropsy at four weeks? Is there any
discrepancy in sizes to suggest the possibility of restenosis?
9) The mean duration of magnet expulsion was 13 days; immediate feeding was started
in the pig model because they have normal passage through the pylorus. In gastric outlet
obstruction, feeding will be delayed for these days compared to an antral stent for EUS-guided
gastrojejunostomy. This is a limitation of MCA and should included in the limitations of the
study.
Title: Endoscopic gastrointestinal bypass anastomosis using deformable self-assembled
magnetic anastomosis rings (DSAMARs) in a pig model
Version: 1 Date: 26 Nov 2023
Reviewer's report:
Very good study and novel use of MCA for gastrointestinal bypass anastomosis in case of gastric
outlet obstruction. I want to comment on this novel device and experimental study.
Regarding this device and procedure:
1) One needs to know The height and width of individual magnets, as severe luminal narrowing
sometimes may not allow passage of a 12mm broad trapezoid (Assumed based on inner minus
outer diameter, 25-13=12).
2) Which guidewire and push catheter was used for the procedure? What was the diameter and
length of the guidewire and catheter? Are they specially designed for this procedure? It would
be great if a photo of the entire assembly were given.
3) In real gastric outlet obstruction, can this entire assembly be withdrawn if stricture does not
allow the passage of magnets across it?
4) Once magnets are in a ring shape, is there always attraction between two rings, or can there
be repulsion if they are placed randomly? Is there any specific need to put one surface up and
the other down so there is no repulsion?
5) Regarding the procedure, I suggest providing one video for a better understanding of the
procedure.
6) Was a proton pump inhibitor given post-procedure to decrease the risk of anastomotic site
ulcer and bleeding?
Regarding result and outcome
7) Was the animal model watched for symptoms of bowel obstruction? Two magnet rings of 25
mm diameter can possibly cause bowel obstruction, especially at the ileocecal valve or terminal
ileum.
8) Endoscopy was done after passage of the magnet through the anus, was the diameter of
anastomosis noted? What is anastomosis diameter after necropsy at four weeks? Is there any
discrepancy in sizes to suggest the possibility of restenosis?
9) The mean duration of magnet expulsion was 13 days; immediate feeding was started
in the pig model because they have normal passage through the pylorus. In gastric outlet
obstruction, feeding will be delayed for these days compared to an antral stent for EUS-guided
gastrojejunostomy. This is a limitation of MCA and should included in the limitations of the
study.
Please review this paper.
user
Title: Endoscopic gastrointestinal bypass anastomosis using deformable self-assembled
magnetic anastomosis rings (DSAMARs) in a pig model
Version: 1 Date: 26 Nov 2023
Reviewer's report:
Very good study and novel use of MCA for gastrointestinal bypass anastomosis in case of gastric
outlet obstruction. I want to comment on this novel device and experimental study.
Regarding this device and procedure:
1) One needs to know The height and width of individual magnets, as severe luminal narrowing
sometimes may not allow passage of a 12mm broad trapezoid (Assumed based on inner minus
outer diameter, 25-13=12).
2) Which guidewire and push catheter was used for the procedure? What was the diameter and
length of the guidewire and catheter? Are they specially designed for this procedure? It would
be great if a photo of the entire assembly were given.
3) In real gastric outlet obstruction, can this entire assembly be withdrawn if stricture does not
allow the passage of magnets across it?
4) Once magnets are in a ring shape, is there always attraction between two rings, or can there
be repulsion if they are placed randomly? Is there any specific need to put one surface up and
the other down so there is no repulsion?
5) Regarding the procedure, I suggest providing one video for a better understanding of the
procedure.
6) Was a proton pump inhibitor given post-procedure to decrease the risk of anastomotic site
ulcer and bleeding?
Regarding result and outcome
7) Was the animal model watched for symptoms of bowel obstruction? Two magnet rings of 25
mm diameter can possibly cause bowel obstruction, especially at the ileocecal valve or terminal
ileum.
8) Endoscopy was done after passage of the magnet through the anus, was the diameter of
anastomosis noted? What is anastomosis diameter after necropsy at four weeks? Is there any
discrepancy in sizes to suggest the possibility of restenosis?
9) The mean duration of magnet expulsion was 13 days; immediate feeding was started
in the pig model because they have normal passage through the pylorus. In gastric outlet
obstruction, feeding will be delayed for these days compared to an antral stent for EUS-guided
gastrojejunostomy. This is a limitation of MCA and should included in the limitations of the
study.
assistant