comma before then and sentence structure

[Debra Kirk]

Could someone let me know if I put the comma in the correct place in this sentence?

Upper endoscope is advanced through the esophagus, into the stomach, then through the pylorus into the duodenum.

 

[Rover_KE]

The commas are correct.

The first part of the sentence sounds wrong but I don't know how to to correct it.

Rover

(not a physician)

 

[MikeNewYork]

Could someone let me know if I put the comma in the correct place in this sentence?

Upper endoscope is advanced through the esophagus, into the stomach, then through the pylorus into the duodenum.

I would use an indefinite article (an) before "upper". I would eliminate the comma after "esophagus".

 

[Raymott]

I'd also say that the upper endoscope is being advanced 'down' or 'along' the oesophagus, unless you're describing how to perforate it.

 

[MikeNewYork]

I'd also say that the upper endoscope is being advanced 'down' or 'along' the oesophagus, unless you're describing how to perforate it.

LOL! Good point.