Efforts to increase image quality during endoscopy: The role of pronase

Table 2 Summary of studies about premedication with pronase for visualization of the mucosa during advanced endoscopy

Examination	Ref.	Year	Study design	Premedication group (n)	Mucosal visibility
Chromoendoscopy	Fujii et al[8]	1998	Prospective	A: DMPS (34) B: DMPS + SB (32) C: DMPS + SB + pronase (34)	C > A, B
NBI endoscopy	Cha et al[17]	2014	Prospective	A: Pronase + SB (28) B: Simethicone (27)	A > B
ME-NBI	Kim et al[7]	2015	Prospective	A: Simethicone + SB + pronase (71) B: Simethicone (72)	A > B
EUS	Sakai et al[24]	2003	Prospective	A: DMPS (29) B: DMPS + SB (29) C: DMPS + SB + pronase (29)	C > A, B
	Han et al[25]	2011	Prospective	A: Saline (60) B: Pronase + SB (62) C: Pronase + SB + simethicone (61)	B > A > C

NBI: Narrow-band imaging; ME-NBI: Magnifying endoscopy with narrow-band imaging; EUS: Endoscopic ultrasonography; DMPS: Dimethylpolysiloxane; SB: Sodium bicarbonate.