Could near focus endoscopy, narrow-band imaging, and acetic acid improve the visualization of microscopic features of stomach mucosa?

Figure 1 White light endoscopy from the point of view of the first observer. A and B: White light endoscopy (WLE)-1a pattern and WLE-2a pattern shows a clear appearance of the regular arrangement of collecting venules (RAC) (white arrow); C: WLE-b pattern shows a less clear appearance of the RAC (white arrow); D: WLE-c pattern shows the absence of the RAC.

Figure 2 Near focus mode from the point of view of the first observer. A: Near focus (NF)-a pattern shows a clear appearance of the regular arrangement of collecting venules (white arrow), subepithelial capillary network (SECN) (black arrow), and gastric pits (GP) (square); B: NF-b pattern shows a less clear appearance of the regular arrangement of collecting venules (white arrow) and a clear appearance of the SECN (black arrow) and GP (square); C: NF-c pattern shows a clear appearance of the SECN (black arrow) and GP (square).

Figure 3 Near focus, narrow-band imaging mode from the point of view of the first observer. A and B: Near focus (NF)-narrow-band imaging (NBI)-1a pattern and NF-NBI-2a pattern show a clear appearance of the regular arrangement of collecting venules (white arrow), subepithelial capillary network (black arrow), gastric pits (square), and crypt opening (green arrow, right upper corner); C: NF-NBI-b pattern shows a clear appearance of the subepithelial capillary network (black arrow) and gastric pits (square). A less clear appearance of the crypt opening (green arrow, right upper corner) is observed.

Figure 4 Acetic acid, near focus and acetic acid-near focus, narrow-band imaging mode from the point of view of the first observer. A and B: A1 image [acetic acid (AA)-near focus (NF) pattern] was scored at 0.5; B1 image [AA-NF-narrow-band imaging (NBI) pattern] was scored at 1; A2 image (AA-NF pattern) was scored at 1; B2 image (AA-NF-NBI pattern) was scored at 1; A3 (AA-NF pattern) was scored at 0; B3 image (AA-NF-NBI pattern) was scored at 0.5.