Comparison of white light and narrow band high definition images in predicting colon polyp histology, using standard colonoscopes without optical magnification.
OBJECTIVE
Narrow band imaging (NBI) with optical magnification is useful in predicting colon polyp histology. As magnifying endoscopes are not routinely available, we investigated the use of NBI and high definition white light imaging in determining polyp histology, using images obtained with colonoscopes without optical magnification.


METHODS
Images (white light and NBI) of colon polyps less than 10 mm in diameter were collected prospectively from patients undergoing screening colonoscopy and digitally stored. Two endoscopists later reviewed all images and predicted polyp histology as neoplastic or non-neoplastic using a modified Kudo classification. Comparison was made with histopathology.


RESULTS
Separate white light and NBI images of 80 polyps (49 neoplastic, 31 non-neoplastic) from 63 patients were recorded. Mean polyp size was 5.1 +/- 2.1 mm (5.4 +/- 2.2 neoplastic; 4.4 +/- 1.8 non-neoplastic; P = 0.02). In a pooled analysis, NBI correctly predicted neoplastic histology in 93 of 98 images (sensitivity 95 %, positive predictive value [PPV] 94 %) whereas white light did so in 58 of 98 images (sensitivity 59 %, PPV 79 %). NBI correctly predicted non-neoplastic histology in 56 of 62 images (specificity 90 %, negative predictive value [NPV] 92 %) whereas white light did so in 47 of 62 images (specificity 76 %, NPV 54 %).


CONCLUSIONS
NBI without optical magnification was more accurate in predicting colon polyp histology compared with white light imaging. Image quality and confidence in histology were significantly higher in the NBI group. NBI without optical magnification may be useful in predicting colon polyp histology.
Sikka
S
S
Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Ringold
D A
DA
Jonnalagadda
S
S
Banerjee
B
B
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000473:pathology*; D003111:Colonic Polyps / Q000473:pathology*; D020685:Colonoscopes; D003113:Colonoscopy; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008027:Light; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results