Magnifying colonoscopy as a non-biopsy technique for differential diagnosis of non-neoplastic and neoplastic lesions

AIM： To clarify whether mucosal crypt patterns observed with magnifying colonoscopy are feasible to distinguish non-neoplastic polyps from neoplastic polyps. METHODS： From June 1999 through March 2000, 180 consecutive patients with 210 lesions diagnosed with a magnifying colonoscope （CF-200Z, Olympus Optical Co., Ltd., Tokyo, Japan） were enrolled. Magnification and chromoendoscopy with 0.2% indigo-carmine dye was applied to each lesion for mucosal crypt observation. Lesions showing types Ⅰ and Ⅱ crypt patterns were considered non-neoplastic and examined histologically by biopsy, whereas lesions showing types Ⅲ to Ⅴ crypt patterns were removed endoscopically or surgically. The correlation of endoscopic diagnosis and histologic diagnosis was then investigated. RESULTS： At endoscopy, 24 lesions showed a type Ⅰ or Ⅱ pit pattern, and 186 lesions showed type Ⅲ to Ⅴ pit patterns. With histologic examination, 26 lesions were diagnosed as non-neoplastic polyps, and 184 lesions were diagnosed as neoplastic polyps. The overall diagnostic accuracy was 99.1% （208/210）. The sensitivity and specificity were 92.3% （24/26） and 99.8% （184/186）, respectively. CONCLUSION： Magnifying colonoscopy could be used as a non-biopsy technique for differentiating neoplastic and non-neoplastic polyps.

Magnifying chromoscopy, a novel and useful technique for colonoscopy in ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disorder characterized by exacerbations and remissions. The degree of inflammation as assessed by conventional colonoscopy is a reliable parameter of disease activity. However, even when conventional colonoscopy suggests remission and normal mucosal findings, microscopic abnormalities may persist, and relapse may occur later. Patients with long-standing, extensive ulcerative colitis have an increased risk of developing colorectal cancer. Ulcerative colitis-associated colorectal cancer is characterized by an early age at onset, poorly differentiated tumor cells, mucinous carcinoma, and multiple lesions. Early detection of dysplasia and colitic cancer is thus a prerequisite for survival. A relatively new method, magnifying chromoscopy, is thought to be useful for the early detection and diagnosis of dysplasia and colitic cancer, as well as the prediction of relapse.

Evaluation of magnifying colonoscopy in the diagnosis of serrated polyps

AIM:To elucidate the colonoscopic features of serrated lesions of the colorectum using magnifying colonoscopy.METHODS:Broad division of serrated lesions of the colorectum into hyperplastic polyps(HPs),traditional serrated adenomas(TSAs),and sessile serrated adenomas/polyps(SSA/Ps) has been proposed on the basis of recent molecular biological studies.However,few reports have examined the colonoscopic features of these divisions,including magnified colonoscopic findings.This study examined 118 lesions excised in our hospital as suspected serrated lesions after magnified observation between January 2008 and September 2011.Patient characteristics(sex,age),conventional colonoscopic findings(location,size,morphology,color,mucin) and magnified colonoscopic findings(pit pattern diagnosis) were interpreted by five colonoscopists with experience in over 1000 colonoscopies,and were compared with histopathological diagnoses.The pit patterns were categorized according to Kudo's classification,but a more detailed investigation was also performed using the subclassification [type Ⅱ-Open(type Ⅱ-O),type Ⅱ-Long(type Ⅱ-L),or type Ⅳ-Serrated(type Ⅳ-S)] proposed by Kimura T and Yamano H.RESULTS:Lesions comprised 23 HPs(23/118:19.5%),39 TSAs(39/118:33.1%:with cancer in one case),50 SSA/Ps(50/118:42.4%:complicated with cancer in three cases),and six others(6/118:5.1%).We excluded six others,including three regular adenomas,one hamartoma,one inflammatory polyp,and one juvenile polyp for further analysis.Conventional colonoscopy showed that SSA/Ps were characterized as larger in diameter than TSAs and HPs(SSA/P vs HP,13.62 ± 8.62 mm vs 7.74 ± 3.24 mm,P < 0.001;SSA/Ps vs TSA,13.62 ± 8.62 mm vs 9.89 ± 5.73 mm,P < 0.01);common in the right side of the colon [HPs,30.4%(7/23):TSAs,20.5%(8/39):SSA/P,84.0%(42/50),P < 0.001];flat-elevated lesion [HPs,30.4%(7/23):TSAs,5.1%(2/39):SSA/Ps,90.0%(45/50),P < 0.001];normal-colored or pale imucosa [HPs,34.8%(8/23):TSAs,10.3%(4/39):SSA/Ps,80%(40/50),P < 0.001];and with large amounts of mucin [HPs,21.7%(5/23):TSAs,17.9%(7/39):SSA/Ps,72.0%(36/50),P < 0.001].In magnified colonoscopic findings,17 lesions showed either type Ⅱ pit pattern alone or partial type Ⅱ pit pattern as the basic architecture,with 14 HPs(14/17,70.0%) and 3 SSA/Ps.Magnified colonoscopy showed the type Ⅱ-O pit pattern as characteristic of SSA/Ps [sensitivity 83.7%(41/49),specificity 85.7%(54/63)].Cancer was also present in three lesions,in all of which a type Ⅵ pit pattern was also present within the same lesion.There were four HPs and four TSAs each.The type Ⅳ-S pit pattern was characteristic of TSAs [sensitivity 96.7%(30/31),specificity 89.9%(72/81)].Cancer was present in one lesion,in which a type Ⅵ pit pattern was also present within the same lesion.In our study,serrated lesions of the colorectum also possessed the features described in previous reports of conventional colonoscopic findings.The pit pattern diagnosis using magnifying colonoscopy,particularly magnified colonoscopic findings using subclassifications of surface architecture,reflected the pathological characteristics of SSA/Ps and TSAs,and will be useful for colonoscopic diagnosis.CONCLUSION:We suggest that this system could be a good diagnostic tool for SSA/Ps using magnifying colonoscopy.

Validation of Fujinon intelligent chromoendoscopy with high definition endoscopes in colonoscopy

AIM:To validate high definition endoscopes with Fujinon intelligent chromoendoscopy(FICE) in colonoscopy.METHODS:The image quality of normal white light endoscopy(WLE),that of the 10 available FICE filters and that of a gold standard(0.2% indigo carmine dye) were compared.RESULTS:FICE-filter 4 [red,green,and blue(RGB) wavelengths of 520,500,and 405 nm,respectively] provided the best images for evaluating the vascular pattern compared to white light.The mucosal surface was best assessed using filter 4.However,the views obtained were not rated significantly better than those observed with white light.The "gold standard",indigo carmine(IC) dye,was found to be superior to both white light and filter 4.Filter 6(RGB wavelengths of 580,520,and 460 nm,respectively) allowed for exploration of the IC-stained mucosa.When assessing mucosal polyps,both FICE with magnification,and magnification following dye spraying were superior to the same techniques without magnification and to white light imaging.In the presence of suboptimal bowel preparation,observation with the FICE mode was possible,and endoscopists considered it to be superior to observation with white light.CONCLUSION:FICE-filter 4 with magnification improves the image quality of the colonic vascular patterns obtained with WLE.