A pilot study using an infrared imaging system in prevention of post-endoscopic submucosal dissection ulcer bleeding.

BACKGROUND: Endoscopic submucosal dissection (ESD) for superficial gastric neoplasm is a curative method. The aim of this study was to detect potential nonbleeding visible vessels (NBVVs) by using an infrared imaging (IRI) system. METHODS: A total of 24 patients (25 lesions) were consecutively enrolled between March 2010 and December 2010. The day after ESD, endoscopist A (K.M.), who was blinded to the actual procedure of ESD, performed esophagogastroduodenoscopy (EGD) of the post-ESD ulcer base using the IRI system. Endoscopist A marked gray/blue points in the hard-copy images with the IRI system. After the first procedure, endoscopist B (Y.Y.), who was blinded to the results recorded by endoscopist A, performed a second EGD with white light endoscopy and administered water-jet pressure with the maximum level of an Olympus flushing pump onto the post-ESD ulcer base. This test can cause iatrogenic bleeding via application of pressure to NBVV in the post-ESD ulcer. RESULTS: The IRI system detected 58 gray points and 71 blue points. The post-ESD ulcer was divided into the central area and the peripheral area. There were 14 gray points (24 %) in the central area and 44 gray points (76 %) in the peripheral area. There were 19 blue points (27 %) in the central area and 52 blue points (73 %) in the peripheral area. There was no significant difference when comparing the distribution of gray points and blue points. Bleeding occurred with a water-jet pressure in 11 of 58 gray points and in none of the blue points (P = 0.000478). Among the gray points, bleeding in response to a water-jet pressure occurred in 2 points in the central area and in 9 points in the peripheral area. CONCLUSION: The IRI system detects visible vessels (VVs) that are in no need of coagulation as blue points, and VVs have a potential risk of bleeding as gray points.

A randomized crossover open trial of the adenoma miss rate for narrow band imaging (NBI) versus flexible spectral imaging color enhancement (FICE).

PURPOSE: Narrow band imaging (NBI) and flexible spectral imaging color enhancement (FICE) allow improved contrasted evaluation of the mucosal surface. However, no study has compared the utility of these two modalities. Therefore, the aim of this study was to compare the adenoma miss rate (AMR) between NBI and FICE. METHODS: A total of 55 patients (38 men, 17 women) were enrolled in this study. Patients were randomly assigned to the NBI-FICE group (NBI followed by FICE) or the FICE-NBI group (FICE followed by NBI). NBI and FICE total colonic observations were tandemly performed for each patient during the scope withdrawal with white light following cecal intubation. All detected polyps with the NBI or FICE observation were categorized into three groups according to the size and number of polyps missed. RESULTS: Twenty-nine patients were assigned to the NBI-FICE group, and 26 patients were assigned to the FICE-NBI group. There was no significant difference in the overall AMR when comparing the image-enhanced endoscopy technologies (17.9 % for NBI, 26 % for FICE, p = 0.159). AMR was lower for NBI than for FICE for adenomas <5 mm in diameter (5.7 % for NBI, 12.6 % for FICE, p = 0.036). AMR was not significantly different when comparing NBI and FICE for lesions 5 to 10 mm (p = 0.967) or for lesions ≥10 mm (p = 0.269). CONCLUSIONS: This study demonstrated that overall AMR was not different when comparing NBI and FICE.

Magnifying endoscopy combined with narrow band imaging may help to predict neoplasia coexisting with gastric hyperplastic polyps.

BACKGROUND AND STUDY AIM: Although focal cancer occasionally coexists with gastric hyperplastic polyps, previous studies have reported that white light endoscopy (WLE) and biopsy sampling cannot effectively predict the coexistence of cancer. The aim of this study was to elucidate efficacious predictors for cancer coexistence. PATIENTS AND METHODS: This retrospective single academic center study analyzed consecutive patients with gastric polyps diagnosed as hyperplastic before endoscopic resection. Using an image catalog of WLE and magnifying endoscopy combined with narrow band imaging (ME-NBI) performed as part of the preresection work-up, three endoscopists independently assessed the coexistence of cancer and the presence of predefined ME-NBI findings in the microvasculature (MV) and fine mucosal structure (FMS). RESULTS: Twelve of 64 gastric polyps (19%) resected from 51 patients enrolled in the study showed the coexistence of neoplasia. Polyps with coexisting neoplasia were significantly larger than those without (22.6 ± 10.1 vs. 15.5 ± 7.7 mm, respectively). Multivariate analysis of factors significantly associated with the coexistence of neoplasia identified lesion size and three specific endoscopic findings, that is, WLE diagnosis of cancer coexistence, ME-NBI findings of abnormal MV and micrification (size reduction) of the FMS. Combining lesion size (≥20 mm) and ME-NBI findings of FMS micrification had a diagnostic accuracy of 100% sensitivity and 58% specificity for coexisting neoplasia. However, combinations of WLE diagnosis and any other criteria could not achieve a diagnostic sensitivity of 100%. CONCLUSION: ME-NBI enhances the prediction of cancer coexistence in gastric hyperplastic polyps, with lesion size (≥20 mm) and FMS micrification the most effective predictive findings.

Glucagon facilitates colonoscopy and reduces patient discomfort: a randomized double-blind controlled trial with salivary amylase stress analysis.

OBJECTIVE: Randomized placebo-controlled trials on the effectiveness of glucagon in colonoscopy were conducted more than a decade ago and the outcomes varied for each study. Since then, techniques and imaging technology in colonoscopy have steadily improved. The aim of this study was to re-evaluate the effectiveness of glucagon as an antispasmodic, which may facilitate smooth scope intubation and reduce patient discomfort during screening colonoscopy under current equipment settings. METHODS: A total of 70 patients undergoing colonoscopy under conscious sedation were randomized into two groups: a group with intravenous administration of 1 mg glucagon and a placebo group. After colonoscopy, patients completed questionnaires on pain, abdominal fullness, and acceptance of future colonoscopy. Difficulty in scope manipulation was scored by endoscopists, and times for cecal intubation, observation, and the number of polyps detected by colonoscopy were also recorded. In addition, we evaluated patient discomfort objectively with a newly developed portable analyzer of salivary amylase activity. This study was performed double-blind, and assignments were not disclosed to patients or to endoscopists. RESULTS: Scores for acceptance for future colonoscopy, pain, abdominal fullness, and scope manipulation were significantly lower in the glucagon group. Salivary amylase activity, determined at the time the scope was inserted to the cecum, was significantly lower in the glucagon group, and cecal intubation time was significantly shorter in the glucagon group. Observation time and polyp detection rate were not significantly different between the groups. CONCLUSION: These results indicate that intravenous administration of glucagon can reduce patient discomfort and improve scope intubation during screening colonoscopy.

Bacteremia and endotoxemia after endoscopic submucosal dissection for gastric neoplasia: pilot study.

BACKGROUND: Because the invasive procedure of endoscopic submucosal dissection (ESD) entails a large mucosal defect which is left open, with extensive submucosal exposure to the indigenous bacterial flora, the procedure may have a substantial risk for bacteremia. Our aim was to examine gastric ESD-related bacteremia and endotoxemia in gastric neoplasia patients. METHODS: In patients who underwent ESD for superficial gastric neoplasia, blood cultures and plasma endotoxin measurements were done before, immediately after, and on day 2 after ESD. Clinically manifest infections and inflammatory markers, including C-reactive protein (CRP) and white blood cells, were monitored. RESULTS: Fifty patients (aged 69 ± 8 years; mean ± SD) were enrolled. The diameter of the resected specimens was 38 ± 18 mm and the procedure time of ESD was 66 ± 53 min. Two percent (2/100) of blood cultures after ESD were positive, with findings as follows: Propionibacterium species immediately after ESD, and Enterobacter aerogenes on day 2 after ESD, but no clinically manifest infection was observed. In 30% of the enrolled patients, CRP on day 2 after ESD had increased to levels higher than 1.0 mg/l. Plasma endotoxin levels, immediately after and on day 2 after ESD were correlated with CRP levels on day 2 after ESD. CONCLUSIONS: In spite of the invasive procedure with massive submucosal exposure to the indigenous bacterial flora, gastric ESD has a low risk for bacteremia. Gastric ESD-related endotoxemia may be linked to inflammatory reactions such as those shown by the increase of CRP or fever observed after ESD.

Diagnostic utility of narrow-band imaging endoscopy for pharyngeal superficial carcinoma.

AIM: To investigate the endoscopic features of pharyngeal superficial carcinoma and evaluate the utility of narrow-band imaging (NBI) for this disease. METHODS: In the present prospective study, 335 patients underwent conventional white light (CWL) endoscopy and non-magnified/magnified NBI endoscopy, followed by an endoscopic biopsy, for 445 superficial lesions in the oropharynx and hypopharynx. The macroscopic appearance of superficial lesions was categorized as either elevated (< 5 mm in height), flat, or depressed (not ulcerous). Superficial carcinoma (SC) was defined as a superficial lesion showing high-grade dysplasia or squamous cell carcinoma on histology. The color, delineation, and macroscopic appearances of the lesions were evaluated by CWL endoscopy. The ratio of the brownish area/intervascular brownish epithelium (IBE), as well as microvascular proliferation, dilation, and irregularities, was determined by non-magnified/magnified NBI endoscopy. An experienced pathologist who was unaware of the endoscopic findings made the histological diagnoses. By comparing endoscopic findings with histology, we determined the endoscopic features of SC and evaluated the diagnostic utility of NBI. RESULTS: The 445 lesions were divided histologically into two groups: a non-SC group, including non-neoplasia and low-grade dysplasia cases, and an SC group. Of the 445 lesions examined, 333 were classified as non-SC and 112 were classified as SC. There were no significant differences in age, gender, or the location of the lesions between the patients in the two groups. The mean diameter of the SC lesions was significantly greater than that of non-SC lesions (11.0 ± 7.6 mm vs 4.6 ± 3.6 mm, respectively, P < 0.001). Comparisons of CWL endoscopy findings for SC and non-SC lesions by univariate analysis revealed that the incidence of redness (72% vs 41%, respectively, P < 0.001) and a flat or depressed type of lesion (58% vs 44%, respectively, P = 0.013) was significantly higher in the SC group. Using non-magnified NBI endoscopy, the incidence of a brownish area was significantly higher for SC lesions (79% vs 57%, respectively, P < 0.001). On magnified NBI endoscopy, the incidence of IBE (68% vs 33%, P < 0.001) and microvascular proliferation (82% vs 51%, P < 0.001), dilation (90% vs 76%, P = 0.002), and irregularity (82% vs 31%, P < 0.001) was also significantly higher for the SC compared with the non-SC lesions. Multivariate analysis revealed that the incidence of redness (P = 0.022) on CWL endoscopy and IBE (P < 0.001) and microvascular irregularities (P < 0.001) on magnified NBI endoscopy was significantly higher in SC than non-SC lesions. Redness alone exhibited significantly higher sensitivity and significantly lower specificity for the diagnosis of SC compared with redness plus IBE and microvascular irregularities (72% vs 52%, P = 0.002; and 59% vs 92%, P < 0.001, respectively). The accuracy of redness plus IBE and irregularities for the diagnosis of SC was significantly greater than using redness alone (82% vs 62%, respectively, P < 0.001). CONCLUSION: Redness, IBE, and microvascular irregularities appear to be closely related to SC lesions. Magnified NBI endoscopy may increase the diagnostic accuracy of CWL endoscopy for SC.

Isolated thalamic agraphia with impaired grapheme formation and micrographia.

Two patients with isolated thalamic agraphia are described. Both showed kanji (Japanese morphograms) agraphia due to impaired character recall, grapheme deformity and micrographia (progressive reduction in character size during writing) after a lesion that involved the ventral lateral and ventroposterolateral nuclei. Single photon emission computed tomography with a (99m)Tc-ethylcysteinate dimer revealed hypoperfusion in the left precentral gyrus (Brodmann Area 6) and anterior supramarginal gyrus in both. Six months later, the extent of blood flow reduction decreased in the supramarginal gyrus in both patients and the precentral gyrus in patient 1. By this time, the writing impairment improved to nearly the normal range. Our study suggests that kanji agraphia (corresponding to lexical agraphia in Western countries) with poor grapheme formation and micrographia arises from a lesion in the ventral lateral and ventroposterolateral nuclei in the left thalamus. The accompaniment of poor grapheme formation and micrographia may reflect disruption of the cortico-subcortical motor circuit involving the putamen, thalamus, premotor cortex and sensorimotor cortex. It is also suggested that multiple cortical sites can be a target for secondary dysfunction that yields agraphia in a thalamic lesion, and that the recovery of reduced cortical blood flow does not always proceed in parallel with that of agraphia.

Magnifying endoscopy with narrow-band imaging achieves superior accuracy in the differential diagnosis of superficial gastric lesions identified with white-light endoscopy: a prospective study.

BACKGROUND: Conventional, white-light imaging endoscopy (WLE) results in a significant number of misdiagnoses in early gastric cancer. Magnifying endoscopy combined with narrow-band imaging (ME-NBI) is more accurate in the diagnosis of gastric cancer when the diagnostic triad of the disappearance of fine mucosal structure, microvascular dilation, and heterogeneity is used. OBJECTIVE: The aim of the present study was to evaluate the superiority of ME-NBI in the differential diagnosis of superficial gastric lesions identified with conventional WLE. DESIGN: Prospective, comparative study. SETTING: Single academic center. PATIENTS: This study involved patients who underwent WLE and ME-NBI for surveying synchronous or metachronous cancers because they had a high risk of gastric cancer. INTERVENTION: Patients with superficial gastric lesions that were diagnosed by WLE as cancer or non-cancer with a slight suspicion of cancer were prospectively enrolled in the study. ME-NBI was used to further characterize lesions picked up with WLE. MAIN OUTCOME MEASUREMENTS: Sensitivity and specificity for the diagnosis of gastric cancer, with pathology as the criterion standard. RESULTS: A total of 201 lesions (mean diameter [+/- SD] 7.0 +/- 4.0 mm) from 111 patients (98 men, 13 women; mean age 66.3 years) were evaluated. Fourteen of the 201 lesions were pathologically proven as gastric cancer; the others were noncancerous lesions. The sensitivity and specificity for ME-NBI diagnosis with the use of the triad (92.9% and 94.7%, respectively) were significantly better than for WLE (42.9% and 61.0%, respectively; P < .0001). LIMITATIONS: Single center and a highly selected population at high risk for gastric cancer. CONCLUSION: ME-NBI achieved superior accuracy in the differential diagnosis of superficial gastric lesions identified with WLE. Thus, ME-NBI may increase the diagnostic value of endoscopy in a population at high risk of gastric cancer.

Trimodal imaging endoscopy may improve diagnostic accuracy of early gastric neoplasia: a feasibility study.

BACKGROUND: A considerable number of superficial gastric neoplasias are overlooked with conventional white light imaging (WLI) endoscopy. OBJECTIVE: The aim was to investigate the diagnostic potential of trimodal imaging endoscopy (TME), which combines WLI, autofluorescence imaging (AFI), and narrow-band imaging (NBI), for superficial gastric neoplasia. DESIGN: Feasibility study. SETTING: Single academic center. PATIENTS: Sixty-two patients with or without gastric neoplasia. INTERVENTION: Each patient serially assessed with WLI, AFI, and magnifying endoscopy with NBI (ME-NBI) by an endoscopist blinded for clinical information. ME-NBI over WLI and AFI was designated as TME. Histopathology of biopsy and ESD specimens was evaluated and used as the gold standard. MAIN OUTCOME MEASUREMENTS: Sensitivity and specificity of endoscopic diagnosis of pathology-proven neoplasia by per-patient and per-lesion analyses. RESULTS: The study included 47 pathology-proven neoplasias and 44 pathology-proven nonneoplasias that were detected as neoplasias with any of the modalities. By a per-lesion analysis, the sensitivity of TME (89.4%) was higher than that of WLI (76.6%) and AFI (68.1%). The specificity of TME (98.0%) was higher than that of WLI (84.3%) and AFI (23.5%). By a per-patient analysis, the sensitivity of TME (90.9%) was higher than that of WLI (75%) and AFI (68.2%). The specificity of TME (100%) was higher than that of WLI (72.2%) and AFI (44.4%). LIMITATIONS: Case-enriched population at a single center. CONCLUSIONS: Higher diagnostic accuracy of TME over conventional WLI indicates the feasibility of TME for the efficacious diagnosis of early gastric neoplasia.

Ultrathin endoscopy versus high-resolution endoscopy for diagnosing superficial gastric neoplasia.

BACKGROUND: Ultrathin endoscopy (UTE) is an acceptable and cost-effective alternative to EGD with the patient under sedation, although the diagnostic accuracy of UTE is not well established. OBJECTIVE: To compare the diagnostic accuracy of UTE and high-resolution endoscopy (HRE) for superficial gastric neoplasia. DESIGN: Prospective comparative study. SETTING: Academic center. PATIENTS AND INTERVENTIONS: Patients with or without superficial gastric neoplasia underwent peroral UTE and HRE, back-to-back in a random order while under standard sedation. The procedures were performed by 2 endoscopists who were blinded to the clinical information. MAIN OUTCOME MEASUREMENTS: The rate of missed lesions and misdiagnosis, sensitivity, and specificity for the diagnosis of gastric neoplasia when using pathology as the reference standard. RESULTS: In total, 126 lesions (41 superficial gastric neoplasias, 85 nonneoplastic lesions) were recorded in 57 enrolled patients. For the diagnosis of gastric neoplasia, the sensitivity of UTE (58.5%) was significantly (P = .021) lower than that of HRE (78%), and the specificity of UTE (91.8%) was significantly (P = .014) lower than that of HRE (100%). The rate of missed lesions and misdiagnosis of gastric neoplasias when using UTE (41.5%) was significantly (P > .001) higher than that of HRE (22.0%). The corresponding rate of neoplasias at the proximal portion (fornix and corpus) when using UTE (29%) was significantly (P = .002) higher than that of HRE (7.2%), although the rates of neoplasias at the distal portion (angulus and antrum) were comparable for UTE and HRE. LIMITATION: Small sample numbers in an enriched population. CONCLUSIONS: The diagnostic accuracy of UTE is significantly lower than that of HRE for superficial gastric neoplasia, and this difference is particularly striking for neoplasias in the proximal stomach. For UTE to be used as an alternative modality, improvements in optical quality and the incorporation of additional procedures, including close-range observations and chromoendoscopy, are required to enhance visualization.