Imaging based on photoacoustic effect relies on illuminating with short light pulses absorbed by tissue absorbers, resulting in thermoelastic expansion, giving rise to ultrasonic waves. The ultrasonic waves are then detected by detectors placed around the sample. Photoacoustic endoscopy (PAE) is one of four major implementations of photoacoustic tomography that have been developed recently. The prototype PAE was based on scanning mirror system that deflected both the light and the ultrasound. A recently developed mini-probe was further miniaturized, and enabled simultaneous photoacoustic and ultrasound imaging. This PAE-endoscopic ultrasound (EUS) system can offer high-resolution vasculature information in the gastrointestinal (GI) tract and display differences between optical and mechanical contrast compared with single-mode EUS. However, PAE for endoscopic GI imaging is still at the preclinical stage. In this commentary, we describe the technological improvements in PAE for possible clinical application in endoscopic GI imaging. In addition, we discuss the technical details of the ultrasonic transducer incorporated into the photoacoustic endoscopic probe.
Photoacoustic techniques; Tomography; Endoscopy; Endosonography; Gastrointestinal neoplasm
The incidence of rectal carcinoids is rising because of the widespread use of screening colonoscopy. Rectal carcinoids detected incidentally are usually in earlier stages at diagnosis. Rectal carcinoids estimated endoscopically as < 10 mm in diameter without atypical features and confined to the submucosal layer can be removed endoscopically. Here, we review the efficacy and safety of various endoscopic treatments for small rectal carcinoid tumors, including conventional polypectomy, endoscopic mucosal resection (EMR), cap-assisted EMR (or aspiration lumpectomy), endoscopic submucosal resection with ligating device, endoscopic submucosal dissection, and transanal endoscopic microsurgery. It is necessary to carefully choose an effective and safe primary resection method for complete histological resection.
Carcinoid tumor; Rectum; Polypectomy; Endoscopic mucosal resection; Endoscopic submucosal dissection
Endoscopic band ligation (EBL) is the preferred endoscopic technique for the endoscopic treatment of acute esophageal variceal bleeding. EBL has also been used to treat nonvariceal bleeding. Recently, Han et al demonstrated that EBL can be a feasible and safe alternate technique for the management of iatrogenic gastric perforation especially in cases in which closure with endoclips is difficult. EBL is technically simpler to perform than other methods and provides a good view of the lesions under direct pressure and suction from the transparent ligation cap. EBL can be used even if the diameter of the perforation is greater than 10 mm or if there is a severe tangential angle. In this commentary, we discuss the efficacy and safety of EBL for the closure of iatrogenic gastrointestinal perforation. We also discuss the advantages and disadvantages of EBL for the treatment of nonvariceal bleeding.
Band ligation; Endoscopy; Intestinal perforation; Gastrointestinal hemorrhage
Colonic lipomas are submucosal nonepithelial tumors covered by intact or eroded mucosa. In rare cases, alterations in the mucosa covering a lipoma include hyperplasia, adenoma, atrophy, ulceration, and necrosis. Here, we report a case of a colonic lipoma covered by hyperplastic epithelium in a 68-year-old woman. Based on the colonoscopy findings, a snare polypectomy was performed for a presumptive diagnosis of an epithelial lesion; however, the histological examination revealed a colonic submucosal lipoma with overlying hyperplastic epithelium.
Lipoma; Colonic lipomas; Hyperplastic; Colonoscopy
Boerhaave’s syndrome is spontaneous rupture of the esophagus, a rare condition with high mortality that occurs most often after forceful vomiting. Polyethylene glycol (PEG) solution is the most common preparation used for colonoscopy. Since large volumes have to be ingested, PEG may induce severe vomiting or retching. However, Boerhaave’s syndrome has rarely been reported as a potential problem related to PEG solution. We report a case of spontaneous esophageal rupture due to violent vomiting during bowel preparation with PEG solution in a patient with postpolypectomy bleeding.
Esophageal perforation; Colonoscopy; Polyethylene glycols
Molecular imaging has emerged as a new discipline in gastrointestinal endoscopy. This technology encompasses modalities that can visualize disease-specific morphological or functional tissue changes based on the molecular signature of individual cells. Molecular imaging has several advantages including minimal damage to tissues, repetitive visualization, and utility for conducting quantitative analyses. Advancements in basic science coupled with endoscopy have made early detection of gastrointestinal cancer possible. Molecular imaging during gastrointestinal endoscopy requires the development of safe biomarkers and exogenous probes to detect molecular changes in cells with high specificity anda high signal-to-background ratio. Additionally, a high-resolution endoscope with an accurate wide-field viewing capability must be developed. Targeted endoscopic imaging is expected to improve early diagnosis and individual therapy of gastrointestinal cancer.
Autofluorescence endoscopy; Confocal endomicroscopy; Endoscopy; Molecular imaging; Molecular probes, Near-infrared fluorescence imaging; Targeted endoscopic imaging
Acute respiratory distress syndrome is a life-threatening disorder caused mainly by pneumonia. Clostridium difficile infection (CDI) is a common nosocomial diarrheal disease. Disruption of normal intestinal flora by antibiotics is the main risk factor for CDI. The use of broad-spectrum antibiotics for serious medical conditions can make it difficult to treat CDI complicated by acute respiratory distress syndrome. Fecal microbiota transplantation is a highly effective treatment in patients with refractory CDI. Here we report on a patient with refractory CDI and acute respiratory distress syndrome caused by pneumonia who was treated with fecal microbiota transplantation.
Clostridium difficile infection; Acute respiratory distress syndrome; Fecal microbiota transplantation
Background/Aim. Autophagy, a cellular degradation process, has paradoxical roles in tumorigenesis and the progression of human cancers. The aim of this study was to investigate the expression levels of autophagy-related proteins in colorectal cancer (CRC) and to evaluate their prognostic significance. Methods. This study is a retrospective review of immunohistochemical and clinicopathological data. All specimens evaluated were obtained from 263 patients with colorectal cancer who had undergone surgery between November 1996 and August 2007. The primary outcomes measured were the expression levels of three autophagy-related proteins (ATG5, BECN1/Beclin 1, and Microtubule-associated protein 1 light chain 3B (LC3B)) by immunohistochemistry and its association in clinicopathological parameters and patient survival. Results. The autophagy-related protein expression frequencies were 65.1% (151/232) for ATG5, 71.3% (174/244) for BECN1, and 74.7% (186/249) for LC3B for the 263 patients. Correlation between the expression of autophagy-related proteins was significant for all protein pairs. Multivariate analysis showed that negative LC3B expression and absence of autophagy-related proteins expression were independently associated with poor prognosis. Conclusion. Absence of autophagy-related proteins expression is associated with poor clinical outcome in CRC, suggesting that these proteins have potential uses as novel prognostic markers.
Congenital absence of the pericardium is a rare cardiac malformation and is most often asymptomatic. It is usually discovered as an incidental finding. Physical examination, chest radiography, and electrocardiogram are often unremarkable. Echocardiography provides valuable information, and sometimes computed tomography or magnetic resonance imaging is needed for subsequent confirmation.
Absence of the pericardium; Complete defect; Partial defect
Migraine is frequently accompanied by symptoms consistent with functional gastrointestinal disorders (FGIDs). This study evaluated the prevalence of functional gastrointestinal symptoms and assessed the symptoms' relationship with the concomitant functional symptoms of anxiety, depression, and headache-related disability.
This prospective study included 109 patients with migraine who were recruited from a headache clinic at a teaching hospital. The participants completed a self-administered survey that collected information on headache characteristics, functional gastrointestinal symptoms (using Rome III criteria to classify FGID), anxiety, depression, and headache-related disability.
In total, 71% of patients met the Rome III criteria for at least one FGID. In patients with FGID, irritable bowel syndrome was the most common symptom (40.4%), followed by nausea and vomiting syndrome (24.8%) and functional dyspepsia (23.9%). Depression and anxiety scores were significantly higher in patients meeting the criteria for any FGID. The number of the symptoms consistent with FGID in individual patients correlated positively with depression and anxiety.
FGID symptoms defined by the Rome III criteria are highly prevalent in migraine. These symptoms correlate with psychological comorbidities, such as depression and anxiety.
Gastrointestinal diseases; Migraine disorders; Prevalence; Psychological comorbidity; Headache-related disability
Background/Aim. Bax-interacting factor-1 (Bif-1) plays a crucial role in apoptosis and autophagy. The aim of this study was to evaluate Bif-1 protein expression and its prognostic significance in colorectal cancer (CRC). Methods. We analyzed Bif-1 protein expression in 251 resected specimens from patients with CRC by immunohistochemistry using tissue microarray. Results. Low Bif-1 expression was observed in 131 patients (52.2%) and high Bif-1 expression in 120 patients (47.8%). No significant differences were observed in clinicopathological parameters between patients with high and low Bif-1 expression. Kaplan-Meier survival analysis showed no difference in survival between patients with high and low Bif-1 expression. Stratified analysis of Bif-1 according to TNM stage demonstrated that low Bif-1 expression was significantly associated with a poor outcome in patients with stages I and II (P = 0.034). Stratified multivariate analysis demonstrated that low Bif-1 expression was an independent indicator of poor prognosis (hazard ratio, 0.459; 95% confidence interval, 0.285–0.739; P = 0.001). Conclusion. Patients with low levels of Bif-1 expression have shortened survival rates in CRC of stages I and II. This suggests that Bif-1 protein expression may be a useful prognostic marker in early-stage CRC.
RNA interference (RNAi) is a gene regulation mechanism initiated by RNA molecules that enables sequence-specific gene silencing by promoting degradation of specific mRNAs. Molecular therapy using small interfering RNA (siRNA) has shown great therapeutic potential for diseases caused by abnormal gene overexpression or mutation. The major challenges to application of siRNA therapeutics include the stability and effective delivery of siRNA in vivo. Important progress in nanotechnology has led to the development of efficient siRNA delivery systems. In this review, the authors discuss recent advances in nanoparticle-mediated siRNA delivery and the application of siRNA in clinical trials for cancer therapy. This review will also offer perspectives on future applications of siRNA therapeutics.
Background/Aim. Hepcidin, an iron regulatory hormone, is increased in response to inflammation and some infections. We investigated the relationships among serum prohepcidin, iron status, Helicobacter pylori infection status, and the presence of gastric mucosal atrophy. Methods. Seventy subjects undergoing esophagogastroduodenoscopy underwent multiple gastric biopsies, and the possibility of H. pylori infection and the degree of endoscopic and histologic gastritis were investigated. In all subjects, serum prohepcidin and iron parameters were evaluated. Results. No correlations were observed between serum prohepcidin levels and the other markers of anemia, such as hemoglobin, serum iron, ferritin, and total iron binding capacity. Serum prohepcidin levels were not significantly different between the H. pylori-positive group and the H. pylori-negative group. Serum prohepcidin levels in atrophic gastritis patients were significantly lower than those in subjects without atrophic gastritis irrespective of H. pylori infection. Conclusion. Serum prohepcidin levels were not altered by H. pylori infection. Serum prohepcidin levels decrease in patients with atrophic gastritis, irrespective of H. pylori infection. It suggests that hepcidin may decrease due to gastric atrophy, a condition that causes a loss of hepcidin-producing parietal cells. Further investigations with a larger number of patients are necessary to substantiate this point.
Air in the main pancreatic duct has been reported only rarely and might be associated with either a spontaneous or a surgically induced alteration of the anatomy of the biliary tract. We report a case of “innocent” air found incidentally in the main pancreatic duct. To our knowledge, this is only the third such case reported. A 54-year-old woman presented with hemoptysis that had lasted for 3 d. She underwent a chest computed tomography scan, which revealed not only focal bronchiectasis in the left lower lobe, but also air in the main pancreatic duct and dilatation of the common bile duct. She was managed conservatively for the hemoptysis and no further problems developed. She had no specific gastrointestinal symptoms and had no history of surgery or medication. Her laboratory parameters were normal. Magnetic resonance cholangiopancreatography also demonstrated air in the main pancreatic duct and a dilated common bile duct (CBD). Duodenoscopy revealed separate biliary and pancreatic orifices with patulous openings and some air bubbles appearing in the pancreatic orifice. Endoscopic retrograde cholangiopancreatography (ERCP) showed the dilated CBD and pancreatic duct with some air bubbles, but no other abnormal lesions. She was discharged with no further problems. Most patients with air in the main pancreatic duct have had a pancreatobiliary disease, or a history of pancreatobiliary disease, pancreatobiliary surgery or sphincterotomy. If the air is innocent, as in our case, ERCP should be performed to evaluate any altered sphincteric function or anatomy such as patulous openings.
Air; Main pancreatic duct; Endoscopic retrograde cholangiopancreatography
Peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor that is important in many physiological and pathological processes, such as lipid metabolism, insulin sensitivity, inflammation, cell proliferation, and carcinogenesis. Several studies have shown that PPARγ plays an important role in gastric mucosal injury due to Helicobacter pylori (H. pylori). As H. pylori infection is the main etiologic factor in chronic gastritis and gastric cancer, understanding of the potential roles of PPARγ in H. pylori infection may lead to the development of a therapeutic target. In this paper, the authors discuss the current knowledge on the role of PPARγ in H. pylori infection and its related gastric carcinogenesis.
Recent data from Western populations have suggested that patients with sporadic duodenal adenomas are at a higher risk for the development of colorectal neoplasia. In this study, we compared the frequency of colorectal neoplasia in patients with sporadic duodenal adenomas to healthy control subjects.
This retrospective case-control study used the databases of 3 teaching hospitals in Gyeonggi-do Province, South Korea. The colonoscopy findings of patients with sporadic duodenal adenomas were compared with those of age- and gender-matched healthy individuals who had undergone gastroduodenoscopies and colonoscopies during general screening examinations.
Between 2001 and 2008, 45 patients were diagnosed endoscopically with sporadic duodenal adenomas; 26 (58%) of these patients received colonoscopies. Colorectal neoplasia (42% vs 21%; odds ratio [OR], 2.8; 95% confidence interval [CI], 1.1 to 7.4) and advanced colorectal adenoma (19% vs 3%; OR, 9.0; 95% CI, 1.6 to 50.0) were significantly more common in patients with sporadic duodenal adenomas than in healthy control subjects.
Compared with healthy individuals, patients with sporadic duodenal adenomas were at a significantly higher risk for developing colorectal neoplasia. Such at-risk patients should undergo routine screening colonoscopies.
Duodenal neoplasms; Colorectal neoplasms; Colonoscopy; Endoscopy
Lymphangioma of the colon is a relatively rare non-epithelial tumor and usually presents as a submucosal polypoid lesion. Many cases incidentally discovered are usually asymptomatic. However, they may present as abdominal pain or bleeding, and their resection is normally required. Lymphangioma itself is generally recognized as a benign tumor and no cases of malignant transformation have yet been reported, although its natural history is currently unknown. To the best of our knowledge, this study is the first to describe a case of spontaneous resolution in multiple colonic lymphangiomas without any specific treatment.
Lymphangioma; Colon; Natural history
AIM: To evaluate duodenal polyps, divided into non-neoplastic and neoplastic lesions. In addition, the clinical characteristics of duodenal hyperplastic polyps are determined.
METHODS: We analyzed medical records of 50 114 consecutive patients submitted to for first diagnostic esophago-gastroduodenoscopy between January 2004 and December 2009. We excluded lesions on the ampulla of Vater and submucosal tumors. We studied 510 cases that were diagnosed endoscopically with duodenal polyps and enrolled a total of 221 cases that had undergone tissue biopsy. We analyzed the differences between non-neoplastic and neoplastic lesions, and determined the clinical features of duodenal hyperplastic polyps.
RESULTS: Non-neoplastic lesions were found in 196 patients and neoplastic lesions in 25 patients. On univariate analysis, there were significant differences in shape, location, and size. Polyps more than 10 mm in diameter or polyps in the second portion had independent risk factors for being neoplastic lesions, as identified by multivariate analysis. In 23 cases of hyperplastic polyps (79.3%), they were accompanied by gastro-duodenal pathology, which was possibly associated with Helicobacter pylori.
CONCLUSION: Polyps of more than 10 mm or polyps in the second portion of the duodenum should be evaluated by histological examination.
Duodenum; Polyp; Helicobacter pylori
Endoscopic resection has proven to be a safe and effective alternative to surgery for duodenal adenomas. However, few data are available on the adequacy of resection and long-term outcomes. This study evaluated the efficacy and longterm endoscopic findings in a cohort of Korean patients who underwent endoscopic mucosal resection (EMR) of sporadic duodenal adenomas.
Seventeen patients with nonampullary duodenal adenomas without familial polyposis syndrome and who were treated by EMR between January 2001 and December 2007 were evaluated retrospectively. Their management, follow-up, and outcomes were reviewed.
In total, seventeen lesions were removed from EMR in 17 patients (mean age, 59.3 years; 6 women, 11 men). The mean size of the tumors was 15.1 mm (median, 13 mm, range, 8-27 mm). Of these 17 adenomas, 16 adenomas were tubulous and 1 was tubulovillous. The EMR was performed successfully in all 17 patients in a single session. After a median follow-up period of 29 months (range, 13-72 months), all patients remained in remission. One patient had bleeding at the site of the EMR. There were no perforations after the EMR.
EMR for sporadic duodenal adenomas seemed to be a safe and effective treatment modality.
Duodenal neoplasm; Adenoma; Endoscopic mucosal resection; Treatment efficacy
AIM: To investigate whether percutaneous endoscopic gastrostomy (PEG) tube placement is safe in patients with ventriculoperitoneal (VP) shunts.
METHODS: This was a retrospective study of all patients undergoing PEG insertion at our institution between June 1999 and June 2006. Post-PEG complications were compared between two groups according to the presence or absence of VP shunts. VP shunt infection rates, the interval between PEG placement and VP shunt catheter insertion, and long-term follow-up were also investigated.
RESULTS: Fifty-five patients qualified for the study. Seven patients (12.7%) had pre-existing VP shunts. All patients received prophylactic antibiotics. The complication rate did not differ between VP shunt patients undergoing PEG (PEG/VP group) and non-VP shunt patients undergoing PEG (control group) [1 (14.3%) vs 6 (12.5%), P = 1.000]. All patients in the PEG/VP group had undergone VP shunt insertion prior to PEG placement. The mean interval between VP shunt insertion and PEG placement was 308.7 d (range, 65-831 d). The mean follow-up duration in the PEG/VP group was 6.4 mo (range, 1-15 mo). There were no VP shunt infections, although one patient in the PEG/VP group developed a minor peristomal infection during follow-up.
CONCLUSION: Complications following PEG placement in patients with VP shunts were infrequent in this study.
Percutaneous endoscopic gastrostomy; Ventriculoperitoneal shunt; Complication; Ventriculoperitoneal shunt infection; Prophylactic antibiotic
AIM: To evaluate the prevalence of chronic gastrointestinal symptoms and their impact on health-related quality of life (HRQOL) in the Korean population.
METHODS: A cross-sectional survey, using a reliable and valid Rome II based questionnaire, was performed on randomly selected residents, between 18 and 69 years in age. All respondents were interviewed at their homes or offices by a team of interviewers. The impact of chronic gastrointestinal symptoms on HRQOL was assessed using the Korean version of the 36-item Short-Form general health survey (SF-36).
RESULTS: Of the 1807 eligible subjects, 1417 (78.4%: male 762; female 655) were surveyed. Out of the respondents, 18.6% exhibited at least one chronic gastrointestinal symptom. The prevalence of gastroesophageal reflux disease (GERD), defined as heartburn and/or acid regurgitation experienced at least weekly, was 3.5% (95% CI, 2.6-4.5). The prevalence of uninvestigated dyspepsia, irritable bowel syndrome (IBS) and chronic constipation based on Rome II criteria were 11.7% (95% CI, 10.1-13.5), 2.2% (95% CI, 1.5-3.1), and 2.6% (95% CI, 1.8-3.5) respectively. Compared with subjects without chronic gastrointestinal symptoms (n = 1153), those with GERD (n = 50), uninvestigated dyspepsia (n = 166) and IBS (n = 31) had significantly worse scores on most domains of the SF-36 scales.
CONCLUSION: The prevalence of GERD, uninvestigated dyspepsia and IBS were 3.5%, 11.7% and 2.2% respectively, in the Korean population. The health-related quality of life was significantly impaired in subjects with GERD, uninvestigated dyspepsia and IBS in this community.
Chronic gastrointestinal symptom; Gastroesophageal reflux disease; Dyspepsia; Irritable bowel syndrome; Qaulity of life
AIM: To assess the occurrence of gastric acid reflux into the esophagus in endoscopically confirmed prolapse gastropathy syndrome (PGS).
METHODS: Using ambulatory esophageal pH measurement (BRAVOTM wireless esophageal pH monitoring system), twenty-six patients with PGS were compared with twenty-one patients with erosive esophagitis (EE) as controls. We assessed several reflux parameters, including the percentage of total time at pH < 4, and the DeMeester score.
RESULTS: There were no statistical differences between the PGS group and the EE group as to mean age, sex ratio and pH recording time. The EE group showed more severe reflux than the PGS group, as evaluated in terms of the longest duration of reflux, the number of reflux episodes, the number of reflux episodes lasting > 5 min, the total time with pH < 4 during acid reflux episodes, and the DeMeester score, but none of these parameters showed statistically significant difference. Although 53.8% (14/26) of the PGS group and 76.2% (16/21) of the EE group demonstrated pathologic acid reflux (DeMeester score > 14.72), there was no statistically significant difference between the two groups in the incidence of pathologic acid reflux (P = 0.11).
CONCLUSION: There was no statistically significant difference in pathologic acid reflux between the PGS and EE group. These data suggest that endoscopically diagnosed PGS might be a predictor of pathologic acid reflux.
Prolapse gastropathy syndrome; Pathologic acid reflux; Erosive esophagitis; Ambulatory esophageal pH monitoring; Retching
AIM: To determine whether thalidomide prevents microvascular injury in acute radiation proctitis in white rats.
METHODS: Fourteen female Wistar rats were used: six in the radiation group, six in the thalidomide group, and two in normal controls. The radiation and thalidomide groups were irradiated at the pelvic area using a single 30 Gy exposure. The thalidomide (150 mg/kg) was injected into the peritoneum for 7 d from the day of irradiation. All animals were sacrificed and the rectums were removed on day 8 after irradiation. The microvessels of resected specimens were immunohistochemically stained with thrombomodulin (TM), von Willebrand Factor (vWF), and vascular endothelial growth factor (VEGF).
RESULTS: The microscopic scores did not differ significantly between the radiation and thalidomide groups, but both were higher than in the control group. Expression of TM was significantly lower in the endothelial cells (EC) of the radiation group than in the control and thalidomide groups (P < 0.001). The number of capillaries expressing vWF in the EC was higher in the radiation group (15.3 ± 6.8) than in the control group (3.7 ± 1.7), and the number of capillaries expressing vWF was attenuated by thalidomide (10.8 ± 3.5, P < 0.001). The intensity of VEGF expression in capillaries was greater in the radiation group than in the control group and was also attenuated by thalidomide (P = 0.003).
CONCLUSION: The mechanisms of acute radiation-induced proctitis in the rats are related to endothelial cell injury of microvessel, which may be attenuated with thalidomide.
Radiation proctitis; Von Willebrand factor; Thrombomodulin; Vascular endothelial growth factor; Thalidomide