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C Ell

Publications and source records attributed to C Ell.

At least 19 recordsLinked to original sources
PubMed2006

Push-and-pull enteroscopy using the double-balloon technique/double-balloon enteroscopy.

Push-and-Pull enteroscopy/Double balloon enteroscopy (PPE/DBE) allows enteroscopy of the entire small bowel, or at least a substantial part of it. The complication rate is acceptably low. Severe complications such as pancreatitis and perforation were encountered in the literature in approximately 1% of all diagnostic PPE/DBEs. It can be expected that the complication rate of therapeutic PPE/DBEs is higher, comparable with the conventional endoscopy. The diagnostic yield is high, at approximately 75%, as is the therapeutic yield. The option of carrying out endoscopic therapy (in approximately 40%-50% of cases in the Western hemisphere) is an important aspect. Angiodysplasias are the main bleeding source, at least in Western countries. Using the PPE/DBE device, endoscopic treatments such as endoscopic hemostasis using injection and argon plasma coagulation, polypectomy, endoscopic resection, balloon dilation, and foreign-body extraction have become feasible even in the small intestine and can generally be performed safely and without relevant technical problems. Medical therapy can be started in up to 20% of cases-e.g., after a new or changed diagnosis of Crohn's disease. Surgical therapy is required in 10-20% of cases, due to malignant tumors or complex stenoses, for example. The main indication is mid-gastrointestinal bleeding.

Capsule Endoscopy↗
PubMed2006

Comparison of methylene blue-directed biopsies and four-quadrant biopsies in the detection of high-grade intraepithelial neoplasia and early cancer in Barrett's oesophagus.

BACKGROUND: Barrett's oesophagus embodies the risk of malignant transformation. High-grade intraepithelial neoplasia and early cancer in Barrett's oesophagus are often discrete or macroscopically occult lesions and show a patchy distribution and therefore, directed biopsies in combination with four-quadrant random biopsies are the gold standard for surveillance. AIMS: The aim of this prospective study was to compare methylene blue staining and random biopsies in patients with early Barrett's neoplasia. PATIENTS AND METHODS: Eighty-six patients (mean age 65+/-8 years) with histologically proven but macroscopically in evident high-grade intraepithelial neoplasia (n=17) or early cancer in Barrett's oesophagus (n=69) on HR-endoscopy with all together 98 lesions, were included. In the first step, four-quadrant random biopsies were taken during routine endoscopy (group I). In a second step, staining was performed with a 0.5% solution of methylene blue with a spray catheter. Biopsies of focal areas with decreased stain, heterogeneity of stain or absence stain were taken (group II). RESULTS: In 75/86 patients, high-grade intraepithelial neoplasia or early cancer in Barrett's oesophagus could be diagnosed in the methylene blue group while 56 patients were determined in the random biopsies group (P=0.053). High-grade intraepithelial neoplasia or early cancer was diagnosed in significantly more methylene blue-directed biopsies (80.9% versus 26.4%, P<0.005) and also significantly more lesions could be identified in the methylene blue group (96/98; 98%) while in the random biopsies group only 58/98 lesions (59%) could be localised (P<0.05). When methylene blue was used (1217 versus 562, P<0.0001), the average number of specimens taken with methylene blue per patient was about half of that with random biopsy (6.5 versus 14.1, P<0.0001). CONCLUSIONS: Chromoendoscopy with methylene blue diagnosed significantly more patients and lesions with intraepithelial neoplasia or early cancer in Barrett's oesophagus compared to random biopsies. In addition, significantly less biopsies were needed with methylene blue compared to random biopsies. The use of methylene blue-directed biopsies appears to improve the detection of intraepithelial neoplasia and early cancer in Barrett's oesophagus.

Adult↗
PubMed2006

Safety and efficacy of a new high power argon plasma coagulation system (hp-APC) in lesions of the upper gastrointestinal tract.

BACKGROUND: The aim of this study was to analyze safety and efficacy of a new high power argon plasma coagulation system in the upper gastrointestinal tract. METHODS: Data of 215 patients treated with a high power argon plasma coagulation system in the upper gastrointestinal tract 04/2003-01/2004, using a VIO APC device (VIO 300 D with APC 2; Erbe Elektromedizin, Tübingen, Germany; pulsed argon plasma coagulation, 20-120 W), were reviewed and analyzed. Indications were as follows: additive ablation therapy in curative treatment of early Barrett's cancer (122 patients); palliative treatment of oesophageal cancer (n=27); gastric adenoma/carcinoma (n=19); Zenker's diverticulum (n=8); and other. In 190/215 patients (149 males; mean age 67 years), the data were completely analyzable. Minor and major complications were evaluated. RESULTS: Minor complications (odynophagia, pain, fever) occurred in 24/277 sessions (8.7%); major complications (stenosis) in 3/277 sessions (1.1%) using at least 50 W. No perforation or bleeding occurred. The mean number of treatment sessions required was 1.46 (1-7); in the palliative treatment of oesophageal cancer, it was 2.5 (1-5). CONCLUSIONS: The high power argon plasma coagulation system was effective and safe in various gastrointestinal conditions. Due to it's high effectiveness and a low number of sessions required in tumour debulking, this high power argon plasma coagulation system might be used as an alternative to Nd:YAG laser.

Adult↗
PubMed2006

Push-and-pull enteroscopy using a single-balloon technique for difficult colonoscopy.

BACKGROUND AND STUDY AIMS: Several factors predict difficult or incomplete colonoscopy with a standard colonoscope, including female gender, low body mass index, extensive diverticulosis, and prior pelvic surgery. PATIENTS AND METHODS: A push-and-pull enteroscopy device and a single-balloon technique was used in 14 patients (six men, eight women; mean age 62 +/- 15 years) after failure of ileocolonoscopy or endoscopic therapy using either a standard or a pediatric colonoscope. The original ileocolonoscopy had been performed to investigate colon polyps (n = 6), an obscure inflammatory process in the ileocecal region (n = 6), or iron deficiency anemia with a positive fecal occult stool test (n = 2). RESULTS: Ileocolonoscopy was successfully performed using this push-and-pull technique in all 14 patients without technical problems or complications. All the endoscopic therapeutic interventions that were required were also performed without complications, with the exception of one instance of bleeding. Multiple polyps were found in six patients; a colon cancer was found in one patient; appendicitis combined with a carcinoid tumour of the appendix was diagnosed in one patient; ileocolitis was observed in two patients; one patient with Crohn's disease had stenoses in the region of an anastomosis; and in three patients no relevant pathological finding was seen. CONCLUSION: It was possible to perform ileocolonoscopy with therapeutic interventions using this new thin push-and-pull enteroscopy device with a single-balloon technique in patients who had previously undergone incomplete colonoscopy using a standard colonoscope.

Adult↗
PubMed2006

Secondary sclerosing cholangitis after long-term treatment in an intensive care unit: clinical presentation, endoscopic findings, treatment, and follow-up.

BACKGROUND AND STUDY AIMS: We present ten patients who developed secondary sclerosing cholangitis following long-term treatment in an intensive care unit (ICU) between 1999 and 2004. PATIENTS AND METHODS: Ten consecutive patients who had no evidence suggestive of pre-existing hepatobiliary disease were admitted to an ICU because of trauma (n = 5), intracerebral hemorrhage (n = 3), or nonabdominal postsurgical complications (n = 2). All the patients had required treatment with long-term ventilation, catecholamines, total parenteral nutrition, and several antimicrobial agents. RESULTS: Cholestasis was first noted within 11 days after the initial insult. Endoscopic retrograde cholangiopancreatography (ERCP), performed after a median follow-up of 69 days, revealed multifocal stricturing and beading of the intrahepatic bile ducts, and attenuation of the peripheral branches. In all the patients, the bile ducts were partially filled by black-pigmented thrombotic material. All the patients underwent endotherapy, which comprised sphincterotomy and removal of the occluding material, in an attempt to improve biliary drainage; the treatment had to be repeated in seven of the ten patients. After a median follow-up period of 21 months, despite transient clinical improvement following endotherapy, complete recovery has not been achieved in any of the patients and so far one patient has had to undergo orthotopic liver transplantation as a result of end-stage liver disease. CONCLUSIONS: The development of secondary sclerosing cholangitis in patients who have received long-term treatment in an ICU is a rare event of unknown pathophysiology, but patients demonstrate characteristic findings on ERCP. It is not known whether endotherapy can delay the progress of the condition in the long term.

Adult↗
PubMed2006

[Early duodenal adenocarcinoma arising in gastric metaplasia treated by endoscopic resection].

Early duodenal carcinoma is a rare entity. Most duodenal carcinomas are diagnosed at a more advanced stage. This report describes the case of a 59-year-old lady with an early duodenal adenocarcinoma diagnosed at check-up gastroduodenoscopy in an outpatient clinic who was referred to us for further investigation and management. The initial upper endoscopy at our department revealed a type IIa+c lesion in the proximal duodenum (10 - 12 mm diameter, flat elevated lesion with central depression). Using chromoendoscopy and magnification endoscopy the lesion could be well demarcated and neoplastic changes in the architecture of the intestinal villi could be detected. After submucosal epinephrine-saline injection, the lesion was removed by endoscopic resection without complications. Histopathological examination revealed the rare entity of an early duodenal carcinoma arising from incomplete-type gastric metaplasia in the duodenum. In summary, the presented paper describes a case of successful endoscopic treatment of an early duodenal carcinoma arising from incomplete gastric metaplasia.

Adenocarcinoma↗
PubMed2006

Endoscopic treatment of the "sump syndrome" after choledochoduodenostomy: a new technique using an amplatzer septal occluder.

A 58-year-old male patient had been suffering for 35 years from recurrent cholangitis, biliary sludge and infection-induced stone formation after open cholecystectomy because of empyema of the gallbladder and severe acute and delayed postoperative complications. The pathophysiological origin of this chronic "sump syndrome" was a choledochoduodenostomy which had been performed prophylactically at the time of the initial operation. The patient agreed to an experimental treatment option with use of an Amplatzer atrial-septal defect (ASD) occluder for closure of the symptomatic choledochoduodenal fistula. The double-disc occluder was introduced through a 9 French diameter and 90 cm long sheath side to side with a duodenoscope. Under endoscopic and fluoroscopic guidance the distal disc was opened in the common bile duct, then retracted against the fistula's orifice. Subsequently, the proximal disc was unfolded in the duodenum, while the 9 mm waist between the two discs filled and shut the fistula. No side effects or complications were detected. The day after the procedure, endoscopic evaluation demonstrated the correct position of the occluder and closure of the fistula. Over a period of 12 months, repeated assessments did not reveal any major problems. The patient felt a significant subjective improvement. The use of a self-expanding occluder system for closure of a choledochoduoenotomy complicated by chronic and symptomatic duodenocholedochal reflux might therefore represent an enrichment of the equipment of interventional endoscopists.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed2005

Push-and-pull enteroscopy using the double-balloon technique: method of assessing depth of insertion and training of the enteroscopy technique using the Erlangen Endo-Trainer.

BACKGROUND AND STUDY AIMS: This study was conducted to test a method of measuring the depth of insertion into the small bowel during push-and-pull enteroscopy using the Erlangen Endo-Trainer. Furthermore, the Erlangen Endo-Trainer model for training in the new method of push-and-pull enteroscopy using the double-balloon technique was also evaluated. MATERIALS AND METHODS: Specially prepared packages of porcine upper visceral organs were used, including the esophagus, stomach, duodenum, and small bowel, implanted into the Erlangen Endo-Trainer. In the first step of this study, all of the modifications needed to obtain a model useful for training in the new enteroscopy technique were tested, including different lengths of small bowel. In the next step, the Erlangen Endo-Trainer was used to evaluate a special method of measuring the depth of insertion during push-and-pull enteroscopy by comparing estimated insertion depths of 100 cm and 200 cm, marked on the porcine small bowel, with endoscopic insertion depths determined afterwards by measuring the length of the small bowel from the pylorus to the mark on the porcine small bowel. Additionally, the Endotrainer was used to demonstrate the principle of double-balloon enteroscopy and to provide training in this new enteroscopy technique with a lifelike simulation. RESULTS: The modified Erlangen Endo-Trainer proved its value for demonstrating the principle of push-and-pull enteroscopy and for providing training in this enteroscopic technique as well as for testing the measurement method. The evaluation of the measurement method showed that the estimation of the insertion depths was accurate, with a mean deviation of less than 10 %. A total of 13 workshops (seven national and six international), including a total of 97 participants, were carried out between January and August 2004. Under the supervision of one of the authors, pairs of trainees were able to reach the ileal valve or the end of the small bowel from the oral route. CONCLUSIONS: The modified Erlangen Endo-Trainer is useful for training in the push-and-pull enteroscopy technique. The new specially developed method of measuring the depth of insertion during push-and-pull enteroscopy seems to be valid.

Animals↗
PubMed2005

Extraction of entrapped capsules from the small bowel by means of push-and-pull enteroscopy with the double-balloon technique.

The new technique of push-and-pull enteroscopy using the double-balloon technique (double-balloon enteroscopy) makes it possible to remove swallowed foreign bodies causing intestinal obstruction deep in the small bowel without the need for surgical laparotomy. This report describes two cases of enteroscopic removal of entrapped capsules. In one patient with acute recurrent intestinal bleeding and recurrent abdominal pain, Crohn's disease had been suspected on capsule endoscopy. The second patient, with known Crohn's disease, was suffering from abdominal pain and underwent capsule endoscopy for investigation of the small bowel. Prior enteroclysis had not revealed stenoses in either patient. An oral approach was chosen and the capsules were identified approximately 140 cm and 310 cm from the pylorus, respectively, in front of stenoses. The capsule endoscopes were removed successfully in both patients by means of push-and-pull enteroscopy using a new enteroscope device.

Device Removal↗
PubMed2005

Push-and-pull enteroscopy in the small bowel using the double-balloon technique: results of a prospective European multicenter study.

BACKGROUND AND STUDY AIMS: The aim of this study was to evaluate the feasibility, safety, and clinical impact of push-and-pull enteroscopy (PPE) in patients with suspected or documented small-bowel diseases, in a prospective multicenter trial in three European medical centers. PATIENTS AND METHODS: A total of 100 patients (mean age 56 +/- 16 years; range 13 - 90) were included at the three institutions between July and November 2004. The leading symptoms were: acute recurrent or chronic gastrointestinal bleeding (n = 64), polyposis syndrome (n = 8), chronic abdominal pain (n = 7), chronic diarrhea (n = 7), and others (n = 14). RESULTS: No major PPE-associated complications such as perforation, bleeding, or relevant injury to the small-bowel tissue or mesentery were encountered. Minor complications occurred in 12 %. The mean time required to carry out the procedure from the oral and anal approaches was 75 +/- 19 min (32 - 150 min). The average insertion depths into the small bowel were 200 +/- 70 cm per PPE session (220 +/- 90 cm with the oral approach and 130 +/- 80 cm with the anal approach). The average radiation exposure (including diagnostic and therapeutic interventions) was 2.1 +/- 2.4 min and 155 +/- 159 dGy/cm2. PPE was fully diagnostic in 72 % of cases. The majority of the patients (34 %) were suffering from angiodysplasias; ulcerations and erosions of various etiologies were seen in 16 %, and polyps and tumors in 13 %. The PPE findings played a role in the subsequent treatment in 62 % of the patients. Endoscopic treatments, including argon plasma coagulation, polypectomy, dilation, and foreign-body extraction, were carried out in 42 %. Medical treatment was given in 12 %, and patients were referred for surgery in 8 % of cases. CONCLUSIONS: This prospective analysis shows that PPE is safe and has a high diagnostic and therapeutic yield in patients with suspected or known small-bowel disease.

Adolescent↗
PubMed2005

Early-stage small-bowel adenocarcinoma: a review of local endoscopic therapy.

Early adenocarcinomas in the small intestine are a rare entity. Most adenocarcinomas in the small intestine are diagnosed at a more advanced stage. After surgical resection, only 3 - 10 % are found in stage T1 and 0 - 3 % in stage Tis (high-grade intraepithelial neoplasia), resulting in an overall 3 - 13 % rate of early-stage small-intestinal adenocarcinomas. The diagnosis of early small-intestinal carcinoma by endoscopy is still very rare, although it will probably improve with the development of new endoscopic techniques. At present there have been only two studies and a few case reports on the treatment of early duodenal carcinoma by endoscopic resection. No major complications such as massive bleeding or perforation occurred in the studies and case reports, which show that endoscopic resection is a safe and effective treatment for early duodenal cancers that have not invaded the submucosa. Endoscopic resection can be carried out with reduced costs and lower morbidity and mortality rates in comparison with surgery.

Adenocarcinoma↗
PubMed2005

Successful endoscopic resection of an esophageal metastasis from a preceding squamous-cell tonsillar carcinoma.

This report describes the case of a 62-year-old man with tonsillar carcinoma who had undergone esophagectomy due to an esophageal metastasis. Subsequently, a second metastasis occurred in the residual esophagus, and he presented for evaluation for local endoscopic therapy. The initial upper endoscopy revealed a type IIa - c lesion at 21 cm from the incisors, within a segment suspicious for Barrett's mucosa. As part of the complex treatment approach in this patient, endoscopic resection of the lesion was carried out using the suck-and-cut technique with ligation. Histology showed that the lesion was a metastasis from a squamous-cell carcinoma, with focal infiltration of the upper submucosal layer and vascular invasion consistent with the hypothesis of hematogenous spread from the preceding tonsillar carcinoma. The resection margins were tumor-free. At the time of writing, the patient had been recurrence-free for more than 9 months. In summary, the present paper describes a unique case of successful endoscopic resection of an esophageal metastasis associated with an antecedent tonsillar carcinoma.

Carcinoma, Squamous Cell↗
PubMed2005

Curative treatment for high-grade intraepithelial neoplasia in Barrett's esophagus.

BACKGROUND AND STUDY AIMS: The incidence of premalignant and malignant lesions in specialized intestinal metaplasia of the esophagus has increased dramatically in the industrialized world in recent years. This report evaluates the efficacy and safety of local endoscopic therapy for high-grade intraepithelial neoplasia (HGIN) in Barrett's esophagus. PATIENTS AND METHODS: Over a 5-year period between October 1996 and September 2001, a total of 379 patients were referred with a suspicion of early Barrett's cancer. In a prospective study, 44 patients with HGIN in Barrett's esophagus were selected for local endoscopic treatment. Endoscopic resection was carried out in 14 patients in whom the HGIN was re-detectable, and 27 patients in whom the HGIN was not re-detectable underwent photodynamic therapy (PDT). Endoscopic resection and PDT were combined in three patients. RESULTS: Complete remission was achieved in 43 of the 44 patients (97.7 %). No major complications occurred. A mean of 1 session was needed to achieve complete local remission. During a mean follow-up period of 36 months (range 7 - 61 months), recurrent or metachronous lesions were observed in six patients (17.1 %), all of whom received a second successful endoscopic treatment. CONCLUSIONS: Endoscopic therapy is a safe alternative treatment regimen for HGIN in Barrett's esophagus, providing a middle way between the widely promulgated options of a "watch-and-wait" policy and radical esophagectomy.

Adult↗
PubMed2005

Capsule endoscopy in gastrointestinal lymphomas.

BACKGROUND AND STUDY AIMS: Capsule endoscopy (CE) is a new procedure for small-bowel imaging. The potential contribution of this method to the diagnosis and staging of gastrointestinal lymphomas has not yet been evaluated. The aim of this prospective study was to assess the frequency and morphology of different forms of intestinal pathology in patients with gastrointestinal lymphomas. PATIENTS AND METHODS: Commercially available capsule video endoscopes were administered to 27 patients (16 men and 11 women, aged 27-77) with known gastrointestinal lymphomas. CE was also carried out in 30 control individuals. RESULTS: All seven patients with primary intestinal lymphomas who were examined were found to have pathological findings on CE--four with ulcerations, four with nodes, three with villous atrophy, and one with plaques/white villi. One patient with severe diarrhea was examined three times before and after chemotherapy, and improvement of the lesions was evident, as well as resolution of diarrhea. Twenty patients with gastric lymphoma were examined (16 with low-grade and four with high-grade B cell lymphomas). The capsule did not leave the stomach in three patients, suggesting impaired motility. The small-bowel transit times were 261+/-41 min for intestinal lymphoma, 245+/-62 min for gastric lymphoma, and 224+/-82 min for controls (P>0.05). Five of the 20 patients with gastric lymphoma had pathological findings in the intestine--three with plaques/white villi, two with nodes, and two with villous atrophy. In two patients, subsequent biopsies revealed secondary follicular lymphoma and high-grade lymphoma, respectively. CONCLUSIONS: CE is a valuable diagnostic tool for defining the extent of bowel involvement and assessing the efficacy of treatment in patients with gastrointestinal lymphoma.

Adult↗
PubMed2004

Vacuum Rabi splitting with a single quantum dot in a photonic crystal nanocavity.

Cavity quantum electrodynamics (QED) systems allow the study of a variety of fundamental quantum-optics phenomena, such as entanglement, quantum decoherence and the quantum-classical boundary. Such systems also provide test beds for quantum information science. Nearly all strongly coupled cavity QED experiments have used a single atom in a high-quality-factor (high-Q) cavity. Here we report the experimental realization of a strongly coupled system in the solid state: a single quantum dot embedded in the spacer of a nanocavity, showing vacuum-field Rabi splitting exceeding the decoherence linewidths of both the nanocavity and the quantum dot. This requires a small-volume cavity and an atomic-like two-level system. The photonic crystal slab nanocavity--which traps photons when a defect is introduced inside the two-dimensional photonic bandgap by leaving out one or more holes--has both high Q and small modal volume V, as required for strong light-matter interactions. The quantum dot has two discrete energy levels with a transition dipole moment much larger than that of an atom, and it is fixed in the nanocavity during growth.

Journal Article↗
PubMed2004

Entanglement between a photon and a quantum well.

The lack of translational invariance perpendicular to the plane of a single quantum well causes equal probability for spontaneous emission to the left or right. Combining one emission path from the left and one from the right into a common detector leads to interference fringes for fundamentally indistinguishable paths corresponding to geometries where the same in-plane momentum is transferred to the quantum well. For all other paths, no interference is observed because of the entanglement between the photon and extended Bloch states of the many-body system. In multiple-quantum-well structures the interference can be controlled via the spacing between the wells.

Journal Article↗