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Biomedical subjects

C Ell

Publications and source records attributed to C Ell.

At least 55 records · Page 3Linked to original sources
PubMed2000

Photodynamic therapy of gastric cancer.

Photodynamic therapy is a fascinating concept that will continue to occupy many research groups around the world in coming years. Although a widespread clinical application for the method has not yet emerged, there are good prospects that photodynamic therapy will establish itself at major gastroenterologic centers as an endoscopic procedure with few or no side effects in the treatment of Barrett's esophagus (sever dysplasia and early carcinoma) and, in selected cases, for the treatment of early gastric carcinoma.

Drug Administration Routes↗
PubMed1999

Photodynamic destruction of high grade dysplasia and early carcinoma of the esophagus after the oral administration of 5-aminolevulinic acid.

BACKGROUND: Photodynamic therapy (PDT) is a new local, endoscopically controlled therapeutic concept based on the selective sensitization of malignant and precancerous lesions prior to light-induced tissue destruction. 5-aminolevulinic acid (5-ALA) appears to be a promising alternative photosensitizer with a high mucosa specificity without phototoxic side effects on the skin. The authors report on their experiences with this new form of PDT in 27 patients. METHODS: Twenty-seven patients (6 females and 21 males; ages 47-79 years) with histologically proven high grade dysplasia (n = 9) and early carcinoma (normal endoultrasonography or classified as uT1N0M0; n = 19; 1 patient had 2 lesions) of the esophagus were included in this study. Approximately 4-6 hours after oral ingestion of 5-ALA in a dosage of 60 mg/kg of body weight, laser light irradiation was conducted with a dye laser system with a wavelength of 635 nanometers at a light dose of 150 J/cm(2). RESULTS: The length of the segment of the esophagus with severe dysplasia or carcinoma of the mucosa varied between 0.5-9.0 cm (mean length, 2.5 cm). High grade dysplasia was eradicated in all patients. In addition, 19 mucosal tumors in 18 patients were treated successfully in 10 of 19 cases with an average of 1.7 treatment sessions and a mean follow-up of 16.9 months (range, 3-37 months). Method-related morbidity and mortality were not observed. CONCLUSIONS: Severe dysplasia and superficial (</=2 mm) mucosal carcinoma of the esophagus can be ablated completely by 5-ALA-PDT. PDT with 5-ALA has few side effects and might offer an alternative to esophagectomy or radiochemotherapy.

Aged↗
PubMed1999

Extraction of migrated self-expanding esophageal metal stents.

BACKGROUND: When self-expanding metal stents are used in the palliative treatment of malignant stenoses complications can occur and require the endoscopic extraction of the stent. METHODS: Three Gianturco-Z stents and two EsophaCoil stents had to be extracted because of migration (4 patients) and strangulation of healthy esophageal tissue between the coil loops during EsophaCoil stent release (1 patient). Because of the strong expansion force of the Gianturco-Z stent, the plastic sheath of a polypectomy snare was replaced by the steel sheath of a basket used for mechanical lithotripsy of bile duct stones. The sufficient resistance of the steel sheath allowed the stents to be compressed. The EsophaCoil stents were gradually retracted with a polypectomy snare over a plastic tube. RESULTS: All stents could be extracted successfully. There were no severe complications related to extraction. CONCLUSION: By means of the endoscopic extraction techniques described above, it is possible to safely remove self-expanding esophageal stents.

Aged↗
PubMed1999

KTP laser destruction of dysplasia and early cancer in columnar-lined Barrett's esophagus.

BACKGROUND: The rising incidence of esophageal adenocarcinoma in western countries requires a new strategy in the management of dysplasia in Barrett's esophagus. Esophagectomy, which has high morbidity and mortality rates, has been recommended to treat patients with severe dysplasia. Strictly superficial laser coagulation with tissue ablation therefore is a desirable option for the management of dysplasia in Barrett's esophagus because the tissue to be ablated is only about 2 mm thick. Potassium-titanyl-phosphate (KTP) laser light with a wavelength of 532 nm is preferentially absorbed by hemoglobin and therefore combines excellent coagulation with limited tissue penetration. We report first clinical results with KTP laser superficial vaporization of dysplasia and early cancer in Barrett's esophagus. METHODS: Eight men and 2 women 43 to 84 years of age with short segments of Barrett's esophagus or traditional Barrett's esophagus and histologically proved low-grade (n = 4) and high-grade (n = 4) dysplasia or early adenocarcinoma (n = 2) were selected for this pilot study. For all patients thermal endoscopic destruction was conducted with a frequency-doubled neodymium:yttrium-aluminum-garnet (Nd:YAG) KTP laser system. Laser therapy was performed by means of the free-beam method with coaxial insufflation of gas. An average of 2.4 sessions per patient were required for ablation of the Barrett's mucosa. RESULTS: Two to three days after laser treatment the response of the ablated mucosa was assessed with endoscopy and biopsy. Samples taken showed fibrinoid necrosis of the mucosal layer. A complete response was obtained for all 10 patients. Replacement by normal squamous cell epithelium was induced in combination with acid suppression therapy of up to 80 mg omeprazole daily. No complications occurred. In two patients biopsy showed specialized mucosa beneath the restored squamous cell epithelial layer. Follow-up times were as long as 15 months (mean value 10.6 months). CONCLUSIONS: KTP laser destruction of Barrett's esophagus induced mucosal regeneration with normal squamous cell epithelium in combination with acid suppression. Limitation of the depth of thermal destruction in Barrett's esophagus minimizes risk for perforation or stricture formation. KTP laser ablation of Barrett's esophagus seems to be feasible and safe in short segments of Barrett's esophagus with dysplasia or early cancer.

Adenocarcinoma↗
PubMed1999

Impact of skill and experience of the endoscopist on the outcome of endoscopic sphincterotomy techniques.

BACKGROUND: Our aim was to assess the influence of the skill and experience of the endoscopist on the success and risk of endoscopic sphincterotomy techniques. METHODS: The outcome of all endoscopic sphincterotomies (n = 1335) carried out between 1988 and 1995 were retrospectively analyzed with respect to the endoscopist performing the procedure. Endoscopists were differentiated according to whether they had previous experience with endoscopic sphincterotomy techniques (n > 100) and the frequency of endoscopic sphincterotomy during the study period (>40, 26 to 40, 10 to 25, <10 per year). RESULTS: Indications for endoscopic sphincterotomy techniques and technical execution had only a minor influence on the results of endoscopic sphincterotomy and were comparable for the individual endoscopists. The overall success rate of endoscopic sphincterotomy was 94.4% and did not significantly differ among the endoscopists. The overall complication rate of endoscopic sphincterotomy was 7.3%. Endoscopists learning endoscopic sphincterotomy techniques with a case frequency of less than 10 procedures per year had a consistently high complication rate (10.5%). Those learning endoscopic sphincterotomy techniques with a case frequency of more than 25 procedures per year had an above-average complication rate for their first 40 endoscopic sphincterotomy procedures and a significant decrease in complication rate as the number of procedures increased. The complication rate for experienced endoscopists was 7.7%. There were distinct and, in one case, significant differences in complication rates between individual endoscopists (11.5% vs. 4.8%, p = 0.01). However, when corrected for multiple testing, there were no significant differences at the p < 0. 05 level. The endoscopic sphincterotomy frequency of the endoscopist was the only significant risk factor for complications. Endoscopists with a frequency of more than 40 procedures per year had a significantly lower complication rate (5.6%) than endoscopists with a lower case frequency (9.3%, p < 0.05). CONCLUSIONS: A low endoscopic sphincterotomy frequency is, even for endoscopists with previous experience with the procedure, a risk factor for complications after endoscopic sphincterotomy. The learning of endoscopic sphincterotomy techniques requires a minimum of 40 procedures, but also after 100 procedures a further decrease of the complication rate can be expected.

Adult↗
PubMed1999

Antibiotic prophylaxis in percutaneous endoscopic gastrostomy (PEG): a prospective randomized clinical trial.

BACKGROUND AND STUDY AIMS: The most frequent complication reported for percutaneous endoscopic gastrostomy (PEG) is peristomal wound infection which occurs in as many as 30 % of patients. In the studies published so far, the question of whether antibiotic prophylaxis reduces the incidence of peristomal wound infection has remained controversial. We therefore conducted a prospective, randomized trial to determine whether antibiotic prophylaxis can reduce the incidence of peristomal wound infection associated with PEG. PATIENTS AND METHODS: During a 2-year-period a total of 347 patients (251 men, 96 women; mean age 60.2+/-5) were included in our study. In all cases, a 9-French gauge Freka gastrostomy tube was inserted using the "pull" technique. The patients were randomly assigned to three different treatment groups (group 1, antibiotic prophylaxis with 2 g cefotaxime; group 2, antibiotic prophylaxis with 4g piperacillin plus 0.5g tazobactam; group 3, no antibiotic prophylaxis). For a period of one week after gastrostomy, the peristomal area was evaluated using a wound score. According to the score, peristomal infections were classified as being of degree I-IV. Infections of up to degree III were regarded as minor, while an infection of degree IV was defined as a severe complication. RESULTS: PEG tubes were successfully placed in 336/347 patients (97 %). Of the 336 patients, 29 were excluded because of incomplete follow up (dropout rate 9%). Cases included were: in group 1, n = 101; in group 2, n = 100, and in group 3, n = 106. There was no mortality related to PEG insertion. There were five instances of severe complications (1.6%). Patients who received antibiotic prophylaxis had mean daily combined wound scores that were significantly lower than those of patients without antibiotic prophylaxis (P < 0.01). The control group (no antibiotic prophylaxis) exhibited significantly more peristomal wound infections of degree III (n = 8) than antibiotic prophylaxis group 1 (n = 0, P < 0.001) or antibiotic prophylaxis group 2 (n = 1, P < 0.012). Three patients in group 3 (no antibiotic prophylaxis) and one patient in group 2 developed peritonitis. CONCLUSIONS: Severe wound infections requiring medical or endoscopic intervention are very rare events after PEG insertion. Antibiotic prophylaxis significantly reduces the risk of peristomal wound infection associated with PEG insertion. Antibiotic prophylaxis, therefore, is to be recommended as a general measure in percutaneous endoscopic gastrostomy.

Antibiotic Prophylaxis↗
PubMed1999

A new long-range through-the-scope balloon applicator for photodynamic therapy in the esophagus and cardia.

BACKGROUND AND STUDY AIMS: Photodynamic therapy (PDT) is a new local, endoscopically controlled therapeutic technique based on the sensitization of malignant and precancerous lesions prior to light-induced tissue destruction. PDT of Barrett's esophagus with severe dysplasia, or of mucosal carcinomas and superficial squamous-cell cancer of the esophagus, requires light application devices allowing homogeneous illumination of the tissue surface in spite of esophageal motility and respiratory movement. On the basis of a commercially available through-the-scope balloon system, we developed a long-range light applicator for homogeneous and circumferential irradiation during PDT, and describe here the initial clinical experience with the device. PATIENTS AND METHODS: The new balloon applicator consists of a flexible cylindrical diffuser fiber with a length of up to 10 cm, depending on the lesion to be illuminated, and an inflatable balloon based on the type of balloon used for esophageal dilation. The balloon is made of a transparent polyurethane membrane with negligible absorption (<5%) at lambda = 600-700 nm, and it can be positioned through the biopsy channel of a conventional endoscope, with direct endoscopic visualization of the targeted lesion. The light intensity distribution perpendicular to the optical axes of the diffuser was measured for red laser light (lambda = 632.8 nm) and for green laser light (lambda = 542 nm). The study of photodynamic treatment included two women and four men (aged 48-79 years) with histologically proved high-grade dysplasia (n = 2) or mucosal cancer in Barrett's esophagus (n = 2) and superficial squamous-cell cancer (SCC) (n = 2), who had undergone EUS staging showing uT0 or uT1N0. Laser light irradiation was conducted after oral ingestion of 5-aminolevulinic acid (5-ALA) or intravenous administration of meta-(tetrahydroxyphenyl)chlorin (mTHPC). RESULTS: Both in vitro and in vivo, precise positioning of the new application system at the targeted tissue and homogeneous illumination were feasible, safe and effective. The total efficiency of transmitted light at wavelengths of lambda = 632.8 nm and lambda = 542 nm was 85-90%. A high degree of homogeneity was measured with applicator lengths of between 15 mm and 95 mm, and the maximum deviation from the mean intensity extended over a range of 40% over the total length of 80 mm. High-grade dysplasia was eradicated in all patients, and in addition mucosal cancer was successfully destroyed in three-quarters of them, requiring an average of 1.3 treatment sessions, with a mean follow-up of 12 months (range 10-15 months). CONCLUSIONS: This centering balloon system may in the future be capable of improving light application techniques during esophageal photodynamic therapy, making PDT a more reliable alternative modality for minimally invasive treatment of high-grade dysplasia and early Barrett's esophagus or squamous-cell carcinoma, as compared with esophagectomy.

Adenocarcinoma↗
PubMed1999

Local treatment of early cancer in short Barrett's esophagus by means of argon plasma coagulation: initial experience.

In recent years endoscopically controlled local therapeutic methods, such as photodynamic therapy, mucosectomy, or laser therapy, have been used with a curative aim for the destruction of early esophageal or gastric cancers. We report on our experience of treating histologically proven mucosal cancer in Barrett's esophagus with argon plasma coagulation (APC), in three patients. All the mucosal esophageal cancers, with a mean diameter of 4 mm, were successfully destroyed after one or two treatment sessions. Additionally, in two of the three patients the specialized columnar epithelium was replaced by normal squamous cell epithelium when APC treatment was combined with omeprazole. In the third patient with Barrett's esophagus, a partial squamous cell re-epithelialization was induced. No method-related mortality and morbidity were observed. During the mean follow-up of 24.3 +/- 1.1 months (range 23-25 months) one tumor recurrence developed which was successfully treated with photodynamic therapy. In patients with small early Barrett's carcinoma APC might offer an effective, minimally invasive alternative to mucosectomy or photodynamic therapy, as the treatment procedure is less cumbersome and the equipment less expensive.

Adenocarcinoma↗
PubMed1999

Esophageal achalasia: intrasphincteric injection of botulinum toxin A versus balloon dilation.

BACKGROUND AND STUDY AIMS: In patients with esophageal achalasia, pneumatic dilation is the treatment of choice, but it bears the risk of perforation in about 4% of cases. A new nonsurgical method, intrasphincteric injection of botulinum toxin A, has shown promising initial results, and we thus undertook this study to compare the long-term outcome of these two methods. PATIENTS AND METHODS: In a prospective randomized study, 24 patients with definitive esophageal achalasia were divided into two equal groups and underwent either balloon dilation or injection of botulinum toxin (20 U injected into each of the four quadrants in the lower esophageal sphincter). The outcome was assessed on the basis of a symptom score documented before treatment and at regular intervals for two and a half years thereafter. Complications associated with the two techniques were also documented. RESULTS: No relevant complication occurred in either of the treatment groups. Initially, dilation was successful in 10 of 12 patients (83%), and botulinum toxin injection in 9 of 12 patients (75%). The symptom scores showed no significant differences between the two groups before and one month after treatment. Over the two and a half year follow-up, however, all nine successfully treated patients in the botulinum toxin group experienced recurrence of symptoms, but only four of the ten patients (40%) in the dilation group. CONCLUSIONS: The two treatment methods initially had equal success rates, but in the long term the effect of the botulinum toxin injection was statistically significantly shorter than that of balloon dilation. As fewer risks are associated with the injection treatment, studies should be undertaken either to identify patient subgroups in whom botulinum toxin can be effective long-term or to test substances with longer-lasting effects.

Adolescent↗
PubMed1999

Gastric involvement in progressive systemic sclerosis: electrogastrographic and sonographic findings.

OBJECTIVE: To determine whether electrogastrography (EGG) can discern sonographically demonstrated motility disorders in patients with progressive systemic sclerosis (SSc) and to evaluate EGG as a possible diagnostic tool. DESIGN: Prospective study with control group and testing for reliability. SUBJECTS: 15 SSc patients [women aged 33-70 years (mean 53.3 years)] and 15 healthy volunteers. METHODS: Bipolar cutaneous EGG was recorded to obtain the following parameters: period dominant frequency (PDF), percentage of gastric dysrhythmia and normogastria (defined as 2-4/min), period dominant power (PDP) and its change after a standardized meal of 500 kcal (2093 kJ), and instability coefficients of dominant frequency and power (DFIC, DPIC). Simultaneously, real-time sonography was performed in the aortomesenteric plane (3.5-MHz curved-array probe). In 10 patients and 13 control subjects, the distance from the anterior wall of the gastric antrum to the abdominal skin was measured. RESULTS: Three patients (20%) showed hypomotility of the gastric antrum sonographically. The percentage of bradygastria was significantly lower in these patients, but the PDF, DFIC and DPIC values were not significantly different. The distance between the cutaneous electrodes and the antrum bore a greater relationship to the PDP values than did the sonographically demonstrated number of gastric contractions. CONCLUSIONS: Although cutaneous EGG can be performed in SSc patients without apparent derangement in frequency and stability of the signal, it offers no advantage over sonography in diagnosis and follow-up.

Adult↗
PubMed1999

[Endoscopic therapy of Barrett esophagus--a supplement to drug and surgical options?].

Within the last few years intestinal metaplasia at the gastroesophageal junction (Barrett's esophagus) has turned out to be a "shooting star" in the field of gastrointestinal diseases. The detection rate of Barrett's epithelium by the endoscopists and pathologists has raised dramatically as well as the incidence of the carcinoma at the gastroesophageal junction. Furthermore the "short Barrett" was discovered as a relevant risk factor for cancer development. To date ablation techniques with thermal devices, photodynamic techniques (PDT) and the mucosal resection (EMR) compete as local endoscopic treatment methods. However to date it is still in discussion whether in case of nondysplastic Barrett's esophagus endoscopic therapy is an "overtreatment" and an "undertreatment" in case of Barrett's with high-grade dysplasia or early cancer. The currently available data are discussed.

Barrett Esophagus↗
PubMed1999

[Optimized extracorporeal shockwave lithotripsy of gallbladder calculi: a prospective randomized therapy comparison].

UNLABELLED: Is "pulverization" or "fragmentation" the best endpoint of extracorporeal shock wave application in ESWL of gallbladder stones? Has gallbladder motility a potential for the prevention of stone recurrence? METHODS: Prospective, monocentric study with randomization between the conventional treatment strategy (endpoint of shock wave application: fragments < or = 4 mm, concomitant oral chemolitholysis) and an intensified treatment strategy (endpoint of shock wave application: Pulverization, no chemolitholysis). Prevention of stone recurrence: At least once per month for one hour after a meal standardized position (back position, lowered chest). RESULTS: 34 patients, age 46 +/- 14 years (27 women, seven men) were included (F-ESWL: n = 18; P-ESWL: n = 16). Gallbladder motility, number, size and CT-measured calcifications of stones were comparable for both groups. P-ESWL patients received more shock wave pulses than F-ESWL patients and more treatment sessions. P-ESWL resulted in a better fragmentation and pulverization of stones was reached significantly more often (p < 0.05). The time period for stone clearance was significantly depending on the fragmentation result (pulverization: 0.7 months vs. fragments < or = 4 mm: 6.6 months vs. fragments > or = 4 mm: 8.0 months; p < 0.01). The stone free rate after twelve months was 87.5% for P-ESWL and 72.2% for F-ESWL (n.s.) and correlated significantly with the fragmentation result (p < 0.01). Pain sensations during stone clearance were significantly reduced by P-ESWL. Stonefree patients were followed up for 30 +/- 13 months, the total recurrence rate was 7.1%. CONCLUSIONS: Aiming for pulverization of gallbladder stones by means of intensified extracorporeal shock wave application is at least equal or in tendency superior compared to disintegration to fragements < or = 4 mm. Gallbladder motility might be useful to prevent gallstone recurrence after successful ESWL.

Adult↗
PubMed1998

[Cholestasis: interventional therapy].

Treatment of cholestasis by bile duct obstruction is nowadays dominated by endoscopy and other interventional measures. Intraductal concrements can be removed almost always without open surgery. This is as a rule achieved by a transpapillary approach with the additional use of lithothripsy. Percutaneous transhepatic treatment of concrements is restricted to patients in which a transpapillary approach is impossible. Stenoses of biliary ducts by malignancies are treated with plastic or metallic endoprosthesis if curative resection is precluded. Percutaneous drainage is a valid option in reserve. Stenosis of the papilla by scars, tumors or sphincter dysfunction are mainly treated endoscopically, malignancies--if possible--by radical surgery. Rare causes for obstruction have also to be considered. They are in most instances amenable to interventional procedures.

Bile Duct Neoplasms↗
PubMed1998

[Long-term results of extracorporeal peizoelectric shock wave lithotripsy of parotid stones].

OBJECTIVE: To evaluate prospectively the recently developed method of extracorporeal shock-wave treatment of stones of the parotid gland. PATIENTS AND METHODS: 76 patients with symptomatic, sonographically proven, solitary stones of the parotid gland (36 females, 40 males; aged 2-80 years) were treated with extracorporeal piezoelectric shock-wave lithotripsy (ESWL) after failed conservative management (sialagogues, gland massage, duct bougie dilation). RESULTS: Parotid stones were no longer demonstrable after a mean follow-up time of 48 (6-71) months in 38 of the 76 patients; they were symptom-free and no new stones had formed. A residual, but symptom-free, stone was found in another 20 patients (26%) of whom 13 (17%) reported marked improvement after ESWL. No change from pretreatment symptoms occurred in five patients (7%) so that operative removal had to be performed. The success rate of the lithotripsy was independent of size and site of the stone. CONCLUSION: ESWL is the method of first choice in the treatment of parotid gland stones after unsuccessful conservative treatment and obviates operative gland removal in most cases.

Adolescent↗
PubMed1998

[Diagnostic procedure in cholecystolithiasis. Diagnostic approach, repeat examinations and (incidental) findings].

If non-surgical methods are to be taken into account in the therapeutic decision-making process in cholecystolithiasis, an expanded diagnostic work-up including not only stone parameters but also gallbladder function, is needed. In 2270 patients (1649 women, 621 men; age: 47.2 +/- 14 years) with (suspected) "cholecystolithiasis" attending the special gallstone outpatient clinic at a university medical department within a period of 5 years the diagnostic procedures most commonly used in both the doctor's office and hospital were abdominal ultrasonography (52%/78%), laboratory investigations (28%/39%) and plain films of the biliary tract (27%/39%). In the doctor's office gallbladder function testing took the form of an cholecystogram (17% of the patients); in the hospital ultrasonography to determine gallbladder contractility (38%). With decreasing frequency, the following additional procedures were carried out (office/hospital): CT 3%/19%, esophagogastroduodenoscopy 7%/3%, intravenous cholegram 6%/0.6%, abdominal X-ray 1%/0.4%, ERCP 1%/0.4%, chest X-ray 0.8%/1.6%. Duplicated examinations showed a relevant frequency only for ultrasonography (39% of the cases), laboratory investigations (18%) and plain films of the gallbladder (4%). Pathologic secondary findings were established in 22% of the cases.

Adolescent↗