Prevalent esophageal body motility disorders underlie aggravation of GERD symptoms in morbidly obese patients following adjustable gastric banding.

HYPOTHESIS: Preexisting gastroesophageal reflux disease (GERD) and esophageal motility disorders may affect the outcome of laparoscopic adjustable gastric banding (AGB). DESIGN: Prospective cohort study. SETTING: Tertiary referral center. PATIENTS: Between January 1, 1996, and December 31, 2002, AGB procedures were performed in 587 patients (mean body mass index, 46.7 [calculated as weight in kilograms divided by the square of height in meters]). The study population was composed of patients with preoperative GERD (assessed by a symptom-score questionnaire) and was divided into group 1 (those with preoperative GERD symptoms only) and group 2 (those with preoperative and postoperative GERD symptoms). INTERVENTIONS: Laparoscopic AGB was performed according to the pars-flaccida technique. MAIN OUTCOME MEASURES: All patients underwent preoperative and annual postoperative symptom scoring, endoscopy, esophageal barium swallow tests, esophageal manometry, and 24-hour pH monitoring. RESULTS: Mean follow-up time was 33 months (range, 12-49 months). A total of 164 patients (27.9%) were diagnosed as having preoperative GERD symptoms. In 112 (68.3%) of these patients GERD symptoms vanished postoperatively (group 1), whereas 52 patients (31.7%) remained symptomatic after undergoing laparoscopic AGB implantation (group 2). Preoperatively, group 2 patients showed significantly poorer esophageal body motility compared with group 1 patients (20.8% vs 12.8% defective propagations; P = .007). In group 2 the mean symptom scores for dysphagia (0.4 vs 0.9) and regurgitation (0.6 vs 1.4) deteriorated significantly following laparoscopic AGB implantation, respectively. Eighteen patients (34.6%) in group 2 developed esophageal dilatation. CONCLUSIONS: Adjustable gastric banding provides a sufficient antireflux barrier in most of the obese patients with GERD. However, in patients with preoperatively defective esophageal body motility, AGB may aggravate GERD symptoms and esophageal dilatation. Alternative bariatric surgical procedures should be considered in these patients.

Resolution requirements for monitor viewing of digital flat-panel detector radiographs: a contrast detail analysis.

With the introduction of digital flat-panel detector systems into clinical practice, the still unresolved question of resolution requirements for picture archiving communication system (PACS) workstation monitors has gained new momentum. This contrast detail analysis was thus performed to define the differences in observer performance in the detection of small low-contrast objects on clinical 1K and 2K monitor workstations. Images of the CDRAD 2.0 phantom were acquired at varying exposures on an indirect-type digital flat-panel detector. Three observers evaluated a total of 15 images each with respect to the threshold contrast for each detail size. The numbers of correctly identified objects were determined for all image subsets. No significant difference in the correct detection ratio was detected among the observers; however, the difference between the two types of workstations (1K vs 2K monitors) despite less than 3% was significant at a 95% confidence level. Slight but statistically significant differences exist in the detection of low-contrast nodular details visualized on 1K- and 2K-monitor workstations. Further work is needed to see if this result holds true also for comparison of clinical flat-panel detector images and may, for example, exert an influence on the diagnostic accuracy of chest X-ray readings.

Band leakage after laparoscopic adjustable gastric banding.

BACKGROUND: Laparoscopic adjustable gastric banding is effective in inducing weight loss, as well as being minimally invasive, totally reversible, and adjustable to the patient's needs. Nevertheless, leakage of the adjustable balloon is a known complication. The aim of this study was to assess the incidence and reasons for balloon leakage of the Swedish adjustable gastric band (SAGB). PATIENTS AND METHODS: Between January 1996 and December 2002, 566 patients (475 women, 91 men) underwent a laparoscopic SAGB implantation. Two groups of patients were analyzed: patients with early postoperative leakage (Group E) and patients with late postoperative leakage (Group L). All data (age, gender, pre- and postoperative weight, time of weight gain, band filling status) were prospectively collected in a computerized data bank. For the detection of gastric band leakage, radiography and the technetium-99m colloid scintigraphy was used. RESULTS: 25 band leakages were observed in 22 patients (4.4%). All these patients had a silent presentation of band leakage, with weight regain and an ability to eat without major restriction. Band leakages in group E were detected during the band filling period after a median follow-up of 8 months and after 30.3 months (P <0.0001) in group L. In group E, all 13 leakages possibly resulted from inappropriate handling of the device during surgery. In 2 cases in group L, a tear of the balloon had occurred where it is fixed to the band. The other 10 bands showed breaks at the edges of the inner side of the balloon. All leakages could be detected by (99m)Tc colloid scintigraphy, whereas only 58% of the leakages could be detected by radiography. CONCLUSION: Band leakage is a rare complication and should be considered if a patient starts to regain weight. Operative failure as well as material defects may account for this complication. The balloon leakage can effectively be detected by (99m)Tc colloid-scintigraphy.

Storage phosphor radiography of wrist fractures: a subjective comparison of image quality at varying exposure levels.

Image quality of storage phosphor radiographs acquired at different exposure levels was compared to define the minimal radiation dose needed to achieve images which allow for reliable detection of wrist fractures. In a study on 33 fractured anatomical wrist specimens image quality of storage phosphor radiographs was assessed on a diagnostic PACS workstation by three observers. Images were acquired at exposure levels corresponding to a speed classes 100, 200, 400 and 800. Cortical bone surface, trabecular bone, soft tissues and fracture delineation were judged on a subjective basis. Image quality was rated according to a standard protocol and statistical evaluation was performed based on an analysis of variance (ANOVA). Images at a dose reduction of 37% were rated sufficient quality without loss in diagnostic accuracy. Sufficient trabecular and cortical bone presentation was still achieved at a dose reduction of 62%. The latter images, however, were considered unacceptable for fracture detection. To achieve high-quality storage phosphor radiographs, which allow for a reliable evaluation of wrist fractures, a minimum exposure dose equivalent to a speed class of 200 is needed. For general-purpose skeletal radiography, however, a dose reduction of up to 62% can be achieved. A choice of exposure settings according to the clinical situation (ALARA principle) is recommended to achieve possible dose reductions.

Direct digital radiography versus storage phosphor radiography in the detection of wrist fractures.

AIM: To define the value of digital radiography with a clinical flat panel detector system for evaluation of wrist fractures in comparison with state of the art storage phosphor radiography. MATERIAL AND METHODS: Hard copy images of 26 fractured wrist specimens were acquired with the same exposure dose on a state of the art storage phosphor radiography system and a clinical flat panel detector. Image features like cortical bone surface, trabecular bone, soft tissues and fracture delineation were independently analysed by 4 observers using a standardised protocol. Image quality ratings were evaluated with an analysis of variance (ANOVA). RESULTS: Flat panel detector radiographs were rated superior with respect to cortical and trabecular bone representation as well as fracture evaluation, while storage phosphor radiographs produced better soft tissue detail. CONCLUSION: In some of the observed image quality aspects, the performance of caesium iodide/amorphous silicon flat panel detector exceeds state of the art storage phosphor radiography. This makes it well suited for skeletal imaging particularly in trauma as seen in the detection of wrist fractures.