Eduard Jonas

Covered versus uncovered self-expandable nitinol stents in the palliative treatment of malignant distal biliary obstruction: Results from a randomized, multicenter study

BACKGROUND Covered biliary metal stents have been developed to prevent tumor ingrowth. Previous comparative studies are limited and often include few patients. OBJECTIVE To compare differences in stent patency, patient survival, and complication rates between covered and uncovered nitinol stents in patients with malignant biliary obstruction. DESIGN Randomized, multicenter trial conducted between January 2006 and October 2008. SETTING Ten sites serving a total catchment area of approximately 2.8 million inhabitants. PATIENTS A total of 400 patients with unresectable distal malignant biliary obstruction. INTERVENTIONS ERCP with insertion of covered or uncovered metal stent. Follow-up conducted monthly for symptoms indicating stent obstruction. MAIN OUTCOME MEASUREMENTS Time to stent failure, survival time, and complication rate. RESULTS The patient survival times were 116 days (interquartile range 242 days) and 174 days (interquartile range 284 days) in the covered and uncovered stent groups, respectively (P = .320). The first quartile stent patency time was 154 days in the covered stent group and 199 days in the uncovered stent group (P = .326). There was no difference in the incidence of pancreatitis or cholecystitis between the 2 groups. Stent migration occurred in 6 patients (3%) in the covered group and in no patients in the uncovered group (P = .030). LIMITATIONS Randomization was not blinded. CONCLUSIONS There were no significant differences in stent patency time, patient survival time, or complication rates between covered and uncovered nitinol metal stents in the palliative treatment of malignant distal biliary obstruction. However, covered stents migrated significantly more often compared with uncovered stents, and tumor ingrowth was more frequent in uncovered stents.

Nationwide cohort study of post-gastric bypass hypoglycaemia including 5,040 patients undergoing surgery for obesity in 1986–2006 in Sweden

Aims/hypothesisSymptomatic hypoglycaemia with related confusion, syncope, epilepsy or seizures is a newly recognised complication of gastric bypass surgery for obesity. The incidence of these conditions is not known. We therefore studied the incidence of post-gastric bypass hypoglycaemia and related symptoms in patients who have undergone gastric bypass and a reference cohort from the general population of Sweden.MethodsThis is a nationwide cohort study based on national registries with 5,040 persons who underwent gastric bypass, vertical banded gastroplasty or gastric banding for obesity in Sweden between 1 January 1986 and 31 December 2006 and a cohort of ten referents per patient matched for sex and age randomly sampled from the general population. The incidence rates of hospitalisation for hypoglycaemia, confusion, syncope, epilepsy or seizures before and after dates of surgery or inclusion in the reference cohort were studied.ResultsPreoperative incidences of hospitalisation for hypoglycaemia were similar in the surgical and referent cohorts. After gastric bypass surgery, the adjusted hazard ratios were significantly elevated for hypoglycaemia (2.7 [95% CI 1.2–6.3]), confusion (2.8 [1.3–6.0]), syncope (4.9 [3.4–7.0]), epilepsy (3.0 [2.1–4.3]) and seizures (7.3 [5.0–10.8]). The proportions of gastric bypass patients and reference participants affected by hypoglycaemia were very low (0.2% and 0.04%, respectively). There was no increased risk of hypoglycaemia after vertical banded gastroplasty or gastric banding compared with the referent population.Conclusions/interpretationObese persons who have undergone gastric bypass have an increased risk of hospitalisation for diagnoses associated with post-gastric bypass hypoglycaemia, although few patients are affected.

Assessment of hepatic extraction fraction and input relative blood flow using dynamic hepatocyte-specific contrast-enhanced MRI

To assess the feasibility to use dynamic hepatocyte‐specific contrast‐enhanced MRI (DHCE‐MRI) as an imaging‐based liver function test, and to compare two methods for deconvolutional analysis (DA) in healthy human subjects.

Consensus Report of the 4th International Forum for Gadolinium-Ethoxybenzyl-Diethylenetriamine Pentaacetic Acid Magnetic Resonance Imaging

This paper reports on issues relating to the optimal use of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid magnetic resonance imaging (Gd-EOB-DTPA MR imaging) together with the generation of consensus statements from a working group meeting, which was held in Seoul, Korea (2010). Gd-EOB-DTPA has been shown to improve the detection and characterization of liver lesions, and the information provided by the hepatobiliary phase is proving particularly useful in differential diagnoses and in the characterization of small lesions (around 1-1.5 cm). Discussion also focused on advances in the role of organic anion-transporting polypeptide 8 (OATP8) transporters. Gd-EOB-DTPA is also emerging as a promising tool for functional analysis, enabling the calculation of post-surgical liver function in the remaining segments. Updates to current algorithms were also discussed.

Assessment of liver function in primary biliary cirrhosis using Gd-EOB-DTPA-enhanced liver MRI

OBJECTIVES Gd-EOB-DTPA (gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid) is a gadolinium-based hepatocyte-specific contrast agent for magnetic resonance imaging (MRI). The aim of this study was to determine whether the hepatic uptake and excretion of Gd-EOB-DTPA differ between patients with primary biliary cirrhosis (PBC) and healthy controls, and whether differences could be quantified. METHODS Gd-EOB-DTPA-enhanced liver MRI was performed in 20 healthy volunteers and 12 patients with PBC. The uptake of Gd-EOB-DTPA was assessed using traditional semi-quantitative parameters (C(max) , T(max) and T(1/2) ), as well as model-free parameters derived after deconvolutional analysis (hepatic extraction fraction [HEF], input-relative blood flow [irBF] and mean transit time [MTT]). In each individual, all parameters were calculated for each liver segment and the median of the segmental values was used to define a global liver median (GLM). RESULTS Although the PBC patients had relatively mild disease according to their Model for End-stage Liver Disease (MELD), Child-Pugh and Mayo risk scores, they had significantly lower HEF and shorter MTT values compared with the healthy controls. These differences significantly increased with increasing MELD and Child-Pugh scores. CONCLUSIONS Dynamic hepatocyte-specific contrast-enhanced MRI (DHCE-MRI) has a potential role as an imaging-based liver function test. The high spatial resolution of MRI enables hepatic function to be assessed on segmental and sub-segmental levels.

High revision rates after laparoscopic vertical banded gastroplasty

BACKGROUND To evaluate, in a surgical department at a university hospital in Stockholm, Sweden, the long-term results after laparoscopic vertical banded gastroplasty (VBG), with special emphasis on revisional surgery. Few studies are available with long-term results after laparoscopic VBG. Some short-term studies have shown results similar to gastric banding. METHODS All consecutive patients who underwent attempted laparoscopic VBG between 1995 and 2005 were followed up regarding weight loss and the need for revisional surgery. Follow-up was from the date of surgery to the end of the observational period (December 2006). RESULTS In 486 patients, laparoscopic VBG was attempted. Of the 486 cases, 64 were converted to open surgery. Conversions were common in the first patients, with a conversion rate of 4% during the last 100 patients. The mean body mass index at surgery was 42.4 kg/m2. The median follow-up was 3 years (range 0-11). All patients lost weight. A total of 104 patients (21%) required revisional surgery 114 times during the follow-up period, with food intolerance/vomiting and insufficient weight loss the most common reasons. Of the 104 patients, 31 underwent repeat VBG, of whom 10 needed a secondary revisional procedure, and 49 required conversion to gastric bypass, of whom none have required additional revisional surgery. CONCLUSION Laparoscopic VBG is associated with high revisional rates. In the case of failed VBG, repeat VBG seems to be a poor option and conversion to gastric bypass yields better results. We have abandoned VBG as a surgical option in the treatment of obesity.

Consensus report from the 6th International forum for liver MRI using gadoxetic acid

As the utility of liver‐specific magnetic resonance imaging (MRI) increases, it is pertinent to optimize and expand protocols to improve accuracy and foster evolution of techniques; in turn, positive impacts should be seen in patient management. This article reports on the latest expert thinking and current evidence in the field of liver‐specific MRI, as discussed at the 6th International Forum for Liver MRI, which was held in Vancouver, Canada in September 2012. Topics discussed at this forum described the use of gadoxetic acid‐enhanced MRI for the assessment of liver function at the segmental level; to increase accuracy in the diagnosis of liver metastases; to overcome current challenges in patients with cirrhosis, including management of arterial hypo‐/isovascular, hepatobiliary phase hypointense nodules; and the data which would be required in order to recommend the use of this modality in hepatocellular carcinoma management guidelines. Growing evidence suggests that gadoxetic acid‐enhanced MRI can help to improve the management of patients with a number of different liver disorders; however, more data are needed in some areas, and there may be a case for developing an interpretation guideline for gadoxetic acid‐enhanced MRI findings to aid standardization. J. Magn. Reson. Imaging 2014;40:516–529.

Five-Year Results of Laparoscopic Vertical Banded Gastroplasty in the Treatment of Massive Obesity

Background: Laparoscopic surgery appears to offer rapid recovery and low postoperative morbidity.The aim of the present study was to assess the outcome of laparoscopic vertical banded gastroplasty (LVBG) in 154 obese patients with a follow-up of 12-60 months. Patients and Methods: 154 massively obese patients (132 female) with a mean ±SEM body mass index (BMI) of 43.4±0.6 kg/m2 were followed prospectively for an average of 31.7±1.4 months. LVBG was performed using 5 trocars placed in a standard fashion for laparoscopic upper gastrointestinal surgery. A 4-row stapler was used for the vertical staple-line and a stretched polytetrafluoroethylene (Gore-tex®) band was used to reinforce the outlet. After the first 67 cases, the procedure was altered so that a 5-cm length was marked on the band. Results: Conversion to open surgery was performed in 33 cases. All patients lost weight. At 60 months follow-up, the postoperative weight was similar in the open and laparoscopic group.The subjects where 5 cm length was marked on the band had a significantly better weight loss at 36 months (30.4 ±1.2). Both early (<1 month postoperative) and late (>1 month postoperative) complications were more common in the group converted to open surgery. Postoperative stay was shorter in the laparoscopic group. Conclusions: LVBG can be performed safely and results in shorter postoperative stay than openVBG. With adherence to surgical technique (5-cm band circumference), weight-loss is maintained at an adequate level. Complications after LVBG do not exceed open VBG.

Dynamic gadoxetate-enhanced MRI for the assessment of total and segmental liver function and volume in primary sclerosing cholangitis

To evaluate dynamic hepatocyte‐specific contrast‐enhanced MRI (DHCE‐MRI) for the assessment of global and segmental liver volume and function in patients with primary sclerosing cholangitis (PSC), and to explore the heterogeneous distribution of liver function in this patient group.

Treatment of leaking gastrojejunostomy after gastric bypass surgery with special emphasis on stenting

BACKGROUND Gastric bypass is one of the most common operations for morbid obesity. One of the most feared complications is a leak, most commonly encountered in the gastrojejunal anastomosis (GJA), leading to significant morbidity and increased costs. Our objective was to evaluate the effectiveness of stenting leaks in the GJA. The setting was a university hospital in Stockholm, Sweden. METHODS We performed a retrospective analysis of all gastric bypasses from January 2001 to August 2011, with special reference to the treatment of leaks in the GJA. RESULTS A postoperative leak in the GJA occurred in 69 of 2214 patients. The risk was greater with open surgery and revisional surgery. The risk was also greater with age >50 years but not with a body mass index >50 kg/m(2). There was no mortality. In the later part of the series, stents were used, with a stent time of 2 weeks. The migration rate was 23%, and need for restenting was 20%. CONCLUSION It is safe and advantageous to use stents in the treatment of leaks at the GJA. Patients can be on oral nutrition and oral medication, reducing the need for in-hospital care.