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A Rieber

Publications and source records attributed to A Rieber.

At least 19 recordsLinked to original sources

Increase of bone mineral density with sodium fluoride in patients with Crohn's disease.

BACKGROUND AND AIMS: Low bone density with an increased risk of vertebral fractures is a frequent complication in inflammatory bowel disease. Since the aetiology of osteopathia in these patients is different compared to postmenopausal or steroid-induced osteoporosis, no treatment strategy is established. Supplementation of calcium and vitamin D has been shown to prevent further bone loss, but no data are available showing the anabolic effect of sodium fluoride in Crohn's disease. METHODS: We carried out a one-year prospective clinical trial in 33 patients with chronic active Crohn's disease who were randomly assigned to receive either calcium (500 mg b.i.d.) and 1000 IU vitamin D3 only, or retarded-release sodium fluoride (25 mg t.i.d.) additionally. The diagnosis of Crohn's disease had been made at least two years ago, and all patients had received systemic high-dose steroid therapy during the previous year. Eleven of 15 patients who received calcium/vitamin D and 15 of 18 patients who additionally received sodium fluoride completed the study. The primary endpoint of the study was the increase of bone mineral density, measured by dual energy X-ray absorptiometry (DXA) after one year of treatment. Bone-specific alkaline phosphatase and osteocalcin were used as markers for bone turnover. RESULTS: In the calcium/vitamin D only group, bone density was not significantly changed after one year of treatment, whereas in the calcium/vitamin D/fluoride group, bone density of the lumbar spine increased from -1.39+/-0.3 (Z-score, mean +/- SEM) to -0.65+/-0.3 (P<0.05) after one year of treatment. Increase of bone density was positively correlated to the osteoblastic markers bone-specific alkaline phosphatase (r = 0.53) and osteocalcin (r = 0.43). CONCLUSIONS: Sodium fluoride in combination with vitamin D and calcium is an effective, well-tolerated and inexpensive treatment to increase lumbar bone density in patients with chronic active Crohn's disease and osteoporosis.

Adult

MR mammography: influence of menstrual cycle on the dynamic contrast enhancement of fibrocystic disease.

Magnetic resonance mammography (MRM) provides data regarding the nature of tumours based on contrast medium dynamics; fibrocystic changes in the breast, however, may lead to false-positive results. This study investigated whether the contrast medium dynamics of fibrocystic changes are dependent on the menstrual cycle. Twenty-four patients with palpable lumps but normal mammographies and ultrasound studies were examined. The MRM technique was performed during the first and second part of the menstrual cycle using a FLASH 3D sequence, both native and at 1, 2, 3 and 8 min after intravenous application of 0.15 mmol/kg body weight of gadodiamide. The calculated time-intensity curves were evaluated based on the following criteria: early percentage of contrast medium uptake in relation to the native value; formation of a plateau phenomenon after the second minute; the point of maximal contrast medium uptake; and calculation of the contrast enhancing index. During the second half of the menstrual cycle, a generally greater contrast medium uptake was observed. Nevertheless, when further diagnostic criteria, such as continuous contrast medium increase as a function of time, were considered, there was no increased rate of false-positive findings. The phase of the menstrual cycle may affect the specificity of the examination, if only the quantitative contrast medium uptake and the percentage of contrast medium uptake in the first 2 min are considered. A control MRM during the other half of the cycle may then be indicated and additional diagnostic criteria may improve specificity.

Adult

Pancreas: does hyoscyamine butylbromide increase the diagnostic value of helical CT?

Among 50 patients referred for helical computed tomography (CT) of the pancreas, 24 randomly selected patients received 40 mg of hyoscyamine butylbromide to evaluate whether its administration improved image quality and diagnostic findings. Differences between the groups were not statistically significant. It was therefore concluded that hyoscyamine butylbromide does not contribute a diagnostic advantage at helical CT of the pancreas.

Adult

[Pathological bone density in chronic inflammatory bowel diseases--prevalence and risk factors].

INTRODUCTION: Osteopenia and osteoporosis are frequent but often underestimated complications in inflammatory bowel disease. In patients with IBD, several factors could contribute to osteopenia, but the pathogenetic mechanisms are still not completely understood. We carried out a prospective study to evaluate the prevalence and possible etiologic factors for osteopenia and subsequent osteoporosis in IBD-patients. METHODS: 140 patients with inflammatory bowel disease (Crohn's disease n = 125, ulcerative colitis n = 15) underwent clinical and spine radiological assessments. Lumbar bone mineral densities were measured by dual energy X-ray absorptiometry (DXA). Markers of bone formation and resorption and vitamin D were assessed in n = 95 patients. Patients were asked about medication, previous or actual intestinal stenosis, smoking and intestinal resection. A lactose-H2-breath test was undertaken if lactose intolerance was clinically suspected. RESULTS: Compared to age- and sex-matched healthy controls (Z-score), the prevalence of osteopenia (Z < -1) was 62%, while osteoporosis (Z < -2) occurred in 38%. The mean bone density of IBD-patients was osteopenic with no significant differences between Crohn's disease (Z = -1.24) and ulcerative colitis (Z = -1.25). Osteoporotic fractures were seen in three patients (2.1%). Crohn's disease patients with osteoporosis showed a significant lower body mass index (BMI) than patients with normal bone density. 52.9% of patients with manifest osteoporosis underwent systemic steroid treatment in the preceding year, but only 34% of those with normal bone density. Except hemoglobin, none of the biochemical markers showed a significant difference between osteoporosis, osteopenia and patients with normal bone density. CONCLUSION: The results show a high prevalence of osteopenia and osteoporosis in IBD. Since osteoporosis is often associated with low body mass index, multiple intestinal resections and previous systemic steroid treatment, we suggest a bone densitometry in these patients. Since etiology of osteoporosis in IBD is multifactorious and not completely understood, there is still no standard treatment. The effect of osteoanabolic and antiresorptive agents must be evaluated in further studies.

Adolescent

[Preoperative assessment of asymptomatic adnexal tumors by positron emission tomography and F 18 fluorodeoxyglucose].

AIM: To evaluate use of F-18-FDG-PET in assessment of dignity of asymptomatic adnexal masses. METHODS: 85 asymptomatic patients with suspicious, asymptomatic adnexal masses were evaluated. Static FDG-PET (Exact HR+ or ECAT 931) imaging of the abdomen was performed following application of 222-555 MBq F-18-FDG. Iterative reconstruction was applied. PET data were analysed visually, at first without and second together with MRT images. Final diagnosis was made by histopathology. RESULTS: FDG-PET allowed correct identification of 4 of 8 malignant adnexal tumors. False negative results were obtained in 2 adenocarcinomas stage pT1a and 2 borderline-tumors. In 60 out of 77 benign adnexal masses malignancy could be excluded. False positive FDG-uptake, partly because of misinterpretation of gastrointestinal activity, was found in 3 inflammatory processes, 1 teratoma, 1 benign schwannoma, 1 dermoid cyst, 1 benign thecoma, 1 serous cyst, 1 serous cystadenoma, 2 mucinous cystadenomas, 2 corpus luteum cysts, 3 endometriosic cysts and 1 sactosalpinx. The overall sensitivity and specificity of FDG-PET alone were 50% and 78%. Evaluation together with MRT images showed a sensitivity of 50% and a specificity of 86%. CONCLUSION: Sensitivity of FDG-PET in detection of borderline-tumors and early stage ovarian cancer seems to be limited. Low incidence of malignant ovarian tumors requires for assessment of dignity a procedure of high specificity, that is not reached by FDG-PET neither without nor together with MRT images for topographic orientation. Therefore use of FDG-PET for assessment of dignity in suspicious, asymptomatic ovarian tumors is limited.

Adolescent

[MRI of the abdomen combined with enteroclysis in Crohn disease using oral and intravenous Gd-DTPA].

In spite of the improved MR-diagnosis of the abdomen, MRI is not used as a routine method for the diagnosis of inflammatory small bowel disease. The aim of this study was--after optimazation of the bowel opacification--the correlation of the findings obtained with enteroclysis and MRI in patients with known Crohns' disease. 60 patients between 17 and 72 years of age were investigated. First, an enteroclysis was performed in typical manner. The applicated methylcellulosis was blended with positive oral MR contrast media (Magnevist oral, Schering). After enteroclysis, MRI of the abdomen was performed using T1- and T2-weighted breathhold sequences (Flash 2D pre- and postcontrast and TSE) in axial and coronal planes. The length of the affected bowel and the stenosis seen with enteroclysis correlated well with the visible thickening of the small bowel wall and the stenosis seen in MRI. Using MRI, additional findings could be obtained in 28 patients, such as fistulas, abscesses or a hydronephrosis, or a better assessment of the stenosis was possible with MRI, because of the avoidance of overshadowing of the affected bowel loop with MRI. A brilliant MR-tomographic imaging of the small bowel is possible under the condition, that the small bowel contrast is optimal. The main prerequisite is a large filling volume of the small bowel to reach a homogeneous contrast and a good distension of the small bowel lumen.

Administration, Oral

MRI follow-up of pisiform bone transposition for treatment of lunatomalacia.

OBJECTIVE: Transposition of the pisiform bone is an operative treatment for lunatomalacia. The postoperative viability of the transposed pisiform bone is difficult to assess. The purpose of the study was to evaluate the utility of MRI for postoperative assessment of viability of the pisiform and lunate bones. DESIGN AND PATIENTS: Six patients who underwent transposition of the pisiform for treatment of lunatomalacia, were assessed pre- and postoperatively with conventional radiographs (including tomography), CT and MRI. RESULTS: Conventional radiographs, conventional tomograms and CT were all useful in demonstrating the location of the transposed pisiform. CT showed the transposed pisiform without superposition. However, neither CT nor conventional techniques provided information regarding viability of the pisiform. In all patients investigated in the first year following surgery, T1-weighted MR images showed high signal intensity in the transposed bones. In all patients investigated after 1 year, the signal intensity decreased to an intermediate level on T1-weighted images. Enhancement following contrast medium administration in the transposed pisiform and the lunate was noted in all patients, indicative of viability. CONCLUSION: Contrast-enhanced MRI is able to provide important information regarding the viability of the transposed pisiform and the remaining parts of the lunate. Thus, contrast-enhanced MRI provides an improved means of postoperative assessment regarding short-term follow-up following pisiform transposition. In the long-term follow-up conventional radiography and CT may be equal to MRI in showing increasing sclerosis and/or fragmentation.

Adolescent

Magnetic resonance epidurography with gadolinium-DTPA.

The aim of this study was to evaluate and describe MRI epidurography as a new imaging tool. Five volunteers and one patient were investigated with MR epidurography after injection of 20 ml Gd-DPTA solution (1:250/1 ml Gd-DPTA/250 ml normal saline). Magnetic resonance epidurography is possible. With fat-suppression techniques, the contrast between Gd-DPTA solution in the epidural space and surrounding soft tissue proved adequate. Using the multiplanar capability of MRI with MR epidurography coronal and sagittal projections similar to conventional epidurography, axial slices comparable to CT epidurography can be obtained. Magnetic resonance epidurography is superior to conventional and CT epidurography. Presently, due to high costs as compared with conventional and CT epidurography, MRI is not suitable for the routine monitoring of peridural catheters, but it may have a place in the future with decreasing costs for MRI and for the evaluation of patients with spine pathology, especially in describing epidural processes.

Contrast Media

[Value of dynamic MRI in the diagnosis of hypophyseal microadenomas].

PURPOSE: To evaluate dynamic MR imaging of the pituitary gland. MATERIAL AND METHODS: 19 patients with suspected mass lesions of the pituitary gland were examined at 1.5 Tesla with dynamic and standard MRI using a Turbo-FLASH sequence (1 image/s for 40 s). RESULTS: In 13/19 patients microadenomas were detected. One of the 13 microadenomas was detected using dynamic imaging and was not seen on standard MRI. The remaining 12 microadenomas were diagnosed with standard MRI. CONCLUSION: Dynamic imaging of the pituitary gland is a time-consuming and costly diagnostic technique. If laboratory results suggest the presence of a microadenoma and conventional MRI is unable to localise it, dynamic imaging should be performed.

Adenoma

[Temperature stress for patients in routine magnetic resonance examinations].

PURPOSE: To determine energy exposure and temperature changes in routine magnetic resonance imaging practice. MATERIALS AND METHODS: Body core and skin temperatures were compared in 155 persons (143 patients, 12 volunteers) undergoing routine magnetic resonance examinations with a 1.5 T field-strength magnetic resonance tomography unit using a fluoroptic temperature measurement system. RESULTS: Average applied energy was 0.3 W/kg for whole body and 1.92 W/kg for spatially localized SAR. The maximum whole-body SAR was 1.43 W/kg spatially localized. Body core temperatures differed from those of the control group by a median 0.1 degree C and only a few patients (16.8%) exceeded the limit (+/- 0.5%) at which regulatory mechanisms set in. All patients remained within the normal physiological circadian temperature range (+/- 1 degree C). Skin temperature rose a median 0.49 degree C, with a maximal increase of 5.31 degrees C, which may be considered to be within the limits of physiological temperature change. CONCLUSIONS: Clinically relevant warming of the body is unlikely in routine magnetic resonance imaging practice.

Adolescent

[MRCP (magnetic resonance cholangiopancreatography)--an assessment of current status].

For the first time, magnetic resonance cholangiopancretography (MRCP) provides images of the biliary and pancreatic ducts based on 3D data similar to those we are used to from endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC). Extraordinarily impressing is the fact that no contrast media have to be applied. The following manuscript shows technical basics and the development of this technique from gradient echo sequences to the recent single-shot techniques. Furthermore possibilities and limitations of MRCP will be discussed with respect to certain illnesses.

Bile Duct Neoplasms

[Diagnosis of gallstone ileus].

Gallstone ileus is a rare disorder, which, because it is often misdiagnosed preoperatively, may become life-threatening. The classic triad of Rigler (aerobilia, small bowel ileus and a calcified, dystopic stone) is visualized on abdominal plain films in only 14-35% of cases. Further work-up includes ultrasound, upper gastrointestinal series with water soluble contrast medium and computed tomography (CT). CT is especially reliable in demonstrating all three criteria.

Aged