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A Rieber

Publications and source records attributed to A Rieber.

At least 55 records · Page 3Linked to original sources
PubMed1997

[Infectious spondylitis. A retrospective evaluation of MRI markers].

AIM AND METHODS: The aim of the present study was to evaluate the MRI criteria of infectious spondylitis (spondylodiscitis). The MR images of 23 patients suffering from spondylodisitis (78% unspecific, 22% specific) were retrospectively analyzed. RESULTS: The height of the intervertebral discs involved was normal in 40%, reduced in 43% and increased in 17% of the cases. The most common findings can be summarized in an MR triad: 1) The vertebral bodies involved are hypointense in T1-weighted images (100%) with a lack of delineation of the intervertebral discs (53%). 2) The injection of Gd-DTPA yields an enhancement of the vertebral bodies involved and intervertebral discs (95% and 74% respectively). 3) The vertebral bodies and intervertebral discs are hyperintense in T2-weighted sequences (76% and 90% respectively). When present, a paravertebral or intraspinal extension of the infection was isointense compared with the adjacent involved vertebral body in the majority of the patients. A differentiation between unspecific and specific etiology based on the MR images was not possible. CONCLUSIONS: The vertebral bodies affected were usually hypointense in T1-W with enhancement after the administration of Gd-DTPA and hyperintense in T2-W. The discs involved were usually hyperintense in T2-W and demonstrated an inhomogeneous enhancement.

Contrast Media↗
PubMed1997

Tunnel placement in anterior cruciate ligament reconstruction: MRI analysis as an important factor in the radiological report.

OBJECTIVE: Correct placement of tunnels for anterior cruciate ligament (ACL) reconstruction is of prime importance for the clinical outcome of the patient. In this study, the possibility of using MRI to document tunnel placement and provide a more comprehensive report following ACL reconstruction was explored at no additional cost in patients scheduled for routine knee MRI DESIGN AND PATIENTS: One year after ACL reconstruction, 45 patients underwent clinical examination (IKCD score), radiographic examination, and MRI using a 1.5-T unit. RESULTS: Twenty patients with good tibial and femoral attachment results were found at clinical examination to have a stable knee joint with a full range of motion. In 25 patients with suboptimal placements, examination showed either a stable knee with a decreased range of motion or instability with a normal range of motion. CONCLUSION: Patients' clinical outcome, and the radiographic and MRI findings, correlated closely with the quality of operative tunnel placement. A record of this finding is important for completeness of the radiological report. Furthermore the MRI findings can be used to improve the surgical quality of tunnel placement. Because tunnel placement can be shown adequately with radiography, however, MRI cannot be justified for this reason alone, so such assessment is advised only when MRI is needed to show all postoperative features.

Adult↗
PubMed1997

[MR enteroclysis for nuclear spin tomographic diagnosis of inflammatory bowel diseases with contrast enhancement].

PURPOSE: To evaluate MRI for effectiveness in assessment of intra- and extramural changes in the small intestine. METHODS: 40 patients with known or suspected small bowel disease underwent MR imaging immediately after conventional enteroclysis with barium and a mixture of methyl cellulose and gadolinium-DTPA. RESULTS: In 6 of 24 patients with no pathological findings in conventional enteroclysis, intraabdominal pathology such as thickening of the intestinal wall and an abscess were identified. In the remaining patients, MRI showed good correlation with conventionally obtained data and provided important additional information regarding extraluminal involvement such as enlargement of mesenterial lymph nodes and fistulas as well as abscesses. CONCLUSIONS: MRI, carried out using this technique, provides important additional information regarding intra- and extraluminal changes with good image quality.

Adolescent↗
PubMed1997

[Doubtful mammographic findings: the value of negative MR mammography for tumor exclusion].

PURPOSE: To determine whether the addition of MR mammography (MRM) is useful in excluding malignant lesions and how reliable negative MRM findings are. METHODS: Amongst 694 MRM's, those originally regarded as normal were retrospectively reappraised. 239 female patients were involved. In all these patients there were clinical, sonographic and/or mammographic findings which were not entirely normal but there was no urgent indication for histological clarification. In 46 patients there were, however, histological examinations since the patients themselves insisted on it. In the remaining patients there was clinical, sonographic, mammographic and/or MRM follow-up after 12 to 18 months. RESULTS: In 95.4% (200/239) a carcinoma could be excluded by means of MRM, in 7 patients a carcinoma in situ and in two patients an invasive carcinoma was demonstrated histologically which had not been demonstrated by MRM. Even in retrospect, no abnormality could be found. CONCLUSION: Because of the only moderate sensitivity of MRM in the recognition of carcinoma in situ, doubtful lesions which can be localised, should be biopsied by a stereotactic method. In cases where evaluation is difficult on clinical, sonographic and mammographic findings, MRM is of value in excluding tumours, particularly in patients with increased carcinoma risk.

Adolescent↗
PubMed1997

MRI of breast cancer: influence of chemotherapy on sensitivity.

MR mammography (MRM) seems to be a sensitive method for detection of breast cancer. The effect of cytotoxic agents on the dynamics of contrast medium uptake in primary breast carcinoma or recurrent disease is not known. This study addresses this question and evaluates MRM as a method of monitoring therapeutic success. A total of 13 patients (age range 34-62 years) with histologically confirmed breast cancer were investigated. The patients received neoadjuvant intravenous (iv) chemotherapy. MRM and interpretation of the dynamic measurements were performed in a standardized manner after positioning the patient in a double breast coil. A gradient echo sequence (Flash 3D, TE 5 ms, TR 12 ms, flip angle 25 degrees) was acquired before and 1, 2, 3 and 8 min after intravenous injection of Gd-DTPA 0.15 mmol kg-1 body weight. A T2 weighted SE sequence (TE 103 ms, TR 6900 ms, 4 mm, field of view 350 mm) was also obtained. MRM was performed prior to histological evaluation and after chemotherapy. All cases of malignancy were correctly diagnosed with MRM. Based on MR findings, eight patients were classified as "responders" and the remaining as "non-responders". In the "responders" a flattening of the Gd-DTPA uptake curve after the first cycle of chemotherapy of complete absence of Gd-DTPA uptake after the fourth cycle was observed. The change in Gd-DTPA uptake behaviour led to an underestimation of the extent of tumour in two patients and false negative findings in four patients. MRM provides information regarding response to therapy following the first cycle. MRM does not provide information regarding invasive tumour tissue in "responders".

Adult↗
PubMed1997

MR imaging measurement of the femoral antetorsional angle as a new technique: comparison with CT in children and adults.

OBJECTIVE: Our objective was to determine the accuracy, precision, and reliability of MR imaging as a technique for measurement of the femoral antetorsional angle. SUBJECTS AND METHODS: We used MR imaging to measure anteversion of the femoral neck in 44 patients: 19 children (range, 3-17 years old; mean, 11 years old) and 25 adults (range, 18-83 years old; mean, 29 years old). RESULTS: We found a high correlation between MR imaging and CT measurements (r = 77). On CT, the mean angle for children was 34 degrees and for adults it was 22.2 degrees. On MR imaging, the mean angle for children was 23.22 degrees and for adults it was 15.71 degrees. The mean anteversion angles obtained by CT exceeded those obtained by MR imaging. Mean interobserver and intraobserver agreements were high for MR imaging (r = .97 and r = .97, respectively) and for CT (r = .99 and r = .96, respectively). CONCLUSION: Compared with CT as the gold standard, MR imaging measurement of femoral anteversion allows precise anatomic measurements and produces reliable, reproducible results. MR imaging is recommended for preoperative planning in pediatric patients with femoral rotation osteotomies.

Adult↗
PubMed1997

Musculoskeletal involvement in cystic echinococcosis: report of eight cases and review of the literature.

OBJECTIVE: Our purpose was to describe the morphologic appearance of musculoskeletal lesions in patients with cystic echinococcosis shown by CT and MR imaging. CONCLUSION: Patients with musculoskeletal lesions of cystic echinococcosis typically have cystic structures in adjacent soft tissues. These cysts morphologically resemble abscesses, with peripheral uptake of contrast medium and variable signal intensities on T1-weighted MR images. The absence of calcifications or endovesicular daughter cysts does not exclude the diagnosis of cystic echinococcosis.

Adult↗
PubMed1997

[Abdominal arteriovenous and arterio-portal fistulas: etiology, diagnosis, therapeutic possibilities].

PURPOSE: Arterioportal and arteriovenous fistulas (APF, AVF) are rare vascular disorders occurring as a result of congenital vascular malformation, trauma, iatrogenic causes or neoplasms. The clinical spectrum of presentation ranges from symptom-free individuals to patients with severe portal hypertension or congestive heart failure. While the majority of patients have been treated surgically in the past, interventional radiological procedures are being performed with increasing frequency. To prove this trend we reviewed the international literature. REVIEW: We reviewed the clinical presentation and management of 79 cases reported between 1980 and 1996 in the literature and six own patients. RESULTS: Review of the literature and our own six cases show that these fistulas can be divided in intrahepatic (n = 49, 75%) and extrahepatic fistulas (n = 20, 25%). The most important causes are trauma (n = 29, 37%), iatrogenic induced by procedures (n = 21, 27%) and congenital vascular malformations (n = 10, 13%). APFs and AVFs can be diagnosed by ultrasound, computed tomography and magnetic resonance imaging. Angiography confirms the diagnosis and in many cases allows definitive interventional radiologic treatment. CONCLUSION: Management of AVFs and APFs remains a challenge. However, interventional radiologic procedures provide a safe, low-cost, and effective method for treatment. Due to these facts in the last three years we notice an increasing part of interventional procedures for treatment.

Arteriovenous Fistula↗