[Electronic distribution of patient records and images through PACS: implementation of data protection at the University Hospital in Freiburg]. / Elektronische Befund- und Bildverteilung aus einem PACS: Umsetzung der datenschutzrechtlichen Aspekte am Beispiel des Universitätsklinikums Freiburg.

In large installations of a Picture Archiving and Communication System (PACS), data protection becomes an issue. Above all, not every employee should have access to all data stored in the system. At the Freiburg University Hospital, we developed a concept of dynamic assignment of authorization, assuring that every physician is authorized to the data of all patients under his care. We describe the technical implementation of data protection developed for the integration of PACS and electronic patient records in Freiburg. The system was installed in January 2001 and the experience of its two years in operation is reported.

Epithelioid angiosarcoma of the aorta.

Primary malignant tumors of the aorta are extremely rare. Review of the literature indicates that there are nearly 100 recorded cases of primary malignant tumors of the aorta. The purpose of this article is to present an additional case of the primary malignant tumors of the aorta which initially has been misinterpretated as atherosclerosic disease. This aortic tumor was of endothelial origin and immunohistochemical studies classified the tumor as an epithelioid angiosarcoma. The treatment resulted in an abdominal aortic repair. MRI of the spine revealed multifocal metastatic disease of the axial skeleton and a subsequent chemotherapy was performed. The patient died 17 months after the initial diagnosis.

Serious complications that require surgical interventions after endoluminal stent-graft placement for the treatment of infrarenal aortic aneurysms.

BACKGROUND: Endoluminal stent-graft placement for the treatment of infrarenal abdominal aortic aneurysms has gained widespread acceptance because it is associated with lower peri-interventional morbidity than conventional transabdominal surgery. In this study the long-term morbidity of the procedure was evaluated. METHODS AND RESULTS: Between September 1994 and December 1998, 150 patients (age, 69.6 +/- 8.49 years; 142 men, 8 women) with abdominal aortic aneurysms were treated with the placement of an intravascular nitinol stent-graft (Stentor [55] and Vanguard-System [95]); there were eight tubular grafts and 142 bifurcated grafts. Initial placement of the stent-graft was successful in 144 patients. Mean follow-up was 49 +/- 25 months. In 13.3% of stent-graft placements we encountered the following complications: 4 cases of migration or dislocation of the prosthesis (30.5 +/- 7.4 months after placement); 2 ruptures of the aorta (26.7 and 15.0 months after placement); 3 recurrent thromboses of the stent-graft (25.5 +/- 5.3 months after placement); 3 endoleaks (27.5 +/- 15.7 months after placement); and 5 infections of the prosthesis (26.6 +/- 16.5 months after placement). There was no correlation between the complications and the type of stent used. All of these patients were treated by surgical replacement of the prosthesis with a Dacron graft. CONCLUSIONS: (1) The results suggest that most complications are due to a continuation of the disease process leading to loosening of the prosthesis. (2) Explantation of the prosthesis and surgical repair is feasible but bears additional risks. (3) Because the onset of reperfusion of the excluded aneurysm cannot be predicted, all patients with infrarenal aortic stent-grafts require frequent computer tomographic follow-up. (4) Finally, the results call for further improvements in the design of the stent-graft.

[Quality assessment using AGIR: results and experience]. / Qualitätsmanagement mittels AGIR: Ergebnisse und Erfahrungen.

PURPOSE: To evaluate whether a new software from the working group for interventional radiology (AGIR) is an appropriate tool for quality assurance in interventional radiology, and presentation of results acquired within the quality improvement process in 1999. PATIENTS AND METHODS: AGIR-defined parameters such as patient data, risk profile, given interventions as well as complications were registered by a recently developed software. Based on monthly data analyses, possible complications were identified and discussed in morbidity and mortality conferences. RESULTS: 1014 interventions were performed in our institution in 1999. According to criteria established by AGIR, the complication rate was 2.7%. In addition and according to SCVIR criteria, complications were distinguished quantitatively in five classes and semiquantitatively in minor and major groups. The result was a minor complication rate of 1.8%, and a major rate of 0.9%. There were no cases of death associated with the intervention. Further strategies were developed in order to reduce the complication rate. CONCLUSION: Extensive quality assurance methods can be integrated in daily routine work. These methods lead to an intensive transparency of treatment results, and allow the implementation of continuous quality improvements. The development of the software is a first step in establishing a nation-wide quality assurance system. Nevertheless, modification and additional definition of the AGIR predefined parameters are required, for example, to avoid unnecessary procedures.

[Explantation of aortic stent-grafts]. / Explantation von Bauchaortenstents - Ursachen, OP-Technik, Ergebnisse, Germany.

BACKGROUND: Endoluminal stent graft placement for the treatment of infrarenal aortic aneurysms (AAA) has gained widespread acceptance because it is associated with lower perinterventional morbidity than conventional transabdominal surgery. In this study the long-term morbidity of the procedure was evaluated. METHODS AND RESULTS: Between 9/94 and 12/98, 150 patients (age = 69.6 +/- 8.5 y; m = 142, f = 8) with AAA were treated by placing an intravascular nitinol stent graft (Stentor, n = 55; Vanguard-System, n = 95; 8 tubular grafts, 142 bifurcated grafts). Initial placement of the stent graft was successful in 144 patients. In 12 % of stent graft placements we encountered one of the following complications (n, days after stent placement): migration or dislocation of the prosthesis (4, 914 +/- 220 d), rupture of the aorta (2, 452 d/802 d), recurrent thrombosis of the stent graft (3, 478 +/- 359 d), endoleak (3, 955 +/- 472 d), infection of the prosthesis (5, 798 +/- 495 d). There was no correlation between the complications and the type of stent used. All of these patients were treated by surgical replacement of the prosthesis with a dacron graft. CONCLUSIONS: 1. The results suggest that most complications are due to a continuation of the disease process leading to loosening of the prosthesis. 2. Explantation of the prosthesis and surgical repair is feasible but bears additional risks. 3. Since the onset of reperfusion of the excluded aneurysm can not be predicted, all patients with infrarenal aortic stent grafts require frequent computer tomographic follow up. 4. Lastly, the results call for further improvements in the design of the stent graft.

[Preoperative examination of potential kidney transplantation donors: value of gadolinium-enhanced 3D MR angiography in comparison with DSA and urography]. / Präoperative Untersuchung potentieller Nierenlebendspender: Wertigkeit der Gadoliniumverstärkten 3D-MR-Angiographie im Vergleich mit der DSA und Urographie.

PURPOSE: To assess a contrast-enhanced standardized MRA protocol for the presurgical evaluation of potential renal transplant donors. METHODS: Twenty-three potential donors for renal transplantations were examined with gadolinium-enhanced, two-phase MR angiograms (1.5 T) and DSA/urography for the number of renal arteries, the presence of aberrant arterial and venous branches, renal artery stenoses and anatomy of the renal collecting system and ureters. The diagnostic value was assessed by evaluating different image processing modalities and interobserver variability. RESULTS: Using maximum intensity projections (MIP) together with multiplanar reformatting (MPR), accessory arteries were detected with a sensitivity/specificity of 100%/98%. Depending on diagnostic experience, exclusive evaluation of MIP yielded a sensitivity/specificity of 67-100%/95-100%. Using MIP/MPR, venous depiction was good in 80%, with MIP solely in 30-40%. At least the proximal third of the ureter was visible in 67%. CONCLUSION: MPR/MIP evaluation of two-phase, contrast-enhanced MRA provides an excellent depiction of renal vessel anatomy for presurgical evaluation of renal transplant donors. Exclusive MIP assessment is less reliable and depends strongly on the examiner's experience. For sufficient visualization of the ureters, either additional measurements or low-dose diuretic injection have to performed.

Pelvic imaging with a selenium-based detector (Thoravision). Comparison with screen-film radiography in 75 patients.

OBJECTIVE: To evaluate whether the selenium detector (Thoravision) provides sufficient diagnostic confidence in digital pelvic imaging compared with a conventional screen-film combination. METHODS: In 75 patients, pelvic imaging with conventional screen-film and isodose selenium radiography using a dedicated postprocessing mode was compared independently by three radiologists. The depiction of cortical and cancellous bone was evaluated in the iliac wings, sacral and pubic bones, acetabulum, femoral head, and trochanter. Demarcation of soft tissue was assessed in the iliac and trochanteric region. RESULTS: Visualization of cortical bone and soft tissue in the iliac area as well as soft tissue and cortical and cancellous bone in the trochanteric region was significantly superior with the selenium detector. However, conventional imaging was better in the trabecular bone of the sacral region, where results with the selenium system were particularly poor. CONCLUSIONS: The selenium detector (Thoravision) is advantageous in imaging soft tissue adjacent to the iliac wings and the trochanter, but results for the cancellous sacral bone are poor. Further modifications of postprocessing modes may lead to improved depiction of this critical pelvic area.

Chest wall infiltration by lung cancer: value of thin-sectional CT with different reconstruction algorithms.

The aim of this investigation was to evaluate whether thin-sectional CT with different reconstruction algorithms can improve the diagnostic accuracy with regard to chest wall invasion in patients with peripheral bronchogenic carcinoma. Forty-one patients with intrapulmonary lesions and tumor contact to the thoracic wall as seen on CT staging underwent additional 1-mm CT slices with reconstruction in a high-resolution (HR) and an edge blurring, soft detail (SD) algorithm. Five criteria were applied and validated by histological findings. Using the criteria of the intact fat layer, HRCT had a sensitivity of 81 % and a specificity of 79 %, SD CT had a sensitivity of 96 % and a specificity of 78 %, and standard CT technique had a sensitivity of 50 % and a specificity of 71 %, respectively. Regarding changes of intercostal soft tissue, HRCT achieved a sensitivity of 71 % and a specificity of 96 %, SD CT had a sensitivity of 94 % and a specificity of 96 % (standard CT technique: sensitivity 50 % and specificity 96 %). For the other criteria, such as pleural contact area, angle, and osseous destruction, no significant differences were found. Diagnostic accuracy of chest wall infiltration can be improved by using thin sectional CT. Especially the application of an edge-blurring (SD) algorithm increases sensitivity and specificity without additional costs.

Contrast-enhanced subtraction MR angiography in occlusive disease of the pelvic and lower limb arteries: results of a prospective intraindividual comparative study with digital subtraction angiography in 76 patients.

PURPOSE: The purpose of this work was to evaluate the feasibility and clinical use of MR angiography (MRA) for examining the pelvic and lower limb arteries in patients with arterial occlusive disease. METHOD: Seventy-six patients with clinical signs of peripheral arterial occlusive disease were included in the study. MRA was performed using a fast contrast-enhanced high-resolution 3D technique that covered the area from the distal abdominal aorta to the distal lower limbs in two examination steps. RESULTS: In all patients, diagnostic images comparable with those of conventional intraarterial digital subtraction angiography (DSA) could be obtained. No false-negative findings were seen in the iliac, femoral, or popliteal arteries. Ten to 16% of the mild stenoses and 6-14% of the severe stenoses, mainly in the crural vessels, were overgraded compared with intraarterial DSA. Particularly in patients with proximal severe obstructions or occlusions, the crural segments could be depicted more clearly due to decreased arterial runoff in conventional angiography. CONCLUSION: The consistency of the excellent depiction of the vascular territories of the distal aorta and the pelvic and lower limb arteries in a standardized setting suggests great potential for the use of MRA in the primary diagnosis of peripheral arterial occlusive disease.

Homing of intravenously and intralymphatically injected human dendritic cells generated in vitro from CD34+ hematopoietic progenitor cells.

Dendritic cells (DC) are professional antigen-presenting cells that can be generated in vitro from CD34+ peripheral blood progenitor cells by recombinant cytokines. These cells have potential implications for immunotherapeutic approaches in the treatment of cancer and other diseases. Physiologically, immature DC in the periphery capture and process antigens, then mature to interdigitating DC and migrate to lymphoid organs, where they activate lymphocytes. However, it is not known if DC generated in vitro have the capacity to traffic in vivo to the lymphoid tissues, such as spleen and lymph nodes. We have investigated whether human radiolabeled DC differentiated in vitro migrate and localize to lymphoid tissues after intravenous and intralymphatic injection. The distribution and localization of the DC were evaluated in five patients with malignant melanoma using serial whole-body gamma camera imaging. Intravenously infused DC demonstrated transient lung uptake followed by localization in the spleen and liver for at least 7 days. DC injected into a lymphatic vessel at the dorsal foot were rapidly detected in the draining lymph nodes where they remained for more than 24 h. These data suggest that DC differentiated in vitro localize preferentially to lymphoid tissue, where they could induce specific immune responses.

Stents for the treatment of aortic aneurysms. Review of devices, technique and results.

The endovascular treatment of abdominal aortic aneurysms has generated a great deal of interest since the early 1990s, and many different devices are currently available. The procedure of endovascular repair has been evaluated in many institutions and the different devices are compared. The first results were encouraging, but complications like endoleak, dislocation or thrombosis of the graft occurred. By the available devices the stent application is only promising, if the known exclusion criteria are strictly respected. Therefore a careful preinterventional assessment of the patient by different imaging modalities is necessary. As the available results up to now are preliminary and the durability of the devices has to be controlled, multicenter studies are required to improve the devices and observe their long-term success in the exclusion of abdominal aortic aneurysms.

Functional MR imaging of the cervical spine in patients with rheumatoid arthritis.

PURPOSE: To evaluate functional MR imaging in patients with rheumatoid arthritis (RA) involving the cervical spine. MATERIAL AND METHODS: We used a device that allows MR examination to be made of the cervical spine in infinitely variable degrees of flexion and extension. Dynamic functional MR imaging was performed on 25 patients with RA. RESULTS: Functional MR imaging was able to show the degree of vertebral instability of the occipito-atlantal or atlanto-axial level as well as the subaxial level. By performing functional MR imaging, we were able to demonstrate the extent of synovial tissue around the dens, and the impingement and displacement of the spinal cord during flexion and extension. The basilar impression, the cord impingement into the foramen magnum, the cord compression, the slipping of vertebrae, and the angulation of the cord were all much more evident in functional than in static MR imaging. CONCLUSION: Functional MR imaging provided additional information in patients with RA, and is valuable in patients who have a normal MR study in the neutral position and yet have signs of a neurological deficit. Functional MR imaging is important in the planning of stabilizing operations of the cervical spine.

Prospective evaluation of bone marrow signal changes on magnetic resonance tomography during high-dose chemotherapy and peripheral blood stem cell transplantation in patients with breast cancer.

RATIONALE AND OBJECTIVES: The authors evaluate bone marrow signal changes on magnetic resonance (MR) imaging during high-dose chemotherapy and peripheral blood stem cell transplantation (PBSCT). METHODS: Fourteen patients with breast cancer without bone metastases underwent four sagittal MR imaging studies with T1-weighted, T2-weighted turbo spin-echo and inversion recovery sequences with short inversion time (STIR) of the lumbar spine: (1) during initial staging, (2) prior to high-dose chemotherapy after two cycles of induction chemotherapy, (3) early after PBSCT with a leukocyte exceeding 2000/microL, and (4) 6 to 8 weeks after PBSCT. Signal intensity ratios of averaged lumbar bone marrow to nucleus pulposus were measured and homogeneity was evaluated visually using a semiquantitative score. RESULTS: Compared with the initial finding (1): Signal intensity ratios were altered significantly at (2): T1-weighted: -22% +/- 14, P < 0.001; T2-weighted: -11% +/- 11, P < 0.01; STIR: +33% +/- 31, P < 0.01; Signal intensity ratios were altered significantly at (3): T2-weighted: -23% +/- 12, P < 0.001, STIR: -22% +/- 23, P < 0.01; and Signal intensity ratios were altered significantly at (4): only STIR: -16% +/- 19, P < 0.01. Homogeneity scores decreased at (3) for T1-weighted and STIR sequences (-1.6 +/- 0.5 to -2.0 +/- 0.7, P < 0.01 and -1.0 +/- 0.5 to -1.4 +/- 0.5, P < 0.01, respectively) and at (4) for the latter sequence (-1.0 +/- 0.5 versus -1.4 +/- 0.5, P < 0.01). At (4), T1-weighted images were less homogenous than initially in 3 of 14 (21%) patients. CONCLUSIONS: Magnetic resonance imaging demonstrates significant alterations of bone marrow composition during PBSCT but allows differentiation of benign therapy-related changes from those known in metastatic disease after completion of PBSCT.

Comparative diagnostic accuracy of magnetic resonance imaging and immunoscintigraphy for detection of bone marrow involvement in patients with malignant lymphoma.

PURPOSE: To compare the diagnostic accuracy of magnetic resonance imaging (MRI) and immunoscintigraphy (IS) for detection of bone marrow infiltration in malignant lymphoma. PATIENTS AND METHODS: In 32 patients with Hodgkin's disease (HD) or non-Hodgkin's lymphoma (NHL), MRI of the axial skeleton and whole-body IS using technetium-99m (99mTc)-labeled monoclonal antibodies were reviewed and compared with iliac crest biopsies. Criterion for marrow infiltration was a positive biopsy or concordant positive results of MRI and IS. RESULTS: In 16 patients (50%), MRI, IS, and iliac crest biopsies were negative for marrow infiltration. Iliac crest biopsy showed infiltration in only four patients (13%). Infiltration was missed in two of 32 patients with IS and in one patient with MRI. In one additional patient, MRI was false-positive because of pelvic hematopoietic hyperplasia. A subset of nine patients (28%) with negative biopsies had bone marrow involvement according to MRI and IS with identical location and pattern of infiltration. In eight of these nine patients, diagnostic imaging indicated marrow involvement only in noncrest marrow. Subsequent biopsy confirmed infiltration in five patients. The clinical course suggested true-positive imaging results in the remaining four patients. Two patients (6%) remained equivocal. Overall concordance of MRI and IS for marrow infiltration was 88% (28 of 32 patients). CONCLUSION: Diagnostic imaging is essential for optimal staging in malignant lymphoma, as blind biopsies appear to have low sensitivity for bone marrow infiltration because of frequent involvement in noncrest marrow. both imaging modalities show a high rate of detection of bone marrow infiltration.

[Osteosclerosis of the vertebrae in radiological diagnosis and its pathomechanism]. / Die Osteosklerose der Wirbelkörper in der radiologischen Diagnostik und ihr Pathomechanismus.

Primarily osteosclerosis is detected in secondary hyperparathyroidism, renal osteodystrophia and some renal tubular disorders. As mentioned, the sclerosis of vertebral body is often prominent in the regions adjacent to the endplates the typical "rugger-jersey-spine". In our study osteosclerosis was detected in about 10% of the patients with renal osteodystrophia. A still unknown defect in vitamin D-metabolism and a increased avidity of the skeleton for calcium may also involved. The result of this accumulation of steroid is a net increase of bone tissue, with or not mineralization. Conventional radiography is the method of choice in detecting typical features.

[Cerebral manifestations of progressive facial hemiatrophy (Romberg's disease). Nuclear spin tomographic findings and literature review]. / Zerebrale Manifestation der progressiven fazialen Hemiatrophie (Romberg-Erkrankung). Kernspintomographische Befunde und Literaturübersicht.

Progressive facial hemiatrophy (PFH) is a sporadic disease of unknown etiology. It is characterized by shrinking and deformation of one side of the face. Potential CNS involvement has repeatedly been suspected in some patients, but is still a matter of controversy. In this article we describe the clinical and MR imaging findings of the CNS in three female patients with PFH and present a comprehensive review of the literature. One of three PFH patients had partial epilepsy. MRI showed ventricular enlargement, white matter lesions, flattening of the cortical surface and meningeal adhesions homolateral to the facial hemiatrophy. Two other patients had completely normal intracranial findings. These findings confirm that cerebral hemiatrophy occurs in a subgroup of PFH patients. The MRI pattern, however, does not seem to be consistent with a simple atrophic or malnutritional process. We consider chronic localized meningoencephalitis with vascular involvement as a possible underlying mechanism for the occasional CNS involvement in PFH.