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C Düber

Publications and source records attributed to C Düber.

At least 37 records · Page 2Linked to original sources
PubMed2003

Multi-slice spiral CT in routine diagnosis of suspected acute left-sided colonic diverticulitis: a prospective study of 120 patients.

This prospective study evaluated the use of multi-slice CT (MSCT) for detection of clinically suspected left-sided colonic diverticulitis with regard to diagnosis, complications and alternative diagnoses. One hundred twenty patients with clinically suspected acute left-colonic diverticulitis underwent MSCT of the lower abdomen with IV contrast after rectal application of iodic contrast. The MSCT results were compared with histopathological and intraoperative findings or other radiological or endoscopic methods and clinical outcome. Acute diverticulitis was proven in 67 of the 120 (55.8%) patients, which was detected by MSCT with an accuracy of 98% (sensitivity 97%, specificity 98%). Contained perforation or abscess formation were detected with an accuracy of 96% (sensitivity 100%, specificity 91%) and 98% (sensitivity 100%, specificity 97%), respectively. In 31 of 120 (25.8%) patients diagnoses other than diverticulitis caused abdominal pain, which was correctly diagnosed by MSCT in 71%. The MSCT as well as other concurrently performed diagnostic methods showed normal findings and no causes for the patients symptoms in 22 of the 120 (18.4%) patients. Multi-slice CT is reliable in detecting diverticulitis, including extracolic complications, and often reveals other diagnoses; therefore, MSCT is recommended as standard diagnostic procedure in suspected acute diverticulitis.

Acute Disease↗
PubMed2003

[Magnetic resonance imaging in the evaluation of temperature-controlled radiofrequency volumetric tissue reduction].

BACKGROUND: Due to its minimally invasive character, radiofrequency surgery has become a topic of increasing attention, especially with respect to the surgical treatment of sleep-related breathing disorders. Temperature-controlled radiofrequency volumetric tissue reduction is the most common technique employed in these cases. However, despite the increasingly widespread use of this technique, there is little data available on the induced effects in vivo. The aim of the present study was to investigate whether magnetic resonance imaging could be used in the evaluation of the in vivo effects of radiofrequency surgery at the base of the tongue. PATIENTS AND METHODS: Six patients were treated at the base of tongue with radiofrequency surgery. At 4-6, 8-10 and 24 h after surgery, magnetic resonance imaging was performed using an inversion recovery technique (TIRM) and the lesions created were evaluated. RESULTS: The lesions could be visualised at all postoperative measurement times. They appeared as oval hypointense structures encircled by a hyperintense area. Lesion size diminished slightly over time. DISCUSSION: Lesions induced by radiofrequency surgery can be clearly visualised with magnetic resonance imaging. Lesion size may be assessed in relation to energy application. In the future, the treatment of sleep-related breathing disorders may be further optimised with the help of this technique.

Adult↗
PubMed2003

[Emergency diagnostic imaging in mesenteric ischemia].

Diagnostic imaging in patients with suspected acute mesenteric ischemia is started with abdominal ultrasound including duplex sonography of the mesenteric vessels. Despite low sensitivity even in experienced hands, ultrasound is used because operative treatment can be initiated without further imaging if a positive diagnosis is made. Plain abdominal X-rays are usually unspecific in acute mesenteric ischemia and are mainly used to rule out differential diagnoses. Spiral CT (ideally using a multislice technique) can accurately demonstrate morphology of the arterial and venous mesenteric vessels, changes in the bowel wall, and additional mesenteric or peritoneal findings. Therefore, CT has the potential for diagnosis of mesenteric ischemia on a pathological basis. Furthermore, CT is successfully used to confirm or exclude most other causes of acute abdominal conditions. Magnetic resonance imaging (MRI) may be as accurate as CT for the diagnosis of acute mesenteric ischemia and its differential diagnoses. However, MRI is not widely available and therefore not used as an emergency imaging modality so far. Catheter angiography remains the diagnostic gold standard for mesenteric vasculature when spiral CT is not available.

Diagnosis, Differential↗
PubMed2003

[Endovascular therapy of abdominal aortic aneurysm: results of a mid-term follow-up].

PURPOSE: Prospective study to evaluate clinical results and complications of endovascular abdominal aortic aneurysm treatment in a mid-term follow-up. MATERIALS AND METHODS: A total of 122 patients (9 females, 113 males, average age 70.9 +/- 7.9 years) with abdominal aortic aneurysms were treated with stent grafts (53 Vanguard or Stentor endografts, 69 Talent endografts). Group I consisted of 40 patients who had all aortic tributaries of the aneurysm sac occluded prior to endovascular grafting, either spontaneously by parietal thrombosis or by selective coil embolization of the respective ostia preserving collateral circulation distal to the vessel occlusion. Group II consisted of 82 patients and included all cases without or with incomplete coil embolization with at least one patent vessel. Stent grafting was performed in general anesthesia in the first 21 patients, followed by peridural anesthesia in 15 cases, and local anesthesia with conscious sedation in 86 cases. The results were evaluated with Spiral-CT, MRI and radiographs of the endovascular graft, with follow-up examinations obtained at 3, 6, 12 months, and every year. RESULTS: Implantation was successfully completed in all cases without primary conversion surgery, laparotomy, or any significant complication. Mean follow-up was 29 +/- 21 months (maximum 84 months). The 30-day mortality was 0.8 % due to a myocardial infarction 3 days after discharge from the hospital. A total of 47 re-interventions were performed in 29 patients (23.8 %), with 35 re-interventions in 18 cases with Vanguard or Stentor endografts and 12 re-interventions in 11 patients with Talent endografts. 23 percutaneous re-interventions included distal graft extension (n = 11), Wallstents for kinking and limb stenosis (n = 3), and secondary coil embolization of collateral vessels (n = 9). 24 surgical re-interventions included proximal graft extension (n = 6), new endovascular grafts (n = 3), surgical clipping of lumbar and mesenteric artery branches for type-II endoleaks following ineffective secondary coil embolization (n = 1), and femorofemoral crossover bypasses (n = 4). A total of 10 secondary conversion operations were performed because of damage to the membrane (n = 4; 3 Vanguard endografts, 1 Talent endograft), significant caudal migrations (n = 5; 4 Vanguard endografts, 1 Talent endograft) associated with type-I endoleaks (n = 2), limb occlusion (n = 1), disconnection of graft components (n = 1), and significant endoluminal thrombus deposits (n = 1). One patient, who was followed for 82 months, suffered from a significant endoleak for 10 months with increasing aneurysm diameter but he refused surgery. He was admitted with aneurysm perforation and was successfully operated with aortic graft replacement. Compared to group II, the incidence and size of endoleaks was reduced in group I (incidence 19.2 % versus 29.9 %, p < 0.05). Group I demonstrated significantly better aneurysm shrinkage at 36 months follow-up (Delta sagittal diameter - 11.1 +/- 8.4 mm versus - 4.9 +/- 6.2 mm, p < 0.05). CONCLUSION: In selected patients, endovascular aneurysm treatment is an effective alternative to open surgery. It is safely performed in local anesthesia with low mortality rate and a low number of acute complications. Intermediate follow-up revealed re-interventions in around one quarer of all patients, especially when Vanguard or Stentor endografts were implanted. Primary coil embolization of all aortic branches prior to endovascular grafting improves clinical outcome. Insufficient proximal fixation and its consecutive complications remains a major problem of this method.

Aged↗
PubMed2003

[Influence of endoleaks on aneurysm volume and hemodynamics after endovascular aneurysm repair].

PURPOSE: To evaluate the aneurysm volume and the intra-aneurysmatic pressure and maximal pressure pulse (dp/dtmax) in completely excluded aneurysms and cases with endoleaks. MATERIALS AND METHODS: In 36 mongrel dogs, experimental autologous aneurysms were treated with stent-grafts. All aortic side branches were ligated in 18 cases (group I) but were preserved in group II (n = 18). Aneurysm volumes were calculated from CT scans before and after intervention, and from follow-up CT scans at 1 week, 6 weeks and 6 months. Finally, for hemodynamic measurements, manometer-tipped catheters were introduced into the excluded aneurysm sac (group I and II), selectively in endoleaks (group II), and intraluminally for aortic reference measurement. Systemic hypertension was induced by volume load and pharmacologic stress. Pressure curves and dp/dt were simultaneously recorded and the ratios of aneurysm pressure to systemic reference pressure calculated. RESULTS: At follow-up, type-II. endoleaks were excluded in all cases of group I by selective angiography. In contrast, endoleaks were evident in all cases of group II. Volumetric analysis of the aneurysms showed a benefit for group I with an improved aneurysm shrinkage: DeltaVolume + 0.08 %, - 1.62 % and -9.76 % at 1 week, 6 weeks and 6 months follow-up (median, group I), compared to + 1.43 %, + 0.67 %, and - 4.04 % (group II), p < 0.05. In case of complete aneurysm exclusion the ratio of systolic aneurysm pressure to systemic reference pressure was 0.662, 0.575 and 0.385 (median) at 1 week, 6 weeks and 6 months. The corresponding dp/dtmax ratios were 0.12, 0.07 and 0.04, respectively. However, within endoleaks selective measurements showed significantly increased pressure load: the ratios of systolic endoleak pressure to systemic reference pressure and the corresponding ratios for dp/dtmax were 0.882 and 0.913 (median), respectively. These hemodynamic findings were linear from hypotension, physiologic blood pressure to hypertension. CONCLUSION: Occlusion of all aortic side branches of an aneurysm prior to stent-grafting reduces endoleaks and promotes aneurysm shrinkage. Complete aneurysm exclusion significantly reduces systolic pressure and dp/dt max. In contrast, endoleaks showed nearly systemic pressure load and undamped pulsatility.

Alloys↗
PubMed2003

Solitary bone metastasis from myxoid liposarcoma.

BACKGROUND: Extrapulmonary metastasis is more common in liposarcoma than in other soft tissue sarcomas. However, osseous metastases are rare. CASE REPORT: We report the case of a 61-year-old woman with a solitary histologically proven bone metastasis of the right femur from primary myxoid liposarcoma of the left thigh. In September 2000 resection of the primary tumor was performed. Histology showed a high-grade liposarcoma with round cell differentiation. Postoperative radiotherapy with 60 Gy was performed. In a follow-up MRI examination 11 months after initial diagnosis, a suspicious formation in the marrow space of the right proximal femur was detected. CT-guided biopsy was performed and histology showed a metastasis from liposarcoma. PET examination confirmed the metastasis as solitary. Curettage of the metastasis was performed followed by radiotherapy with 60 Gy. The patient was without evidence of disease in the last follow-up. CONCLUSIONS: No standard treatment exists for the management of solitary extrapulmonary metastases from soft tissue sarcoma. Interdisciplinary cooperation is advised and the therapy concept should be chosen individually.

Biopsy↗
PubMed2002

[Quality assurance with teleradiology].

Teleradiology offers many applications for quality assurance in medicine. The spectrum reaches from electronic consultations in emergency or special cases and double reading--along with new models of cooperative work and medical networks--to technical quality assurance and integration into interinstitutional and patient controlled health records. Regional teleradiology networks based on server concepts can fulfill the developing technical and organisational requirements. The increasing mobility arising from smaller radiological equipment and improved accessibility to experts with minimized visualisation and reporting systems will change the radiological world of tomorrow, especially in combination with the usage of knowledge based systems in reference data bases and computer assisted diagnosis (CAD). Teleradiology by itself must be liable to quality assurance measurements to prevent unnecessary radiation exposure or danger to the doctor patient relation.

Computer Communication Networks↗
PubMed2002

[The future of teleradiology: results of Teleradiology Expert Meeting of the Health Network Congress 2001].

Legal prerequisites have substantial influence on the development of teleradiology. At an expert meeting (Mannheim, 8.6.2001) a proposal for a teleradiology article in the new German x-ray ordinance has been set up. An exception of the demand for a doctor trained in radiation protection at the point of examination shall be established for emergency cases. To realize the intended improvement of patient care measurements for quality assurance concerning the medical personnel and processes are necessary. Along with other current developments the basis of secure regional teleradiology networks is now built up.

Forecasting↗
PubMed2002

[Vertebral body stenting. A method for repositioning and augmenting vertebral compression fractures].

UNLABELLED: Purpose of the study was to demonstrate the effectiveness of expanding a fractured vertebral body by transpedicular dilatation and stenting. 7 human cadaveric vertebral bodies from L2 to L5 underwent axia compression until a vertebral burst fracture was provoked. Then, by bilateral transpedicular approach, balloon-catheters were introduced, which were armed with stents, usually used for angioplasty. The catheters were inflated with radiolucent fluid and the stents expanded under radiologic control. After expansion, the balloon was deflated and removed, the stents resting inside the vertebral body, holding their inflated shape. Then, the resulting hole was filled with an injectable biodegradable calcium-phosphate. CT-scans were performed after destruction and after expansion. Morphology before and after expansion was judged, using 3-D reconstructions. Vertebral body strength was measured before destruction and after treatment with an Instron testing machine. RESULTS: Vertebral body shape could be restored. Also impressed central parts of the bony endplate could be elevated by using a convergent approach through the pedicles. There was no collapse of the vertebral body after removing the catheter-balloons The vertebral body strength could be restored up to a physiologic level. This procedure gives new perspectives in the treatment either of osteoporotic compression or traumatic vertebral fracture. By using CT-guided technique, it could be performed by a minimally invasive approach percutaneously.

Aged↗
PubMed2002

[Morphologic and functional assessment of vascular abnormalities of the pulmonary vasculature by breath-hold MR techniques].

PURPOSE: To evaluate breath-hold MR techniques for morphologic and functional assessment of vascular abnormalities of the pulmonary vasculature. PATIENTS AND METHODS: 13 patients aged 11 to 60 years with different vascular abnormalities of the pulmonary vasculature (5 patients with 16 arteriovenous malformations, 8 patients with partial anomalous pulmonary venous return) underwent MR imaging at 1.5 T. For morphological assessment, a contrast-enhanced 3D MR angiography (ce-MRA) was performed after a timing run. Segmented cine- and velocity-encoded GRE sequences were used for delineation of associated cardiac septal defects and for determination of systemic left-to-right or intrapulmonary shunt volumes. Selective intra arterial digital subtraction angiography, cardiac catheterization, and the intraoperative situs served as reference standards. RESULTS: Ce-MRA allowed for detection of all vascular abnormalities and for anatomic characterization of 14/16 arteriovenous malformations. Flow measurements in the feeding arteries allowed for determination of intrapulmonary shunt volumes in 4/5 patients. Flow measurements performed in the pulmonary arteries and the ascending aorta enabled determination of systemic left-to-right shunting in patients with anomalous pulmonary venous return. Cine-sequences clearly depicted associated cardiac septal defects. CONCLUSION: Breath-hold MR techniques allow for morphological and functional characterization of vascular anomalies of the pulmonary vasculature. Therefore, they are the non-invasive method of choice for planning further treatment.

Adolescent↗
PubMed2002

[Endovascular aneurysm treatment: Radiological and macropathological findings of the endoluminal surface of modular stent grafts].

PURPOSE: Characterization of the endoluminal surface of a modular stent graft and correlation of macropathological findings with results of radiological methods. METHODS: Aneurysms of the infrarenal aorta were created in 36 mongrel FBI dogs using autologous material. Endovascular treatment was performed with modular stent grafts using two polyester-covered nitinol stents connected with overlap within the aneurysm. Follow-up was 1 and 6 weeks, and 6 months for 12 animals, respectively. Results were documented using sonography, intravascular ultrasound (IVUS), spiral CT, MRI, and digital subtraction angiography (DSA). After fixation, the aorta was prepared and incised lengthwise. Before histopathological work-up, the different segments were macropathologically characterized and correlated with the respective findings of the radiological methods. RESULTS: 4 cases showed high grade stenosis within the stent grafts and graft occlusion occurred in two cases. The connection sites of these modular stent grafts showed steps and partial separation of the graft components was causative in 5 of these cases. Migration of graft components occurred in three cases, one of them with complete disconnection of the modular device. Irregulartities and deposits on the endoluminal surface were systematically underestimated with all radiological techniques used. IVUS showed moderate concordance concerning deployment and unfolding of the stent graft, however, irregularities of the endoluminal surface were systematically underestimated. Concordance of MRI, sonography, and CT was worse. Contrast-enhanced T1-w MRI detected endoluminal deposits with moderate concordance. However, the thickness of deposits was underestimated. DSA, IVUS, and CT showed only poor concordance with macropathological findings. CONCLUSIONS: The connection site of modular stent grafts predisposes to stenosis, occlusion, and disconnection of the modular device. Stent deployment and unfolding of the membrane might be examined with IVUS. MRI is useful for detecting endoluminal deposits and stenosis. However, radiological methods will underrate irregularities and deposits of the endoluminal surface.

Animals↗
PubMed2002

[Emergency endovascular treatment of acute aortic diseases].

PURPOSE: To investigate the safety and efficacy of emergency treatment of acute aortic diseases with endovascular stent grafts. METHODS: In 11 patients (median age 55 years, range 18 - 85) with acute complications of descending aortic diseases endovascular emergency treatment was performed: traumatic aortic rupture (n = 4), penetrating ulcer with aortobronchial fistula or hematothorax (n = 4), acute type B dissection (n = 2, one with penetration, one with subacute mesenteric ischemia), and symptomatic aneurysm of the thoracic aorta (n = 1) with pain and diameter progression. 15 stent grafts were implanted (Talent n = 11, Vanguard/Stentor n = 4). Stent extension was necessary in 4 cases. In 2 cases graft extension was done during the first procedure (due to distal migration and due to the total length of the aortic aneurysm). In 2 cases graft extension was performed 5 days (due to a new aortic ulcer at the proximal stent struts) and 5 months after the initial procedure (recurrent aortobronchial fistula due to aneurysm progression). 14 of 15 implantations required general anesthesia, one symptomatic thoracic aneurysm was performed in local anesthesia and sedation. RESULTS: 14 of 15 graft procedures were performed using the femoral or iliac approach. One procedure required aortofemoral bypass grafting due to extensive arteriosclerotic stenosis and the stent graft was inserted via the bypass graft. The orifice of the subclavian artery was crossed with bare stent struts in 4 cases without neurological complications. Median follow-up is 27 months (range 6 to 72 months). In traumatic aortic ruptures, immediate sealing of bleeding was achieved and follow-up is inconspicuous at a maximum of 72 months. In cases of aortobronchial fistulas, follow-up is satisfactory (maximum 72 months) despite the necessity for reintervention and graft extension. In one acute type B dissection retrograde dissection of the aortic arch occurred during stent release with stable disease during follow-up without neurological complications. In one type B dissection with mesenteric ischemia the mesenteric blood flow was restored. A second look operation confirmed pulsatile flow in the mesenteric trunk but a total necrosis of the small intestine and the patient consequently died. CONCLUSION: Endovascular treatment is safe and effective for emergency treatment of life-threatening complications in selected acute aortic syndromes. Mid-term results are encouraging, however, regular follow-up is mandatory to recognize late complications of the stent graft.

Acute Disease↗
PubMed2002

[The current value of percutaneous transhepatic biliary drainage].

Percutaneous transhepatic biliary drainage (PTBD) is a well established method in the treatment of obstructive jaundice. Major indications are malignant diseases. PTBD may be necessary preoperatively in cases with severe jaundice or cholangitis or as part of palliative treatment concepts. In the past, it has been proposed that a period of preoperative PTBD may improve the morbidity rates of surgery. Various studies could not prove this theory. The significance of preoperative PTBD has changed, as observed during a 15 years period in our own institution, the indications for preoperative PTBD have decreased by half. At present, the majority of treatments with PTBD are palliative (almost 70 % of all procedures). The diagnostic opportunities of the transhepatic approach (intraductal sonography, cholangioscopy, biopsy) are exploited only in few selected cases. Since the radiological approach ist considered to be invasive and related to serious complications most patients are being referred to endoscopic drainage first. Radiologists are consulted in complicated cases of jaundice and when endoscopic approaches have failed. The retrospective evaluation of more than 1000 procedures over a period of 16 years demonstrates good results with a low rate of serious complications. During the two observed periods of nine and seven years, respectively, there occurred complications like sepsis in 1.9 %/0.5 %, peritonitis in 0.5 %/0.7 %, severe bleeding in 0.5 %/1.5 %, procedure-related death in 0.8 %/0.7 %. The overall rate of serious complications was 5 %/3.4 %. These results are comparable to those of the endoscopic approach with a complication rate of 3.6-14 % and a mortality rate of 0.5 %.

Cholangiography↗
PubMed2002

[New concepts in teleradiology with Dicom e-mail].

UNLABELLED: The recently published Dicom supplement 54 (dicom e-mail) defines a connection between the internet and the medical communication inside hospitals. Up to now vendor specific dicom protocol additions were needed to realize certain teleradiology solutions. The new concept relies on vendor independent standard protocols without specific additions. MAIN FEATURES: client-server solution using the internet designed for emergency medicine integration of various clinical informations approved security concept modularized architecture The concept was realized within the scope of a teleradiology project of the state of Rheinland-Pfalz, Germany. It will be expanded to the state of Baden-Wuerttemberg. Germany in 2002 with over 20 hospitals included.

Computer Systems↗
PubMed2001

[Diagnosis of pancreas tumors: MRI or multidetector spiral CT?].

Recent technical advances in the field of abdominal MRI and multi-detector spiral-CT (MSCT) have resulted in improved diagnostic capabilities of pancreatic tumors. Preliminary data demonstrate slight advantages of MRI in the detection of liver metastases and papillary tumors as well as in the differential diagnosis of pancreatic masses while MSCT might be advantageous in the assessment of vascular infiltration, particular in uncooperative patients.

Diagnosis, Differential↗
PubMed2000

[Budd-Chiari syndrome--a rare manifestation of hereditary thrombophilia].

Budd-Chiari syndrome is a rare manifestation of hereditary or acquired thrombophilia. We saw a case of Budd-Chiari syndrome in a 30-year-old woman leading to initial diagnostic difficulties. She underwent surgical side-to-side shunt and 9 weeks later an almost normal liver could be demonstrated on computerized tomography. Budd-Chiari syndrome should be considered if the Chiari triad with abdominal pain, hepatomegaly and ascites occurs in a patient. If necessary, invasive diagnostic procedures (e.g. angiography) must be performed. Therapeutic options are anticoagulative therapy and porto-systemic shunt, either as a TIPS or a surgical shunt. If severe liver failure occurs or liver cirrhosis is present, orthotopic liver transplantation is an additional option which also cures hereditary thrombophilia.

Activated Protein C Resistance↗
PubMed2000

[Pressure load of the aneurysm sac after endovascular treatment of aortic aneurysm].

PURPOSE: Stent grafting of aortic aneurysms should result in relief of pressure within the excluded aneurysmal sac, however confirming data are not available. This study evaluates the intra-extraluminal pressure translation and translation of maximum pressure increase (dp/dtmax) into the excluded aneurysmal sac after endovascular treatment of experimental aortic aneurysms. MATERIALS AND METHODS: Experimental autologous aneurysms were created surgically using a patch from the sheath of the rectus abdominis muscle in 12 mongrel dogs. After 12 weeks reconvalescence, endovascular treatment was performed viafemoral access using dacron-covered nitinol stents. Spiral CT and angiography were performed at one week and six weeks follow-up and 6 animals each. Laparotomy was performed for hemodynamic measurements. A manometer-tipped catheter was introduced into the excluded aneurysmal sac. A second manometer-tipped catheter was placed intraluminally within the stent graft. Pressure curves and their first derivative dp/dt were simultaneously recorded to calculate the intra-extraluminal transmembraneous pressure transmission. RESULTS: At one week follow-up systolic blood pressure and mean blood pressure were significantly reduced by factors of 0.60 +/- 0.17 (p < 0.01) and 0.78 +/- 0.3 (p < 0.05), respectively in the excluded aneurysm sac. The maximal pressure increase, dp/dt max, was considerably reduced by a factor of 0.06 +/- 0.05 (p < 0.01). However, the diastolic blood pressure was not significantly changed. There were no hemodynamic differences between one and six weeks follow-up. CONCLUSION: In experimental aortic aneurysms, endovascular treatment with stent grafts significantly reduces the systolic peak pressure and dp/dt max in the excluded aneurysmal sac, and thereby significantly reduces the wall stress in the diseased aneurysm wall. Despite complete exclusion of the aneurysm, a considerable pressure load remains in the excluded aneurysmal sac.

Angiography↗