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K Bohndorf

Publications and source records attributed to K Bohndorf.

At least 19 recordsLinked to original sources

[Incidence of major amputations, bypass procedures and percutaneous transluminal angioplasties (PTA) in the treatment of peripheral arterial occlusive disease in a German referral center 1996-2003].

PURPOSE: To determine the current incidence of major amputations, bypass procedures and percutaneous transluminal angioplasties (PTA) in a study population of patients with peripheral arterial occlusive disease in a German referral center. MATERIALS AND METHODS: In a retrospective study, we recruited patients with peripheral arterial occlusive disease who underwent an amputation, bypass procedure, or PTA in the region of the pelvis or lower limbs between 1996 and 2003 at the Augsburg Medical Center. Patients were identified via the hospital database. This was performed with the help of the International Classification of Diseases (ICD 9 and 10), the operation code (OPS), and appropriate invoices. The incidence of PTAs was further estimated with 200 charts. RESULTS: Of 5379 patients, 627 underwent amputation, 1832 a bypass procedure, and 2920 a PTA. The incidence of PTAs increased during the study period from 51.3/100 000/year to 64.4/100 000/year (p < 0.01), while the number of amputations and bypass procedures remained stable. The incidence of PTAs was exceeded by that of bypass procedures only in patients older than 85 years. The age of the amputees decreased during the study period from 72.2 to 70.5 years (p < 0.01). The age of patients who underwent a bypass procedure increased from 67.2 to 69.4 years, and the age of patients who underwent PTA increased from 66.3 to 69.8 years (p < 0.01). Bypass procedures and PTAs were performed in men 6.3 years earlier than in women (p < 0.01). CONCLUSION: The result is a population-corrected need of 8.4/100 000/year major amputations, 23/100 000/year bypass procedures and 64.4/100 000/year PTAs for patients with peripheral arterial occlusive disease within the referral area of our hospital. The performance of major amputations and bypass procedures stagnates, while the incidence of PTAs is increasing.

Adult↗

[Vertebroplasty and kyphoplasty in patients with osteoporotic fractures: secured knowledge and open questions].

Cementoplasty, performed either as percutaneous vertebroplasty or kyphoplasty, has become well established as an effective technique to treat painful vertebral body fractures. It has low complication rates, is successful in alleviating pain, and improves the patients' mobility and quality of life. A series of questions remain open though or are the subject of controversial debate; for example, the results of several biomechanical studies are in part contradictory. Clinical data on subsequent fractures are also still inadequate, although the majority of studies show no elevated rate of subsequent fractures following treatment with cementoplasty in comparison to the natural course in patients with osteoporotic fractures. Kyphoplasty has the advantage of being able to restore the vertebral body height or reduce the kyphosis angle without leading to different clinical outcomes in comparison to vertebroplasty. Biomechanical considerations on whether restoration of the vertebral body's normal shape could reduce the rate of subsequent fractures still need scientific substantiation. Both surgical methods are employed in our clinic. Kyphoplasty seems to us to be indicated when the height of the anterior portion of the vertebral body is reduced by one-third compared to the norm or a kyphosis angle of more than 15-20 degrees is present. The goals of therapy are restoring the shape and reducing the kyphosis angle. This can only succeed, however, in fractures that are not older than 3 weeks. In all other cases vertebroplasty is performed.

Bone Cements↗

Duplex scanning criteria for selection of patients for internal carotid artery endarterectomy.

BACKGROUND: The value of carotid endarterectomy for stroke prevention depends on reliable identification of patients at higher risk for stroke from their internal carotid artery (ICA) occlusive disease than from surgery. This selection of patients is based on the degree of ICA stenosis. Therefore, preoperative diagnostic measures should strive for a prevalence independent probability for disease of 100%. Aim of this prospective study was to obtain clinically applicable duplex scanning criteria for ICA stenosis > or = 70% with a probability for disease of 100%. PATIENTS AND METHODS: In 124 ICA in 62 patients (79% male) angiography and duplex scanning were performed. Degree of stenosis was classified in 4 categories: I < 50%; II 50%-69%; III 70%-99%; IV 100%. Cohen's kappa statistic was used to estimate agreement between both methods within categories. To improve accuracy post-test likelihood for disease was calculated for each point on the receiver operating characteristics (ROC)-curve for peak systolic (PSV) and end-diastolic velocity (EDV), and cut-off points for velocity criteria were set at a positive likelihood of 100%. RESULTS: Diagnostic agreement was good with kappa = 0.77 (95% CI, 0.64-0.90; p < 0.001). For EDV a criterion of > or = 150 cm/sec was associated with a post-test likelihood for disease of 100%. For PSV no appropriate criterion could be detected. CONCLUSIONS: A probability of 100% for ICA stenosis > or = 70% can be achieved by mere preoperative duplex scanning. Vascular laboratory specific validation of duplex scanning criteria should consider prevalence independent post-test likelihood for disease to ensure the value of CEA for stroke prevention.

Aged↗

[Treatment of iatrogenic femoral pseudoaneurysms with thrombin injection--results in 54 patients].

PURPOSE: To evaluate ultrasound-guided percutaneous thrombin injection to treat iatrogenic femoral pseudoaneurysms following catheter interventions. MATERIALS AND METHODS: In a period of 2 years and 11 months, 55 iatrogenic femoral pseudoaneurysms were treated in 54 patients (male : female = 29 : 25) by percutaneous thrombin injection under continuous color Doppler control. Mean maximum diameter of the perfused lumen was 2.5 cm (SD +/- 1 cm). The injected thrombin doses varied between 10 and 2,000 U (median 200 U). RESULTS: Following thrombin injection, the pseudoaneurysm occlusion rate was 100 % (n = 55/55). Complete and persistent occlusion was achieved in 54 of 55 (98 %) pseudoaneurysms. A repeated procedure was necessary in 6 pseudoaneurysms. In one case (2 %), discrete signs of reperfusion were observed after primary occlusion within 24 hours of the initial procedure (lumen diameter 3 x 5 mm), followed by spontaneous thrombosis without further treatment. No complications, in particular no clinically manifest thromboembolic events, were observed. CONCLUSION: Ultrasound-guided percutaneous thrombin injection is an effective and safe method for the treatment of iatrogenic post catheterization femoral pseudoaneurysms.

Aged↗

[Comparison of contrast-enhanced low mechanical index (Low MI) sonography and unenhanced B-mode sonography for the differentiation between synovitis and joint effusion in patients with rheumatoid arthritis].

PURPOSE: To test whether contrast-enhanced low mechanical index (low MI) sonography is superior to non enhanced B-Mode sonography in differentiating synovitis and joint effusion. MATERIAL AND METHODS: In a retrospective study, 22 patients with proven rheumatoid arthritis underwent B-Mode sonography and low-MI sonography of 25 symptomatic joints of the upper and lower limbs. For low-MI sonography, 5 ml Sonovue (Bracco Altana Pharma GmbH, Konstanz) were injected as an intravenous bolus followed by 10 ml of 0.9 % saline solution. Magnetic resonance imaging (MRI) was obtained additionally in 3 joints. With non-enhanced sonography, we diagnosed a synovitis in case of an echogenic and a joint effusion in case of an anechoic mass. With contrast-enhanced sonography, we diagnosed a synovitis in case of enhancement and a joint effusion in the absence of enhancement of the intraarticular mass. RESULTS: In 13 joints, synovitis and joint effusion were differentiated by both non-enhanced and enhanced sonography. In 12 joints, this differentiation was only possible with contrast-enhanced sonography. In 3 patients diagnosed by sonography as having a synovitis, this diagnosis was proven by MRI. CONCLUSION: Contrast-enhanced low-MI sonography is superior to non-enhanced B-Mode sonography in differentiating synovitis and joint effusion.

Adult↗

[Percutaneous vertebroplasty for osteoporotic vertebral compression fractures: experiences and prospective clinical outcome in 26 consecutive patients with 50 vertebral fractures].

PURPOSE: Prospective evaluation of vertebroplasty for osteoporotic compression fractures concerning pain reduction, demand of analgesics and quality of life. MATERIAL AND METHODS: In 26 consecutive patients, 50 vertebral fractures were treated by percutaneous vertebroplasty under fluoroscopic (n = 44) or combined fluoroscopic/CT guidance (n = 6). Prospective follow-up was performed after 6 (for 50 vertebral fractures) and 12 months (for 27 vertebral fractures). Visual analogue scale (VAS) and numeric rating scale (NRS) was applied for the assessment of pain. Subjective quality of life and analgesics demand was documented semi-quantitatively. RESULTS: Mean interval from the beginning of pain symptoms to therapy was 8.5 weeks. Vertebroplasty was technically successful in all evaluated patients. Pain severity decreased from 10 (defined at baseline as initial pain score) to 2.8 after 6 months and 2.7 after 12 months. Subjective quality of life was reported as very well, well or improved in 92 % (n = 26 after 6 months) or 100 % (n = 13 after 12 months). No need for additional analgesic therapy was observed in 69.3 % (n = 26) after 6 months and 61.5 % (n = 13) after 12 months. Eight newly developed vertebral fractures were observed during follow-up, with 5 fractures directly adjacent to previously treated vertebrae. Leakage of polymethyl methacrylate (PMMA) into the intervertebral space or spinal canal was observed in 22 % and 20 % respectively (n = 50 vertebrae) . No neurologic deterioration or complications requiring surgery were observed. CONCLUSION: Vertebroplasty is a successful therapeutic approach for the treatment of osteoporotic vertebral fractures. Persistent improvement of clinical symptoms was shown at follow-up after 6 and 12 months.

Aged↗

[Influence of clinical information on the diagnostic validity of MRI in the detection of abacterial sacroiliitis].

PURPOSE: To evaluate the influence of clinical information on the diagnostic validity of MRI in the detection of abacterial sacroiliitis. Evaluation of sensitivities, specificities, negative (NPV) and positive predictive values (PPV) for MRI with and without clinical information in comparison to a prior defined standard. MATERIALS AND METHODS: The results of routine MRI reports of 65 patients with the clinical suspicion of abacterial sacroiliitis referred by rheumatologists for MR assessment of the sacroiliac joints were retrospectively reviewed. These results were compared to the results of a blinded reading of the same examinations performed without any clinical information. The MRI protocol included T1-SE, STIR and T1-SE contrast-enhanced sequences with fat saturation. All patients were followed for at least four years. The standard of reference was defined by an experienced rheumatologist and included baseline and follow-up data (clinical, laboratory and imaging). Abacterial sacroiliitis was diagnosed in 19 patients. RESULTS: Under routine clinical conditions, MRI revealed a sensitivity of 94.7 % and specificity of 97.8 %. A PPV of 94.7 % and a NPV of 97.8 % were achieved. Without clinical information, MRI revealed a sensitivity and specificity of 64 and 80 %, and a PPV of 49 % and a NPV of 86 %, respectively. CONCLUSION: The additional knowledge of clinical information for the MR diagnosis of abacterial sacroiliitis increases its diagnostic value for the assessment of abacterial sacroiliitis.

Adolescent↗

[Current legal initiative to integrated care - effects of outpatient care in hospitals].

The strict separation of the out-patient and hospital-based health care delivery sectors in Germany leads to deficits in effectiveness and efficiency. Newly introduced legal initiatives to overcome this separation, namely "Ambulantes Operieren" (section 115 b SGB V), "Ambulante Behandlung durch Krankenhäuser" and Disease Management Programs (sections 116a-b SGB V) are described in detail in this article. Their impact on hospital-based health provision for out-patients is discussed. The aim of a better integration of different sectors with a better quality and a more efficient use of resources seems to be the target of these initiatives.

Delivery of Health Care, Integrated↗

Power Doppler sonography with and without echo-enhancing contrast agent and contrast-enhanced MRI for the evaluation of rheumatoid arthritis of the shoulder joint: differentiation between synovitis and joint effusion.

OBJECTIVE: To evaluate patients with clinically active rheumatoid arthritis (RA) of the shoulder for joint effusion and synovitis using conventional sonography, power Doppler (PD) sonography with and without echo-enhancing contrast agent, and contrast-enhanced MRI. DESIGN AND PATIENTS: Twenty-four patients (mean age 64 years) with known RA had one symptomatic shoulder evaluated by conventional gray-scale sonography and PD sonography before and after intravenous administration of the echo-enhancing contrast agent Levovist (300 mg/ml, 2.5 g). The degree and extent of the altered echo pattern in the subacromial bursa, axillary recess and glenohumeral joint seen by conventional gray-scale sonography and the intensity of vascular signals of PD sonography were compared with the findings of MRI obtained with T2-weighted turbo spin-echo sequences and contrast-enhanced T1-weighted fat-saturated spin-echo sequences. MRI was evaluated by two readers in consensus without knowledge of the sonographic findings. RESULTS: MRI, which was used as the reference examination, detected joint effusion in 71% (17/24) and synovitis in 92% (22/24) of the patients. Conventional sonography revealed an abnormal articular echo pattern in 96% (23/24) of the patients, especially in the axillary recess and subacromial bursa, but failed to attribute the altered echo pattern to either fluid or specific synovitis. PD sonography allowed a specific diagnosis of synovitis in 33% (8 patients), which increased to 50% (12 patients) after administration of an echo-enhancing contrast agent. In 42% (10/24) of the patients, the findings of synovitis demonstrated by MRI corresponded to an altered echo pattern by conventional sonography, but vascular signals were absent by PD sonography with or without echo-enhancing contrast agent. CONCLUSIONS: Using MRI as the "gold standard," PD sonography with and without echo-enhancing contrast agent cannot reliably identify synovitis or distinguish synovial inflammation from effusion in the shoulder joint.

Adult↗

[Guidelines of the German Radiological Society for percutaneous vertebroplasty].

In many countries, percutaneous vertebroplasty became a widely accepted therapeutic option in osteoporotic and neoplastic fractures of the vertebral bodies which is employed in more and more patients. Under image guidance the method can be safely performed and provides a high success rate regarding stabilization of vertebral fractures and pain relief. Due to the increasing interest in vertebroplasty in Germany the German Radiological Society-Working Group on Interventional Radiology decided to produce guidelines for percutaneous vertebroplasty. This guidelines are based on the recent standard of knowledge and represent a guide for practical performance of this procedure. Based on the technical development of the method, indications and implementation of the method in multimodal therapy regimens may change over the next years. Therefore, this guidelines are not a rigid body of rules but a basis for an ongoing development adjusted to the scientific progress and the interdisciplinary discussion.

Age Factors↗

[Assessment of the quality of life of patients with peripheral vascular diseases].

The Medical Outcome Short Form 36 is commonly used as a generic quality of life measure in the assessment of vascular disease. The Claudication Scale CLAU-S, the PAVK-86 Fragebogen, and the Walking Impairment Questionnaire WIQ are validated disease-specific questionnaires for intermittent claudication. A disease specific tool for critical ischaemia is lacking. Quality of life of patients with peripheral arterial occlusive disease is not only impaired in the physical functioning domains (mobility, self care, activities of daily living), but moreover in their social and emotional wellbeing. This situation worsens under conservative treatment. Angioplasty and operation produce similar improvements in all dimensions of hrQOL. As radiological interventional procedures just aim to improve hrQOL and do not bring a definite cure for the underlying disease, patients perception of their quality of life should be taken into account both in the indication for angioplasty and for the scientific evaluation of new treatment modalities.

Activities of Daily Living↗

[Endovascular brachytherapy to prevent restenosis after angioplasty].

Endovascular radiotherapy is the first effective prophylaxis of restenosis after percutaneous transluminal angioplasty (PTA) and stenting. The FDA recently approved two devices for the delivery of intracoronary radiation following coronary artery stenting. Published multicenter, double-blind, randomized trials of intracoronary radiation therapy report good results for preventing in-stent restenosis, while the data for the peripheral circulation are still inconclusive. Beta-emitters are easier applicable and probably also safer, whereas gamma-emitters have been more extensively evaluated clinically so far. Primary indication for endovascular brachytherapy are patients at high risk for restenosis, such as previous restenoses, in-stent hyperplasia, long stented segment, long PTA lesion, narrow residual vascular lumen and diabetes. Data from coronary circulation suggest a safety margin of at least 4 to 10 mm at both ends of the angioplastic segment to avoid edge restenosis. To prevent late thrombosis of the treated coronary segment, antiplatelet therapy with clopidogrel and aspirin are recommended for at least 6 months after PTA and for 12 months after a newly implanted stent. An established medication regimen after radiotherapy of peripheral arteries is still lacking.

Angioplasty, Balloon↗

[CT in ureterolithiasis with a radiation dose equal to intravenous urography: results in 209 patients].

PURPOSE: To evaluate a low-dose, nonenhanced helical CT protocol for the diagnosis of renal colic using an effective dose equivalent of radiation not higher than that of intravenous urography. MATERIALS AND METHODS: A new low-dose helical-CT protocol (120 kV; 70 mA; rotation time 0.75 s; collimation 5 mm, pitch = 2) was used to examine 209 consecutive patients with symptoms of renal colic. The initial CT reports were compared with retrograde ureterography, ureteral endoscopy, stone retrieval, surgical or clinical findings. The effective radiation dose was calculated by the method published by Nagel. The prevalence of ureterolithiasis was 70 %. RESULTS: Sensitivity and specificity of the low-dose-helical CT in detecting ureteral calculi were 97.7 % and 96.8 %, respectively. The positive predictive value was 99.3 % and negative predictive value 92.4 %. The mean effective radiation dose equivalent was 0.97 mSv in male and 1.35 mSv in female patients. CONCLUSIONS: The diagnostic value of the reported CT protocol does no differ from previously published protocols. However, the effective radiation dose equivalent is at least 50 % lower than stated in the published protocols. We recommend the low-dose helical CT protocol as the method of choice.

Adult↗

MR arthrography: pharmacology, efficacy and safety in clinical trials.

OBJECTIVE: A meta-analysis was carried out of clinical trials published between 1987 and 2001 in respect of the clinical pharmacology and safety as well as the diagnostic efficacy of gadolinium-DTPA (Gd-DTPA) for direct intra-articular injection before MRI examination. DESIGN: Scientific papers (clinical, postmortem and experimental studies) and information from the manufacturer regarding intra-articular injection of Gd-DTPA that addressed questions of mode of action, optimal concentration and dose, elimination and safety were reviewed. Clinical studies were classified according to their study design. The sensitivity, specificity and accuracy of MR arthrography (MRA) were compared with a "gold standard" (arthroscopy, arthrotomy) and other radiological evidence for different joints. RESULTS: Fifty-two clinical studies of the overall 112 studies addressed aspects of diagnostic efficacy of MRA in patients or in healthy volunteers. The shoulder was the most assessed joint (29 of 52 studies). Good (>80%) or even excellent (90-100%) sensitivity, specificity and accuracy were found for MRA in most indications, especially for the shoulder and knee joints and induced extension of rotator cuff lesions, labrum abnormalities and postoperative meniscal tears. Two millimoles per liter has proven to be the best concentration for intra-articular administration of Gd-DTPA. After passive complete diffusion from the joint within 6-24 h, complete and rapid renal elimination takes place after intra-articular injection. Local safety proved to be excellent after intra-articular administration of Gd-DTPA. Regarding systemic tolerance almost no side effects have been reported, but the same safety considerations apply for intra-articular administration of Gd-DTPA as for intravenous injection. CONCLUSIONS: The diagnostic efficacy of intra-articular MRA in most clinical conditions affecting major joints is greater than that of plain MRI. In some diagnostic problems MRA achieves almost the same sensitivity and specificity as the surgical gold standard. Given a sterile application, the intra-articular administration of Gd-DTPA in a concentration of 2 mmol/l prior to MRI is a safe procedure.

Arthrography↗

Long-term osseous sequelae after acute trauma of the knee joint evaluated by MRI.

OBJECTIVE: To evaluate the frequency and location and to determine the long-term MR changes in patients with edema-like bone marrow abnormalities after acute knee trauma. DESIGN AND PATIENTS: A cohort of 176 consecutive patients in a 29 month period with acute injury of the knee joint was examined with MRI. Forty-nine patients with bone marrow edema-like signal alteration on the initial MR examination were re-evaluated with MRI after a minimum of 2 years (mean 44 months). Signal alterations and contour abnormalities on the initial and follow-up MR examinations were classified. The volume of the edema was also measured. RESULTS: There was a prevalence of post-traumatic edema-like signal changes of 72% in 176 patients. In the follow-up group (n=49) the initial MR examination showed 80 areas of signal change with a mean volume of 15.5 cm3 (range 0.25-175 cm3). Thirty-five (44%) were signal changes without other bony or cartilaginous injuries, 19 (24%) were subchondral impaction fractures and 26 (33%) were osteochondral or chondral fractures. Sixty-nine percent of the lesions were located in the lateral, and 29% in the medial joint compartment. Three percent were patellar lesions. In seven of the 49 patients (14%) eight signal changes were seen on the follow-up MR examination. Six lesions were located in the same anatomic area as on the initial MR examination, and two new lesions had developed. The volume of the bone marrow edema was smaller in all persisting lesions (mean volume 2.26 cm3, range 0.3-4.8 cm3). Deterioration of the subchondral impaction, chondral/osteochondral fracture or lesions resembling osteonecrosis were not found in any patient. CONCLUSIONS: The majority of acute post-traumatic marrow signal changes are found in the lateral compartment and do not show additional osseous or chondral alterations. After a minimum of 2 years acute post-traumatic bone marrow edema-like signal alterations vanish in the majority of patients. Even more severe articular surface injuries such as subchondral bone impaction or chondral/osteochondral fractures will heal without obvious osseous long-term sequelae. Post-traumatic osteonecrosis, as reported in the literature, must be a rare event after acute knee trauma.

Acute Disease↗

Traumatic injuries: imaging of peripheral musculoskeletal injuries.

The current dominant role of conventional radiography must be reassessed at increasingly shorter intervals in view of the continuing emergence of new imaging modalities that are available to diagnose peripheral musculoskeletal injuries. In comparison with conventional radiography, digital radiographic techniques offer advantages for optimization of image quality and dose, such as a wider dynamic range and post-processing of images. Currently, digital luminescence radiography (storage phosphor radiography) is the most commonly used digital method for obtaining radiographs, using the established positioning projections and routines of the film-screen technique. A new process, radiography with flat-panel amorphous silicon detectors, is still under development. Computed tomography is a valuable tool for diagnosing injuries of the peripheral musculoskeletal system, especially when three-dimensional data sets are acquired; these allow reformating images in all planes desired (2D technique) or in a volumetric format (3D technique). Established indications for CT in the peripheral skeleton are hip fractures, wrist injuries and calcaneal fractures; however, CT may be used as a supplement to radiography in every region of the body. Sonography is beginning to play an increasingly important role in trauma. Muscle and tendon injuries are the most common indications, but worthwhile information can be gained of the shoulder, elbow, hip, and knee joints, supplementing conventional or digital radiography. Magnetic resonance imaging effectively visualizes traumatic changes of the skeleton and the peripheral soft tissues. It is the method of choice to detect occult fractures. It can be used to diagnose muscle and tendon injuries. Joint injuries, especially in the knee and the shoulder joint, are common indications for MRI in the posttraumatic setting.

Arm Injuries↗

Magnetic resonance imaging of metastatic disease to the brain with gadobenate dimeglumine.

Seventy-four patients with one to eight proven intraaxial brain metastases received a total cumulative dose of 0.2 mmol/kg bodyweight gadobenate dimeglumine, administered as sequential injections of 0.05, 0.05 and 0.1 m mol/kg over a 20-min period. MR imaging was performed before the first administration (T2- and T1-weighted sequences) and after each injection of contrast agent (T1-weighted sequences only). Quantitative assessment of images revealed significant (P <0.01) dose-related increases in lesion-to-brain (L/B) ratio and percent enhancement of lesion signal intensity. Qualitative assessment by two independent, blinded assessors revealed additional lesions in 22%, 25% and 38% (assessor 1) and 29%, 32% and 34% (assessor 2) of patients after each cumulative dose when compared with combined T1- and T2-weighted pre-contrast images. Significantly more lesions (P < 0.01) were noted by both assessors after the first injection and by one assessor after each subsequent injection. For patients with just one lesion observed on unenhanced T1- and T2-weighted images, additional lesions were noted in 12%, 16% and 28% of patients by assessor 1 following each dose and in 24%, 27% and 30% of patients by assessor 2. Contemporaneously, diagnostic confidence was increased and lesion conspicuity improved over unenhanced MRI. For patients with one lesion observed after an initial dose of 0.05 mmol/kg, additional lesions were noted by assessors 1 and 2 in 9.1% and 11.8% of patients, respectively, after a cumulative dose of 0.1 mmol/kg and in a further 9.1% and 5.9% of patients, respectively, after a cumulative dose of 0.2 mmol/kg. No safety concerns were apparent.

Brain Neoplasms↗