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K Eichler

Publications and source records attributed to K Eichler.

At least 19 recordsLinked to original sources

[Cardiovascular prediction rules: problems for application in practice results of a workshop].

Guidelines for primary prevention of cardiovascular disease recommend a management based on global cardiovascular risk calculated with prediction rules. While cardiovascular prediction rules are applied as a tool to estimate risk, Guidelines describe which consequences to be drawn based on this risk information. We performed a workshop to discuss open questions for application of prediction rules in primary care. Technical aspects may not be a problem, however, additional barriers for application in daily routine exist. First, accuracy of risk estimation is unclear for some of the prediction rules. Second, risk factors, which are intuitively relevant (like obesity), are lacking in most of the prediction rules. Third, differences between guidelines and prediction rules are sometimes not clear for the general physician. In this article we want to answer the most important questions, which have been discussed during the workshop.

Coronary Disease↗

Determination of the optimal MRI sequence for the detection of malignant lung nodules.

OBJECTIVE: For staging, follow-up and even screening (www.screening.info) an "all-in-one" imaging examination is desirable. In the concept of whole body MRI, lung imaging prevails as the weakest link. The purpose of our study was to determine the optimal MRI sequences for the detection of malignant lung nodules. PATIENTS AND METHODS: On the basis of 6 lung cancer, 46 metastases and one tuberculoma in 13 patients eight MRI sequences--HASTE, IR-HASTE, fat saturated TrueFISP, STIR, VIBEipat = 2, and contrast-enhanced (CE) VIBE (with ipat = 2, 0, 4) performed with parallel imaging and 12 matrix coil elements--were compared in terms of contrast-to-noise ratio (CNR) and quality in the visualization of the lung nodules using multidetector CT as standard of reference. The parameters of the sequences were pragmatically selected to minimize the imaging time to allow for imaging the entire lung within one breathold interval. RESULTS: The STIR sequence was found to be the best for detecting malignant lung nodules (p<0.01) followed by the FS TrueFISP, CE VIBE subsetipat = 0, CE VIBE subsetipat = 2, IR-HASTE, HASTE, CE VIBE subsetipat = 4, and VIBE. The STIR sequence visualized malignant nodules down to 2 mm in size and did not display the 19 mm tuberculoma. CONCLUSION: The STIR sequence should be included in future studies investigating if MRI can compete with CT in the early identification (detection and classification) of malignant lung nodules.

Aged↗

MR-guided biopsies of lesions in the retroperitoneal space: technique and results.

The purpose of this study was to evaluate the safety and precision of MRI-guided biopsies of retroperitoneal space-occupying tumors in an open low-field system. In 30 patients with indistinct retroperitoneal tumors [paraaortic lesion (n=20), kidney (n=2), suprarenal gland (n=3) and pancreas (n=5)] MR-guided biopsies were performed using a low-field system (0.2 T, Magnetom Concerto, Siemens, Germany). For the monitoring of the biopsies T1-weighted FLASH sequences (TR/TE=160/5 ms; 90 degrees ) were used in all patients and modified FLASH sequences (TR/TE=160/13 ms; 90 degrees ) in ten patients. After positioning of the needle in the tumors 114 biopsy specimens were acquired in coaxial technique with 16-gauge cutting needles (Somatex, Germany). The biopsies were successfully performed in all patients without vascular or organ injuries. The visualization of the aortic blood flow with MRI facilitated the biopsy procedures of paraaortic lesions. The size of the lesions ranged from 1.6 to 7.5 cm. The median distance of the biopsy access path was 10.4 cm. Adequate specimens were obtained in 28 cases (93.3%) resulting in a correct histological classification of 27 lesions (90%). In conclusion, MR-guided biopsies of retroperitoneal lesions using an open low-field system can be performed safely and accurately and is an alternative to CT-guided biopsies.

Adult↗

Women's experiences with low-risk singleton in-hospital delivery in Switzerland.

OBJECTIVE: To assess maternal and neonatal clinical short-term outcomes and women's experiences with singleton low-risk in-hospital deliveries in a routine care setting. METHODS: In 13 community hospitals in the Cantons of Zurich (10), St. Gallen (2) and Schwyz (1), participating in the "Canton of Zurich Outcomes Project", trained hospital staff recorded clinical outcome data. Patients completed a questionnaire at the end of the hospital stay. Over two measurement cycles, 3395 eligible women entered the study and 2079 (61%) returned the questionnaire. RESULTS: Sixty-seven percent of women had spontaneous and 11% had assisted vaginal deliveries, 12% delivered by emergency, and 10% by elective Caesarean section. The episiotomy rate in vaginal deliveries was 46% (95% CI 44-48%). Ten percent of neonates had umbilical cord artery pH < or =7.15 (95% CI 9-11%) and Apgar scores at five minutes were < or = 7 in 3% (95% CI 2.5-3.6%). Reporting negative experiences with hospital care and an insufficient state of knowledge at discharge were strongly associated with mode of delivery. The top three issues new mothers were most likely to report about feeling little or not informed about were postpartum pelvic floor exercises (22%), management of vaginal bleedings (12%), and alternatives of infant feeding (10%). CONCLUSION: In a setting of routine care poor short-term outcomes were rare in women giving birth in hospitals, and neonates and most mothers were discharged with a level of information that at least ensured a smooth transition to follow-up maternal care. Poor clinical results and patient-reported negative experiences concentrate in few individuals. Restrictive approaches that reduce the frequency of instrumental vaginal delivery, and routine episiotomy remain an important objective for quality improvement.

Adult↗

[Laser-induced thermotherapy of lung metastases and primary lung tumors].

We present laser-induced thermotherapy (LITT) of primary and secondary lung tumors analysing indications and technical concepts. Thirty patients with lung metastases of different primary tumors (n=24) as well as localized lung tumors (n=6) were prospectively treated in 41 sessions using laser-induced thermotherapy (LITT). An MR-compatible puncture system was used with direct puncture technique. The puncture was performed via CT guidance in care vision technique. Eight patients were thermoablated using MR tomographical monitoring, 22 patients using CT monitoring. Local therapy effects, tumor control rate, side effects, complications, and survival were evaluated. In 74% of cases (28/38 lesions) of 24 patients with lung metastases and in all cases of the 6 patients with lung carcinoma a complete local ablation could be achieved. The complication rate (pneumothorax) was 9,8%. One patient with bronchial carcinoma had to be thoracotomized and resected. 93% of the patients are still alive. Percutaneous LITT of lung tumors permits a complete ablation of lung metastases and lung carcinomas with a low complication rate. Indications for the procedure were defined for patients with no more than 5 metastases up to 3 cm in size.

Adult↗

[Percutaneous thermoablation of pulmonary metastases. Experience with the application of laser-induced thermotherapy (LITT) and radiofrequency ablation (RFA), and a literature review].

PURPOSE: Evaluation of technical aspects, local efficiency and complications of thermoablative procedures, such as radiofrequency ablation (RFA) and laser-induced thermotherapy (LITT), in percutaneous lung metastases. MATERIALS AND METHODS: Techniques of thermal ablative procedures of RFA and LITT are presented. For primary positioning, monitoring and therapy control, computed tomography (CT) or magnetic resonance imaging (MRI) was performed. Different monopolar systems and one bipolar system were available for RFA and two different cooling systems for LITT. Percutaneous CT-guided RFA was performed on 32 metastases in 20 patients and percutaneous LITT on 34 metastases in 24 patients. Inclusion criteria were metastases < or = 5 cm in diameter in unresectable patients with up to 3 metastases per lung. All treatments were performed on outpatient basis using analgosedation. RESULTS: In our patient group, all patients tolerated both the RFA and LITT procedures well with mild sedation. The pneumothorax rate was 15 % (5/32 procedures) for the RFA group and 12 % (4/34 procedures) for the LITT group, without insertion of a chest tube. In all RF ablations, a complete "roll off" (increase in impedance) was achieved. Local tumor control rate in the 6-month follow-up was 85 % for RFA and 91 % for LITT. Nineteen of the 20 patients treated are still alive, one patient died from tumor progression. CONCLUSION: Both pulmonary RFA and LITT allow safe thermal ablation of pulmon arg metastases with a low complication rate and an acceptable tumor control rate.

Adult↗

[Uterine adenomyosis in infertile patients: MR imaging findings and clinical conclusions].

PURPOSE: To evaluate the clinical value of magnetic resonance imaging (MRI) of the uterus and the pelvis in infertile female with symptomatic endometriosis for the assessment of uterine morphology and function. MATERIALS AND METHODS: Forty-one infertile women (mean age: 33.2 years) with symptomatic endometriosis documented by laparoscopy were evaluated with high-field MRI (Sonata, Siemens) using T2- and T1-weighted sequences. In addition, the patients underwent hysterosalpingoscintigraphy (HSSG) for evaluation of the uterotubal transport capacity. Pathologic findings of the uterine junction zone were correlated with the laparoscopic results, clinical symptoms and uterotubal transport capacity. RESULTS: Adenomyosis was diagnosed on T2-weigthed MR-images in 35 (85.4 %) patients (focal adenomatosis in 26 patients and diffuse adenomatosis in 9). Patients showing signs of adenomyosis tended to be older than patients without adenomyosis (mean age 34.1 years vs. 30.1 years) and showed a longer history of symptomatic endometriosis. A positive transport capacity in HSSG was observed in 73.1 % (19/26) of the patients with focal adenomyosis and in only 22.2 % (2/9) of patients with diffuse adenomyosis. In 83.3 % (5/6) of the patients without signs of adenomyosis, a positive uterotubal transport was documented. CONCLUSION: MRI of the uterus is a helpful diagnostic tool for the diagnosis of adenomyosis and for planning further therapies. Patients with the diagnosis of adenomyosis showed a reduced uterotubal transport capacity that depended on the severity of adenomyotic changes and might be a possible cause of infertility.

Adult↗

MR-guided laser-induced thermotherapy (LITT) of liver tumours: experimental and clinical data.

MR-guided laser-induced interstitial thermotherapy (LITT) is a percutaneous, minimally invasive treatment modality for treating liver lesions/metastases, soft tissue tumours and musculoskeletal lesions. In this group, MR-guided LITT is currently performed under local anaesthesia on an out-patient basis with a specially designed saline-cooled laser application system. Nd:YAG laser (1064 nm wave length) was used for tumour ablation. Magnetic resonance imaging (MRI) using both open and closed MR units has proven clinically effective in validating the exact positioning of optical fibres. It also allows for real time-monitoring of thermal effects and the evaluation of treatment-induced coagulation necrosis. In liver tumours, percutaneous MR-guided LITT achieves a local tumour control rate of 98.7% at 3 months post-therapy and 97.3% at 6 months with metastases smaller than 5 cm in diameter. The mean survival rate for 1259 patients with 3440 metastases treated with 14 694 laser applications at the institute (calculated with the Kaplan-Meier method) was 4.4 years (95% confidence interval: 4.1-4.8 years) and median survival was 3.00 years. No statistically significant difference in survival rates was observed in patients with liver metastases from colorectal cancer vs metastases from other primary tumours. The rate of clinically relevant side effects and complications requiring secondary treatment was 2.2%. The clinical use of MR guided LITT (size < 5 cm, number < 5) is justified in patients with liver metastases of colorectal and/or breast cancers if the inclusion criteria are carefully observed. Further indications for MR guided LITT include recurrent cancer lesions in the head and neck, lung metastases and bone and soft tissue lesions.

Humans↗

[Anticoagulatin in atrial fibrillation--status of therapy in a network of physicians].

Despite of sound evidence, that oral anticoagulation reduces substantially the incidence of stroke-events in patients with atrial fibrillation and concomitant risk factors, in daily practice only a part of these patients is in fact treated with anticoagulation. The aim of this cross-sectional study was to evaluate to which extent existing guidelines for the treatment of patients with atrial fibrillation are transformed in the "real world" context of a Swiss urban network of primary care providers. The greatest part (88.4%) of the included patients with atrial fibrillation had a high risk for thromboembolism and herewith the indication for anticoagulation was given. For a primary care collective the amount of patients with anticoagulation was high: 74.1% did receive this kind of preventive therapy. 89% had robust International normalized ratio (INR) values within the recommended range (INR 2.5-3.5). The most common reasons not to prescribe oral anticoagulation were: old age (17.5%; mostly in combination with other reasons), risk of falls (16.5%), medical indication not given (16.5%). Thus the recommendations of the guidelines have been transformed into practice for a bigger part of the included patients. Given these results a broadly implemented quality-improvement-project to bring up the anticoagulation rate even higher hardly seems to be efficacious and is presently not of top priority in this network of primary care providers.

Adult↗

[Interstitial photodynamic laser therapy for liver metastases: first results of a clinical phase I-study].

PURPOSE: Development and evaluation of a new photodynamic treatment technique for the laser therapy of liver malignancies MATERIAL AND METHODS: The combination with new catheter systems enables the use of the photodynamic therapy (PDT) to treat also tumors in parenchymal organs. So far it is mainly used to treat superficial or endoluminal tumors. The presented study is part of a multicenter phase I-study. We treated 5 patients with colorectal liver metastases with the new photosensitizer SQN 400 and following interstitial photodynamic laser treatment. Evaluation of tumors were performed by contrast-enhanced CT scans. RESULTS: In the contrast enhanced CT scans the development of a complete necrosis within a radius of 1 cm around every single fibre could be shown. Additional the ablation of tumors with the combined use of several fibres is possible. Severe complications or toxicities were not observed. CONCLUSION: The photodynamic laser therapy of liver malignancies is a minimal invasive procedure with little side effects which produces sharply defined yet small volumes of necrosis.

Aged↗

[MR-guided biopsies of undetermined liver lesions: technique and results].

PURPOSE: To evaluate safety and precision of liver tumor biopsies performed in an open low field system using different sequence techniques. MATERIALS AND METHODS: In 47 patients with liver tumors, MR-guided biopsies were performed in a low field system (0.2 Tesla, Magnetom Open, Siemens) using two different sequences. The procedure was monitored with T1-weighted FLASH sequences (TR/TE = 100/9; 70(3)) in all patients and with FISP-Rotated-Keyhole-sequence (TR/TE = 18/8; 90(3)) in additional 20 patients. After positioning of the needle tip in the tumors, 166 biopsy specimens were acquired with 16 G cutting needles (Somatex*). The diameter of the biopsied lesions ranged from 1 to 10 cm (mean diameter 3.2 cm). Visibility of the needles and precision of the biopsies were evaluated. RESULTS: All interventional biopsies were performed without vascular or organ injuries. Adequate specimens for histologic interpretation were obtained in 42 cases (89.3%). The biopsy results were non-specific in 2 patients (4.2%) and the lesions missed in 3 patients (6.3%). Mean in-room time was 35 minutes and the intervention time was 8.3 minutes. T1-weighted FLASH images proved optimal for confirming needle-tip placement during the biopsies or punctures. Organs, tumors and vessels were easily identified. The FISP sequence proved to be inferior in visualizing vessels and tumors. CONCLUSION: MR-guided liver biopsies are safely and precisely performed using T1-weighted FLASH-sequences with sufficient visualization of the lesions and might be complementary to US- or CT-guided biopsies.

Adult↗

[Transarterial chemoperfusion of inoperable pancreas carcinoma and local recurrence].

BACKGROUND: To evaluate the side effects and tumor response of a locoregional transarterial chemoperfusion with Mitomycin C and Gemcitabine in advanced pancreatic cancer. MATERIALS AND METHODS: Between October 2001 and August 2002, 16 patients were treated in 80 transarterial chemoperfusion sessions with a mean of 5 sessions per patient and a pause of 4 weeks between the sessions. The chemotherapy consisted of a combination of Mitomycin C (8.5 mg/m 2) and Gemcitabine (500 mg/m 2), administered within 1 hour. The tumor response was evaluated by MRT and CT and the quality of life by a patient questionnaire. RESULTS: All patients tolerated the procedure well. The therapeutic outcomes were as follows: in 50 % (n=8) of patients, minor response with a decrease in size of the primary tumor and metastases up to 20 %; in 25 % (n = 4) of patients, stable disease; and in 25 % (n = 4) of patients, progressing metastases with stable primary tumor. Eleven patients (68.75 %) reported a good quality of life without impaired performance of their daily activities. Side effects were moderate and reversible between the treatment cycles. After one year 25 % of the patients were still alive. CONCLUSION: Transarterial chemoperfusion is a minimally invasive treatment for pancreatic carcinomas and local recurrences with little side-effects and can be delivered on an outpatient basis. It might be indicated as potential neoadjuvant treatment before surgery or as palliative treatment to provide clinical benefits and to improve the quality of life.

Activities of Daily Living↗

CT-guided intratumoural administration of cisplatin/epinephrine gel for treatment of malignant liver tumours.

To analyze prospectively the interventional and clinical aspects of computed tomography-guided direct intratumoural injection of a novel chemotherapeutic administration and the parenchymal changes of tumour and necrosis in malignant liver tumours. Eight patients with 17 colorectal liver metastases were treated with a mean of 5.1 injections and nine patients with 13 hepatocellular carcinoma nodules with a mean of 3.1 treatments with computed tomography guided local applications of a novel cisplatin/epinephrine gel. This application provides a higher local and lower systemic drug concentration. Volumes of tumour and necrosis prior and after treatment were measured by computer generated volumetric analysis. Contrast enhanced studies verified pretherapeutic viable tumour volumes with a value of 77.4 ml in the metastases and 29.2 ml in the hepatocellular carcinoma nodules. Intratumoural drug application resulted in a significant increase of necrosis and a decrease in viable tumour volume to be 68.3 ml in metastases and 14.5 ml in hepatocellular carcinoma. Local therapy control rate for the follow up to 6 months was 38 and 71% for the group of metastases and hepatocellular carcinoma, respectively. Direct intratumoural injection of cisplatin/epinephrine injectable gel is a feasible and good tolerated method and results in the development of a statistically significant increase in necrosis in malignant liver tumours. For hepatocellular carcinoma a higher local therapy control rate compared to colorectal metastases can be reported.

Adult↗

[Hepatocellular carcinoma: Role of imaging diagnostics in detection, intervention and follow-up].

PURPOSE: Demonstration of techniques and clinical value of imaging diagnostics for screening, detection, interventional follow-up and therapy control of hepatocellular carcinoma (HCC). Diagnostic techniques for screening, detection and differential diagnosis of HCC are presented using color-coded duplex sonography (US), computer tomography (CT) and contrast-enhanced magnetic resonance techniques like MRI, MR angiography and MR cholangiopancreaticography (MRCP). Therapy control with imaging was performed for surgical methods like resection and liver transplantation as for well as transarterial chemoembolization (TACE), radiofrequency ablation (RF) and laser-induced thermotherapy (LITT). In screening, HCC color-coded duplex sonography reveals a sensitivity from 45 to 92 % and a specificity from 78 to 90 % when liver cirrhosis is present. The diagnostic results of CT were further improved with the newly developed techniques of multislice CT. The highest diagnostic accuracy can currently be achieved using contrast-enhanced MRI with a sensitivity from 82 to 96 %. TACE presents a palliative therapy concept; MR-guided LITT and radiofrequency ablation are used as thermoablative methods for local therapy and the therapy control is based on the above imaging techniques. Contrast-enhanced MRI proves to be the superior imaging technique for the early diagnosis, differential diagnosis and follow-up of hepatocellular carcinoma.

Angiography↗

MR-guided laser-induced thermotherapy of the infratemporal fossa and orbit in malignant chondrosarcoma via a modified technique.

A 76-year-old patient presented with a recurrent mass of a malignant chondrosarcoma in the right infratemporal fossa and in the left maxillary sinus with orbital invasion. The patient was treated with a palliative intention with MR-guided laser-induced thermotherapy using a modified applicator technique. Following treatment clinical symptoms improved and MRI revealed complete laser-induced tumor necrosis.

Aged↗

[Thermal ablation of liver metastases. Current status and prospects].

PURPOSE: To present thermal ablation of liver metastases via laser induced thermotherapy. MATERIAL AND METHODS: Different technical procedures of thermal ablation and online monitoring are used, as there are the MR-guided laser induced thermotherapy (LITT) and the radiofrequency ablation thermotherapy (RF). RESULTS: In a prospective non randomized study 606 patients with liver metastases were treated via MR-guided laser induced thermotherapy. Inclusion criteria were the exclusion of extrahepatic tumor spread and a number of metastases lower than 5 and a size lower than 50 mm in diameter. The local tumor control rate in the 3 month and 6 month control study was 98.3%, the complication rate 3.5% (clinically relevant: 1.2%). The mean survival rate was 40.9 months for all patients with liver metastases without statistically relevant differences for various primaries, like colorectal carcinoma, breast cancer and various other tumors. Results for radiofrequency are so far limited with incidence of a higher local tumor recurrence rate versus LITT. CONCLUSION: MR-guided LITT results in a high local tumor control rate with improved survival.

Adult↗

[Transarterial chemoembolization (TACE) of liver metastases. A palliative therapeutic approach].

Metastatic involvement of the liver determines the treatment. Hepatic artery chemoembolization (TACE) represents a safe palliative treatment for patients with unresectable liver metastases. Technical treatment, indication and results of the TACE are reported. The results of TACE depend on primary cancer, size and vascularisation of the hepatic tumors. Our results with out patient treatment of 245 patients prove that TACE results in a extremely low rate of side effects. Combination of TACE with local ablative treatment may present potentially curative treatment option for unresectable tumors.

Adult↗

[Transarterial chemoembolization in hepatocellular carcinomas: technique, indications, results].

BACKGROUND: At time of diagnosis 80% of the patients with hepatocellular carcinoma (HCC) could not be treated with surgical treatments, so that transarterial chemoembolization (TACE) was used as an neoadjuvant or palliative treatment modality. MATERIAL AND METHODS: 60 patients were treated with 217 TACE courses, in the mean 3.6 TACE treatments per patient with an 4 week interval. TACE was performed with a dispersion of lipiodol, mitomycin C and spherex. 11 patients (18.3%) were treated in a neoadjuvant protocol with successful ablation. Lipiodol retention and size of the tumors were evaluated by CT and MRI. RESULTS: 60 patients were successful treated with TACE. After treatment a primary high lipiodol retention was displayed and in 68 (63.3%) patients a reduction of the tumor size and in 11 (20%) patients a reduction of tumor growth rate was noted. The 1 year survival rate was 59%. After response to TACE and reducing the tumor size 11 patients could be treated with MR-guided LITT 4 to 6 weeks post embolization. CONCLUSION: Chemoembolization is a minimal invasive and outpatient treatment protocol for HCC. TACE might be indicated as a palliative treatment to control the diseased liver. If repeated TACE alters the size and structure of primary unresectable HCC TACE expands the indication for MR-guided LITT.

Adult↗