Biomedical subjects

Katrin Eichler

Publications and source records attributed to Katrin Eichler.

At least 19 recordsLinked to original sources

PubMed2006

Adrenal metastases: CT-guided and MR-thermometry-controlled laser-induced interstitial thermotherapy.

The aim of the study was to evaluate the feasibility, safety and effectiveness of CT-guided and MR-thermometry-controlled laser-induced interstitial thermotherapy (LITT) in adrenal metastases. Nine patients (seven male, two female; average age 65.0 years; range 58.7-75.0 years) with nine unilateral adrenal metastases (mean diameter 4.3 cm) from primaries comprising colorectal carcinoma (n = 5), renal cell carcinoma (n = 1), oesophageal carcinoma (n = 1), carcinoid (n = 1), and hepatocellular carcinoma (n = 1) underwent CT-guided, MR-thermometry-controlled LITT using a 0.5 T MR unit. LITT was performed with an internally irrigated power laser application system with an Nd:YAG laser. A thermosensitive, fast low-angle shot 2D sequence was used for real-time monitoring. Follow-up studies were performed at 24 h and 3 months and, thereafter, at 6-month intervals (median 14 months). All patients tolerated the procedure well under local anaesthesia. No complications occurred. Average number of laser applicators per tumour: 1.9 (range 1-4); mean applied laser energy 33 kJ (range 15.3-94.6 kJ), mean diameter of the laser-induced coagulation necrosis 4.5 cm (range 2.5-7.5 cm). Complete ablation was achieved in seven lesions, verified by MR imaging; progression was detected in two lesions in the follow-up. The preliminary results suggest that CT-guided, MR-thermometry-controlled LITT is a safe, minimally invasive and promising procedure for treating adrenal metastases.

Adrenal Gland Neoplasms↗

PubMed2006

MR-compatible assistance system for punction in a high-field system: device and feasibility of transgluteal biopsies of the prostate gland.

We present the first cadavic study results concerning the feasibility of the use of an MR-guided assistance system, Innomotion (Innomedic, Herxheim, Germany), for accurate and consistent placement of percutaneous needles in the prostate gland. The MR-compatible assistance system consists of a C-arch, guiding arm and application module (AMO). T1-weighted fast low angle shot (FLASH) 2-D-GRE sequence (TR/TE=110/4 ms) and T2-weighted turbo spin-echo (TSE)-sequences (TR/TE=3200/97 ms) in transversal orientation were used for the monitoring of the punction of the prostate gland. Planning and control of the intervention is to be made outside the scanner room on a desktop computer that receives DICOM images from the scanner. Servopneumatic drives move the AMO to the insertion point. The physician has to introduce the punction needle manually. The mean deviation of the needle tip to the target in a gel phantom was 0.35 mm. An accurate punction of the prostate gland can easily be performed using this system with a transgluteal access. The T2-weighted images are superior for the evaluation of the prostate anatomy and the needle position during the interventions. In conclusion, our preliminary results indicate that this MR-guided assistance system is suitable for an accurate transgluteal needle placement in the prostate.

Automation↗

PubMed2006

Preliminary experience with transarterial chemoembolization (TACE) in liver metastases of uveal malignant melanoma: local tumor control and survival.

PURPOSE: To evaluate results in the palliative treatment of patients with liver metastases of uveal malignant melanoma using transarterial chemoembolization (TACE). MATERIALS AND METHODS: Superselective TACE was repeatedly performed in 12 patients with liver metastases of uveal malignant melanoma. Six patients presented with solitary liver metastases (6-12 cm in size) and six patients with oligonodular metastases (n < or = 6). The embolization suspension consisted of a maximum of 10 mg/m(2) Mitomycin C, 10 ml Lipiodol, and an injection of 200-450 mg resorbable microspheres for vascular occlusion. In the follow-up, magnetic resonance imaging was performed in 3-month intervals. RESULTS: The TACE procedure was well tolerated in all patients without any relevant side effects. Three patients responded to TACE with a size reduction of more than 50% (partial response), five patients with stable disease, and four patients with progressive disease with an increase in volume of more than 25%. Mean survival following primary tumor treatment was 32.9 months, and after first embolization 19.5 months. Lower survival rates were recorded for the progressive group (16.5 months). CONCLUSION: Repeated TACE offers a palliative treatment option in patients with oligonodular liver metastases of uveal malignant melanoma.

Adult↗

PubMed2006

Colorectal liver metastases: regional chemotherapy via transarterial chemoembolization (TACE) and hepatic chemoperfusion: an update.

Liver metastasis is one of the main problems encountered in colorectal cancer management as the liver is the most common metastatic site. Several treatment options are available, among which transarterial chemotherapy has proved effective in achieving some local tumour control, improving the quality of life through symptomatic control as well as survival time. The present paper is intended to provide an overview of the techniques, indications and results of regional chemotherapy, which comprises transarterial chemoembolization (TACE) and chemoperfusion. This treatment approach has symptomatic, palliative, adjuvant and potentially curative objectives. We reviewed the studies involving TACE and chemoperfusion of colorectal liver metastases during the last few years to update the previous reviews published on this subject. The results achieved were so variable, due to the variations in patient selection criteria and regimens used between the different studies. The median survival ranged from 9 to 62 months and the morphological response ranged from 14 to 76%. Technical aspects, results, and complications of this modality will be demonstrated with a detailed analysis and comments.

Chemoembolization, Therapeutic↗

PubMed2006

Large-sized hepatocellular carcinoma (HCC): a neoadjuvant treatment protocol with repetitive transarterial chemoembolization (TACE) before percutaneous MR-guided laser-induced thermotherapy (LITT).

This study aims to evaluate the efficacy and safety of a neoadjuvant treatment protocol with repeated transarterial chemoembolization (TACE) before MR-guided laser-induced thermotherapy (LITT) for large-sized hepatocellular carcinomas (HCC). Repeated TACE (mean, 3.5 treatments per patient) was performed in 48 patients with neoadjuvant intention (the largest lesion was between 50 and 80 mm in diameter, and there were no more than five lesions). For the TACE treatment, we used 10 mg/m(2) mitomycin, 10 ml/m(2) Lipiodol and microspheres. The tumor volume was measured by MRI. Lipiodol retention of the tumors was evaluated with CT. After the diameter of the tumors had decreased to less than 50 mm, the patients were treated with MR-guided LITT 4 to 6 weeks after embolization. Repeated TACE reduced the tumor size in 32 patients (66.7%), forming the basis for performing MR-guided LITT procedures. These patients received one to four laser treatments (mean, 1.9 per patient) for tumor ablation, resulting in a median survival of 36.0 months after the first treatment. For the remaining patients, no reduction in tumor size was achieved in 12 patients and disease progression in 4 patients. Neoadjuvant TACE appears to be an effective treatment of large-sized HCC, which extends the indication for MR-guided LITT.

Aged↗

PubMed2006

Hepatic intraarterial chemotherapy with gemcitabine in patients with unresectable cholangiocarcinomas and liver metastases of pancreatic cancer: a clinical study on maximum tolerable dose and treatment efficacy.

PURPOSE: To define the maximum tolerated dose (MTD) of hepatic intraarterial chemotherapy with gemcitabine, administered with and without starch microspheres, in patients with inoperable intrahepatic cholangiocarcinomas and liver metastases of pancreatic carcinomas. METHODS: Gemcitabine was administered on days 1 and 8 with intervals of 2 weeks between the cycles. In group A the initial gemcitabine dose of 1,000 mg/m(2) (without microspheres) was increased in 200-mg/m(2) steps up to a maximum dose of 2,000 mg/m(2). In group B the MTD with microspheres was assessed by giving an additional microsphere dose according to tumor extent and body weight, increasing gemcitabine starting from a dose-step below the MTD with microspheres. The MTD was evaluated via clinical and laboratory findings. RESULTS: Twenty-four patients were enrolled (12 males, 12 females, mean age 59.17 years; intrahepatic cholangiocarcinoma: n = 17, liver metastases of pancreatic carcinoma: n = 7). The MTD of gemcitabine without microspheres was reached at 1,400 mg/m(2), and of gemcitabine with microspheres at 1,800 mg/m(2). The comparative evaluation revealed statistically significant better data for the time to progression (p < 0.01) and survival for the group with microspheres (6.8 and 20.2 months) in comparison to the group without microspheres (4.2 and 13.5 months). CONCLUSION: This clinical study indicates that the intraarterial application of gemcitabine with doses higher than the recommended 1,000 mg/m(2) is well tolerated if combined with microspheres, and yields respectable results in patients who do not respond to systemic chemotherapy.

Adenocarcinoma↗

PubMed2006

Postinterventional percutaneous closure of femoral artery access sites using the Clo-Sur PAD device: initial findings.

The purpose of this study was to evaluate a percutaneous hemostatic device in patients to achieve immediate hemostasis at the vascular access site as well as early ambulation after vascular interventional procedures. In a randomized trial, a hemostatic device (Clo-Sur PAD, Medtronic AVE, Inc., Santa Rosa, CA, USA; n=60) was compared with manual compression (n=60) in patients after endoluminal intervention through an inguinal access (sheath sizes: 5-7 French). Device safety was evaluated by assessing complications within 24 h and 14 days. System efficacy was measured by the percentage of achieved immediate hemostasis and early ambulation. Device application was possible in 57 cases (95.0%), with 93.3% (56/60) of the patients rising 2 h after application. Hemostasis time was 10.15+/-1.96 min (control group: 16.20+/-1.79 min), with a pressure bandage time of 3.47+/-5.53 h (control group: 13.8+/-4.32 h). Ambulation was possible after 2.13+/-0.50 h (control group: 8.57+/-3.47 h). Complications encountered were access-site bleeding with hematoma (device: n=3; control: n=9). All complications were managed conventionally without blood transfusion or surgical intervention. The system is an easy to use device permitting early ambulation without additional pressure bandaging in the majority of patients. Preliminary data show that hemostasis does not depend on the level of anticoagulation.

Aged↗

PubMed2006

Effect of laser-induced thermotherapy on liver metastases.

Laser-induced thermotherapy, or laser ablation, is an established minimally invasive percutaneous technique of tumor ablation. It is performed routinely in hepatic tumors and in other indications. Most patients treated with laser-induced thermotherapy suffer from liver metastases from primary tumors, particularly colorectal cancer. In this review, the local control rate, including morphological response and local recurrence, is evaluated. Survival data, including median survival time and 1-, 2- and 3-year survival, are discussed; treatment complications are also explored. The method of treatment performance and evaluation, results, and the authors' views on the current status of treatment are outlined.

Contraindications↗

PubMed2005

MR-guided biopsies with a newly designed cordless coil in an open low-field system: initial findings.

The purpose of this study was to examine the feasibility and safety of MR-guided biopsies with a newly designed cordless coil in an open low-field magnetic resonance (MR) system. Eleven patients were biopsied using a low-field system (0.2 T, Magnetom Concerto, Siemens) by using the new cordless coil (Siemens). The biopsies were performed in different organ systems [liver (n = 7), abdomen (n = 1), shoulder (n = 1), pelvis (n = 1) and hip (n = 1)]. The procedures were guided using T1-weighted FLASH (fast low-angle shot) sequences. The lesions were biopsied using the coaxial technique through a 15-gauge puncture needle with a 16-gauge biopsy handy. Coil handling, image quality and complications were evaluated. Imaging quality and visualization of the lesions were optimal up to a penetration depth of 9 cm. In all cases the biopsy procedures were successfully performed with MR guidance without any complications. Pathological findings revealed seven cases of malignant tissue and four cases of non-malignant tissue. The use of the cordless coil allows improved patient access during the biopsy and an improved handling of the coil system. MR-guided biopsy using the novel cordless coil system can be performed safely and precisely with easy handling of the coil. This coil concept, however, is restricted to special indications.

Aged↗

PubMed2005

MR-guided laser ablation.

MR-guided LITT is a safe and effective treatment modality that improves survival in well-selected patients who have liver metastases. A major advantage of MR-guided LITT is that it can be easily performed under local anesthesia in an outpatient setting with a low complication rate.

Adolescent↗

PubMed2004

Breast cancer metastases in liver: laser-induced interstitial thermotherapy--local tumor control rate and survival data.

PURPOSE: To evaluate the local tumor control rate and survival data for magnetic resonance (MR) imaging-guided laser ablation of breast cancer liver metastases by using laser-induced interstitial thermotherapy (LITT). MATERIALS AND METHODS: MR-guided LITT was performed in 232 female patients with 578 liver metastases from breast cancer. Survival rates were calculated with the Kaplan-Meier method. Indications for the procedure were defined for patients with no more than five metastases, none of which were larger than 5 cm in diameter, as follows: recurrent liver metastases after partial liver resection (8.2%), metastases in both liver lobes (45.2%), locally nonresectable tumors (19%), general contraindications for surgery (2.6%), or refusal to undergo surgical resection (25%). RESULTS: Local recurrence rate at 6-month follow-up after LITT was 2.3% (five of 213) for metastases up to 2 cm in diameter, 4.3% (seven of 162) for metastases 2-3 cm in diameter, 3.2% (two of 63) for metastases 3-4 cm in diameter, and 1.9% (one of 52) for metastases larger than 4 cm in diameter. No additional local tumor progression was observed beyond 6 months. The mean survival rate for all treated patients, with calculation started on the date of diagnosis of the metastases treated with LITT, was 4.9 years (95% confidence interval: 4.3, 5.4). The median survival was 4.3 years; 1-year survival, 96%; 2-year survival, 80%; 3-year survival, 63%; and 5-year survival, 41%. The mean survival after the first LITT treatment was 4.2 years (95% confidence interval: 3.6, 4.8). CONCLUSION: MR-guided LITT yields high local tumor control and survival rates in patients with liver metastases from breast cancer.

Adult↗

PubMed2004

MR-guided transgluteal biopsies with an open low-field system in patients with clinically suspected prostate cancer: technique and preliminary results.

The purpose of this study was to examine the feasibility and safety of MR-guided biopsies with a transgluteal approach in patients with uncertain or suspicious prostate lesions. Twenty-five patients with uncertain or suspicious focal prostate lesions detected by high-field MR imaging of the prostate gland using endorectal coil imaging were biopsied with a transgluteal approach in a low-field MRI system (0.2 T, Concerto, Siemens). The procedures were guided using T1-weighted FLASH sequences. The prostate gland was biopsied repeatedly with a coaxial technique through a 15-gauge pencil tip with a 16-gauge biopsy handy (median 3.8 samples per patient). Complications and biopsy findings were documented retrospectively. Using T1-weighted sequences biopsy procedures were performed successfully with MR guidance in all cases without any side effects or complications. The median intervention time was 11.3 min. Pathological findings revealed ten cases of hyperplasia or atrophy, three cases of prostatitis, ten cases of carcinoma and two cases of normal tissue. The clinical follow-up showed that in two patients prostate cancer was missed at MR-guided biopsy. Transgluteal MR-guided biopsy of the prostate gland is a safe and promising approach for histological clarification of uncertain or suspicious lesions.

Aged↗

PubMed2004

Interstitial photodynamic laser therapy in interventional oncology.

Photodynamic therapy (PDT) is a well-investigated locoregional cancer treatment in which a systemically administered photosensitizer is activated locally by illuminating the diseased tissue with light of a suitable wavelength. PDT offers various treatment strategies in oncology, especially palliative ones. This article focuses on the development and evaluation of interstitial PDT for the treatment of solid tumors, particularly liver tumors. The PDT is mostly used for superficial and endoluminal lesions like skin or bladder malignancies and also more frequently applied for the treatment of lung, esophageal, and head and neck cancer. With the help of specially designed application systems, PDT is now becoming a practicable option for solid lesions, including those in parenchymal organs such as the liver. After intravenous treatment with the photosensitizer followed by interstitial light activation, contrast-enhanced computed tomography shows the development of therapy-induced necrosis around the light-guiding device. With the use of multiple devices, ablation of liver tumors seems to be possible, and no severe side effects or toxicities related to the treatment are reported. PDT can become a clinically relevant adjunct in the locoregional therapy strategies.

Humans↗

PubMed2003

Colorectal carcinoma metastases in liver: laser-induced interstitial thermotherapy--local tumor control rate and survival data.

PURPOSE: To evaluate the local tumor control and survival data for magnetic resonance (MR) imaging-guided laser-induced interstitial thermotherapy (LITT) of colorectal liver metastases. MATERIALS AND METHODS: MR imaging-guided LITT was performed in 603 patients (mean age, 61.2 years) with 1,801 liver metastases of colorectal cancer. Survival rates were calculated by means of the Kaplan-Meier method. Local tumor control and tumor volume were evaluated with nonenhanced and contrast material-enhanced MR imaging. Indications for the procedure were defined for patients with five or fewer metastases, none of which were larger than 5 cm in diameter. The indications included recurrent liver metastases after partial liver resection in 37.6% of study patients, metastases in both liver lobes in 32.5%, locally nonresectable lesions in 11.3%, general contraindications for surgery in 4.6%, and refusal to undergo surgical resection in 13.9%. RESULTS: Local recurrence rate at 6-month follow-up was 1.9% (nine of 474) for metastases up to 2 cm in diameter, 2.4% (13 of 539) for metastases 2.1-3.0 cm in diameter, 1.2% (four of 327) for metastases 3.1-4.0 cm in diameter, and 4.4% (13 of 294) for metastases larger than 4 cm in diameter. The mean survival rate for all treated patients, with calculation started on the date of diagnosis of the metastases (which were treated with LITT) was 4.4 years (95% CI: 4.0, 4.8) (1-year survival, 94%; 2-year survival, 77%; 3-year survival, 56%; 5-year survival, 37%). Median survival was 3.5 years (95% CI: 3.0, 3.9). Mean survival after the first LITT treatment was 3.8 years (95% CI: 3.4, 4.2). Median survival was 2.9 years (95% CI: 2.4, 3.3). CONCLUSION: MR imaging-guided LITT yields high local tumor control and survival rates in well-selected patients with limited liver metastases of colorectal carcinoma.

Adult↗

PubMed2003

Liver metastases: neoadjuvant downsizing with transarterial chemoembolization before laser-induced thermotherapy.

PURPOSE: To evaluate a treatment protocol with repeated transarterial chemoembolization (TACE) before laser-induced thermotherapy (LITT) in patients with unresectable liver metastases that are too large for LITT alone. MATERIALS AND METHODS: One hundred sixty-two patients who had unresectable liver metastases, with the largest lesion as large as 80 mm in diameter, and no more than four lesions were treated with repeated TACE between March 1999 and December 2001. TACE was performed with a maximum of 10 mg/m2 mitomycin for chemotherapy and a maximum of 15 mL/m2 of iodized oil and microspheres for vessel occlusion. Tumor volume before and during treatment was measured at magnetic resonance (MR) imaging. If the diameter of the tumor decreased to less than 50 mm, the patients were treated with MR imaging-guided LITT 4-6 weeks following embolization. RESULTS: Eighty-two patients (62 with metastases from colorectal cancer, 14 with metastases from breast cancer, and six with metastases from other primary tumors) responded to TACE, with a mean reduction in tumor size of 35% +/- 14 (SD), and were treated with LITT. Each patient underwent two to seven TACE treatments (mean, 4.3) prior to LITT. In 47 patients, no reduction in tumor size was achieved, which led to further follow-up. In 33 patients, disease progression was found, with either an increasing size of the lesions (n = 18) or newly developing metastases (n = 15), and these results led to further TACE treatments or change to systemic chemotherapy. Median survival of patients who responded to this combined treatment was 26.2 months; in patients treated with only TACE, median survival was 12.8 months (range, 0.3-29.4 months). CONCLUSION: With repeated TACE, reduction in size of primary unresectable hepatic metastases is achieved in 50.6% of cases and allows local ablative treatments such as MR imaging-guided LITT.

Adult↗

PubMed2002

MR-guided laser-induced thermotherapy with a cooled power laser system: a case report of a patient with a recurrent carcinoid metastasis in the breast.

We report a case of a 52-year-old woman with a palpable recurrent metastasis of a neuroendocrine carcinoma to the upper outer quadrant of the right breast. For the treatment of this lesion, MR-guided laser-induced thermotherapy was performed with a cooled power laser system (Nd:YAG-Laser). An open 0.2-T MR unit was used for the monitoring of the laser energy delivery to the breast; thus, a thermosensitive fast low-angle shot 2D sequence for MR thermometry was used, so the ablation of the tumor and the increase of laser-induced necrosis could be interactively visualized with the repetitive use of this sequence. The postinterventional MR control exams 1 day and 4 months after laser-induced thermotherapy at the 1.5-T MR unit (Magnetom Symphony Quantum, Siemens, Erlangen, Germany) verified the complete ablation of the tumor without any signs of residual or relapsing tumor.

Breast Neoplasms↗

PubMed2002

Superparamagnetic iron oxide-enhanced MR imaging of head and neck lymph nodes.

PURPOSE: To compare findings on superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) images of the head and neck with those from resected lymph node specimens and to determine the effect of such imaging on surgical planning in patients with histopathologically proved squamous cell carcinoma of the head and neck. MATERIALS AND METHODS: Thirty patients underwent MR imaging with nonenhanced and SPIO-enhanced (2.6 mg Fe/kg intravenously) T1-weighted (500/15 [repetition time msec/echo time msec]) and T2-weighted (1,900/80) spin-echo and T2-weighted gradient-echo (GRE) (500/15, 15 degrees flip angle) sequences. Signal intensity decrease was measured, and visual analysis was performed. Surgical plans were modified, if necessary, according to MR findings. Histopathologic and MR findings were compared. RESULTS: Histopathologic evaluation of 1,029 lymph nodes revealed 69 were metastatic. MR imaging enabled detection of 59 metastases. Regarding lymph node levels, MR diagnosis was correct in 26 of 27 patients who underwent surgery: Only one metastasis was localized in level II with MR imaging, whereas histopathologic evaluation placed it at level III. Extent of surgery was changed in seven patients. SPIO-enhanced T2-weighted GRE was the best sequence for differentiating between benign and malignant lymph nodes. CONCLUSION: SPIO-enhanced MR imaging has an important effect on planning the extent of surgery. On a patient basis, SPIO-enhanced MR images compared well with resected specimens.

Adult↗

PubMed2002

Malignant liver tumors treated with MR imaging-guided laser-induced thermotherapy: experience with complications in 899 patients (2,520 lesions).

PURPOSE: To evaluate the complications from laser-induced thermotherapy (LITT) of malignant liver tumors and demonstrate that LITT is safe as an outpatient procedure. MATERIALS AND METHODS: During 8 years, 899 patients with malignant liver tumors were treated with magnetic resonance (MR) imaging-guided LITT. A total of 2,132 LITT procedures were performed to treat 2,520 lesions. To account for the technical evolution of LITT during this time and the change from performing the procedure on an inpatient basis to performing it on an outpatient basis, patients were assigned to four groups. Overall complication rates and major and minor complications in the inpatient versus outpatient groups were evaluated. Multidimensional contingency table analysis with the chi(2) test was performed. RESULTS: On the basis of a total of 2,132 LITT procedures performed, complications were divided into major and minor categories and detected at clinical or imaging studies. Major complications included three deaths (0.1%) within 30 days after LITT, pleural effusion requiring thoracentesis in 16 (0.8%) cases, hepatic abscess requiring drainage in 15 (0.7%) cases, bile duct injury in four (0.2%) cases, segmental infarction in three (0.1%) cases, and hemorrhage requiring transfusion in one (0.05%) case. Minor complications included postprocedural fever in 710 (33.3%), pleural effusion not requiring thoracentesis in 155 (7.3%), subcapsular hematoma in 69 (3.2%), subcutaneous hematoma in 24 (1.1%), pneumothorax in seven (0.3%), and hemorrhage in two (0.1%) cases. Outpatient management did not significantly affect pleural effusion (P =.96) or subcapsular hematoma (P =.33) rate. CONCLUSION: MR imaging-guided LITT with local anesthesia is safe and yields an acceptably low rate of major complications.

Ambulatory Care↗