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M Forsting

Publications and source records attributed to M Forsting.

At least 19 recordsLinked to original sources
PubMed2007

[Comparison of unidimensional and bidimensional measurement to assess therapeutic response in the treatment of solid tumors].

PURPOSE: In this prospective study we applied both the bidimensional WHO method and the unidimensional RECIST method in treatment follow-up of solid tumors. MATERIAL AND METHODS: Computed tomography was performed in 80 patients before and after one chemotherapy cycle: 20 patients each with lung cancer, lymphoma, and metastases of the lung and the liver. In 207 tumor lesions unidimensional and bidimensional measurements were performed: 36 lesions of lung cancer, 51 lesions of lymphoma, and 60 lesions of metastases of the lung and the liver, respectively. We assigned the results to the corresponding response categories. RESULTS: For tumor assessment, the kappa statistic produced a high agreement of 0.94 between the two methods for assessment of therapeutic response. CONCLUSION: The unidimensional RECIST measurement is easier to perform in order to assess tumor size during treatment follow-up in oncologic radiology.

Adult↗
PubMed2007

[Liver biopsy under guidance of multislice computed tomography: comparison of 16G and 18G biopsy needles].

BACKGROUND: Percutaneous cutting needle biopsy of focal liver lesions under CT guidance has established itself as a standard method. The purpose of this study was to evaluate which diagnostic quality can be achieved under guidance of multislice CT (MSCT) and with the use of different needle sizes. METHODS: The data of 163 MSCT-guided core biopsies of focal liver lesions were evaluated. A 16G biopsy needle was used in 121 cases and an 18G needle in 42 cases. RESULTS: The sensitivity, specificity, and accuracy for all biopsies were 93.3, 100.0, and 94.5%. The corresponding values were 97.2, 100.0, and 97.5% for the 16G needle and 78.6, 100.0, and 85.7% for the 18G needle, respectively. A definite histological diagnosis could be obtained in 90.0% of the cases (16G 94.0%, 18G 75.8%). These differences were statistically highly significant. Bleeding complications were recognized in seven biopsies (4.3%). In one patient a fatal bleeding occurred after the biopsy. Median biopsy duration was 27 min. CONCLUSIONS: Core biopsy under MSCT guidance is a fast and very accurate method to obtain a histological diagnosis in focal liver lesions. The usage of a 16G needle in comparison to an 18G needle yielded a significantly higher rate of correct results with regard to differentiation between benign and malignant disease as well as establishing a definite histological diagnosis. For an accurate diagnosis of liver lesions a 16G needle is recommended. After biopsy, the patients have to be closely monitored.

Aged↗
PubMed2006

Evaluation of quantitative parametric analysis for characterization of breast lesions in contrast-enhanced MR mammography.

Our aim was to evaluate quantitative parametric analysis for characterization of breast lesions in contrast-enhanced magnetic resonance (MR) mammography. In 62 patients, contrast-enhanced MR mammography revealed 75 suspicious lesions, of which 18 were benign and 57 were malignant. The quantitative parametric analysis delineates signal intensity changes of contrast-enhanced lesions on a pixel-by-pixel basis. The initial rate of enhancement is coded by color intensity: a slow rate is coded to dark; a fast rate, bright. The postinitial enhancement change is coded by color hue: blue for increasing signal intensity, green for plateau, and red for decrease in signal intensity. Malignant lesions showed a significantly higher number of bright-red (P = 0.004) and medium-red (P < 0.001) pixels than benign lesions. Benign lesions showed significantly more blue pixels than did malignant lesions (P = 0.010). Of the 75 lesions, 72 (96%) showed heterogeneous distribution of pixel color hue. Quantitative parametric analysis of contrast kinetics in lesions can replace the subjective manual region of interest (ROI) method and makes a step toward standardization of MR mammography. It allows quantitative evaluation of different contrast kinetics parameters in contrast-enhanced breast lesions.

Adult↗
PubMed2006

[Endovascular therapy for intracranial aneurysms].

During the past 5 to 10 years, therapy for aneurysms has seen dramatic changes. In some centers they happened before the ISAT study, in others afterward. Endovascular treatment is now the method of choice for intracranial aneurysms whenever possible. Large centers are using it for 70-80% of aneurysms. Due to constant development of new interventional materials, even wide-necked aneurysms in practically all localizations can be treated today with very dependable results. The remaining aneurysms are quite difficult to treat and represent a great neurosurgical challenge. Despite all the technical improvements, closure is still not the most difficult element of the therapeutic procedure. This role is played by the subarachnoidal hemorrhage, which still is decisive for patient outcome. All related disciplines are urgently called upon to solve the unresolved problems as quickly and efficiently as possible through determined research.

Anticoagulants↗
PubMed2006

[MR Imaging of the pelvis in the diagnosis of the endometrium in breast cancer patients in tamoxifen therapy].

PURPOSE: The purpose of the study was to determine the value of MR imaging of the pelvis in the diagnostic work-up of the endometrium in breast cancer patients in tamoxifen therapy. MATERIALS AND METHODS: MR imaging of the pelvis was performed on 24 patients (mean: 62 years, range: 51 - 74 years) and 30 healthy women (mean: 65 years, range: 51 - 73 years). The volume of the uterus and cervix and the maximal thickness of the endometrium, junctional zone and myometrium of the uterus were determined and compared to the confidence interval of the parameters in healthy women. The Mann-Whitney U-test was used to identify differences in the volume of the uterus and cervix and in the thickness of the uterine wall layers in both groups. RESULTS: A comparison of the volume of the uterus and cervix and the thickness of the uterine wall layers in the two groups yielded no significant differences. The volume of the uterus and cervix showed no statistical differences between the two groups. The maximal height of the endometrium in the patient group showed a mean of 0.6 cm (range: 0.1 - 2.2 cm), and a mean of 0.4 cm (range: 0.1 - 1.2 cm) in the group of healthy women. The differences were not statistically significant. In all healthy women the endometrium showed homogeneous signal intensity in the sagittal T2-weighted images. In 12 of the 24 breast cancer patients, the endometrium showed inhomogeneous signal intensity. In 9 of 12 patients with an inhomogeneous endometrium with a thickness equal to or greater than 0.6 cm, histopathology confirmed polyps. In 3 patients endometrium hyperplasia was found. In one patient histopathology revealed a polyp and an endometrium carcinoma in stage T1 a N0. The endometrium carcinoma was not able to be seen via MR imaging. CONCLUSION: MR imaging might be helpful in the diagnosis of endometrium pathologies during tamoxifen therapy. Therefore, MR imaging of the pelvis could be used as a diagnostic tool in the follow-up diagnosis of the endometrium in breast cancer patients in tamoxifen therapy.

Adenocarcinoma↗
PubMed2006

Hypopituitarism following severe traumatic brain injury.

Although hypopituitarism is a known complication of traumatic head injury, it may be under-recognized due to its subtle clinical manifestations. To address this issue, we determine the prevalence of neuroendocrine abnormalities in patients rehabilitating from severe traumatic brain injury (Glasgow Coma Scale < or = 8). 76 patients (mean age 39 +/- 14 yr; range 18-65; 53 males and 23 females; BMI 25.8 +/- 4.2 kg/m2; mean +/- SD) with a severe traumatic brain injury, an average of 22 +/- 10 months before this study (median, 20 months), underwent a series of standard endocrine tests, including TSH, free T4, T4, T3, prolactin, testosterone (males), estradiol (females), cortisol, ACTH, GH, and IGF-I. All subjects also underwent GH response to GHRH + arginine. Growth hormone deficiency (GHD) was defined as a GH response < 9 microg/L to GHRH + arginine and was confirmed by ITT (< 3 microg/L). Pituitary deficiency was shown in 24% of the patients (18/76). 8% (n = 6) had GHD (GH-peak range [GHRH + arginine]: 2.8-6.3 microg/L; GH-peak range [ITT]: 1.5-2.2 microg/L; IGF-I range: 62-174 microg/L). 17% (n = 13) had hypogonadism (total testosterone < 9.5 nmol/L and low gonadotropins in 12 males; low estradiol, and low gonadotropins in 1 female). Total testosterone levels did not correlate with BMI or age. 2 males with hypogonadism also showed a mild hyperprolactinemia (33 and 41 ng/ml). 3% (n = 2) patients had partial ACTH-deficiency (cortisol-peak [ITT] 392 and 417 nmol/L) and 3% (n = 2) had TSH-deficiency. In summary, we have found hypopituitarism in one-fourth of patients with predominantly secondary hypogonadism and GHD. These findings strongly suggest that patients who suffer head trauma must routinely include neuroendocrine evaluations.

Adolescent↗
PubMed2006

[Angiographic follow-up after carotid artery stenting of bifurcation stenosis].

PURPOSE: The purpose of this prospective study was to determine the restenosis grade, the intima hyperplasia and the stent expansion via angiographic follow-up six months after carotid artery stenting. MATERIALS AND METHODS: In 100 patients, angiographic follow-up was performed 5.9 months (range: 2.9-11.4 months) after carotid artery stenting. The restenosis grade, the intima hyperplasia and the stent expansion were measured by selective angiography of the treated carotid artery. RESULTS: The mean restenosis grade was 16 % (range: 0-78 %). In 6 of 100 patients (6 %), a restenosis grade of > 50 % was measured. In 4 patients the restenosis grade was 50-70 %. In 2 patients the restenosis grade was > 70 %. In 91 of 100 patients (91 %), the restenosis was localized in the former area of stenosis of the carotid artery, and in 9 of 100 patients (9 %), the restenosis was localized in the cranial stent end. The mean grade of intima hyperplasia was 31 % (range: 2-70 %). The mean increase in stent expansion at the time of follow-up was 10 % (range: 0-59 %). No correlation was able to be determined between the grade of stenosis and the grade of restenosis (rho = 0.017, range: - 0.180-0.213), between the grade of residual stenosis and the grade of restenosis (rho = 0.257, range: 0.064-0.431) and between intima hyperplasia and the grade of restenosis (rho = 0.476, range: 0.309-0.615). CONCLUSIONS: Carotid artery stenting is associated with a low incidence of high-grade restenosis 6 months after an intervention. The intima hyperplasia, which can be observed in each Wallstent, is partly compensated by the expansion of the self-expandable stent. Without a correlation between the grade of residual stenosis and the grade of restenosis, low-grade residual stenosis can be accepted. Therefore, we recommend undersized postdilation of the Wallstent.

Aged↗
PubMed2006

[Whole-body MR diagnostic concepts].

The term whole-body magnetic resonance imaging (MRI) covers a whole series of different MRI techniques that can be used for detecting various diseases. Whole-body magnetic resonance angiography facilitates the visualization of the entire arterial system from head to toe with the exception of the coronary arteries. Whole-body MRA is clinically used for therapy planning in patients with multiple stenoses and may be able to be used in the future as a screening method for high risk populations, for example in patients with coronary heart disease. Whole-body MRI can replace skeletal scintigraphy in the detection of bone marrow metastases by using fluid-sensitive sequences. Fast contrast-enhanced sequences can be used as an alternative approach in the search for tumors. Whole-body MRI can even be superior to a combination of positron-emission tomography and computed tomography in the detection of distant metastases. This article presents the recent developments in whole-body MRI and its established indications, which in the future might lead to a change in the paradigm for the diagnostic work-up of many diseases.

Humans↗
PubMed2006

[Radiofrequency ablation of malignant liver tumors: use of a volumetric necrosis-tumor ratio for local control].

PURPOSE: Sufficient safety margins are essential for preventing local tumor recurrence after radiofrequency ablation RFA of malignant liver tumors. The aim was to determine the initial tumor volume, ablation necrosis volume, and the necrosis-tumor quotient in order to compare these parameters with the rate of local control during follow-up. MATERIALS AND METHODS: 35 patients with 53 tumor nodules (29 colorectal metastases and 24 HCC nodules) were enrolled. RFA procedures were performed under CT guidance with intravenous conscious sedation. Tumor volumes were measured based on CT data sets and the necrosis volume was assessed using the sum-of-area method. A volumetric necrosis/tumor quotient (NTQ) was calculated for all lesions. Follow-up examinations were performed after 3, 6, and 12 months and then on a yearly basis to identify local recurrent tumors. RESULTS: The CRC metastases and HCC nodules had a median tumor volume of 8.3 ml and 7.4 ml, respectively. The mean ablation volumes were 37.6 ml and 29.5 ml, respectively. This resulted in a median NTQ of 3.9 for metastases and 3.4 for HCC. The follow-up (mean time 18 months) revealed local tumor recurrence in 16 of 29 (55 %) metastases and 10 of 24 (42 %) HCC nodules. In lesions with local recurrence, the initial tumor volume was significantly greater and the NTQ was significantly smaller. A threshold value of 3.4 for NTQ has the highest predictive value for local tumor recurrence. CONCLUSION: The volumetric necrosis/tumor quotient NTQ makes it possible to predict the local outcome and can be used for the planning of additional therapy.

Aged↗
PubMed2006

Magnetic resonance imaging of the ovaries of healthy women: determination of normal values.

PURPOSE: To establish normal values for the volume and maximal diameter of ovaries and ovarian follicles and for the number of ovarian follicles in magnetic resonance imaging (MRI) based on menstrual cycle phase and age. MATERIAL AND METHODS: We performed MRI of the pelvis on 100 healthy women. Volume of the ovaries and largest ovarian follicles and the number of ovarian follicles were determined by menstrual cycle phase and age. RESULTS: The mean volume of the ovaries significantly increased with age and reached its peak between 31 and 40 years, and subsequently decreased. The mean volume of the largest ovarian follicles also significantly increased with age to reach its peak at 41-50 years. The highest mean numbers of ovarian follicles were found at 20-40 years. When the volumes of ovaries and of the largest ovarian follicles, and the number of ovarian follicles were compared between the first and second phase of the menstrual cycle, no significant differences were found. CONCLUSION: The volume and maximal diameter of ovaries and ovarian follicles and the number of ovarian follicles differ significantly with age, but not between the two phases of the menstrual cycle. Knowledge of MRI-related normal values can be expected to aid the early identification of ovarian pathologies.

Adult↗
PubMed2006

Endovascular treatment of middle cerebral artery aneurysms with electrolytically detachable coils.

BACKGROUND AND PURPOSE: Middle cerebral artery (MCA) aneurysms often have an unfavorable aneurysm geometry that might limit endovascular therapy. Our purpose was to analyze the feasibility, safety, and efficacy of coil embolization in a consecutive series of MCA aneurysms chosen for endovascular treatment. PATIENTS AND TECHNIQUES: Of 235 MCA aneurysms seen at our institution during the past 5 years, 36 patients harboring 38 MCA aneurysms were primarily selected for coil embolization: 18 patients had an acute subarachnoid hemorrhage (SAH), 16 of which were due to a ruptured MCA aneurysm. SAH was classified according to Hunt and Hess grade: I (5), II (7), III (5), IV (0), and V (1). RESULTS: Complete occlusion could be achieved in 33 of 38 aneurysms. In 5 aneurysms, coil embolization was not performed because of an unfavorable aneurysm geometry with a wide neck or incorporation of adjacent branches (3) or failed because of insecure coil placement (1) or severe vasospasm (1). Procedural complications included coil protrusion into the parent artery (1), and thromboembolic M2 occlusion (5), with recanalization in 4 of 5 cases. Of 8 aneurysms with initial subtotal occlusion, 3 progressed to total occlusion during follow-up. Three aneurysms had to be retreated, and no patient rebled. Glasgow Outcome Scale at 6 months for the patients with SAH (17/18) was good recovery (12), moderate disability (4), severe disability (0), persistent vegetative state (0), and death (1); outcomes for patients with an incidental aneurysm (17/18) were good recovery (16) and moderate disability (1). CONCLUSION: Endovascular coil embolization can be performed safely and effectively in selected MCA aneurysms. Initial subtotal aneurysm occlusion might progress to total occlusion.

Adult↗
PubMed2005

Neural substrates of manipulation in visuospatial working memory.

The present study aimed to investigate in humans whether similar neuronal mechanisms underlie the manipulation and active processing of visual and visuospatial stimuli. Simultaneous and successive mental rotation and identity judgment of 2-D matrices and 3-D cube figures were contrasted using functional magnetic resonance imaging (fMRI). Results demonstrate that activation patterns during mental rotation with low working memory demands differ depending on stimulus type (2-D vs. 3-D). Comparison of simultaneous mental rotation of matrices and 3-D cubes resulted in activation of frontal as well as inferior and superior parietal cortices. The opposite contrast (mental rotation of 3-D cubes vs. 2-D matrices) yielded only frontal cortex activation. The findings also yield evidence for converging, overlapping activation patterns for 2-D and 3-D stimuli if working memory demands are increased. Results are discussed within the framework of current working memory models.

Adult↗
PubMed2005

Probabilistic 3D MRI atlas of the human cerebellar dentate/interposed nuclei.

In a previous study, a three-dimensional (3D) MRI atlas of the human cerebellar nuclei was introduced based on findings in one healthy human subject [Dimitrova, A., Weber, J., Redies, C., Kindsvater, K., Maschke, M., Kolb, F.P., Forsting, M., Diener, H.C., Timmann, D., 2002. MRI atlas of the human cerebellar nuclei. NeuroImage 17, 240-255]. The present MRI investigation was designed to study variability of the anatomy of the dentate/interposed nuclei in a larger group of healthy subjects. Similar to our previous study, iron-induced susceptibility artifacts were used to visualize the cerebellar nuclei as hypointensities on MR images. Data of 63 healthy subjects (27 female, 36 male; mean age 45.3+/-13.4 years, age range 22--71 years) were included. A 3D axial volume of the cerebellum was acquired using a T2*-weighted FLASH sequence on a Siemens Sonata 1.5 T MR scanner. Each volume was registered, re-sampled to 1.00 x 1.00 x 1.00 mm(3) voxel size and spatially normalized into a standard proportional stereotaxic space using SPM99. Dentate/interposed nuclei were traced on axial images and saved as regions of interest using MRIcro-software by two independent examiners. A probabilistic 3D MRI atlas of the cerebellar dentate/interposed nuclei is presented based on findings in all subjects.

Adolescent↗
PubMed2005

[Value of imaging for lymph node metastases from renal cell, bladder, prostate, penile, and testicular cancers].

Computed tomography (CT) imaging is the standard method for the assessment of lymph node metastases in renal cell and testicular cancer. In bladder cancer and prostate cancer the results of CT are not convincing due to a large number of false-negative findings and the prognostic relevance of undetected metastases. For both entities recent studies revealed that MR lymphography using iron oxide particles allows the detection of small metastatic lymph nodes. For penile cancer reliable results for imaging of lymph node metastases do not exist. PET imaging using [(18)F]-fluorodeoxyglucose (FDG) is the modality of choice in therapy control of seminomas but has no defined value in other urological malignancies. PET with [(11)C] choline and [(11)C] acetate offers great potential in staging and restaging of prostate cancer. Further investigations are necessary to determine the role of these new methods.

Humans↗
PubMed2005

Endovascularly or surgically treated vertebral artery and posterior inferior cerebellar artery aneurysms: clinical analysis and results.

OBJECTIVE: To describe the clinical results in patients with aneurysms of the vertebral artery and posterior inferior cerebellar artery complex (VA-PICA) treated by endovascular embolization or surgically in cases considered untreatable by endovascular methods. PATIENTS AND METHODS: During a 5-year-period a total of 28 patients with a VA-PICA complex aneurysm out of 600 patients received definitive treatment, 19 patients by endovascular embolization and 9 patients surgically. Mean age was 54 years (range 9-75 years). Clinical data, intraoperative observations and procedural complications were evaluated. The mean follow-up was 9 months. RESULTS: Hunt-Hess (HH) grades were HH 0-II in 10 patients (35.7 %), HH III in 6 patients (21.4 %) and HH IV + V in 12 patients (42.9 %). Aneurysm size ranged from 2 to 40 mm (mean size 5.5 mm). Aneurysm configuration was saccular 18, fusiform 7 and multilobed 3. Complete occlusion was achieved in all cases. Overall 67.9 % (n = 19) showed a favorable outcome (Glasgow Outcome Score IV + V). Overall procedure-related rate for permanent morbidity and mortality was 3.6 % (n = 1) and 3.6 % (n = 1), respectively. Predictive factors of clinical outcome were the initial clinical HH grade and the Fisher grade. CONCLUSION: Endovascular embolization is an effective method for the treatment of VA-PICA aneurysms. Surgical clipping is still an alternative and should be considered for "uncoilable" lesions. Outcomes showed a close correlation to the initial clinical state and were not dependent on the treatment modality.

Adolescent↗
PubMed2005

[Magnetic resonance imaging (MRI) of the pelvis in diagnosing endometriosis].

Widely accepted as an established method in the diagnostic imaging of diseases of the female pelvis, magnetic resonance imaging (MRI) holds promising potential for the diagnosis of endometriosis. This review describes the general prerequisites for performing MRI scans of the pelvis and presents, based on recent studies, an imaging protocol suited to the diagnosis of endometriosis. Typical manifestations and sites of endometriosis are discussed and illustrated with sample images. For endometriotic cysts and implants, axial T (1)-weighted, fat-saturated turbo spin echo sequences (TSE) have the highest diagnostic value. In diagnosing adenomyosis, sagittal T (2)-weighted TSE sequences visualise changes in the uterine zonal anatomy. In essence, MRI is capable of detecting many manifestations of endometriosis in a non-invasive, yet reliable manner, and its value in relation to laparoscopy must be considered as complementary.

Endometriosis↗