Biomedical subjects

Werner A Kaiser

Publications and source records attributed to Werner A Kaiser.

At least 37 records · Page 2Linked to original sources

PubMed2004

Early diagnosis of cerebral involvement in Sturge-Weber syndrome using high-resolution BOLD MR venography.

Sturge-Weber syndrome (SWS) is a congenital disorder characterized by a vascular birthmark and neurological abnormalities. Typical imaging findings using MRI or CT are superficial cerebral calcification, atrophy and leptomeningeal enhancement. We present a neonate diagnosed with SWS because of a port-wine stain. In the absence of neurological symptoms the first MRI was performed when he was 4 months old, and follow-up MRI studies were performed after his first seizure at the age of 12 months. MRI was performed using standard sequences before and after administration of IV gadolinium. A high-resolution T2*-weighted, rf-spoiled 3D gradient-echo sequence with first-order flow compensation in all three directions was used for additional venographic imaging [blood-oxygen-level-dependent (BOLD) venography]. The initial conventional MRI sequences did not demonstrate any abnormality, but BOLD venography identified leptomeningeal internal veins. Follow-up MRI after the first onset of seizures demonstrated strong leptomeningeal enhancement, while BOLD venography revealed pathological medullary and subependymal veins as well as deep venous structures. At this time there were the first signs of atrophy and CT showed marginal calcifications. This report demonstrates that high-resolution BOLD MR venography allows early diagnosis of venous anomalies in SWS, making early therapeutic intervention possible.

Brain Diseases↗

PubMed2004

Application of an exogenous hyperoxic contrast agent in MR mammography: initial results.

There is interest in applying novel methods to dynamic MR mammography (MRM). One such possibility is to administer an exogenous hyperoxic contrast agent, such as carbogen (95-98% O2 and 2-5% CO2) or pure oxygen (100% O2). We report our first experiences with these agents in a patient with an invasive lobular carcinoma. Fourteen dynamic series were acquired with an rf-spoiled 2D multislice gradient echo sequence, including three measurements while breathing air, four measurements with 100% oxygen, three measurements with air and four measurements with carbogen. Afterwards, 0.1 mmol/kg bw of Gd-DTPA was administered to obtain dynamic T1-weighted double-echo 3D axial gradient echo images (TR/TE1/TE2/alpha=7.8 ms/2 ms/4.76 ms/15 degrees) every 90 s up to 4.5 min after injection. The lesion was well delineated on the contrast-enhanced images, contrary to magnitude images reconstructed from the raw data sets acquired during air/oxygen/carbogen breathing. A ROI-based median-filtered signal-time course revealed a tumor signal increase of roughly 15% between scans acquired during air and oxygen breathing. Though preliminary, these first results are encouraging concerning the exploration of these alternative contrast agents in MRM in greater detail.

Breast Neoplasms↗

PubMed2004

Pediatric brain MRI in neurofibromatosis type I.

Neurofibromatosis (NF) is the most common of the phakomatoses, with a prevalence of 1 in 3-4,000. Many organ systems can be affected. In addition to multiple peripheral neurofibromas, NF I predisposed to CNS tumors including optic glioma, astrocytoma and plexiform neurofibroma. The purpose of this pictorial review is to illustrate characteristic brain MR imaging lesions in children with NF I and to give some recommendations about diagnostic imaging procedures in children suffering from NF I. Typical findings in brain MRI are hyperintense lesion on T2-weighted images, so-called unknown bright objects, which may be useful as an additional imaging criterion for NF I. Contrast administration is necessary in MR studies to maximize tumor detection and characterization, to add confidence to the diagnosis of benign probable myelin vacuolization, and to document stability of neoplasm on follow-up examinations. We recommend to perform serial MR imaging in children every 12 months. The frequency of follow-up in children with known brain tumors will vary with the tumor grade, biological activity and treatment.

Adolescent↗

PubMed2004

Near-infrared fluorescence imaging of HER-2 protein over-expression in tumour cells.

The aim of this study was to evaluate in vitro and in vivo imaging of HER-2-over-expressing tumours using near-infrared optical imaging. A fluorochrome probe was designed by coupling Cy5.5 to anti-HER-2 antibodies. Cells over-expressing (SK-BR-3 cells) or normally expressing (PE/CA-PJ34 cells) the HER-2 protein were incubated with the probe. After removing unbound probe molecules, fluorescence intensities were determined (a.u.: arbitrary units). Cells were additionally investigated using FACS and laser scanning microscopy. The probe was also injected intravenously into tumours bearing SK-BR-3 ( n=3) or PE/CA-PJ34 ( n=3). Whole-body fluorescence images were generated and analysed. The incubation of SK-BR-3 cells with the probe led to higher fluorescence intensities [2,133 (+/-143) a.u.] compared to controls [975 (+/-95) a.u.]. The results from FACS and immunocytochemical analysis were in agreement with these findings. A distinct dependency between the fluorescence intensity and the cell number used in the incubations was detected. In vivo, the relative fluorescence intensities in SK-BR-3 tumours were higher than in PE/CA-PJ34 tumours at 16-24 h after probe application. HER-2-over-expressing tumours were depictable in their original size. Labelling of HER-2 with Cy5.5 is suitable for in vitro and in vivo detection of HER-2-over-expressing tumour cells.

Animals↗

PubMed2004

Changes in magnetic resonance mammography due to hormone replacement therapy.

BACKGROUND: The aim of the present article is to investigate effects of hormone replacement therapy (HRT) on contrast medium enhancement patterns in postmenopausal patients during magnetic resonance mammography (MRM). MATERIALS AND METHODS: Two hundred and fifteen patients receiving hormonal medication were divided into four groups: 150 patients with 1 MRM during HRT (group A), 13 patients with 2 MRMs under HRT (group B), 30 patients with 1 MRM during HRT and 1 MRM after HRT withdrawal (group C), and 22 women with 1 MRM after HRT withdrawal (group D). Dynamic MRM was performed at 1.5 Tesla. Signal intensity changes were characterized by five time curves: minimal enhancement (type I), weak continuous enhancement (type II), strong continuous enhancement (type III), and a steep initial slope followed by a plateau phenomenon (type IV) or a washout effect (type V). RESULTS: Of all 193 patients under HRT (group A + group B + group C), 60 patients (31.1%) showed curve type I, 88 patients (45.6%) showed type II and 45 patients (23.3%) showed type III. There were significant differences to 52 patients after HRT withdrawal (group C + group D) (P < 0.0001), with 42 patients (80.8%) for curve type I, 8 patients (15.4%) for type II, and 2 patients (3.8%) for type III. In both MRM sessions in group B, 69% of the patients showed identical curve types without significant differences (P = 0.375). In group C, 28 of 30 patients (93%) dropped to lower curve types with significant differences in curve types during and after HRT (P < 0.0001). CONCLUSION: The majority of patients receiving postmenopausal HRT showed bilateral symmetrical, continuous enhancement without evidence of a plateau phenomenon or a washout effect due to HRT in MRM. Hormonal effects could be proven and were reproducible and reversible.

Adipose Tissue↗

PubMed2004

Effect of routine MR imaging of the brain at 1.5 T on subsequent magnetoencephalography: results in nine volunteers.

PURPOSE: To investigate whether routine magnetic resonance (MR) imaging of the brain with a whole-body 1.5-T imager affects the results of subsequent magnetoencephalography (MEG). MATERIALS AND METHODS: Nine healthy volunteers (six women, mean age of 23 years, age range of 20-27 years; three men, mean age of 24 years, age range of 23-25 years) underwent one MEG session before and two MEG sessions after MR imaging of the brain. The first MEG session was completed about 20 minutes before brain MR imaging began, the second MEG session (MEG 2) was performed within 30 minutes after MR imaging, and the third MEG session was performed 2 hours after MEG 2. Each MEG session involved measurement of spontaneous brain activity and, in seven patients, of brain activity during stimulation of the median nerve. MR imaging included T1- and T2-weighted fast spin-echo and gradient-echo sequences applied with a 1.5-T clinical imager. Data were compared by using a repeated-measures analysis of variance (general linear model) both with and without Greenhouse-Geisser correction. RESULTS: MEG signals were detected and measured without difficulty in all volunteers. No statistically significant difference was seen between estimated noise at MEG before and after MR imaging (P =.588 with correction, P =.665 without correction). MEG records obtained in all volunteers enabled localization of evoked response to median nerve stimulation before and after MR imaging. No measurable differences were observed between relative power spectra of spontaneous brain activity before and after MR imaging (P >.290 with correction, P >or=.295 without correction). CONCLUSION: No measurable effect of 1.5-T brain MR imaging on subsequent MEG was detected.

Adult↗

PubMed2004

High-flow priapism in acute lymphatic leukaemia.

Priapism is defined as prolonged and persistent erection of the penis without sexual stimulation. It is associated with excessive hyperleukocytosis (e.g. in acute or chronic leukaemia); however, this complication is rarely seen in the pediatric population. We report a 12-year-old boy suffering from acute leukaemia presenting with, at first intermittent, but increasingly persistent erection. Doppler US revealed signs of high-flow priapism. MRI excluded intrapelvic tumour masses, and three-dimensional contrast-enhanced MR angiography could not demonstrate an arteriovenous fistula or thrombosis. Cavernosal blood-gas measurement was in agreement with high-flow priapism. On the basis of the imaging findings, invasive therapeutic management was avoided in our patient with a successful outcome.

Child↗

PubMed2004

In vivo imaging of experimental arthritis with near-infrared fluorescence.

OBJECTIVE: To visualize early experimental arthritis with near-infrared fluorescence (NIRF) imaging in a murine model of antigen-induced arthritis (AIA). METHODS: The target of NIRF was the F4/80 antigen present on the surface of macrophages infiltrating the inflamed synovial membrane. Imaging was performed using anti-F4/80 monoclonal antibodies (mAb) labeled with Cy5.5 fluorochrome. On day 7 of AIA, 6 mice received an intravenous (IV) injection of labeled mAb; control AIA mice (n = 6) received an IV injection of Cy5.5-labeled isotype control antibody. NIRF imaging was performed before injection (baseline) and until 72 hours thereafter. Histologic evaluation of arthritis severity and immunohistochemical assessment of F4/80 antigen density were also performed on day 7. RESULTS: NIRF imaging showed an accumulation of fluorochrome probes in the inflamed knee joints and, to a lesser extent, in the contralateral (nonarthritic) knee joints. The signal induced by mAb F4/80 was clearly higher than that generated by the isotype control. Accumulation of fluorochrome probes in the joints was confirmed histologically by confocal laser scanning microscopy. CONCLUSION: The use of fluorochromes allows imaging of arthritis in the near-infrared range. Accumulation in the contralateral, nonarthritic knee joints can be explained by the presence of sentinel macrophages in normal synovium or by a mild contralateral response due to systemic activation or neurogenic mechanisms.

Animals↗

PubMed2004

Autofluorescence spectroscopy in whole organs with a mobile detector system.

RATIONALE AND OBJECTIVES: Autofluorescence can be exploited to obtain spectroscopic information about tissues or organs in a noninvasive fashion. The knowledge of normal organ patterns is a prerequisite for subsequent characterization of pathological states, eg, inflammation or tumors. Therefore, the aim of this study was to investigate the autofluorescence properties of healthy organs in mice. MATERIALS AND METHODS: Organs from C57Bl/6 mice were removed in toto and stored in physiologic sodium chloride solution on ice (non-perfused specimens). Investigations were performed with a custom-made mobile fluorescence detector. Excitation-emission matrices (EEMs) were measured in selected organs (bladder, brain, kidney, liver, and spleen) (n = 5). Afterwards, single-emission spectra were obtained in selected organs (bladder, colon, brain, kidney, liver, and spleen) and peak fluorescence signal intensities were calculated (n = 9). RESULTS: EEMs showed that excitation at wavelengths from 300-310 nm (emission spectra in all samples of bladder and brain; probably caused by collagen/elastin) and from 350-360 nm (emission spectra in all samples with the exception of spleen; probably caused by NAD(P)H) seem to be best suited for autofluorescence measurements in organs. The single-emission spectra measurements were noticeably different in terms of occurrence (yes/no response) and intensity of fluorescence emission peaks in different organs. CONCLUSION: Combined autofluorescence measurements of collagen/elastin (for structural information) and NAD(P)H (for functional information) allow conclusions about the target organs. Therefore, autofluorescence measurements seem to be a diagnostic tool feasible for characterization of tissue.

Animals↗

PubMed2004

Event-related fMRI with painful electrical stimulation of the trigeminal nerve.

Several functional brain imaging studies of pain using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) have shown that painful stimulation causes activation of different brain areas. The aim of the present study was to develop and implement painful stimulation of the trigeminal nerve, which can be applied with event-related paradigms by using MRI. Twelve healthy, right-handed volunteers were examined. Painful electrical stimulation of the first trigeminal branch was performed. In an event-related setting with a 1.5 T clinical scanner with EPI capability, the following fMRI parameters were used: 20 slices, 3 mm thickness, isotropic voxel, 306 measurements with 54 randomized events. Statistical postprocessing was performed with SPM99. Activation of the ipsi- and contralateral secondary somatosensory cortex (SII), and the contralateral insular cortex was observed as well as a contralateral thalamic activation (T=4.45, extension 15 voxels). Six of the 12 volunteers revealed also activation of the cingulate cortex. The investigation demonstrates that painful stimulation of the trigeminal nerve activates the contralateral insular cortex, SII, and thalamus, as well as the ipsilateral SII. In contrast to other studies, the cingulate cortex was only activated inconsistently.

Adult↗

PubMed2004

Are unnecessary follow-up procedures induced by computer-aided diagnosis (CAD) in mammography? Comparison of mammographic diagnosis with and without use of CAD.

OBJECTIVE: To evaluate the rate of unnecessary follow-up procedures recommended by radiologists using a CAD-system. MATERIALS AND METHODS: 185 patients (740 images) were consecutively selected from three groups (36 histologically proven cancers = group 1; 49 histologically proven benign lesions = group 2 and 100 screening cases (4 years-follow up = group 3). Mammograms were evaluated by a CAD system (Second Look, CADx, Canada). Five blinded radiologists assessed the images without/with CAD outputs. Diagnostic decisions were ranked from surely benign to surely malignant according to BIRADS classification, follow-up procedures were recommended for each observed lesion (a, screening; b, short interval follow-up examination in 6 months; c, pathologic clarification). RESULTS: CAD-system detected 32/36 cancers (88.9%) (FP-rate: 1.04 massmarks and 0.27 calcmarks/image). The following values were reached by all observers without/with CAD in the mean: Sensitivity 80.6/80.0%, specificity 83.2/86.4%, PPV 53.1/58.1%, and NPV 94.6/94.7%. Observers described a similar number of additional lesions without/with the use of CAD (325/326). Whereas the number of unnecessary short-time follow up recommendations increased in all case-subgroups with CAD: 40.8/42.9% (group 1), 35.6/38.1% (group 2), 44.7/46.8% (group 3), respectively, the number of recommended biopsies decreased in all subgroups: group 1: 34.7/27.1%; group 2: 47.4/41.5%, group 3: 33.3/22.0%, respectively. CONCLUSION: In this rather small population additional usage of CAD led to a lower rate of unnecessary biopsies. The observed decrease of recommended unnecessary biopsies due to the usage of CAD in the screening group suggests a potential financial benefit by using CAD as diagnostic aid.

Breast Neoplasms↗

PubMed2004

Diagnosis of arthritis using near-infrared fluorochrome Cy5.5.

PURPOSE: Near-infrared range fluorescence (NIRF) imaging is a potential tool to diagnose biologic processes in vivo. This applicability study sought to define whether imaging with fluorochrome Cy5.5 can identify arthritis in murine antigen-induced arthritis (AIA). MATERIALS AND METHODS: On day 7 of AIA (n = 9 mice), fluorescence intensities in inflamed and contralateral knee joints (the latter as internal control) were measured before and after intravenous injection of Cy5.5 (until 72 hours). Cy5.5 joint deposition was verified by confocal laser-scanning microscopy. Dye phagocytosis was evaluated in cultured macrophages (cell line PMJ2-R) by FACS analysis. Cy5.5 binding to serum protein was tested by NIRF scanning and gel electrophoresis. RESULTS: Between 2 and 72 hours, the arthritic knee joints showed significantly higher fluorescence intensities compared with contralateral joints. Microscopy confirmed Cy5.5 deposition in the synovial membrane. Cultured macrophages actively phagocytosed Cy5.5. Cy5.5 bound mainly to albumin as the main serum protein. CONCLUSION: NIRF imaging with Cy5.5 can identify arthritic joints in vivo, likely due to nonspecific deposition.

Animals↗

PubMed2003

Influence of breast lesion size and histologic findings on tumor detection rate of a computer-aided detection system.

PURPOSE: To evaluate associations between histopathologic findings, tumor size, and detection rate of malignant mammographic findings by using a computer-aided detection (CAD) system. MATERIALS AND METHODS: The study included 208 mammographically detected histologically proven malignant breast lesions in 208 women. Findings were 150 masses and 114 microcalcifications; 56 lesions showed both findings; 94 lesions, mass only; and 58 lesions, microcalcification only. CAD was used to evaluate mammograms in two views retrospectively. Also, corresponding histopathologic findings and lesion size were evaluated. CAD marks were considered positive if, on at least one view, they correctly identified the corresponding mammographic lesion location. RESULTS: Ninety percent (135 of 150) of masses and 93.0% (106 of 114) of microcalcifications were marked correctly by the CAD system. Overall tumor detection rate was 93.8% (195 of 208). Size-related detection rate for masses was 83.3% (25 of 30) for lesions up to 10 mm, 100% (45 of 45) for lesions 11-20 mm, 100% (46 of 46) for lesions 21-30 mm, 83.3% (10 of 12) for lesions 31-40 mm, and 52.9% (nine of 17) for lesions larger than 40 mm. Size-related tumor detection rate for microcalcifications was 92.5% (37 of 40) for microcalcifications up to 10 mm, 93.1% (27 of 29) for lesions 11-20 mm, 100% (20 of 20) for lesions 21-30 mm, 87.5% (seven of eight) for lesions 31-40 mm, and 88.2% (15 of 17) for larger microcalcifications. Detection rates for mammographically visible masses (invasive ductal carcinoma, invasive lobular carcinoma, invasive tubular carcinoma, noninvasive cancers, mucinoid cancers, and others) were 92.3% (84 of 91), 89.3% (25 of 28), 75.0% (six of eight), 100% (15 of 15), 33.3% (one of three), and 80.0% (four of five), respectively. Detectability rates for mammographically visible areas suspicious for microcalcifications (invasive ductal carcinoma, invasive lobular carcinoma, invasive tubular carcinoma, and noninvasive cancers) were 92.3% (60 of 65), 100% (eight of eight), 100% (five of five), and 91.9% (31 of 34), respectively. Highest overall detection rates were observed for invasive ductal carcinomas (96.6% [112 of 116]) and noninvasive cancers (92.9% [39 of 42]). CONCLUSION: Highest detection rates were observed for 10-30-mm tumor masses and for invasive ductal carcinomas and noninvasive cancers.

Breast↗

PubMed2003

Electrical impedance scanning-application of this new technique for lymph node evaluation in children.

BACKGROUND: Precise assessment of lymph nodes is crucial to the choice of therapy and prediction of outcome in cases of malignancy. Electrical impedance scanning (EIS) is being experimentally investigated for potential use as a diagnostic tool for differentiation of malignant lesions. Malignancies show different electrical properties with changes in conductivity and capacitance that can be analysed by EIS. Using a TransScan TS-2000 (TransScan Medical, Migdal Ha'Emek, Israel, distributed by Siemens-Elema AB, Solna, Sweden), EIS has been used in various studies for the identification of breast cancer as well as for characterisation of superficial lesions. OBJECTIVE: To evaluate the reliability of EIS for classifying lymph nodes in a pediatric population with sonographically suspicious lesions and to prove its accuracy. MATERIALS AND METHODS: The study population consisted of 77 children (42 boys, 35 girls) aged 1.1-17.1 years. All EIS results were compared to either histopathological findings or long-term follow-up investigations. RESULTS: Sensitivity for malignancies using EIS was 75% and specificity was 87%. The negative predictive value was 93% and the positive predictive value was 60%. CONCLUSIONS: This study suggests the potential usefulness of EIS as an additional imaging modality for the differentiation of lymph-node diseases in children. The histopathological spectrum of malignant lymph node transformation in children compared to studies in adults, and the characteristic meltdown in inflammatory or granulomatous transformed nodes, pose challenges to differentiation based on sonographic evaluation, and also to EIS classification.

Adolescent↗

PubMed2003

A manipulator system for 14-gauge large core breast biopsies inside a high-field whole-body MR scanner.

PURPOSE: To investigate a robotic manipulator system for MR-guided breast biopsies inside a 1.5 T whole-body magnet. MATERIALS AND METHODS: Fourteen patients with suspicious breast lesions (diameter 18.6 +/- 12 mm) underwent biopsy. Patients with malignant findings underwent surgery afterwards and the histologic findings between biopsy and surgery were correlated. RESULTS: In five patients biopsy findings were histopathologically confirmed following open surgery. One tubular carcinoma was missed; one invasive cancer was underestimated. Seven patients with benign findings are still in the follow-up period. CONCLUSION: The study demonstrates the feasibility to perform breast biopsies inside the magnet of a whole-body MR scanner by using a manipulator system.

Biopsy↗

PubMed2003

Animal-based model to investigate the minimum tumor size detectable with an electrical impedance scanning technique.

RATIONALE AND OBJECTIVES: The purpose of this study was to determine the minimum tumor size detectable with electrical impedance scanning (EIS) in laboratory animals. MATERIALS AND METHODS: VX2 tumor cells (1 mm3) were implanted bilaterally into the upper leg musculature of five white New Zealand rabbits. EIS and ultrasound (US) were performed before, during, and immediately after implantation and on every 2nd day thereafter until tumors could be visualized with both modalities. This was followed by an extended follow-up regimen until a tumor size of 1 cm3 was reached. Rabbits were anesthetized subcutaneously. RESULTS: Tumors could not be implanted in one rabbit. Neither EIS nor US were performed in one rabbit due to severe skin alterations at the implantation site. No focal increase in conductance was visible before or immediately after tumor injection. The smallest tumor identified with EIS was determined with US to be approximately 8 mm3. The mean tumor size at initial detection was 52 mm3 (determined with EIS). In two cases, the tumor was first seen with US (EIS detection was delayed with a delay of 1 and 2 days, respectively). In all remaining cases, tumors were detected simultaneously with both EIS and US. All tumors were visible with EIS. CONCLUSION: The animal-based model is feasible. VX2 tumors are detectable with EIS. Tumors characterized by a focal spot at EIS could be detected starting at a tumor size of 7.5 mm3.

Animals↗

PubMed2003

[Interventional MR-mammography: manipulator-assisted large core biopsy and interstitial laser therapy of tumors of the female breast]].

The present study investigated the clinical application of magnetic resonance (MR)-guided breast interventions, such as manipulator-assisted large core breast biopsy (LCBB) inside a 1.5 T whole-body magnet and MR-guided interstitial laser therapy (ILT). Sixteen patients underwent LCBB and 1 additional patient underwent 4 sessions of ILT of a recurrent undifferentiated lymph node metastasis in the axilla using a Nd-YAG laser (1064 nm). Temperature changes of the tumor tissue during ILT were monitored using phase images of a gradient echo sequence (GRE) (TR/TE/FA = 25/12/30). In 5 patients the biopsy findings were histopathologically confirmed after open surgery. In 3 patients, the biopsy missed one tubular and one ductal carcinoma; one invasive carcinoma was underestimated. Eight patients with benign findings are still in the follow-up period. The heating zone during ILT was well delineated on subtracted phase images. No severe adverse events were observed with LCBB or ILT. MR-guided breast biopsies are feasible with the manipulator system inside a whole-body 1.5 Tesla MR scanner. GRE information is suitable for therapy monitoring during ILT within the tumor. Further studies are necessary to evaluate the accuracy of the manipulator system and the efficacy of ILT in the treatment of breast lesions.

Aged↗

PubMed2003

Dedicated double breast coil for magnetic resonance mammography imaging, biopsy, and preoperative localization.

RATIONALE AND OBJECTIVES: The aim of this study was to compare the performance of a dedicated double breast coil for MR imaging and intervention with a standard diagnostic double breast coil. MATERIALS AND METHODS: Signal-to-noise ratios (SNRs) were determined for both coils by using a water phantom. Fourteen patients were examined, 11 underwent preoperative hookwire localization, two were biopsied, and one received diagnostic imaging. Breast images were acquired in three patients with both coils and were visually compared. Harvested specimen from the biopsies and surgeries following hookwire localization were histopathologically evaluated. RESULTS: SNR was superior with the interventional coil in the posterior (axillary) part of the imaging volume and inferior in the anterior part compared with the standard coil. Anatomic MR breast images were of similar diagnostic quality. For the two biopsy procedures the trocar was correctly placed in front of the suspicious lesion. Hookwires were correctly located inside the lesion in nine patients and in contact with the lesion in one patient. In one patient a 2 mm distance between the lesion and the wire was observed. CONCLUSIONS: Diagnostic imaging followed by subsequent MR-guided intervention is possible within a single session by using the dedicated interventional coil. The correct final position of the hookwires demonstrates the precision of the MR guided localization procedure.

Adult↗