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PubMed2002

Functional magnetic particles for medical application.

Magnetic particles for medical applications have been developed by many researchers. Since magnetic particles have unique magnetic features not present in other materials, they can be applied to special medical techniques. Separation, immunoassay, magnetic resonance imaging (MRI), drug delivery, and hyperthermia are enhanced by the use of magnetic particles. Magnetite cationic liposomes (MCLs), one of the group of cationic magnetic particles, can be used as carriers to introduce DNA into cells since their positively charged surface associates with the negatively charged DNA. They can also be used as heat mediators for cancer therapy. Magnetic particles conjugated with tumor-specific antibodies have enabled tumor-specific contrast enhancement in MRI. In addition, antibody-conjugated magnetic particles were shown to target renal cell carcinoma cells, and are applicable to the hyperthermic treatment of carcinomas. The use of magnetic particles with their unique features will further improve medical techniques.

Journal Article↗

PubMedDate not supplied

A validity analysis of residential magnetic fields estimated from high-voltage transmission lines.

Between November 1994 and May 1995, indoor power frequency magnetic fields of 407 residences in northern Taiwan were assessed by short-term on site measurements and by modeling computerized power lines information from high-voltage transmission lines. The study residences were selected according to the distance from the transmission lines with cutoff points of 50 meters (m), 100 m, and 150 m, which gave rise to four categories of residences. The analysis showed that the measured magnetic fields were higher than the calculated magnetic fields for most residences, especially for those with lower measured magnetic fields. The measured and calculated magnetic fields showed an agreement of 0.93 (intra-class correlation coefficient, [ICC] = 0.93) for the residences within 50 m of the transmission lines. The ICC declined with the distance from the transmission lines with a lowest ICC of 0.42 for the residences located more than 149 m away from power lines. When both measured and calculated magnetic fields were categorized into three levels with cutoff points of 1 milligauss (mG) and 2 mG, the indices of agreement were very similar for the three residential categories within 149 m of the lines with Kappa (K) between 0.51 and 0.55. The K for the residences more than 149 m from the lines was low at 0.29. The ICC and K observed from a reduced sample of 114 residences presumably representative of all residences in northern Taiwan with respect to the distribution of household magnetic fields was 0.90 and 0.64, respectively. Our data show that using exclusively computerized power lines information to assess residential magnetic fields exposure entails a certain degree of exposure misclassification, but in the absence of direct measurement, this way of doing provides reasonable estimates of magnetic fields exposure within 100 m of transmission lines.

Air Pollution, Indoor↗

PubMed1999

Transcranial magnetic stimulation: applications in neuropsychiatry.

In the 1990s, it is difficult to open a newspaper or watch television and not find someone claiming that magnets promote healing. Rarely do these claims stem from double-blind, peer-reviewed studies, making it difficult to separate the wheat from the chaff. The current fads resemble those at the end of the last century, when many were falsely touting the benefits of direct electrical and weak magnetic stimulation. Yet in the midst of this popular interest in magnetic therapy, a new neuroscience field has developed that uses powerful magnetic fields to alter brain activity--transcranial magnetic stimulation. This review examines the basic principles underlying transcranial magnetic stimulation, and describes how it differs from electrical stimulation or other uses of magnets. Initial studies in this field are critically summarized, particularly as they pertain to the pathophysiology and treatment of neuropsychiatric disorders. Transcranial magnetic stimulation is a promising new research and, perhaps, therapeutic tool, but more work remains before it can be fully integrated in psychiatry's diagnostic and therapeutic armamentarium.

Animals↗

PubMed2001

Compact clinical MRI magnet design using a multi-layer current density approach.

In this work, a new method of optimization is successfully applied to the theoretical design of compact, actively shielded, clinical MRI magnets. The problem is formulated as a two-step process in which the desired current densities on multiple, co-axial surface layers are first calculated by solving Fredholm equations of the first kind. Non-linear optimization methods with inequality constraints are then invoked to fit practical magnet coils to the desired current densities. The current density approach allows rapid prototyping of unusual magnet designs. The emphasis of this work is on the optimal design of short, actively-shielded MRI magnets for whole-body imaging. Details of the hybrid numerical model are presented, and the model is used to investigate compact, symmetric, and asymmetric MRI magnets. Magnet designs are presented for actively-shielded, symmetric magnets of coil length 1.0 m, which is considerably shorter than currently available designs of comparable dsv size. Novel, actively-shielded, asymmetric magnet designs are also presented in which the beginning of a 50-cm dsv is positioned just 11 cm from the end of the coil structure, allowing much improved access to the patient and reduced patient claustrophobia. Magn Reson Med 45:331-340, 2001.

Magnetic Resonance Imaging↗

PubMed1990

NMR imaging in the earth's magnetic field.

The most important and very expensive part of a magnetic resonance imaging set-up is the magnet, which is capable of generating a constant and highly homogeneous magnetic field. Here a new MR imaging technique without the magnet is introduced. This technique uses the earth's magnetic field instead of a magnetic field created by a magnet. This new method has not yet reached the stage of medical application, but the first images obtained by MRIE (magnetic resonance imaging in the earth's field) show that the resolution is close to that expected based on sensitivity estimations.

Humans↗

PubMed1993

Analysis of water-macromolecule proton magnetization transfer in articular cartilage.

These studies were designed to establish which structural elements of cartilage are responsible for proton magnetization transfer between water (Hf) and macromolecules (Hr) observed in MRI studies on articular cartilage. Saturation transfer techniques were used to monitor magnetization transfer in vitro on samples of the two major constituents of cartilage: collagen and proteoglycan. Articular cartilage samples were also evaluated in vitro before and after the removal of the proteoglycan fraction. Isolated hydrated collagen exhibited a significant proton magnetization transfer rate with water. In contrast, proteoglycans exhibited no proton magnetization transfer. Articular cartilage, in vitro, exhibited a high degree of magnetization transfer with water protons consistent with previous MRI studies in vivo. Enzymatic removal of proteoglycan from the cartilage did not alter the magnetization transfer rate between Hr and Hf. These data demonstrate that the structure and concentration of the collagen matrix are the predominant determinants of the magnetization transfer process in articular cartilage with little or no contribution from proteoglycans. This specificity of the magnetization transfer effect may prove useful in the noninvasive evaluation of cartilage composition and structure in vivo.

Animals↗

PubMed2006

Magnetic resonance imaging is the diagnostic tool of choice in the preoperative evaluation of patients with partial anomalous pulmonary venous return.

BACKGROUND: Diagnosis of partial anomalous pulmonary venous return is usually suspected by echocardiography and often confirmed by cardiac catheterization. Magnetic resonance imaging is a powerful non-invasive diagnostic tool that can give accurate insight on systemic and pulmonary veins, cardiac anatomy and physiopathology. AIM: To test the diagnostic accuracy of magnetic resonance in patient with suspected partial anomalous pulmonary venous return. CASE PRESENTATION: Twenty consecutive patients (10 male, mean age: 27+/-20 years) with suspected partial anomalous pulmonary venous return underwent a magnetic resonance study comprehensive of Gadolinium-enhanced three-dimensional magnetic resonance angiography and phase-velocity-contrast in order to evaluate pulmonary and systemic venous anatomy and QP/QS. In 14 of them a cardiac catheterization was also performed. Anatomy findings and QP/QS result of both exams were compared. Sixteen patients underwent surgical correction. In the other four patients with QP/QS<1.5, surgical correction was not indicated according to the literature (1). Among patients who had both magnetic resonance and cardiac catheterization (14 patients) anatomical findings were concordant in 12 of them. In all operated patients, surgical findings were concordant with MRI report. There was a good correlation between magnetic resonance and cardiac catheterization QP/QS evaluation (mean value 2.23 and 2.4, respectively). CONCLUSION: In patients with suspected anomalous pulmonary venous return, magnetic resonance provides a comprehensive evaluation of pulmonary venous return and the amount of shunt, overcoming most of the limitations of echocardiography. Therefore magnetic resonance is a powerful diagnostic tool for indicating therapeutic management and surgical strategies for this group of patients, and can be considered a non-invasive alternative to cardiac catheterization.

Adolescent↗

PubMed2006

Intracranial thermotherapy using magnetic nanoparticles combined with external beam radiotherapy: results of a feasibility study on patients with glioblastoma multiforme.

We aimed to evaluate the feasibility and tolerability of the newly developed thermotherapy using magnetic nanoparticles on recurrent glioblastoma multiforme. Fourteen patients received 3-dimensional image guided intratumoral injection of aminosilane coated iron oxide nanoparticles. The patients were then exposed to an alternating magnetic field to induce particle heating. The amount of fluid and the spatial distribution of the depots were planned in advance by means of a specially developed treatment planning software following magnetic resonance imaging (MRI). The actually achieved magnetic fluid distribution was measured by computed tomography (CT), which after matching to pre-operative MRI data enables the calculation of the expected heat distribution within the tumor in dependence of the magnetic field strength. Patients received 4-10 (median: 6) thermotherapy treatments following instillation of 0.1-0.7 ml (median: 0.2) of magnetic fluid per ml tumor volume and single fractions (2 Gy) of a radiotherapy series of 16-70 Gy (median: 30). Thermotherapy using magnetic nanoparticles was tolerated well by all patients with minor or no side effects. Median maximum intratumoral temperatures of 44.6 degrees C (42.4-49.5 degrees C) were measured and signs of local tumor control were observed. In conclusion, deep cranial thermotherapy using magnetic nanoparticles can be safely applied on glioblastoma multiforme patients.

Adult↗

PubMed2026

Circular upcycling of waste toner into eco-safe superparamagnetic nano-Fe3O4@C core-shell pigment for sustainable magnetic leather coatings.

The widespread use of laser printing and photocopying technologies has led to the accumulation of waste toner powder (WTP), a chemically stable and potentially carcinogenic pollutant. Herein, a scalable pyrolysis approach is demonstrated for converting WTP into a functional magnetic pigment for magnetic leather finishing. Pyrolysis at 600 °C for 2 h, guided by thermogravimetric analysis, enabled controlled phase transformation monitored by hyphenated TGA-FTIR. The resulting material (WTP-600) was comprehensively characterised using VSM, FTIR, XPS, pXRD, FESEM, HRTEM, EDX, 57Fe Mössbauer analysis, ICP-OES and TOC analysis. These analyses confirm near-complete removal of the polymeric fraction during pyrolysis, leading to an ≈ 97% reduction in volume of pristine WTP and the formation of a carbonaceous shell coated on a superparamagnetic nanocrystalline Fe3O4 core (Fe3O4@C). The carbonaceous surface of WTP-600 is enriched with hydroxyl functionalities; it is eco-friendly, and its magnetic strength is ≈ 2.3-fold higher than that of pristine WTP. Both WTP and WTP-600 were formulated with a commercial leather-finishing dispersion and applied as surface finishing on leather. As anticipated, the magnetic strength of WTP-600-coated leather was approximately 2.3 times higher than that of WTP-RT-coated leather. Evaluation of coating performance parameters and organoleptic assessment demonstrated that WTP-600-coated leather exhibited superior surface finishing and tactile properties compared to WTP-RT-coated leather. Magnetic leather of various colours was successfully synthesised by incorporating different pigments into WTP-600, resulting in only a marginal reduction in magnetic properties. The magnetic pigment-coated leather was found to be microbiologically stable, environmentally safe, and cytocompatible with human epidermal HaCaT keratinocyte cell lines. The prepared magnetic leathers demonstrate significant potential for advanced applications, including adhesive-free wall tiling, educational tool fabrication, and energy harvesting from human motion.

Magnetic leather finishes↗

PubMed2006

A unilateral NMR magnet for sub-structure analysis in the built environment: the Surface GARField.

A new, portable NMR magnet with a tailored magnetic field profile and a complementary radio frequency sensor have been designed and constructed for the purpose of probing in situ the sub-surface porosity of cement based materials in the built environment. The magnet is a one sided device akin to a large NMR-MOUSE with the additional design specification of planes of constant field strength /B0/ parallel to the surface. There is a strong gradient G in the field strength perpendicular to these planes. As with earlier GARField magnets, the ratio G//:B0/ is a system constant although the method of achieving this condition is substantially different. The new magnet as constructed is able to detect signals 50mm (1H NMR at 3.2 MHz) away from the surface of the magnet and can profile the surface layers of large samples to a depth of 35-40 mm by moving the magnet, and hence the resonant plane of the polarising field, relative to the sample surface. The matching radio frequency excitation/detector coil has been designed to complement the static magnetic field such that the polarising B0 and sensing B1 fields are, in principal, everywhere orthogonal. Preliminary spatially resolved measurements are presented of cement based materials, including two-dimensional T1-T2 relaxation correlation spectra.

Construction Materials↗

PubMed2006

In vivo MR imaging of magnetically labeled human embryonic stem cells.

INTRODUCTION: Human embryonic stem cells (hES) have emerged as a potentially new therapeutic approach for treatment of heart and other diseases applying the concept of regenerative medicine. A method for in vivo visualization and tracking of transplanted hES would increase our understanding of in vivo hES behavior in both experimental and clinical settings. The aim of this study was to evaluate the feasibility of magnetic labeling and visualization of hES with magnetic resonance imaging (MRI). METHODS: hES were established and expanded according to standard procedures. After expansion, the cells were cultured under feeder free conditions and magnetically labeled by addition of dextran-coated Ferrum-oxide particles (Endorem) to the medium. Accumulation of small particles of iron-oxide (SPIO) in hES was assessed by Prussian blue staining and electron microscopy. For in vitro MRI, the labeled and unlabeled hES were examined in cell solution and after transplantation into explanted mouse heart ( approximately 100,000 cells) on a Bruker Avance DMX 500 vertical magnet at 11.75 T. A multi-slice, multi spin-echo T(2)-weighted images were obtained. For in vivo imaging, the experiments were performed on male Sprague-Dawley using Bruker Biospec 2.35 T magnet. The hES were directly injected ( approximately 500,000 cells) after surgical procedure (thoracotomy) into anterior left ventricular (LV) wall. Multi-slice T(2)-weighted gradient echo images were obtained using cardiac gating. RESULTS: hES appeared to be unaffected by magnetic labeling and maintained their ability to proliferate and differentiate. No additive agent for membrane permeabilisation was needed for facilitation of intracellular SPIO accumulation. Prussian blue and electron microscopy have revealed numerous iron particles in the cytoplasm of hES. On T(2)-weighted images, the labeled cells have shown well-defined hyopintense areas at the site of injection in anterior LV wall both in vitro and in vivo. CONCLUSIONS: It is feasible to magnetically label and visualize hES both in vitro and in vivo. MR visualization of magnetically labeled hES may be a valuable tool for in vivo tracking of hES.

Animals↗

PubMed2003

Static magnetic field therapy for symptomatic diabetic neuropathy: a randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To determine if constant wearing of multipolar, static magnetic (450G) shoe insoles can reduce neuropathic pain and quality of life (QOL) scores in symptomatic diabetic peripheral neuropathy (DPN). DESIGN: Randomized, placebo-control, parallel study. SETTING: Forty-eight centers in 27 states. PARTICIPANTS: Three hundred seventy-five subjects with DPN stage II or III were randomly assigned to wear constantly magnetized insoles for 4 months; the placebo group wore similar, unmagnetized device. INTERVENTION: Nerve conduction and/or quantified sensory testing were performed serially. MAIN OUTCOME MEASURES: Daily visual analog scale scores for numbness or tingling and burning and QOL issues were tabulated over 4 months. Secondary measures included nerve conduction changes, role of placebo, and safety issues. Analysis of variance (ANOVA), analysis of covariance (ANCOVA), and chi-square analysis were performed. RESULTS: There were statistically significant reductions during the third and fourth months in burning (mean change for magnet treatment, -12%; for sham, -3%; P<.05, ANCOVA), numbness and tingling (magnet, -10%; sham, +1%; P<.05, ANCOVA), and exercise-induced foot pain (magnet, -12%; sham, -4%; P<.05, ANCOVA). For a subset of patients with baseline severe pain, statistically significant reductions occurred from baseline through the fourth month in numbness and tingling (magnet, -32%; sham, -14%; P<.01, ANOVA) and foot pain (magnet, -41%; sham, -21%; P<.01, ANOVA). CONCLUSIONS: Static magnetic fields can penetrate up to 20mm and appear to target the ectopic firing nociceptors in the epidermis and dermis. Analgesic benefits were achieved over time.

Adult↗

PubMed1998

Force-detected magnetic resonance without field gradients.

A novel method of nuclear magnetic resonance (NMR) is described which promises to be preferable to known general methods at sample length scales below approximately 100 microm. Its advantages stem from the seemingly paradoxical combination of a homogeneous static magnetic field and detection of a mechanical force between a spin-bearing sample and a magnet assembly. In contrast to other methods of force-detected nuclear magnetic resonance (FDNMR), the method is characterized by better observation of magnetization, enhanced resolution, and no gradient (BOOMERANG), and it is generally applicable with respect to sample composition, pulse sequence, and magnetic field strength. Further advantages of portability and low cost stem from the small instrument volume and mass and promise to extend the use of NMR to new applications and environments. A sensitivity analysis, relevant to spectroscopy or imaging, quantifies the advantage of BOOMERANG relative to magnetic induction using microcoils and to FDNMR methods that rely on large gradients of the magnetic field at the sample.

Magnetic Resonance Spectroscopy↗

PubMed2003

Single point measurements of magnetic field gradient waveform.

Pulsed magnetic field gradients are fundamental to spatial encoding and diffusion weighting in magnetic resonance. The ideal pulsed magnetic field gradient should have negligible rise and fall times, however, there are physical limits to how fast the magnetic field gradient may change with time. Finite gradient switching times, and transient, secondary, induced magnetic field gradients (eddy currents) alter the ideal gradient waveform and may introduce a variety of undesirable image artifacts. We have developed a new method to measure the complete magnetic field gradient waveform. The measurement employs a heavily doped test sample with short MR relaxation times (T(1), T(2), and T(2)(*)<100 micros) and a series of closely spaced broadband radiofrequency excitations, combined with single point data acquisition. This technique, a measure of evolving signal phase, directly determines the magnetic field gradient waveform experienced by the test sample. The measurement is sensitive to low level transient magnetic fields produced by eddy currents and other short and long time constant non-ideal gradient waveform behaviors. Data analysis is particularly facile permitting a very ready experimental check of gradient performance.

Agar↗

PubMed2005

[Orthodontic brackets in high field MR imaging: experimental evaluation of magnetic field interactions at 3.0 Tesla].

PURPOSE: To evaluate static magnetic field interactions for 32 commonly used orthodontic brackets in a 3.0 T magnetic resonance imaging (MRI) system. MATERIALS AND METHODS: 32 orthodontic brackets consisting of a steel alloy (n = 27), a cobalt-chromium alloy (n = 2), ceramic (n = 1), ceramic with a steel slot (n = 1), and titanium (n = 1) from 13 different manufacturers were tested for magnetic field interactions in a static magnetic field at 3.0 T (Gyroscan Intera 3.0 T, Philips Medical Systems, Best, Netherlands). The magnetic deflection force F (z) [mN] was evaluated by determining the deflection angle beta [ degrees ] using the established deflection angle test according to the ASTM guidelines. The magnetic-field-induced rotational force F (rot) or torque was qualitatively determined using a 5-point grading scale (0: no torque; + 4: very strong torque). RESULTS: In 18 of the 32 brackets, the deflection angle beta was found to be > 45 degrees and the translational force exceeded the gravitational force F (G) on the particular bracket (F (z): 1.2 - 45.7 mN). The translational force F (z) was found to be up to 68.5 times greater than the gravitational force F (G) (F (z)/F (G): 1.4 - 68.5). The rotational force F (rot) was correspondingly high (+ 3/+ 4) for those brackets. For the remaining 14 objects, the deflection angles were < 45 degrees and the torque measurements ranged from 0 to + 2. The static magnetic field did not affect the titanium bracket and the ceramic bracket. No measurable translational and rotational forces were found. CONCLUSION: Of the 32 brackets investigated for magnetic field interactions at 3.0 T, 18 (56.25 %) were unsafe in the MR environment according to the ASTM guidelines. However, the forces measured were minimal compared to the forces generally necessary for dislodging these bonded orthodontic brackets from tooth surfaces. The implications of these results for orthodontic patients undergoing MR examinations at 3 Tesla are discussed.

Humans↗

PubMedDate not supplied

Human exposure to 4.0-Tesla magnetic fields in a whole-body scanner.

Details are given for the design, construction, properties, and performance of a large, highly homogeneous magnet designed to permit whole-body magnetic resonance imaging and spectroscopy at 4 T. The magnet has an inductance of 1289 H and a stored energy of 33.4 MJ at rated field. The health of a group of 11 volunteers who had varying degrees of exposure to this field was followed over a 12-month period and no change that could be associated with this exposure was detected. A mild level of sensory experiences, apparently associated with motion within the field of the magnet, was reported by some of the volunteers during some of their exposures. A questionnaire regarding sensory effects associated with magnetic resonance scanners and possibly caused by the static magnetic field of these instruments, was given to nine respondents who had experience within both 1.5-T scanners and this 4-T scanner and to another group of 24 respondents who had experience only within 1.5-T scanners. For the sensations of vertigo, nausea, and metallic taste there was statistically significant (p less than 0.05) evidence for a field-dependent effect that was greater at 4 T. In addition, there was evidence for motion-induced magnetophosphenes caused by motion of the eyes within the static field. These results indicate the practicality of experimental whole-body body scanners operating at 4 T and the possibility of mild sensory effects in humans associated with motion within a static magnetic field. The results also indicate the likelihood of a wide margin of safety for the exposure of noncompromised patients to the static fields of conventional magnetic resonance scanners operated at 1.5 to 2 T and below.

Adult↗

PubMed2000

Locoregional cancer treatment with magnetic drug targeting.

The specific delivery of chemotherapeutic agents to their desired targets with a minimum of systemic side effects is an important, ongoing challenge of chemotherapy. One approach, developed in the past to address this problem, is the i.v. injection of magnetic particles [ferrofluids (FFs)] bound to anticancer agents that are then concentrated in the desired area (e.g., the tumor) by an external magnetic field. In the present study, we treated squamous cell carcinoma in rabbits with FFs bound to mitoxantrone (FF-MTX) that was concentrated with a magnetic field. Experimental VX-2 squamous cell carcinoma was implanted in the median portion of the hind limb of New Zealand White rabbits (n = 26). When the tumor had reached a volume of approximately 3500 mm3, FF-MTX was injected intraarterially (i.a.; femoral artery) or i.v. (ear vein), whereas an external magnetic field was focused on the tumor. FF-MTX i.a. application with the external magnetic field resulted in a significant (P < 0.05), complete, and permanent remission of the squamous cell carcinoma compared with the control group (no treatment) and the i.v. FF-MTX group, with no signs of toxicity. The intratumoral accumulation of FFs was visualized both histologically and by magnetic resonance imaging. Thus, our data show that i.a. application of FF-MTX is successful in treating experimental squamous cell carcinoma. This "magnetic drug targeting" offers a unique opportunity to treat malignant tumors locoregionally without systemic toxicity. Furthermore, it may be possible to use these magnetic particles as a "carrier system" for a variety of anticancer agents, e.g., radionuclides, cancer-specific antibodies, and genes.

Animals↗

PubMedDate not supplied

Free breathing magnetic resonance cholangiopancreatography (MRCP) at end expiration: a new technique to expand clinical application.

BACKGROUND/AIMS: To develop a new magnetic resonance cholangiopancreatography technique for patients who cannot hold their breath or breathe regularly and fail to be successfully examined with conventional magnetic resonance cholangiopancreatography methods. METHODOLOGY: Within a one-year period, 15 patients including 6 children and 9 adults were studied. Magnetic resonance cholangiopancreatography was performed in a 1.5 Tesla GE MR scanner with capability of single-shot fast spin echo sequence. In all patients except for the children, magnetic resonance cholangiopancreatography was attempted with the breathhold technique at first. However, this failed in some due either to the patients being too old or too weak to hold their breath long enough for single-shot fast spin echo sequence, which usually took about 20-30 seconds for the complete scanning. These 15 cases were then scanned slice-by-slice in operator's control mode by monitoring patient's respiratory pattern from the TV monitor. Scanning was started near the end of patient's expiration. This technique was performed after we had carefully decided the baseline of each patient's respiration cycle. Each slice was scanned at an interval depending on the patient's respiratory frequency. It was acquired at an interval of two respiratory cycles for each sequential slice when the patient's respiration frequency was around 10-15 cycles per minute, at three cycles when respiration frequency was around 15-20, at four cycles when the frequency was around 20-25, and at an interval of 5 cycles when it was above 25. The acquired source images were then reconstructed for a 3D image. RESULTS: Magnetic resonance cholangiopancreatography of good image quality was obtained in all of these fifteen patients. Each set of images took about 2-3 minutes. No marked artifact was found. The reconstructed 3D image also afforded satisfactory quality for evaluation of both normal ductal anatomy and lesions of the biliary-pancreatic system. The axial single-shot fast spin echo sequence images of the liver and pancreas were also successfully obtained with this method. Magnetic resonance cholangiopancreatography findings in these 15 patients included type I choledochal cyst (n = 4), dilatation of the intrahepatic bile ducts due to mass compression (n = 3, one Klatskin tumor and two hilar masses), pancreatic carcinoma (n = 1), acute cholecystitis without biliary tract dilatation (n = 1), acute pancreatitis with mild biliary dilatation and non-visible pancreatic duct (n = 1), dilatation of biliary tract without definite lesions (n = 2), common hepatic duct obstruction (n = 1), and normal biliary and pancreatic duct without dilatation or lesions (n = 2). CONCLUSIONS: Free breathing magnetic resonance cholangiopancreatography technique is very useful for patients in whom conventional methods cannot be successfully undertaken. It affords informative images that are comparable to other magnetic resonance methods.

Aged↗