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PubMed2001

High-resolution turbo magnetic resonance angiography for diagnosis of Moyamoya disease.

BACKGROUND AND PURPOSE: High-resolution turbo MR angiography with zero-filling interpolation (ZFI) technique is a new vascular imaging method with reduced scan time. The purpose of the present study was to evaluate high-resolution turbo MR angiography for the diagnosis and assessment of moyamoya disease. METHODS: Forty-six patients suspected of having moyamoya disease were examined with high-resolution turbo MR angiography with the ZFI technique, MRI, and conventional angiography. Moyamoya disease was diagnosed in 42 of these patients. Blind, separate interpretation of the images was performed. RESULTS: High-resolution turbo MR angiography and MRI accurately evaluated 349 (95%) and 325 (88%) of 368 arteries, respectively, but the degree of stenosis was overestimated in the other arteries. MR angiography and MRI depicted basal cerebral moyamoya vessels in 82 (98%) and 82 (98%) of 84 hemispheres, respectively. MR angiography also depicted leptomeningeal and transdural collateral vessels in 51 (100%) of 51 hemispheres and in 38 (88%) of 43 hemispheres, respectively. The sensitivity and specificity of high-resolution turbo MR angiography for the diagnosis of moyamoya disease were 98% and 100%, respectively. CONCLUSIONS: High-resolution turbo MR angiography in reduced scan time is highly accurate in the assessment of both steno-occlusive lesions and collateral vessels in moyamoya disease, thus providing a highly accurate (98%) diagnosis and assessment of moyamoya disease.

Adolescent↗

PubMed2002

TIMI myocardial perfusion grade and ST segment resolution: association with infarct size as assessed by single photon emission computed tomography imaging.

BACKGROUND: The TIMI myocardial perfusion grade (TMPG) and ST-segment resolution both reflect perfusion and are associated with mortality after thrombolysis for acute myocardial infarction. We hypothesized that these measures would also be associated with infarct size by single photon emission computed tomography (SPECT). Methods and Results- In the LIMIT AMI trial (Limitation of Myocardial Injury following Thrombolysis in Acute Myocardial Infarction) of lytic monotherapy versus lytic plus rhuMAb CD18, early 90-minute TMPG (n=221) and ST segment resolution (n=242) were compared with subsequent SPECT Technetium-99 m Sestamibi, measuring the percentage of the left ventricle with no Sestamibi uptake. Infarct sizes were larger with TMPG 0 or 1 (a closed or stained myocardium) than with TMPG 2 or 3 (open myocardium, median 13% versus 7%, P=0.004). Infarcts were also larger in patients with no ST segment resolution (median 15%) or incomplete resolution (11%) than in those with complete resolution (6%, overall P=0.0001). The difference in infarct size by TMPG persisted when stratified by category of ST resolution. CONCLUSIONS: There may be a pathophysiological link between early restoration of tissue-level perfusion and reduced subsequent infarct size that may partially explain why these early angiographic and electrocardiographic measures are associated with long-term survival.

Coronary Angiography↗

PubMed1985

Deterioration of oxygenation and abnormal lung microvascular permeability during resolution of leukopenia in patients with diffuse lung injury.

To determine whether circulating leukocytes contribute to gas exchange abnormalities in diffuse lung injury, we retrospectively examined oxygenation in 6 patients who met 3 criteria: leukopenia caused by marrow aplasia from remission-inducing chemotherapy for myelogenous leukemia, the eventual resolution of leukopenia, and concurrent acute respiratory failure diagnosed clinically as increased permeability pulmonary edema. Four of the 6 patients abruptly developed overt clinical evidence of pulmonary dysfunction within the 96 h preceding the resolution of the peripheral leukopenia. In all 6 patients, the alveolar to arterial oxygen tension difference increased between leukocyte counts. The mean value for the alveolar to arterial oxygen tension difference for the group doubled during this period (148 +/- 37 mmHg 3 days prior to resolution; 290 +/- 37 mmHg 1 day after resolution; p less than 0.05). As an index of lung capillary permeability, we measured the lung permeability-surface area product for urea (PSu) for an additional patient with oxygen toxicity and drug-induced leukopenia whose hypoxemia increased immediately before the resolution of leukopenia. The PSu in this patient was high, in the range previously reported as being highly specific for increased permeability pulmonary edema with a fatal outcome. We conclude that such diffuse lung injury resembling the adult respiratory distress syndrome can occur in leukopenic patients, but the resolution of leukopenia in such patients may be associated with worsening oxygenation and with abnormally high pulmonary microvascular permeability. These observations do not prove a causal relationship but provide a clinical parallel to several leukocyte-depletion studies reported in animal models of increased permeability pulmonary edema that implicate white blood cells in the pathogenesis of hypoxemia and lung edema.

Adult↗

PubMed2003

Peripheral resolution for achromatic and SWS gratings in early to moderate glaucoma and the implications for selective ganglion cell density loss.

PURPOSE: To investigate whether there is significant selective reduction in short-wavelength-sensitive (SWS) ganglion cell density in early to moderate glaucoma. METHODS: Peripheral achromatic resolution acuity (an indirect measure of the underlying midget ganglion cell density) and peripheral chromatic resolution acuity under conditions of blue cone isolation (an indirect measure of the underlying small bistratified ganglion cell density) were measured at 13 degrees eccentricity in four oblique meridians in 15 eyes (mean age, 64.6 +/- 9.6 years) with early to moderate glaucoma. The results from the subjects with glaucoma were compared with those in a group of 17 age-matched normal eyes (mean age, 62.5 +/- 6.6 years). RESULTS: Mean achromatic resolution acuity across the four locations was significantly lower in the subjects with glaucoma than in the normal subjects (2.92 vs. 4.01 cyc/deg). Mean chromatic resolution acuity across the four locations was also significantly lower in the subjects with glaucoma than the normal subjects (0.78 vs. 0.99 cyc/deg). There was no selective loss of mean SWS acuity in the subjects with glaucoma. Individual location analysis revealed that the chromatic-achromatic resolution ratio was not significantly different in the subjects with glaucoma who had early glaucomatous damage when compared with the normal subjects. The chromatic-achromatic resolution ratio was lower than normal at certain locations in certain individuals with early glaucoma. CONCLUSIONS: The results indicate that there is no evidence of significant selective reduction in global SWS ganglion cell density in early to moderate glaucoma. However, there may be selective loss of SWS ganglion cell density at individual locations in individual eyes.

Aged↗

PubMed2006

Differences between recognition and resolution acuity in patients undergoing macular hole surgery.

PURPOSE: The present investigation compared recognition acuities (ETDRS chart) with resolution acuities (Landolt-C chart) in a sample of patients with idiopathic macular holes (MH). Traditionally, visual acuity in a clinical setting is measured with a letter chart. Yet, the ability to recognize a letter differs from a resolution task, such as detecting the direction of a gap in a ring. It was hypothesized that resolution acuity would be more impaired than recognition acuity in patients with MH, because component cues in letter optotypes are not available in Landolt-Cs. METHOD: Visual acuities of 23 patients with MH (age range, 52-82) were tested, using standard ETDRS and Landolt-C charts. Optical coherence tomography was used to confirm the diagnosis of MH. RESULTS: Acuities correlated strongly, before and after surgery (r = 0.92 and r = 0.95, respectively). However, paired t-tests determined that resolution acuity was significantly more impaired at both time points than was recognition acuity (P < 0.001). Using Bland-Altman plots, the limits of agreement between the two acuity types indicated that resolution acuity differed from recognition acuity by up to five lines before surgery and up to 3 lines after surgery. CONCLUSIONS: ETDRS and Landolt-C acuities differ in a clinically significant way in patients before and after MH surgery. Measuring recognition acuity by reading letters may lead to an overestimate of visual ability at the retinal level in patients with MH by including compensatory top-down cognitive processes that are unavailable for resolution tasks.

Aged↗

PubMed2006

Noninvasive volumetric imaging and morphometry of the rodent retina with high-speed, ultrahigh-resolution optical coherence tomography.

PURPOSE: To demonstrate high-speed, ultrahigh-resolution optical coherence tomography (OCT) for noninvasive, in vivo, three-dimensional imaging of the retina in rat and mouse models. METHODS: A high-speed, ultrahigh-resolution OCT system using spectral, or Fourier domain, detection has been developed for small animal retinal imaging. Imaging is performed with a contact lens and postobjective scanning. An axial image resolution of 2.8 mum is achieved with a spectrally broadband superluminescent diode light source with a bandwidth of approximately 150 nm at approximately 900-nm center wavelength. Imaging can be performed at 24,000 axial scans per second, which is approximately 100 times faster than previous ultrahigh-resolution OCT systems. High-definition and three-dimensional retinal imaging is performed in vivo in mouse and rat models. RESULTS: High-speed, ultrahigh-resolution OCT enabled high-definition, high transverse pixel density imaging of the murine retina and visualization of all major intraretinal layers. Raster scan protocols enabled three-dimensional volumetric imagingand comprehensive retinal segmentation algorithms allowed measurement of retinal layers. An OCT fundus image, akin to a fundus photograph was generated by axial summation of three-dimensional OCT data, thus enabling precise registration of OCT measurements to retinal fundus features. CONCLUSIONS: High-speed, ultrahigh-resolution OCT enables imaging of retinal architectural morphology in small animal models. OCT fundus images allow precise registration of OCT images and repeated measurements with respect to retinal fundus features. Three-dimensional OCT imaging enables visualization and quantification of retinal structure, which promises to allow repeated, noninvasive measurements to track disease progression, thereby reducing the need for killing the animal for histology. This capability can accelerate basic research studies in rats and mice and their translation into clinical patient care.

Animals↗

PubMed2004

Clinical implications of ST-segment non-resolution after thrombolysis for myocardial infarction.

Failed reperfusion after thrombolytic therapy for acute myocardial infarction is common and signifies a poor prognosis. We investigated the clinical consequences of non-resolution of the ST segment after thrombolytic therapy for acute ST-elevation myocardial infarction, in 85 consecutive patients admitted to a coronary care unit lacking rapid access to angioplasty. Failed thrombolysis was defined as <50% ST-segment resolution 180 minutes after the start of thrombolytic treatment. Outcomes were measured in terms of in-hospital adverse events, length of hospital stay, and mortality at 6 weeks and 1 year. Thrombolysis was successful, in terms of ST-segment resolution, in 45 patients (53%). After adjustment for other factors, ST resolution was the only independent predictor of an uncomplicated recovery in hospital (odds ratio 6.8, 95% confidence interval 2.3 to 19.9; P<0.001). At 6 weeks and 1 year, overall mortality was lower in the ST resolution group, though these differences became non-significant on multivariate analysis. In patients who survived to hospital discharge, median length of stay was greater in successfully thrombolysed patients (9 days versus 8 days) despite their lower rate of complications. ST-segment resolution is a useful marker of successful thrombolysis and relates to clinical outcome. If assessed routinely it might assist, along with other clinical markers, in the identification of low-risk patients who can be discharged early.

Aged↗

PubMed1987

MRI vs. high-resolution CT scanning: evaluation of the anterior skull base.

While magnetic resonance imaging (MRI) is no longer a tool of the future, its availability is limited. Most hospitals still use high-resolution computed tomography (CT) scanning as their major imaging modality. Although numerous articles point to the improved diagnostic uses of MRI--as compared to high-resolution CT--a change from high-resolution CT scanning to MRI scanning throughout the United States would cost billions of dollars. We should, therefore, delineate those clinical situations in which magnetic resonance imaging is distinctly superior to high-resolution CT scanning. It is already an accepted fact that MRI provides improved imaging of the central nervous system, but, while recent articles maintain the superiority of MRI head and neck imaging, the advantages to the clinician are less clear. We present representative cases of large malignant tumors of the frontal, ethmoid, and sphenoid sinuses, in which the full extent of the disease which involved intracranial structures and the orbit was better defined on the MRI scan than it was on the high-resolution CT scan. Decisions concerning the involvement of the infratemporal fossa, the cavernous sinus, the optic chiasm, the pituitary, and the frontal lobes were more easily made when based upon magnetic resonance imaging, while the tumor involvement as evaluated by CT scanning was much less clear. Establishment of the problem regions of the head and neck--when magnetic resonance imaging is superior to high-resolution CT scanning--will assist in identification of the true need for this tool in the practice of the otolaryngologist--head and neck surgeon.

Adenoma↗

PubMed2004

[High resolution reconstruction of PET images using the iterative OSEM algorithm].

AIM: Improvement of the spatial resolution in positron emission tomography (PET) by incorporation of the image-forming characteristics of the scanner into the process of iterative image reconstruction. METHODS: All measurements were performed at the whole-body PET system ECAT EXACT HR(+) in 3D mode. The acquired 3D sinograms were sorted into 2D sinograms by means of the Fourier rebinning (FORE) algorithm, which allows the usage of 2D algorithms for image reconstruction. The scanner characteristics were described by a spatially variant line-spread function (LSF), which was determined from activated copper-64 line sources. This information was used to model the physical degradation processes in PET measurements during the course of 2D image reconstruction with the iterative OSEM algorithm. To assess the performance of the high-resolution OSEM algorithm, phantom measurements performed at a cylinder phantom, the hotspot Jaszczack phantom, and the 3D Hoffmann brain phantom as well as different patient examinations were analyzed. RESULTS: Scanner characteristics could be described by a Gaussian-shaped LSF with a full-width at half-maximum increasing from 4.8 mm at the center to 5.5 mm at a radial distance of 10.5 cm. Incorporation of the LSF into the iteration formula resulted in a markedly improved resolution of 3.0 and 3.5 mm, respectively. The evaluation of phantom and patient studies showed that the high-resolution OSEM algorithm not only lead to a better contrast resolution in the reconstructed activity distributions but also to an improved accuracy in the quantification of activity concentrations in small structures without leading to an amplification of image noise or even the occurrence of image artifacts. CONCLUSION: The spatial and contrast resolution of PET scans can markedly be improved by the presented image restauration algorithm, which is of special interest for the examination of both patients with brain disorders and small animals.

Algorithms↗

PubMed2002

Estimation of longitudinal resolution in optical coherence imaging.

The spectral shape of a source is of prime importance in optical coherence imaging because it determines several aspects of image quality, especially longitudinal resolution. Wide spectral bandwidth, which provides short coherence length, is sought to obtain high-resolution imaging. To estimate longitudinal resolution, the spectral shape of a source is usually assumed to be Gaussian, although the spectra of real sources are typically non-Gaussian. We discuss the limit of this assumption regarding the estimation of longitudinal resolution. To this end, we also investigate how coherence length is related to longitudinal resolution through the evaluation of different definitions of the coherence length. To demonstrate our purpose, the coherence length for several theoretical and real spectral shapes of sources having the same spectral bandwidth and central wavelength is computed. The reliability of coherence length computations toward the estimation of longitudinal resolution is discussed.

Journal Article↗

PubMed2003

Resolution of synthetic-aperture imaging through turbulence.

A theory is developed for the resolution of an optical synthetic-aperture imaging system viewing an object through an inhomogeneous refractive medium. The inhomogeneities of the propagation medium create errors in the phase history data with resultant space-variant image effects, including geometric distortions and broadening of the impulse response or point-spread function. I relate the intensity-impulse response to the usual wave structure function. I determine the modulation transfer function for synthetic apertures of any size and exposure time, valid whenever the optical bandwidth is small compared with the carrier frequency, and derive the resolution for monostatic and bistatic synthetic apertures, valid whenever the real sampling aperture is small compared with the medium's coherence length. The results take the same form as the well-known turbulence-limited resolution of incoherent, real-aperture imaging with short exposure. Turbulence-limited synthetic-aperture resolution is somewhat better than incoherent real-aperture resolution under the same conditions. Autofocus processing improves synthetic-aperture resolution beyond this limit, and adaptive correction of higher-order phase history errors would improve it further.

Journal Article↗

PubMed2005

Depth resolution and displayable depth of a scene in three-dimensional images.

The depth resolution and the recordable object depth range, obtainable with parallel, toed-in and sliding aperture camera configurations for multiview image acquisition in the three-dimensional imaging systems, are found by assuming that the camera lens resolution is diffraction limited and the resolution of the recorded image is limited by a pixel pitch of the imaging sensor. The depth resolution for the holographic image is calculated and compared with that of the multiview images for the same parameter values. The influence of the viewer's eye resolution limit on the depth resolution of the multiview images and hologram is also found.

Algorithms↗

PubMed2006

Rapid detection and identification of clinically important bacteria by high-resolution melting analysis after broad-range ribosomal RNA real-time PCR.

BACKGROUND: Broad-range PCR provides valuable information for detecting bacterial infections. This study assesses the combined use of broad-range real-time PCR and high-resolution melting analysis for rapid detection and identification of clinically important bacteria. METHODS: We subjected 46 bacterial culture colonies representing 25 clinically important bacterial species to LightCycler real-time PCR amplification of the 16S rRNA gene in the presence of LCGreen I fluorescent dye. We performed high-resolution melting analysis of the PCR products with the HR-1 instrument and used melting profiles as molecular fingerprints for bacterial species identification. We validated this method via assessment of 54 consecutive bacteria culture colonies obtained from a clinical microbiology laboratory. RESULTS: The 16S rRNA gene of all 25 bacterial species was amplifiable by this method, with PCR product lengths of 216 or 217 bp. Of the 25 bacterial species, we identified 11 via a 1-step post-PCR high-resolution melting analysis. The remaining bacterial species were identified via the high-resolution melting plots obtained by heteroduplex formation between the PCR products of the tested and reference bacterial species or by a 2nd real-time PCR targeting a different region of the 16S rRNA gene. A high-resolution melting database and a working protocol were established for identifying these 25 bacterial species. In the validation assay, a 94% accuracy rate was achieved when the bacterial species were in the high-resolution melting database. CONCLUSIONS: This assay requires no multiplexing or hybridization probes and provides a new approach for bacterial species identification in a molecular diagnostic laboratory.

Bacteria↗

PubMed2006

High-resolution CT findings of 77 patients with untreated pulmonary paracoccidioidomycosis.

OBJECTIVE: The objective of our study was to describe the high-resolution CT findings of 77 patients with pulmonary paracoccidioidomycosis (PCM) who had not yet been treated for PCM. MATERIALS AND METHODS: The high-resolution CT scans of 77 consecutive patients with proven pulmonary PCM were reviewed by two chest radiologists, and decisions regarding the CT findings were reached by consensus. Seventy-one of the patients were men and six were women, with an average age of 49 years. The criteria for interpretation of the high-resolution CT scans are defined in the Fleischner Society's Glossary of Terms. RESULTS: The most frequent high-resolution CT findings were ground-glass attenuation areas (58.4%), small centrilobular nodules (45.5%), cavitated nodules (42.9%), large nodules (41.6%), parenchymal bands (33.8%), areas of cicatricial emphysema (33.8%), interlobular septal thickening (31.2%), and architectural distortion (29.9%). Most of these high-resolution CT findings predominated at the periphery (53%) and posterior (88%) regions involving all lung zones, with discrete predominance in the middle zones (35%). CONCLUSION: The high-resolution CT findings of patients with pulmonary PCM who have not yet been treated consist of ground-glass attenuation areas associated with small centrilobular nodules, cavitated nodules, large nodules, parenchymal bands, and areas of cicatricial emphysema. These abnormalities are usually distributed in the posterior and peripheral regions of the lungs, with discrete predominance in the middle lung zones.

Adult↗

PubMed1984

Patient exposure requirements for high contrast resolution in digital radiographic systems.

The contrast resolution of modern digital radiographic equipment is primarily limited by quantum mottle. The derivation of the contrast resolution of a system as a function of radiation exposure is presented. Calculations based on this derivation show that achieving 0.8% contrast resolution (128 meaningful gray levels) with 1-mm spatial resolution may require a patient exposure of 1.7 rad (1.7 cGy) per image of a thick body part (20 cm tissue). Acceptable clinical studies often can be obtained with only 5% contrast resolution (20 meaningful shades of gray), but even this level of contrast may require a patient exposure of nearly 90 mrad (0.9 mGy) per image. A comparison of three commonly used methods of reducing patient radiation exposure (pulsed imaging, temporal averaging, and recursive filtering) shows that, in theory, a pulsed system achieves the highest contrast resolution for the same total exposure.

Computers↗

PubMed1997

Plain radiographs and thoracic high-resolution CT in patients with ankylosing spondylitis.

OBJECTIVE: The aims of this study were to identify the spectrum of abnormalities seen on high-resolution CT in patients with ankylosing spondylitis and to compare our findings with reports of plain film pulmonary manifestations of the disease. SUBJECTS AND METHODS: We prospectively studied 26 patients with documented ankylosing spondylitis. All patients underwent plain chest radiography (posteroanterior and lateral views), thoracic helical CT, high-resolution CT, and pulmonary function tests. RESULTS: High-resolution CT revealed abnormalities in 18 patients (69%), whereas plain chest radiography revealed abnormalities in four patients (15%). The most common abnormalities seen on CT were interstitial lung disease (ILD) (n = 4), bronchial wall thickening and bronchiectasis (n = 6), paraseptal emphysema (n = 3), mediastinal lymphadenopathy (n = 3), tracheal dilatation (n = 2), and apical fibrosis (n = 2). CONCLUSION: This study, which describes high-resolution CT findings in patients with ankylosing spondylitis, reveals a spectrum of abnormalities unlike those described in previous reports in which researchers used plain chest radiographs as the sole imaging technique. In addition to apical fibrosis, high-resolution CT revealed nonapical ILD, bronchiectasis, paraseptal emphysema, and tracheobronchomegaly. Of these new findings, we believe that identification of ILD is the most important. We suggest that nonapical ILD should be actively sought as an explanation for pulmonary symptoms developing in patients with ankylosing spondylitis. High-resolution CT should form an integral part of such workup.

Adult↗

PubMed1998

Accuracy of high-resolution CT in diagnosing lung diseases.

OBJECTIVE: The purpose of our study was to determine if high-resolution CT facilitates the diagnoses of three diseases that cause cystic air spaces in the lungs: pulmonary eosinophilic granuloma, pulmonary lymphangiomyomatosis, and emphysema. MATERIALS AND METHODS: Retrospective review of high-resolution CT findings in patients with pathologically proven pulmonary eosinophilic granuloma (n = 10), pulmonary lymphangiomyomatosis (n = 9), and emphysema (n = 10) and five control patients without cystic air spaces was conducted by two thoracic radiologists unaware of the pathologic diagnosis. After reviewing the scans, the radiologists made a diagnosis and indicated their level of confidence in the diagnosis on a three-point scale. RESULTS: High-resolution CT allowed the two radiologists to be confident of the diagnosis of pulmonary eosinophilic granuloma in 84% of CT scans, lymphangiomyomatosis in 79%, and emphysema in 95%. When confident, the observers were correct in 100% of the cases. Agreement between observers was good for confident diagnoses based on high-resolution CT scans of pulmonary eosinophilic granuloma (kappa = .77), lymphangiomyomatosis (kappa = .88), and emphysema (kappa = 1). Distribution of cystic changes differed on high-resolution CT scans for lymphangiomyomatosis and pulmonary eosinophilic granuloma. No consistent distribution pattern was observed for emphysema. Lack of a perceptible cyst wall was unique to cases of emphysema. All patients with lymphangiomyomatosis lacked nodules in the intervening lung parenchyma, whereas most patients with pulmonary eosinophilic granuloma had parenchymal nodules. CONCLUSION: High-resolution CT can help radiologists reliably diagnose pulmonary eosinophilic granuloma, lymphangiomyomatosis, and emphysema.

Adult↗

PubMed2004

Simultaneous bilateral breast and high-resolution axillary MRI of patients with breast cancer: preliminary results.

OBJECTIVE: The aims of this study were to develop a standardized one-step procedure for simultaneous high-resolution MRI of the axilla and bilateral breast MRI and to identify nodal features suggestive of metastatic involvement. SUBJECTS AND METHODS. We studied 16 women undergoing axillary lymph node dissection after combined bilateral breast MRI and high-resolution MRI of the axilla with a maximum in-plane resolution of 0.6 x 0.4 mm. MRI was performed using a standard double breast coil and a 15-cm round flexible surface coil adapted to the axilla. High-resolution axillary sequences, including inversion recovery T2- and spin-echo T1-weighted sequences, were performed before and after gadolinium chelates bolus injection. Axillary image analysis focused on nodal morphology including size, contour regularity, cortex and hilar appearance, signal intensity, and enhancement parameters. Axillary MRI findings were compared with the final pathogic results from axillary lymph node dissection in all patients. Patients were divided into groups according to the final pathologic axillary status. Differences in MRI lymph node features across the groups were tested using a t test for quantitative data and the chisquare test or Fisher's exact test for binary data. RESULTS: The features of the axilla on high-resolution MRI that best discriminated between patients with positive pathologic findings and those with negative pathologic findings were the presence of nodes with irregular contours (p < 10(-4)), high signal intensity on T2 sequences (p < 10(-3)), marked gadolinium enhancement (p < 10(-3)), and round hila and abnormal cortexes (p < 0.05). CONCLUSION: Breast tissue and axillary lymph nodes both can be analyzed on MRI in a one-step process using a bilateral breast coil combined with a surface coil. Morphologic features observed on high-resolution MRI of the axilla can improve the identification of metastatic nodes.

Adult↗