An unusual presentation of usual-type endocervical adenocarcinoma with lobular endocervical glandular hyperplasia: A case report.

Uterine cervical hematoma is rare. A 51-year-old woman underwent pelvic magnetic resonance imaging (MRI) for uterine tumor survey. A large hematoma with cystic and solid lesions was observed in the uterine cervix. Follow-up MRI after 5 days revealed that the hematoma had decreased in volume. Pathological examination after surgery suggested there was usual-type endocervical adenocarcinoma (UEA) in the lower cervix and lobular endocervical glandular hyperplasia (LEGH) in the upper cervix, along with the cervical hematoma. The findings of this case suggest that the uterine cervical hematoma was secondary to either UEA or LEGH.

Posterior lumbar subcutaneous edema as the rare sign of IgA vasculitis (Henoch-Schönlein purpura): A case of a child.

Posterior lumbar subcutaneous edema (PLSE) is often found on MRI in adults with obesity or various lumbar conditions. We report a case of a 6-year-old boy with IgA vasculitis (Henoch-Schönlein purpura) along with PSLE observed on CT and MRI. The finding is markedly rare in patients with IgA vasculitis, with only limited cases previously reported in the literature. The edema was symmetrically localized along the erector spine muscle with a smooth margin. These findings differed from the irregularly accumulated edema observed in some adult cases. PLSE should not be overlooked as a nonspecific finding. When symmetrical and circumscribed PLSE is found in children, IgA vasculitis should be added to differential diagnosis in PLSE.

Neurovascular decompression of the rostral ventrolateral medulla decreases blood pressure and sympathetic nerve activity in patients with refractory hypertension.

Recently, the authors experienced four patients who had refractory hypertension and neurovascular compression of the rostral ventrolateral medulla (RVLM). One of them, a 49-year-old woman, had undergone continuous intravenous drip injections of calcium channel blockers and ß-blockers for more than 3 years because of severe and refractory hypertension. The patients had undergone microvascular decompression (MVD) of the RVLM, and the changes in blood pressure (BP) and sympathetic nerve activities were recorded. In these patients, BP decreased to the normal range without any antihypertensive drugs 2 to 3 months after MVD. The tibial sympathetic nerve activities under resting and stress conditions significantly decreased, and plasma levels of norepinephrine, urinary levels of adrenaline, and plasma renin activity were also significantly decreased after MVD of RVLM. In some patients with refractory hypertension, arterial compression of the RVLM enhances sympathetic nerve activity and renin-angiotensin system to thereby increase BP. In these patients, the operative decompression of the RVLM could lower BP via restoration of sympathetic nerve activities and the renin-angiotensin system.

Fiber-tracking techniques can predict the degree of neurologic impairment for periventricular leukomalacia.

OBJECTIVE: Preterm or low birth weight infants display a greater propensity for white matter injury caused by hypoxic-ischemic encephalopathy in the perinatal period. Such episodes can result in periventricular leukomalacia, which may substantially influence later brain development. Noninvasive methods of assessing the severity of injury at the earliest stage of life have not yet been established. METHODS: We used diffusion tensor imaging to evaluate sensorimotor fibers in periventricular leukomalacia. Region-of-interest measurements and tractography-based measurements were performed for 10 patients with periventricular leukomalacia. The mean age of the patients was 19 +/- 9.5 months (range: 9-41 months). Motor functions were assessed at a mean age of 28 +/- 14.5 months. RESULTS: Measured fractional anisotropy values of the motor tract were significantly higher in all mild periventricular leukomalacia cases than in severe cases. A fractional anisotropy cutoff value of <0.5 was useful for predicting severe periventricular leukomalacia. Region-of-interest measurements were less sensitive, compared with tractography-based measurements. CONCLUSIONS: Fiber-tracking techniques can provide information on the pathophysiologic features of motor disability in patients with periventricular leukomalacia. Early screening of patients with a history of asphyxia may facilitate early intervention (eg, rehabilitation), to achieve better motor function.

The pyramidal tract has a predictable course through the centrum semiovale: a diffusion-tensor based tractography study.

PURPOSE: To identify reproducible anatomical landmarks that would allow predicting the course of the pyramidal tract (PT) through centrum semiovale. MATERIALS AND METHODS: A total of 20 normal volunteers (12 males, eight females) with a mean age of 34 years (range, 20-59 years) were scanned using a 1.5-Tesla clinical MR unit to assess the trajectory of the PT. Neuroanatomical characteristics of the PT passing through the centrum semiovale were assessed by two independent observers. Tractography data of 10 consecutive patients with brain tumor were used to test the precision of anatomy-based prediction of the tract location. RESULTS: On sagittal view, 95% of the PT depicted on tractography displayed a completely straight or primarily straight course through the supratentorial brain. In 98% of tracts, the bending point of the PT was identified < or = 3 mm from the level of the anterior commissure-posterior commissure (AC-PC) plane. In 80% of PT, the intersection with the AC-PC plane occurred midway between the AC and the PC as seen on the sagittal view. Evaluation of the PT in 10 patients with brain tumor revealed that the anatomy-based prediction of PT on the contralesional hemisphere was not substantially deviated from the actual tractography depicted PT. PT on the lesional hemispheres, however, had deviations of various degrees. CONCLUSION: The course of the PT through supratentorial brain can be predicted based on easily identifiable landmarks. This anatomy-based prediction can be clinically applied for cases without substantial mass effect from a space occupying lesion.

Somatotopic organization of thalamocortical projection fibers as assessed with MR tractography.

PURPOSE: To prospectively evaluate the course of sensory fibers through the supratentorial brain with diffusion-tensor-based tractography. MATERIALS AND METHODS: This study was approved by the institutional review board. Informed consent was obtained. Seven healthy volunteers (five men, two women; age range, 20-55 years) underwent 1.5-T magnetic resonance imaging. Diffusion-tensor images with isotropic voxels (2 x 2 x 2 mm) were obtained by using a single-shot echo-planar imaging technique, with a motion-probing gradient in 15 orientations, a b value of 1000 sec/mm(2), and nine signals acquired. The total imaging time was approximately 30 minutes. Fiber tracking of the sensorimotor pathways was performed with the fiber assignment by continuous tracking method. RESULTS: All the pyramidal tracts rotated anteriorly as they traveled through the centrum semiovale. On the other hand, the sensory tracts rotated posteriorly as they coursed through the centrum semiovale toward the cortex. When the sensorimotor tracts were viewed as a unit, the tracts of the lower extremity formed the axis of rotation around which the other parts of the pyramidal and sensory homunculus rotated. CONCLUSION: Sensorimotor fibers of the lower extremity form an axis of rotation, around which the pyramidal fibers rotate anteriorly and the sensory fibers rotate posteriorly.

Diagnosis of breast tumors by contrast-enhanced MR imaging: comparison between the diagnostic performance of dynamic enhancement patterns and morphologic features.

PURPOSE: To compare the diagnostic performance of breast lesions by the enhancement patterns and morphologic criteria on magnetic resonance imaging (MRI). MATERIALS AND METHODS: Both T1-weighted 3D gradient-echo sequences with high temporal resolution and high-spatial-resolution MRI were performed on 190 patients with a total of 204 enhancing lesions (144 malignant and 60 benign). The enhancement patterns and morphologic features of each mass and nonmass lesion were analyzed, and the diagnostic performance was compared. RESULTS: The sensitivity and specificity of the morphologic criteria were statistically significantly higher than those of the enhancement patterns (sensitivity: P = 0.0012, specificity: P = 0.0003), and the A(z) values for the three observers were 0.900, 0.919, and 0.900. The diagnostic accuracy of the morphologic criteria for both types of lesions was superior, and the differences were statistically significant (mass: P = 0.0001, nonmass: P = 0.0389). CONCLUSION: The analysis of the morphologic features of enhancing breast lesions alone showed higher diagnostic performance; therefore, signal intensity (SI) time-course data may not be needed to diagnose malignant breast lesions.

Oculomotor nerve palsy evaluated by diffusion-tensor tractography.

INTRODUCTION: The aim of the study was to test the feasibility of the tractography technique based on diffusion-tensor imaging (DTI) for the assessment of small infarcts involving the brainstem. METHODS: A patient who presented with an isolated left third cranial nerve palsy underwent magnetic resonance examination. Images were obtained by use of a whole-body, 1.5-T imager. Data were transferred to an off-line workstation for fiber tracking. RESULTS: The conventional diffusion-weighted imaging (DWI) performed using a 5 mm slice thickness could only depict an equivocal hyperintensity lesion located at the left paramedian midbrain. An additional thin-slice DTI was performed immediately after the initial DWI using a 3 mm slice thickness and was able to delineate the lesion more clearly. Image postprocessing of thin-slice DTI data revealed that the lesion location involved the course of the third cranial nerve tract, corresponding with the patient's clinical symptoms. CONCLUSION: The tractography technique can be applied to assess fine neuronal structures of the brainstem, enabling direct clinicoradiological correlation of small infarcts involving this region.

High-resolution imaging of the spine using multidetector-row computed tomography: differentiation between benign and malignant vertebral compression fractures.

OBJECTIVE: The purpose of this study was to investigate the ability of high-resolution computed tomography (CT) images to distinguish between benign and malignant vertebral compression fractures. METHODS: Computed tomography images of 45 benign compression fractures in 40 patients and 33 malignant compression fractures in 33 patients were evaluated. A 16-slice multidetector-row CT scanner was used for data acquisition, and axial images with a slice thickness of 1 mm and sagittal and coronal multiplanar reconstruction images with a slice thickness of 0.7 to 1 mm were used for interpretation. RESULTS: The following findings were significantly more frequent in malignant fractures: destruction of the anterolateral and/or posterior cortex of the vertebral body, destruction of the cancellous bone of the vertebral body, destruction of the end plate, destruction of the pedicle, a paraspinal soft tissue mass, and an epidural mass. The extremely reliable signs of malignancy were destruction of the anterolateral and/or posterior cortex of vertebral body (100% accuracy) and destruction of the cancellous bone of the vertebral body (97.4% accuracy). CONCLUSION: High-resolution CT can provide many useful signs for differentiating between benign and malignant vertebral compression fractures, and its diagnostic ability is sufficient for clinical use.

Higher lesion conspicuity for SENSE dynamic MRI in detecting hypervascular hepatocellular carcinoma: analysis through the measurements of liver SNR and lesion-liver CNR comparison with conventional dynamic MRI.

The aim of our study was to compare the signal-to-noise ratio (SNR) of liver parenchyma and the contrast-to-noise ratio (CNR) of hypervascular hepatocellular carcinoma (HCC) between conventional and SENSE dynamic MRI. Thirty-one consecutive patients who were strongly suspected of having HCC were enrolled in our study. The subjects consisted of 20 men and 11 women aged 52 years to 79 years (mean 66.8 years). Dynamic MRI was performed for each patient, with SENSE (SENSE MRI) and without SENSE (conventional MRI) on separate days. For the quantitative analysis, the liver SNR and the lesion-liver CNR of 25 hypervascular HCCs detected on both conventional and SENSE dynamic MRI were measured. The liver SNR of the arterial phase and the portal venous phase was 84.1+/-24.7 and 104.7+/-34.3, respectively, in conventional MRI, while it was 62.9+/-19.5 and 44.5+/-18.2, respectively, in SENSE MRI. SENSE MRI showed a statistically significantly lower SNR than conventional MRI (P<0.01). The lesion-liver CNR was 26.3+/-15.9 in conventional MRI and 39.0+/-19.6 in SENSE MRI. The lesion-liver CNR in SENSE MRI was significantly higher than in conventional MRI (P<0.01). The SNR in SENSE MRI is significantly lower than in conventional MRI, although the lesion CNR is significantly higher than in conventional MRI.

Relationship between contrast enhancement on fluid-attenuated inversion recovery MR sequences and signal intensity on T2-weighted MR images: visual evaluation of brain tumors.

PURPOSE: To investigate the relationship between the degree of contrast enhancement in fluid-attenuated inversion recovery (FLAIR) sequences and tumor signal intensity on T2-weighted images. MATERIALS AND METHODS: A total of 96 patients suspected of having brain tumors were examined by MR imaging, and whenever a brain tumor with an enhancing part larger than the slice thickness was demonstrated on postcontrast T1-weighted images, postcontrast FLAIR images were additionally acquired. The tumor signal intensity on the T2-weighted images was visually classified as follows: equal or lower compared with normal cerebral cortex (group 1), higher than normal cortex (group 2), and as high as cerebrospinal fluid (CSF) (group 3). When a lesion contained several parts with different signal intensities on T2-weighted images, we assessed each part separately. In each group, we visually compared pre- and postcontrast FLAIR images and assessed whether tumor contrast enhancement was present. When contrast enhancement was present on FLAIR sequence, the degree of contrast enhancement in T1-weighted and FLAIR sequences was visually compared. RESULTS: Postcontrast T1-weighted images showed 46 enhancing lesions, including 48 parts, in 31 MR examinations. FLAIR images of the lesion-parts in group 1 (N=18) did not show significant contrast enhancement. In group 2 (N=12), all the parts were enhanced in FLAIR sequences, and three parts were enhanced more clearly in the FLAIR sequences than in the T1-weighted sequences. In group 3 (N=18), all the parts were enhanced equally or more clearly in the FLAIR sequences than in the T1-weighted sequences. CONCLUSION: The signal intensity in FLAIR sequences is largely influenced by both T1 and T2 relaxation time; there is a close relationship between the signal intensity of brain tumors on T2-weighted images and the degree of contrast enhancement on FLAIR sequences. When tumors have higher signal intensity than normal cortex on T2-weighted images, additional postcontrast FLAIR imaging may improve their depiction.

Diagnosis of Alzheimer's disease using brain perfusion SPECT and MR imaging: which modality achieves better diagnostic accuracy?

PURPOSE: The purpose of this study was to compare the accuracy of MR imaging and brain perfusion single-photon emission tomography (SPECT) in diagnosing Alzheimer's disease (AD). METHODS: The transaxial section display of brain perfusion SPECT, three-dimensional stereotactic surface projection (3D-SSP) SPECT image sets, thin-section MR imaging of the hippocampus and perfusion MR imaging were evaluated in 66 subjects comprising 35 AD patients and 31 subjects without AD. SPECT and MR imaging were visually interpreted by two experts and two novices, and the diagnostic ability of each modality was evaluated by receiver operating characteristic (ROC) analysis. RESULTS: In the experts' interpretations, there was no significant difference in the area under the ROC curve (Az) between 3D-SSP and thin-section MR imaging, whereas the Az of transaxial SPECT display was significantly lower than that of 3D-SSP (3D-SSP: 0.97, thin-section MR imaging: 0.96, transaxial SPECT: 0.91), and the Az of perfusion MR imaging was lowest (0.63). The sensitivity and specificity of each modality were, respectively, 80.0% and 96.8% for 3D-SSP, 77.1% and 96.8% for thin-section MR imaging, 60.0% and 93.5% for transaxial SPECT display and 34.3% and 100% for perfusion MR imaging. In the novices' interpretations, the Az, sensitivity and specificity of 3D-SSP were superior to those of thin-section MR imaging. CONCLUSION: Thin-section hippocampal MR imaging and 3D-SSP image sets had potentially equivalent value for the diagnosis of AD, and they were superior to transaxial SPECT display and perfusion MR imaging. For avoidance of the effect of interpreters' experience on image evaluation, 3D-SSP appears to be optimal.

Effect of thin-section diffusion-weighted MR imaging on stroke diagnosis.

BACKGROUND AND PURPOSE: Diffusion-weighted (DW) imaging has limited spatial resolution, especially in the z direction. We decreased the section thickness of DW imaging to 3 mm to determine if this change improves the depiction of small infarcts and if it affects stroke diagnosis. METHODS: We studied conventional (5-mm section thickness, 1-mm intersection gap) and thin-section (3-mm section thickness, no intersection gap) DW imaging data in 49 patients with symptoms of acute cerebral ischemia. Two radiologists who were not aware of the clinical findings reviewed all images and diagnosed the stroke subtype according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) method. Accuracies of stroke diagnosis with an experienced neuroradiologist and with a second-year radiology resident were compared. To quantify lesion conspicuity, contrast-to-noise ratios (CNRs) were measured. The CNR of thin-section DW imaging was then divided by the CNR of conventional DW imaging to yield the relative CNR (rCNR). RESULTS: The experienced neuroradiologist made the correct final diagnoses in 78% of cases with conventional DW imaging, improving to 100% with thin-section DW imaging. The resident made the correct diagnoses in 71% of cases with conventional DW imaging, improving to 94% with thin-section DW imaging. Lesion conspicuity was improved on thin-section DW imaging (rCNR = 1.47 +/- 0.63), especially for supratentorial lesions (rCNR = 1.51 +/- 0.63). CONCLUSION: Compared with conventional DW imaging, thin-section DW imaging permitted better lesion conspicuity and more precise stroke diagnosis.

Tractography for arteriovenous malformations near the sensorimotor cortices.

We sought to use diffusion-tensor imaging-based tractography to assess the relationship between the arteriovenous malformations (AVM) and the sensorimotor cortices/tracts. Three patients who had an AVM closely situated to the sensorimotor tracts were studied. The relationship between the sensorimotor tracts and the AVM was well demonstrated in all patients. Tractography was also helpful in identifying the location of the motor cortex in some of the cases.

Stroke patients' evolving symptoms assessed by tractography.

PURPOSE: To test the hypothesis that an interval evolution in the location of the depicted sensorimotor tract relative to the infarct (the "tract-infarct relationship") may be related to stroke victims' symptom progression. MATERIALS AND METHODS: Patients (N = 7) who underwent multiple diffusion-tensor imaging (DTI) studies during symptomatic progression were included in this study. DTI was performed using a single-shot echo-planar imaging (EPI) technique with a motion-probing gradient in six orientations, a b-value of 800 seconds/mm2, and six image averages. The total scan time was four minutes and 24 seconds. Fiber-tracking of the sensorimotor pathways was performed, and the locations of these tracts were retrospectively assessed in relation to the evolution of the symptoms. RESULTS: Five of the seven patients showed an interval enlargement of the infarct on diffusion-weighted (DW) images. In two of these cases the lesion enlarged to involve the sensorimotor tracts, while in three cases the lesion enlarged only so far to come into close proximity to the sensorimotor tract. In the remaining two cases there was no interval enlargement of the infarct, and therefore the tract-infarct relationship could not account for the evolution of the symptoms in these cases. CONCLUSION: A tract-infarct relationship can be observed with the use of a fiber-tracking technique, and the results may improve our understanding of the symptom progression seen in stroke victims.

Do white matter changes have clinical significance in Alzheimer's disease?

BACKGROUND: Although white matter changes visible with MRI are generally considered to result from ischemia, it has become clear that these changes also appear in patients with Alzheimer's disease (AD). However, their significance in AD is unknown. OBJECTIVE: We evaluated the clinical significance of white matter changes in AD. METHODS: Ninety-six AD patients (79.4 +/- 5.92 years old) and 48 age-matched control subjects (80.0 +/- 7.03 years old) participated in the study. Three neuroradiologists assessed the degree of periventricular hyperintensities (PVH) and deep white matter hyperintensities (DWMH) using a modified Fazekas' rating scale. We examined whether there was a difference in the severity and the histogram pattern of the white matter changes, or in vascular factors (hypertension, diabetes mellitus, and ischemic heart disease) between the two groups. We also analyzed the association between the severity of the white matter changes and the degree of dementia (MMSE score and disease duration). RESULTS: There were no differences in the vascular factors between AD and control subjects. The degree of PVH in AD was severe compared with that in the control subjects. In histograms of the number of subjects with each degree of PVH severity, the distribution of AD patients had peaks at both the low and intermediate degrees of PVH, while most of the controls had a low degree of PVH. There was no difference in the degree or the histogram pattern of DWMH between the two groups. The severity of white matter changes was not associated with severity of dementia in AD. CONCLUSIONS: Although PVH might have several causative factors, and may have some clinical significance, the change itself does not contribute to the progression of AD.

Fiber-tracking method reveals sensorimotor pathway involvement in stroke patients.

BACKGROUND AND PURPOSE: We tested the feasibility of a new MRI technique that provides visualization of the sensorimotor tracts in vivo in a group of stroke victims. SUMMARY OF REPORT: Fourteen patients with small infarctions involving the white matter of the supratentorial brain were evaluated. Sensorimotor tracts on the lesional and contralesional sides were successfully depicted in all cases. The position of the sensorimotor tracts relative to the infarct was in good agreement with clinical symptoms. The overall sensitivity and specificity for sensorimotor tract involvement were 100% and 77%, respectively. CONCLUSIONS: Our proposed fiber-tracking method was shown to be a clinically feasible technique that correlates well with clinical symptoms.