We report radiological findings of ultrasonography (US), 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) computed tomography (CT), and magnetic resonance (MR) imaging for a rare case of skeletal muscle metastasis from an underlying known malignant phyllodes tumor. To our knowledge, there has been no previous published report of imaging findings of skeletal muscle metastasis from a sarcoma such as malignant phyllodes tumor.
Magnetic Resonance Spectroscopy ; Muscle, Skeletal ; Neoplasm Metastasis ; Phyllodes Tumor ; Positron-Emission Tomography ; Sarcoma

Embryonal rhabdomyosarcoma of the head and neck is very rare in adults. We report a case of embryonal rhabdomyosarcoma in the nasal cavity, occuring in a 24-year-old male patient presenting with left nasal obstruction, ipsilateral eye and cheek pain and multiple neck nodules. Rhabdomyosarcoma should be considered in the differential diagnosis of poorly defined soft tissue mass of the nasal cavity not only in children, but also in adults.
Adult ; Cheek ; Child ; Diagnosis, Differential ; Eye ; Head ; Humans ; Male ; Nasal Cavity ; Nasal Obstruction ; Neck ; Rhabdomyosarcoma ; Rhabdomyosarcoma, Embryonal ; Young Adult

Primary localized amyloidosis of the ureter and bladder is a very rare condition. CT and cystoscopic findings are indistinguishable from malignant neoplasm or inflammatory lesions. We report a case of unilateral distal ureteral thickening caused by primary localized amyloidosis. MR image features of hypointensity on T2-weighted images and mural enhancing pattern on contrast enhanced T1-weighted images can be helpful for diagnosis of ureteral amyloidosis.
Amyloidosis ; Ureter ; Urinary Bladder

Granulocytic sarcoma is a rare extramedullary tumor composed of immature granulocytic precursors. Usually, granulocytic sarcoma is seen in association with acute myeloid leukemia, or other myeloproliferative disorders. Rarely, it may manifest as a primary presentation before the onset of systemic disease in acute myeloid leukemia. The clinical suspicion of granulocytic sarcoma based on imaging findings is important for the management of the patient especially when systemic disease of acute myeloid leukemia is not confirmed as in our case. We report the MR findings of a granulocytic sarcoma in the left leg mimicking hemorrhagic abscess in a patient with acute myeloid leukemia. We believe that MRI can be a helpful diagnostic method of making a differential diagnosis of granulocytic sarcoma in a patient with leukemia, and this can be done by analyzing the signal intensity and the enhancement pattern.
Abscess ; Diagnosis, Differential ; Humans ; Leg ; Leukemia ; Leukemia, Myeloid, Acute ; Myeloproliferative Disorders ; Sarcoma, Myeloid

PURPOSE: We sought to evaluate enhancement of plaque with gadolinium-based contrast agent by magnetic resonance imaging (MRI) in comparison with histopathology, namely lipid-rich and macrophage-rich components that were two representative characteristics of plaque vulnerability using atherosclerotic rabbit aorta in order to determine which histopathologic component is relevant to the enhancement. MATERIALS AND METHODS: New Zealand white rabbit (n=4, weight 3.0 to 3.5 kg, all male) was used for animal model of atherosclerosis. Atherosclerotic aortic lesions were induced by high-cholesterol diet and double balloon injury. T1-weight axial images were acquired before and after gadolinium-based contrast agent using a 3-T MRI. MR images and the matched histopathological sections (n=35) were divided into 4 quadrants or 3 (n=130). Enhancement ratio (ER, ER=SIpost/SIpre) on MRI was calculated for each quadrant and compared with histopathology in regard to lipid-rich and macrophage-rich areas. RESULTS: Lipid-rich quadrants were 72 and fibrous quadrants were 58. The number of quadrants which had macrophage-rich areas was 105 and that of quadrants which did not have macrophage-rich areas was 25. ER was significantly higher in lipid-rich quadrants than in fibrous quadrants (mean ER 2.25+/-0.41 vs. 2.72+/-0.65, p=0.013). ER poorly correlated with macrophage-rich areas when lipid-component was controlled (correlation coefficient -0.203, p=0.236). CONCLUSION: Lipid-rich plaques showed stronger enhancement than fibrous plaques using a standard gadolinium-based extracellular contrast agent. Macrophage infiltration did not correlate with degree of enhancement. Further study is warranted that account for optimal time of imaging after contrast injection using various plaque models from early to advanced stages and all possible parameters associated with contrast enhancement.
Aorta ; Atherosclerosis ; Diet ; European Continental Ancestry Group ; Humans ; Macrophages ; Magnetic Resonance Imaging ; Magnetic Resonance Spectroscopy ; Magnetics ; Magnets ; Models, Animal ; New Zealand ; Plaque, Atherosclerotic ; Rabbits

PURPOSE: To evaluate the characteristic MR imaging findings of Langerhans cell histiocytosis (LCH) in the skull and to compare them with those of plain radiography and computed tomography. MATERIALS AND METHODS: A total of 10 lesions in 9 patients (Age range; 5-42 years, Mean age; 18, all women) with Langerhans cell histiocytosis in the skull were included in our study. Nine lesions in nine patients were histologically confirmed by surgery or fine needle aspiration biopsy. All patients performed with MRI, and plain radiography and CT scan were done in 7 patients (8 lesions). Two experienced neuroradiologists reviewed the radiological examinations independently with attention to location, size, shape and nature of the lesions in the skull and compared the extent and extension of the lesions to adjacent structures. RESULTS: The lesions were distributed in all of the skulls without predilection site. On MRI, the masses were shown as well-enhancing soft tissue masses (10/10) mainly in diploic spaces (8/10) with extension to scalp (9/10) and dura mater (7/10). Dural enhancement (7/10) and thickening (4/10) were seen. The largest diameter of the soft tissue masses ranged 1.1 cm to 6.8 cm, shaped as round (5/10) or oval (5/10). On CT scans, the lesions were presented as soft tissue masses involving diploic space (6/8) and scalp extension (7/8) were also well visualized. Although bony erosion or destruction was more clearly seen on CT rather than those of MRI, enhancement of soft tissue masses and dura were not well visualized on CT. In contrast, all of the lesions in LCH were seen as punched out (4/8), beveled-edge appearance (4/8) osteolytic masses in plain radiography, but scalp and dural extension could not be seen. CONCLUSION: Characteristic MR findings in patients with LCH are soft tissue mass in diploic space with extension to dura and scalp, and MRI would be better imaging modality than plain radiography or CT .
Biopsy ; Biopsy, Fine-Needle ; Dura Mater ; Histiocytosis, Langerhans-Cell ; Humans ; Scalp ; Skull

PURPOSE: To investigate the effects of various intracranial volume (ICV) measurement methods on the sensitivity of hippocampal volumetry and modulated voxel-based morphometry (mVBM) in female patients with major depressive disorder (MDD). MATERIALS AND METHODS: T1 magnetic resonance imaging (MRI) data for 41 female subjects (21 MDD patients, 20 normal subjects) were analyzed. Hippocampal volumes were measured manually, and ICV was measured manually and automatically using the FreeSurfer package. Gray and white matter volumes were measured separately. RESULTS: Manual ICV normalization provided the greatest sensitivity in hippocampal volumetry and mVBM, followed by FreeSurfer ICV, GWMV, and GMV. Manual and FreeSurfer ICVs were similar in normal subjects (p = 0.696), but distinct in MDD patients (p = 0.000002). Manual ICV-corrected total gray matter volume (p = 0.0015) and Manual ICV-corrected bilateral hippocampal volumes (right, p = 0.014; left, p = 0.004) were decreased significantly in MDD patients, but the differences of hippocampal volumes corrected by FreeSurfer ICV, GWMV, or GMV were not significant between two groups (p > 0.05). Only manual ICV-corrected mVBM analysis was significant after correction for multiple comparisons. CONCLUSION: The method of ICV measurement greatly affects the sensitivity of hippocampal volumetry and mVBM. Manual ICV normalization showed the ability to detect differences between women with and without MDD for both methods.
Depressive Disorder, Major ; European Continental Ancestry Group ; Female ; Hippocampus ; Humans ; Magnetic Resonance Imaging

PURPOSE: Craniospinal neurenteric (NE) cysts are rare developmental non-neoplastic cysts of the central nervous system with diverse MR imaging findings. The purpose of this study was to evaluate various MR imaging findings of intracranial and intraspinal NE cysts. MATERIALS AND METHODS: We retrospectively reviewed the MR imaging findings of six NE cysts that were confirmed by pathology. We evaluated anatomic location, signal intensity, size and enhancement pattern of NE cysts. RESULTS: Two intracranial lesions were located extra-axially in the cerebellopontine angle and quadrigeminal cisterns. Three spinal lesions were intraduralextramedullary cysts, located ventral to the spinal cord, but one thoracic lesion was an intramedullary cyst. The signal intensity of the cysts was hyperintense on T1-weighted images as compared with the cerebrospinal fluid (CSF) for two intracranial lesions and one cervical lesion. In addition, all intracranial lesions showed diffusion restriction. For the remaining three spinal lesions, the signal intensity was nearly the same as the signal intensity of the CSF as seen on both T1- and T2-weighted images. On contrast-enhanced studies, two intracranial cysts showed a small nodular enhancement and one thoracic spinal lesion showed rim enhancement. CONCLUSION: NE cysts have various locations, signal intensities, and possible focal nodular or rim enhancement. Therefore, NE cysts can be included in the differential diagnosis of various craniospinal cystic or tumorous cystic lesions.
Central Nervous System ; Cerebellopontine Angle ; Diagnosis, Differential ; Diffusion ; Neural Tube Defects ; Retrospective Studies ; Spinal Cord

PURPOSE: Although it's been known for half a century that unique structures have evolved in the cerebellum and they then became greatly enlarged in the human brain, the function of these structures still remains unknown. The purpose of this study was to assess cerebellar activation during motor, sensory, word generation, listening comprehension, and working memory tasks with using functional magnetic resonance imaging (fMRI). MATERIALS AND METHODS: Eleven healthy right-handed subjects (Male: female, 6:5, mean age: 27.4years) were imaged on a Siemens 1.5T scanner. Whole brain functional maps were acquired using BOLD EPI sequences in the axial plane. Each paradigm consisted of five epochs of activation vs. the control condition. The activation tasks consisted of left finger complex movement, sensory stimulation of the left hand, word generation, listening comprehension, and working memory tasks. The reference function was a boxcar waveform. The activation maps were thresholded at p = 0.001. SPM 5 evaluated the activated areas and responses within the cerebellum. RESULTS: Cerebellar activation was observed on motor task, word generation task, and working memory task. There were 949 activated areas and the mean fitted and adjusted response was 0.68 during the motor task. There were 319 activated areas and the mean fitted and adjusted response was 0.15 during the word generation task. There were 330 activated areas and the mean fitted and adjusted response was 0.26 during the working memory task. CONCLUSION: Our results suggest that the cerebellum is involved in a variety of functional tasks, including motor, word generation, and working memory tasks. However, during the motor task, the cerebellum showed a large activated area and a high response. Cerebellar function can be evaluated by fMRI.
Brain ; Cerebellum ; Comprehension ; Female ; Fingers ; Hand ; Humans ; Magnetic Resonance Imaging ; Memory, Short-Term

PURPOSE: The purpose of this study was to investigate the quantitative evaluation of the corticospinal tract (CST) at the multiple levels by using functional MRI (fMRI) co-registered to diffusion tensor tractography (DTT). MATERIALS AND METHODS: Ten normal subjects without any history of neurological disorder participated in this study. fMRI was performed at 1.5 T MR scanner using hand grasp-release movement paradigm. DTT was performed by using DtiStudio on the basis of fiber assignment continuous tracking algorithm (FACT). The seed region of interest (ROI) was drawn in the area of maximum fMRI activation during the motor task of hand grasp-release movement on a 2-D fractional anisotropy (FA) color map, and the target ROI was drawn in the cortiocospinal portion of anterior lower pons. We have drawn five ROIs for the measurement of FA and apparent diffusion coefficient (ADC) along the corona radiata (CR) down to the medulla. RESULTS: The contralateral primary sensorimotor cortex (SM1) was mainly found to be activated in all subjects. DTT showed that tracts originated from SM1 and ran to the medulla along the known pathway of the CST. In all subjects, FA values of the CST were higher at the level of the midbrain and posterior limb of internal capsule (PLIC) than the level of others. CONCLUSION: Our study showed that co-registered fMRI and DTT has elucidated the state of CST on 3-D and analyzed the quantitative values of FA and ADC at the multiple levels. We conclude that co-registered fMRI and DTT may be applied as a useful tool for clarifying and investigating the state of CST in the patients with brain injury.
Anisotropy ; Brain Injuries ; Diffusion ; Evaluation Studies as Topic ; Extremities ; Hand ; Humans ; Internal Capsule ; Magnetic Resonance Imaging ; Mesencephalon ; Nervous System Diseases ; Pons ; Pyramidal Tracts ; Seeds ; Track and Field