BACKGROUND AND PURPOSE: Basal cell adenomas (BCAs) are rare tumors of the parotid gland. Only a few case reports describing MR imaging features of BCA have been published. The aim of this study was to describe and characterize the MR findings of BCAs of the parotid gland. MATERIALS AND METHODS: ...

BACKGROUND AND PURPOSE: The imaging features of metastatic melanomas are distinctive due to the presence of melanin and the propensity for hemorrhage. Both hemorrhage and melanin can produce T1-weighted hyperintensity and T2*-weighted signal intensity loss. We hypothesized that T2*-weighted images would improve detection of metastatic melanoma. METHODS: The T2* and ...

An 8-year-old Yorkshire terrier developed acute onset coma and seizure after cranial trauma. Intracranial hemorrhage was suspected from the clinical signs and history. Low-field magnetic resonance (MR) imaging revealed a round mass within the right cerebral hemisphere, compressing the right lateral ventricle and displacing the longitudinal fissure to the left. ...

Ring-enhancing lesions seen on MR images can occur with a variety of etiologies. Some ring-enhancing lesions have hypointense rims peripherally on T2-weighted MR images. In this study, we examined whether T2 hypointense rims were associated with specific pathologies. A search for ring-enhancing lesions on MR images obtained from 1996 to ...

The imaging findings (X-ray and MRI) and patterns of calcification of five patients with pathologically proven soft-tissue chondroma were correlated with histopathology. The size ranged from 0.5 to 3 cm. Four showed calcifications: curvilinear, punctuate, mixed curvilinear, and punctuate patterns, and the other one with a dystrophic or homogenous dense ...

OBJECTIVE: We present the MRI features with pathologic correlation of aggressive fibromatosis, incorporating 203 cases over a 5-year period from the Royal Marsden Hospital Sarcoma Unit database. MATERIALS AND METHODS: Sixty patients had imaging available for retrospective review of which 29 had preoperative MRI and final histopathologic diagnosis of aggressive ...

A 69-year-old female presented with a de novo lesion detected incidentally. Computed tomography demonstrated an isodense mass in the left parietal convexity with peritumoral edema, with homogeneous enhancement by contrast medium. Magnetic resonance imaging showed the left parietal convexity tumor as isointense on T(1)-weighted imaging and homogeneously hyperintense on T(2)-weighted ...

BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a ...

PURPOSE: We investigated sequential changes in MRI and relevant histopathological findings after PRC. MATERIALS AND METHODS: A total of 15 rabbits were examined with MRI and sacrificed immediately (3), and 7 (4), 45 (4) and 90 (4) days after PRC. MRI studies were reviewed for the signal intensity of cryolesions ...

Adenoma of the nipple (nipple adenoma) is a rare breast tumor that can show various histologic features. We present magnetic resonance (MR) and other imaging findings of a case of nipple adenoma and correlate them with detailed histologic features of the tumor. The lesion showed early strong enhancement with rim ...

PURPOSE: To prospectively compare oral contrast-enhanced T2-weighted half-Fourier rapid acquisition with relaxation enhancement (RARE) magnetic resonance (MR) imaging with T1-weighted gadolinium-enhanced fast low-angle shot (FLASH) MR and standard examinations in the evaluation of Crohn disease. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Fifty-nine patients with ...

Fibrous dysplasia is a developmental disorder in which normal bone marrow is replaced by fibro-osseous tissue. The radiographic, CT and scintigraphic appearances of this condition are well known. The MRI appearances of fibrous dysplasia have not been widely published. The lesions are largely isointense with areas of hypointensity on T(1) ...

Animals with a portosystemic shunt (PSS) often have neurologic abnormalities. Diagnostic imaging, including brain magnetic resonance (MR) imaging, is not performed routinely in these animals. In this study, brain MR images were obtained in 13 dogs and three cats with a PSS, and in 15 dogs and five cats that ...

We present a rare case of pathologically proven inflammatory pseudotumor in the thoracic spine. The lesion showed an isointense signal on T1-weighted images, a heterogeneous iso- and hyperintense signal on T2-weighted images, and strong homogeneous enhancement. There was no evidence of abnormalities in the adjacent bone. Whereas the exact pathogenesis ...

BACKGROUND AND PURPOSE: The purpose of this study was to describe the CT and MR imaging findings of nodular fasciitis occurring in the head and neck region. METHODS: CT (n = 6) and MR (n = 4) images obtained from 7 patients (3 men and 4 women; mean age, 19.4 ...

A case of a pancreatic schwannoma is presented. The patient, a previously healthy woman, is hospitalized with the diagnosis of purulent pleuritis. Ultrasonography (US) of the abdomen shows a 3-cm mass in the head of the pancreas. Magnetic resonance imaging (MRI) reveals, in T1-weighted sequences, the mass to be hypointense, ...

Neurothekeomas are rare benign tumors of soft tissue that are of presumed neural sheath origin. This report describes the magnetic resonance imaging and computed tomography features of a neurothekeoma in the left forearm of a 38-year-old woman with a 2-year history of a painful mass. Magnetic resonance imaging showed a ...

OBJECTIVE: To describe the MRI features of extraskeletal myxoid chondrosarcoma in comparison with clinicopathologic findings. DESIGN AND PATIENTS: The study comprised 12 male subjects and seven female subjects with a mean age of 53 years (range 16-76 years). MRI findings, evaluated by two radiologists with agreement by consensus, were compared ...

We report the MR imaging findings in a 44-year-old man with a low-grade synovial sarcoma. There was a right-sided epidural and paravertebral mass, widening of the ipsilateral neural foramen at the L4-L5 level, and focal erosion of the right superior articular process of the L5 vertebra. The mass was relatively ...

Carcinoma showing thymus-like differentiation (CASTLE) is a rare tumor that occurs in the soft tissue of the neck or in the thyroid gland. We report a case of CASTLE in a 54-year-old man presenting with hoarseness. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a mass enclosing the right ...

Intraventricular hamartomas are extremely uncommon lesions outside of a setting of tuberous sclerosis. The second case of its kind in medical literature is presented and its possible aetiopathogenesis, imaging characteristics, pathognomonic magnetic resonance spectroscopy (MRS) and histopathology are discussed. An 11-year-old male presented with a seizure disorder for one year, ...

Curvilinear T1 hyperintense lesions in the cerebral cortex in patients with subacute infarction were investigated for: (1) the presence or absence of T2* hypointensity and (2) correlations with neuropathologic findings. Thirty-six consecutive patients with subacute to chronic embolic infarction, in whom curvilinear hyperintense lesions in the infarcted cortex were seen ...

OBJECTIVE: Solitary fibrous tumor (SFT) is a very rare tumor. The purpose of this study is to determine the MR imaging features of SFT in the intracranial and extracranial head and neck regions. MATERIALS AND METHODS: We retrospectively reviewed six MR images and two CT images of six histologically proven ...

PURPOSE: To prospectively determine the accuracy of differentiating benign focal nodular hyperplasia (FNH) from hepatic adenoma (HA) and liver adenomatosis (LA) by using gadobenate dimeglumine-enhanced magnetic resonance (MR) imaging. MATERIALS AND METHODS: The ethics committee at each center approved the study, and all patients provided informed consent. Seventy-three patients with ...

We retrospectively reviewed MR studies on 10 patients with renal-related perinephric fluid collections who underwent MRI in three institutions between January 2001 and August 2004. All patients underwent MRI of the abdomen and T1-weighted, T2-weighted and serial contrast-enhanced images, including delayed-phase contrast-enhanced images 10-12 min after contrast injection, were obtained. ...

A 70-year-old woman presented with fever and pain in the right lower extremity. Fat-suppressed gadolinium-enhanced T1-weighted magnetic resonance imaging (MRI) showed contrast-enhanced fascia, fluid accumulation, and hypointense signals in the muscles. Surgical interventions including incisions and insertion of drainage tubes were performed on the basis of the MRI findings. The ...

We report the magnetic resonance (MR) imaging findings of proliferative trichilemmal tumor (PTT), a rare benign tumor of the scalp. MR imaging showed a well-margined mass with isointense signal on T(1)-weighted images and heterogeneous mixed intensity signal on T(2)-weighted images After i.v. administration of contrast material, the mass showed significant ...

A 61-year-old female complained of low back pain, and had been treated by spinal anesthetic injection more than 70 times over 14 years. Magnetic resonance (MR) imaging, performed at the age of 47 years, revealed no abnormal lesion. However, she developed irritable hypesthetic pain in the left leg at 61 ...

The classification of certain vascular bone tumors that show an epithelioid cytologic appearance remains confusing, with overlap in features of epithelioid hemangioma, hemangioendothelioma and epithelioid hemangioendothelioma. Radiographs of a 27-year-old woman who presented with ankle pain showed an expanded lytic-sclerotic lesion in the distal left fibula. Magnetic resonance imaging showed ...

The aim of this study was to describe the MRI features of abdominal tuberculous lymphadenopathy. MRI studies of 13 patients with abdominal tuberculous lymphadenopathy were reviewed with regard to anatomic distribution and size. Signal intensities, in relation to abdominal wall muscle, on unenhanced T1- and T2-weighted images and patterns of ...

OBJECTIVE: To investigate the effect of iodinated contrast medium on sulcal hyperintensity on fluid-attenuated inversion recovery (FLAIR) imaging immediately after intra-arterial thrombolysis in patients with acute ischemic stroke and to determine whether it may be associated with subsequent hemorrhagic transformation (HT). METHODS: Fourteen consecutive patients with acute ischemic stroke who ...

OBJECTIVE: This study describes the findings of magnetic resonance imaging (MRI) of focal eosinophilic infiltration of the liver. METHODS: Contrast-enhanced MR images of 8 patients with focal hepatic eosinophilic infiltration were reviewed retrospectively. We evaluated the signal intensity of focal lesions in T1-weighted and T2-weighted images and the pattern of ...

OBJECTIVE: Idiopathic and diabetic-associated muscle necrosis are similar, uncommon clinical entities requiring conservative management and minimal intervention to avoid complications and prolonged hospitalization. An early noninvasive diagnosis is therefore essential. We evaluated the magnetic resonance imaging (MRI) characteristics of muscle necrosis in 14 patients, in eight of whom the diagnoses ...

An 8-year-old Beagle dog had exophthalmos of the left eye for the last two past months. On ophthalmoscopy, the intraocular lesion could not be evaluated due to the opacity of the cornea. Ultrasonography revealed that the eyeball was distorted in shape and shifted in position, however, the precise lesion could ...

Imaging findings in a 52-year-old woman with proven proliferative myositis are described. US revealed preservation of continuous muscle bundles and patchy areas of hyperechogenicity, containing hypoechoic lines. MRI showed at T2-w sequences an ill-defined, hyperintense, intramuscular lesion, containing isointense lines. Subtotal enhancement, a nonenhancing geometrical web, and fascial enhancement were ...

We report a case of cauda equina syndrome caused by Gnathostoma spinigerum, which was confirmed by an immunoblotting test. MR imaging of the lumbosacral spine showed long, segmented hyperintensity along the cauda equina with irregular enhancement on the postcontrast study. The conus medullaris was slightly enlarged with abnormal enhancement. The ...

To describe the signs that may be associated with intracranial inflammatory conditions, magnetic resonance (MR) images of 25 dogs that had inflammatory cerebrospinal fluid (CSF) were mixed with those of a control group of 40 dogs that had CSF negative for inflammatory disease and reviewed without knowledge of the clinical ...

PURPOSE: The purpose of this work was to determine the technical feasibility and value of dynamic subtraction (postcontrast-precontrast) magnetic resonance (MR) imaging for the assessment of hyperintense lesions on precontrast T1-weighted images in the cirrhotic liver. METHODS: One hundred four hyperintense lesions on T1-weighted precontrast and arterial phase postcontrast images ...

In 1998 some patients with hyperglycemia-related hemichorea-hemiballism have been reported with a hyperintense putamen on T1-weighted MR images, presumably resulting from petechial hemorrhage. I questioned this explanation from my experience because (1) the areas of hyperintense lesions and their time evolutions did not match with those of the high density ...

The aim of this study was to correlate MR findings of gallbladder wall thickening with pathologic findings on the basis of the layered pattern and to evaluate the diagnostic value of MR imaging in gallbladder disease. We retrospectively evaluated the source images of HASTE sequences for MR cholangiography in 144 ...

PURPOSE: To determine retrospectively whether addition of gadolinium-enhanced T1-weighted magnetic resonance (MR) sequence to T2-weighted turbo spin-echo (SE) MR imaging is valuable for preoperative assessment of T stage and circumferential resection margin in patients with primary rectal cancer. MATERIALS AND METHODS: Local institutional review board approved study and waived informed ...

BACKGROUND: We investigated the diagnostic importance of segmental high-intensity (SHI) areas not corresponding to mass lesions on T1-weighted magnetic resonance (MR) images. METHODS: We conducted a retrospective investigation of hepatic MR images obtained from 634 patients during a 4-year period at our institution. Images were compared with findings reported in ...

PURPOSE: To present CT and MR images and compare CT and MRI features of oral and maxillofacial hemangioma and vascular malformation. MATERIAL AND METHODS: The clinical materials consisted of nine vascular tumors from nine patients examined by both CT and MR scanners between November 1996 and March 2002. Both CT ...

The aim of this study was to investigate the role of magnetic resonance imaging (MRI) in the evaluation of response to radiofrequency ablation (RFA) and detect residual or recurrent tumor. After RFA, the target lesion shows a hyperintensive signal without increased T1-weighted, low on T2-weighted, non enhancing in gadolinium-enhanced MRI. ...

OBJECTIVE: To evaluate the magnetic resonance (MR) features of intramuscular myxoma (IM) compared with its pathological findings. DESIGN: Two radiologists retrospectively reviewed records and imaging studies of patients with histologically proven IM. Two radiologists also analyzed by consensus all the MR studies (pre- and post-contrast T1-weighted and T2-weighted sequences) and ...

BACKGROUND: Venous congestion of the brain stem due to dural arteriovenous fistulas (DAVFs) in the cavernous sinus is rare and presents therapeutic challenges. To assess the prognosis of patients with symptomatic DAVFs and brain stem dysfunction, we evaluated the degree of venous ischemia by examining pre- and post-treatment magnetic resonance ...

PURPOSE: To retrospectively evaluate the ultrasonographic (US), computed tomographic (CT), and magnetic resonance (MR) imaging features that differentiate traumatic neuroma from recurrent lymphadenopathy after neck dissection. MATERIALS AND METHODS: Imaging findings of 10 patients with a traumatic neuroma and 17 with recurrent lymphadenopathy were reviewed. US and CT were performed ...

PURPOSE: To evaluate ultrasound (US) and magnetic resonance (MR) findings in the viable twisted adnexa. MATERIALS AND METHODS: Ten patients underwent US and MR studies before surgical detorsion. Corrected cross-sectional area of the ovary was defined as cross-sectional area minus areas of cysts and follicles superior to 1 cm. On ...

AIM: To assess CT and MR manifestations and their diagnostic value in splenic hamartoma with review of literatures. METHODS: We described a woman who was accidentally found to have a splenic tumor by ultrasound of the abdomen. CT and MR findings of this splenic hamartoma were proved by pathology retrospectively. ...

OBJECTIVE: The purpose of our study was to evaluate whether MRI can discriminate between extraaxial neurofibromas and neurilemmomas. MATERIALS AND METHODS: MR images of 52 patients with a pathologically proven extraaxial neurofibroma or neurilemmoma were retrospectively reviewed by observers who were unaware of the surgical results, regarding the presence or ...