Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease of probable autoimmune etiology. The MR images of patients with clinically suspected ADEM were retrospectively reviewed. The clinical symptoms occurred 5 days to 1 month after viral upper respiratory infection (4) and Coxsakie viral infection(1). The symptoms had begun with fever(3), headache(3), sore throat(1), and drowsy mental state (1), which progressed with monophasic course to altered mental change(2), extremity weakness(2), seizure(1) and/or cerebellary symptom(I) MRI findings of ADEM showed patchy(4), nonhemorrhagic(5), asymmetric(5) high signal intensity lesions on T2-weighted images. The number of the lesions was mostly multiple(4). The lesions mainly involved the brain stem(3) and subcortical white matter(3). Follow-up MR images of 13 days to 20 days after high dose steroid therapy showed marked improvement in two of three, which well correlated with clinical manifestations. MR findin of multiple, patchy, nonhemorrhagic and asymmetric lesions in subcortical white matter and brain stem on T2-weighted images seem to be characteristic features of ADEM, but nonspecific. Therefore, clinical correlation is required in evaluating ADEM.
Brain ; Brain Stem ; Demyelinating Diseases ; Encephalomyelitis, Acute Disseminated ; Extremities ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging* ; Retrospective Studies ; White Matter

PURPOSE: The purposes of this study were to analyze the MR findings of medulloblastoma, and to evaluate the subarachnoid dissemination and the significance of contrast enhanced MR of brain and spine for tumor.. MATERIALS AND METHODS: The preoperative brain MR studies of 18 patients (9 males, 9 females;mean age, 9.4 years) with surgically proved medulloblastomas were retrospectively reviewed to characterize these neoplasms with regard to their location, size, MR signal intensity, appearance after contrast enhancement, presence of cyst and necrosis, subarachnoid dissemination, and other associated findings. In 14 patients postoperative spine MR studies were evaluated for staging and therapeutic planning. RESULTS: The most frequent location of medulloblastoma was the inferior vermis and the mean tumor size was 4.1 x 3.6 x 3.9 cm. On Tl-weighted image, medulloblastomas generally had low to intermediate signal, predominantly hypointense relative to white matter. On T2-weighted image, medulloblastomas showed modetately high signal, hyperintense relative to white matter. Inhomogeneous contrast enhancement was demonstrated in 13 patients(72.2%) after injection of gadopentetate dimeglumine(Gadolinium). Cyst and necrosis within the tumor were visualized in 15 patients(83.3%). Subarachnoid disseminations of medulloblastomas were noted in 11 patients(61.1%), of which 6 demonstrated intracranial and 2 intraspinal dissemination. Three had both intracranial and intraspinal dissemination. In nine cases with intracranial lesions, there were intraparenchymal mass formation(7), subarachnoid nodules(5), infundibular lesions(2) and diffuse gyral enhancement(I). In five cases with intraspinal lesions, there were extramedullary intradural small nodules(3), central canal nodules(2), intradural masses(I)and fine nodular and sheet-like leptomeningeal enhancement(1). Other associated findings included intratumoral hemorrhage(11.1%), per/tumoral edema(44.4%), tonsillar herniation(44.4%), hydrocephalus(88.9%) and calcification(44.4%). CONCLUSION: Medulloblastomas revealed low to intermediate signal intensity on Tl-weighted image and intermediate to moderately high signal intensity on T2-weighted image, relative to cerebellar white matter. Medulloblastomas were solid tumors with cystic necrosis, which showed inhomogeneous enhancement and subarachnoid disseminations to the intracranial and intraspinal spaces after Gd-DTPA enhancement. Gd-enhanced MR of brain and spine was an useful diagnostic modality in preoperative diagnosis and in staging of postoperative cases of medulloblastomas, which was superior to postcontrast CT or precontrast MR.
Brain* ; Diagnosis ; Gadolinium DTPA ; Humans ; Male ; Medulloblastoma ; Necrosis ; Retrospective Studies ; Spine*

We report a case of cerebriform intradermal nevus. a cause of cutis verticis gyrata that clinically they resembled neurofibroma and revealed histopathologic finding consistent with intradermal nevus. The patient was a 6 year-old boy, who had a 17x18cm, soft, convoluted. pigmented mass over the parietal and occipital regions. The lesion had been present since birth and had been slowly increasing in size with convolution.
Child ; Humans ; Male ; Neurofibroma ; Nevus, Intradermal* ; Parturition ; Rabeprazole

PURPOSE: The purpose of this study is to describe Magnetic Resonance(MR) findings of two epidural cavernous malformations of the spine. MATERIALS AND METHODS: MR imaging was performed in 2 patients(29-year-old man and 54-year-old woman). Sagittal T1 -, T2-weighted images and Gadolinium (Gd)-enhanced axial and sagittal images were acquired. Two patients had surgery and MR findings were compared with surgical and histopathological findings. RESULTS: MR imaging showed high- and low-signal intensity components of these lesions that were characteristic of an epidural cavernous malformation in one case. The other case showed a high signal intensity on T2- and strong enhancement on Gd-enhanced T1 -weighted images. We think that the former may be due to mixed subacute and chronic hemorrhage and the latter may be due to blood within the endotheliumlined sinusolds without hemorrhage. CONCLUSION: These findings were well correlated with the surgical and histo-pathological findings of cavernous malformation.
Gadolinium ; Hemorrhage ; Humans ; Magnetic Resonance Imaging* ; Middle Aged ; Spine*

No abstract available.
Nasal Cavity* ; Papilloma, Inverted* ; Paranasal Sinuses*

The metal ceramic crown is currently the most popular complete veneer restoration in dentistry, but in many cases, the metal cervical collar at the facial margin is unesthetic and unacceptable. Facial porcelain margin has been used in place of it. But this dose not solve the problems, such as dark gingival discoloration and cervical opaque reflection of porcelain veneer. Recently, metal copings which were designed to terminate its labio-cervical end on the axial walls coronal to the shoulder have been clinically used to solve the esthetic problem of metal ceramic crown. But in this design, porcelain veneer of labio-cervical area which is not supported by metal may not be able to resist the stress during cementation and mastication. The purpose of this study was to evaluate fracture strength and fractured appearance of crowns according to different coping designs. A resin maxillary left central incisor analogue was prepared for a metal ceramic crown, and metal dies were made with duplication mold. Metal copings were made and assigned to one of four groups based on facial framework designs: group 1, coping with 0.5mm metal collar; group 2, metal extended to the shoulder; group 3, metal extended to 1 mm coronal to the shoulder; group 4, metal extended to 2mm coronal to the shoulder. Copings and crowns were adjusted to be same size and thickness, and cemented to metal dies with zinc phosphate cement by finger pressure. Fracture strength was measured with Instron Universal Testing Machine. Metaldies were anchored in Three-way-vice at 3mm below finish line and at 130degree inclined to the lone axis of the crown. Load was directed lingually at 2mm below midincisal edge. Load value at initial crack and at catastrophic fracture was recorded. The results obtained were as follows: 1. Fracture strength values at initial crack were higher in groups 1, 2 than in groups 3, 4 but this difference was not statistically significant(P<0.05). 2. Conventional metal collared crown had greater catastrophic fracture strength than any other collarless crowns. 3. The greater the labial metal coping reduction, the lower the catastrophic fracture strength of crowns but when more than 1mm of labial metal reduction was done, the difference in strengths was not statistically significant(p<0.05). 4. The strongest collarless coping design was group 2.
Axis, Cervical Vertebra ; Cementation ; Ceramics* ; Crowns* ; Dental Porcelain ; Dentistry ; Fingers ; Fungi ; Incisor ; Mastication ; Shoulder ; Zinc Phosphate Cement

OBJECTIVES: Hemodynamic measurements of chronic portal hypertension were done to study the mechanisms that maintain high portal pressure despite well developed collateral circulations. METHODS: A prehepatic portal hypertensive rat model was produced by partial portal vein ligation. Cardiac output, organ blood flow and porto-systemic shunt were measured by radioisotope labeled microsphere methods, and vascular resistance was calculated by standard equation. RESULTS: There was a significant reduction in the weight of the liver and increase in the weight of the spleen in the portal stenotic rats. Porto-systemic shunting, representing development of the collateral circulations, was 96.7+/-0.6% in the portal stenosis group compared with 0.9+/-0.2% in the control group (p<0.01). Portal pressure was significantly increased in the portal stenosis group compared with the control group(12.8+/-1.4 vs. 6.5+/-0.6mmHg; p<0.01). Mean arterial pressure was significantly decreased in portal stenosis group compared with control group(101.4+/-2.5 vs, 129.9+/-3.9mmHg; p<0.01). In the portal stenosis group, cardiac output(135.7+/-8.0 vs. 111.0+/-4.2ml/min; p<0.01) and splanchnic organ blood flow (28.97+/-2.03 vs. 17.90+/-1.27ml/min, p<0.01) were significantly increased, with concomitant decrease in total peripheral vascular resistance(58.0+/-3.3 vs. 88.2+/-4.8 dyne sec/cm5 X 105; p<0.01) and splanchnic vascular resistance(2.54+/-0.20 vs. 5.47+/-0.33 dyne sec/cm5 X 105; p<0.01), However, the portal venous resistance was not significantly different in both groups of rats (3.57+/-0.31 vs. 3.03+/-0.38 dyne sec/cm5 X 105; p>0.05). CONCLUSION: The hemodynamic results of this study indicate that hyperdynamic status of systemic and splanchnic circulation was present in chronic portal hypertension and that the primary factor contributing to the persistently elevated portal venous pressure was the markedly increased portal venous inflow.
Animals ; Arterial Pressure ; Cardiac Output ; Collateral Circulation ; Constriction, Pathologic ; Hemodynamics* ; Hypertension, Portal ; Ligation ; Liver ; Microspheres ; Models, Animal* ; Portal Pressure ; Portal Vein* ; Rats* ; Splanchnic Circulation ; Spleen ; Vascular Resistance

Cerebral aspergillosis is a rare condition that affects primarily the immunocompromised host. Most of cerebral aspergillosis is developed by hematogenous dissemination from extracranial foci, but aspergillosis of sino-nasal origin rarely affects the CNS. In case 1, wel symptom of tumor recurrence was unilateral numbness of the chin. A 65-year-old male was admitted because of paresthesia around the left chin and left lower lip. Neurologic examination revealed hypesthesia on the left side of chin, lower lip and buccal mucous mem-brane. Bone scan (Tc-99m MDP) showed focal hot uptakes on the left mandible and left first rib. Brain CT with bone window setting showed a focal osteolytic lesion in the bone marrow of the left mandibular canal without destruction of bone cortex. Both coronal T1 weighted image and axial T2 weighted image showed focal low signal intensities on the left ramus. The pathophysiologic mechanism could be understood by identification of the pathologic focus.
Aged ; Aspergillosis* ; Bone Marrow ; Brain ; Chin ; Humans ; Hypesthesia ; Immunocompromised Host ; Lip ; Male ; Mandible ; Neurologic Examination ; Paresthesia ; Recurrence ; Ribs

Dental restorative materials must have the physical properties to withstand wear and corrosion. Base metal alloys possess better mechanical properties and lower price than the gold alloys. For these reason such alloys have largely replaced the precious metal alloys. One aspect to consider is the release of metal substances to oral environment. The release of elements from dental alloys is a continuing concern because the elements may have the potentially harmful biological effects on local tissue. The purpose of this study was to minimize metal release on the nonprecious metal surfaces by ion bea assisted deposition(IBAD) of titanium nitride (TiN). Ni-Cr-Be alloys with and without TiN coatings were secured in an wear test machine opposing ruby ball to determine their relative resistance to wear with 100m, 200m, 300m and 400m sliding distance. And the corrosion behavior of the Ni-Cr-Be alloys with and without TiN coating and 3 dental noble alloys have been studied. Potentiodynamic curves were used to analyse the corrosion characteristics of the alloys. The measurement of the released Ni and Ci ions was conducted by analysis of the electrolyte solution with atomic absorption spectroscopy. The results were as follows : 1. The critical sliding distance that wore down TiN coating of 2.5micrometer thickness in this study condition was 300m. 2. Ion beam assisted deposition of TiN showed a good surface modification with respect to the properties of wear and corrosion resistance. 3. X-ray diffraction showed that the strongest peak of TiN(111) in the coatings. 4. The release of Ni and Cr ions from alloys measured by means of atomic absorption spectroscopy was reduced by ion beam assisted deposition of TiN.
Absorption ; Alloys* ; Corrosion ; Dental Alloys ; Gold Alloys ; Ions ; Spectrum Analysis ; Tin* ; Titanium ; X-Ray Diffraction

Intraspinal neurenteric cysts are rare congenital lesions that results from abnormal separation of germ layers in the third week of embryonic development, which may cause spinal compression. Although, the diagnosis of neurenteric cyst was very difficult prior to operation, MRI has proven to be a useful imaging modality in detection, localization and characterization of intraspinal neurenteric cysts. We recently experienced intraspinal neurenteric cyst in two patients who presented with progerssive quadriparesis. Myelography, CT myelography and MRI were taken and complete excision was performed. The MRI findings are presented and the literature is reviewed.
Diagnosis ; Embryonic Development ; Female ; Germ Layers ; Humans ; Magnetic Resonance Imaging* ; Myelography ; Neural Tube Defects* ; Pregnancy ; Quadriplegia