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: To evaluate the effect of Gd-DTPA on signal intensity of diffusion-weighted magnetic resonance (MR) image and apparent diffuse coefficient (ADC) in dog brain with hyperacute stroke. MATERIALS AND METHODS: Experimental canine model of hyperacute cerebral infarction was made by selective intraarterial embolization with particulate embolic material. Diffusion-weighted MR imaging was performed in five dogs at 1 hour after the embolization of internal carotid artery. After intravenous bolus injection of Gd-DTPA, additional 11 diffusion-weighted MR images were serially obtained from 2 minutes to 90 minutes after injection in each dog. The author evaluated findings of hyperacute cerebral infarction on diffusion-weighted MR imaging, and calculated mean signal intensity and mean ADC in infarcted region and contralateral normal region. Statistical analysis of mean signal intensity, mean ADC and contrast-noise ratio before and after Gd-DTPA injection was performed. RESULTS: Hyperacute cerebral infarction developed in all five dogs on diffusion-weighted MR images obtained 1 hour after embolization. The area of hyperacute infarction had steady increase in signal intensity on diffusion-weighted MR image and decrease in ADC. In normal perfusion area, decrease in signal intensity was observed at 2 minutes the Gd-DTPA injection, whereas ADC did not changed. CONCLUSION: Intravenous injection of Gd-DTPA had no influence on ADC in both hyperacute infarction and normally perfused area, but caused initial transient signal reduction in normally perfused area on diffusion-weighted MR image due to susceptibility effect of Gd-DTPA. It is important to calculate ADC in evaluating the effect of diffusion after injection of Gd-DTPA.
Animals ; Brain* ; Carotid Artery, Internal ; Cerebral Infarction ; Diffusion* ; Dogs ; Gadolinium DTPA* ; Infarction ; Injections, Intravenous ; Magnetic Resonance Imaging ; Perfusion ; Stroke*

Mucin-hypersecreting biliary neoplasm excretes excessive mucin that fills the biliary tree and results in marked dilatation of the bile ducts and obstructive jaundice. In these neoplasm, the mucin produced by the tumor rather than the tumor itself plays an important role in clinical course and radiologic patterns. The purpose of this paper is to report characteristic radiologic patterns of mucin-hypersecreting biliary neoplasms in two cases. These neoplasms were characterized by not only multilocular cystic hepatic mass or extra-hepatic bile duct mass resulting in marked biliary dilatation distal to the mass on US or CT, but also change of shape and extent of amorphous filling defects in the markedly dilated bile duct on serial cholangiograms.
Bile Ducts ; Biliary Tract ; Dilatation ; Jaundice, Obstructive ; Mucins

PURPOSE: To demonstrate a CT technique by which carcinoma of the ampulla of Vater can be more accurately diagnosed, and to describe the radiologic findings this carcinoma. MATERIALS AND METHODS: We retrospectively reviewed CT findings in 26 patients with pathologically proven carcinoma of the ampulla of Vater. One additional cup of diluted oral contrast medium was ingested immediately before the scan. We analysed the difference in detection rate of the mass in the duodenal lumen with and without duodenal luminal opacification of gastrografin.We also evaluated the size and shape of the mass, dilatation of CBD and the pancreatic duct, and lymph node metastasis. In addition, we analyzed multimodality imaging findings ultrasonogram (US) : 13; hypotonic duodenogram (HTDG): 7; ERCP : 17) of carcinoma of the ampulla of Vater. RESULTS: Nodular soft tissue masses protruding into the duodenal lumen were identified in 21 of 26 cases. In 95% of cases (21/22) with favorable opacification and distension of the duodenum, masses were clearly identified on CT imaging. However, in four caseswith poor opacification and distension of the duodenum, masses could not be observed(P=0.000). The mass on CT scanshowed a well-defined margin, round or lobulated contour, and contrast enhancement similar to that of thepancreas. CBD dilatation was identified in 20 cases and pancreatic duct dilatation in 12. On US, protruding massesin the distal CBD were observed in nine of 13 cases(60%) and on HTDG, in six of seven cases(86%). as well-definedfilling defects. Conclusion : Since the accuracy of CT diagnosis of intestinal lesions is directly proportional tothe degree of intestinal distension and opacification with oral contrast, we believe that adequate ct techniquefor distending and opacitying the duodeual lumen are necessary for early diagnosis of carcinoma of the ampulla ofVater.
Ampulla of Vater* ; Cholangiopancreatography, Endoscopic Retrograde ; Diagnosis ; Dilatation ; Duodenum ; Early Diagnosis ; Humans ; Lymph Nodes ; Neoplasm Metastasis ; Pancreatic Ducts ; Phenobarbital ; Retrospective Studies ; Ultrasonography

PURPOSE: To evaluate the ultrasonographic features of nonlactiferous breast abscess. MATERIALS AND METHODS: We retrospectively reviewed ultrasonograms of 21 cases with surgically and clinically proved nonlactiferous breast abscess. The cases included 17 cases of acute or chronic inflammation and 4 cases of tuberculosis. RESULTS: Location of the lesion was subareolar in 15 cases and peripheral in 6. Mean anteroposterior/transverse diameter ratio was 0.49. Internal echogenicitiy of the lesion was variable, with heterogeneous mixed-echoic echotexture in 18 cases and homogeneous hypoechoic in 3. Margin of the lesion was irregular in 18 cases(85.7%) and posterior sonic enhancement was observed in 17 cases(81%). There were also noted obliteration of adjacent superficial fascia, localized skin thickening, and sinus tract or ductal ectasia in 19(90.5%), 9 (42.9%), and 9(42.9%) cases respectively. CONCLUSION: Major ultrasonographic findings of nonlactiferous breast abscess was subareolar located, variable shaped mass with posterior enhancement. Additional findings were fistular formation, loss of superficial fascia, and axillary lymphadenopathy.
Abscess* ; Breast* ; Dilatation, Pathologic ; Inflammation ; Lymphatic Diseases ; Retrospective Studies ; Skin ; Subcutaneous Tissue ; Tuberculosis ; Ultrasonography

PURPOSE: To evaluate the ultrasonographic features of nonlactiferous breast abscess. MATERIALS AND METHODS: We retrospectively reviewed ultrasonograms of 21 cases with surgically and clinically proved nonlactiferous breast abscess. The cases included 17 cases of acute or chronic inflammation and 4 cases of tuberculosis. RESULTS: Location of the lesion was subareolar in 15 cases and peripheral in 6. Mean anteroposterior/transverse diameter ratio was 0.49. Internal echogenicitiy of the lesion was variable, with heterogeneous mixed-echoic echotexture in 18 cases and homogeneous hypoechoic in 3. Margin of the lesion was irregular in 18 cases(85.7%) and posterior sonic enhancement was observed in 17 cases(81%). There were also noted obliteration of adjacent superficial fascia, localized skin thickening, and sinus tract or ductal ectasia in 19(90.5%), 9 (42.9%), and 9(42.9%) cases respectively. CONCLUSION: Major ultrasonographic findings of nonlactiferous breast abscess was subareolar located, variable shaped mass with posterior enhancement. Additional findings were fistular formation, loss of superficial fascia, and axillary lymphadenopathy.
Abscess* ; Breast* ; Dilatation, Pathologic ; Inflammation ; Lymphatic Diseases ; Retrospective Studies ; Skin ; Subcutaneous Tissue ; Tuberculosis ; Ultrasonography

The IRB approval number should be corrected.

PURPOSE: In patients with colorectal cancer, preoperative staging using various imaging technologies is important for establishing the treatment plan and predicting the prognosis. Although computed tomography (CT) has been used most widely, the versatility of CT accuracy was primarily because of the lack of specialization. In this study, we aimed to identify whether any advancement in abdominal CT accuracy in the prediction of local staging has occurred. METHODS: Between December 2014 and November 2015, patients with colorectal cancer were retrospectively enrolled. All CT findings were retrospectively reported. A total of 285 patients were included, and their retrospectively collected data were retrospectively reviewed, focusing on a comparison between preoperative and postoperative staging. RESULTS: The overall prediction accuracy of the T stage was 55.1%, with overstaging occurring in 63 (22.1%) and understaging in 65 patients (22.8%). The sensitivity and specificity were 90.0% and 68.4%, respectively. The overall prediction accuracy of the N stage was 54.7%, with overstaging occurring in 89 (31.2%) and understaging in 40 patients (14.1%). The sensitivity and specificity were 71.9% and 63.2%, respectively. The CT accuracies by pathologic stage were 0%, 62.2%, 25.3%, and 81.2% for stages 0 (Tis N0), I, II, and III, respectively. CONCLUSION: CT has good sensitivity for detecting colon cancers with tumor invasion beyond the bowel wall. However, detection of nodal involvement using CT is unreliable. In our opinion, abdominal CT alone has limitations in predicting the local staging of colorectal cancer, and additional technologies, such as CT plus positron emission tomography and/or colonography, will improve its accuracy.
Colonic Neoplasms ; Colorectal Neoplasms* ; Humans ; Neoplasm Staging ; Positron-Emission Tomography ; Prognosis ; Retrospective Studies ; Sensitivity and Specificity ; Tomography, X-Ray Computed

The effects of r-aminobutyric acid(GABA) agonsits and antagonists were explored by the intracellular recording method to discern the preferential suppression of the ON component by GABA on the ON-OFF transient cell in the catfish (Ictalurus punctatus) retina. Experiments were performed in the superfused eyecup preparation. The animals were decapitated and pited before the eye, and the surrounding tissue was removed from the skull. The retina was exposed by excising the cornea, iris, and vitreous. This preparation rested on a wad of Ringer`s soaked cotton in contact with an Ag/Agcl reference electrode. Solutions were delivered through a manifold system that was connected to a pipette located near the absorbent wick. Electro-physiological recordings were made using standard intracellular electrodes filled with 2 M potassium acetate. The electrical signal was recorded with an amplifierand a penwriter, viewed on an oscilloscope, and stored on a data recorder. The light sources were red light-emitting-diode (LED) and the stimuli were full field illumination covering the cntire retina. GABA preferentially reduced ON light responses in ON-OFF transient cell. and GABA hyperpolarized bipolar cells, but the effects on ON bipolar cells were more sensitive than OFF bipolar cells. CACA and TACA, GABAc receptor agonist, did not act on bipolar cells. CACA and TACA, GABAc receptor agonists, hyperpolarized bipolar cells but the sensitivity deferences between ON and OFF bipolar cell were not observed. These results suggest that the preferential suppression of the ON component of the ON-OFF transient cell by GABA was resulted from the presynaptic mechanism that reduced bipolar cell input.
Animals ; Catfishes* ; Cornea ; Electrodes ; gamma-Aminobutyric Acid ; Iris ; Lighting ; Potassium Acetate ; Retina* ; Skull

For the investigation of the receptive field of the retinal neurons, the spatial and temporal properties of horizontal cells and the center-surround antagonisms of bipolar cells and the third-order neurons were studied using conventional intracellular recording techniques. Horizontal cells were hyperpolarized by the large annulus light stimuli (id: 3.5mm) and required at least 0.2 seconds of dark periods to respond enough. The amplitudes of the response of the ON-bipolar cell were decreased as the diameter of the spot stimuli was increased to 2.6mm and the responses were inverted at 2.6mm of inner diameter of the spreading annulus stimuli with fixed width. ON-sustained cell with spikes generated ON-sustained light responses by small annulus (1400-2100micrometer), but elicited OFF-sustained responses by large annulus (2100-2800micrometer). ON-sustained cell without spikes also showed surround antagonism. The spikes were generated at the spot of 490micrometer diameter and they were disappeared at the spot of 5600micrometer diameter. And, OFF-transient component of the ON-OFF transient cell was enhanced as annulus stimuli spread. The results suggest that the horizontal cells have large and monotonic receptive fields while the bipolar cells and the ON-sustained cells have large biphasic receptive fields in the catfish retina.
Catfishes* ; Neurons* ; Retina ; Retinal Neurons