Two patients with focal segmental glomerulosclerosis complicated by cyclosporine-induced reversible posterior leukoencephalopathy syndrome.

Reversible posterior leukoencephalopathy syndrome (RPLS) is a distinctive clinicoradiological entity observed in a variety of clinical settings. Cyclosporine (CyA)-RPLS has been reported in a few patients with focal segmental glomerulosclerosis (FSGS); however, there had been no reports on developed RPLS after the re-administration of CyA treatment. We report two patients with FSGS who developed CyA-induced RPLS and summarize the results of a literature review for similar patients. The two patients with FSGS presented here were a 4-year-old boy and a 9-year-old boy, who presented with steroid-resistant nephrotic syndrome (NS) and were treated with CyA. The first patient developed CyA-induced RPLS at the 7th day after the start of CyA treatment, and the second patient at the 16th day after the re-start of CyA treatment. The two patients complained of a visual disorder and exhibited signs of a disturbance in consciousness and hypertension. Electroencephalography (EEG) examinations revealed a generalized slow wave pattern, and magnetic resonance imaging (MRI) disclosed an area of high signal intensity in the white matter. Subsequently, CyA was discontinued and neurological symptoms improved and recrudescence of RPLS did not occur. Our findings suggest that patients with FSGS and NS who are treated with CyA should be closely monitored for the possible onset of RPLS, presenting as a disturbance in consciousness, visual disturbances and/or convulsions.

Strong green emission from alpha-SiAlON activated by divalent ytterbium under blue light irradiation.

This contribution reports on luminescence properties of divalent ytterbium in alpha-SiAlON at room temperature. Ytterbium-doped alpha-SiAlON powders, with the compositions of (M(1-2x/v)Yb(x))(m/v)Si(12-m-n)Al(m+n)O(n)N(16-n) (M = Ca, Li, Mg, and Y, v is the valency of M, 0.002 < or = x < or = 0.10, 0.5 < or = m = 2n < or = 3.5), were synthesized by sintering at 1700 degrees C for 2 h under 0.5 MPa N2. A single, intense, broad emission band, centered at 549 nm, is observed due to the electronic transitions from the excited state 4f(13)5d to the ground state 4f14 of Yb2+. The luminescence of Yb2+ in alpha-SiAlON occurs at relatively low energy, which is attributable to the large crystal field splitting and nephelauxetic effect due to the nitrogen-rich coordination of Yb2+. The dependence of luminescence properties on the Yb2+ concentration, chemical composition, and annealing is discussed. It is suggested that this novel green phosphor could be applied in white light-emitting diodes (LEDs) when combined with a red phosphor and a blue LED.

Visualization of pancreaticobiliary reflux in anomalous pancreaticobiliary junction by secretin-stimulated dynamic magnetic resonance cholangiopancreatography.

PURPOSE: To assess the utility of secretin-stimulated dynamic MR cholangiopancreatography (MRCP) for the visualization of pancreaticobiliary reflux in patients with anomalous pancreaticobiliary junction (PBJ). MATERIAL AND METHODS: Ten controls and seven patients diagnosed as having anomalous PBJ were prospectively examined by dynamic MRCP after secretin injection using a breath-hold, single-shot turbo spin-echo T2-weighted sequence. The optimal MRCP section was repeated 35 times at approx. 10-second interval after secretin injection; the acquisition time was 4 s per image. The signal intensity (SI) changes of the extrahepatic and intrahepatic bile ducts, presence or absence of intraluminal signal void, caliber change of the bile duct, duodenal filling, and peak time of the SI ratio of the extrahepatic bile duct after secretin injection were compared between the controls and patients. RESULTS: In the controls, the extrahepatic and intrahepatic bile ducts showed neither enhancement nor caliber change over the observation period, providing no apparent peak time. Of the seven patients, the extrahepatic bile duct showed retrograde enhancement and sequential delay in occurrence of the peak time from its distal third to its proximal third (n = 6) with a signal void in its distal part (n =4); its caliber increased subsequently to pancreatic secretion (n = 5); the intrahepatic bile ducts showed a slight enhancement following SI increase of the proximal extrahepatic bile duct (n = 6); duodenal filling grade tended to be lower in the patients than volunteers (P<.005). CONCLUSION: In patients with anomalous PBJ pancreaticobiliary reflux were demonstrated by dynamic secretin-stimulated MRCP.

Eclamptic encephalopathy: MRI, including diffusion-weighted images.

Eclampsia is a rare condition peculiar to pregnant and puerperal women. We analyse imaging features in five patients with eclampsia, and determine whether diffusion-weighted imaging (DWI) could differentiate cytotoxic and vasogenic oedema in four of them. All were imaged within 4 days of the onset of symptoms. We found lesions with a prolonged T2 in the brain of all five patients, in the basal ganglia in four, pons in three and posterior cerebral white matter in two. Isotropic DWI revealed variable intensity in these regions. The ADC was decreased in one, and increased in all the others. The lesion with reduced ADC progressed to infarction.

[Coronary sinus atrial septal defect diagnosed by cyanosis after operation of ventricular septal defect].

We have experienced a case of coronary sinus atrial septal defect (ASD) with ventricular septal defect (VSD). Cardiac catheterization revealed a step-up of oxygen saturation in right ventricle, L-R shunt 70.3%, R-L shunt 6.9% and pulmonary hypertension (PH). Since diagnosis of coronary sinus ASD was difficult, the operation was performed under diagnosis of VSD. Although the operation was success, cyanosis appeared after the operation. Contrast echocardiography using subcostal 4 chamber view showed coronary sinus ASD with a large Thebesian valve and the right-to-left shunt of the ASD. The Thebesian valve seemed to lead the venous return flow to the left atrium. Coronary sinus ASD was closed using a Xenomedica patch.

Magnetic resonance imaging and clinical findings examined in adulthood-studies on three adults with Rett syndrome.

PURPOSE: To clarify magnetic resonance imaging (MRI) findings in three adult patients with Rett syndrome who had been diagnosed with mental retardation and autism. METHOD: Clinical and MRI findings in three adult cases with Rett syndrome were studied. Ages (in years) in three adult cases with Rett Syndrome were 46 in Case 1, 35 in Case 2 and 20 in Case 3. They were able to walk and their convulsions were well controlled. RESULTS: MRI findings in all patients showed mild cerebral atrophy, especially in the frontal and temporal lobes and two of the cases also had mild cerebellar atrophy. One case also showed a narrowing of the brainstem and thinning of the corpus callosum. CONCLUSIONS: These results indicate that abnormalities in MRI imaging, in cases where there is narrowing of the brainstem and thinning of the corpus callosum, may be due to congenital hypoplasia. It was also seen that cerebellar atrophy became more distinct in older cases.

[Efficacy of continuous hepatic arterial infusion of high-dose 5-FU for liver metastases of gastric cancer].

We studied the efficacy of continuous hepatic arterial infusion of high-dose 5-FU (high-dose CHAI) in two patients with multiple (five or more) bilobar liver metastases of gastric cancer. 5-FU was given continuously via the hepatic artery at 1 g/day for 3 days, followed by one day off therapy and repetition of the initial treatment as one course. Case 1 was a 67-year-old man with Borrmann type 2 gastric cancer who had undergone total gastrectomy. Metachronous multiple liver metastases (maximum diameter: 3.5 cm) were detected at 11 months after surgery. One month later, we started high-dose CHAI and gave two courses with a 4-day interval between them. After that, 5-FU was given twice by hepatic arterial infusion (HAI) at dose of 1.5 g/week. The tumor diameter had decreased by 50% at 3 months after high-dose CHAI. Case 2 was a 64-year-old man with Borrmann type 3 gastric cancer who had synchronous multiple liver metastases (maximum diameter: 9 cm) and liver dysfunction. One month after distal gastrectomy, we started high-dose CHAI and finished one course. After that, liver function returned to normal and 5-FU was given by HAI at dose of 1 g/week on an outpatient basis. The tumor diameter decreased to 1/3 of the initial size at four months after high-dose CHAI. High-dose CHAI using 5-FU may be safe and effective for liver metastases from gastric cancer.

Power Doppler sonography of hepatocellular carcinoma treated by transcatheter arterial chemoembolization. Assessment of the therapeutic effect.

PURPOSE: To evaluate the usefulness of power Doppler sonography (PDS) in assessing the therapeutic effect of transcatheter arterial chemoembolization (TACE) in hepatocellular carcinoma (HCC). MATERIAL AND METHODS: TACE was performed in 43 patients (48 lesions) with HCC. All patients were examined with both PDS and color Doppler sonography (CDS) to assess the therapeutic results 1 week after TACE. Follow-up hepatic angiography was performed in 39 patients 3-4 months after TACE and then CT after iodized oil reinjection was also performed 3-4 weeks after a repeat TACE; in the remaining 4 patients, hepatectomy was performed within one month after chemoembolization and histologic study was undertaken to confirm the Doppler findings. RESULTS: Determination of therapeutic results with PDS and CDS were in agreement with those of follow-up findings in 37 and 29 of the 48 lesions, respectively. There was a significant difference in overall accuracy (p=0.038) between PDS and CDS results. CONCLUSION: PDS is more effective than CDS for evaluating changes in tumor vascularity after TACE. PDS may also replace angiography in assessing the therapeutic effects of TACE for HCCs, except in deep-seated areas.

[A case report: successful resection of advanced intrahepatic cholangiocarcinoma responding to preoperative hepatic artery infusion of 5-FU].

A patient with advanced intrahepatic cholangiocarcinoma had a tumor embolus in the right main branch of the portal vein and lymph node metastases. Hepatic arterial infusion (HAI) therapy with 5-FU (1 g/day) was given as a continuous infusion for 6 days. The treatment was repeated after a one-week interval. As a result the tumor diameter decreased by half, and the tumor embolus contracted. Cytoreductive surgery was then performed. The patient has been disease-free for over 9 months postoperatively with adjuvant HAI with 5-FU. We consider preoperative HAI with 5-FU (two courses of 1 g/day x 6 days) is both safe and effective.

Patterns of care study of radiation therapy for cervix cancer in Japan: the influence of the stratification of institution on the process.

BACKGROUND: To improve the quality of radiation oncology in Japan, Patterns of Care Study (PCS), a widely known quality assurance (QA) program in the USA, was introduced. The feasibility was tested by collecting nationwide data by extramural audit for cervix cancer. METHODS: From July 1996 through February 1997, PCS audits were performed for 29 institutions nationwide. On the basis of the facility survey by Tsunemoto, 13 institutions were classified as A1 (university hospital/cancer center), 10 as B1 (other institutions treating >120 patients/year) and six as B2 (other institutions treating <120 patients/year). Medical charts for the patients treated for cervix cancer between 1992 and 1994 were reviewed based on the data format of the US PCS. The total number of patients surveyed was 432. RESULTS: Simulation was used for >90% of the patients in both A1 and B1-2 institutions. However, in B1-2, planning for 5% of the patients was performed with only a clinical set-up (p = 0.0287). A daily fraction with a size of 200 cGy was given to >65% of patients in A1 and to <47% in B1-2. On the other hand, >50% of those in B1-2 were treated with daily fractions of 180 cGy and less compared with 25% in A1 institutions (p < 0.0001). Brachytherapy was utilized more frequently for patients in Stages II (p = 0.0365), III (p = 0.0015) and IV (p = 0.0483) in A1 than in B1-2. As for external beam equipment, linear accelerators with 10 MV or more were used for 83% of the patients in A1. However, in B1-2 institutions, machines with lower energy were used for 38% of the patients (p < 0.0001). The median number of full-time-equivalent (FTE) radiation oncologists was 2.7 in A1, 0.65 in B1 and 0.2 in B2. CONCLUSIONS: Institutional stratification, including equipment and personnel, was found to affect significantly the patterns of care for cervix cancer. Therefore, to improve the quality of radiation therapy nationwide, improvements in equipment and in supply of FTE personnel are extremely important. PCS was found to have great potential for a practical evaluation of how much improvement will be required in Japan.

Visualization of tumor vessels in hepatocellular carcinoma. Power Doppler compared with color Doppler and angiography.

PURPOSE: To assess the visualization of tumor vessels in hepatocellular carcinoma (HCC) by power Doppler sonography. MATERIAL AND METHODS: We examined 40 patients with 47 HCC lesions by means of power Doppler sonography and compared its visualization of tumor vessels with those of color Doppler and angiography. RESULTS: In 38 (81%) of the 47 lesions, power Doppler sonography improved the visualization of tumor vessels compared with color Doppler sonography; in the remaining lesions no significant difference was noted. In lesions located within 7 cm in depth, there was no significant difference between power Doppler sonography and angiography. In 10 (83%) out of 12 small (< or = 2 cm in diameter) lesions and in 11 (85%) out of 13 hypovascular lesions, power Doppler sonography performed considerably better than angiography. In deeper-seated lesions, however, angiography was significantly superior to power Doppler sonography. CONCLUSION: Power Doppler sonography is more sensitive in detecting the fine tumor vessels in most HCCs than color Doppler sonography. In addition, power Doppler sonography can replace angiography in evaluating tumor vascularity in HCCs except in lesions that are deep-seated or located near the heart. In these lesions, angiography can complement power Doppler sonography in demonstrating tumor vessels.

[Radiological diagnosis of viral encephalitis].

Most of viral encephalitis may demonstrate no specific change on CT and MR images. Brain swelling, edema, abnormal density (CT) and abnormal intensity (MR) can be detected in herpes simplex encephalitis and enterovirus encephalitis (coxsackie, echo, polio). The common finding on CT and MRI in patients with HIV encephalopathy are atrophy, leukomalacia. Progressive multifocal leukoencephalopathy (PML) shows multifocal oval or round white matter T2-hyperintensities on MR images. Subacute sclerosing panencephalitis (SSPE) may present slight changes in the subcortical and periventricular white matter, as well as basal ganglia. Progressive disorder makes widespread T1-low, T2-high intensity area and atrophy. MRI of acute disseminated encephalomyelitis (ADEM) shows multifocal subcortical hyper intense foci on T2-weighted studies. The deep white matter, brainstem, thalamus and cerebellum can be affected. Most of ADEM lesions resolve. Imaging findings of acute lymphocytic meningitis by echovirus and coxsackievirus are usually normal.

[MR angiography and MR cholangiopancreatography].

MR angiography is an adjunctive for noninvasive evaluation of blood vessels and MR cholangiopancreatography is for bile duct and pancreatic duct. Clinical applications of MR angiography has been focused mainly on head and neck and its applications to the abdomen are still limited. However, this technique has the good potential for the evaluation of portal vein system. MR cholangiopancreatography can depict bile ducts and pancreatic duct simultaneously and three-dimensionally. This technique can evaluate the causes of the lesion and its extent noninvasively. In this article the practical uses of MR angiography and MR cholangiography in the abdomen are discussed.

Acalculous cholecystitis (panniculitis) associated with Weber-Christian disease.

Acalculous cholecystitis occurred in a patient with Weber-Christian disease. It reflected a panniculitis similar to that which developed in the orbit, abdominal cavity, and the retroperitoneal space.

MRI of symptomatic sacral perineural cyst.

Sacral perineural cyst is a relatively rare condition. To our knowledge, reports of MR findings associated with sacral perineural cyst have been limited to only six cases. We present for the first time high field MR findings in a case of sacral perineural cyst. The cyst appeared as a cystic lesion in the sacral spinal canal and had intermediate signal intensity on T1W images and high signal intensity on T2*W images compared with CSF. Slight erosion remodeling of the sacrum was also seen anteriorly. Our case was symptomatic and present with radiculopathy (sciatic pain). Surgical treatment was done to result in dramatic improvement of the sciatic pain.

Asymmetric appearance of intracranial vessels on routine spin-echo MR images: a pulse sequence-dependent phenomenon.

PURPOSE: To determine the cause of right to left signal intensity differences arising from intracranial vessels during routine spin-echo axial MR imaging of the head. METHODS AND RESULTS: Using a normal imaging sequence in which the default directions of the frequency and phase axes were horizontal and vertical, respectively, differences in signal intensity arising from the vertebral arteries were observed in a healthy subject. With the exchange of the frequency and phase axes relative to the normal sequence, no signal intensity differences between the vertebral arteries were recognized. Other pulse sequence modifications, ie, the use of motion-compensating gradients and the reversed polarity of the frequency-encoding gradient, also resulted in variable appearances of the vertebral arteries, indicating that the right-to-left signal asymmetry of the vertebral arteries observed on the normal spin-echo image results from a pulse sequence dependent phenomenon. CONCLUSIONS: Frequency-encoding and slice-selection gradients both produce motion-induced phase shifts. These phase shifts depend on the angle between the direction of flow and that of the effective vector sum of these gradients. The asymmetric appearance of the vertebral arteries during normal spin-echo imaging was found to result from the angle dependence of motion-induced phase shifts. Awareness of this artifactual phenomenon is important to avoid confusing it with conditions such as stenosis/occlusion, dissection, or slow flow.

MR diagnosis of meniscal tears of the knee: value of axial three-dimensional Fourier transformation GRASS images.

Axial MR images of 40 knees in 37 patients with clinically suspected meniscal tears were obtained by using a three-dimensional (3-D) Fourier transform, gradient-refocused acquisition in the steady state (GRASS) pulse sequence. All knees also were examined in both coronal and sagittal planes with a two-dimensional (2-D) Fourier transform, spin-echo pulse sequence for T1-weighted images and a multiplanar GRASS pulse sequence for T2*-weighted images (conventional 2-D pulse sequences). Arthroscopic confirmation was available in all cases and was used as the gold standard. In these 40 knees, 32 of 33 meniscal tears and 45 of 47 normal menisci were correctly identified with axial 3-D imaging, yielding a sensitivity of 97% and specificity of 96%. Conversely, the sensitivity was 82% and the specificity was 100% for the 2-D technique in the diagnosis of meniscal tears. A combination of both techniques yielded 100% sensitivity, 100% specificity, and 100% accuracy in the evaluation of the menisci. Seven discrepancies between the findings of the two techniques were found in the evaluation of 33 arthroscopically proved torn menisci; six of the seven represented false-negative 2-D images and one was a false-negative axial 3-D image. Of 47 normal menisci, only two false-positives occurred with axial 3-D imaging and none with 2-D imaging. Despite the lack of a statistically significant difference, these preliminary findings suggest that the sensitivity in the diagnosis of meniscal tears can be improved by adding thin-sliced axial images with the 3-D GRASS pulse sequence to conventional 2-D imaging.

Pseudoenhancement of intervertebral disc herniation.

Two patients with intervertebral disc herniation appeared to demonstrate abnormally diffuse and intense enhancement of the disc after intravenous administration of gadolinium-DTPA for MRI. Surgery disclosed a dilated epidural venous plexus in one and vascular granulation tissue in the other, associated with the herniated disc material. The mechanism of this "pseudoenhancement" of the disc appears to be a partial volume effect of disc material and the adjacent veins or granulation tissue. Pseudoenhancement of a herniated disc should be included in the differential diagnosis of a diffusely enhancing epidural mass.

Follow-up MRI in dural arteriovenous malformations involving the cavernous sinus: emphasis on detection of venous thrombosis.

Six patients with a dural arteriovenous malformation (dural AVM) involving the cavernous sinus were followed up with magnetic resonance imaging in order to assess change in the lesions. Spin-echo (SE) imaging of three patients in whom the AVM appeared to have closed at least 1 month earlier (two of them spontaneously, and one after external carotid artery embolization) showed neither apparent flow void in the involved cavernous sinus nor evidence of venous thrombosis. SE images of the other three patients who had not been cured by external carotid artery embolization (two of whom were examined within a week of treatment), detected persisting arteriovenous shunts, including high-flow cortical venous drainage, seen as flow void. Two-dimensional time-of-flight MR angiography (2D TOF MRA) was performed simultaneously in three patients. Whereas shunting blood and the normal cavernous sinus were of high intensity, presumed thrombosed cavernous sinuses were isointense with stationary brain tissue. SE imaging can confirm the resolution of arteriovenous shunts, but poorly delineates very acute and chronic thrombosis of the draining veins. In contrast, 2D TOF MRA directly demonstrates flowing blood, permitting the diagnosis of venous thrombosis; it should be included in follow-up of a dural AVM involving the cavernous sinus when venous thrombosis is suspected.