Decrease in leptomeningeal ivy sign on fluid-attenuated inversion recovery images after cerebral revascularization in patients with Moyamoya disease

BACKGROUND AND PURPOSE

The "ivy" sign that is identified on FLAIR images in patients with Moyamoya disease is considered to be leptomeningeal collaterals. The aim of our study was to evaluate the correlation between postoperative decrease in ivy sign and cerebral hemodynamic status in the bypass-established hemisphere.

MATERIALS AND METHODS

Twenty-two patients with Moyamoya disease were enrolled. Postoperative changes in the ivy sign on FLAIR images were examined in each patient after bypass surgery. The correlation between postoperative changes in the ivy sign and hemodynamic status was examined in 10 patients by using SPECT.

RESULTS

Of the 22 preoperative ivy-positive patients, 21 showed decreased ivy signs on the operative side. Average intervals between the operation day and the date when the decreased or vanished ivy sign was first recognized were 157.6 days in patients who underwent direct bypass and 212.2 days in patients who underwent indirect bypass. A postoperative decrease in ivy signs was found to be significantly correlated with an improved hemodynamic status of the surgically treated hemisphere, resulting in a postoperative increase in regional vascular reserve and a decreased proportion of the misery perfusion area (P < .01).

CONCLUSIONS

Postoperative changes in the ivy sign can be used as a marker for identifying improved hemodynamics and also for testing the effectiveness of cerebral revascularization.

Primary gastrointestinal stromal tumor of the liver with PDGFRA gene mutation

Gastrointestinal stromal tumor is a mesenchymal tumor with KIT or PDGFRA gene mutation, occurring primarily in the stomach and intestine and rarely outside the digestive tract. KIT-negative tumors with epithelioid cell morphology and PDGFRA mutation represent a minor subset of gastrointestinal stromal tumor. Here, we describe a case of gastrointestinal stromal tumor in the liver of a 70-year-old man. The tumor was shown to be completely limited within the liver by radiologic, intraoperative, and pathologic examinations. Histopathologically, the tumor showed epithelioid cell-type morphology and immunohistochemical expression of CD34 and protein kinase C theta but was negative for cytokeratin, EMA, S-100, and HMB-45. KIT protein expression was very faint, and we judged it as negative. Mutation analysis revealed the presence of PDGFRA gene mutation (V561D) at exon 12. These findings are essentially the same as those typically seen in ordinary KIT-negative epithelioid cell-type gastrointestinal stromal tumor of the digestive tract. Although KIT-negative gastrointestinal stromal tumor occurring outside the gastrointestinal tract is very rare, this entity should be considered as a potential primary hepatic neoplasm.

Unilateral hemispheric proliferation of ivy sign on fluid-attenuated inversion recovery images in moyamoya disease correlates highly with ipsilateral hemispheric decrease of cerebrovascular reserve

BACKGROUND AND PURPOSE

An ivy sign is considered to represent diffuse leptomeningeal collaterals found on fluid-attenuated inversion recovery (FLAIR) images of patients with Moyamoya disease. We evaluated the correlation between unilateral ivy proliferation in a hemisphere and cerebrovascular hemodynamic status to learn the clinical significance of the ivy sign.

MATERIALS AND METHODS

A total of 35 patients with Moyamoya disease were included. Correlation between ivy dominance on FLAIR images and hemodynamic status with use of iodine 123 N-isopropyl-p-iodoamphetamine ((123)I-IMP) single-photon emission CT (SPECT) was evaluated.

RESULTS

Distributional differences of ivy signs between both hemispheres were observed in 22 (64.7%) of 34 patients with a positive ivy sign, all of whom showed decreased vascular reserve/reactivity in the ivy-dominant hemisphere (IDH). The proportion of the stage II (misery perfusion) area to IDH was higher than that in the ivy less-dominant hemisphere (ILDH) in the quantitative analysis. The mean vascular reserve was lower in IDH than ILDH. There were 15 of 22 patients who had bypass surgery on IDH because of transient ischemic attack from ischemia of IDH. Patients with symmetric ivy distributions showed a variety of hemodynamic status. MR angiography (MRA) stage of IDH (2.95 +/- 0.39) was higher compared with ILDH (2.60 +/- 0.50; P < .05). Regional arteriocapillary circulation time ratio in IDH was longer compared with ILDH (P < .05). Ivy proliferation decreased in 10 (55.6%) of 18 patients who underwent bypass surgery during the follow-up period.

CONCLUSIONS

Unilateral hemispheric ivy proliferation correlated highly with the existence of an ipsilateral decreased vascular reserve associated with the development of leptomeningeal collaterals in patients with Moyamoya disease.

Visualization of the Superior Ophthalmic Veins by 3 Tesla 3D-TOF-MR Angiography

The superior ophthalmic veins (SOVs) are sometimes visualized on three-dimensional time-of-flight magnetic resonance (3D-TOF-MR) angiograms obtained with a 3 Tesla system. The purpose of this retrospective study was to determine the incidence of visualization of normal SOVs on 3D-TOF-MR angiograms, and their characteristic features. We reviewed 3D-TOF-MR angiograms of 345 consecutive patients obtained with a 3 Tesla MR device. Patients comprised 170 males and 175 females, aged five to 93 years. Most of the patients had, or were thought to have, cerebrovascular disease. The SOV was visualized in 13 of the 345 patients (3.8%). The visualized SOV was on the left side in seven of the 13, and on the right side in two. Both the right and left SOVs were visualized in four patients. The left SOV was more clearly visualized in two of these patients, whereas the SOVs were equally visible on both sides in the other two. There was a female predominance (M:F = 1:12) but no relation between age and visualization of SOVs. None of the visualized SOVs were dilated, and no dilated cavernous sinus was seen. The facial veins and angular veins were also visualized, continuing to the SOVs, suggesting rapid retrograde flow in the facial veins. SOVs are sometimes visualized on 3D-TOF-MR angiograms. This phenomenon should not be misdiagnosed as an asymptomatic dural carotid-cavernous fistula.

Poloidal mode analysis of magnetic probe data in a spherical tokamak configuration

A method to determine the poloidal mode number m in a spherical tokamak based on magnetic probe data was developed. Perturbed magnetic fields at Mirnov coils are calculated for distributed helical filamentary currents on rational surfaces assuming the maximum current amplitude, m and n (toroidal mode number), and the toroidal location of the filaments. These free parameters were determined from the best fit to the measured signals. The residual error was reduced by a factor of 2 by introducing helical filaments instead of toroidal filaments. Using this method, m/n=2/1 and 3/2 modes were identified in Mega-Ampere Spherical Tokamak discharges, and the time evolution of the tearing modes was derived.

The observation of nonlinear ion cyclotron wave excitation during high-harmonic fast wave heating in the large helical device

A wave detector, a newly designed magnetic probe, is installed in the large helical device (LHD). This wave detector is a 100-turn loop coil with electrostatic shield. Comparing a one-loop coil to this detector, this detector has roughly constant power coupling in the lower frequency range of 40 MHz, and it can easily detect magnetic wave in the frequency of a few megahertz. During high-harmonic fast wave heating, lower frequency waves (<10 MHz) were observed in the LHD for the first time, and for the power density threshold of lower frequency wave excitation (7.5 MHz) the power density of excited pumped wave (38.47 MHz) was approximately -46 dBmHz. These lower frequencies are kept constant for electron density and high energy particle distribution, and these lower frequency waves seem to be ion cyclotron waves caused by nonlinear wave-particle interaction, for example, parametric decay instability.

Detection of a new parametric decay instability branch in TST-2 during high harmonic fast wave heating

Parametric decay instability (PDI) is often observed in the TST-2 spherical tokamak during high harmonic fast wave heating by rf pickup probes. The frequency spectrum exhibits lower and upper sideband peaks in addition to the pump wave at f(0)=21 MHz. Two types of PDI are observed. One is the well-known decay into the ion-cyclotron quasimode (nf(ci)) and the ion Bernstein wave (f(0)-nf(ci)). The other is a newly found decay with the sideband frequency between f(0) and f(0)-f(ci). The frequency difference between this sideband and the pump increases in proportion to B(t). Moreover, high-speed visible light measuring systems with photomultiplier tubes or hybrid photodetectors viewing the plasma core detected oscillation of light emission at around f(0).

Pellet charge exchange helium measurement using neutral particle analyzer in large helical device

It is very important to investigate the confinement of alpha particles, which will be produced by nuclear reactions in ITER and fusion reactors. The pellet charge exchange (PCX) measurement is one of the most powerful methods because it can directly provide the profile of the alpha particle energy spectra in a plasma. In the large helical device, PCX using tracer encapsulated solid pellet (TESPEL) has been tried in many hydrogen and helium plasmas, including helium accelerated by using the cyclotron resonance heating. In the PCX, we use the compact neutral particle analyzer without simultaneous mass separation ability. The helium particle measurement can be achieved by the application of voltage in the condenser plate. The scattering of hydrogen particle is carefully considered during the estimation of the helium amount. The radial helium profiles can also be obtained by comparing four TESPEL injection shots with/without higher harmonic fast wave heating and at applied plate voltages for He or H, respectively.

Abnormal Flow in the Cavernous Sinus Caused by an Asymptomatic Dural Arteriovenous Fistula of the Contralateral Transverse-Sigmoid Sinus

A 53-year-old asymptomatic man underwent cranial MR imaging to rule out cerebrovascular disease. On T2-weighted axial images abnormal flow voids were detected at the right cavernous sinus, suggesting a dural carotid-cavernous fistula (CCF). On the MR angiogram, abnormal high intensity signals were observed at the right cavernous sinus and the left transverse-sigmoid (T-S) sinus, suggestive of coexisting right dural CCF and dural arteriovenous fistula (AVF) of the left T-S sinus. Selective cerebral angiography of the left external carotid artery revealed abnormal flow in the right cavernous sinus caused by the dural AVF of the left T-S sinus via the right inferior petrosal sinus due to occlusion of both the distal left sigmoid sinus and proximal right internal jugular vein.

Development of ion source with a washer gun for pulsed neutral beam injection

A new type of economical neutral beam source has been developed by using a single washer gun, pulsed operation, and a simple electrode system. We replaced the conventional hot filaments for arc-discharge-type plasma formation with a single stainless-steel washer gun, eliminating the entire dc power supply for the filaments and the cooling system for the electrodes. Our initial experiments revealed successful beam extraction up to 10 kV and 8.6 A, based on spatial profile measurements of density and temperature in the plasma source. The system also shows the potential to control the beam profile by controlling the plasma parameters in the ion accumulation chamber.

Direct measurement of density oscillation induced by a radio-frequency wave

An O-mode reflectometer at a frequency of 25.85 GHz was applied to plasmas heated by the high harmonic fast wave (21 MHz) in the TST-2 spherical tokamak. An oscillation in the phase of the reflected microwave in the rf range was observed directly for the first time. In TST-2, the rf (250 kW) induced density oscillation depends mainly on the poloidal rf electric field, which is estimated to be about 0.2 kV/m rms by the reflectometer measurement. Sideband peaks separated in frequency by ion cyclotron harmonics from 21 MHz, and peaks at ion cyclotron harmonics which are suggested to be quasimodes generated by parametric decay, were detected.

Manganese accumulation in the brain: MR imaging

Manganese (Mn) accumulation in the brain is detected as symmetrical high signal intensity in the globus pallidi on T1-weighted MR images without an abnormal signal on T2-weighted images. In this review, we present several cases of Mn accumulation in the brain due to acquired or congenital diseases of the abdomen including hepatic cirrhosis with a portosystemic shunt, congenital biliary atresia, primary biliary cirrhosis, congenital intrahepatic portosystemic shunt without liver dysfunction, Rendu-Osler-Weber syndrome with a diffuse intrahepatic portosystemic shunt, and patent ductus venosus. Other causes of Mn accumulation in the brain are Mn overload from total parenteral nutrition and welding-related Mn intoxication.

Middle cerebral artery occlusion causing intracerebral hemorrhage: radiologic findings

Middle cerebral artery (MCA) occlusion usually leads to cerebral infarction but rarely causes cerebral hemorrhage without infarction. We retrospectively investigated the unique radiographic manifestations in cases of cerebral hemorrhage without infarction. Computed tomography (CT) and angiographic images obtained in four patients (aged 26 to 70 years) with MCA occlusion associated with intracerebral hemorrhage were reviewed. Two patients also underwent magnetic resonance imaging (MRI), and one of these underwent magnetic resonance angiography as well; these images were also examined. Cranial CT revealed periventricular hemorrhage with ventricular penetration in one patient and with putaminal penetration in two. Solitary ventricular hemorrhage was found in the fourth patient. Angiography showed ipsilateral occlusion at the M1 portion of the MCA, accompanied by moyamoya-like vessels. No aneurysm or arteriovenous malformation was detected. MRI showed absence of the flow void in the affected MCA and an abnormal flow void in dilated collateral vessels in the basal ganglia. MCA occlusion can cause periventricular or ventricular hemorrhage, which appears to result from bleeding from fragile dilated collateral vessels and, thus, to have an etiology similar to that of adult moyamoya disease. MRI shows promise as a tool for evaluating the occlusion site.

Expression of sulfotransferase 1E1 in human prostate as studied by in situ hybridization and immunocytochemistry

BACKGROUND

Estrogen is recognized to play a role in the development and function of the prostate. Estrogen sulfotransferase (EST) 1E1 catalyzes the sulfoconjugation of estrogen and is thus involved in the metabolism of estrogen. We have recently shown that EST 1E1 is highly expressed in male mouse reproductive organs, including prostate. It appeared of interest to study the expression of EST 1E1 in human prostate.

METHODS

EST 1E1 mRNA and protein expression was evaluated in benign prostatic hyperplasia (BPH) using in situ hybridization and immunocytochemistry, respectively.

RESULTS

EST 1E1 mRNA and protein were found to be expressed in epithelial cells bordering alveola lumen (luminal cells) as well as stroma cells.

CONCLUSION

The enzyme EST may play a physiological role in regulating local estrogen levels in human prostate.

Endoglin (CD 105) is expressed on endothelial cells in the primary central nervous system lymphomas and correlates with survival

Endoglin (CD105) is predominantly expressed on the cellular lineages within the vascular system and it is overexpressed on proliferating endothelial cells that participate in neoangiogenesis, with a weak or negative expression in the vascular endothelium of normal tissues. To investigate the correlation between the CD105 expression and possible prognostic markers or progression in the primary central nervous system lymphomas (PCNSLs), the present study assessed 26 cases of PCNSL by immunostaining for CD105 and CD34. Intratumoral microvessel density (IMVD) was determined in the hotspots and interfaces at a magnification of x200. According to the mean value, the patients were classified into lower-IMVD and higher-IMVD groups. When CD34 was used as a marker of angiogenesis, the survival rates of these two groups demonstrated no significant difference. In contrast, when CD105 was used as a marker of angiogenesis, the survival rate of the lower-IMVD group was significantly higher than that for the higher-IMVD group (P < 0.01). In the group of CD34-immunostained vessels, no difference was observed in IMVD between the hotspots and interfaces (P = 0.31). In the group with CD105-immunostained vessels, a greater IMVD was observed in the hotspots than in the interfaces (P < 0.01). These results suggested that the growth of PCNSLs was dependent on angiogenesis, that IMVD as determined by anti-CD105 monoclonal antibody was a reliable prognostic marker in PCNSLs, and that PCNSLs may therefore not require sufficient neoangiogenesis at the start of PCNSLs, however, it may instead require a higher rate of neoangiogenesis as they infiltrate and destroy the brain parenchyma.

Percutaneous transhepatic obliteration for isolated gastric varices with gastropericardiac shunt: case report

Management of isolated gastric varices with a gastropericardiac shunt (GPS) has not yet been established. We were able to control a case of isolated gastric varices with a GPS by percutaneous transhepatic obliteration (PTO) using a microcatheter. In this case, the main blood drainage route was not a gastrorenal shunt, so transvenous retrograde obliteration could not be performed and PTO using the microcatheter was applied. Percutaneous transhepatic splenic venography revealed that the gastric varices came from the posterior gastric vein and the main drainage route was a GPS. Gastric varices and their blood supply were superselectively embolized using platinum microcoils and absolute ethanol. Portal venous pressure did not change after PTO because the route from the left gastric vein to the azygos venous system was preserved. Computed tomography 7 days after PTO revealed that the gastric varices were completely obliterated by the thrombi. Plasma ammonia level, arterial ketone body ratio, and indocyanine green retention rate at 15 min were improved. We conclude that PTO using a microcatheter is a rational, effective, and safe therapy for isolated gastric varices with a GPS.

Role of percutaneous transhepatic obliteration for special types of varices with portal hypertension

The treatment of special types of varices with portal hypertension has not yet been established. We were able to control 13 cases of special types of varices by percutaneous transhepatic obliteration (PTO). These 13 cases consisted of 2 esophagojejunal varices after total gastrectomy for gastric cancer, 1 stoma varices after abdominoperineal excision for rectal cancer, 2 mesenteric varices with encephalopathy, 1 gastric variceal rupture, 1 gastrorenal and gastroazygos shunt with encephalopathy, 3 giant bar-type esophageal varices, 2 isolated gastric varices with gastropericardiac shunts, and 1 isolated gastric varices with gastrophrenic shunt. The special types of varices were successfully embolized in all cases and there were no complications. We conclude that the PTO is still an effective and safe treatment for special types of varices with portal hypertension.