AB0470 THE ASSOCIATIONS OF ANTI-DNA ANTIBODIES WITH DISEASE ACTIVITY INDICES AND PATIENT REPORT OUTCOME PARAMETERS OF SLE IN KYOTO LUPUS COHORT

Background

Since the goals of remission or low disease activity are becoming more realistic with advances in treatment for SLE, there is a need to examine the measurements for SLE especially in patients with low disease activity. It has been known that disease activities in SLE are correlated with anti-DNA antibodies (Abs). However, it was not clear which measurements of disease activities or patient reported outcomes correlate better with anti-DNA Abs.

Objectives

To examine the association between parameters for SLE and anti-DNA Abs measured with RIA in Kyoto Lupus Cohort, a SLE registry in Kyoto University Hospital from 2019 to 2021.

Methods

1)Correlations between anti-DNA Abs with SLEDAI, M-SLEDAI (SLEDAI without anti-DNA Abs), VAS, LupusPRO, SF-36, and Systemic lupus erythematosus Symptom Checklist (SSC) were evaluated cross-sectionally (n = 310).

2)The alterations in SLE parameters and anti-DNA Abs between two visits were examined (n = 106). Further, the correlations within 3 months were examined in cases with flare-ups of SLE (the alteration in SLEDAI > 0 and anti-DNA Abs≧0, n = 39). The associations of the alterations of anti-DNA Abs with each item of SLEDAI classified by organs were also examined.

Results

1)31 percent of the cases in the entire registry was classified as remission or low disease activity (Table 1). SLEDAI (mean±SD) was higher in patients positive for anti-DNA Abs (7.94±5.20) than that in patients negative for anti-DNA Abs (4.56±4.65) (p < 0.0001). Anti-DNA Abs were weakly correlated with SLEDAI (R = 0.24 [p < 0.0001]), M-SLEDAI (R = 0.15 [p = 0.014]), and Physician-VAS (R = 0.19 [p = 0.0016]). On the other hand, there were no significant correlations between anti-DNA Abs and LupusPRO and SSC. Some dimensions in SF-36 had weak correlations with anti-DNA Abs, while no component summary scores had significant correlations with anti-DNA Abs.

Table 1.

Patients’ demographics and disease characteristics in the cohort (n = 310).

VariableResultsAge (years)47.7 (39.4, 57.5)Female sexn = 284 (91.6%)Disease duration (years)15.9 (9.4, 24.5)Anti-DNA Ab positivity†n = 106 (34.2%)Anti- DNA Ab titer (U/mL)4 (0, 8)SLEDAI4 (2, 8)SLEDAI<=4n = 162 (52.1%)SSC31 (16.2, 52.5)Remission or LDAn = 95 (30.7%)Patient-VAS38 (15, 52)Physician-VAS13.3 (3.3, 23.3)SF-36 PCS45.4 (36.6, 52.4)SF-36 MCS48.2 (41.5, 53.6)SF-36 RCS51.3 (42.6, 58.6)LupusPRO HQOL70.2 (54.8, 86.5)LupusPRO NHQOL41.7 (31.3, 51.0)Glucocorticoid (mg/day)5 (4, 8)

* Data are n (%) or median (Q1, Q3).

† Anti-DNA Ab positivity at the time of the cross-sectional observation.

2)No significant correlations were observed between the alterations of SLEDAI and anti-DNA Abs (R = 0.00 [95% CI: -0.23 – 0.22, p = 0.95]) in the total of patients with various range of observation periods (Figure 1A). In contrast, a significant correlation was observed (R = 0.32, p = 0.04) within 3 months after the flare-ups of SLE (Figure 1B). No significant correlations were found between the alterations in VAS and anti-DNA Abs, or the alterations of SSC and anti-DNA Abs. They showed the following organ symptoms: renal involvement, 62.8%; musculoskeletal, 17.1%; neuropsychiatric, 11.4%; hematological, 5.7%; mucocutaneous, 11.4%; serositis, 2.9%, and fever, 2.9%.

Figure 1.

The associations between the alteration in anti-DNA Ab and SLEDAI

Conclusion

The associations between anti-DNA Abs with several parameters of SLE were examined. Anti-DNA Abs correlated with disease activities (SLEDAI) in SLE patients, especially when observed in the condition of flare-up.

References

[1]Ho A, et al. Arthritis Rheum. 2001;44:2342-9.

Disclosure of Interests

None declared

Multi-energy reconstructions, central electron temperature measurements, and early detection of the birth and growth of runaway electrons using a versatile soft x-ray pinhole camera at MST

A multi-energy soft x-ray pinhole camera has been designed, built, and deployed at the Madison Symmetric Torus to aid the study of particle and thermal transport, as well as MHD stability physics. This novel imaging diagnostic technique employs a pixelated x-ray detector in which the lower energy threshold for photon detection can be adjusted independently on each pixel. The detector of choice is a PILATUS3 100 K with a 450 μm thick silicon sensor and nearly 100 000 pixels sensitive to photon energies between 1.6 and 30 keV. An ensemble of cubic spline smoothing functions has been applied to the line-integrated data for each time-frame and energy-range, obtaining a reduced standard-deviation when compared to that dominated by photon-noise. The multi-energy local emissivity profiles are obtained from a 1D matrix-based Abel-inversion procedure. Central values of T_e can be obtained by modeling the slope of the continuum radiation from ratios of the inverted radial emissivity profiles over multiple energy ranges with no a priori assumptions of plasma profiles, magnetic field reconstruction constraints, high-density limitations, or need of shot-to-shot reproducibility. In tokamak plasmas, a novel application has recently been tested for early detection, 1D imaging, and study of the birth, exponential growth, and saturation of runaway electrons at energies comparable to 100 × T_e,0; thus, early results are also presented.

THU0285 ANALYSIS OF THE RELATIONSHIP BETWEEN ORGAN DAMAGE AND QUALITY OF LIFE IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

Systemic lupus erythematosus (SLE) is an autoimmune disease that can not only cause systemic symptoms, such as fever and arthritis, but can also damage important organs, such as those of the central nervous system and the kidneys. Prevention of irreversible organ damage is important for better prognosis [1]. Additionally, the importance of maintaining the quality of life (QOL) of patients has recently been emphasized. However, only a few studies have examined the relationship between irreversible organ damage and patient QOL.

Objectives:

To assess the relationship between organ damage and QOL, and to survey which organs have more significant effects on QOL.

Methods:

We conducted a questionnaire-based survey of 183 patients with SLE at Kyoto University Hospital from September to December 2019. We used the SLICC/ACR Damage Index (SDI) to evaluate organ damage [2]. The following five scales were employed to evaluate QOL: the physical (PCS) and mental component summary (MCS) of the Medical Outcome Study (MOS) 36-Item Short-Form Health Survey version 2.0 (SF-36v2) [3], health (HRQOL) and non-health-related QOL (N-HRQOL) of LupusPRO [4], and SLE Symptom Checklist (SSC) [5].

Results:

Linear regression analysis showed significant correlation between the SDI score and all QOL scales except for N-HRQOL, suggesting negative effects of organ damage on QOL (Table 1). Next, we analysed whether there was a significant difference in the SF-36 score between those who were positive and negative for each SDI item (41 in total), using the Wilcoxon rank sum test. Muscle atrophy or weakness (p= 3.0×10-10), osteoporosis with fracture or vertebral collapse (p= 9.7×10-8), claudication (p= 7.4×10-5), and cognitive impairment or major psychosis (p= 9.9×10-5) significantly correlated (p< 1.2×10-3) with PCS, and scarring chronic alopecia (p= 3.4×10-4) with MCS (Table 2). In addition, the five SDI items significantly correlated with the remaining three QOL scales (HRQOL, N-HRQOL, and SSC;p< 0.05).

Table 1.

Relationship between the SDI score and QOL

SF-36LupusPROSSCPCSMCSHRQOLN-HRQOLp-value<2.0×10-161.7×10-32.2×10-110.231.9×10-8Table 2.

Relationship between each SDI item and the SF-36 score (p< 1.2×10-3

SDI itemPCS scorep-valuePositive(Median (IQR))Negative(Median (IQR))Muscle atrophy/weakness33 (19-45)50 (43-54)3.0×10-10Osteoporosis with fracture/vertebral collapse24 (12-32)49 (38-54)9.7×10-8Claudication31 (19-35)49 (38-54)7.4×10-5Cognitive impairment/psychosis27 (17-33)49 (38-54)9.9×10-5SDI itemMCS scorep-valuePositive(Median (IQR))Negative(Median (IQR))Scarring chronic alopecia42 (29-51)49 (39-54)3.4×10-4

Conclusion:

We demonstrated that organ damage has negative effects on patient QOL, indicating the importance of preventing irreversible organ damage for maintaining QOL. Moreover, muscle atrophy/weakness, osteoporosis with fracture/vertebral collapse, claudication, cognitive impairment/major psychosis, and scarring chronic alopecia significantly correlated with QOL deterioration, suggesting that these items should be examined with special care in clinical practice.

References:

[1]Lopez R, et al. Rheumatology (Oxford). 2012; 51:491-498.

[2]Gladman D, et al. Arthritis Rheum. 1996; 39:363-369.

[3]Fukuhara S, et al. J Clin Epidemiol. 1998; 51:1037-1044.

[4]Inoue M, et al. Lupus. 2017; 26:849-856.

[5]Grootscholten C, et al. Qual Life Res. 2003; 12:635–644.

Disclosure of Interests:

Yudai Takase: None declared, Hiroshi Doi: None declared, Takeshi Iwasaki: None declared, Motomu Hashimoto Grant/research support from: Bristol-Myers Squibb, Eisai, and Eli Lilly and Company., Speakers bureau: Bristol-Myers Squibb and Mitsubishi Tanabe Pharma., Ryuta Inaba: None declared, Tomohiro Kozuki: None declared, Masashi Taniguchi: None declared, Yuya Tabuchi Paid instructor for: Astellas Pharma, GlaxoSmithKline, Mitsubishi Tanabe Pharma, and Nippon Shinyaku., Speakers bureau: AbbVie, Janssen Pharmaceutical, Mitsubishi Tanabe Pharma, Nippon Shinyaku, and Novartis Pharma. (Outside the field of the present study.), Koji Kitagori: None declared, Syuji Akizuki: None declared, Kosaku Murakami Speakers bureau: AbbVie, Eisai, and Mitsubishi Tanabe Pharma., Ran Nakashima Grant/research support from: Takeda Pharmaceutical. (Outside the field of the present study.), Speakers bureau: Astellas Pharma, Medical & Biological Laboratories, AstraZeneca, and Boehringer Ingelheim. (Outside the field of the present study.), Hajime Yoshifuji Grant/research support from: Astellas Pharma. (Outside the field of the present study.), Speakers bureau: Chugai Pharmaceutical. (Outside the field of the present study.), Wataru Yamamoto: None declared, Masao Tanaka Grant/research support from: AbbVie, Asahi Kasei Pharma, Astellas Pharma, Ayumi Pharmaceutical, Chugai Pharmaceutical, Eisai, Mitsubishi Tanabe Pharma, Taisho Pharmaceutical, and UCB Japan.

, Speakers bureau: AbbVie, Asahi Kasei Pharma, Astellas Pharma, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Eli Lilly and Company, Janssen Pharmaceutical, Mitsubishi Tanabe Pharma, Novartis Pharma, Pfizer, Taisho Pharmaceutical, Takeda Pharmaceutical, and UCB Japan., Koichiro Ohmura Grant/research support from: Astellas Pharma, AYUMI Pharmaceutical, Chugai Pharmaceutical, Daiichi Sankyo, Eisai, Japan Blood Products Organization, Mitsubishi Tanabe Pharma, Nippon Kayaku, Nippon Shinyaku, Sanofi, and Takeda Pharmaceutical., Speakers bureau: AbbVie, Actelion Pharmaceuticals Japan, Asahi Kasei Pharma, AYUMI Pharmaceutical, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Eli Lilly and Company, GlaxoSmithKline, Janssen Pharmaceutical, Mitsubishi Tanabe Pharma, Novartis Pharma, and Sanofi.

A computational tool for simulation and design of tangential multi-energy soft x-ray pin-hole cameras for tokamak plasmas

A new tool has been developed to calculate the spectral, spatial, and temporal responses of multi-energy soft x-ray (ME-SXR) pinhole cameras for arbitrary plasma densities (n _e,D), temperature (T _e), and impurity densities (n _Z). ME-SXR imaging provides a unique opportunity for obtaining important plasma properties (e.g., T _e, n _Z, and Z _eff) by measuring both continuum and line emission in multiple energy ranges. This technique employs a pixelated x-ray detector in which the lower energy threshold for photon detection can be adjusted independently. Simulations assuming a tangential geometry and DIII-D-like plasmas (e.g., n _e,0 ≈ 8 × 10¹⁹ m^-3 and T _e,0 ≈ 2.8 keV) for various impurity (e.g., C, O, Ar, Ni, and Mo) density profiles have been performed. The computed brightnesses range from few 10² counts pixel^-1 ms^-1 depending on the cut-off energy thresholds, while the maximum allowable count rate is 10⁴ counts pixel^-1 ms^-1. The typical spatial resolution in the mid-plane is ≈0.5 cm with a photon-energy resolution of 500 eV at a 500 Hz frame rate.

Simulation, design, and first test of a multi-energy soft x-ray (SXR) pinhole camera in the Madison Symmetric Torus (MST)

A multi-energy soft x-ray pinhole camera has been designed and built for the Madison Symmetric Torus reversed field pinch to aid the study of particle and thermal-transport, as well as MHD stability physics. This novel imaging diagnostic technique combines the best features from both pulse-height-analysis and multi-foil methods employing a PILATUS3 x-ray detector in which the lower energy threshold for photon detection can be adjusted independently on each pixel. Further improvements implemented on the new cooled systems allow a maximum count rate of 10 MHz per pixel and sensitivity to the strong Al and Ar emission between 1.5 and 4 keV. The local x-ray emissivity will be measured in multiple energy ranges simultaneously, from which it is possible to infer 1D and 2D simultaneous profile measurements of core electron temperature and impurity density profiles with no a priori assumptions of plasma profiles, magnetic field reconstruction constraints, high-density limitations, or need of shot-to-shot reproducibility. The expected time and space resolutions will be 2 ms and <1 cm, respectively.

SurePath® LBC improves the diagnostic accuracy of intrahepatic and hilar cholangiocarcinoma

INTRODUCTION

The current study aimed to compare cytology using SurePath^® (SP)-LBC and biliary tissue histology (BTH) for the diagnosis of biliary disease.

METHODS

Between January 2014 and December 2016, 57 patients underwent endoscopic retrograde cholangiopancreatography for the diagnosis of biliary disease. Biliary cytological samples were processed using SP-LBC and subsequently BTH was performed. A final diagnosis was confirmed by surgery (23 malignant cases) and clinical follow-up (34 benign and malignant cases): 18 extrahepatic cholangiocarcinoma; 17 intrahepatic/hilar cholangiocarcinoma (intra/H-CC); eight other malignant disease; and 14 benign biliary disease. The diagnoses made using SP-LBC and BTH were classified into four categories: (1) benign; (2) indeterminate; (3) suspicious for malignancy/malignant; and (4) inadequate. In addition, diagnostic accuracy was compared between SP-LBC and BTH.

RESULTS

Although 23% (13/57) of BTH samples were classified as inadequate, all SP-LBC cases were classified as adequate. Among 43 malignant cases, 11 normal, four indeterminate and 28 suspicious for malignancy/malignant were found using SP-LBC (26%, 9% and 65%, respectively), in contrast to 10 inadequate, nine normal, 10 indeterminate and 14 suspicious for malignancy/malignant observed using BTH (23%, 21%, 23%, and 33%, respectively). The identification of malignant cells was strikingly different between SP-LBC and BTH. Furthermore, limited to intra/H-CC, accuracy was significantly higher using SP-LBC than using BTH (P < .001).

CONCLUSIONS

SP-LBC of the biliary tract is a useful and reliable method for diagnosing biliary malignant disease and has an advantage over BTH for detecting malignant cells and accurately diagnosing intra/H-CC.

A Combined test using both cell sediment and supernatant cell-free DNA in pleural effusion shows increased sensitivity in detecting activating EGFR mutation in lung cancer patients

INTRODUCTION

The aim of this study was to examine whether a combined test using both cell sediment and supernatant cytology cell-free DNA (ccfDNA) is more useful in detecting EGFR mutation than using cell sediment DNA or supernatant ccfDNA alone in pleural effusion of lung cancer patients.

METHODS

A total of 74 lung adenocarcinoma patients with paired samples between primary tumour and corresponding metastatic tumour with both cell sediment and supernatant ccfDNA of pleural effusion cytology were enrolled in this study. Cell sediment and supernatant ccfDNA were analysed separately for EGFR mutations by polymerase chain reaction.

RESULTS

Out of 45 patients with mutant EGFR in primary tumours, EGFR mutations were detected in 23 cell sediments of corresponding metastases (sensitivity; 51.1%) and 20 supernatant ccfDNA corresponding metastases (sensitivity; 44.4%). By contrast, the combined test detected EGFR mutations in 27 corresponding metastases (sensitivity; 60.0%), and had a higher sensitivity than the cell sediment or the supernatant ccfDNA alone (P < .05). Out of 45 patients with mutant EGFR, 24, three and 18 were cytologically diagnosed as positive, atypical or negative, respectively. The detection rate in the combined test was highest (95.8%) in the positive group, and mutant EGFR was also detected in four of 18 samples (22.2%) in the negative group.

CONCLUSIONS

A combined test using both cell sediment DNA and supernatant ccfDNA samples increases the concordance rate of EGFR mutations between primary tumour and corresponding metastases. Our findings indicate that supernatant ccfDNA is useful even in cases where the cytological diagnosis is negative.

Measurement of thickness of film deposited on the plasma-facing wall in the QUEST tokamak by colorimetry

After several experimental campaigns in the Kyushu University Experiment with Steady-state Spherical Tokamak (QUEST), the originally stainless steel plasma-facing wall (PFW) becomes completely covered with a deposited film composed of mixture materials, such as iron, chromium, carbon, and tungsten. In this work, an innovative colorimetry-based method was developed to measure the thickness of the deposited film on the actual QUEST wall. Because the optical constants of the deposited film on the PFW were position-dependent and the extinction coefficient k₁ was about 1.0-2.0, which made the probing light not penetrate through some thick deposited films, the colorimetry method developed can only provide a rough value range of thickness of the metal-containing film deposited on the actual PFW in QUEST. However, the use of colorimetry is of great benefit to large-area inspections and to radioactive materials in future fusion devices that will be strictly prohibited from being taken out of the limited area.

Validations of calibration-free measurements of electron temperature using double-pass Thomson scattering diagnostics from theoretical and experimental aspects

This paper evaluates the accuracy of electron temperature measurements and relative transmissivities of double-pass Thomson scattering diagnostics. The electron temperature (T_e) is obtained from the ratio of signals from a double-pass scattering system, then relative transmissivities are calculated from the measured T_e and intensity of the signals. How accurate the values are depends on the electron temperature (T_e) and scattering angle (θ), and therefore the accuracy of the values was evaluated experimentally using the Large Helical Device (LHD) and the Tokyo spherical tokamak-2 (TST-2). Analyzing the data from the TST-2 indicates that a high T_e and a large scattering angle (θ) yield accurate values. Indeed, the errors for scattering angle θ = 135° are approximately half of those for θ = 115°. The method of determining the T_e in a wide T_e range spanning over two orders of magnitude (0.01-1.5 keV) was validated using the experimental results of the LHD and TST-2. A simple method to provide relative transmissivities, which include inputs from collection optics, vacuum window, optical fibers, and polychromators, is also presented. The relative errors were less than approximately 10%. Numerical simulations also indicate that the T_e measurements are valid under harsh radiation conditions. This method to obtain T_e can be considered for the design of Thomson scattering systems where there is high-performance plasma that generates harsh radiation environments.

A model of plasma current through a hole of Rogowski probe including sheath effects

In TST-2 Ohmic discharges, local current is measured using a Rogowski probe by changing the angle between the local magnetic field and the direction of the hole of the Rogowski probe. The angular dependence shows a peak when the direction of the hole is almost parallel to the local magnetic field. The obtained width of the peak was broader than that of the theoretical curve expected from the probe geometry. In order to explain this disagreement, we consider the effect of sheath in the vicinity of the Rogowski probe. A sheath model was constructed and electron orbits were numerically calculated. From the calculation, it was found that the electron orbit is affected by E × B drift due to the sheath electric field. Such orbit causes the broadening of the peak in the angular dependence and the dependence agrees with the experimental results. The dependence of the broadening on various plasma parameters was studied numerically and explained qualitatively by a simplified analytical model.

Local current density measurement using a Rogowski probe in Tokyo Spherical Tokamak-2

A Rogowski probe consisting of a small multi-layer Rogowski coil, five magnetic pick-up coils, and a Langmuir probe was developed to measure the local current density and its direction. It can be moved along the major radius and can be turned around its axis. This probe was used to measure the current density profile near the last closed flux surface of Ohmic plasmas in Tokyo Spherical Tokamak-2. The current density profile was measured successfully with a signal to noise ratio of greater than 20.

Demonstration of improvement in the signal-to-noise ratio of Thomson scattering signal obtained by using a multi-pass optical cavity on the Tokyo Spherical Tokamak-2

The multi-pass Thomson scattering (TS) scheme enables obtaining many photons by accumulating multiple TS signals. The signal-to-noise ratio (SNR) depends on the accumulation number. In this study, we performed multi-pass TS measurements for ohmically heated plasmas, and the relationship between SNR and the accumulation number was investigated. As a result, improvement of SNR in this experiment indicated similar tendency to that calculated for the background noise dominant situation.

Note: Multi-pass Thomson scattering measurement on the TST-2 spherical tokamak

In multi-pass Thomson scattering (TS) scheme, a laser pulse makes multiple round trips through the plasma, and the effective laser energy is enhanced, and we can increase the signal-to-noise ratio as a result. We have developed a coaxial optical cavity in which a laser pulse is confined, and we performed TS measurements using the coaxial cavity in tokamak plasmas for the first time. In the optical cavity, the laser energy attenuation was approximately 30% in each round trip, and we achieved a photon number gain of about 3 compared with that obtained in the first round trip. In addition, the temperature measurement accuracy was improved by accumulating the first three round trip waveforms.

Development of multi-channel Doppler spectroscopic measurement system using 8 × 8 multianode photomultiplier tube assembly

Using an 8 × 8 channel photomultiplier tube assembly and a single Czerny-Turner monochromator, we have developed a novel Doppler spectroscopic system which can measure the time evolutions of spectral distribution of plasma emission from eight different lines of sight simultaneously. An optical lens system is employed to couple the output of the monochromator with the detector assembly, resulting in small cross-talks less than 5% in spatial distribution together with large magnification of up to 50 in wavelength direction. The suggested system yields cost-effective polychromatic measurements of eight spatial channels with uniform optical and electrical characteristics.

First measurement of electron temperature from signal ratios in a double-pass Thomson scattering system

This paper presents an experimental demonstration to determine electron temperature (T(e)) with unknown spectral sensitivity (transmissivity) in a Thomson scattering system. In this method, a double-pass scattering configuration is used and the scattered lights from each pass (with different scattering angles) are measured separately. T(e) can be determined from the ratio of the signal intensities without knowing a real chromatic dependence in the sensitivity. Note that the wavelength range for each spectral channel must be known. This method was applied to the TST-2 Thomson scattering system. As a result, T(e) measured from the ratio (T(e,r)) and T(e) measured from a standard method (T(e,s)) showed a good agreement with <∣T(e,r) - T(e,s)∣∕T(e,s)> = 7.3%.

Hemodynamic studies of intracranial dural arteriovenous fistulas using arterial spin-labeling MR imaging

Arterial spin-labeling (ASL) magnetic resonance imaging (MRI) enables non-invasive acquisition of the brain perfusion information in cerebrovascular disease. We investigated hemodynamic changes in intracranial dural arteriovenous fistulas (DAVFs) using ASL-MRI. ASL-MRI by a Q2TIPS sequence on a 3.0-Tesla MRI was performed for three patients with Cognard's IIa+b type of DAVFs before and after treatment. Perfusion images obtained by ASL-MRI (ASL images) before treatment were visually compared with those by single-photon emission computed tomography images (SPECT images). Increasing rates of temporal changes of regional perfusion values in ASL images (ASL values) before and after treatment were also calculated. In all three patients, ASL images before treatment demonstrated high perfusion in regions around the shunting areas, where normal or low perfusion were detected on SPECT images; thus, ASL images might have demonstrated the abundant arterial shunting flow via the fistulas. On days eight to 20 after treatment, ASL values around the shunt areas remained the same or decreased, and those in the regions other than the shunt areas increased in all three patients. This might have been due to a combination of the following: a decrease in shunt flow volume, an amelioration of venous congestion, and a sustained an upward shift in the autoregulation of the brain perfusion pressure. All regional ASL values decreased on days 112 and 120 after treatment in two patients, which possibly reflects a reduction in the upward shift in autoregulation. ASL-MRI might be useful for identifying the hemodynamic behavior of DAVFs before and after treatment.

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.

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.