Amide proton transfer-weighted imaging with a short acquisition time based on a self B0 correction using the turbo spin echo-Dixon method: A phantom study.

PURPOSE: Conventional amide proton transfer (APT)-weighted imaging requires a chemical exchange saturation transfer (CEST) sequence with multiple saturation frequency offsets and a B0 correction sequence, plus a long acquisition time that can be reduced by applying the conventional method using CEST images with seven radiation pulses (i.e., the seven-points method). For a further reduction of acquisition times, we propose fast two-dimensional (2D) APT-weighted imaging based on a self B0 correction using the turbo spin echo (TSE)-Dixon method. We conducted a phantom study to investigate the accuracy of TSE-Dixon APT-weighted imaging. METHODS: We prepared two types of phantoms with six samples for a concentrationdependent evaluation and a pH-dependent evaluation. APT-weighted images were acquired by the conventional, seven-points, and TSE-Dixon methods. Linear regression analyses assessed the dependence between each method's APT signal intensities (SIs) and the concentration or pH. We performed a one-way analysis of variance with Tukey's honestly significant difference post hoc test to compare the APT SIs among the three methods. The agreement of the APT SIs between the conventional and seven-points or TSE-Dixon methods was assessed by a Bland- Altman plot analysis. RESULTS: The APT SIs of all three acquisition methods showed positive concentration dependence and pH dependence. No significant differences were observed in the APT SIs between the conventional and TSE-Dixon methods at each concentration. The Bland-Altman plot analyses showed that the APT SIs measured with the seven-points method resulted in 0.42% bias and narrow 95% limits of agreement (LOA) (0.93%-0.09%) compared to the conventional method. The APT SIs measured using the TSE-Dixon method showed 0.14% bias and similar 95% LOA (-0.33% to 0.61%) compared with the seven-points method. The APT SIs of all three methods showed positive pH dependence. At each pH, no significant differences in the APT SIs were observed among the methods. Bland-Altman plot analyses showed that the APT SIs measured with the seven-points method resulted in low bias (0.03%) and narrow 95% LOA (-0.30% to 0.36%) compared to the conventional method. The APT SIs measured by the TSE-Dixon method showed slightly larger bias (0.29%) and similar 95% LOA (from -0.15% to 0.72%) compared to those measured by the seven-points method. CONCLUSION: These results demonstrated that our proposed method has the same concentration dependence and pH dependence as the conventional method and the seven-points method. We thus expect that APT-weighted imaging with less influence of motion can be obtained in clinical examinations.

Improved temporal resolution and acceleration on 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) using an interpolation algorithm on the temporal axis and compressed sensing-sensitivity encoding (CS-SENSE).

PURPOSE: Two major drawbacks of 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) are the low temporal resolution and long scanning time. We investigated the feasibility of increasing the temporal resolution and accelerating the scanning time on 4D-S-PACK by using CS-SENSE and PhyZiodynamics, a novel image-processing program that interpolates images between phases to generate new phases and reduces image noise. METHODS: Seven healthy volunteers were scanned with a 3.0 T MR scanner to visualize the internal carotid artery (ICA) system. PhyZiodynamics is a novel image-processing that interpolates images between phases to generate new phases and reduces image noise, and by increasing temporal resolution using PhyZiodynamics, inflow dynamic data (reference) were acquired by changing the labeling durations (100-2000 msec, 31 phases) in 4D-S-PACK. From this set of data, we selected seven time intervals to calculate interpolated time points with up to 61 intervals using ×10 for the generation of interpolated phases with PhyZiodynamics. In the denoising process of PhyZiodynamics, we processed the none, low, medium, high noise reduction dataset images. The time intensity curve (TIC), the contrast-to-noise ratio (CNR) were evaluated. In accelerating with CS-SENSE for 4D-S-PACK, 4D-S-PACK were scanned different SENSE or CS-SENSE acceleration factors: SENSE3, CS3-6. Signal intensity (SI), CNR, were evaluated for accelerating the 4D-S-PACK. With regard to arterial vascular visualization, we evaluated the middle cerebral artery (MCA: M1-4 segments). RESULTS: In increasing temporal resolution, the TIC showed a similar trend between the reference dataset and the interpolated dataset. As the noise reduction weight increased, the CNR of the interpolated dataset were increased compared to that of the reference dataset. In accelerating 4D-S-PACK, the SI values of the SENSE3 dataset and CS dataset with CS3-6 were no significant differences. The image noise increased with the increase of acceleration factor, and the CNR decreased with the increase of acceleration factor. Significant differences in CNR were observed between acceleration factor of SENSE3 and CS6 for the M1-4 (P < 0.05). Visualization of small arteries (M4) became less reliable in CS5 or CS6 images. Significant differences were found for the scores of M2, M3 and M4 segments between SENSE3 and CS6. CONCLUSION: With PhyZiodynamics and CS-SENSE in 4D-S-PACK, we were able to shorten the scan time while improving the temporal resolution.

Effect of Saturation Pulse Duration and Power on pH-weighted Amide Proton Transfer Imaging: A Phantom Study.

PURPOSE: Amide proton transfer (APT) imaging may detect changes in tissues' pH based on the chemical exchange saturation transfer (CEST) phenomenon, and thus it may be useful for identifying the penumbra in ischemic stroke patients. We investigated the effect of saturation pulse duration and power on the APT effect in phantoms with different pH values. METHODS: Five samples were prepared from a 1:10 solution of egg-white albumin in phosphate-buffered saline at pH 6.53-7.65. The APT signal intensity (SI) was defined as asymmetry of the magnetization transfer ratio at 3.5 ppm. We measured the APT SIs in the egg-white albumin samples of different pH values with saturation pulse durations of 0.5, 1.0, 2.0, and 3.0 sec and saturation pulse powers of 0.5, 1.5, and 2.5 µT. The relative change in the APT SI in relation to the saturation duration and power at different pH values was defined as follows: (APT SI each saturation pulse - APT SI shortest or weakest pulse)/APT SIshortest or weakest pulse. The dependence of the APT SI on pH and the relative change in the APT SI were calculated as the slope of the linear regression. RESULTS: The lower the pH, the larger the relative change in the APT SI, due to the change in saturation pulse duration and power. The APT SI was highly correlated with the pH at all saturation pulse durations and powers. CONCLUSION: The influence of saturation duration and power on the APT effect was greater at lower pH than higher pH. The combination of saturation pulse ≥ 1.0 s and power ≥ 1.5 µT was useful for the sensitive detection of changes in APT effects in the egg-white albumin samples with different pH values.

High-resolution magnetic resonance imaging of the triangular fibrocartilage complex using compressed sensing sensitivity encoding (SENSE).

PURPOSE: To evaluate the optimal sequence for high-resolution magnetic resonance imaging (MRI) of the triangular fibrocartilage complex (TFCC) using compressed sensing-sensitivity encoding (CS-SENSE). METHODS: Three-dimensional fast field echo T2-weighted images were obtained from 13 healthy volunteers using the original, high spatial resolution sequence with CS-SENSE [HR (CS-SENSE)] and without CS-SENSE (HR) and super-high spatial resolution sequence with CS-SENSE [S-HR (CS-SENSE)] and without CS-SENSE (S-HR). For qualitative analysis, the number of patients affected by motion artifacts in each sequence was counted, and the visualization of the TFCC anatomic structures and overall image quality were categorized. For the quantitative analysis, relative signal intensity (SI) and relative contrast of the lunate bone marrow, lunate cartilage, and disk proper in the wrist joint were all calculated. RESULTS: The HR (CS-SENSE) sequence showed better visualization scores than the original sequence in the triangular ligament at the ulnar styloid tip, dorsal radioulnar ligament, and ulnotriquetral ligament. Similarly, the S-HR (CS-SENSE) sequence showed better visualization scores than the original sequence in the triangular ligament at the ulnar styloid tip and dorsal radioulnar ligament. Overall image quality scores were not significantly different, and motion artifacts in the HR and S-HR sequences were observed in 3 of the 13 patients. In contrast, the original sequence showed higher values than those in the HR (CS-SENSE) and S-HR (CS-SENSE) sequences in relative SI of the bone marrow and relative contrast of the cartilage-bone marrow and cartilage-disk proper. CONCLUSIONS: Out of the three sequences, the HR (CS-SENSE) sequence provided the highest visualization score and diagnostically sufficient image quality score, although relative SI and relative contrast were low. The HR (CS-SENSE) sequence may be clinically useful for imaging TFCCs.

Optimization of 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) for vessel-selective visualization of the internal carotid artery and vertebrobasilar artery systems.

PURPOSE: This study investigated the optimal labeling position and gradient moment for 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) for vessel-selective flow visualization of the internal carotid artery (ICA) and vertebrobasilar artery (VBA) systems. METHODS: Seven healthy volunteers were scanned with a 3.0 T MR scanner. To visualize the ICA system, the labeling focus was placed in the right ICA at 55, 75 and 95 mm below the imaging slab. To visualize the VBA system, the labeling focus was placed in the basilar artery (BA), upper vertebral artery (VA upper), and lower vertebral artery (VA lower). Two sizes of labeling focus were created using gradient moments of 0.5 and 0.75 mT/m ms. The contrast-to-noise ratio (CNR) was measured in the middle cerebral artery (MCA) and posterior cerebral artery (PCA) branches. RESULTS: CNRs increased as the distance between the center of the imaging slab and the labeling position decreased in all MCA segments. CNRs obtained with VA lower tended to be higher than those obtained with BA and VA upper in all PCA segments. Selective vessel visualization was achieved with the gradient moment of 0.75 mT/m ms for the ICA and VBA system. CONCLUSION: The optimal 4D-S-PACK gradient moment was found to be 0.75 mT/m ms for the ICA and VBA systems. When visualizing the ICA system, the labeling position should be placed as close as possible to the imaging slab. When visualizing the VBA system, the labeling position should be placed at VA lower .

Clinical features and mechanism of liver injury in patients with mild or moderate coronavirus disease 2019.

BACKGROUND AND AIM: We aimed to identify clinical features that suggest that coronavirus disease 2019 (COVID-19) should be a differential diagnosis in patients presenting with a chief complaint of fever and abnormal liver function. METHODS: We retrospectively studied the presence or absence of abnormal liver function in 216 patients diagnosed with mild-moderate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection between February and September 2020. RESULTS: Abnormal liver function was observed in 51 patients with mild-moderate COVID-19. The median peak aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were 57.5, 75.5, and 332.5 U/L, respectively. The median number of days from symptom onset to peak AST, ALT, and LDH were 8.5, 9, and 8.5, respectively. The median peak LDH/AST ratio was 9.0. Low lymphocyte-to-white blood cell ratio and elevated LDH were found to be independent contributing factors for intensive care unit (ICU) admission on a multivariate analysis. CONCLUSIONS: AST-predominant AST/ALT/LDH elevation peaking 8-9 days after symptom onset and not accompanied by elevated alkaline phosphatase or gamma-glutamyl transferase may be a useful clinical feature for differentiating COVID-19 from other diseases. Since the median LDH/AST ratio was 9.0, it seems that the abnormal liver function caused by SARS-CoV-2 is an indirect damage to liver cells due to elevated cytokine levels caused by liver-infiltrating lymphocytes. SARS-CoV-2 infection should be considered in patients presenting with a chief complaint of fever and liver injury; those with a high lymphocyte-to-white blood cell ratio or and a high LDH/AST ratio may be admitted to the ICU.

Optimization of the refocusing flip angle in the characterization of cerebrospinal fluid dynamics using multi-spin echo acquisition cine imaging (MUSACI).

PURPOSE: Multi-spin echo acquisition cine imaging (MUSACI) is a method used for cerebrospinal fluid (CSF) dynamics imaging based on the proton phase dispersion and flow void using 3D multi-spin echo imaging. In a previous study, the refocusing flip angle of MUSACI was set at a constant 80°. We conducted the present study to investigate the preservation the CSF signal intensity even in a long echo train and improve the ability to visualize CSF movement by modifying the refocusing flip angle in MUSACI. METHODS: The MUSACI images were acquired in 10 healthy volunteers (7 men and 3 women; age range 24-44 years; mean age 29.4 ±â€¯6.2 years) with a 3.0 Tesla MR scanner. Five refocusing flip angle sets were applied: constant 30°, constant 50°, constant 80°, pseudo-steady state (PSS) 50°-70°-100° (PSS50°), and PSS80°-100°-130° (PSS80°). In all sequences, the in-plane spatial resolution was 0.58 × 0.58 mm2, and the CSF movement for one heartbeat was drawn at 80-msec intervals. The signal intensity (SI) of CSF in the lateral ventricle, the foramen of Monro, the third ventricle, the fourth ventricle, and the pons was measured on MUSACI. Pearson's correlation coefficient was calculated between the CSF SI and effective echo time (TE; TEeff) in the lateral ventricle. RESULTS: Both antegrade and retrograde CSF movements on the midsagittal MUSACI images and the retrograde CSF movement in the foramen of Monro was observed in all sequences with the constant flip angles. A strong reverse correlation between the CSF SI in the lateral ventricle and TEeff values was observed with constant 30° (r = -0.96, p < 0.01), constant 50° (r = -0.97, p < 0.01) and constant 80° (r = -0.88, p < 0.01). A weak positive correlation was observed with PSS50° (r = 0.28, p = 0.43), and a moderate reverse correlation was observed at PSS80° (r = -0.60, p = 0.07). The SI values of the foramen of Monro, the third ventricle, and the fourth ventricle were significantly lower than that of the lateral ventricle, and those values were higher than that of the pons in both the constant 80° sequence and the PSS 50° sequence. CONCLUSION: PSS50° could be the optimal flip angle scheme for MUSACI, because the SI changes due to CSF movement and the SI preservation due to a long echo train were large due to the use of the refocusing flip angle method.

Single-Drug Approach with Edoxaban is Effective for Resolving Non-Acute Cancer-Associated Venous Thrombosis: A Single-Arm Retrospective Analysis.

Recently, cancer-related venous thromboembolism (VTE) has been termed "cancer-associated thrombosis (CAT)" and is the focus of current research. We retrospectively investigated the efficacy of a single-drug approach with edoxaban for the treatment of non-acute CAT. Thirty-two non-acute CAT patients who received edoxaban were analyzed. The primary endpoint of this analysis was the thrombus disappearance rate at the first evaluation. Secondary endpoints included progression/recurrence of VTE, major bleeding, and D-dimer levels. The thrombus disappearance rate was 62.5%. Therefore, the null hypothesis for the primary endpoint (thrombus disappearance rate of ≤32.0%) was rejected (p = 0.00038) based on the rate of the previous study as the historical control. Recurrent VTE and major bleeding occurred in two patients each. After the start of treatment with edoxaban, a significant difference in D-dimer levels was observed (p = 0.00655). We demonstrated that a single-drug approach with edoxaban is a potential treatment option for non-acute CAT.

Variants of carboxylesterase 1 have no impact on capecitabine pharmacokinetics and toxicity in capecitabine plus oxaliplatin treated-colorectal cancer patients.

PURPOSE: Capecitabine is a prodrug that undergoes metabolism in three steps to form an active 5-fluorouracil (5-FU). The first step is primarily catalyzed by liver carboxylesterases (CES) 1. Here, we examined the effects of CES1 variants on pharmacokinetics and toxicity of capecitabine. METHODS: We enrolled postoperative colorectal cancer (CRC) patients administered with adjuvant capecitabine plus oxaliplatin (CapeOX) and metastatic CRC patients receiving CapeOX. The pharmacokinetic analysis of the first capecitabine dose (1000 mg/m2) was done on day 1, and oxaliplatin administration was shifted to day 2. Plasma concentrations of capecitabine, 5'-deoxy-5-fluorocytidine, 5'-deoxy-5-fluorouridine (5'-DFUR), and 5-FU were analyzed by high-performance liquid chromatography. CES1 polymorphisms (rs3217164, rs2244614, rs2244613, rs7187684, and rs11861118) and the functional CES1 genes (1A1, var1A1, 1A2, and pseudo 1A3) in their diplotype configurations were analyzed by direct sequencing. RESULTS: Thirty-seven patients were enrolled from September 2017 to February 2020. Patients with a higher area under the plasma concentration-time curve to capecitabine dose ratio (AUC/dose) of 5'-DFUR than its mean showed a higher frequency of overall ≥ grade 3 toxicity and lower relative dose intensity (RDI) of capecitabine than those with a lower ratio. Higher CES1 activity expressed as a metabolic ratio (AUC of capecitabine/sum of three AUCs of each metabolite) lower than its mean was associated with higher 5'-DFUR AUC/dose and lower RDI, indicating essential roles of CES1 in capecitabine activation to produce 5'-DFUR. However, the association between CES1 variants and capecitabine pharmacokinetics and toxicity was not significant. CONCLUSION: CES1 variants are not associated with capecitabine pharmacokinetics and toxicity.

Human leukocyte antigen in Japanese patients with idiopathic inflammatory myopathy.

Objective: The human leukocyte antigen (HLA) is the strongest genetic risk factor for idiopathic inflammatory myopathy (IIM), and different HLA alleles have been reported to be associated with IIM susceptibility among different ethnic groups. In this study, we have investigated HLA alleles associated with IIM in Japanese patients.Methods: Genotyping of HLA-DRB1 and DPB1 were performed in 252 Japanese IIM patients (166 dermatomyositis [DM] and 86 polymyositis [PM] patients) and the association was analyzed with comparison to controls (n = 1026 for DRB1 and n = 413 for DPB1).Results: DRB1*08:03 was associated with IIM (p = 1.60 × 10-5, pc = .0005, odds ratio [OR] 2.11, 95% confidence interval [CI] 1.52-2.92) and DM (p = .0004, pc = .0128, OR 2.06, 95%CI 1.40-3.02). DPB1*05:01 was also associated with IIM (p = .0001, pc = .0021, OR 1.96, 95%CI 1.38-2.77) and DM (p = .0005, pc = .0075, OR 2.05, 95%CI 1.37-3.08). DRB1*09:01 (p = .0012, pc = .0368, OR 0.35, 95% CI 0.18-0.69) and DPB1*04:01(p = .0004, pc = .0057, OR 0.05, 95% CI 0.00-0.85) were protectively associated with PM. Two locus analyses suggested that DRB1*09:01 and DPB1*04:01 were independently associated with PM.Conclusion: Protective associations of HLA were detected in Japanese PM patients.

VEGF Inhibitors Do Not Increase D-dimer Levels in Colorectal Cancer Patients Without Venous Thromboembolism: A Retrospective Non-inferiority Analysis

BACKGROUND/AIM: If VEGF inhibitors contribute to an increase in D-dimer levels, they may adversely affect the diagnosis of venous thromboembolism (VTE). Consequently, this retrospective study examined the effects of VEGF inhibitors on D-dimer levels in colorectal cancer patients. PATIENTS AND METHODS: A total of 104 colorectal cancer patients who received chemotherapy, were included in this study. To perform D-dimer analysis, patients were divided into two analysis targets: patients with VTE and without VTE. Statistical analysis included a natural logarithmic transformation of D-dimer data. RESULTS: In the D-dimer analysis of non-VTE patients, the natural logarithm D-dimer mean difference was -0.186, with a 95% CI of -0.525 to 0.154. The upper limit of the 95%CI (0.154) did not exceed the non-inferiority margin (Δ) of 0.199, and therefore met the non-inferiority criteria. CONCLUSION: VEGF inhibitors don't contribute to increased D-dimer levels in colorectal cancer patients without VTE.

Dose down-titration of biological disease-modifying antirheumatic drugs in daily clinical practice: Shared decision-making and patient treatment preferences in Japanese patients with rheumatoid arthritis.

AIM: To determine characteristics of rheumatoid arthritis (RA) patients in Japan who received the same biological disease-modifying antirheumatic drugs (bDMARDs) for at least 6 months and to identify factors associated with successful down-titration of bDMARDs dependent on shared decision-making. METHODS: We included consecutive RA patients who received the same bDMARD with low disease activity or remission for at least 6 months in our two university hospitals. Patients treated with the bDMARD standard dose were defined as SD, while those treated with bDMARD down-titration were defined as DT. We retrospectively reviewed clinical charts and compared data between the two groups. RESULTS: Of 288 patients with RA, 204 (70.8%) and 84 (29.2%) continued standard dose treatment and underwent down-titration treatment, respectively. Sixty-six of 84 (78.6%) down-titration-treated patients continued to show low disease activity or remission, whereas 18 (21.4%) relapsed 18.9 ± 24.4 months after bDMARD down-titration was started. Univariate predictor analysis showed that the probable factors of down-titration were no history of bDMARD treatment (P = .001) and low initial Disease Activity Assessment of 28 joint score (P = .048). Other clinical characteristics had no significant relationship with successful down-titration. CONCLUSIONS: Thus, bDMARD-naïve patients and those with low initial disease activity are more likely to agree to attempt down-titration. However, the timing and method of down-titration should be made in shared decision-making between patients and rheumatologists.

Two cases of lymphangitic carcinomatosis as the primary symptom of colorectal carcinoma that achieved complete remission using combination anti-EGFR antibody therapy.

Clinicians often encounter cases of pulmonary lymphangitic carcinomatosis when treating patients with cancer. When such a condition develops before the diagnosis of cancer, its diagnosis is often challenging. Herein, we report about two patients with colorectal carcinoma diagnosed after the identification of lymphangitic carcinomatosis, which achieved complete remission with combination anti-epidermal growth factor receptor (anti-EGFR) antibody therapy. In case 1, a 74-year-old woman presented with cough and dyspnea that had persisted for 1 month. She had unresectable advanced carcinoma of the sigmoid colon with lymphangitic carcinomatosis. Her respiratory status gradually deteriorated due to the disease. Thus, FOLFIRI plus cetuximab therapy was initiated. Her dyspnea rapidly resolved with the treatment, and complete remission of lymphangitic carcinomatosis was achieved. In case 2, a 46-year-old man presented with fever and dyspnea that had persisted for 1 month. He had unresectable advanced carcinoma of the transverse colon with lymphangitic carcinomatosis. FOLFOXIRI therapy was then initiated. However, his respiratory status did not improve. Therefore, his treatment was immediately switched to FOLFIRI plus panitumumab. His dyspnea rapidly resolved with the treatment, and complete remission of lymphangitic carcinomatosis was achieved. In oncologic emergencies, such as lymphangitic carcinomatosis, requiring an early response to treatment, the administration of anti-EGFR antibodies may be a highly effective treatment option.

Trastuzumab With S-1 Plus Cisplatin in HER2-positive Advanced Gastric Cancer Without Measurable Lesions: OGSG 1202.

BACKGROUND/AIM: Trastuzumab with S-1 plus cisplatin was proved to be effective for human epidermal growth factor receptor type 2 (HER2)-positive advanced gastric cancer with measurable lesions. However, the efficacy and safety of this regimen in the absence of measurable lesions are unknown. PATIENTS AND METHODS: Patients with HER2-positive gastric cancer without measurable lesions received cisplatin plus trastuzumab intravenously on day 1 and oral S-1 on days 1-14 of a 21-day cycle. The primary end-point was overall survival, and 40 patients were planned to be enrolled. RESULTS: Fifteen patients were enrolled. The median overall survival was 14.4 months. The 1- and 3-year overall survival rates were 66.7 % and 26.7 %, respectively. Major grade 3-4 adverse events included neutropenia (47%), anemia (40%), diarrhea (20%), nausea (20%), and anorexia (20%). CONCLUSION: Trastuzumab with S-1 plus cisplatin might be effective and tolerable for HER2-positive advanced gastric cancer without measurable lesions.

Visualization of cerebrospinal fluid dynamics using multi-spin echo acquisition cine imaging (MUSACI).

PURPOSE: To evaluate the visualization of CSF dynamics using the novel method multi-spin echo acquisition cine imaging (MUSACI). METHODS: MUSACI is based on multi-echo volume isotropic turbo spin-echo acquisition (VISTA) with pulse gating. MUSACI images were acquired in 11 healthy volunteers (7 men, 4 women; age range, 24-46 y, mean age, 31.9 ± 5.51 y). We compared the CSF signal intensities (SIs) at multiple values of the effective echo time (TEeff ) at the lateral ventricle, the foramen of Monro, the third ventricle, and the fourth ventricle. We compared the CSF SI changes in MUSACI at multiple TEeff and the mean velocities in phase contrast (PC) at each trigger delay at the foramen of Monro, the third ventricle, and the fourth ventricle. RESULTS: The anterograde CSF motion from the aqueduct to the fourth ventricle, the retrograde motion from the aqueduct to the third ventricle, and the retrograde motion from the foramen of Monro to the lateral ventricle were observed with MUSACI. The CSF SIs at each TEeff in the foramen of Monro, the third ventricle, and the fourth ventricle were significantly lower than that at each TEeff in the lateral ventricle (P < 0.05). The CSF SI in MUSACI changed with the TEeff , and the CSF movements were observed at each trigger delay in PC. CONCLUSION: MUSACI can provide both high-resolution anatomical detail of the CSF passageways and physiologic information regarding CSF dynamics in a single scan.

Improved Visualization of Middle Ear Cholesteatoma with Computed Diffusion-weighted Imaging.

Computed DWI (cDWI) is a mathematical technique that calculates arbitrary higher b value images from at least two different lower b values. In addition, the removal of high intensity noise with image processing on cDWI could improve cholesteatoma-background contrast-to-noise ratio (CNR). In the present study, noise reduction was performed by the cut-off values of apparent diffusion coefficient (ADC) less than 0 and 0.4 × 10-3 s/mm2. The cholesteatoma to non-cholesteatoma CNR was increased using a noise reduction algorithm for clinical setting.

The predictive prognostic factors for polymyositis/dermatomyositis-associated interstitial lung disease.

BACKGROUND: Interstitial lung disease (ILD) is the principal cause of death in polymyositis/dermatomyositis (PM/DM). Here we investigated prognostic factors for death and serious infection in PM/DM-ILD using the multicenter database. METHODS: We retrospectively reviewed baseline demographic, clinical and laboratory findings, treatment regimens and outcomes in patients with PM/DM-ILD. The distribution of ILD lesions was evaluated in four divided lung zones of high-resolution computed tomography images. RESULTS: Of 116 patients with PM/DM-ILD, 14 died within 6 months from the diagnosis. As independent risk factors for early death, extended ILD lesions in upper lung fields (odds ratio (OR) 8.01, p = 0.016) and hypocapnia (OR 6.85, p = 0.038) were identified. Serious infection was found in 38 patients, including 11 patients who died of respiratory or multiple infections. The independent risk factors were high serum KL-6 (OR 3.68, p = 0.027), high initial dose of prednisolone (PSL) (OR 4.18, p = 0.013), and combination immunosuppressive therapies (OR 5.51, p < 0.001). CONCLUSION: The present study shows the progression of ILD at baseline is the most critical for survival and that infection, especially respiratory infection, is an additive prognostic factor under the potent immunosuppressive treatment.

Diagnostic test accuracy of ultrasound for synovitis in rheumatoid arthritis: systematic review and meta-analysis.

Objective: To evaluate diagnostic test accuracy of US compared with MRI for the detection of synovitis in RA patients. Methods: A systematic literature search was performed in the PubMed, EMBASE, Cochrane Library and Web of Science Core Collection databases. Studies evaluating the diagnostic test accuracy of US for synovitis detected by MRI as the reference standard for wrist, MCP, PIP and knee joints were included. To assess the overall accuracy, we calculated the diagnostic odds ratio using a DerSimonian-Laird random effects model and the area under the curve (AUC) for the hierarchical summary receiver operating characteristics using Holling's proportional hazards models. The summary estimate of the sensitivity and specificity were obtained using the bivariate model. Results: Fourteen of 601 identified articles were included in the review. The diagnostic odds ratio was 11.6 (95% CI 5.6, 24; I2 = 0%), 28 (95% CI 12, 66; I2 = 11%), 23 (95% CI 6.5, 84; I2 = 19%) and 5.3 (95% CI 0.60, 48; I2 = 0%) and the AUC was 0.81, 0.91, 0.91 and 0.61 for wrist, MCP, PIP and knee joints, respectively. The summary estimates of sensitivity and specificity were 0.73 (95% CI 0.51, 0.87)/0.78 (95% CI 0.46, 0.94), 0.64 (95% CI 0.43, 0.81)/0.93 (95% CI 0.88, 0.97), 0.71 (95% CI 0.33, 0.93)/0.94 (95% CI 0.89, 0.97) and 0.91 (95% CI 0.56, 0.99)/0.60 (95% CI 0.20, 0.90) for wrist, MCP, PIP and knee joints, respectively. Conclusion: US is a valid and reproducible technique for detecting synovitis in the wrist and finger joints. It may be considered for routine use as part of the standard diagnostic tools in RA.

Glycosaminoglycan chemical exchange saturation transfer in human lumbar intervertebral discs: Effect of saturation pulse and relationship with low back pain.

PURPOSE: To evaluate the dependence of saturation pulse power and duration on glycosaminoglycan chemical exchange saturation transfer (gagCEST) imaging and assess the degeneration of human lumbar intervertebral discs (IVDs) using this method. MATERIALS AND METHODS: All images were acquired on a 3T magnetic resonance imaging (MRI) scanner. The CEST effects were measured in the glycosaminoglycan (GAG) phantoms with different concentrations. In the human study, CEST effects were measured in the nucleus pulposus of IVD. We compared the CEST effects among the different saturation pulse powers (0.4, 0.8, and 1.6 µT) or durations (0.5, 1.0, and 2.0 sec) at each Pfirrmann grade (I-V). The relationship between the CEST effects and low back pain was also evaluated. RESULTS: The phantom study showed high correlations between the CEST effects and GAG concentration (R2 = 0.863, P < 0.0001, linear regression). In the human study, the CEST effect obtained with the 0.8 µT power was significantly greater than those obtained with 0.4 (P < 0.01) and 1.6 µT power (P < 0.05) at Pfirrmann grade I. The CEST effect obtained with a 1.0-sec duration was significantly greater than those derived with 0.5 and 2.0 sec (P < 0.01) durations at Pfirrmann grades I and II. The CEST effects in the group with moderate low back pain were significantly lower than those in the groups without pain (P < 0.001) and with mild pain (P = 0.0216). CONCLUSION: The contrast of gagCEST imaging in the lumbar IVDs varied with saturation pulse power and duration. GagCEST imaging may serve as a tool for evaluating IVD degeneration in the lumbar spine. LEVEL OF EVIDENCE: 2 J. Magn. Reson. Imaging 2017;45:863-871.