Research progress on magnetic resonance imaging-guided proton therapy for tumors

With the application of magnetic resonance imaging (MRI)-guided photon therapy, the concept of combining real-time MRI guidance with proton therapy, namely, MRI-guided proton therapy (MRPT), has attracted widespread attention. It is expected that MRPT canmitigate the uncertaintiesduring the treatment of proton therapy to make full use of the physical advantages of protons. However, multiple electromagnetic interactions between proton therapy and MRI-guided systems may lead to mutual interference between the two systems. This article review the research progress on the MRPT system, aiming to provide certain reference for the design of MRPT system.     

针刺加重复经颅磁刺激治疗脑卒中后失眠的临床观察

目的:评价“通督调神法”针刺加重复经颅磁刺激(rTMS)治疗脑卒中后失眠的临床疗效。方法:将72例脑卒中后失眠患者随机分为2组,每组36例。对照组采用频率1 Hz、运动阈值90%的rTMS治疗,观察组在对照组rTMS治疗基础上加“通督调神法”针刺治疗。穴位取百会、神庭、印堂、风府、四神聪、神门、三阴交、申脉和照海。每日治疗1次,每周治疗5d后休息2d,共治疗4周。现察两组治疗后匹兹堡睡眠质量指数(PSQI)、焦虑自测量表(SAS)和抑部自测量表(SDS)评分改善情况,并进行两组临床疗效比较。结果:治疗4周后,两组PSQK SAS及SDS评分均降低,组内差异均有统计学意义(均P<0.001);观察组治疗后三项评分均低于对照组,组间差异均有统计学意义(P<0.05,P<0.05,P<0.001),现察组和对照组临床疗效差异有统计学意义(P<0.05)。结论:“通督调神法”针刺加rTMS治疗脑卒中后失眠疗效优于单独rTMS治疗,且能更好地改善患者焦虑、抑耶情绪。     

利用电子顺磁波谱技术研究红参对羟自由基的清除作用

目的 探索电子顺磁波谱（electron paramagnetic resonance，EPR）技术检测红参清除自由基活性的适合产生体系，并研究红参对羟自由基（?OH）的清除作用及其物质基础。方法 采用电子顺磁共振波谱仪检测不同浓度的红参提取液对?OH的体外清除作用，并用液质联用技术（LC-MS）分析红参中的主要皂苷成分，然后研究这些人参皂苷成分对?OH的清除作用。结果 确定了羟自由基的生成体系为：Fe²⁺ 0.1 mmol?L^-1、H₂O₂ 500 mmol?L^-1、DMPO 225 mmol?L^-1；不同浓度的红参提取液对?OH具有明显的清除作用，且其清除?OH的效力与浓度成正相关；LC-MS分析显示该红参提取液中主要含有Rh1、Rf、Rb3、F1、F2、Rg3、Rg5等成分，其中人参皂苷Rg5的清除自由基活性最强。结论 本研究建立了用EPR技术研究红参清除自由基活性的适合产生体系，红参具有明显的清除?OH的能力，且人参皂苷Rg5是其清除自由基的活性成分之一，确定了红参抗自由基的主要物质基础，为红参及人参皂苷Rg5的开发、应用提供了科学依据和理论基础。     

Targeted and Systematic Biopsy for Diagnosis and Management of Prostate Cancer

The value of multi-parametric magnetic resonance imaging in the detection of clinically-significant prostate cancer is increasingly well-established, and has been adopted in current diagnostic pathways and clinical guidelines. Concurrently, the role of conventional ultrasound-guided systematic prostate biopsy is increasingly questioned. In this brief review, we evaluate the continued value of systematic biopsy including a review of prospective studies on targeted and systemic biopsies in the same patients. We also address current limitations of multi-parametric magnetic resonance imaging of the prostate.     

Comparison of Cancer Detection Rates Between TRUS-Guided Biopsy and MRI-Targeted Biopsy According to PSA Level in Biopsy-Naive Patients: A Propensity Score Matching Analysis

Background

The purpose of the study was to compare cancer detection rates between 12-core transrectal ultrasound-guided prostate biopsy (TRUS-Bx) and multiparametric magnetic resonance imaging (mpMRI)-guided target prostate biopsy (MRI-TBx) according to prostate-specific antigen (PSA) level in biopsy-naive patients.

Endovascular management of multiple intracranial dural arteriovenous fistulas

Background and purposeMultiply occurring intracranial dural arteriovenous fistulas (dAVFs) have been documented but rarely occur, and neither pathogenesis nor prognosis is clearly understood. This study was conducted to analyze angiographic characteristics of multiple dAVFs and to chronicle our treatment experience.MethodsBetween April, 2002 and January, 2018, data prospectively collected from 310 patients with intracranial dAVFs were systematically reviewed, assessing clinical and anatomic outcomes of endovascular treatment in 32 patients with multiple dAVFs (≥ 2 fistulas each). Lesions were categorized as multifocal or diffuse type, depending on presentation, and further characterized as progressive or non-progressive disease.ResultsOverall, 18 patients (56.3%) experienced aggressive presentations, including intracerebral hemorrhage or venous infarction. Cortical venous reflux (CVR) was observed in 26 patients (81.3%), and sinus thrombosis or occlusion was seen in 24 (75.0%). Clinical outcomes in patients with multifocal fistulas (n = 11) were excellent (100%), marked by a moderately high rate of complete occlusion (54.5%). Those with progressive disease (n = 10) regularly displayed certain angiographic findings, namely diffuse configuration (100%), sinus thrombosis (100%), and CVR (100%). Complete anatomic obliteration was achieved in 12 patients (37.5%), and in 26 patients (81.3%), clinical outcomes were favorable.ConclusionMultiple dAVFs are typically aggressive at presentation, given strong associations with CVR and sinus thrombosis. In diffuse-type fistulas, the potential to recur or progress is high. Although definitive treatment poses a challenge, outcomes of endovascular therapeutics may be still optimized in this setting through strategic procedural modifications and careful follow-up monitoring.     

Synthetic MRI is not yet ready for morphologic and functional assessment of patellar cartilage at 1.5 Tesla

PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences.