磁共振动态对比增强直方图分析在前列腺癌鉴别诊断中的价值

目的 探讨磁共振动态对比增强(dynamic contrast enhanced magnetic resonance imaging, DCE-MRI)定量参数直方图分析对前列腺癌检出的应用价值.方法 收集本院2016年10月至2017年6月行盆腔常规MRI、DWI和DCE-MRI扫描的患者72例,经病理证实的前列腺癌(prostate cancer,PCa)38例,前列腺增生(prostatic hyperplasia,BPH)18例,结合影像表现、实验室检查及随访观察诊断前列腺炎16例.利用第三方后处理软件(Omni Kinetic,OK),在病灶最大中心层面勾画感兴趣区,获得感兴趣区内DCE-MRI定量参数(Ktrans、Kep和Ve)的平均值及各百分位数值(5％、10％、25％、50％、75％、90％和95％),分别比较外周带PCa与前列腺炎、中央腺体PCa与BPH各参数值的差异,并分析诊断效能.结果 外周带PCa组Ktrans平均值及各百分位数值均大于前列腺炎(平均值及50％、75％、90％和95％百分位数值P＜0.05).PCa组Kep平均值及各百分位数值均大于前列腺炎(P＜0.05).外周带PCa组Ve平均值及各百分位数值小于或等于前列腺炎(5％、10％、25％和50％百分位数值P＜0.05).中央腺体PCa与BPH渗透参数Ktrans、Kep、Ve的平均值及各百分位数值差异均无统计学意义(P＞0.05).外周带PCa组Ktrans和Kep高百分位数AUC大于平均值,低百分位数AUC最小,90％ Kep诊断效能最大(AUC为0.932,敏感度78.3％,特异度92.9％);外周带PCa组Ve百分位数不具有诊断效能.结论 基于DCE-MRI的直方图分析在外周带PCa与前列腺炎鉴别诊断中具有临床价值,Ktrans、Kep高百分位数诊断效能优于平均值和低百分位数.     

An Improvement of Calculating Dose-Volume Histogram in Three-dimensional treatment Planning

剂量体积直方图（ｄｏｓｅ－ｖｏｌｕｍｅｈｉｓｔｏｇｒａｍ，简称ＤＶＨ）表示三维治疗计划中剂量与体积之间的关系，是立体定向外科中评价治疗计划好坏的重要手段。传统的ＤＶＨ算法是基于剂量域对采样点进行处理，采样众多，误差大。本文介绍一种基于体积域对采样点按剂量大小进行处理的算法，精度高，速度快，特别适用于采样点少的情况。     

Chronic inflammatory demyelinating polyneuropathy or hereditary motor and sensory neuropathy?

The pathological changes generally considered to distinguish chronic inflammatory demyelinating polyneuropathy (CIDP) from hereditary motor and sensory neuropathy (HMSN) are: mononuclear cell infiltrates, prominent endoneurial oedema, and marked fascicle-to-fascicle variability. We evaluated the diagnostic significance of these pathological features which are suggestive of CIDP. Nerve biopsies from 42 dominant HMSN type I cases with a normal disease course were investigated for the occurrence of inflammatory features. A small cluster of mononuclear cells was found in 12% of the cases and marked endoneurial oedema in 21%. Variability in pathology between the fascicles was not observed. The histogram configuration yielded additional information for differential diagnosis. Subsequently, we reviewed the clinical, electrophysiological and morphological features of 18 sporadic cases of chronic progressive demyelinating motor and sensory neuropathy with mainly classic onion bulbs in their nerve biopsies and a disease onset in the first decade. In all these patients DNA investigation for the 17p11.2 duplication was performed. According to the results of the DNA investigation, autosomal dominant HMSN type Ia was diagnosed in eight patients, although in six slight CIDP-positive features were present. A diagnosis was definite or most probable CIDP in eight patients. In two patients no definite diagnosis could be made. Testing for the presence of the 17p11.2 duplication is, therefore, helpful in distinguishing between CIDP and HMSN type I. The diagnosis of CIDP requires careful evaluation of the clinical, electrophysiological and morphological data to avoid false-positive diagnoses of inflammatory disorders.     

AV Nodal Pathways in the R‐R Interval Histogram of the 24‐Hour Monitoring ECG in Patients with Atrial Fibrillation

Background: Patients with more than one AV nodal pathway show two and more peaks in the histogram of the R‐R intervals of the Holter monitoring ECG during atrial fibrillation. It was the purpose of the present study to determine the number of patients showing more than one AV nodal pathway in a larger patient group with permanent atrial fibrillation by analyzing the Holter monitoring ECG. Methods: 250 patients with permanent atrial fibrillation during Holter monitoring ECG were studied; 203 patients had structural heart disease. The number of peaks in the R‐R interval histogram of each patient was determined. The distribution of the number of peaks in the R‐R interval histogram in different patient groups was analyzed. Results: 153 patients (61 %) had one peak, 80 patients (32%) two peaks, 13 patients (5%) three peaks, and four patients (2%) four peaks, reflecting the number of different AV nodal pathways. In the different patient groups, in the patients with or without structural heart disease, with coronary heart disease, with a history of syncope, and in patients with a mean heart rate of more than 100/min, there was no significant difference in the distribution of the number of peaks in the R‐R interval histogram. Conclusions: In more than one third of all patients with permanent atrial fibrillation there are two, three, or four AV nodal pathways. It is suggested that this number of different AV nodal pathways found in the studied group can be applied to all humans. 38.8% of all patients with permanent atrial fibrillation have more than one AV nodal pathway; 6.4% of all patients with atrial fibrillation would benefit from an ablation of AV nodal pathways with shorter refractory periods for reduction of the heart rate. A.N.E. 2001;6(4):285–289     

CEST MRI with distribution‐based analysis for assessment of early stage disease activity in a mouse model of multiple sclerosis: An initial study

Imaging biomarkers that can detect pathological changes at an early stage of multiple sclerosis (MS) may allow earlier therapeutic intervention with an improved outcome. Using a mouse model of MS, termed as experimental autoimmune encephalomyelitis (EAE), we performed chemical exchange saturation transfer (CEST) MRI at a very early stage before symptom onset (6 days post‐induction) for assessment of changes in tissues that appear “normal” with conventional MRI. The collected CEST Z‐spectra signals (S_sat/S₀) were analyzed using a histogram‐guided method to determine the contributions from various offset frequencies. Histogram analysis showed that EAE mice exhibit a more heterogeneous distribution with lower peak heights in the hindbrain compared with naïve mice at saturation offsets of 1 and 2 ppm. At these two offsets, both the mean S_sat/S₀ and the mean MTR_asym values in the cerebellum and brain stem are significantly different between EAE and naïve mice (P < 0.05). Immunofluorescent staining validated the presence of neuroinflammation, with IBA1‐positive cells detected throughout the hindbrain including the cerebellum and brain stem. Follow‐up MRI at the symptom onset (score = 1.5–2.5, 13 days post‐induction) confirmed gadolinium‐enhanced periventricular lesions. CEST Z‐spectra signals also changed by this time. The proposed three‐level histogram‐oriented analysis is simple to execute and robust for detecting subtle changes in Z‐spectra signals, which does not require a priori knowledge of damage locations or contributing offset components. CEST MRI signals at 1 and 2 ppm were sensitive to the subtle pathological changes at an early stage in EAE mice, and have potential as novel imaging biomarkers complementary to functional and physiological MRI measures.