扩散峰度成像对高级别胶质瘤及单发脑转移瘤的鉴别诊断价值

【摘要】目的：探讨磁共振扩散峰度成像（DKI）的多参数值对高级别胶质瘤（HGG）和单发脑转移瘤（SBM）的鉴别诊断价值。方法：搜集经手术病理或临床随访证实的19例HGG患者和14例SBM患者的病例资料,术前均行常规MRI扫描、DKI扫描及增强扫描。选取兴趣区（ROI）测定其DKI参数,并进行矫正处理得到各向异性分数（FA）、平均扩散（MD）及平均峰度（MK）值。应用独立样本t检验对两组间各参数值进行统计学分析,绘制ROC曲线计算敏感度、特异度及曲线下面积（AUC）。结果：两组肿瘤实质区DKI各参数值差异无统计学意义（P＞0.05）;而瘤周区的FA值、MD值及MK值在两组间的差异有统计学意义（P＜0.05）。ROC曲线分析显示,瘤周区的MK值鉴别两种肿瘤的敏感度和特异度较FA值和MD值高,曲线下面积最大。结论：瘤周区的FA值、MD值及MK值对HGG和SBM有良好的鉴别诊断价值,且瘤周区MK值诊断效能最高。     

弥散张量成像鉴别高级别胶质瘤与单发转移瘤的价值

目的：探讨弥散张量成像鉴别脑内原发高级别胶质瘤与单发转移瘤的价值。材料和方法：测量行DTI检查的13例幕上高级别胶质瘤、8例单发转移瘤的肿瘤实质、瘤周水肿区及在大脑脚层面双侧皮质脊髓束的ADC值、FA值，并计算患侧／对侧FA相对值，行统计学分析。结果：单发转移瘤瘤周水肿区ADC值明显高于高级别胶质瘤瘤周水肿区ADC值；两者大脑脚层面患侧皮质脊髓束FA值轻度降低，ADC值无明显差异；相对FA值高级别胶质瘤较低。结论：瘤周水肿区ADC值对高级别胶质瘤与单发转移瘤的鉴别有意义；弥散张量成像提供更多瘤周受累纤维束病理改变的信息。     

MR灌注成像在鉴别单发脑转移瘤与高级别胶质瘤中的价值

目的探讨MR灌注成像在鉴别单发脑转移瘤与高级别胶质瘤中的作用及价值。方法对10例单发脑转移瘤和15例高级别胶质瘤患者行手术前MR灌注成像扫描。分析其MR灌注曲线及伪彩图像,测量肿瘤实质部分及瘤周水肿区最大相对脑血容积(rCBV)值及相应部位相对平均通过时间(rMTT)数值并将所测值进行t检验。结果单发脑转移瘤的MR灌注曲线形态和伪彩图像中的色彩特点与高级别胶质瘤有明显区别。单发脑转移瘤与高级别胶质瘤肿瘤实质部分的最大rCBV值分别为3.70±2.34、6.01±2.17,瘤周水肿区则分别为0.80±0.28、1.77±1.19。单发脑转移瘤与高级别胶质瘤肿瘤实质相应部位的rMTT值分别为1.17±0.39、1.11±0.18,瘤周水肿区则分别为1.17±0.38、1.02±0.20。两者肿瘤实质部分和瘤周水肿区的rCBV值均数之间差异有统计学意义(P<0.05),而相应的rMTT值均数之间差异没有统计学意义(P>0.05)。结论MR灌注成像对术前鉴别单发脑转移瘤与高级别胶质瘤有临床实用价值。     

磁共振弥散张量成像在脑高级别星形细胞瘤和转移瘤瘤周实质区的诊断价值

目的 探讨磁共振弥散张量成像(diffusion tensor imaging,DTI)在高级别星形细胞瘤和单发脑转移瘤诊断中的价值.方法 25例脑高级别星形细胞瘤和16例单发脑转移瘤,术前行DTI扫描,测定瘤周脑实质区及对侧正常脑实质的平均弥散系数(MD)值及各向异性分数(FA)值,并重建白质纤维示踪图,观察病灶与白质纤维束的关系.结果 高级别星形细胞瘤与脑转移瘤瘤周实质区的FA值分别为0.227±0.05、0.169±0.07,两者存在统计学差异(P＜0.05).DTI白质纤维示踪图可以较为准确地反映病灶与白质纤维束的关系.结论瘤周实质区FA值有助于高级别脑星形细胞瘤与转移瘤的鉴别.     

弥散张量成像在高级别胶质瘤与转移瘤中的鉴别诊断价值初探

目的 探讨弥散张量成像(DTI)在高级别胶质瘤与转移瘤中的鉴别诊断价值.方法 收集经手术病理证实13例高级别胶质瘤与13例转移瘤,均做了磁共振DTI,获得平均弥散系数(MD)图及部分各向异性指数(FA)图,分别测定2组肿瘤实质区、囊变坏死区、瘤周区及正常白质区MD值、FA值,分析比较2组肿瘤实质区、囊变坏死区、瘤周区MD值、FA值有无统计学差异.结果 胶质瘤肿瘤实质区、囊变坏死区、瘤周区MD值分别为(0.976±0.171)×10-9mm2/s、(1.92±0.515)×10-9mm2/s、(1.41±0.288)×10-9mm2/s,转移瘤上述3个区MD值分别为(1.12±0.364)×10-9mm2/s、(1.72±0.646)×10-9mm2/s、(1.66±0.164)×10-9mm2/s,2组肿瘤实质区、囊变坏死区MD值比较无统计学差异(P>0.05),胶质瘤瘤周区MD值低于转移瘤(P<0.05);胶质瘤肿瘤实质区、囊变坏死区、瘤周区FA值分别为0.137±0.056、0.084±0.061、0.148±0.090,转移瘤上述3个区FA值分别为0.140±0.0778、0.0702±0.0265、0.126±0.0567,2组肿瘤实质区、囊变坏死区、瘤周区FA值比较均无统计学差异(P>0.05).结论 通过测定瘤周区MD值,DTI有助于高级别胶质瘤与转移瘤的鉴别诊断.     

磁共振扩散峰度成像在第四脑室肿瘤鉴别诊断中的应用价值

目的应用扩散峰度磁共振(MR)成像技术探定第四脑室肿瘤内部成分及细胞增殖状态,分析其各成像参数与Ki-67的相关性,同时分析扩散峰度成像各参数在鉴别四脑室区髓母细胞瘤、室管膜瘤中的应用价值。方法收集21例四脑室区肿瘤患者,术前行常规磁共振成像(MRI)及扩散峰度成像(DKI)序列扫描。术后对标本进行S-P染色法检测Ki-67的表达,应用扩散峰度评估软件(DKE)测定肿瘤实质区平均扩散峰度(MK)、径向峰度(Kr)、轴向峰度(Ka)及平均扩散系数(MD)值、各向异性系数(FA)值。Spearman相关分析研究DKI各参数值与Ki-67的相关性,应用独立样本t检验,比较髓母细胞瘤和室管膜瘤DKI参数值的差异性,并通过ROC曲线分析MK值、FA值和MD值在鉴别诊断中的敏感性及特异性。结果不同类型四脑室区肿瘤中髓母细胞瘤平均Ki-67值最高,MK值与Ki-67存在明显正相关性,具有统计学意义(P0.01)。MK、Kr、Ka及MD值在鉴别髓母细胞瘤和室管膜瘤中均具有显著的统计学意义(P0.01),FA值则无统计学意义(P0.05)。在鉴别室管膜瘤和髓母细胞瘤时MK值的敏感性和特异性分别为88.89%和87.50%,ROC曲线下面积(AUC)为0.9722;MD值敏感性为77.78%,特异性87.50%,AUC为0.9028;FA值的敏感性及特异性最小,分别为66.67%和62.50%,AUC为0.6111。结论通过扩散峰值成像(DKI)可以更好的探定第四脑室肿瘤增殖状态,尤其MK值较其他参数值可以更好的反映肿瘤Ki-67的表达水平,且在鉴别诊断不同类型四脑室区肿瘤中具有重要意义。     

3.0T磁共振扩散张量成像对高级别脑胶质瘤和脑转移瘤的鉴别诊断价值

目的探讨3.0T磁共振扩散张量成像参数中的各向异性分数(FA)值、表观扩散系数(ADC)值对高级别脑胶质瘤和脑转移瘤的鉴别诊断价值。方法分析经手术病理或临床随访证实15例高级别脑胶质瘤和19例脑转移瘤,术前行常规MRI扫描、增强扫描、DWI及DTI扫描,选取感兴趣区(肿瘤囊变区、肿瘤实质区、肿瘤边缘区、瘤周水肿区、肿瘤周围正常脑实质区),分别测量其ADC值及FA值,比较两种肿瘤不同部位ADC值及FA值的差异,采用t检验。结果高级别脑胶质瘤与脑转移瘤的肿瘤实质区(t=4.09,P=0.001)、肿瘤边缘区(t=3.34,P=0.002)的FA值差异显著(P<0.05)。两种肿瘤周围水肿区(t=4.79,P=0.000)的ADC值差异显著(P<0.05)。结论扩散张量成像可以作为高级别脑胶质瘤和脑转移瘤的鉴别诊断方法。     

DCE-MRI在高级别脑胶质瘤与脑转移瘤中的鉴别诊断

目的 探讨动态对比增强磁共振成像(DCE-MRI)在鉴别高级别脑胶质瘤与脑转移瘤中的价值.方法 收集青岛大学附属医院经手术病理证实的高级别脑胶质瘤27例、脑转移瘤46例,所有患者术前均行颅脑增强MRI和DCE-MRI检查.利用血流动力学双室模型对各组数据进行定量分析,获取肿瘤实性成分及瘤周水肿区(瘤周1 cm内)的血流动力学参数[转运系数(Ktrans)、血管外细胞外间隙容积分数(Ve)、血管空间容积分数(Vp)],经统计学分析,比较各参数是否存在统计学差异.结果 高级别脑胶质瘤肿瘤实性成分与脑转移瘤肿瘤实性成分的Ktrans值、Ve值、Vp值差异均无统计学意义(P>0.05).高级别脑胶质瘤瘤周水肿区Ktrans值、Ve值明显高于脑转移瘤瘤周水肿区,差异有统计学意义(P<0.05),高级别脑胶质瘤瘤周水肿区Vp值略低于脑转移瘤水肿区,但差异无统计学意义(P>0.05).结论 DCE-MRI通过定量分析瘤周水肿区渗透参数,可以鉴别高级别脑胶质瘤与脑转移瘤.     

PWI鉴别诊断单发脑转移瘤和高级别胶质瘤的价值分析

目的探讨磁共振灌注加权成像(PWI)在单发脑转移瘤和高级别胶质瘤鉴别诊断中的价值。方法选择在本院治疗的255例单发脑转移瘤和104例高级别胶质瘤为研究对象(共359例,经病理组织活检确诊),术前均常规进行核磁共振扫描以及PWI检查,详细测量肿瘤区、瘤旁区、肿瘤周围水肿区(瘤周区)以及健侧无肿瘤的正常脑组织CBV(脑血容量)值,得出肿瘤区、瘤旁区、瘤周区相对无肿瘤的正常脑组织的rCBV(相对脑血容量)值,记录患者PWI特征。结果 255例单发脑转移瘤,104例高级别胶质瘤PWI显示:1)在肿瘤区,单发脑转移瘤的rCBV值(4. 85±2. 17),比高级别胶质瘤rCBV值(6. 32±2. 59)低,两者比较无统计学意义(P 0. 05),但均高于健侧正常脑组织的rCBV(2. 15±0. 42),差异具有统计学意义(P 0. 05); 2)转移瘤瘤旁区的rCBV值(1. 31±0. 25)低于高级别胶质瘤瘤旁区rCBV值是(3. 01±0. 56),差异具有统计学意义(P 0. 05); 3)在肿瘤周围水肿区内,单发脑转移瘤的rCBV值(1. 11±0. 31),比高级别胶质瘤的rCBV值低(1. 58±0. 29);差异均有统计学意义(P 0. 05); 4)单发转移瘤的PWI在对比剂首过后,信号恢复较高级别胶质瘤明显慢。结论对单发脑转移瘤与高级别胶质瘤采用PWI的检查手段,计算瘤周区的rCBV值,显示其血流灌注特性,有助于两者的鉴别诊断。     

MR扩散加权成像瘤周水肿区ADC值在脑肿瘤鉴别诊断中的价值

目的探讨MR扩散加权成像(DWI)瘤周水肿区表观扩散系数(ADC)值在脑内肿瘤鉴别诊断中的价值。资料与方法82例脑肿瘤患者进行常规MRI扫描和DWI检查,对照分析病变的实质部分、周围水肿区的ADC值、相对表观扩散系数(rADC)值、指数表观扩散系数(EADC)值、相对指数表观扩散系数(rEADC)值。结果高级别胶质瘤与低级别胶质瘤、转移瘤、脑膜瘤、淋巴瘤的瘤周水肿ADC值、rADC值差异有统计学意义(P<0.05)。高级别胶质瘤与低级别胶质瘤瘤周水肿的EADC值、rEADC值差异有统计学意义。结论瘤周水肿区ADC值有助于高级别胶质瘤与其他脑内肿瘤鉴别,也可有助于胶质瘤分级。     

急性脑损伤后继发性脑肿胀和脑水肿发生机制的实验研究

目的研究脑损伤后脑继发性损害中，脑肿胀和脑水肿的病理改变，探讨其相互关系。方法通过脑损伤动物模型，按时间顺序分成４个时相观察组（即６、２４、７２小时和７天），在光镜和电镜下观察脑损伤后不同时相的病理变化，同时测定脑含水量。结果发现脑肿胀在伤后６小时已出现、２４小时达高峰、以后逐渐下降，而脑水肿在伤后２４小时明显、７２小时达高峰、１周后开始下降。结论脑损伤后脑继发性损害是先出现脑肿胀而后出现脑水肿，而并非只出现脑水肿一种病理状态。     

Brain metastasis

Background and purpose

This study was performed to evaluate the prognostic role for survival of the number and the type of involved extracranial organs in patients with brain metastasis.

Material and methods

The data of 1146 patients who received whole-brain radiotherapy (WBRT) alone for brain metastasis have been retrospectively analyzed. In addition to the number of involved extra cranial organs, seven potential prognostic factors were investigated including WBRT regimen, age, gender, Karnofsky Performance Score (KPS), primary tumor type, number of brain metastases, and the interval from cancer diagnosis to WBRT. Additionally, subgroup analyses were performed for patients with involvement of one (lung vs. bone vs. liver vs. other metastasis) and two (lung + lymph nodes vs. lung + bone vs. lung + liver vs. liver + bone vs. other combinations) extracranial organs.

Results

The 6-month survival rates for the involvement of 0, 1, 2, 3, and ≥?4 extracranial organs were 51, 30, 16, 13, and 10?%, respectively (p?<?0.001). On multivariate analysis, the number of involved extracranial organs maintained significance (risk ratio 1.26; 95?% confidence interval 1.18–1.34; p?<?0.001). According to the multivariate analysis, age (p?<?0.001), gender (p?=?0.002), and KPS (p?<?0.001) were also independent prognostic factors for survival. In the subgroup analyses of patients with involvement of one and two extracranial organs, survival was not significantly different based on the extracranial organ involved.

Conclusion

The number of involved extracranial organs proved to be an independent prognostic factor in patients with brain metastasis, regardless of the organs involved. The number of involved extracranial organs should be considered in future trials designed for patients with brain metastasis.     

Linac Radiosurgery Versus Whole Brain Radiotherapy for Brain Metastases

BACKGROUND AND PURPOSE: For patients with inoperable brain metastases, whole brain radiotherapy (WBRT) has been the standard treatment for decades. Radiosurgery is an effective alternative strategy, but has failed to show a substantial survival benefit so far. The prognostic factors derived from the RTOG recursive partitioning analysis (RPA) provide a framework that allows a nonrandomized comparison of the two modalities. PATIENTS AND METHODS: From 1991 to 1998, 117 patients with one to three previously untreated cerebral metastases underwent single-dose linac radiosurgery (median dose 20 Gy) without adjuvant WBRT. After radiosurgery, 26/117 patients (22%) had salvage WBRT, radiosurgery or neurosurgical resection of recurrent (4/117) and/or new (24/117) metastases. Survival of these patients was compared to a historical group of 138 patients with one to three lesions treated by WBRT (30-36 Gy/3-Gy fractions) from 1978 to 1991; only nine of these patients (7%) had salvage WBRT. All patients were classified into the three RPA prognostic classes based on age, performance score, and presence of extracranial tumor manifestations. RESULTS: In RPA class I (Karnofsky performance score > or = 70, primary tumor controlled, no other metastases, age < 65 years), radiosurgery resulted in a median survival of 25.4 months (n = 23, confidence interval [CI] 5.8-45.0) which was significantly longer than for WBRT (n = 9, 4.7 months, CI 3.8-5.5; p < 0.0001). In RPA class III (Karnofsky performance score < 70), no significant difference in survival between radiosurgery (n = 20, 4.2 months, CI 3.2-5.3) and WBRT (n = 68, 2.5 months, CI 2.2-2.8) was found. In RPA class II (all other patients), radiosurgery produced a small, but significant survival advantage (radiosurgery: n = 74, 5.9 months, CI 3.2-8.5, WBRT: n = 61, 4.1 months, CI 3.4-4.9; p < 0.04). CONCLUSION: Radiosurgery in patients with one to three cerebral metastases results in a substantial survival benefit only in younger patients with a low systemic tumor burden when compared to WBRT alone. It cannot be excluded that this effect is partially caused by the available salvage options after radiosurgery.     

Prognostic Factors for Brain Metastases after Whole Brain Radiotherapy

PURPOSE: Prognostic factors for overall survival of patients treated for brain metastases with whole brain radiotherapy (WBRT) at a single institution were retrospectively evaluated, and the validity of the RTOG recursive partitioning analysis (RPA) for prognostic classes was assessed. PATIENTS AND METHODS: The data of all patients (n = 268) with brain metastases from solid tumors homogeneously treated between 01/1997 and 09/1999 at the University of Heidelberg, Germany, with WBRT without surgery or radiosurgery were reviewed. 13 different patient- and therapy-related variables were evaluated for prognosis. Second, a grouping of the study cohort was performed according to the RTOG RPA prognostic classes. RESULTS: Median survival of the whole population after the start of WBRT was 3.8 months. The 1-year survival rate was 19%. Multivariate analysis revealed that only the Karnofsky performance status, control of the primary and no extracranial disease were independent prognostic factors for overall survival. These are also the main determinants of the RTOG RPA classes. Applying the RTOG RPA classes to the authors' data set revealed three subgroups with significantly different prognosis. CONCLUSION: Based on this analysis, prognostic factors for survival after WBRT in patients with brain metastases could be identified. A total of 19% (n = 44/232) survived > or = 1 year, whereas overall survival was poor. The potential value of the RPA classes in estimating the patient's prognosis could be confirmed.     

颅脑磁共振血管造影

目的：研究MRA的诊断价值。材料和方法：在0．5T超导磁共振成像机（VectraⅡ，GE）上，采用时间飞越法（TOF）和相位对比法（PC）作磁共振血管造影（MRA）。本文回顾分析了88例颅脑MRA的表现，68例采用PC法；5例采用TOF法；15例两者均采用。其中5例患者MRA检查后立即又做了DSA检查。结果：MRA可用于诊断各种颅内动脉瘤、血管畸形、血管狭窄或闭塞性病变，可以大致观察颅内肿瘤的血供及正常血管的移位或受侵情况。结论：本文比较了PC法和TOF法的优缺点，认为前者更能清晰完整显示颅内血管及其病变，MRA对于诊断各种血管性病变极有价值。