3.0 T多体素1H-MRS在脑胶质瘤与单发脑转移瘤鉴别诊断中的应用分析

目的 探索3.0 T多体素氢质子磁共振波谱成像（¹H-MRS）在脑胶质瘤、单发脑转移瘤鉴别诊断中的应用价值。方法 脑胶质瘤20例、单发脑转移瘤11例纳入研究,均术前行¹H-MRS检查。分析脑胶质瘤与单发脑转移瘤瘤体区、瘤周水肿区的胆碱（Cho）/N-乙酰天门冬氨酸（NAA）、Cho/肌酸（Cr）、NAA/Cr值的统计学差异,并用受试者工作特征（ROC）曲线分析各指标鉴别脑胶质瘤与单发脑转移瘤的效能。结果 脑胶质瘤组与单发脑转移瘤组间瘤体区Cho/Cr、NAA/Cr及瘤周水肿区Cho/NAA、NAA/Cr值差异均有统计学意义（P<0.05）;瘤体区NAA/Cr的ROC曲线下面积（AUC）最大（AUC=0.74）,当瘤体区NAA/Cr为1.17时,鉴别脑胶质瘤与单发脑转移瘤的敏感度为55.30%,特异度为82.40%。结论 常规MRI结合¹H-MRS能提高脑胶质瘤与单发脑转移瘤鉴别诊断的准确性,且瘤体区NAA/Cr值鉴别效能最优。     

磁共振DTI和多体素~1H-MRS在胶质瘤术前分级中的联合应用

目的探讨MR弥散张量成像(DTI)和多体素氢质子MR波谱(~1H-MRS)在胶质瘤术前分级诊断中的临床联合应用价值。方法回顾分析我院经病理证实的38例胶质瘤术前常规MR、DTI和~1H-MRS资料,其中低级别胶质瘤(LGG,WHO Ⅱ级)15例,高级别胶质瘤(HGG,WHO Ⅲ~Ⅳ级)23例。以肿瘤周围脑实质为种子点重建弥散张量纤维束成像(DTT)图。测量肿瘤实质区(TT)、瘤周区(AT)以及对侧正常脑组织区(CT)的各项异性指数(FA)、平均弥散系数(MD)和胆碱(Cho)/肌酸(Cr)、Cho/N-乙酰天冬氨酸(NAA)、NAA/Cr值。比较组内同一参数在不同组织间差异,并比较各参数值在两组间的差异。结果 DTT显示HGG的TT和AT区白质纤维束以破坏为主(19/23,82.6%),LGG以浸润为主(13/15,86.7%)。HGG组由TT、AT至CT区FA、MD、NAA/Cr逐渐增高,Cho/Cr、Cho/NAA逐渐降低(P0.05)。LGG组TT区FA、MD、NAA/Cr低于AT和CT区,Cho/Cr、Cho/NAA相反(P0.05)。HGG组TT和AT区MD、NAA/Cr均低于LGG组,Cho/Cr、Cho/NAA均高于LGG组(P0.05)。HGG组FA值仅在AT区低于LGG组(P0.05)。结论临床可联合应用DTI和多体素~1H-MRS各参数对胶质瘤术后进行分级诊断,从而有助于及时合理的选择个体化治疗方案。     

探讨联合应用MRS和DWI在脑胶质瘤分级中的诊断价值

目的 探讨联合应用氢质子磁共振波谱(1H-MRS)相关代谢物和磁共振扩散加权成像(DWI)的表观扩散系数(ADC)值在脑胶质瘤分级诊断中的诊断价值.方法 回顾性分析经病理证实的59例脑胶质瘤的MRS和DWI图像.按照WH0 2007标准,将病例分为两组:低级别胶质瘤组(Ⅰ～Ⅱ级,24例)和高级别胶质瘤组(Ⅲ～Ⅳ级,35例),测量并计算肿瘤实质区、健侧脑组织区代谢物及ADC值的相对值和比值,作统计学分析.结果 在59例脑胶质瘤中,rNAA、Cho/Cr、NAA/Cr、NAA/Cho及rADC在低、高级别组胶质瘤比较中差异均有统计学意义(P＜0.05),而rCho和rCr在两组胶质瘤比较中差异无统计学意义(P＞0.05);经受试者工作特征曲线分析发现rNAA、NAA/Cr、NAA/Cho、rADC鉴别胶质瘤分级的曲线下面积＞0.5,MRS+ rADC鉴别胶质瘤分级的曲线下面积(0.956)＞单独运用MRS(0.893)或rADC的曲线下面积(0.805),MRS+ rADC诊断低、高级别胶质瘤的敏感性和特异性分别达88.6％、95.8％.结论 联合分析MRS参数(rNAA、NAA/Cr、NAA/Cho)和DWI参数(rADC)对诊断胶质瘤分级具有较高的敏感性和特异性,可为临床治疗方案的制定及判断预后提供帮助.     

MR弥散、灌注、波谱成像在单发脑转移瘤与恶性胶质瘤鉴别诊断中的价值

目的探讨磁共振弥散加权成像(DWI)、灌注加权成像(PWI)和1H波谱(1H-MRS)检查在单发脑转移瘤与恶性胶质瘤鉴别诊断中的应用价值。方法对术前进行了磁共振DWI、PWI和MRS检查并经病理证实的18例单发脑转移瘤和16例恶性胶质瘤进行回顾性分析,测量各病灶瘤体区、瘤周区及对照区的ADC、rCBV及Cho/Cr、Cho/NAA、NAA/Cr值,并计算rADC及rrCBV。结果瘤灶区rADCT单发脑转移瘤与恶性胶质瘤之间没有统计学差异(P>0.05),瘤周区rADCP脑转移瘤高于恶性胶质瘤,分别为1.98±0.69及1.43±0.31(P<0.05);瘤灶区rrCBVT和瘤周区rrCBVP转移瘤均低于恶性胶质瘤,分别为1.07±0.62、2.68±1.22(P<0.05)和0.38±0.23、1.11±0.61(P<0.05);瘤灶区Cho/Cr、Cho/NAA、NAA/Cr值脑转移瘤与恶性胶质瘤之间差异均无统计学意义;瘤周区胶质瘤Cho峰高于脑转移瘤,Cho/Cr和Cho/NAA值均高于脑转移瘤,分别为2.25±0.75、1.91±0.40和1.31±0.15、0.96±0.32(P<0.05和P<0.0...     

脑胶质瘤ADC值及1H磁共振波谱分析与病理分级的相关性研究

目的 探讨磁共振扩散加权成像(DWI)的表观弥散系数(ADC)值和1H磁共振波谱(MRS)对脑胶质瘤的诊断价值.方法 对43例病理证实的胶质瘤患者进行MRI平扫、增强、DWI和1H磁共振波谱成像,分别测量肿瘤的实质部分、肿瘤坏死囊变区、肿瘤周边区域及对侧相应部位正常脑白质的ADC值和相对ADC值,同时测量脑胶质瘤中的各种化学成分,如NAA、Cho 、Cr 和Lac等,并计算NAA/Cho、NAA/Cr、NAA/Lac、Cho/Cr、Lac/Cr比值,测量结果与术后病理分级进行对照.结果 ①低级胶质瘤(1~2级)组的肿瘤实质部分的平均ADC值和rADC值均明显高于高级胶质瘤(3~4级)组(P<0.01).②胶质瘤实质部分的ADC值和rADC值均与肿瘤组织的病理分级呈明显负相关(P值均<0.01,r= - 0.767和-0.792).③ 高级别、低级别脑胶质瘤的肿瘤组织NAA/Cho、NAA/Cr、Cho/Cr比值存在显著性差异(P<0.01);高、低级别脑胶质瘤的肿瘤组织分别与对侧正常脑组织NAA/Cho、NAA/Cr、Cho/Cr比值存在显著性差异(P<0.01).④ 脑胶质瘤的NAA/Cho、NAA/Cr比值与病理级别呈负相关,r分别为-0.782和-0.712;Cho/Cr比值与病理级别呈正相关,r=0.806.结论 ADC值和1H MRS与胶质瘤的病理分级有明显相关性,可作为胶质瘤术前评价的依据.     

MR多参数评分鉴别脑胶质瘤术后复发与放射性脑损伤的初步研究

目的 探讨MR多参数评分系统对脑胶质瘤术后复发与放射性脑损伤的诊断价值.资料与方法 对18例脑胶质瘤术后出现异常强化区患者进行扩散加权成像(DWI)、氢质子磁共振波谱(1H-MRS)检查.计算感兴趣区的表观扩散系数比值(rADC)和代谢物峰值比值[胆碱/肌酸(Cho/Cr)、胆碱/氮-乙酰天门冬氨酸(Cho/NAA)].根据受试者工作特征(ROC)曲线确定各比值参数的最佳诊断阈值,并对每个病灶分别进行评分,联合多个参数(rADC、Cho/Cr、Cho/NAA)评分结果建立多参数评分系统,对每个病灶综合评分,总得分≥12者诊断为复发,总得分<2者诊断为放射性脑损伤.通过Kappa检验分析各参数诊断结果与金标准诊断结果的吻合程度.结果 最佳诊断阈值分别为:1.41(rADC)、1.31(Cho/Cr)和1.43(Cho/NAA),诊断准确性、敏感性、特异性分别为:83.3%、83.3%、83.3%(rADC),83.3%、91.7%、66.7%(Cho/Cr),83.3%、83.3%、83.3%(Cho/NAA),多参数评分系统(94.4%、91.7%、100%);诊断结果与金标准吻合程度分别为:rADC(高度,K=0.64)、Cho/NAA(高度,k=0.64)、Cho/Cr(高度,K=0.61)、多参数评分系统(极强,K=0.87).结论 与MR单个参数诊断结果相比,MR多参数评分系统可明显提高对胶质瘤术后复发与放射性脑损伤的诊断准确性.     

3．0T磁共振多体素^1H-MRS和DWI对常见脑肿瘤特征分析的价值

目的：探讨3．0T磁共振多体素^1H-MRS及DWI在常见颅内肿瘤特征分析的价值。方法：脑肿瘤患者30例,多体素^1H-MRS感兴趣区包括肿瘤实质区、瘤周水肿区及正常参照区。计算上述各区域的NAA、Cho、Cr等多种代谢物的值;DWI测量肿瘤不同部位信号值,计算ADC值。结果：胶质瘤、转移瘤、脑膜瘤三者之间肿瘤实质区的NAA／Cho、NAA／Cr和Cho／Cr平均值与参照区比较有显著性差异（P〈0．05）;高、低级别胶质瘤间瘤周水肿区的NAA／Cho和Cho／Cr具有统计学差异（P〈0．05）,高级别胶质瘤与转移瘤间瘤周水肿区的NAA／Cho、NAA／Cr和Cho／Cr均有统计学差异（P〈0．05）。DWI示高、低级别胶质瘤间肿瘤实质区及瘤周水肿区的ADC值均有显著性差异（P〈0．05）;高级别胶质瘤与转移瘤间瘤周水肿区的ADC值有统计学差异（P〈0．05）。结论：多体素^1H-MRS与DWI相结合有助于脑肿瘤的特征分析、胶质瘤恶性程度分级、确定病灶浸润范围等。     

1H-MRS在原发性中枢神经系统淋巴瘤与高级别胶质瘤鉴别诊断中的价值

目的 探讨单体素不同回波时间(TE =30 ms/135 ms)和多体素长回波(TE=135 ms) MRS在原发性神经系统淋巴瘤(PCNSL)与高级别胶质瘤(HGG)鉴别诊断中的价值.方法 回顾性分析19例PCNSL(13例经病理证实,6例经诊断性治疗确诊)和22例HGG(均经病理证实)患者影像资料.19例PCNSL均行单体素短和长回波MRS检查,其中15例行多体素长回波MRS检查.22例HGG均行单体素短和长回波MRS及多体素长回波MRS检查.分析不同TE时间单体素MRS在瘤体中的不同代谢物相对比值,同时分析多体素长回波MRS在瘤体及瘤周中的不同代谢物相对比值.结果 单体素短回波MRS的Cho/Cr和NAA/Cr在PCNSL与HGG的鉴别诊断中差异均有统计学意义(P＜0.05);Cho/NAA和(Lac+ Lip)/Cr在两者的鉴别诊断中差异均无统计学意义(P＞0.05).单体素长回波MRS的Cho/Cr、NAA/Cr和Cho/NAA在两者的鉴别诊断中差异均有统计学意义(P＜0.05).多体素长回波MRS瘤体的Cho/Cr、NAA/Cr和Cho/NAA在两者的鉴别诊断中差异均无统计学意义(P＞0.05);瘤周的Cho/Cr、NAA/Cr和Cho/NAA在两者的鉴别诊断中差异均无统计学意义(P＞0.05).结论 单体素MRS代谢物是鉴别诊断PCNSL与HGG的有效指标,多体素长回波MRS鉴别诊断价值有限.     

亚急性期1H-MRS及DTI对中重度缺氧缺血性脑病新生儿预后评估的价值

目的 利用氢质子磁共振波谱成像（¹H-MRS）和扩散张量成像（DTI）技术,探讨亚急性期¹H-MRS代谢物比值和部分各向异性分数（FA）值对中重度缺氧缺血性脑病（HIE）足月新生儿预后评估的价值。方法 搜集37例亚急性期中重度足月HIE患儿,分别选用TE 135 ms和TE 35 ms行头颅¹H-MRS三维多体素扫描及DTI检查,根据其12～18个月Gesell量表发育商（DQ）分为预后良好组（n=21）和预后不良组（n=16）,比较两组间豆状核区N-乙酰天门冬氨酸（NAA）/肌酐（Cr）、胆碱（Cho）/Cr、NAA/Cho、乳酸（Lac）/Cr、Lac/NAA、Lac/Cho比值及各深部白质FA值的差异,应用受试者工作特征曲线（ROC）分析各指标预测HIE预后的价值,并与DQ进行相关性分析。结果 内囊后肢、胼胝体压部及大脑脚FA值在预后不良组和预后良好组间存在显著性差异（P<0.05）,且内囊后肢FA值预测HIE预后的效能最高;TE 135 ms NAA/Cho和TE 35 ms Lac/NAA在两组间存在统计...     

多体素1H-MRS在脑胶质瘤与脑脓肿鉴别诊断中的应用

目的 评价多体素MRS在脑胶质瘤与脑脓肿诊断和鉴别诊断中的应用价值.方法 收集16例脑内占位病例,10例胶质瘤(Ⅲ~Ⅳ级7例,Ⅱ级3例,按照WHO分级标准,均经手术病理证实)、6例脑炎脑脓肿(均经手术病理或穿刺活检证实),所有患者均行MRI常规检查和多体素MRS检查.测量病灶区及对侧正常区的Cho、Cho/NAA,并计算Cho-norm(标准化Cho:病灶区Cho/正常对侧区Cho).结果 10例胶质瘤瘤体Cho/NAA高于对侧正常区,差异有统计学意义;6例脑炎脑脓肿病灶Cho/NAA高于对侧正常区,差异有统计学意义;胶质瘤瘤体Cho/NAA高于脑炎脑脓肿病灶区,然而P＞0.05,差异无统计学意义;胶质瘤瘤体Cho-norm高于脑炎脑脓肿病灶区,差异有统计学意义.结论 多体素MRS中Cho-norm能够帮助鉴别脑胶质瘤及脑炎脑脓肿,从而制订最佳治疗方案.     

细胞自噬与肿瘤发生发展

自噬是真核生物中一种高度保守的胞内降解途径.其主要通过溶酶体或液泡进行饥饿状态下的营养动员,清除受损蛋白质、细胞器和胞内病原体.自噬主要包括巨自噬、分子伴侣介导自噬(CMA)和微自噬.自噬已被证实与多种人类疾病相关,其在肿瘤发生发展中具有重要意义.近年研究中,对于自噬和肿瘤关系有了进一步的认识,该文就自噬分子机制、调控...     

Physiologic and pathologic calcifications and ossifications in the face and neck

The aim was to give a systematic presentation of physiologic and pathologic calcifications and ossifications in the face and neck with a special emphasis on clinical relevance. In a sometimes subacute setting one should recognize specific calcifications which often lead to important diagnoses such as fungal sinusitis or sclerosing labyrinthitis. In a more chronic situation intraocular calcifications in small children are pathognomonic for retinoblastoma. Juxtatumoral sclerosis of the laryngeal cartilage in laryngopharyngeal carcinoma is usually caused by tumor infiltration of the cartilage resulting in a higher tumor stage and, this way, has a major impact on the therapeutical strategy. Calcified lymph nodes are mainly unspecific but can be the result of tuberculosis or metastases of thyroid cancer. Cross-sectional imaging methods, most of all computed tomography, are ideally suited to reveal head and neck calcifications and ossifications, especially those which are clinically relevant.     

Head and neck infection and inflammation

This article discusses the imaging manifestations of infectious and inflammatory conditions of the head and neck. Special attention is paid to the sites, routes of spread, and complications of neck infections. Because the clinical signs and symptoms and the complications of these conditions are often determined by the precise anatomic site involved, anatomic considerations are stressed. Familiarity with the fascial layers, spaces of the neck, and the contents of each space is helpful for this discussion. The fascial layers of the neck are important barriers to infection, and once infection is established, the fascial layers play a part in directing its spread.     

Staging and surgical management of pancreatic and biliary cancer and inflammation

Management of benign and malignant diseases of the pancreas, liver, and biliary tract has made remarkable progress in the last two decades. Advances in minimally invasive surgery, interventional radiology, and diagnostic and therapeutic endoscopy have changed the treatment of common diseases such as cholelithiasis and more serious diseases such as pancreatic adenocarcinoma. Advances in biliary tract and pancreatic surgery have paralleled the advances in ultrasonographic imaging, CT, and MR imaging. This article outlines the surgeon's perspective on radiologic imaging and preoperative staging of benign and malignant biliary and pancreatic disease.     

The thyroid and parathyroid glands. CT and MR imaging and correlation with pathology and clinical findings

Thyroid imaging approach is based on the preliminary clinical evaluation. Lesions that are smaller than 2 cm should be assessed with US, which is capable of discriminating masses as small as 2 mm and distinguishing solid from cystic nodules. US-guided FNAB provides tissue for cytologic examination of thyroid nodules. CT and MR imaging are indicated for larger tumors (greater than 3 cm diameter) that extend outside the gland to adjoining structures, including the mediastinum, and retropharyngeal region. Metastatic lymph nodes in the neck and invasion of the aerodigestive tract are also in the realm of CT and MR imaging. Thyroid nodules are categorized on scintigraphy as hot or cold nodules. Hot nodules are rarely malignant, whereas cold nodules have an incidence of 10% to 20% of malignancy. Calcifications (amorphous, globular, nodular, and linear) occur in adenomas and carcinomas and have no differential diagnostic features except for psammomatous calcifications, which are a pathognomonic finding in papillary carcinomas and a small percentage of medullary carcinomas. Papillary carcinoma is the most common malignant tumor (80%) followed by follicular (20% to 25%); medullary (5%); undifferentiated; anaplastic carcinomas (< 5%); lymphoma (5%); and metastases. Lymph node metastases are common in papillary carcinoma, 50% at presentation, and less common in follicular carcinomas. The metastatic nodes in papillary carcinoma may enhance markedly (hypervascular); show increased signal intensity on T1-weighted images (increased thyroglobulin content or hemorrhage); and reveal punctate calcifications. Localized invasion of the larynx, trachea, and esophagus occurs predominantly in papillary and follicular carcinomas; the incidence is less than 5%. Ectopic thyroid tissue may be encountered in the tongue (foramen cecum); along the midline between posterior tongue and isthmus of thyroid gland; lateral neck; mediastinum; and oral cavity. Goiter and malignant tumors, notably papillary carcinoma, may develop in ectopic thyroid tissue. Carcinomas may also arise in thyroglossal duct cysts, which develop from duct remnants between the foramen cecum and thyroid isthmus. Infectious disease of the thyroid gland is not common and the CT and MR imaging findings are similar as described under neck infection. Other types of inflammatory disorders including Hashimoto's thyroiditis, granulomatous thyroiditis, and Riedel's struma display no specific imaging features. Imaging studies may, however, be indicated to confirm a suspected clinical diagnosis and assess compromise of the airway (Riedel's struma). HPT is a clinical diagnosis in which hypercalcemia is the most important finding. Parathyroid hyperplasia, adenoma, and carcinoma represent underlying lesions. To relieve the patient's symptoms surgical extirpation is indicated. The surgical success rate without imaging is 95%. The indications for imaging studies vary but it is generally agreed that reoperation after a previous failed surgical attempt and suspicion of an ectopic parathyroid adenoma should be investigated by imaging. These consist of US, nuclear medicine studies, CT and MR imaging. US and technetium sestamibi scanning have the highest accuracy rate for localizing an adenomatous gland at and near the thyroid gland. Ectopic adenomas, particularly if they are located in the mediastinum, are preferrably investigated with CT and MR imaging with gadolinium and fat suppression. Carcinomas and parathyroid cysts are optimally evaluated by CT and MR imaging. On MR imaging adenomas are low in signal intensity on T1-weighted images, high in signal intensity on T2-weighted images, and enhance post introduction of gadolinium.