脑胶质瘤的MRI诊断及鉴别诊断

目的研究磁共振成像(MRI)对脑胶质瘤的诊断、鉴别价值和意义。方法选取脑胶质瘤患者21例,接受MRI扫描和氢质子磁共振波谱(H-MRS)检查。结果脑胶质瘤MRI表现主要是病变区域呈现弥漫性斑片状,且T1WI上主要表现低信号和等信号,而T2WI和T2FLAIR则是均匀高信号。根据MRI扫面诊断结果及世界卫生组织(WHO)对于脑肿瘤的分类标准进行病理类型分类,其中以间变性星形细胞瘤最多(42. 86%);胶质瘤主要分布在额叶(38. 10%)。少量出血患者MRI瘤体征象和出血征象并存,而大量出血者MRI则主要表现为出血征象。H-MRS分析显示,瘤体区、瘤周区及正常对照区主要代谢物比值差异有统计学意义(P0. 05)。N-乙酰天门冬氨酸(NAA)/胆碱(Cho)和NAA/肌酸(Cr)瘤体区明显低于正常对照区和瘤周区,而瘤体区Cho/Cr值明显高于正常对照区和瘤周区(P0. 05)。结论 MRI可以有效对脑胶质瘤进行诊断,并且结合H-MRS分析能够进一步提高脑胶质的诊断成功率。     

中枢神经细胞瘤的MRI及病理表现(附19例分析)

目的探讨中枢神经细胞瘤(CNC)的MRI及病理表现特点,提高诊断准确率。方法回顾性分析19例经手术病理证实的CNC患者的MRI表现及病理特点。结果 MRI检查显示肿瘤位于侧脑室体部前2/3区域15例、第四脑室2例、小脑蚓部及左侧额叶各1例,肿瘤边界清楚或不清楚,5例肿瘤与丘脑或侧脑室壁粘连,T1WI呈等信号或稍低信号、T2WI呈等信号或稍高信号,17例病灶出现囊变区、14例肿瘤周边或内部可见供血血管(多位于肿瘤底部),增强后3例病灶明显均匀强化、12例明显不均匀强化、4例轻中度不均匀强化;免疫组织化学染色检查显示N-乙酰神经氨酸(NeuN)及突触蛋白(Syn)均呈阳性。结论 CNC的MRI表现具有特征性,免疫组织化学染色检查对其诊断有较高的特异性。     

节细胞神经瘤的CT、MRI影像特征分析

目的探讨节细胞神经瘤（GN）的CT、MRI影像学特点。方法回顾性分析14例经手术病理证实的GN患者的CT、MRI影像资料。结果本组中11例行CT扫描,其中7例行增强扫描;6例行MRI平扫及增强扫描。CT平扫9例病灶密度均匀,2例密度欠均匀,3例可见少许小点状钙化灶;增强扫描动脉期1例无明显强化,6例轻度强化,2例静脉期可见渐进性强化。MRI平扫T1WI病灶呈较均匀等或低信号,T2WI呈明显不均匀高信号,3例可见漩涡状征象;增强扫描1例轻度强化,2例无强化,2例明显强化。结论GN的CT影像特点是密度较低的实性肿块,瘤内散在点状及沙粒样钙化,病灶呈渐进性强化;MRI影像学特点是T1WI呈均匀或稍不均匀的等低信号,T2WI呈不均匀的等高信号,还可发现旋涡状征像。     

MRI在肝腺瘤诊断中的应用

目的探讨MRI对肝腺瘤的诊断价值。方法回顾性分析10例肝腺瘤患者的MRI表现。结果病理证实肝腺瘤10例,其中MRI诊断为肝腺瘤5例。7例单发,直径为(5.2±1.9)cm;3例多发,最大病灶直径为(9.0±3.0)cm。8例T1WI序列和T2WI序列呈长T1和长(稍长)T2信号,1例呈长T1稍短T2信号,1例呈短T1等T2信号;9例回波序列见大量脂质成分。增强扫描时,7例动脉期病灶明显强化,门脉期及延迟期造影剂消退,病灶为等信号或稍高信号;2例动脉期轻度不均匀强化;1例动脉期病灶增强与肝实质近似,门脉期和延迟期造影剂较前消退。肝腺瘤呈现"快进慢出"信号特征;8例门脉期及延迟期病灶周围可见环形强化假包膜。结论肝腺瘤的增强MRI有特征性表现,有助于与其他肝内肿瘤鉴别,但明确诊断仍须要病理支持。     

磁共振成像在甲状旁腺腺瘤诊断中的应用

目的探讨甲状旁腺腺瘤的MRI表现特点。方法40例经手术病理证实的病例进行MRI平扫及增强扫描。结果肿瘤常见于颈下部气管食管隐窝区,颈动脉鞘内侧,也可位于上纵隔; 呈卵圆型,有完整的包膜。可出现坏死、液化及囊性变; MRI表现T1WI呈等、等高及等低信号,T2WI上呈高信号,坏死、囊变区信号明显增高,增强扫描后肿瘤明显强化。结论MRI具有较高的软组织分辨能力及三维、多参数成像功能,对甲状旁腺腺瘤的诊断更具优越性、敏感性和准确性。     

3.0 T TX磁共振成像对DMBA诱导大鼠胰腺病损的诊断价值

目的 探讨3.0 T TX磁共振成像(MRI)对7,12-二甲基苯并蒽(DMBA)诱导的大鼠胰腺病损的诊断价值。方法 将DMBA 2 mg/100 g植入60只雄性SD大鼠胰腺,术后2、4、6个月对存活的55只行腹部MRI(3.0 T TX)冠状位、横断位平扫及增强扫描,并与术前10只正常大鼠的MRI比较,随后取胰腺组织行病理检查。结果术后2个月,MRI显示大鼠均出现胰腺形态不规则、腹水、肠管扩张现象;19只行病理检查呈现急、慢性胰腺炎改变。术后4个月,MRI显示33.3%(6/18)的大鼠出现胰腺囊肿,病理检查为胰腺假性囊肿,直径0.3~1.0 cm。术后6个月,38.9%(7/18)的大鼠出现胰腺假性囊肿,MRI表现为较长T1、长T2信号,结节中心低信号,增强扫描后不明显。1只可见胰腺部位肿瘤,直径约0.3 cm;MRI特点为稍长T1、长T2信号,病变信号不均匀,中心呈更长T1信号,增强扫描后病变边缘可见较明显强化,病变内部无明显强化;病理及免疫组化诊断为胰腺平滑肌肉瘤。结论使用3.0 T TX MRI可发现DMBA诱导的大鼠胰腺病损,可分辨直径≤0.5 cm的胰腺部囊肿及肿瘤。     

儿童小脑毛细胞型星形细胞瘤的MRI诊断

回顾性分析28例儿童小脑毛细胞型星形细胞瘤患儿的临床资料,研究其T1加权、T2加权、液体衰减反转恢复成像(FLAIR)和增强后的MRI表现.发现病灶在小脑蚓部19例、小脑半球9例.MRI表现:囊性伴壁结节型15例,假囊性或伴壁结节型9例,实质型4例.肿瘤的活性部分于FLAIR和T2加权呈高信号,增强后明显强化.T1加权肿瘤囊性部分呈均匀低信号,肿瘤壁结节呈稍低信号或等信号.认为MRI诊断对小脑毛细胞型星形细胞瘤具有较高的准确性,尤其是增强扫描对定性诊断及鉴别诊断具有重要的价值.     

肝脏神经内分泌癌的CT及MRI特征

目的探讨肝脏神经内分泌癌(HNEC)的CT及MRI特征,以期提高其诊断水平。方法回顾性分析经病理免疫组织化学证实的37例HNEC患者的影像资料,分析其表现特点。结果原发性HNEC常为单发,CT表现肿瘤平扫为低密度或混杂低密度占位,肿瘤合并出血时其内见斑片状稍高密度,增强扫描呈渐进性强化,肿瘤实性部分门脉及平衡期CT值略高于动脉期;磁共振DWI多呈均匀或厚壁样稍高信号,T2WI呈稍高信号,部分病变内见高信号囊变区,T1WI呈稍低信号,部分病变呈稍高信号,增强扫描呈中度均匀强化或边缘强化,部分病变内可见粗大供血动脉,门脉及延迟期呈等或稍低信号,部分病变可见完整或不完整假包膜,肿瘤周围门脉及肝静脉受压移位,但无癌栓形成。转移性HNEC常为多发、体积较大,CT平扫呈稍低或低密度,增强扫描动脉期病变多呈边缘轻中度强化或不均匀强化,门脉及平衡期相对肝实质呈等或稍低密度;磁共振检查DWI多呈环形高信号,T2WI呈稍高信号, T1WI呈稍低信号,大部分病变内见囊变坏死区,增强扫描动脉期不均匀强化或环形强化,门脉及延迟期多数可见偏心靶环征,部分门脉血管内可见癌栓。结论 HNEC可分为原发性和转移性,其影像学表现具有一定的特征性,结合临床资料及免疫组织化学有助于病变的诊断。     

恶性周围神经鞘膜瘤17例MSCT及MRI表现与病理对照分析

目的：分析恶性周围神经鞘膜瘤（ MPNST）的MSCT、MRI及病理学表现,以提高诊断准确性。方法收集17例经手术病理证实的MPNST,将其MSCT、MRI表现并与病理进行对照分析。结果17例中,上肢4例,下肢4例,颈背部3例,骶髂关节区3例,椎管内2例,食管1例。肿瘤巨大,瘤内坏死出血常见,钙化较少。 MSCT平扫多为等、低混杂密度影,MRI平扫T1 WI多呈等、略低信号,T2 WI及STIR序列多呈高、低混杂信号,增强扫描瘤体多呈边缘环形明显强化,瘤内实性部分结节状、斑索状不均匀明显强化。病理：肿瘤多呈球形或纺锤形,有假包膜,与神经干粘连,瘤内常坏死、出血,可囊变,钙化少见。镜下肿瘤细胞多形性,以梭形细胞为主;NSE、S-100、CD56、Vimentin标记物多呈阳性。结论恶性周围神经鞘膜瘤多位于较大神经干走行区。 CT、MRI表现与病理成分有较强相关性,结合二者有助于提高诊断与鉴别诊断水平。     

鞍旁海绵状血管瘤的MRI诊断价值

目的分析经手术和病理证实的蝶鞍旁海绵状血管瘤MRI影像表现,探讨其诊断和鉴别诊断。方法 5例均经手术、病理证实,均行MR平扫和增强扫描,4例行MR扩散加权成像(DWI),1例行1HMRS单体素检查。结果蝶鞍旁海绵状血管瘤体积大小不一,可同时伸入到鞍内。MR-T1 WI呈等或稍低于脑灰质信号,T2 WI呈类似脑脊液高信号。增强扫描病变呈非常显著强化,可不均匀。DWI呈等或稍低信号,但表观扩散系数(ADC)值明显高于正常脑实质。1HMRS表现为NAA峰、Cr峰和Cho峰消失,可出现Lip峰。结论蝶鞍旁海绵状血管瘤MRI平扫鉴别诊断困难,信号与脑脊液容易较近,特别小的海绵状血管瘤易漏诊;增强扫描非常显著强化,ADC值明显升高而DWI接近等信号,1HMRS检查无NAA峰、Cr峰和Cho峰,MRI检查可以对蝶鞍旁海绵状血管瘤作出定性、定位诊断。     

胼胝体梗死的临床与影像学分析

目的 探讨胼胝体梗死患者的临床和影像学特点.方法 收集符合脑梗死诊断的416例患者的临床资料,其中8例经过MRI证实为胼胝体梗死.结果 胼胝体梗死占全部脑梗死患者的1.9%.7例CT扫描未显示胼胝体梗死,经非增强MRI检查显示病灶,另1例经增强MRI检查显示病灶.梗死灶可仅累及胼胝体(膝部、体部或压部),也可合并额叶、...     

Improved diagnosis of well‐differentiated hepatocellular carcinoma with gadolinium ethoxybenzyl diethylene triamine pentaacetic acid‐enhanced magnetic resonance imaging and Sonazoid contrast‐enhanced ultrasonography

Aim: Two new imaging modalities have been developed recently that are directed at the focal liver lesions: gadolinium ethoxybenzyl diethylene triamine pentaacetic acid (Gd‐EOB‐DTPA)‐enhanced magnetic resonance imaging (MRI) and Sonazoid contrast‐enhanced ultrasonography (CEUS). We investigated the usefulness of these modalities for the diagnosis of small (<2 cm), well‐differentiated hepatocellular carcinoma (HCC). Methods: A total of 15 nodules from 13 patients, which were histologically diagnosed as well‐differentiated HCC, were subjected to this study. Lesions that showed hypervascularity in the arterial phase and washout in the portal or late non‐hemodynamic phase were regarded as HCC in the dynamic studies of all imaging modalities. Results: By multidetector computed tomography (MDCT), six of 15 (40%) nodules were diagnosed as HCC. Gd‐EOB‐DTPA‐enhanced MRI diagnosed HCC in nine of the 15 (60%) nodules. Of the nine nodules that were not diagnosed by MDCT, four could be diagnosed by Gd‐EOB‐DTPA‐enhanced MRI. In Sonazoid CEUS, 10 of 15 nodules (67%) were diagnosed as HCC. Four of nine nodules that could not be diagnosed as HCC by MDCT, were diagnosed by Sonazoid CEUS. A total of 11 of the 15 (73%) nodules were diagnosed as HCC by Gd‐EOB‐DTPA‐enhanced MRI and Sonazoid CEUS in addition to MDCT. Conclusion: Gd‐EOB‐DTPA‐enhanced MRI and Sonazoid CEUS had greater diagnostic value for small, well‐differentiated HCC than did conventional MDCT.     

Effective aerosol delivery during high‐frequency ventilation in neonatal pigs

Background and objective: Pulmonary delivery of aerosols during high‐frequency oscillatory ventilation (HFOV) has not been studied in vivo. This study investigated the pulmonary delivery of aerosolized gadopentetate dimeglumine (Gd‐DTPA) in a HFOV circuit in piglets using MRI to visualize contrast excretion in the kidneys. Methods: Four ventilated piglets (3–7 days old, 1.7–2.4 kg at birth) received aerosolized Gd‐DTPA in a HFOV circuit for different durations of time (60, 30, 20 and 10 min). Aerosols were generated using the MiniHeart jet nebulizer. As MR‐compatible HFOV was not available, aerosolized Gd‐DTPA was administered in the HFOV circuit outside the MR suite followed by MRI 10–20 min later. T1‐weighted spin echo sequences were obtained using the Bruker/Siemens 4T MR scanner. Results: Enhancement of the kidneys was observed 10 min after aerosol initiation in piglets who received Gd‐DTPA aerosol for 60, 30 and 20 min in the HFOV circuit but not in the piglet who received aerosol for 10 min. Renal concentration of Gd‐DTPA, determined from the signal intensity, increased linearly with time until 40 min post Gd‐DTPA delivery. Conclusions: Effective pulmonary aerosol delivery during HFOV was confirmed by contrast visualization in the kidneys within 30 min of aerosol initiation reflecting, alveolar absorption, glomerular filtration and renal concentration.     

核磁共振动态增强扫描在前列腺癌诊断及鉴别诊断中的应用价值

目的 通过绘制时间信号强度曲线，探讨磁共振成像(MRI)快速序列动态增强在前列腺癌诊断及鉴别诊断中的价值。方法 对6例无泌尿系症状健康对照者、13例经病理证实的前列腺癌及32例前列腺增生患者行MR动态增强及延迟扫描，测量并计算病灶和正常组织的相对信号强度值，并绘制正常周围带、前列腺癌及增生的时间信号强度曲线。结果 正常周围带轻度强化，并缓慢上升至晚期(300s)达峰值(信号强度0．94～1．02)；32例前列腺增生患者于60s明显强化(信号强度1．11～1．29)并逐渐上升至240s时达峰值(信号强度1．50～1．68)后缓慢下降；13例前列腺癌患者中9例于60s时明显强化(信号强度1．30～1．j1)，并快速下降，4例T2WI影像上弥漫性病灶240～300s时明显强化。结论 正常周围带、前列腺癌及前列腺增生的动态强化方式明显不同，应用MR动态增强扫描对前列腺癌的诊断与鉴别诊断有较大的价值。     

A case of gliomatosis cerebri in an elderly woman

Gliomatosis cerebri is a rare form of glioma, which diffusely extends to both cerebral hemispheres. Because it sometimes fails to show severe neurological symptoms in spite of diffuse invasion, the antemortem diagnosis is difficult. We report a case of a 77-year-old woman, who was admitted with progressive left hemiparesis and dysarthralgia. Plain CT scan of the brain showed almost no abnormal findings. MRI T2-weighted image revealed widespread and nearly symmetrical extension of a high intensity area from the corpus callosum to the deep white matter of both cerebral hemispheres. Open biopsy of the brain showed glioblastoma multiforme, which finally confirmed the clinical diagnosis of gliomatosis cerebri. We also review the classic and recent literatures.     

Imaging findings of splenic hamartoma

AIM: To assess CT and MR manifestations and their diagnostic value in splenic hamartoma with review of literatures. METHODS: We described a woman who was accidentally found to have a splenic tumor by ultrasound of the abdomen. CT and MR findings of this splenic hamartoma were proved by pathology retrospectively. RESULTS: The CT and MR findings in this case included a ball-like mass with homogeneous mild-hypodensity lesions on non-enhanced CT scans or isointensity on T1-weighted images and mild hypointensity on T2-weighted images, progressive homogeneous enhancement on multiple-phase spiral CT and MR enhanced scans, and isodense enhancement on delayed post-contrast CT scans and obvious hyperintensity relative to the spleen on delayed MR images. CONCLUSION: Splenic hamartoma has some specific radiological features. However, the diagnosis of this disease must be based on clinical features and confirmed by pathology.     

磁共振轧喷酸葡胺增强扫描对脑囊尾蚴病退变期诊断价值的分析

目的　探讨用磁共振 (MR)轧喷酸葡胺 (Gd DTPA)增强扫描对脑囊尾蚴病退变期定性和定位诊断的价值。　方法　 6 9例行MR增强扫描诊断为退变期脑囊尾蚴病患者 ,并经手术或血清特异性囊尾蚴抗体检测证实 ,对比分析其MR平扫与增强扫描。　结果　 6 9例患者经MR平扫呈单发或多发 ,片状长T1、长T2异常信号 ,经MR增强扫描后T1加权像呈在大片低信号中见小结节状或环状强化 ,强化后的病灶直径最大不超过 2 2mm ,平均直径 8.1mm。其中 4例患者MR平扫呈单发病灶而经MR增强扫描后呈多发强化。　结论　退变期脑囊尾蚴病MR增强扫描有较典型的表现 ,且可明确病灶的数目、部位及受累范围 ,能提高鉴别诊断的准确性。     

MRI features of an atypical case of extraventricular neurocytoma: A case report

Rationale:Central neurocytoma occurring outside the ventricles is known as extraventricular neurocytoma (EVN). EVN is rare and its magnetic resonance imaging (MRI) findings vary greatly and overlap with the imaging features of other intracerebral primary tumors.Patient concerns:A 21-year-old woman with an intrauterine pregnancy of 18+2 weeks complained of dizziness and headache for 3 months.Diagnosis:A 8.6 cm × 5.8 cm × 3.7 cm space-occupying lesion was seen in the right frontal lobe on MRI, with mixed long signals on T1-weighted imaging and mixed slightly long signals on T2-weighted imaging, slightly hyperintense on T2-weighted imaging fluid attenuated inversion recovery images, and a large-scope long T1-weighted imaging and long T2-weighted imaging cystic component at the center of the lesion. A thick fence-like enhancement of the solid component at the periphery of the lesion was observed after injecting a contrast medium, while the internal cystic component was not enhanced. The MRI diagnosis was of glioma. The lesion was pathologically confirmed as an atypical central neurocytoma of the right frontal lobe.Interventions:Resection of the lesion and postoperative radiotherapy.Outcomes:The patient was lost to follow-up.Lessons:EVN can be considered as a differential diagnosis for lesions occurring in the cerebral hemispheres of young patients with cystic degeneration, thick fence-like enhancement, and peritumoral edema on MRI.     

不同分型脑囊尾蚴病患者影像学特征

目的 目的 探讨不同分型脑囊尾蚴病的影像学特征。方法 方法 对166例经临床确诊的脑囊尾蚴病患者的CT及MRI 表现进行回顾性分析。 结果 结果 166例脑囊尾蚴病患者中, 脑实质型108例, 脑室型15例, 脑膜型3例, 混合型40例。各型 脑囊尾蚴病CT、 MRI特点： ① 脑实质型脑囊尾蚴病可分为急性期型 （囊泡型、 脑炎型、 多发环形或结节状强化型） 和慢性 钙化型。囊泡型： CT表现为单发或多发囊状影, 边界清楚, 囊内可见高密度头节; MRI表现为类圆形长T1、 长T2信号, 囊 内可见偏心附壁的点状影, 囊壁及头节为等信号, 增强后无明显强化; 脑炎型： CT呈散在低密度灶, MRI表现为斑片状稍 长T1、 长T2信号, 多数无明显强化或不规则强化; 结节状或多发环形强化型： CT平扫为多发结节状低密度灶, 增强扫描 呈多发结节或环形强化; 慢性钙化型： CT表现为单发或多发的圆点状高密度影, MRI上表现为等或长T1、 短T2信号。② 脑室型： 常发生于第三、 四脑室, 可并发阻塞性脑积水。③ 脑膜型： 脑脊液间隙局限性扩大且不对称, 可出现交通性脑积 水, 增强扫描后可出现软脑膜强化。④ 混合型： 表现为上述2种或以上类型并存, 急、 慢性期影像混合存在。结论 结论 不同 分型脑囊尾蚴病影像学表现各不相同, 分析这些独特的影像学特征对脑囊尾蚴病患者的临床诊治及预后评判具有重要 意义。     

Estrogen Receptors and Polyamine Levels in Human Gastric Carcinoma

Background: Hepatic lesions constitute a daily challenge to radiology in clinical settings, and non‐invasive methods are valuable in the characterization of these liver tumours. We undertook our investigation to assess the lesion characterization potential of MRI by evaluating several unenhanced MR sequences and the dynamic gadolinium (Gd)‐enhanced technique. Methods: A total of 116 focal liver lesions in 116 patients were included in our retrospective study, and histological verification was available for 107 lesions. Nine haemangiomas had a follow‐up of 2 years. The 1.5‐T MR system was used. T1‐ and T2‐weighted sequences and dynamic Gd‐enhanced studies were evaluated by two individual readers as separate sequences and also collectively. Lesions were classified into benign or malignant, and a specific diagnosis was proposed. The McNemar test was used in statistical analysis, and interobserver variation was measured using kappa statistics. Results: Lesion classification into benign and malignant tumours (by evaluating all images in concert) was assessed in 83% and 89% of cases by readers 1 and 2, respectively. From single sequences, best lesion classification was achieved with Gd‐enhanced T1 by both readers. The difference in classification was statistically significant when all sequences were evaluated in comparison with any single sequence alone (P?=?0.02). Specific diagnosis was correctly determined using all sequences together in 60% and 71% of cases by readers 1 and 2, respectively. For individual sequences, correct diagnosis was most frequently proposed with a Gd‐enhanced T1‐weighted sequence by both readers (59% and 65% for readers 1 and 2, respectively). Conclusion: Multisequential MRI using Gd‐enhanced imaging performs extremely well in liver lesion classification, and with moderate ability to determine a specific diagnosis.