毛细胞黏液样星形细胞瘤:一种新确定的星形细胞胶质瘤

毛细胞黏液样星形细胞瘤(PMA)是WHO新近分类的胶质类肿瘤,既往被认为就是毛细胞型星形细胞瘤,然而PMA特有的临床发病年龄、部位、更具侵袭性的生物学行为及组织病理学特征使人们对它的认识逐渐增加.就PMA的流行病学、临床病理学、影像学特征等予以综述.     

毛细胞黏液样星形细胞瘤：一种新确定的星形细胞胶质瘤

毛细胞黏液样星形细胞瘤（PMA）是WHO新近分类的胶质类肿瘤,既往被认为就是毛细胞型星形细胞瘤,然而PMA特有的临床发病年龄、部位、更具侵袭性的生物学行为及组织病理学特征使人们对它的认识逐渐增加。就PMA的流行病学、临床病理学、影像学特征等予以综述。     

毛细胞黏液样星形细胞瘤的MRI表现及与毛细胞型星形细胞瘤的鉴别

目的探讨毛细胞黏液样星形细胞瘤(PMA)的MRI影像学特征。资料与方法对经手术病理证实的4例PMA的MRI资料进行回顾,分析PMA的MRI特征,并与毛细胞型星形细胞瘤(PA)进行比较。结果男、女各2例,发病年龄分别为4岁2例、13岁及22岁各1例。发病部位分别为鞍旁、丘脑、左颞叶及右侧小脑近中线各1例。肿瘤边界清楚,瘤周无水肿。MRI2例呈囊实性改变,2例呈均匀长T1、长T2信号,扩散加权成像(DWI)瘤体呈等信号,肿瘤内可有出血。增强后明显壁结节强化1例,3例均质环形中度强化,肿瘤囊壁轻度均匀强化,囊性部分不强化。结论PMA是一类瘤周无水肿、好发于近中线部位、多见于儿童的世界卫生组织(WHO)Ⅱ级的侵袭性星形细胞瘤。MRI作为PMA主要的影像检查手段,有助于术前诊断及与其他肿瘤的鉴别。     

毛细胞型星形细胞瘤影像学诊断现状

本文对毛细胞型星形细胞瘤的临床表现、病理表现、影像学诊断、鉴别诊断的进展进行了介绍,着重介绍毛细胞型星形细胞瘤MR影像学诊断现状以及黏液性毛细胞型星形细胞瘤的特殊影像学表现。     

脑星形细胞瘤的CT表现与血管生成的相关性研究

目的探讨脑星形细胞瘤的CT表现与其肿瘤血管生成的关系.材料和方法分析手术病理证实的82例脑星形细胞瘤的CT表现.采用免疫组织化学染色方法,染色血管内皮细胞第八因子相关抗原,标记微血管,然后测定微血管密度(MVD),并分析MVD与CT表现的相关性.结果星形细胞瘤的MVD越大,恶性程度越高,预后越差.星形细胞瘤CT密度的不均匀性、瘤周水肿、占位效应及增强程度与MVD明显相关,但星形细胞瘤的大小、部位与MVD无明显关系.结论星形细胞瘤的CT征象能反映星形细胞瘤的血管生成活性,术前分析星形细胞瘤的CT征象与MVD的关系,能更好的指导选择临床治疗方案和评估预后.     

磁敏感成像在脑星形细胞瘤分级中的价值

目的:探讨磁敏感成像(SWI)在脑星形细胞瘤分级中的价值.材料和方法:分析18例经病理证实的脑星形细胞瘤,低级别弥漫性星形细胞瘤7例、间变性星形细胞瘤级3例和多形性胶质母细胞瘤级8例的SWI特点.结果:7例低级别弥漫性星形细胞瘤均未见瘤内静脉血管影,肿瘤周围均轻度水肿.3例间变性星形细胞瘤与8例多形性胶质母细胞瘤内均见丰富静脉血管影.1例间变性星形细胞瘤和6例多形性胶质母细胞瘤内均见出血灶,所有间变性星形细胞瘤与多形性胶质母细胞瘤瘤周中至重度水肿.结论:磁敏感成像能提供瘤内出血、瘤周水肿及瘤体血供等特点,对星形细胞瘤分级尤其是高、低级别的判断有重要价值.     

脑星形细胞瘤MRI表现与血管内皮生长因子表达的关系

目的:探讨脑星形细胞瘤血管内皮生长因子的表达与MRI表现的关系.材料和方法:收集手术病理证实的脑星形细胞瘤42例,分析其M RI表现.采用免疫组织化学技术染色VEGF,并分析其表达程度与M RI表现的关系.结果:星形细胞瘤的VEGF表达与其病理分级、患者复发密切相关.星形细胞瘤MRI信号的不均匀性、边界清楚与否、瘤周水肿范围、占位效应及增强程度与VEGF表达明显相关,但星形细胞瘤的大小、部位与VEGF表达无明显相关性.结论:星形细胞瘤的MRI征象能反映星形细胞瘤的VEGF表达.术前分析星形细胞瘤的MRI征象与VEGF表达的关系,能更好地指导临床治疗方案的选择和评估患者的预后.     

星形细胞瘤影像学诊断及WHO新分类法的介绍

1993年ＷＨＯ公布了新的脑肿瘤组织学分类 ,即蓝皮书第二版 (ｈｉｓｔｏｌｏｇｉｃａｌｃｌａｓｓｉｆｉｃａｔｉｏｎｏｆｔｕｍｏｕｒｏｆｔｈｅｃｅｎｔｒａｌｎｅｒｖｏｕｓｓｙｓｔｅｍＥＤⅡ )。将星形细胞肿瘤 (ａｓｔｒｏｃｙｔｉｃｔｕｍｏｕｒｓ)分为局限性和弥漫性两类。弥漫性星形细胞肿瘤包括低度恶性星形细胞瘤、间变性星形细胞瘤和多形性成胶质细胞瘤。它们呈弥漫性、浸润性生长 ,即Ⅱ～Ⅳ级星形细胞瘤。而局限性者包括局限性生长的毛细胞型星形细胞瘤、多形性黄色星形细胞瘤 (系旧分类中没有的 )、室管膜下巨细胞星形细胞瘤…     

一例枕大孔区不典型毛细胞型星形细胞瘤影像学表现

<正>毛细胞型星形细胞瘤(pilocytic astrocytomas, PA)是WHO Ⅰ级星形细胞瘤胶质瘤,是儿童最常见的后颅凹良性星形细胞瘤^[1];成人很少发生PA,通常预后良好^[2-3]。正确的术前诊断是选择手术方法的先决条件。因此,PA术前准确诊断对治疗策略的制定以及改善患者预后有重要意义。PA的典型影像学特征为MRI上显示境界清晰的囊性肿块,并伴有均匀显著强化的实性结节[4]。影像学表现为无强化的实性肿块极为罕见^[3,5-6],     

儿童期小脑星形胶质细胞瘤的MRI特征

目的　探讨小脑星形胶质细胞瘤的组织类型与MRI表现特征。方法　对 3 1例经病理证实的小脑星形胶质细胞瘤组织类型和MRI表现进行回顾性分析。结果　 3 1例小脑星形胶质细胞瘤中 ,3 0例 (96.8% )组织学证实为毛细胞型星形胶质细胞瘤 ;1例 (3 .2 % )为非毛细胞型星形胶质细胞瘤。MRI表现分为以下五型 :(1)假囊伴壁结节型 ,占 3 8.7% ;(2 )假囊型 ,占 16.1% ;(3 )囊性伴壁结节型 ,占 2 9% ;(4 )实质型 ,占 12 .9% ;(5 )移行型 ,占 3 .2 %。结论　毛细胞型星形胶质细胞瘤是儿童期小脑最常见的良性肿瘤 ,肿瘤在生长过程中可发生坏死和囊变 ,从实质型向其它各型演变。毛细胞型肿瘤血管为有孔型毛细血管 ,MRI增强可见肿瘤活性部分有明显强化     

Imaging characteristics of pilomyxoid astrocytomas in comparison with pilocytic astrocytomas

Purpose

Pilomyxoid astrocytoma (PMA) is a recently described astrocytic tumor that has been previously diagnosed as pilocytic astrocytoma (PA). The purpose of this study was to describe the imaging features of PMAs in comparison with PAs.

Materials and methods

We retrospectively reviewed CT/MR images and medical records of 10 patients with PMA and 38 patients with PA. The mean ages of patients with PMA and PA were 10 and 15 years, respectively. Imaging features including location, composition, enhancement pattern, presence of calcification, hemorrhage, and leptomeningeal dissemination were compared in patients with two tumor types.

Results

Six PMAs (60%) occurred at the suprasellar area and the cerebellum was the most common (45%) site of PA. Solid component was dominant in eight PMAs (80%) and in 19 PAs (50%). All of the PMAs containing solid mass (n = 8) included non-enhancing portion while 12/37 (32%) PAs included non-enhancing solid portion (p < 0.05). Leptomeningeal dissemination was noted in five PMAs (50%) and one PA (3%) (p < 0.05). Other imaging findings were not significantly different.

Conclusion

A younger age, more frequent occurrence at the suprasellar area, mainly solid mass containing non-enhancing portion, and more frequent leptomeningeal dissemination are helpful differential features of PMAs as compared to PAs.     

颅内毛细胞星形细胞瘤的MRI特点分析

目的总结颅内毛细胞星形细胞瘤的MR特点。方法回顾性分析经手术、病理证实15例毛细胞星形细胞瘤的MRI表现,MRI扫描包括平扫T1WI、T2WI、水抑制和T1WI增强。结果鞍区(n=5),小脑(n=4),基底节(n=3),侧脑室、脑干、四脑室各1例。在MRI上实性肿瘤(n=4)T1WI为低、等信号,T2WI为稍高、高信号,呈不均匀明显强化。囊实性肿瘤(n=11)的实性成分(包括合并壁结节的3例)T1WI呈不均匀低、稍低信号,T2WI为不均匀等、稍高、高信号,呈不均匀明显强化或不规则环形强化;囊性成分T1WI为均匀低信号,T2WI为均匀高信号,囊液可被抑制(n=7)或不被抑制(n=4),囊壁为明显、轻度强化或不强化。伴出血、钙化各1例。粘液性毛细胞星形细胞瘤1例。结论该病多见于小脑和鞍区,实性或囊实性,可有出血、钙化;若合并周围组织侵犯、脑脊液播散,要考虑粘液性毛细胞星形细胞瘤。     

纤溶酶原激活抑制因子1基因在人脑星形细胞瘤中的表达及意义

采用Ｎｏｒｔｈｅｒｎ ｂｌｏｔ分子杂交和ＡＢＣ免疫组化方法检测３６例人脑星形细胞瘤纤溶酶原激活抑制因１基因ｍＲＮＡ和蛋白表达，所有星形细胞瘤组织均可表达３．０ｋｂ和２．２ｋｂ的ＰＡＩ－１ ｍＲＮＡ转录物，高级别星形细胞瘤ＰＡＩ－１ ｍＲＮＡ表达水平显著高于低级别星形细胞瘤，ＰＡＩ－１display status     

囊性毛细胞型星形细胞瘤的MRI诊断

目的探讨MR I对囊性毛细胞型星形细胞瘤的诊断价值。方法回顾性分析26例经手术病理证实的囊性毛细胞型星形细胞瘤MR I表现,研究肿瘤的部位、形态和信号特征。结果肿瘤位于大脑半球6例,小脑20例,依据MR I表现,可分为单纯囊性、囊性伴壁结节。结论囊性毛细胞型星形细胞好发于年轻人,最常见于小脑,有较典型MR I表现,因此根据MR I表现结合临床资料,可望做出定性诊断。     

Proton magnetic resonance spectroscopy of brain tumors correlated with pathology

RATIONALE AND OBJECTIVES: Evaluate proton magnetic resonance spectroscopy ((1)H-MRS) for assessing and grading brain tumors. MATERIALS AND METHODS: The research was done at Detroit Medical Center in a 1.5-T Siemens MR magnet using single-voxel or multivoxel MRS. This study consisted of 27 patients: 10 females and 17 males ages 22-83 years (average age 43.8). The data were recorded for three peaks-N-acetyl aspartate (NAA), choline (Cho), creatine (Cr)-which were used to calculate the ratios Cho/NAA and Cho/Cr. RESULTS: Abnormal spectra were seen in 25 patients and normal spectra in 2. In 16 patients with brain astrocytoma of various grades, the pathology grading was correlated with Cho/NAA and Cho/Cr. These values were 6.53 and 3.35 for nine patients with Grade 4 astrocytoma; 1.85 and 1.62 for three patients with Grade 3 astrocytoma; 2.21 and 1.50 for three patients with Grade 2 astrocytoma; and 1.45 and 1.49 for one patient with Grade 1 astrocytoma. The remaining nine patients with abnormal spectra were also correlated with pathology. CONCLUSION: MRS ratios can be used to differentiate malignant and nonmalignant lesions from normal brain tissue. In general, high-grade astrocytoma have higher Cho/NAA and Cho/Cr ratios compared with low-grade astrocytoma.     

A rare,pediatric, fourth-ventricular,anaplastic astrocytoma

Anaplastic astrocytoma, a diffusely infiltrating, malignant, astrocytic, primary brain tumor, is most commonly observed between 30 and 50 years of age. Anaplastic astrocytomas are now classified as WHO grade III lesions, with imaging characteristics and prognosis between diffuse low-grade astrocytomas (WHO grade II) and glioblastomas (WHO IV). Anaplastic astrocytoma can appear mostly in the cerebrum followed by cerebellum. However, it is rarely observed in the fourth ventricle. In this article, we aimed to describe an uncommon case of a pediatric, fourth-ventricular, anaplastic astrocytoma. A 9-year-old male who underwent MRI brain then adopted gross-total tumor eradication. The final histopathology findings were consistent with an anaplastic astrocytoma.     

Dependent layering of contrast medium in cystic astrocytomas

Summary Dependent layering of contrast enhanced fluid in cystic astrocytomas has not been described on computed tomograms. Two children in which this phenomenon occurred are described and its significance is discussed. In a third cystic lesion contrast layering was confirmed by head tilting.     

Primary adult unilateral thalamic pilocytic astrocytoma with von Recklinghausen's disease mimicking lymphoma: A case report

Thalamic astrocytomas are rare central nervous system tumors that account for 1%-1.5% of all brain tumors. Their Clinical features depend on anatomical involvement. For these tumors, gross total resection is so difficult due to their deep location and also the infiltration of the optic pathway or brain stem. Unilateral adult thalamic locations are rarely described in the literature. Their radiological features often suggest lymphoma. The authors report here a new case of a primary unilateral thalamic pilocytic astrocytoma mimicking lymphoma diagnosed after a stereotactic core biopsy in a 62-year-old male patient with von Recklinghausen''s disease and which is responsible for Dejerine–Roussy syndrome. The authors will proceed with a comprehensive review of literature regarding this rare entity.