Intraocular tumors: evaluation with MR imaging

Sixty-seven ocular tumors were studied with magnetic resonance (MR) imaging and computed tomography (CT). These tumors included primary uveal melanoma (n = 55), circumscribed choroidal hemangioma (n = 3), diffuse choroidal hemangioma (n = 1), retinal capillary hemangioma (n = 1), medulloepithelioma (n = 1), choroidal nevus (n = 1), retinoblastoma (n = 1), and choroidal metastases (n = 4). MR imaging demonstrated all these lesions, while CT demonstrated 88%. Associated retinal detachment was more easily distinguished from the neoplasms with MR imaging. Extrascleral extension of melanoma and hemorrhagic cystic necrosis within the melanoma were clearly demonstrated with MR imaging, but not with CT. Ninety-three percent of melanomas were markedly hyperintense, compared with the intensity of the vitreous body, on T1-weighted images and hypointense on T2-weighted images. All metastatic lesions were isointense on T1-weighted images and hypointense on T2-weighted images. The circumscribed choroidal hemangiomas were hyperintense on T1-weighted images and isointense on T2-weighted images. MR imaging is superior to CT in detection of intraocular tumors and may be more specific in diagnosis.     

盆部原发肿瘤CT表现特征及其解剖学基础

目的分析盆部原发肿瘤CT增强表现特征，探讨产生各种影像表现的病理学和解剖学基础。方法回顾性分析14例经病理学证实的盆部原发肿瘤CT增强表现，包括病灶大小、密度、边缘、强化特征，肿块所在的解剖部位及其与邻近组织器官和间隙的关系等。结果良性肿瘤3例，恶性肿瘤11例。肿块位于盆腹膜腔和腹膜外间隙各6例，盆腹膜腔和腹膜外间隙同时受累2例。CT增强表现为实质性8例，囊实性6例；均匀强化3例，不均匀强化11例。肿块周围脂肪间隙清晰和受侵犯各7例。4例病灶内出现钙化，其中良性畸胎瘤2例，恶性畸胎瘤和类癌各1例。结论CT增强扫描能准确判断盆部原发肿瘤的解剖位置及其与邻近解剖结构的毗邻关系，初步判断肿瘤的良恶性，对畸胎瘤能做出比较明确的定性诊断。     

眼球肿瘤的CT和MRI表现及其临床价值

目的：探讨眼球肿瘤的CT和MRI表现及其在诊断和鉴别诊断中的价值。资料与方法：73例眼球肿瘤行CT扫描，45例行MRI扫描，回顾性分析眼球肿瘤的CT和MRI表现。结果：28例视网膜母细胞瘤CT表现为有钙化的肿块；26例色素膜黑色素瘤MRI显示为短T1短T2信号，增强后轻至中度强化；9例脉络膜骨瘤CT表现为眼球壁高密度扁平性肿块；6例转移瘤MRI表现为扁平性肿块，呈略长T1长T2信号；4例脉络膜血管瘤呈长T1明显长T2信号，增强后明显均匀强化。结论：CT和MRI可显示眼球肿瘤的形态、大小及内部特征，有助于诊断和鉴别诊断。     

颈静脉孔区肿瘤的CT和MRI诊断

目的：探讨CT和MRI对颈静脉孔区肿瘤的诊断及鉴别诊断。方法：回顾性分析了经手术病理证实的34例颈静脉孔区肿瘤的CT和MR影像资料,其中包括颈静脉球瘤12例,神经鞘瘤10例,转移瘤3例,脑膜瘤2例,神经纤维瘤、脊索瘤、软骨瘤、软骨肉瘤、纤维脂肪瘤、纤维血管瘤和先天性囊肿各1例。CT检查21例,其中15例作增强扫描。MRI检查31例,其中24例加作MR增强扫描。结果：肿瘤内纡曲流空的血管即“椒-盐”征是颈静脉球瘤的特征性MRI表现。神经鞘瘤易发生囊变,注射对比剂后肿瘤中度强化。转移瘤骨质破坏不规则。脑膜瘤增强扫描可见脑膜“尾巴”征。软骨瘤和软骨肉瘤可见明显钙化。结论：CT与MRI相结合能更全面地为临床提供诊断、鉴别诊断及治疗所需要的信息,为治疗方法的选择提供可靠的依据。     

眼球肿瘤的CT表现

目的 研究眼球肿瘤的CT表现,并探讨其在诊断和鉴别诊断中的价值。材料与方法 回顾性分析22例经病理或临床证实的眼球肿瘤的CT表现。结果 成视网膜细胞瘤14例,脉络膜黑色素瘤5例,睫状体神经鞘瘤1例,脉络膜骨瘤1例,脉络膜血管瘤1例。其CT表现各具有特征。结论 CT可清楚显示眼球肿瘤的形态、大小和强化特征,为诊断和鉴别提供重要依据。     

头颈部孤立性纤维瘤的影像学表现

目的：探讨头颈部孤立性纤维瘤(SFT)的影像特征,提高对该病的认识。方法回顾性分析10例经手术病理证实的头颈部 SFT 患者的 CT 和 MR 表现。10例均行 CT 平扫及双期增强扫描、2例行 MR 检查。结果10例病灶均表现为孤立的肿块,最大径20~115 mm,中位最大径约35.5 mm。肿瘤发生于眼眶2例、鼻腔鼻窦4例,腮腺、面颊、锁骨上区及枕部各1例。病变边界清楚8例、模糊2例,呈椭圆形7例,分叶状3例。CT 平扫呈等或稍低密度,其中4例密度均匀,6例密度不均匀(2例见多发囊变区,1例见结节状钙化灶)。增强后9例呈明显均匀(n=3)或不均匀(n=6)强化,1例呈轻度均匀强化。CT 双期增强强化模式包括快速强化缓慢廓清8例、快速强化快速廓清1例和延迟强化1例。与脑实质相比,T1 WI 呈均匀等信号1例,等、低混杂信号1例;T2 WI 呈均匀等信号1例,等、高混杂信号(多发囊变)1例;增强后分别呈均匀和不均匀显著强化。结论头颈部不均匀的富血供肿瘤要考虑到 SFT 的可能。瘤体 T2 WI 与脑实质相比呈等或稍低信号,CT 增强扫描明显强化,双期增强呈快速强化缓慢廓清的强化模式可能是有诊断价值的影像特点。     

颅底骨源性肿瘤的MRI影像诊断

目的：分析颅底骨源性肿瘤的ＭＲＩ表现并与ＣＴ和病因对照，研究ＭＲ在诊断中的价值与限度。材料与方法：搜集了经手术病理证实的颅底骨源性肿瘤２２例（软骨肉瘤３例，软骨瘤２例，转移瘤２例，脊索瘤１０例，骨巨细胞瘤２例，恶性纤维组织瘤１例，骨化性纤维瘤２例），全部行ＭＲ检查（１１例行增强检查），８例行ＣＴ检查。结果：绝大部分肿瘤均有一清晰的边缘，Ｔ１Ｗ上呈低或等信号，Ｔ２Ｗ上呈不均匀高信号，Ｔ１Ｗ上呈低信号     

Focal nodular hyperplasia: CT findings with emphasis on multiphasic helical CT in 78 patients

PURPOSE: To evaluate features of focal nodular hyperplasia (FNH) at multiphasic helical computed tomography (CT). MATERIALS AND METHODS: Clinical, pathologic, and preoperative imaging findings were retrospectively reviewed in 78 patients. Conventional liver CT was performed in nine patients; helical multiphasic CT, in 69. Diagnosis was based on complete resection (n = 20), biopsy (n = 42), or clinical and imaging follow-up for a minimum of 6 months (n = 16). Number, size, location, margins, surface, homogeneity of enhancement, and presence of a central scar, mass effect, exophytic growth, calcification, pseudocapsule, or vessels feeding or draining the lesion were evaluated. RESULTS: CT depicted 124 tumors (mean diameter, 4.1 cm; range, 1-11 cm); 62 were small (< or =3 cm). FNHs were hypervascular and hyperattenuating to liver on 106 of 106 arterial phase scans and were isoattenuating to liver on 82 of 89 delayed scans. Of the 124 tumors, 111 enhanced homogeneously, 109 had a smooth surface, 101 were subcapsular, 89 had ill-defined margins, and 62 had a central scar that was observed more often in large lesions (40 of 62 lesions) than in small lesions (22 of 62 lesions). FNHs less frequently exerted a mass effect (43 lesions), had vessels around or within the lesion (42 lesions), demonstrated exophytic growth (40 lesions), or showed a pseudocapsule (10 lesions). Only one FNH had calcification. CONCLUSION: Helical CT demonstrates characteristic features that may allow confident diagnosis of FNH. In typical cases, neither biopsy nor further imaging is necessary.     

儿童头颈部横纹肌肉瘤的CT及MR影像学特点

 目的 探讨儿童头颈部横纹肌肉瘤(rhabdomyosarcoma,RMS)的CT及MR影像学特点。方法 回顾性分析29例病理证实的儿童头颈部RMS的影像学资料,其中23例行MRI检查,18例行CT检查。结果 10例发病部位位于鼻咽部,4例位于鼻腔及鼻窦,5例位于鼻翼部,3例位于颌面部,6例位于耳部,1例位于左侧颞下窝。肿瘤形态不规则,呈浸润性生长,多侵蚀破坏邻近骨质。CT图像病灶密度不均匀,瘤体内均无钙化。MR检查T₁WI呈等或稍低信号,T₂WI呈稍高信号,信号不均匀,增强后瘤灶明显不均匀强化。8例侵犯眼眶,13例进入并侵犯鼻腔,14例侵犯副鼻窦,15例侵犯颞骨乳突,12例侵犯颞骨岩部,14例突破颅底,累及硬脑膜,同时4例侵犯邻近脑组织,2例发生脑脊液转移。结论 儿童头颈部RMS好发于脑膜旁区。CT能够很好地显示肿瘤对周围骨质结构的破坏,而MR能更清楚显示肿瘤软组织受累范围,两者结合可提供更全面的影像信息。     

Cerebral hydatid disease CT and MR findings

In this study, we reviewed the computed tomography (CT, n=9) and magnetic resonance (MR, n=5) imaging findings of 11 patients with pathologically confirmed cerebral hydatid disease. Among our patients, there were 10 cases of Echinococcus granulosus and 1 case of Echinococcus multilocularis. Common CT and MR imaging findings of E. granulosus lesions were well-defined, smooth thin-walled, spherical, homogeneous cystic lesions with no contrast enhancement, no calcification, and no surrounding edema. E. multilocularis lesions showed calcified round, solid pattern with definite margins, contrast enhancement, and surrounding edema.     

Basal cell adenoma of the parotid gland: characteristics of 2-phase helical computed tomography and magnetic resonance imaging

OBJECTIVE: The goal of this study was to report the radiologic characteristics of basal cell adenoma of the parotid gland, which is a relatively rare neoplasm. METHODS: A radiology and otolaryngology specialist reviewed the 2-phase helical computed tomography (CT) (n = 6) and/or magnetic resonance (MR) imaging (n = 2) scans of 7 patients with basal cell adenoma. The authors evaluated the imaging characteristics, including tumor size, location, contour and margin, internal density or signal intensity, contrast enhancement pattern, and presence of calcification. The imaging features were then analyzed and correlated with the pathologic findings. RESULTS: All the tumors presented as small (less than 3 cm), well-encapsulated, round or oval masses on CT or MR imaging. On the 2-phase CT scan, the mostly solid-looking tumors (n = 4) showed marked contrast enhancement on the early phase, and there was a subsequent decrease in attenuation on the delayed phase. These tumors were classified as the solid subtype on histologic examination. Meanwhile, the tumors with large cystic areas (n = 2) showed gradual and additional enhancement on the delayed phase and were classified as the tubular or trabecular subtype on pathologic evaluation. There were small spots of low attenuation in the tumors of the solid subtype, which were proved to be intratumoral microcysts in the pathologic correlation. Calcification was found in a tumor. CONCLUSIONS: Basal cell adenomas of the parotid gland present as small well-marginated tumors and appear as masses with central large cysts or solid masses with microcysts on CT and MR imaging scans. Basal cell adenomas of the parotid gland had at least 2 different enhancement patterns on the 2-phase helical CT scans, and the enhancement patterns and imaging architecture were related to the histologic subtype of the tumors.     

Castleman病的影像学表现与手术、病理对照分析

目的探讨Castleman病的CT、MR及血管造影的影像学特征,以期在术前做出正确诊断。方法回顾性分析经手术、病理证实的16例Castleman病患者的临床、影像、手术及病理资料。结果 16例患者按病理分型:透明血管型12例,浆细胞型1例,混合型3例。按临床分型:为局灶型13例,多中心型3例。影像学表现:CT扫描15例,平扫表现病灶为直径1.3～20 cm[平均(6.21±4.75)cm]大小的单发、多发结节或软组织肿块,其中1例盆腔病变内可见簇状钙化;增强扫描病灶动脉期显著强化且与动脉几乎同步强化;浆细胞型病灶呈轻-中度强化。MR检查4例,MRI 2例,1例考虑盆腔海绵状血管瘤可能,1例后纵隔囊性占位,MRI+MRA 1例,诊断Castleman病,MRA 1例诊断为颈动脉体瘤,此例同时做数字减影血管造影,诊断为甲状腺实质性肿瘤。结论透明血管型Castleman病的影像表现与病理类型密切相关,CT及MRI增强表现有其特征,具有重要的诊断价值。而浆细胞型Castleman病影像表现不典型,术前诊断困难。     

松果体区肿瘤的CT诊断

目的：探讨松果体区肿瘤的CT表现，其诊断提供帮助。方法：对17例松果体区肿瘤行CT扫描，其中2例行MR和血管造影检查。结果：生殖细胞瘤11例，CT平扫多为高密度肿块,有显著强化。松果体钙斑增大，被包埋为特征性表现。常可直接侵犯第三脑室，致脑室内壁线状强化，也可沿脑脊液播散。本组另见畸胎瘤1例，脑膜瘤1例，胶质瘤4例。结论；CT扫描基本反映了松果体区肿瘤的特点，结合临床病史、性别、年龄等资料综合分析，大部分病例可作为定性诊断，对不典型病例诊断困难.     

腮腺基底细胞腺瘤的CT与MRI表现

目的:探讨腮腺基底细胞腺瘤(BCA)的CT和MRI表现。方法:回顾性分析10例腮腺BCA的CT和MRI表现。10例中男3例,女7例;右侧腮腺4例,左侧6例。结果:10例肿瘤均为单发,肿瘤最长径平均为2.4cm。10例肿瘤中不规则形或深分叶状2例,圆形或类圆形8例;边缘均光滑清楚。MRI检查2例,表现为长T1、短T2信号实性肿块,伴稍低信号包膜,增强扫描后病灶呈均匀明显强化。CT检查8例:6例呈实性,2例呈囊实性、内有大片液化囊变,实性部分明显强化。结论:腮腺BCA的CT和MRI表现有一定特征,结合临床,有助于本病的诊断和鉴别诊断。     

磁共振在眼球常见恶性肿瘤诊断中的价值

目的通过分析眼球常见恶性肿瘤的磁共振影像学表现特征,以提高对眼球恶性肿瘤的认识。方法回顾分析经手术病理及临床证实27例眼球恶性肿瘤病例的磁共振影像表现。结果总计眼球恶性肿瘤27例,其中葡萄膜黑色素瘤19例,表现为突向眼球内结节状、蘑菇状影,多数T₁WI呈高信号、T₂WI呈低信号,增强后病灶轻度或中度强化;葡萄膜黑色素细胞瘤恶变1例,表现为突向眼球内结节状影,T₁WI呈高信号、T₂WI呈低信号,增强后病灶中度强化;视网膜母细胞瘤4例,表现为眼球内突向玻璃体内肿块状影,T₁WI呈等信号、T₂WI呈等低信号,增强后病灶轻度或中度强化;脉络膜转移瘤2例,表现眼球后壁半球、扁平样突起影,T₁WI呈稍高信号,T₂WI呈稍低信号,增强后病灶中度强化,边缘强化明显。眼球内淋巴瘤1例,表现为眼内T₁WI信号增高,眼球内软组织结节影,T₁WI呈等信号、T₂WI呈等低信号,增强后病灶轻度强化。结论磁共振检查能够准确反映眼内常见恶性肿瘤的发生部位、大小及范围等影像特征,为临床治疗方法的选择提供重要的影像学依据。     

眼球脉络膜血管瘤的影像学表现

目的：探讨眼球脉络膜血管瘤的CT、MRI表现及其诊断、鉴别诊断价值。方法：回顾性分析9例经病理（3例）和临床证实（6例）的脉络膜血管瘤。CT扫描6例，MR检查4例，9例均行B超检查，3例作了眼底荧光血管造影。结果：2例CT平扫示眼球后极球壁轻度或新月形增厚，与球壁呈等密度，5例（1例平扫＋增强）增强示眼球后极部高密度梭形或扁平状隆起均匀肿块，瘤体强化明显。与玻璃体比较3例MR T1WI呈高信号，T2WI呈低信号，与视神经、眼外肌相比呈等信号；1例较小肿瘤辅以增强T1WI脂肪抑制技术被清楚显示。渗出性视网膜脱离在T1WI、T2WI上均呈中、高信号；增强T1WI瘤体显著强化，边界清晰，且信号均匀。B超检查8例为实质不均质肿块占位，1例为均质肿块占位，9例均探及视网膜脱离光带。结论：CT＋MRI＋B超检查对脉络膜血管瘤可得到较为全面的影像学诊断资料，MRI在该病的诊断及鉴别诊断中较CT及B超更具敏感性和特异性。     

泪腺恶性上皮性肿瘤的CT、MRI诊断

目的 总结泪腺恶性上皮性肿瘤的CT和MRI表现.方法 回顾性分析16例经病理学证实的泪腺恶性上皮性肿瘤CT和MRI影像资料.结果 16例泪腺恶性上皮性肿瘤,15例位于泪腺窝,1例位于眶缘前.5例呈类圆形,11例呈不规则形(其中9例后缘变尖,5例沿眶壁前后方向或上下方向生长),8例泪腺窝骨质受压,6例眶壁骨质破坏,1例眶壁骨质硬化;3例侵犯颅内;1例见额部皮下转移灶;2例CT可见钙化.MRI示肿瘤呈等、长T_1长T2信号,增强扫描可见强化.结论 CT及MRI可显示泪腺恶性上皮性肿瘤的特征,有助于泪腺恶性上皮性肿瘤的诊断及鉴别诊断.     

颅内血管外皮细胞瘤的MRI及CT诊断

目的:探讨颅内血管外皮细胞瘤的MRI及CT影像学特点,以提高诊断水平。材料和方法:回顾性分析经手术病理证实的颅内血管外皮细胞瘤4例。4例均行MRI扫描,其中2例并行CT扫描。结果:4例血管外皮细胞瘤分别位于前、中颅窝、右侧桥小脑角区及右顶部各1例,均呈明显分叶状。T1WI示肿瘤呈高或等、低混杂信号,T2WI示肿瘤呈等或等、高混杂信号。增强扫描示肿瘤实性部分高度增强,其中4例肿瘤周边均可见不同程度水肿带,3例见流空血管影,1例肿块内见坏死囊变灶、1例邻近颅骨骨质破坏,1例见幕上轻度脑积水。CT平扫示肿瘤呈高密度,未见瘤内钙化、邻近颅骨骨质增生及脑膜尾征等脑膜瘤常见征象。结论:MRI及CT表现对颅内血管外皮细胞瘤的诊断有一定的作用,最终诊断依靠病理。     

动态增强CT扫描对肾嫌色细胞癌的诊断价值

目的评价动态增强 CT 扫描对肾嫌色细胞癌的诊断价值.资料与方法回顾性分析13例经手术病理证实的肾嫌色细胞癌的 CT 影像资料,包括瘤体平扫、增强各期 CT 值的测量,强化程度及方式(均匀、不均匀或周边强化)的判断,并观察肿瘤有无钙化、囊变、外侵及转移(肾周改变、静脉癌栓及淋巴结转移).结果13例肾嫌色细胞癌中,6例肿瘤呈均匀软组织密度,5例肿瘤显示钙化,2例肿瘤出现囊变.动态增强 CT 扫描皮髓期(CMP)和肾实质期(NP)肿瘤平均 CT 值分别为(70.23±16.55)Hu、(80.38±21.85)Hu,两者差异无统计学意义(P >0.05),但所有病灶密度均明显低于肾皮质(P <0.05);NP 瘤体强化程度明显低于周围正常肾实质(P <0.05).6例瘤体可见均匀强化,5例可见中心瘢痕,其中1例可见轮辐状强化.结论肾嫌色细胞癌的动态增强 CT 表现有一定特征性,均匀强化结合钙化及瘢痕表现有助于诊断及鉴别诊断.     

胸部节细胞神经瘤的CT和MRI表现

目的 探讨胸部节细胞神经瘤的CT及MRI表现,提高对该病的诊断和鉴别诊断能力.方法 回顾性分析20例经手术病理证实的胸部节细胞神经瘤的临床、CT(14例)、MR(6例)平扫和增强扫描及所有病理学资料.结果 20例胸部节细胞神经瘤中,发生于后纵隔17例、侧胸膜2例、右侧整个胸腔1例.14例肿瘤平扫CT值20～40 HU,平均30.5 HU,4例伴有小结节状钙化,1例伴有斑片状脂肪密度影;动脉期增强CT值0～12 HU,平均6.2 HU,延迟期增强10～20 HU,平均14.3 HU.MRI检查5例在T1 WI上为均匀低信号,1例在T1WI上低信号内夹杂斑片状高信号脂肪影;T2WI上6例为不均匀高信号,其中1例呈旋涡状征象;增强后动脉期呈轻度不均匀强化,延迟期逐渐进行性轻度强化.结论 增强后CT及MRI显示肿瘤在动脉期不强化或轻微强化、延迟后逐渐轻度强化是胸部节细胞神经瘤的特征性表现.