钙化上皮瘤的影像表现及病理基础

【摘要】目的：分析钙化上皮瘤的CT及MRI表现,并探讨其病理基础。方法：回顾性分析17例经手术病理证实的钙化上皮瘤患者影像学资料并复习相关文献,其中8例行CT平扫及增强扫描,6例行MR平扫及增强检查,2例仅行CT平扫,1例先行X线片,后行MR平扫加增强检查。结果：10例CT共13个病灶。8个病灶见钙化,其中5个病灶完全钙化。2个病灶见坏死。10个病灶边界清清楚,3个瘤周见絮状稍高密度影。8例CT增强扫描共11个病灶,其中3个轻度强化,5个不均匀中度强化,3个病灶完全钙化无强化。6例MR均为单发,2例T1WI呈等信号,T2WI呈外周高中央低信号,DWI呈环状高信号,增强呈“环靶征”。2例T1WI呈等或稍高信号,T2WI呈高信号,内见微囊状更高信号,灶周可见斑片状高信号,增强不均匀强化。2例T1WI呈稍低信号,T2WI均呈稍高信号,增强不均匀强化。1例X线片呈高密度,T1WI呈低信号,T1WI压脂呈不均匀稍高信号,T2WI压脂呈高低混杂信号,增强扫描不均匀强化,以中央强化较为明显。结论：钙化上皮瘤的影像表现有一定特征,当病灶位于皮下,边界清楚,CT见广泛泥沙样或致密的局灶性钙化,MR上见微囊状改变,增强扫描轻至中度强化,尤其呈“环靶征”表现时,应考虑到PM的诊断。     

Imaging Features of Intracranial Angioleiomyoma (2 Cases Discussion)

目的 探讨颅内血管平滑肌瘤的CT及MRI表现.资料与方法 结合文献回顾性分析2例经手术病理证实的位于颅内鞍旁的血管平滑肌瘤的CT及MRI表现.2例均行MRI平扫及增强,1例行MRI动态增强,1例行CT平扫.结果 2例均位于右侧鞍旁.例1行CT平扫示中颅窝鞍旁类圆形稍高密度肿块,密度均匀,周围未见水肿,MRI平扫T1WI呈低信号,扩散加权成像(DWI)呈低信号,T2WI呈不均高信号,内可见条状低信号.病灶周围见薄层环状水肿带,增强扫描肿块明显均匀强化,局部可见脑膜尾征;例2 MRI平扫示鞍旁卵圆形肿块,T1WI呈等信号,T2WI呈高信号,右三叉神经受压,增强扫描早期示病灶中心斑片状强化,增强晚期示病灶逐渐从中心向周边强化.结论 动态增强扫描呈中心性渐进性强化可能为颅内血管平滑肌瘤特征性表现,有助于其诊断与鉴别诊断.     

胰腺结核的CT及MRI诊断

目的 :探讨胰腺结核的CT及MRI表现,提高对胰腺结核的诊断水平。方法 :回顾性分析经病理证实及临床抗结核治疗病灶缩小确诊的胰腺结核患者6例,均行CT平扫及增强扫描,其中4例同时行MRI平扫及增强扫描。结果:CT检查发现胰头部结核性病变6例,平扫呈等或略低密度肿块,增强扫描后病灶呈轻度及中度不均匀性强化或呈环形强化;4例行MRI检查T1WI病灶呈等或略低信号,T2WI病灶呈等或略高信号,内见片状高信号,增强扫描后呈轻度强化2例,环状强化2例。结论:胰腺结核的CT及MRI表现为胰头部局灶性实质性或囊实性病灶,增强扫描后呈轻中度强化或蜂窝状环形强化,伴有胰周淋巴结或腹腔淋巴结肿大环状强化,可合并脾脏等腹腔结核灶,影像学表现有一定特异性。     

亚急性坏死性脑脊髓病的磁共振成像

目的:探讨磁共振成像(MRI)对亚急性坏死性脑脊髓病的诊断价值。方法:收集我院确诊为亚急性坏死性脑脊髓病患者6例,回顾性分析其MRI表现。结果:6例患者均出现双侧豆状核对称性异常信号,T1WI呈低信号,T2WI呈高信号,T2-FLAIR呈混杂信号,无占位效应,增强扫描病灶无强化。结论:亚急性坏死性脑脊髓病最常累及双侧豆状核,其MRI表现具有特征性,结合临床容易诊断。     

脑内基底节区对称性低密度或异常信号的发病机理及CT-MR诊断

目的：分析基底节区对称性低密度或异常信号的发病机理，加深对其CT-MRI表现的认识。方法：30例病人均行CT及MRI横轴位扫描。结果：CT平扫均表现为两侧基底节区的对称性低密度，MRI T1WI呈对称性低信号，T2WI呈高信号。结论：MRI能更多地显示受累的部位，同时了解具有以上CT-MRI表现的疾病范畴，对于鉴别诊断具有重要意义。     

颅内血管平滑肌瘤的影像表现(附2例讨论)

目的探讨颅内血管平滑肌瘤的CT及MRI表现。资料与方法结合文献回顾性分析2例经手术病理证实的位于颅内鞍旁的血管平滑肌瘤的CT及MRI表现。2例均行MRI平扫及增强,1例行MRI动态增强,1例行CT平扫。结果 2例均位于右侧鞍旁。例1行CT平扫示中颅窝鞍旁类圆形稍高密度肿块,密度均匀,周围未见水肿,MRI平扫T1WI呈低信号,扩散加权成像(DWI)呈低信号,T2WI呈不均高信号,内可见条状低信号。病灶周围见薄层环状水肿带,增强扫描肿块明显均匀强化,局部可见脑膜尾征;例2 MRI平扫示鞍旁卵圆形肿块,T1WI呈等信号,T2WI呈高信号,右三叉神经受压,增强扫描早期示病灶中心斑片状强化,增强晚期示病灶逐渐从中心向周边强化。结论动态增强扫描呈中心性渐进性强化可能为颅内血管平滑肌瘤特征性表现,有助于其诊断与鉴别诊断。     

CT、MRI与DSA在脑内型海绵状血管瘤诊断中的价值

目的探讨CT、MRI与DSA检查在脑内型海绵状血管瘤诊断中的价值。资料与方法回顾性分析经手术病理证实的22例脑内型海绵状血管瘤患者资料,CT平扫22例,其中增强扫描17例。MRI检查22例,其中增强扫描13例。DSA检查5例。结果CT表现为高密度,略高密度,等密度。MRI表现为T1WI呈等或略低信号、T2WI呈高信号;T1WI与T2WI均呈高信号,病灶周围可见低信号环;T1WI与T2WI均呈低信号。病灶无占位效应或占位效应轻微,病灶多为不强化及轻微强化。DSA检查无肿瘤染色。结论脑内型海绵状血管瘤MRI表现典型,比CT表现更具特异性,与CT检查结合是诊断脑内型海绵状血管瘤的有效方法,参考DSA表现有利于脑内型海绵状血管瘤的诊断。     

软组织海绵状血管瘤的MRI诊断

目的探讨软组织海绵状血管瘤的MRI表现及其诊断价值。方法回顾性分析35例软组织海绵状血管瘤患者的影像资料,全部患者均有MRI平扫和增强扫描,12例有X线平片检查,10例有CT检查。结果单发病灶31例,2~4个多发病灶者4例,共检出43个病灶。SE序列T1WI上33个病灶呈中等略高信号,T2WI上全部病灶呈高信号,信号不均匀。33个病灶内及周边可见高信号的病变,Flash2d序列21个病灶T1WI上高信号被抑制,12个病灶内T1WI上高信号未被抑制。Gd-DTPA增强扫描39个病灶呈明显强化,但强化不甚均匀,其内可见点条状不强化影。结论软组织海绵状血管瘤在MRI表现上有一定特征性,MRI对诊断软组织海绵状血管瘤有重要价值。     

颅骨转移性病变的MRI诊断

目的：探讨MRI对颅骨转移性病变的诊断及临床价值,分析各MRI序列的诊断价值。方法：回顾性分析17例经病理证实的颅骨转移性病变的病例资料,其中原发肿瘤为肺癌11例,白血病2例,前列腺癌2例,乳腺癌1例,直肠癌1例。17例均行MRI检查,其中平扫5例,直接增强4例,同时行平扫及增强8例,其中5例行ECT骨扫描,9例行CT平扫。MRI的主要序列有矢状面和轴面T1WI、T2WI及增强扫描。结果：17例中单发颅骨转移3例,多发颅骨转移14例,本组转移病灶的好发部位依次为颞骨、顶骨、枕骨、额骨等,合并颅内脑实质转移15例。9例兼行MR和CT的患者中,在MRI上2例发现了更多的颅骨病灶,3例检出了颅内病灶;5例兼行MR和ECT的患者中,所有颅骨及颅内的病灶的细节在MR上显示更清晰。颅骨转移的MRI主要表现为局灶性溶骨性病灶呈长T1、长T2信号或成骨性病灶呈长T1、短T2信号,13例平扫MR中,10例在T1WI上的信号均较T2WI上明显;病灶可侵及颅骨内外板以及脑膜,呈新月状或双凸形影,12例行增强扫描病例均强化明显。结论：MRI对颅骨转移的具有极高的诊断价值,可发现细微的病灶,T1WI和增强扫描是有价值的扫描序列。     

肝脏炎性肌纤维母细胞瘤组织学分型与CT、MRI对比分析(附19例报告)

目的 探讨肝脏炎性肌纤维母细胞瘤(HIMT)CT、MRI特征与病理改变的关系,提高对其的诊断准确率.资料与方法 经手术及病理证实的HIMT患者19例,其中男12例,女7例,年龄27～79岁,平均46.7岁.18例行CT平扫及增强扫描;1例仅行CT平扫,7例同时行CT、MRI平扫及增强扫描.结果 19例中15例为单发病灶,4例多发,共26个病灶,位于肝左叶4个,肝右叶22个.组织学分型包括黄色肉芽肿型15例:CT平扫低密度12例,等密度3例;14例增强扫描,动脉期1例明显强化,门静脉期轻度强化10例,平衡期轻度强化4例.4例行MRI检查,T1WI呈等信号1例,低信号3例,T2WI均为高信号.增强扫描4例动脉期均无强化,门静脉期或平衡期轻度强化.浆细胞肉芽肿型3例:CT平扫呈稍低密度2例,等密度1例.增强扫描动脉期均无强化,门静脉期或平衡期轻度强化;行MRI检查2例,增强扫描呈壁结节强化.硬化型1例:CT平扫为等、低混杂密度影,增强扫描动脉期无强化,门静脉期呈均匀强化,平衡期病灶密度减低.MRI平扫T1WI为等信号,T2WI为高信号,增强扫描动脉期无强化,门静脉期轻度强化,延迟期强化明显.26个病灶中4个有假包膜.结论 CT及MRI平扫及增强扫描能够反映HIMT组织学变化特点,但对不同类型病变的CT、MRI鉴别诊断仍比较困难.     

Value of diffusion-weighted imaging in central pontine and extrapontine myelinolysis

Introduction

Central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) are rare neurological disorders characterized by demyelination in and/or outside the pons. Whether diffusion-weighted imaging (DWI) might facilitate an earlier diagnosis has not yet been studied systematically.

Methods

We describe demographics, clinical presentation, and early magnetic resonance imaging (MRI) findings with special emphasis on the relevance for diagnosis of CPM and/or EPM in eight patients.

Results

Of the analysed eight patients (aged 37–70 years; two men, six women), CPM was diagnosed in three, EPM in one, and a combination of CPM and EPM in four patients. Aetiology was rapid correction of sodium in two patients; a combination of hyponatremia, alcoholism and alcohol withdrawal in five patients and unclear in one patient. Seven patients suffered from chronic alcoholism and four from malnutrition. Demyelinating lesions were found in the pons, thalamus, caudate nucleus, putamen and midbrain. While the lesions could be clearly delineated on T2- and T1-weighted images, DWI demonstrated a strong signal in only six patients. Furthermore, DWI demonstrated lesions only to some extent in two patients and was completely negative in two patients on initial MRI. In none of the patients did the demonstration of hyperintense lesions on DWI precede detection on conventional MRI sequences. Apparent diffusion coefficient (ADC) values were heterogenous with a decrease in two cases and an increase in the remainder.

Conclusions

We conclude that early DWI changes are a common finding in CPM/EPM but do not regularly precede tissue changes detectable on conventional MRI sequences. Heterogenous ADC values possibly represent different stages of disease.     

颅内动静脉瘘的CT和MRI诊断价值

目的:探讨CT和MRI对颅内动静脉瘘的诊断价值。方法:回顾性分析18例颅内动静脉瘘的CT和MRI表现。18例均经DSA检查明确诊断。其中12例行CT检查;16例行MRI检查,同期6例行MRA检查。结果:颅内动静脉瘘的CT和MRI的特征性表现为脑沟、脑裂、基底池内血管影增粗、增多,呈散在分布,受累及的静脉窦增粗,且病变区没有畸形血管团。海绵窦硬脑膜动静脉瘘在T2WI上表现为局部流空信号增宽,MRA原始图像显示局部有较丰富的异常纤细血流信号。结论:认识颅内动静脉瘘的CT和MRI表现,有助于早期诊断及治疗。MRI对显示软脑膜血管扩张优于CT。选择性脑血管造影是确诊本病的可靠手段。     

椎管内神经鞘瘤的低场MRI诊断

目的:探讨椎管内神经鞘瘤的低场MRI表现及诊断价值。方法:搜集12例经手术病理证实的椎管内神经鞘瘤,重点分析其MRI特点及发病部位。结果:本组病例肿瘤均为单发,T1WI肿瘤呈低或等信号,T2WI呈高信号,增强后显著强化,12例肿瘤病理均无钙化。MRI对椎管内神经鞘瘤定位诊断符合率100%,定性诊断符合率83.3%。结论:低场MRI可作为诊断椎管内神经鞘瘤的敏感检查方法,正确认识其MRI征象能帮助术前诊断,并指导手术。     

儿童肝脏局灶性结节增生临床表现与影像学表现关联分析

目的：探讨儿童肝脏局灶性结节增生（FNH）的影像表现,提高对该病影像学特征的认识。方法：回顾性分析6例经病理证实为 FNH 的患儿临床及影像学资料,其中3例患儿发病前确诊患有神经母细胞瘤、急性淋巴细胞白血病和髓母细胞瘤,另外3例患儿无恶性病变病史,均系偶然发现。3例患儿行 MRI 检查,2例患儿行 CT 检查,1例患者行 CT及 MRI 检查,行 CT 检查者全部行增强扫描,2例行 MRI 增强扫描。结果：6例诊断为 FNH 患儿中3例（男2例,女1例,平均年龄8．7岁）存在远隔脏器恶性病变病史,影像学上3例患儿肝脏均呈多发病变,病变最大径2．0～5．2 cm,边界尚清楚,1例可见纤维分隔及中心瘢痕,1例可见引流静脉。其他3例 FNH 患儿（男1例,女2例,平均年龄7．3岁）无恶性病变病史,2例呈单发病变,1例呈多发病变;病变最大径4．3～7．6 cm,边界清楚,2例可见纤维分隔及中心瘢痕,3例均无明确引流静脉显示。结论：增强 CT 及 MRI 检查,尤其是 MSCT 血管成像能真实反映儿童 FNH 的病理学特点及血液动力学改变,对儿童肝脏 FNH 患者影像学特点的认知和了解对于该病的鉴别诊断及临床治疗具有重要意义。     

LAVA多期动态增强扫描在前列腺癌诊断中的价值

目的：探讨常规MRI及肝脏客积超快速三维成像（LAVA）序列多期动态增强扫描对前列腺癌的诊断价值,提高对前列腺癌的诊断准确性。方法：回顾性分析经穿刺活检和手术病理证实的60例前列腺占位的MRI表现,其中59例为前列腺癌,1例为前列腺增生。将所有病例分为2组：LAVA组30例,采用常规MRI平扫结合LAVA多期动态增强扫描;对照组30例,采用常规MRI平扫和增强扫描。结果：LAVA组30例患者中,术前诊断为前列腺癌27例（诊断符合率为90％）,不确定诊断2侧,前列腺增生1例。对照组30例中MRI诊断前列腺癌20例（符合率为69％）,不确定诊断4例,前列腺增生5例,1例前列腺增生误诊为前列腺癌并且漏诊了膀胱癌。LAVA组和对照组诊断符合率的差异有显著性意义（P〈0．05）。结论：LAVA多期动态增强扫描对前列腺癌具有重要诊断价值。     

Aggressive fibromatosis: MRI features with pathologic correlation

OBJECTIVE: We present the MRI features with pathologic correlation of aggressive fibromatosis, incorporating 203 cases over a 5-year period from the Royal Marsden Hospital Sarcoma Unit database. MATERIALS AND METHODS: Sixty patients had imaging available for retrospective review of which 29 had preoperative MRI and final histopathologic diagnosis of aggressive fibromatosis. RESULTS: The average age at diagnosis was 41.3 years with a female-to-male sex ratio of 1.2:1. Twenty lesions were extraabdominal; six, intraabdominal; and three, in the abdominal wall (classic desmoid). The average tumor size was 6.4 cm (range, 2.2-13.7 cm). Intraabdominal aggressive fibromatosis produced the largest tumors, averaging 9.5 cm. Most lesions were ovoid (52%) or infiltrative (34.5%) in outline with an irregular or lobulated contour (76%). The lesions crossed major fascial boundaries in 31% of cases overall and in 66% of patients referred for recurrent disease. On MRI, homogeneous isointensity or mild hyperintensity on T1-weighted images and heterogenous high signal on T2-weighted or STIR images were seen. All lesions enhanced after IV gadolinium, usually avidly. In contrast to previous reports, 38% of cases failed to show low signal on all pulse sequences and no abnormalities were seen in local bone structures. Histology showed sheets of bland spindle cells in dense collagen and did not vary with the MRI signal characteristics of the lesion. Patients referred for recurrent disease were most likely to have a recurrence after surgery. MRI and pathology findings did not predict recurrence. CONCLUSION: Accurate diagnosis and staging of aggressive fibromatosis by MRI have important treatment and prognostic implications.     

髓母细胞瘤的MRI诊断及临床分析

目的:分析髓母细胞瘤的临床特点、磁共振成像(MRI)征象及其诊断价值。方法:收集经手术与病理证实的髓母细胞瘤4 6例,全部病例均行MRI检查。结果:髓母细胞瘤主要临床表现为头痛、恶性、呕吐及行走不稳。肿瘤位于小脑蚓部4 2例,小脑半球4例。MRI上,病灶在T1WI为低信号者占81% (33/ 4 6 ) ,混杂信号者占19% (13/ 4 6 ) ;T2 WI上为高信号者81% (33/ 4 6 ) ,混杂信号者占19% (13/ 4 6 ) ;Gd DTPA增强扫描显示病灶呈均匀强化者占75 % (34/ 4 6 ) ,不均匀强化者占2 0 % (9/ 4 6 ) ,有5 % (3/ 4 6 )的病灶显示环状强化,瘤周有不同程度的水肿及伴有不同程度脑积水表现。MRI对髓母细胞瘤检出率、定位及定性诊断正确率分别为10 0 %、96 %、90 %。结论:髓母细胞瘤的MRI表现具有一定特征性。MRI检查多方位、多序列成像,对其诊断、治疗及术后随访等有重要作用,因此髓母细胞瘤的检查应首选MRI。     

Alveolar echinococcosis of the liver: correlative color Doppler US, CT, and MRI study

Purpose: To determine and compare the imaging features of hepatic alveolar Echinococcosis using color Doppler US, CT, and MRI.

Material and Methods: Abdominal CT and MRI with and without contrast agents and color Doppler US were performed on seven patients with hepatic alveolar Echinococcosis. The lesions were evaluated for location, features of echogenicity, intensity and density, calcification, and vascular, hilar, and perihepatic involvement. The diagnosis was confirmed histopathologically in all patients.

Results: Six patients had solitary lesions, and one displayed multiple lesions. The lesions were generally seen as heterogeneous and hyper- or hypoechoic when imaged with color Doppler US, hypodense with CT, and hypointense with MRI, in comparison with the liver parenchyma. Calcification, central necrosis, and small peripheral cysts were observed in six, seven, and four patients, respectively. Vascular flow or contrast enhancement was not observed in any of the cases. A look at the respective advantages of each method reveals that calcification was best rendered visible via CT, small peripheral cysts with T2-weighted MRI, central necrosis with CT and MRI, and perihepatic invasion with multiplanar MRI. Vascular involvement was revealed by all methods.

Conclusion: Color Doppler US, CT, and MR imaging function extremely well as complementary methods in the diagnosis of HAE. Color Doppler US should be performed in these patients owing to its ability to efficiently detect the disease. Knowledge of imaging characteristics makes it possible to radiologically ascertain an early diagnosis.     

结节性硬化的影像诊断

目的:探讨结节性硬化的CT和MRI影像学特征表现。方法:回顾性分析10例结节性硬化的CT和MRI表现,10例均行头部CT平扫,CT增强1例,膝关节CT平扫1例,2例行头部MRI平扫。结果:CT表现中,所有病例均见双侧侧脑室室管膜下多发高密度钙化结节,1例并有室管膜下巨细胞星形细胞瘤,1例有皮肤血管纤维瘤。2例MRI均见双侧侧脑室室管膜下多发结节,T1WI呈稍高信号或等信号,T2WI则为低信号。结论:CT和MRI检查对结节性硬化的诊断具有重要价值,其CT和MRI影像学表现具有特征性。     

淋巴管瘤的磁共振成像诊断

目的:探讨淋巴管瘤不同病理学类型的磁共振表现特点以及鉴别诊断.方法:回顾性分析44例经手术病理证实为淋巴管瘤的MRI检查资料,所有病例均行矢、冠、轴三平面扫描,其中30例于MRI平扫后行常规增强扫描.以病理学所见为参照,分析各病理类型淋巴管瘤的MRI表现特点并统计分析不同病珲类型淋巴管瘤发生部位的差异.MRI征象分析包括:病变的形态、累及范围、有尤包绕血管、内部信号特点、有尤分房、分隔厚薄情况及强化特征.结果:MRI上淋巴管瘤的形态多为不规则状(38/44),边界不清(30/44),部分见血管包绕征(17/44).较大者产生占位效应.小同病理类型的淋巴管瘤发生部位的差异无显著性.与邻近肌肉组织相比,24个(54.5%)病变表现为T<1'>WI上等或高信号、T2WI上更高信号区,较具特征.囊状淋巴管瘤31例,病变内可见液-液平面,分房大,分隔细、薄,增强扫描旱轻度或无强化;海绵状淋巴管瘤7例,表现为分房多,大小不一,分隔厚或有乳头状突起,增强扫描显示分隔及乳头明显强化;血管淋巴管瘤6例,MR表现为分房大小不一,分隔厚薄不一,内未见液-液平面,增强扫描囊壁及分隔明显强化,难与海绵状淋巴管瘤鉴别.结论:淋巴管瘤不同病理学类型的MRI表现有一定特点,MRl对于鉴别囊状淋巴管瘤与其他两类较具价值,而海绵状淋巴管瘤有时难以与血管淋巴管瘤鉴别.