儿童脑性偏瘫的CT诊断研究

目的：研究儿童脑性偏瘫的ＣＴ形态学改变。材料和方法：对７２例临床诊断为脑性偏瘫的患儿进行ＣＴ检查，并对其ＣＴ表现进行回顾性分析。结果：７２例中，ＣＴ异常６３例，ＣＴ阳性率为８７．５％。ＣＴ表现可分成五种不同的类型：（１）脑发育畸形（１１．１％），反映出生前大脑的发育障碍；（２）脑室周萎缩（３８．９％），与早产儿缺血缺氧性脑损害有关；（３）皮质或皮质下软化（２２．２％）；（４）混合型（１５．３％）；（５）正常（１２．５％）。结论：ＣＴ表现及分类反映了不同脑发育阶段脑损害的病理特点，ＣＴ形态学研究对脑性偏瘫的病因学诊断及预后判断有重要价值。     

小肝细胞癌的CT诊断

对１１８例经手术病理证实的小肝细胞癌（ＳＨＣＣ）进行了前瞻性ＣＴ研究。男１０９例，女９例，年龄１８～７６岁，平均４９．５岁。１１８例均作了增强前和增强后扫描。其中２０例还加进床／同层动态团注增强ＣＴ（ＤＬＢ一ＣＴ、ＤＳＢ一ＣＴ），５例作了４ｈ延迟ＣＴ（Ｄ一ＣＴ），１２例作了动脉造影ＣＴ（ＣＴＡ），其中５例又加作了经动脉门脉造影ＣＴ（ＣＴＡＰ）。增强前ＳＨＣＣ主要表现为低密度（９３．２％）。增强后动脉期呈明显早期增强，但密度很快下降，在门脉期呈低密度表现。在Ｄ一ＣＴ和ＣＴＡＰ图像上呈低密度，而ＣＴＡ为显著高密度。不同ＣＴ方法检出ＳＨＣＣ敏感的排列顺序为：增强前ＣＴ＜增强后ＣＴ＜ＤＩＢ一ＣＴ或Ｄ－ＣＴ＜ＣＴＡ或ＣＴＡＰ。     

肾母细胞瘤的 CT 表现及其病理基础(附21例分析)

目的：探讨肾母细胞瘤的ＣＴ表现及其病理基础。方法：分析２１例病理证实的肾母细胞瘤的ＣＴ表现及病理联系。结果：２０例（９５．２％）单侧发病，１２例（５７．１％）瘤体呈圆形或类圆形，直经平均约１０ｃｍ，平扫ＣＴ值１８～４５ＨＵ，内可见斑状更低密度区，病理基础为出血、坏死及瘤性脂肪；１２例（５７．１％）边缘较清，为肿瘤压迫周围正常肾组织所致，增强尤著：１６例（７６．１％）瘤体占据肾实质大部；５例（２３．８％）可见斑点状或孤形钙化。结论：幼儿单侧或双侧肾实质较大低密度肿块内含更低密度区或钙化应首先考虑肾母细胞瘤。     

婴儿晚发性维生素K缺乏致颅内出血的CT诊断

目的：分析婴儿晚发性维生素Ｋ缺乏致颅内出血的ＣＴ表现和诊断价值。材料和方法：对经临床确诊的２５例婴儿晚发性维生素Ｋ缺乏致颅内出血的ＣＴ资料进行回顾性分析，着重观察出血部位特征。全部病例均为平扫。结果：颅内出血的ＣＴ表现为：１多部位混合性出血：蛛网膜下腔出血（２３／２５），硬膜下出血（１７／２５），脑实质出血（１２／２５）。２伴发脑水肿（１９／２５），脑疝（１２／２５）和对侧侧脑室扩大（４／２５）。结论：婴儿晚发性维生素Ｋ缺乏致颅内出血的ＣＴ表现有一定特征性，ＣＴ能起到定位定性的作用。     

电子束CT急性胰腺炎的实验研究

目的：研究急性胰腺炎不同胰腺病变区ＣＴ“时间－密度曲线”（Ｔ—Ｄ曲线）特征对各病变区作定性和定量诊断的作用。材料和方法：采用电子束ＣＴ（ＥＢＣＴ）Ｆｌｏｗ扫描程序扫描５条急性胰腺炎模型犬的胰腺正常区、水肿区和坏死区各１２个、１３个和１２个，对照病理分析所获得的Ｔ—Ｄ曲线和相应的ＣＴ值。结果：实验犬胰腺正常区、水肿区和坏死区Ｔ—Ｄ曲线的特征分别表现为“尖峰型”、“斜坡型”和“平坦型”。结论：通过辨认不同病变区Ｔ—Ｄ曲线特征可对急性胰腺炎作精确的定性和定量诊断     

螺旋CT门静脉造影的临床应用

目的 探讨螺旋ＣＴ门静脉造影（ＣＴＰ）对门静脉系统的显示能力,评价其在该系统的临床应用价值。方法 １６０例 颖有肝脏疾病的患者进行了ＣＴＰ检查,其中经手术治疗者４７例,常规血管造影者１２例,以此为对照,对肝脏肿瘤定位及门静脉癌栓、门脉高压侧支循环的显示情况和不同疾病的ＣＴＰ表现做一分析。结果 ＣＴＰ能清晰成像门静脉系统,精确定位肝内病灶（１００％）。ＣＴＰ原始图像的ＣＴＰ表现做一分析。结果 ＣＴＰ     

新生儿颅内出血的CT特征

研究新生儿颅内出血的ＣＴ特征性表现。对４８例新生儿颅内出血的ＣＴ表现进行了回顾性分析，并对１７例进行了追踪观察。蛛网膜下腔出血２９例，脑实质出血２例，脑室管膜下出血１例，脑室出血４例，混合型脑出血１２例。（１）ＳＡＨ为新生颅内出血最常见的类型约占６０％，仅表现为直窦高密度者，确定超过５ｍｍ为诊断标准，并根据其形态特征分为前窄后宽，前宽后窄和全长增宽３种类型；（２）ＳＥＨ见于早产儿，ＣＴ诊断较困难。     

涎腺区肿块的CT诊断

目的：探讨涎腺区病变的ＣＴ诊断价值。方法：回顾性总结经手术病理证实的３４例涎腺区肿块的临床与ＣＴ资料，对其ＣＴ表现进行了分析。结果：３４例中有２６例术前ＣＴ准确诊断，诊断符合率７３．５％，腮腺区２４例，颌下腺区１０例。良性肿块的ＣＴ表现：结节状（１３例），分叶状（５例），不规则形（３例）。大多数肿块边缘光滑，边界清晰，密度均匀。病理对照：有完整包膜１８例，无完整包膜３例。恶性肿块ＣＴ表现呈不规则形（１３例），边缘毛糙，与周围正常组织分界不清。病理对照：肿块多数无包膜（１１例）。结论：涎腺ＣＴ扫描的最大优势在于定位准确，能明确病变的范围及其与周围组织的关系，同时可根据肿块的形态及密度较好地鉴别其性质。     

后颅窝囊肿的CT－MR影像学

目的：本文目的是对后颅窝囊肿的ＣＴ－ＭＲ影像学的诊断作用进行评价。材料与方法：１２例后颅窝囊肿的ＣＴ和ＭＲ影像表现进行了分析，探讨了其与临床表现和类型的相关性。结果：本组病例包含Ｄａｎｄｙ－Ｗａｌｋｅｒ囊肿（５例）、蛛网膜囊肿（３例）和巨枕大池（４例），ＣＴ和ＭＲ都可提供无创性检测手段。结论：ＣＴ和ＭＲ二者对后颅窝囊肿的诊断均有效，但在显示病变的性状、大小和轮廓方面，ＭＲ比ＣＴ稍胜一筹     

后颅窝囊肿的CT—MR影像学

目的：本文目的是对后颅窝囊肿的ＣＴ－ＭＲ影像学的诊断作用进行评价。材料与方法：１２例后颅窝囊肿的ＣＴ和ＭＲ影像表现进行了分析，探讨了其与临床表现和类型的相关性。结果：本组病例包含Ｄａｎｄｙ－Ｗａｌｋｅｒ囊肿（５例）、蛛网膜囊肿（３例）和巨枕大池（４例），ＣＴ和ＭＲ都可提供无创性检测手段。结论：ＣＴ和ＭＲ二者对后颅窝囊肿的诊断均有效，但在显示病变的性状、大小和轮廓方面，ＭＲ比ＣＴ稍胜一筹。     

70例急性酒精性肝炎的CT影像分析

目的：探讨急性酒精性肝炎的CT影像特征。方法：回顾性分析经临床、化验、CT综合诊断的70例急性酒精性肝炎病例的CT影像资料;本组病例肝功能化验均无甲、乙肝炎表现。结果：急性酒精性肝炎CT影像表现为：点状、片状低密度急性肝损害征象以及胆汁淤积、肝内胆管扩张,重者可出现肝组织坏死液化、肝肿大。急性酒精性肝炎的并发症有：肝硬化、脾大、脂肪肝、腹水。根据急性肝损害的严重程度,分为轻度39例,中度23例,重度8例。治疗后复查CT,除2例死亡外,其他所有病例的急性肝损害征象可恢复。其并发症酒精性肝硬化为不可逆病变。结论：CT能够显示急性酒精性肝炎的影像学特征。     

急性胰腺炎合并肝脏低密度改变的CT诊断

目的：通过对急性胰腺炎合并的肝脏低密度改变的CT表现进行分析,探讨其变化规律及可能的发生机理。方法：回顾分析资料完整的62例急性胰腺炎患者的肝脏CT表现,采用16层螺旋CT机,重建层厚为5mm。结果：62例患者中,42例CT显示肝脏低密度改变,占67.74%（42/62）;在2～20天复查CT,有61.90%（26/42）病例随病情的好转而减轻,其中45.24%（19/42）病例完全恢复为正常肝实质密度,CT值高于脾脏。最早恢复时间为发病后第5天即恢复正常。38.09%（16/42）病例无恢复。结论：多层螺旋CT特别是16层螺旋CT在清楚显示急性胰腺炎胰腺本身及其周围变化的同时亦可对继发性的肝脏低密度改变及其转归做出确切的评判,为急性胰腺炎的早期诊断增添了新的依据;结合文献认为急性胰腺炎的肝脏低密度改变主要是急性脂肪肝的形成造成的。     

弥漫型脂肪肝内局灶性病变的CT诊断

目的 研究在弥漫型脂肪肝背景下肝局灶性病变的CT特征,以提高对其诊断的准确率.资料与方法 回顾性分析40例弥漫型脂肪肝合并局灶性病变(35例)或残存肝岛(5例)患者的CT资料,观察脂肪肝对肝局灶性病变CT表现的影响.结果 40例弥漫型脂肪肝中,26例合并多发局灶性肝病变,9例合并单发病变,5例残存肝岛. 35例肝局灶性病变中,转移瘤18例 ,肝细胞癌(HCC)术后复发2例,血管瘤8例,多发囊肿5例,多发腺瘤及单发局灶性结节增生(FNH)各1例.CT平扫肝局灶性病变相对密度随脂肪肝程度而异,边界多不清,增强后强化方式则与无脂肪肝背景的肝内病变相似.结论 弥漫型脂肪肝内局灶性病变,其CT表现与正常背景下有所差异,增强检查尤其是动态增强对病变的诊断与鉴别具有重要意义;对不典型病例,随访对比有助于正确诊断.     

CT and MR imaging of postnecrotic liver scars

Four cases of postnecrotic liver scar were examined by dynamic CT or MR imaging or both. Postnecrotic scars appeared as low-density areas on plain CT, showed marked and prolonged enhancement on single level dynamic CT, and became isodense on postcontrast scan. On T2-weighted images, postnecrotic scar were as hyperintense as the spleen. Postnecrotic liver scar is an example of localized attenuation or intensity difference not corresponding to mass lesion. It should be distinguished from mass lesions associated with lobar or segmental attenuation (or intensity) difference of the liver as well as nonmass lesions such as irregular fatty infiltration, radiation hepatitis, and hepatic infarction.     

Imaging features of perivascular fatty infiltration of the liver: initial observations

PURPOSE: To retrospectively identify and describe the imaging features that represent perivascular fatty infiltration of the liver. MATERIALS AND METHODS: The institutional review board approved the study and waived informed consent. The study complied with the Health Insurance Portability and Accountability Act. Ten patients (seven women, three men; mean age, 78 years; range, 31-78 years) with fatty infiltration surrounding hepatic veins and/or portal tracts were retrospectively identified by searching the abdominal imaging teaching file of an academic hospital. The patients' medical records were reviewed by one author. Computed tomographic (CT), magnetic resonance (MR), and ultrasonographic (US) imaging studies were reviewed by three radiologists in consensus. Fatty infiltration of the liver on CT images was defined as absolute attenuation less than 40 HU without mass effect and, if unenhanced images were available, as relative attenuation at least 10 HU less than that of the spleen; on gradient-echo MR images, it was defined as signal loss on opposed-phase images compared with in-phase images; and on US images, it was defined as hyperechogenicity of liver relative to kidney, ultrasound beam attenuation, and poor visualization of intrahepatic structures. Perivascular fatty infiltration of the liver was defined as a clear predisposition to fat accumulation around hepatic veins and/or portal tracts. For multiphase CT images, the contrast-to-noise ratio was calculated for comparison of spared liver with fatty liver in each imaging phase. RESULTS: Fatty infiltration surrounded hepatic veins in three, portal tracts in five, and both hepatic veins and portal tracts in two patients. Six of the 10 patients had alcoholic cirrhosis, two reported regular alcohol consumption (one of whom had acquired immunodeficiency syndrome and hepatitis B), one was positive for human immunodeficiency virus, and one had no risk factors for fatty infiltration of the liver. In three of the 10 patients, fatty infiltration was misdiagnosed as vascular or neoplastic disease on initial CT images but was correctly diagnosed on MR images. CONCLUSION: Perivascular fatty infiltration of the liver has imaging features that allow its recognition.     

Value of dual-energy CT in differentiating focal fatty infiltration of the liver from low-density masses

Focal (irregular, partial) fatty infiltration of the liver may simulate neoplastic or other hypodense masses on CT. On the basis of previous observations of the phenomenon that differences in X-ray attenuation diminish with increasing energy of X-rays used, we performed a preliminary study to determine if dual-energy CT could be used to discriminate between fatty infiltration and hypodense liver masses. Dual-energy CT at 140 and 80 kVp was performed in 14 patients undergoing liver biopsy and in seven control subjects with presumedly normal liver. Attenuation measurements were taken, and the changes in attenuation between 140 and 80 kVp were calculated. The mean changes in attenuation were 3.5 H for normal liver (n = 7), 2.5 H for hypodense liver masses (n = 6), 13 H for fatty liver (n = 5), 0.3 H for fatty liver combined with hemochromatosis or hemosiderosis (n = 3), and 2 H for the spleen (n = 18). The change in attenuation increased as the fat content in the liver increased. Analysis of variance showed a statistically significant difference (p less than .001) between fatty liver and the other groups. A difference greater than 10 H was unique to fatty infiltration. These results suggest that dual-energy CT may help to differentiate focal fatty infiltration of the liver from low-density neoplastic or other lesions, but only if the iron content of the liver is not increased.     

Fat deposition surrounding intracerebral hemorrhage in a patient suffering from Zieve-syndrome

Summary In a 42-year-old man, admitted a few hours after an acute cerebrovascular event, CT demonstrated a hyperdense hemorrhage surrounded by a hypodense rim similar to perifocal edema or liquefying blood, thus raising doubts about the acuteness of the event. Laboratory findings revealed Zieve-syndrome (alcoholic hyperlipemia, hemolytic anemia, and alcoholic fatty liver) and negative Hounsfield Unit measurement of the hypodense rim finally identified it as a layer of fat around the clot.     

Hepatic steatosis: combined echography-computerized tomography imaging

The authors report their experience with the combined use of US and CT in the study of diffuse and subtotal fatty infiltration of the liver. An apparent disagreement was initially found between the two examinations in the study of fatty infiltration. Fifty-five patients were studied with US and CT of the upper abdomen, as suggested by clinics. US showed normal liver echogenicity in 30 patients and diffuse increased echogenicity (bright liver) in 25 cases. In 5 patients with bright liver, US demonstrated a solitary hypoechoic area, appearing as a "skip area", in the quadrate lobe. In 2 patients with bright liver, the hypoechoic area was seen in the right lobe and exhibited no typical US features of "skip area". Bright liver was quantified by measuring CT density of both liver and spleen. The relative attenuation values of spleen and liver were compared on plain and enhanced CT scans. In 5 cases with a hypoechoic area in the right lobe, CT findings were suggestive of hemangioma. A good correlation was found between bright liver and CT attenuation values, which decrease with increasing fat content of the liver. Moreover, CT attenuation values confirmed US findings in the study of typical "skip areas", by demonstrating normal density--which suggests that CT can characterize normal tissue in atypical "skip areas".     

胰腺脂肪浸润的CT诊断及临床相关性分析

目的:探讨胰腺脂肪浸润的CT诊断价值以及与高血糖、2型糖尿病、高血脂、脂肪肝以及高血压的相关性分析。方法:总结50例胰腺脂肪浸润患者的血糖、血脂值及脂肪肝、高血压的发生情况,设立对照组并与之对比分析。结果:50例胰腺脂肪浸润患者,患者的血糖升高37例、确诊2型糖尿病(T2DM)32例,血脂升高48例,高血压42例、脂肪肝50例。与对照组差别显著(P0.001)。结论:CT能够准确诊断胰腺和肝脏脂肪浸润;胰腺脂肪浸润与高血糖、2型糖尿病、高血压、高血脂、脂肪肝存在高度相关;研究结果能为该类患者临床诊断与治疗提供可靠的依据。     

重度酒精性肝病CT征象治疗前后动态变化对比分析（附6例报告）

目的对比分析重度酒精性肝病CT征象在禁酒及支持治疗前后不同时期的动态变化,以期提高对本病诊断准确性。方法对比分析我院临床及随访证实的6例重度酒精性肝病患者治疗前后CT征象的动态变化,总结其CT特点。结果 CT平扫在普遍密度降低的肝实质内见接近液体密度的更低密度区,部分病灶呈局限性膨隆,有轻度占位效应,酷似占位性病变,增强扫描肝实质呈斑片状不均匀强化,更低密度区周边部分血管及脏器有轻度受压移位现象。禁酒、支持治疗6～9个月等不同时期后复查,病变明显好转,更低密度区及其轻度占位效应减轻或消失,增强扫描趋于均匀强化,血管形态及走行正常。结论酒精性肝病除脂肪肝及肝硬化的表现外,尚有某些酷似占位性病变的CT征象,熟悉这些征象,结合病史及临床随访,对其正确诊断与及时治疗具有重要意义。