肝脏上皮样血管平滑肌脂肪瘤的影像学表现

目的:分析肝脏上皮样血管平滑肌脂肪瘤(HMEA)的影像学表现及其病理,以提高对该病的诊断水平。方法:回顾性分析5例经病理证实的HMEA的影像学表现及其病理。结果:5例均为女性,影像学特征有:①平扫呈低或稍高密度(信号),边缘光整,圆形或类圆形,大小约3.7～9.5cm;②增强扫描动脉期呈较明显或明显均匀强化,少数可不均匀明显强化,中央或周边可见粗大畸形的血管;③强化方式为快进快出或快进慢出、持续性强化,仍有畸形血管可以辨别。结论:HMEA多见于女性,其影像学表现具有一定特征,确诊仍有赖于病理组织学及免疫组织化学检查。     

肝脏上皮样血管平滑肌脂肪瘤的影像诊断

目的分析肝脏上皮样血管平滑肌脂肪瘤(HMEA)的影像学表现及其病理,以提高对该病的诊断水平。方法对4例经手术病理证实为HMEA的临床及影像学资料进行回顾性分析。女性2例,男性2例,年龄22~69岁,平均50.5岁。结果肝脏上皮样血管平滑肌脂肪瘤有其特征性表现:1平扫时多呈低密度圆形或类圆形肿块,边界较清楚;MRI平扫T1WI呈低信号为主,T2WI呈不均匀高信号;2增强扫描动脉期呈较明显或明显强化,少数为不均匀明显强化,肿块内部或边缘可见畸形血管影;3强化方式有快进快出或延迟强化,边缘快进慢出,持续性强化;4病灶强化方式与病理特征关系密切。结论动态增强扫描对于肝脏上皮样血管平滑肌脂肪瘤的术前诊断有重要意义。     

肝脏上皮样血管平滑肌脂肪瘤的影像学表现与病理对照分析

目的探讨肝脏上皮样血管平滑肌脂肪瘤(epithelial angiomyolipomas,EAML)的影像学表现及病理特征,提高对该病诊断的准确性。方法回顾性分析9例经病理证实的肝EAML的临床表现及影像学资料。其中3例行MRI平扫和多时相动态增强扫描,5例行CT平扫和三期动态增强扫描,1例同时行CT和MR检查。9例均误诊,其中6例术前误诊为肝癌,1例误诊为血管瘤,1例误诊为局灶性结节增生(FNH),1例误诊为转移瘤。结果 9例肝EAML均为单发的类圆形肿块,边界清楚;6例位于肝右叶,3例位于肝左叶。CT平扫呈稍低密度;MRI平扫T1WI呈稍低信号,T2WI呈稍高信号;增强扫描动脉期呈明显不均匀强化,少数可均匀明显强化,6例动脉期可见早期引流静脉,8例动脉期或门脉期中央或周边可见明显强化的粗大畸形的血管;强化方式为快进快出或快进慢出。结论 EAML影像学表现具有一定特征性,结合临床资料,对术前正确诊断具有重要意义,但诊断有赖于穿刺活检。     

肾上皮样血管平滑肌脂肪瘤的MSCT表现及误诊原因分析

目的 探讨肾上皮样血管平滑肌脂肪瘤MSCT征象、诊断价值及分析其误诊原因,以提高对该病的术前诊断正确率。方法 选取经手术病理证实但CT检查误诊的12例肾上皮样血管平滑肌脂肪瘤的临床资料、病理及MSCT表现,结合相关文献进行综合分析。结果 本组病例均表现为单发、外突肾轮廓,圆形、类圆形或不规则形肿块,含脂肪3例,呈“楔形征”6例,CT平扫表现为稍高密度9例,等密度2例,稍低密度1例,未见钙化灶;增强后呈“快进快出”3例,“快进慢出”4例,“持续强化”5例,增强后肿瘤内出现粗大血管6例、假包膜2例。误诊为血管平滑肌脂肪瘤3例,肾癌8例,肉瘤1例。结论 肾上皮样血管平滑肌脂肪瘤的MSCT表现有一定特征,当CT平扫表现为不均匀稍高密度,呈“楔形征”,增强后呈“快进快出”、“快进慢出”或“持续强化”,出现粗大瘤内血管时,应考虑上皮样血管平滑肌脂肪瘤可能。     

肝脏上皮样血管平滑肌脂肪瘤的MSCT表现

目的 探讨肝脏上皮样血管平滑肌脂肪瘤(HEAML)的MSCT表现.方法 搜集经手术后病理证实的8例HEAML患者的64层MSCT平扫及双期增强扫描资料,回顾性分析其CT表现,并与病理结果相对照.结果 8例均为女性,7例单发,1例多发.8例CT平扫均呈低密度结节或肿块,未见脂肪密度;增强扫描:7例动脉期明显不均匀强化,病灶内部或边缘见粗大的畸形血管影,强化程度接近腹主动脉,门脉期强化程度低于周围肝实质,呈“快进快出”表现,粗大畸形的血管仍持续强化;1例动脉期全瘤明显强化,门脉期强化程度与正常肝实质相近,呈“快进慢出”表现,病灶周边可见畸形血管影,强化程度低于腹主动脉.7例可见不同程度的引流静脉早期显影.6例可见假包膜,动脉期及门脉期均强化. 结论 HEAML的MSCT表现有一定的特征性,病灶内部或边缘出现粗大畸形的静脉有助于该病的诊断.     

肝脏上皮样血管平滑肌脂肪瘤的影像学诊断

目的 研究肝上皮样血管平滑肌脂肪瘤的影像特征,以减少对该病的误诊.方法 对8例经手术病理证实为肝脏上皮样血管平滑肌脂肪瘤的临床及影像学资料进行回顾性分析.女6例,男2例,年龄56～68岁,平均62.5岁.7例肝上皮样血管平滑肌脂肪瘤行CT平扫及增强扫描,其中1例曾行MRI检查,1例仅行MRI检查.8例均误诊,其中4例术前误诊为肝癌(HCC)和肝血管瘤,3例误诊为局灶性结节增生(FNH),1例误诊为血管肉瘤.结果 肝上皮样血管平滑肌脂肪瘤具有一定特征性的表现:(1)CT、MRI平扫呈等低、低或等高密度(信号),边界光整,圆形或类圆形,大小约5～8 cm;(2)增强扫描动脉期呈明显或较明显均匀强化,少数可不均匀明显强化,中央或周边有明显强化的粗大畸形的血管;(3)强化方式为快进快出或快进慢出、持续性强化,仍有畸形血管可以辨别.结论 影像学结合临床资料对正确诊断肝脏上皮样血管平滑肌脂肪瘤有重要价值,少部分需要进行穿刺活检.     

肝脏血管平滑肌脂肪瘤的影像诊断

目的 研究肝血管平滑肌脂肪瘤的影像特征及其病理基础,以减少对该病的误诊。材料与方法 3例肝血管平滑肌脂肪瘤均经B超和CT平扫及增强扫描,1例加做MRI检查,3例经B超及CT检查显示5个病灶。 2例3个病灶经病理诊断,其中2个病灶术前误诊为肝癌和肝血管瘤;另1例肝脏含脂肪的肿块伴有肾脏多发病变及结节硬化。结果 在影像上肝血管平滑肌脂肪瘤具有特征性的表现：（1）瘤内脂肪,在B超上,表现为强回声区;CT上,呈明显低密度;MR T1WI上呈高信号。（2）肿瘤在肝动脉期明显强化,门静脉期中度强化。结论 肝血管平滑肌脂肪瘤易误诊为其他肝病,但实际上,一些影像学表现能反映肝血管平滑肌脂肪瘤的组织成分,有助于术前正确诊断。     

婴儿型肝脏血管内皮瘤的影像诊断

目的 总结婴儿型肝脏血管内皮细胞瘤的临床与影像学表现. 资料与方法 回顾性分析6例婴儿型肝脏血管内皮细胞瘤的临床与影像学表现,所有的病例均经穿刺病理证实.5例行CT扫描,1例行MRI平扫. 结果 CT平扫表现为肝内低密度灶,1例出现钙化,增强扫描动脉期肿瘤均呈不均匀环形强化,4例中央部位出现结节样强化;门静脉期全部病例由周边向中心强化,强化范围扩大;延迟期病灶密度稍高于或等于正常肝实质.1例MR表现为肝内多发结节,T1WI低信号,T2WI高信号,增强扫描动脉期部分结节呈环形强化,部分结节呈全瘤均匀强化,延迟期全部结节呈全瘤强化. 结论 本病的CT与MRI表现有一定的特征性,有助于诊断本病.     

肝脏上皮样血管平滑肌脂肪瘤的CT和MRI表现特征

目的 探讨肝脏上皮样血管平滑肌脂肪瘤(HEA)的CT、MRI表现特征,旨在提高对该病的认识和诊断准确率.方法 回顾性分析经手术病理证实的8例肝脏HEA患者的CT、MRI资料,其中4例接受CT平扫+增强扫描,2例接受MRI平扫+增强扫描,2例接受CT、MRI平扫+增强扫描.结果 8例患者中,7例为女性,均为单发病灶,病灶最大径42～68 mm,边界均清楚.6例CT表现稍低密度,其中1例可见脂肪密度,2例片状低密度囊变区.4例病灶MRI表现为T1 WI呈稍低信号,1例在反相位可见信号减低,T2 WI呈稍高、高信号.8例增强扫描,7例动脉期明显不均匀强化,5例呈"快进慢出",2例呈"快进快出",1例呈"延迟强化".6例增强扫描见"中心血管征",2例见不完整假包膜.结论 HEA影像表现具有一定特征,动脉期明显不均匀强化、中心血管征、"快进慢出"强化方式及无假包膜表现有助于提示诊断,其确诊仍有赖于组织病理学及免疫组化检查.     

卵巢硬化性间质瘤CT表现与病理对照

目的探讨卵巢硬化性间质瘤(SST)CT影像特征和病理对照,从而提高对SST诊断水平。方法搜集病理证实为SST患者11例,全部病例均行下腹部CT平扫及增强扫描,并对靶病灶进行薄层重建,分析其CT表现。结果 11例SST均为单发,其中右侧7例,左侧4例,CT表现为附件区不规则孤立肿块,边缘尚清,密度欠均匀,9例均为实性,2例为囊实性;增强扫描:9例病灶动脉期呈周边斑片状、结节状明显强化,强化程度与血管相仿,静脉期强化进一步向病灶中心充填,呈"肝脏海绵状血管瘤"样强化;2例病灶动脉期轻中度均匀强化,静脉期持续强化,11例病灶均呈"快进慢出"强化特点,病灶周边见多发迂曲增粗血管影。结论卵巢硬化性间质瘤少见,卵巢硬化性间质瘤CT增强检查多数具有较典型影像学表现,CT检查对其术前诊断有较高价值。     

Stress MR imaging for evaluation of popliteal artery entrapment

The popliteal artery entrapment (PAE) syndrome has been recognized as a cause of arterial occlusion in young people. It is the result of an anomaly of the relationship between the popliteal artery and the gastrocnemius muscle. Eight young healthy volunteers (16 legs) and six patients (10 legs) with suspected PAE underwent magnetic resonance (MR) imaging. Gradient-echo images were obtained in axial planes with the leg at rest and during active plantar flexion against resistance. Imaging at rest allowed identification of PAE signs in only one leg, which had an anomalous medial course of the popliteal artery. In the other cases, only the stress technique was able to show signal loss in the popliteal artery due to muscular compression (two legs) or the presence of accessory muscle slip around the vessel (two legs), as confirmed at surgery. MR imaging is therefore a useful technique for the diagnosis of PAE because of its capability of combining information obtainable with other modalities.     

MR imaging of muscle and tender points in fibromyalgia

Fibromyalgia is a syndrome manifested by chronic, diffuse muscu-loskeletal aching and soreness, palpable muscle tender points, and other symptoms. Standardized clinical diagnostic criteria have recently been developed. Skeletal muscle has been postulated as the end organ in this disease. Biochemical, histologic, electromyographic, and conventional radiographic studies have demonstrated no definitive abnormality. This study sought to establish whether magnetic resonance (MR) imaging could demonstrate any abnormality in these patients. Eighteen patients were entered in the study, 14 of whom were able to complete their examinations. T1 -weighted, T2-weighted, gradient-echo, and STIR (short-tau inversion-recovery) sequences were performed in all patients, with selected patients examined with T1weighted, gadopentetate dimeglu-mine-enhanced sequences. The trapezius and suboccipital regions were imaged in patients who, clinically, had active fibro-myalgia. No abnormalities could be detected. The authors conclude that the conventional MR imaging used in this study was unable to depict any primary skeletal muscle abnormality in fibromyalgia.     

Controversies in cervical spine imaging in trauma patients

No area of emergency radiology has generated as much discussion in recent years as the subject of cervical spine imaging for trauma patients. This review will be in three parts. The first will examine the indications for cervical imaging and will focus on those factors that make patients at high risk or low risk for cervical injury. The second part will discuss the merits of radiography and computed tomography as the main screening diagnostic examination. In addition to the roles of each modality in the evaluation process, such factors as efficacy of diagnosis, time (duration) of study, and cost will be discussed. Finally, the third part will explore the methods currently employed to clear the cervical spine in comatose patients.Presented at the Annual Meeting of the American Society of Emergency Radiology, Las Vegas, Nevada, 22–25 October, 2003     

Uterine contractions: Possible diagnostic pitfall at MR imaging

A total of 206 nongravid patients with various gynecologic problems underwent pelvic magnetic resonance (MR) examinations that included both sagittal T2-weighted and contrast agent–enhanced T1-weighted images. MR images were retrospectively reviewed to identify changes in endometrial configuration on serial images obtained during the same MR examination. In 20 MR examinations (all in women of reproductive age), endometrial distortion due to myometrial bulging was noted on T2-weighted or contrast-enhanced T1-weighted images. It was absent on other MR images obtained at different times. Myometrial bulging exhibited low signal intensity in 18 examinations. The finding resembled adenomyosis or leiomyoma on T2-weighted or contrast-enhanced T1-weighted images. These results evidence the presence of transient myometrial bulging and transient low-intensity myometrium in the nongravid uterus. This phenomenon is thought to represent uterine contraction. Clinicians should be aware of the potential presence of transient low-signal-intensity myometrial bulging that could present diagnostic problems in the normal uterus.     

Brodie Abscess: MR imaging appearance in 10 patients

The magnetic resonance (MR) imaging features of Brodie abscess have not yet been fully evaluated. Ten patients with Brodie abscess, eight of long bone and two of vertebra, were studied with MR imaging. Long bone abscess had a characteristic “target” appearance with four layers: (a) a center with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR (short-inversion-time inversion recovery) images, (b) an inner ring isointense to muscle on T1-weighted images and with high signal intensity on T2-weighted and STIR images, (c) an outer ring hypoin-tense on all images, and (d) a peripheral halo hypointense on T1-weighted images. In six of eight cases, a soft-tissue mass was found. The two vertebral abscesses had a less specific appearance, with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR images. Only the peripheral halo was clearly identified in both cases.     

Right-side aortic arch with aneurysm of aberrant left subclavian artery: MR imaging appearance.

Reports of aneurysms of the subclavian artery in both normal and anomalous aortic arches have been rare. The authors describe a patient with a right-side aortic arch and an aneurysm of the aberrant left subclavian artery, which, to the authors' knowledge, is a previously unreported association. At presentation, the aneurysm appeared as a calcified left superior mediastinal mass. Magnetic resonance imaging enabled preoperative diagnosis and guided surgical planning.     

MR angiography of congenital heart disease: Value of segmented two-dimensional inflow technique and maximum-intensity-projection display

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40–50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65° and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.     

Adrenal tissue characterization with 0.5-T MR imaging: Value of T2*-weighted images

The authors investigated the value of magnetic resonance (MR) imaging at 0.5 T for distinguishing adrenal adenomas from adrenal metastases. The series included 23 adrenal adenomas (18 nonhyperfunctioning, five hyperfunctioning) and 23 adrenal metastases from various organs. Adrenal tumor–liver signal intensity ratios on T1-, T2-, and T2*-weighted images were calculated for adrenal tissue characterization. Adrenal adenomas were more precisely distinguished from adrenal metastases on T2*-weighted images (21 of 23, 91%) than on T2-weighted images (15 of 23, 65%). T1-weighted images were not useful for this distinction. In conclusion, T2*-weighted images were better than routine T2-weighted images for distinguishing adrenal adenomas from adrenal metastases. It can be postulated that the total signal intensity of adrenal adenomas, which contain some fat components, decreased on T2*-weighted images because of an out-of-phase effect.     

MR imaging of silicone gel–filled breast implants in vivo with a method that visualizes silicone selectively

The lack of an adequately sensitive method for detecting silicone leakage and reported serious complications due to silicone leakage were cited as justification by the U.S. Food and Drug Administration for imposing the current restrictions on silicone gel–filled breast prostheses. The authors report a new magnetic resonance imaging method for visualizing silicone leakage: the silicone-only sequence (SOS). The method uses the conventional STIR (short-inversion-time inversion-recovery) technique combined with a 1331 radio-frequency pulse train widely used for water suppression in spectroscopy. With the SOS, silicone can be imaged while signals from fat and water are suppressed. The authors used the SOS to image phantoms and normal and ruptured silicone gel–filled breast prostheses.