基于移动DR X线对急性氯气中毒胸部损伤的动态观察

目的探讨急性氯气中毒的临床及胸部X线表现,动态研究X线表现变化特点,以提高对氯气中毒患者肺部损伤程度的认识水平。资料与方法对28例因氯气中毒患者行动态X线观察,结合临床症状和X线胸片表现进行比较分析。结果28例患者,其中9例胸部正常;2例首诊胸片无异常,1～2天后可见异常。17例首诊可见异常X线表现:两下肺纹理增多3例,两肺内不规则斑点状模糊影6例,两肺散在点状和网格状阴影或肺内大片状浸润,大片状实变影8例;起病1～4天,病变迅速进展8例,其中表现为双肺野呈毛玻璃样并有片状浸润改变3例,弥漫性肺实变5例;治疗7天后,4例恢复正常,2例几乎完全吸收,10例不同程度吸收好转;1例病情反复,好转后又恶化。结论结合临床表现,X线动态观察可反映急性氯气中毒程度及变化特点,为临床诊断和治疗以及预后提供重要的影像学依据。     

胸部闭合性肺实质损伤的影像学表现(附68例报告)

目的 探讨胸部闭合性肺实质损伤的影像学表现.方法 回顾性分析了68例胸部闭合性肺实质损伤患者的影像学资料.结果 胸部闭合性肺实质损伤的影像学表现主要归纳为:①肺挫伤36例,影像学表现为肺纹理增多增粗,伴有斑点状、斑片状密度增高影;大片状密度增高影;磨玻璃样改变;②肺撕裂伤22例,影像学表现为边缘光滑的空洞样团块影;边缘模糊的团片状密度增高影,其内夹杂密度减低区,囊腔内可见气-液平面;③肺血肿10例:表现为圆形或椭圆形团块影,边缘尚清楚,可有分叶,周围略高于中心.肺外表现:血气胸28例、皮下气肿或纵隔气肿15例、单纯性气胸6例.结论 影像学检查是发现、诊断和动态观察胸部闭合性肺实质损伤的最佳方法,典型的肺实质损伤单凭X线平片、CT、外伤史即可诊断,但CT优于X线平片.     

变应性支气管肺曲菌病的X线和CT表现

目的:探讨变应性支气管肺曲菌病(ABPA)患者胸部X线和CT表现。方法:回顾性分析10例经临床确诊的ABPA患者的胸部X线及CT资料。结果:胸部X线表现多种多样,同一个病例可有多种表现:片状及结节状游走性浸润影3例,结节状类似肉芽肿性阴影2例,局限性肺不张2例,支气管柱状或囊状扩张6例,"牙膏样"或树枝样阴影3例。胸部CT表现亦多种多样:中央型支气管扩张并支气管内粘液栓形成6例,其中2例支气管扩张表现为平行的轨道状,1例表象为静脉曲张状,4例支气管内粘液栓表现为结节状高密度影。4例有肺段或肺叶的实变,2例有部分肺不张,2例有肿块影。10例患者上叶均有病灶,其中5例位于右肺上叶。结论:ABPA影像学表现为一过性肺浸润和中心性支气管扩张为主要特点,结合临床表现及实验室检查能提高本病的诊断准确性。     

成人重症甲型H1N1病毒感染性肺炎胸部影像表现

目的 探讨成人重症甲型H1N1病毒感染的胸部影像学表现.方法 回顾性分析12例重症甲型H1N1病毒肺部感染的成人患者的影像表现和临床资料.结果 胸部平片或CT表现为双侧磨玻璃样阴影2例,双侧实变2例,弥漫性磨玻璃样阴影及实变同时存在8例.病灶分布在肺外围6例,既分布在肺外围又分布在中央区域6例.结论 重症甲型H1N1病毒成人患者肺部影像最常见的表现是双肺外围的弥漫性的磨玻璃样阴影和实变.     

急性吸入性汞中毒胸部X线及CT表现

目的 分析急性吸入性汞中毒性肺炎胸部X线及CT表现.方法 23例急性吸入性汞中毒患者,拍摄胸部平片61次,其中11例行胸部CT扫描17次,分析其X线及CT表现.结果 23例入院时X线片示汞毒性实质性肺炎10例,表现为双肺野多发片状密度增高影,边缘模糊,散在分布,3例伴有泡性肺气肿.汞毒性肺间质性炎症7例,表现为肺纹理增重模糊及紊乱,呈斑团状、条索状、网格状致密影.中毒性泡性肺水肿6例,表现为双肺大片状密度增高阴影,4例合并间质性肺水肿,可见K氏A、B线.CT扫描显示汞毒性实质性肺炎为双肺野多发散在分布的片状高密度影,范围广泛,伴发的泡性肺气肿呈低密度大小不等薄壁泡状影.汞毒性肺间质性炎症CT表现为肺纹理增重模糊,局部呈斑团状、条索状、网格状高密度影,病灶周围伴较高密度渗出性改变.中毒性泡性肺水肿表现为双肺大片状或蝶翼状密度增高影,边界模糊、欠光整.结论 急性吸入性汞中毒性肺炎胸部X线及CT表现具有一定的特征性,结合临床病史和实验室检查可作出明确诊断.     

重症及危重症甲型H1N1流感肺炎的影像表现

目的 探讨重症及危重症甲型H1N1流感病毒肺部感染的胸部影像表现.方法 回顾性分析18例甲型H1N1流感并发肺炎患者的临床及影像资料,将其分为重症组(11例)及危重症组(7例),所有患者均经胸部X线检查,其中2例行CT检查.结果 重症组11例,8例X线表现为双侧肺野中内带分布的、边缘模糊的小斑片和结节状阴影,3例X线表现为局灶性边缘模糊的片状阴影,其中1例胸部CT表现为右下肺大片实变影.危重症组7例,4例X线表现为双肺弥漫分布的磨玻璃密度阴影伴部分实变,其中1例出现胸颈部皮下气肿,1例胸部CT表现为双肺广泛分布的、沿支气管走行的斑片状磨玻璃密度影,双下肺结节状实变病灶和胸腔积液;其他3例表现为双侧肺野内大范围实变影.结论 甲型H1N1流感肺炎的影像表现包括重症患者肺内的结节样和斑片状阴影,危重患者肺内弥漫的支气管周围分布的磨玻璃密度灶和多灶性实变.     

急性混合性气体中毒影像学特征及分析

目的:探讨急性群体混合性气体中毒的影像学特征及远期随访价值.方法:对我院收治的35例急性群体混合性气体中毒患者行常规胸部CT扫描,并选择部分病例行1～4次胸部CT扫描复查病变变化情况;23例行胸部CR检查;28例行头部常规CT扫描.1年后全部病例胸部正侧位CR照片复查远期变化.结果:胸部CT扫描阳性28例(80%),阴性7例(20%),主要表现为支气管炎、支气管周围炎、肺炎、肺水肿及胸腔积液;胸部CR片检查23例,阳性8例(35%),阴性15例(65%),主要表现为两肺纹理增多,双下肺及左下肺小片状模糊影;头部CT 28例均显示正常;1年后胸部正侧位CR片复查,肺部病灶吸收消失,肺纹理恢复到正常人群水平,胸腔积液消失.结论:急性群体混合性气体中毒影像学表现有一定特征性,远期复查意义重大,可为临床诊治提供重要信息.     

农药--百草枯中毒的胸部X线表现(附5例报告)

目的探讨农药一百草枯中毒的胸部x线影像学表现及其临床意义。方法回顾分析5例临床确诊为农药一百草枯中毒的胸部X线影像学特征。结果病变时期的不同，导致了影像学表现的多样化，典型的影像学表现为肺门向肺内散在分布的斑点状或片状阴影3例(60％)，粟粒状阴影2例(40％)．克氏B线1例(20％)，以及磨玻璃样阴影1例(20％)。结论本病的胸部X线影像学表现不具有特异性，但认识其影像学表现结合临床综合分析，对白草枯中毒的诊断与鉴别诊断具有重要意义：     

急性氯气中毒的分期肺部影像表现

目的：探讨急性氯气中毒后各时期的影像学表现及其发展变化的规律.方法：某次氯气泄漏事故中24例中毒患者,男14例,女10例,平均年龄29岁,其中轻度中毒8例,中重度中毒16例.回顾性分析其接受治疗期间（1个月内）的所有肺部影像资料,按急性期、消散期和恢复期分期观察和统计其肺部的各种影像改变.结果：急性期：24例患者接受X线胸片检查,示肺部大片云絮状影13例（13/24）,散在点片状影3例（3/24）,肺部透亮度弥漫性减低18例（18/24）;18例患者行CT检查,CT示肺内出现大片渗出性改变10例（10/18）,散在小片状渗出灶3例（3/18）,肺部磨玻璃密度影17例（17/18）,纵隔气肿3例（3/18）,胸腔积液1例（4/18）.消散期：X线平片显示肺内大片状影部分或绝大部分吸收,肺部透亮度增高;CT示肺部大片影部分或绝大部分吸收,以磨玻璃密度影为主,可见纤维条索影出现,纵隔气肿和胸腔积液减少或消失.恢复期：X线平片示双肺透亮度基本恢复正常,肺内可残留少许条索状或小片状高密度影;CT示肺内弥漫性大片状磨玻璃密度影消失,但可残留散在腺泡结节样磨玻璃密度影或小片状及条索状高密度影.结论：临床上有明确的氯气吸入病史及相应的临床表现,结合影像表现可作出急性氯气中毒的诊断并对肺损害的严重程度作出判断.     

急性胸部闭合性肺挫伤多层螺旋CT检查的临床价值分析

目的 探讨多层螺旋CT检查在急性胸部闭合性肺挫伤诊断中的临床应用价值.方法 回顾性分析了75例急性胸部闭合性肺挫伤患者的螺旋CT表现,并对其CT检查结果和X线检查进行对比分析.结果 本组75例急性胸部闭合性肺挫伤患者中累及双侧肺21例,单侧肺54例.渗出型62例,CT表现为肺纹理不均匀性增粗、边缘模糊,呈网织状改变,其间伴有斑点状、斑片状淡薄影,或表现为肺内单发或多发的斑片状、云雾状稍高密度影,边缘不清.实变型13例,CT表现为肺的一段或一叶实变,呈大片状影,边缘模糊,内可见含气支气管影.本组中合并血气胸27例,肺不张15例,肋骨骨折16例,膈破裂3例.结论 胸部螺旋CT检查对肺挫伤诊断准确率高,,应作为首选的影像检查方法.     

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.     

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.     

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     

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.     

Dynamic contrast-enhanced MR imaging assessment of vascularized free fibular grafts

Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise.     

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.     

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.