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1.
慢性中耳炎的HRCT诊断   总被引:13,自引:0,他引:13  
探讨慢性中耳炎的HRCT征象,诊断及鉴别诊断。材料与方法;对手术证实的17例慢性中耳炎患者术前进行HRCT扫描并与手术病理结果对照分析。结果;胆脂瘤8例表现为中耳腔内团块状影,周围低密度环包绕,听骨明显破坏及鬓 扩大,骨缘硬化。4例肉芽肿多呈片状,条索状或网状,听骨破坏较轻。  相似文献   
2.
Zusammenfassung Eine neu aufgetretene Dyspnoesymptomatik und eine symmetrische, apikal betonte retikulonodul?re Zeichnungsvermehrung im R?ntgen-Thorax bei jungen rauchenden Erwachsenen müssen an das seltene Krankheitsbild der pulmonalen Histiocytosis X denken lassen. Klinischer Befund, laborchemische- und Lungenfunktionsuntersuchungen zeigen unspezifische Befunde. Neue radiologische Verfahren wie die hochaufl?sende Computertomographie (HRCT) leisten bei gezielter Indikationsstellung eine entscheidende differentialdiagnostische Hilfestellung. Dieser Fall verdeutlicht die M?glichkeit einer Diagnosesicherung durch transbronchiale Biopsien unter Verzicht auf offene Lungenbiopsien. Eine ambulante Diagnostik war m?glich, das h?here Risiko eines operativen Eingriffes konnte vermieden werden. Die Indikation zur Therapie ist nicht gesichert und wird daher durch den Grad der subjektiven bzw. funktionellen Einschr?nkung sowie den Verlauf bestimmt.  相似文献   
3.
A case of pulmonary Langerhans cell histiocytosis, proved by both lung high-resolution computed tomography and lung biopsy, is described. Following smoking cessation, lung nodules and cysts gradually disappeared on serial computed tomography scans, with complete clearance of the lesions after 12 months. The role of tobacco smoking is discussed, in detail, against the background of the literature.  相似文献   
4.
李开信 《实用医技杂志》2004,11(15):1510-1510
胸部疾患影像表现繁多复杂,故选择其检查方法亦需由简入繁,循序渐进.现将我科多年开展的三步法,即X线正位摄片、侧位片、CT扫描,总结如下,供同行参考.  相似文献   
5.
风湿性疾病肺间质变测定方法的评价   总被引:1,自引:0,他引:1  
目的 探讨高分辨率CT(HRCT)、肺功能、胸片等风湿性疾病肺间质病变的诊断价值。方法 对20例不同类型的风湿性疾病患者进行胸片、肺功能、HRCT检测,并将结果进行比较。结果 胸片、肺功能、HRCT对风湿性疾病肺间质病变检出率分别为20%、55%、85%。肺功能和HRCT检出肺间质异常的俩组间比较,差异显著(P〈0.05)。结论 HRCT对风湿性疾病早期,轻度肺间质病变的诊断有高度敏感性,可检出肺功能正常的肺部病变。肺功能尤其弥散功能亦可做为早期肺间质性病变的诊断方法,特别是对那些无明显临床症状、无胸片改变者。当出现弥散功能减低,HRCT出现磨玻璃影、胸膜下线、小叶间隔增厚等异常等,行积极有效治疗,可延缓终末肺发生,改善预后。  相似文献   
6.
Estimations of organ doses DT received during computed tomographic examinations are usually performed by applying conversion factors to basic dose indicators like the computed tomography dose index (CTDI) or the dose-length-product (DLP). In addition to the existing conversion factors for beam apertures of 5 mm or 10 mm, we present new DLP-DT conversion factors adapted to high-resolution CT (HRCT) examinations of infants and young children with beam apertures of the order of 1 mm and under consideration of bow tie filtration. Calculations are performed on mathematical MIRD phantoms for an age range from 0, 1, 5, 10, 15 up to (for comparison) 30 years by adapting PCXMC, a Monte Carlo algorithm originally developed by STUK (Helsinki, Finland) for dose reconstructions in projection radiography. For this purpose, each single slice CT examination is approximated by a series of corresponding virtual planar radiographies comprising all focus positions. The transformation of CT exposure parameters into exposure parameters of the series of corresponding planar radiographies is performed by a specially developed algorithm called XCT. The DLP values are evaluated using the EGSRay code. The new method is verified at a beam aperture of 10 mm by comparison with formerly published conversion factors. We show that the higher spatial resolution leads to an enhanced DLP-DT conversion factor if a small organ (e. g. thyroid gland, mammae, uterus, ovaries, testes) is exactly met by the chosen CT slice, while the conversion factor is drastically reduced if the chosen CT slice is positioned above or below the organ. This effect is utilized for dose-saving examinations with only a few single slices instead a full scan, which technique is applied in about 10% of all paediatric chest CT examinations.  相似文献   
7.
小儿间质性肺炎疾病是儿科少见病。因病因不明、发病机制不清、病程迁延常影响患儿生活质量,甚至影响生长发育,近年报道增多与临床上对该病重视的提高有关。其病理上以肺泡壁损伤、肺间质炎症浸润、纤维细胞增生为主要特征。影像学技术,特别是高分辨力CT在间质性肺病的诊断和预后的判断中具有重要作用。  相似文献   
8.
Hsu HH  Tzao C  Chang WC  Wu CP  Tung HJ  Chen CY  Perng WC 《Chest》2005,127(6):2064-2071
STUDY OBJECTIVES: Zinc chloride smoke inhalation injury (ZCSII) is uncommon and has been rarely described in previous studies. We hypothesized that structural changes of the lung might correlate with pulmonary function. To answer this question, we correlated findings from high-resolution CT (HRCT) scan and the results of pulmonary function tests (PFTs) in patients with ZCSII. DESIGN: Retrospective cohort study. SETTING: University hospital. PATIENTS: Twenty patients who had been hospitalized with ZCSII-related conditions. MEASUREMENTS: The study included HRCT scan scores (0 to 100), static and dynamic lung volumes, and diffusing capacity of the lung for carbon monoxide (D(LCO)). RESULTS: HRCT scans and PFTs were performed initially after injury (range, 3 to 21 days) in all patients and during the follow-up period (range, 27 to 66 days) in 10 patients. The predominant CT scan findings were patchy or diffuse ground-glass opacities with or without consolidation. The majority of patients showed a significant reduction of FVC, FEV1, total lung capacity, and D(LCO), but normal FEV1/FVC ratio values. Changes of functional parameters correlated well with HRCT scan scores. Substantial improvements in CT scan abnormalities and pulmonary function were observed at follow-up. CONCLUSIONS: The majority of our patients with ZCSII presented with a predominant parenchymal injury of the lung that was consistent with a restrictive type of functional impairment and a reduction in Dlco rather than with obstructive disease. Our results suggest that HRCT scanning and pulmonary function testing may reliably predict the severity of ZCSII.  相似文献   
9.
BACKGROUND: Lymphangioleiomyomatosis (LAM), a multisystem disease occurring primarily in women, is characterized by cystic lung destruction, and kidney and lymphatic tumors, caused by the proliferation of abnormal-appearing cells (ie, LAM cells) with a smooth muscle cell phenotype that express melanoma antigens and are capable of metastasizing. Estrogen receptors are present in LAM cells, and this finding, along with reports of disease progression during pregnancy or following exogenous estrogen administration, suggest the involvement of estrogens in the pathogenesis of LAM. Consequently, antiestrogen therapies have been employed in treatment. The goal of this prospective study was to evaluate the efficacy of triptorelin, a gonadotrophin-releasing hormone analogue, in 11 premenopausal women with LAM. METHODS: Patients were evaluated at baseline and every 3 to 6 months thereafter, for a total of 36 months. Hormonal assays, pulmonary function tests, 6-min walk tests, high-resolution CT scans of the chest, and bone mineral density studies were performed. RESULTS: Gonadal suppression was achieved in all patients. Overall, a significant decline in lung function was observed; two patients underwent lung transplantation 1 year after study enrollment, and another patient was lost to follow-up. Treatment with triptorelin was associated with a decline in bone mineral density. CONCLUSIONS: Triptorelin appears not to prevent a decline in lung function in patients with LAM. Its use, however, may be associated with the loss of bone mineral density.  相似文献   
10.
The term ‘emphysema’ is generally used in a morphological sense, and therefore imaging modalities have an important role in diagnosing this disease. In particular, high resolution computed tomography (HRCT) is a reliable tool for demonstrating the pathology of emphysema, even in subtle changes within secondary pulmonary lobules. Generally, pulmonary emphysema is classified into three types related to the lobular anatomy: centrilobular emphysema, panlobular emphysema, and paraseptal emphysema. In this pictorial review, we discuss the radiological – pathological correlation in each type of pulmonary emphysema. HRCT of early centrilobular emphysema shows an evenly distributed centrilobular tiny areas of low attenuation with ill-defined borders. With enlargement of the dilated airspace, the surrounding lung parenchyma is compressed, which enables observation of a clear border between the emphysematous area and the normal lung. Because the disease progresses from the centrilobular portion, normal lung parenchyma in the perilobular portion tends to be preserved, even in a case of far-advanced pulmonary emphysema. In panlobular emphysema, HRCT shows either panlobular low attenuation or ill-defined diffuse low attenuation of the lung. Paraseptal emphysema is characterized by subpleural well-defined cystic spaces. Recent topics related to imaging of pulmonary emphysema will also be discussed, including morphometry of the airway in cases of chronic obstructive pulmonary disease, combined pulmonary fibrosis and pulmonary emphysema, and bronchogenic carcinoma associated with bullous lung disease.  相似文献   
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