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1.
The adrenal glands are affected by complex physiologic and neoplastic processes. Recently described computed tomography densitometry and chemical shift MR imaging techniques are useful to distinguish between benign and malignant masses. Knowledge of the basic gross pathologic and histologic correlates of adrenal disease helps in applying these new imaging methods and in understanding established cross-sectional studies.  相似文献   

2.
The advent of newer imaging techniques, such as high resolution MR imaging and surface reconstructions of 3-dimensional data sets, has led to a greater in-vivo understanding of cortical malformations of the brain. The disorders of cortical formation are illustrated with routine imaging, surface reconstruction, and pathologic specimens.  相似文献   

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A variety of benign and malignant non-squamous cell neoplasms may affect the larynx. Most of these uncommon laryngeal neoplasms are located beneath an intact mucosa, making diagnosis difficult with endoscopy alone, and sampling errors may occur if only traditional superficial biopsies are performed. In some laryngeal neoplasms, radiologic evaluation allows the correct diagnosis. Hemangiomas have very high signal intensity at T2-weighted magnetic resonance (MR) imaging and strong enhancement at both computed tomography (CT) and MR imaging after administration of contrast material. Phleboliths, which are pathognomonic for hemangiomas, are easily identified at CT. Chondrogenic tumors typically manifest with coarse or stippled calcifications at CT. Because of their high water content, chondrogenic tumors have very high signal intensity on T2-weighted MR images, whereas only moderate enhancement is observed after administration of contrast material. Lipomas typically manifest at both CT and MR imaging as homogeneous nonenhancing lesions. They are isoattenuating to subcutaneous fat at CT and isointense relative to subcutaneous fat with all MR pulse sequences. Metastases from renal adenocarcinoma typically demonstrate strong contrast enhancement and flow voids at MR imaging, and metastases from melanotic melanoma usually have high signal intensity on T1-weighted MR images and low signal intensity on T2-weighted images owing to the paramagnetic properties of melanin. Although radiologic findings are nonspecific in most other non-squamous cell neoplasms of the larynx (eg, Kaposi sarcoma, hematopoietic tumors, tumors of the minor salivary glands, metastases from amelanotic melanoma), cross-sectional imaging can play an important role in the diagnostic work-up of these unusual tumors by delineating the extent of submucosal tumor spread and directing the endoscopist to the appropriate site for the deep, transmucosal biopsies needed to establish the diagnosis. In addition, CT and MR imaging are crucial for posttherapeutic monitoring and early detection of local recurrence.  相似文献   

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Complex physiologic and neoplastic processes affect the adrenal glands. An appreciation of the gross pathologic and histologic correlates of disease aids in understanding the mechanisms by which diagnostic imaging helps characterize adrenal masses. Computed tomographic (CT) densitometry and chemical shift magnetic resonance (MR) imaging would seem to be the most reliable tools in determining whether a given adrenal mass is specifically an adenoma. Such a determination is made on the basis of the presence of substantial amounts of intracytoplasmic lipid. Thus, although a homogeneous mass with a CT attenuation of less than 10 HU or a decrease in signal intensity at opposed-phase MR imaging is diagnostic for adenoma, lesions that do not have these features are indeterminate and may necessitate biopsy. Adrenal myelolipoma also has a distinctive imaging appearance that reflects the presence of macroscopic fat deposits. Diagnosis of adenoma or adrenal myelolipoma is very helpful in the assessment and treatment of asymptomatic patients with adrenal masses and may make biopsy unnecessary. In patients with clinical or biochemical evidence of adrenal disease, MR imaging helps confirm the presence of a mass and allows localization and further characterization of the lesion.  相似文献   

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Technical advances in magnetic resonance imaging (MRI), notably in high-resolution MRI, have opened up new diagnostic applications in male pelvic pathology. A major indication is the preoperative staging of prostate cancer, where MRI is more reliable than other imaging modalities in differentiating between localized and advanced disease. In monitoring local recurrence after radical prostatectomy MRI is also valuable in differentiating scar tissue from new growth. In benign prostate disease, MRI effectively displays the congenital cysts that may be associated with infertility. Other disease, however - notably benign prostatic hyperplasia - is generally an incidental finding. Ultrasound remains the imaging modality of choice for evaluation of pathologies of the penis, testis and scrotum, e. g. in differentiating malignant from benign scrotal masses or in diagnosing acute scrotum due to testicular torsion or rupture. In isolated cases, MRI is also a valuable diagnostic aid in conditions of these organs, e. g. in the preoperative localization of ectopic testes in cryptorchidism or if US findings are equivocal.  相似文献   

7.
Gastrointestinal involvement is commonly found in scleroderma. Gastrointestinal symptoms may be the presenting symptoms for the diagnosis and may precede the actual diagnosis by months to years. The esophagus is the most frequently affected, but functional problems of the anorectum, small bowel, colon, and stomach may occur. The pathophysiologic mechanism appears to be one of smooth muscle atrophy and, to a lesser degree, fibrosis. These changes result in gastrointestinal motility disturbances and may cause GERD, pseudo-obstruction, bacterial overgrowth, and defecatory disorders. Malnutrition may be a serious consequence. The evaluation of a particular symptom in a patient with scleroderma may lead to treatment strategies that improve the patient's sense of well-being and quality of life.  相似文献   

8.
We correlated high-resolution CT (HR-CT) images of 30 surgically resected epidermoid carcinomas in peripheral lung fields with pathologic findings. We classified peripheral epidermoid carcinomas into three types based on HR-CT findings. All tumors showed a notch along their margin. Type 1 shows scanty speculations without the convergence of surrounding lung structures. Type 2, which has two subtypes, shows a spiculated border with the convergence of peripheral lung structures. Type 2a has fine irregularities in its border, while type 2b has few fine irregularities. The convergence of peripheral lung structures seen in type 2 carcinoma is caused by the presence of scar tissue within tumors. Speculations corresponded to tumor extension or lymphocytic infiltration, sometimes along pulmonary vessels or interlobular septa, and fine irregularities seen in type 2a corresponded to summation of fibrous thickening of alveolar septa. Nine tumors showed varying-sized cavities, which were caused by the circulatory disturbance and/or central necrosis seen in tumor nests. In conclusion, HR-CT images were well correlated with pathologic findings of the resected specimens; however, some type 2a tumors may mimic adenocarcinoma on HR-CT findings.  相似文献   

9.
Current debate over the influence of phonological awareness on early reading development is polarised around small-unit (phoneme) processing and large-unit (onset-rime) processing. These opposing theories were contrasted by assessing the impact of pre-school phonological skills on reading amongst children experiencing their first year of formal instruction by a mixed method. Those beginning readers who could decode nonwords were found to have accomplished this by employing their letter-sound knowledge rather than by making analogies based on familiar rime units. Children displayed this pattern of performance regardless of their pre-school rhyming skills. Further investigations revealed that explicit awareness of onset and rime units was poor, even amongst children whose implicit rhyming skills were excellent. This evidence, together with the children's knowledge of orthographic units, was consistent with the view that letter-sound correspondences rather than onset or rime units formed the basis of their first attempts to utilise phonology in reading. The findings are discussed with reference to instructional influences on early reading and phonological awareness.  相似文献   

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Prognosis for patients with cystic fibrosis has improved dramatically over the past three decades. In the United States, median survival age is now 28.9 years. Although genotype predicts exocrine pancreatic function, it does not correlate with pulmonary status or overall clinical outcome. However, there are a number of parameters, such as exocrine pancreatic sufficiency, male gender, absence of colonization with mucoid Pseudomonas aeruginosa, presentation with predominantly gastrointestinal symptoms, balanced family functioning and coping, and compliance with treatment regimens, that predict a more favorable outcome. The impact of early diagnosis and treatment is still controversial. Although nonblinded studies indicate decreased morbidity in the first 2 to 4 years of life among patients diagnosed by newborn screening, no data support long-term benefit in terms of pulmonary function or survival. With increased longevity, there is now evidence of a small but significantly increased risk of gastrointestinal tract cancer among patients with cystic fibrosis.  相似文献   

13.
Cystic fibrosis is the most common life-threatening autosomal recessive genetic disorder in Caucasian populations. It is a disease primarily of epithelial tissues, including the airway, pancreatic duct, intestine, genital tract and sweat glands. The affected gene was cloned and characterized in 1989. In the absence of an identified natural animal model of the disease, a major effort has been made to develop transgenic cystic fibrosis mice, by disrupting the gene in these laboratory animals. Such mice show many, but not all, of the symptoms of cystic fibrosis. In this article, the major past and present contributions of other animal systems to our understanding of cystic fibrosis are examined and their potential for future studies of this disease are discussed. It is intended to give the reader a broad overview of the field, exploring the usefulness of animal studies, rather than dealing more fully with specific aspects of cystic fibrosis.  相似文献   

14.
A patient of cystic fibrosis is hereby reported. He had no family history and presented with chest symptoms, only. There was no evidence of hepatic or pancreatic involvement. To our knowledge this represents the first case of its kind from this part of country.  相似文献   

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Improved survival for cystic fibrosis has rapidly increased over the past four decades, with patients now living well into adult life. With changes in the structure of the National Health Service and the formation of provider units and general practitioner (GP) fund-holding practices, it is important to strengthen links between the hospital and community teams to ensure that the CF patient receives adequate care. Increasingly, treatment is being carried out at home, and this emphasis on home-based therapy demands that parents/carers and patients must acquire the skills and knowledge of complex therapies in order to optimize health. It is the role of the CF nurse specialist (NS) to educate those who will deliver the care, co-ordinate the provision of services at home, liaise with the CF team and community health-care professionals and to support the patient and their carers.  相似文献   

16.
In this article the author explains nasal intermittent positive pressure ventilation (NIPPV) for patients with cystic fibrosis (CF). Indications for use are noted before nursing care of the patient is described in detail.  相似文献   

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Retrospectively the ultrasonographic findings of 153 surgically resected cystic thyroid nodules were reviewed. The pathologic findings in this series revealed that 86% were degenerating benign adenomas or adenomatous goiters, and 14% were malignant tumors. The sonographic appearance of these lesions was classified into 7 groups as follows: type I: entirely cystic (less than 1cm), type II: cystic(more than 1cm) [II(a)], and with small polyp or dome-like elevation on the cyst wall [II(b)], type III: larger cyst with projection (more than 1cm) into the lumen, type IV: cyst with a peripherally localized solid component, type V: irregularly mixed cystic and solid components, type VI: a solid mass with multiple crescentic cysts [VI(a)], or round cysts [VI(b)], type VII: a solid mass with only one or two cysts. Pathologic correlation revealed that malignancy in this series ranged from 80% in type III and V to only 4% in type II, where most of the lesions in this group were composed of granulation tissue in degenerating adenomatous polyps and cyst walls. Lesions in type IV showed malignancy rate of 40%. Type III showed characteristic sonographic findings seen in cystic papillary carcinomas (CPCs), with multiple punctate echogenic foci in large pedunculated projections. The typical psammomatous calcifications specific in this group were confirmed in 6 of the 8 type III CPCs. The multiple crescentic cysts in type VI(a) lesions were characteristic sonographic signs seen in adenomatous goiters, representing the pathologic finding of cysts forming around each of multiple adenomatous nodules in this group. Type VII represented non specific appearing lesions, included adenomas, adenomatous goiters, CPCs and follicular carcinomas.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
This reprint of an article that first appeared in Nucleonics in 1966 provides a unique perspective of the introduction of the cyclotron into clinical medicine and medical research. The cyclotron offers a potentially powerful tool to biomedical centers. With this accelerator one can produce a variety of short-lived nuclides that are unavailable from other sources.  相似文献   

20.
PURPOSE: To assess the non-cutaneous involvement in primary B-cell non-Hodgkin's lymphoma (NHL) of the skin. PATIENTS AND METHODS: Data from 45 patients with B-cell NHL of the skin were retrospectively analysed. The patients were diagnosed on histologic and immunocytochemical grounds between June 1977 and July 1993, and 14 cases were selected for their exclusively cutaneous initial involvement. Initial treatment, response to therapy, disease-free survival characteristics of relapse and therapeutic sequence were evaluated in every case. RESULTS: Cutaneous involvement presented as nodules or patches, on a single location, in 12 cases, or disseminated, in 2 others. No prognostic factor could be identified, and complete remission was attained in all cases. Cutaneous relapse was seen in 7 patients after 4 to 108 months since diagnosis. Extracutaneous dissemination was not seen in any case, and 13 patients are alive and disease-free. A 90 year-old woman died of toxic complications. CONCLUSIONS: The clinical facts reported here confirm the not too aggressive behaviour of certain B-cell cutaneous NHL, probably related with their origin on the skin itself.  相似文献   

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