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Six normal and 16 neoplastic colorectal specimens were examined with 8.5-MHz ultrasound (US). An articulated system facilitated precise spatial correlation between US and histologic sections. Images were blindly interpreted and then compared with histologic results. All six normal specimen showed five distinct echo layers and were distinguished from neoplastic specimens by all the observers. The central echogenic layer, corresponding to the submucosa, is useful in determining the depth of origin of a neoplasm and the presence of submucosal invasion. US had an accuracy of 92.5% in demonstrating invasion of the submucosa and 77% for invasion of the muscularis externa. For mucosal neoplasms with invasion through the muscularis externa and extension into the subserosal tissues, nearly 90% of US interpretations were correct. High-frequency US may be useful in determining the depth of invasion of mucosal tumors with respect to the submucosa and in differentiating mucosal from extramural masses.  相似文献   
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Tendon echogenicity: ex vivo study   总被引:2,自引:0,他引:2  
Crass  JR; van de Vegte  GL; Harkavy  LA 《Radiology》1988,167(2):499-501
Recent publications discussing the echogenicity of normal tendon have described it variously as hyperechoic or hypoechoic. Since the echogenicity of tendon has been used to define normality and abnormality, certain knowledge of the normal echogenicity of tendon is crucial. Fresh tendon and muscle from beef hock was scanned with sector- and linear-array-transducer imaging at multiple angles and distances. The echogenicity of tendon was found to be very angle-dependent, a characteristic known as anisotropy. Scanned perpendicular to its long axis with a linear-array transducer, tendon was significantly more echogenic than muscle. With a change in angle, echogenicity of tendon decreased relative to that of muscle (the echogenicity of muscle remained the same), becoming isoechoic at angles of 2 degrees -7 degrees and hypoechoic at greater angles. Tendon studied with a sector transducer exhibited varying echogenicity. If echogenicity is used as a diagnostic criterion, the angle of the interrogating ultrasound beam must be very specifically defined.  相似文献   
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Summary. Between 1970 and 1976, 290 patients with endometrial cancer were treated at the 1st Obstetrics and Gynecology Clinic of the University of Milan. The median age was 62 years. Surgery was completed in 262 (90.3%) patients. Abdominal hysterectomy was used in 158 (70.9%) stage I and 40 (71.4%) stage II/III patients; vaginal hysterectomy in 55 (24.7%) stage I and nine (16.1%) stage II/III patients. Resection of the upper vagina was performed in 168 patients. Postoperative external beam radiotherapy was used in stage II/III patients and in 44 (19.7%) stage I high-risk patients. Ten-year survival, determined by the life-table method, was 84.8% in stage I (223 patients), 53.4% in stage II (37 patients), 64.4% in stage III (19 patients), and 9.1% in stage IV (11 patients). Factors associated with poorer prognosis were: late age at diagnosis (P<0.001); deep myometrial invasion (P<0.001); poorly differentiated histological grade ( P =0.11); lack of resection of the upper vagina ( P = 0.13). The role and importance of surgery is discussed, with special emphasis on the selective use of the vaginal route in aged, obese and medically high-risk patients.  相似文献   
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A series of hand and wrist radiographs was assessed manually by two individuals and by a fully automated computer system for determining bone age. Assessments were repeated after 1 month to determine variability between and within the methods of bone age assessment. There was slight intra-observer variation, but complete reproducibility when assessments were made by computer. The variation between the human assessors was less than that between human and computer assessments. The difference between overall maturity scores made by the human observer and the computer system was, however, acceptably small, and the majority of assessments were the same. It is concluded this computer system for assessing bone age in normal children is reliable and accurate, but that it needs to be validated against a much larger set of radiographs.  相似文献   
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