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91.
Two cases of rare adrenal cavernous hemangiomas are reported, one imaged with conventional X-ray techniques, US, CT, and MRI, and the other with US and CT. The CT technique clearly demonstrated calcifications and the internal structure of the lesions in both cases and peripheral rim enhancement on the postcontrast scan in one patient. Although MRI demonstrated accurately the complex nature of the lesion, the inability to visualize the calcified areas do not allow to make a specific histologic diagnosis.  相似文献   
92.

Purpose

To describe the computed tomography and ultrasound findings of five cases of small bowel diverticulitis with localized perforation.

Material and methods

Our database, from April 2003 to August 2007, was reviewed and five cases of small bowel diverticulitis were identified.

Results

Jejuno-ileal diverticulitis with covered perforation usually presents as wall thickening of a small bowel loop and an adjacent inflammatory mass containing air bubbles.

Conclusion

Small bowel diverticula are rare and mostly asymptomatic. They become clinically relevant when complications arise, such as diverticulitis. The symptoms of jejuno-ileal diverticulitis are non-specific and the diagnosis is performed mainly by imaging studies.  相似文献   
93.
94.
MRA和彩色双功能多普勒超声诊断颈动脉狭窄的价值   总被引:6,自引:0,他引:6  
目的比较和分析颈动脉狭窄的MRA特征和彩色双功能多普勒超声的表现.材料和方法25例颈动脉狭窄均由彩色多普勒确诊和分级.MRA扫描序列为2维时间飞越技术.结果25例颈动脉狭窄MRA信号缺损大于彩色多普勒超声的斑块长度.9根血流信号中断与脉冲多普勒的舒张期和收缩期血流峰速相关(r=0.685;r=0.828),是血流高速的结果,是中、重度颈动脉狭窄的特征.血管扩张是中度动脉狭窄的重要表现.颈动脉血流消失且无血流重现是血管闭塞的特异征象.结论二维时间飞越MRA在发现和诊断颈动脉狭窄时有一定的临床价值.  相似文献   
95.
The purpose of our study was to compare power Doppler sonography (US) and conventional color Doppler US in the diagnosis of acute appendicitis by revealing local signs of hyperemia. One hundred consecutive patients (46 males and 54 females, ages 7–61 years; mean, 24.7 years) with clinically suspected acute appendicitis were prospectively examined with power Doppler US and conventional color Doppler US. Of 38 patients who subsequently underwent surgery, appendicitis was proven in 34. The remaining 62 patients who were not submitted to surgery had no clinical evidence of appendicitis over a 2- to 6-month follow-up. At gray-scale US, the appendix was visualized in 30 (88.2%) of the 34 cases with pathologically proven acute appendicitis. Power Doppler US depicted a moderate to marked hypervascularity of the appendiceal wall and surrounding mesoappendix in 28 (93.3%) of these 30 patients. At conventional color Doppler US, flow signal within the appendiceal wall and surrounding mesoappendix was shown in only 21 (70%) of 30 cases (P<0.05). No false-positive diagnosis was made at either power or color Doppler US among the 62 patients without appendicitis. Power Doppler US is more sensitive than conventional color Doppler imaging for revealing signs of local hyperemia in acute appendicitis.  相似文献   
96.
A case of hyperreactio luteinalis in an otherwise normal pregnancy is reported. Ascites was present, but no peritoneal implants or adenopathy were seen. Findings that would have suggested the correct diagnosis are the symmetrical and bilateral pattern of the mass, as well as the rather uniform size of the loculi, which were 1 to 3 cm in diameter.  相似文献   
97.

Background and aim

Transabdominal ultrasonography (US) is commonly used for the initial screening of bilio-pancreatic diseases in Asian countries due to its widespread availability, the non-invasiveness and the cost-effectiveness. However, it is considered that US has limits to observe the area, namely the blind area. The observation of the pancreatic tail is particularly difficult. The goal of this study was to examine the pancreatic tail region that cannot be visualized on transverse scanning of the upper abdomen using US with spatial positional information and factors related to visualization, and observation of the tail from the splenic hilum.

Methods

Thirty-nine patients with pancreatic/biliary tract disease underwent CT and US with GPS-like technology and fusion imaging for measurement of the real pancreatic length and the predicted/real unobservable (PU and RU) length of the pancreatic tail. RU from US on transverse scanning and the real pancreatic length were used to determine the unobservable area (UA: RU/the real pancreatic length). Relationships of RU with physical and hematological variables that might influence visualization of the pancreatic tail were investigated.

Results

The real pancreatic length was 160.9 ± 16.4 mm, RU was 41.0 ± 17.8 mm, and UA was 25.3 ± 10.4%. RU was correlated with BMI (R = 0.446, P = 0.004) and waist circumferences (R = 0.354, P = 0.027), and strongly correlated with PU (R = 0.788, P < 0.001). The pancreatic tail was visible from the splenic hilum in 22 (56%) subjects and was completely identified in 13 (33%) subjects.

Conclusions

Combined GPS-like technology with fusion imaging was useful for the objective estimation of the pancreatic blind area.  相似文献   
98.
Purpose: To verify the efficacy of ultrasound (US)-guided injection of large amounts of ethanol into large or multiple liver lesions, in a single session under general anesthesia (one-shot PEI) for percutaneous ablation of hepatic tumors. Methods: Twenty-nine patients (27 with 51 hepatocellular carcinoma (HCC) nodules on cirrhosis, diameter range 1.0<+>–<+>9.0 cm; two patients with a single metastasis from the gastroenteric tract, 5.0 and 9.0 cm, respectively, in diameter) were treated with one-shot PEI. Results: The total volume of alcohol delivered per patient ranged from 16 to 210 ml. Mean ethanol volume in all patients was 49 ml. Dynamic computed tomography (CT) examination showed complete necrosis in 41 of 50 lesions. Two patients died of hypovolemic shock due to massive upper gastrointestinal bleeding, 3 and 7 days, respectively, after the interventional procedure. All the remaining patients are alive (follow-up 5<+>–<+>14 months) except one who died of liver failure 5 months after. New HCC nodules occurred in six patients within 6 months and one intralesional relapse was recorded. Conclusion: In this preliminary experience, one-shot PEI is as effective in inducing liver tumor necrosis as traditional PEI; its advantages are shorter treatment time and the capability of treating larger and multiple liver lesions.  相似文献   
99.
The technique for ethanol injection of liver tumors was modified in order to obtain less reflux with a better intratumoral distribution of ethanol, leading to more extensive necrosis and to a reduction of pain. The needle was stopped just before its entrance into the tumor and ethanol was injected while the needle was advanced a little beyond the distant border of the tumor. Pain and change in echogenicity during and immediately after each injection were evaluated in 11 patients with 38 malignant lesions who received 90 injections with the new or 46 with the conventional technique. Computed tomography and biopsies were used for later follow-up. With the new technique the injected tissue volume converted much more markedly to high echogenicity (p 0.005), the pain was significantly reduced (p 0.001), and posttreatment biopsies significantly less often contained viable cells (p 0.005). These preliminary results suggest that the modified injections were more effective and less painful, and have enabled us to inject a larger volume of ethanol at each session to reduce the number of treatments. Correspondence to: N. M. Elgindy  相似文献   
100.
AIM: To determine if transvaginal ultrasound, including power Doppler examination, can distinguish between women with and without pelvic congestion.MATERIALS AND METHODS: Thirty-six women with pelvic congestion were prospectively examined using transvaginal ultrasonography and standard uterine and ovarian measurements made. Additionally, planimetric measurements of each ovary were taken using an image analysis program to determine the cross-sectional area of ovarian stroma and follicles, if any. Power Doppler images of adnexal vessels were obtained and planimetric estimates of surface area calculated. A congestion score was assigned to each patient, based on vein number, diameter and morphology on grey-scale scanning. Identical measurements were obtained from 19 asymptomatic women and results compared.RESULTS: There was no significant difference between women with pelvic congestion and controls with respect to power Doppler or grey-scale images of adnexal vessels, or congestion score. However, women with pelvic congestion had significantly larger and multicystic ovaries when compared to controls.CONCLUSIONS: Transvaginal ultrasound measurements of adnexal vasculature, including power Doppler measurements, cannot reliably distinguish women with pelvic congestion from controls. However, ultrasound may remain useful for diagnosis of pelvic congestion, predominantly because it is able to visualize multi-cystic ovaries in these patients.  相似文献   
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