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991.
We report a 9-month-old boy who presented with a hard paratesticular mass. Clinical and ultrasound findings were highly suggestive of malignancy and orchidectomy was performed. Histology confirmed the unexpected diagnosis of meconium periorchitis, a rare, benign condition resulting from intrauterine bowel perforation. 相似文献
992.
Ngo AV Sze RW Parisi MT Sidhu M Paladin AM Weinberger E Seidel KD Cunningham ML 《Pediatric radiology》2004,34(7):535-540
Background: In evaluating the effectiveness of ultrasound as a screening tool for craniosynostosis it was discovered that sonologists and sonographers needed more experience scanning and visualizing cranial sutures on ultrasound. Objective: To create an ultrasound simulator to train radiologists and technologists to locate and recognize patent and fused cranial sutures in children. Materials and methods: The hypoechoic appearance of patent sutures was simulated by cutting lines into life-sized plastic doll heads and filling them with a commercial hypoechogenic material. Fused hyperechoic sutures were simulated by not cutting into the hard plastic region of a suture. The simulators teaching value was evaluated on three radiology residents and three fellows. Subjects performed pre-training scans on unknown simulators, received feedback and an opportunity to scan a training simulator, and then performed post-training scans on random unknown simulators. Accuracy was recorded as percentage of correctly demonstrated sutures. Results: The suture simulator reproduces the sonographic appearance of patent and fused cranial sutures. Accuracy of acquisition, interpretation, and overall diagnosis increased from 64 to 91%, 79 to 91%, 61 to 97%, respectively, between pre and post training scans. Conclusion: An ultrasound simulator can reproduce the appearance of patent and fused cranial sutures in children and can be used to train radiologists and technologists in the performance of a screening protocol. 相似文献
993.
We report two children who sustained traumatic parenchymal splenic injury and were monitored with contrast-enhanced ultrasound (CEUS). In both cases, unenhanced US failed to diagnose splenic haematoma, but the injury was well demonstrated after injection of contrast agent. In one case agreement with CT was excellent; in the other, CT was not performed due to the comprehensive information provided by CEUS. 相似文献
994.
Background Ultrasonography is an important tool in the screening and diagnosis of patients with suspected intussusception.Objective To retrospectively evaluate the accuracy and performance of junior residents and compare it to that of senior residents and staff radiologists.Materials and methods Between January 1999 and February 2003, 151 patients with suspected intussusception underwent screening US. The mean age of the patients was 13.8 months. Patients were divided into three groups according to examiner: staff radiologist, senior resident or junior resident.Results Sixty-five patients had both US and air enema. Forty-four patients had a positive US result; 37 (84%) were true positive and 7 (16%) were false positive. Twenty-one patients had a negative US result; 18 (86%) were true negative and 3 (14%) were false negative. Eighty-six patients underwent screening US only and were then kept under observation in the emergency room. They were all diagnosed as having a non-surgical condition. The total accuracy rate was 93%, sensitivity was 84%, specificity was 97%, positive predictive value was 93% and negative predictive value was 94%. Accuracy rate, sensitivity and specificity were 92%, 85% and 98% for staff radiologists, 94%, 75% and 96% for senior residents and 95%, 83% and 97% for junior residents, respectively.Conclusions Junior residents perform as well as staff radiologists in screening US for suspected intussusception and have gained both the respect and confidence of the paediatricians. 相似文献
995.
First trimester ultrasound screening is effective in reducing postterm labor induction rates: a randomized controlled trial 总被引:4,自引:0,他引:4
Bennett KA Crane JM O'shea P Lacelle J Hutchens D Copel JA 《American journal of obstetrics and gynecology》2004,190(4):1077-1081
OBJECTIVE: This study was designed to test the null hypothesis that first trimester ultrasound crown-rump length measurement for gestational age determination will result in no difference in the rate of induction of labor for postterm pregnancy, compared with second trimester biometry alone. STUDY DESIGN: Two hundred eighteen women were randomly assigned to receive either first trimester ultrasound screening or second trimester ultrasound screening to establish the expected date of confinement. Sample size was calculated by using a 2-tailed alpha=.05 and power (1-beta)=80%. Data were analyzed with chi(2) and Fisher exact tests. RESULTS: Of 104 women randomly assigned to the first trimester screening group, 41.3% had their gestational age adjusted on the basis of the crown-rump length measurement. Of 92 women randomly assigned to the second trimester screening group, 10.9% were corrected as a result of biometry (P <.001, relative risk=0.26, 95% CI=0.15-0.46). Five women in the first trimester screening group and 12 women in the second trimester screening group had labor induced for postterm pregnancy (P=0.04, relative risk=0.37, 95% CI=0.14-0.96). CONCLUSION: The application of a program of first trimester ultrasound screening to a low-risk obstetric population results in a significant reduction in the rate of labor induction for postterm pregnancy. 相似文献
996.
Favre R Dreux S Dommergues M Dumez Y Luton D Oury JF Fiblec BL Nisand I Muller F 《American journal of obstetrics and gynecology》2004,190(2):407-412
OBJECTIVE: The purpose of this study was to analyze the precision of ultrasonography in defining the cause and prognosis in fetal ascites. STUDY DESIGN: We conducted a retrospective study of 79 cases of fetal ascites. RESULTS: The mortality rate was 57% overall and ranged from 100% (7/7 cases) for metabolic storage disease to 0% (0/3 cases) in chylous ascites. Ascites before 24 weeks of gestation or combined with fetal hydrops indicates poor prognosis (respectively, 78.6% vs 45% mortality rate after 24 weeks; P<.01; and 77% vs 50.8% without hydrops; P<.02). Ascites was organic in 45 cases, infectious in 13 cases, idiopathic in 12 cases, and genetic in 9 cases. The cause was defined ultrasonographically in 28 of the 45 organic ascites and in 8 of the 25 isolated ascites. Urinary cause was the most frequent and the most successfully specified cause (14/15 cases). CONCLUSION: Routine ultrasonography detects fetal ascites, but the cause is extremely variable and difficult to specify. When associated with fetal hydrops, the prognosis is poor. 相似文献
997.
Seeds JW 《American journal of obstetrics and gynecology》2004,191(2):607-615
OBJECTIVE: Genetic mid-trimester amniocentesis is a common invasive procedure. The origin of the commonly quoted 0.5% rate of procedure-related pregnancy loss after amniocentesis is obscure and is in conflict with the only randomized prospective study that reported a procedure-related rate of loss of 1.0%. This review was performed to establish an estimate of procedure-related pregnancy loss after mid-trimester amniocentesis. The impact of placental puncture on the rate of loss and the risk of direct needle injury to the fetus were also examined. STUDY DESIGN: The National Library of Medicine database was used to identify English language reports of >1000 amniocenteses with sufficient detail and follow up data to allow the calculation of the rate of spontaneous pregnancy loss after amniocentesis but before 28 completed weeks. These reports were divided into 2 groups to assess the impact of the ultrasound technique. Group I described only preamniocentesis ultrasound evaluation; group II described primarily concurrent ultrasound needle guidance. Pregnancy loss between the 2 groups was compared. The impact of placental puncture and reported direct fetal trauma were examined. The significance of differences was tested using chi-square analysis, with significance at a probability value of < or =.05. RESULTS: Twenty-nine reports that totaled 68,119 amniocenteses were examined. In a comparison of all studies in group I with all studies in group II, there was a lower rate of loss after amniocenteses with the use of concurrent guidance (1.4%) compared with the use of preamniocentesis ultrasound evaluation (2.1%) that was significant ( P <.001). Among only the 5 controlled studies that used preamniocentesis ultrasound evaluation, the difference in rate of loss between amniocentesis patients and control subjects was 0.6% ( P =.0042; 95% CI, 0.19, 1.03), which was identical to the difference in the rate of loss of 0.6% between amniocentesis patients and control subjects from the 5 controlled studies that used concurrent ultrasound needle guidance ( P <.0001; 95% CI, 0.31, 0.90). Multiple case reports and small series of presumed fetal needle trauma were reviewed, but most of these attributed causation to the amniocentesis needle based only on circumstantial association. Two cases with direct evidence of fetal needle trauma are discussed. Finally, the rate of loss after placental puncture from among 9 reports that provided this detail was 1.4% and not different from the overall rate of loss that was noted in group II. CONCLUSION: This examination of experience with 68,119 amniocenteses from both controlled and uncontrolled studies provides a substantive basis for several conclusions: (1) Contemporary amniocentesis with concurrent ultrasound guidance in controlled studies appears to be associated with a procedure-related rate of excess pregnancy loss of 0.6% (95% CI, 0.31, 0.90). To determine the total rate of loss, this must be added to the reported natural rate of loss without amniocentesis among control patients of 1.08%. (2) The use of concurrent ultrasound guidance appears to reduce the number of punctures and the incidence of bloody fluid. Concurrent ultrasound guidance was associated with a reduced rate of loss when all studies were compared, but not among controlled studies. (3) Direct fetal needle trauma is rare, and rarely proved, but may occur more frequently than is reported because of a failure to diagnose and a failure of the consistent production of sequelae. (4) This experience does not substantiate an increased rate of pregnancy loss if placental puncture is required. 相似文献
998.
This study was designed to retrospectively determine recent clinical trends of initial radiological evaluation in patients pathologically proven to have acute cholecystitis (AC) and to assess the methodology that led to its diagnosis. Over a 28-month period, the medical records and imaging studies of 117 consecutive patients who had pathologically confirmed AC were retrospectively analyzed. The sensitivities of ultrasound (US) and hepatobiliary 99mTc-iminodiacetic acid (HIDA) were computed. The false-negative scans were retrospectively reviewed by a blinded radiologist to determine the limitations and advantages of each modality. The 117 patients were grouped into six categories based on the type of imaging examination they underwent prior to cholecystectomy: initial US evaluation only (n=80, 68.4%), initial US followed by HIDA (n=17, 14.5%), initial HIDA only (n=2, 1.7%), initial HIDA followed by US (n=3, 2.6%), initial CT (n=5, 4.3%), and no imaging evaluation (n=10, 8.6%). HIDA scan had a calculated sensitivity of 90.9% (20 true-positive, 2 false-negative) while US had a sensitivity of 62% (62 true-positive, 38 false-negative). Current practice in the initial radiological evaluation of acute cholecystitis remains outdated. The vast majority of patients in our study group were initially worked up using US, although HIDA scan has been shown to have greater sensitivity for the diagnosis of acute cholecystitis. 相似文献
999.
1000.
Takase K Kazama T Abe K Chiba Y Saito H Takahashi S 《Cardiovascular and interventional radiology》2004,27(5):520-522
An 82-year-old woman underwent right hemicolectomy by median laparotomy. Two weeks later, a pulsatile mass was found at the left side of the surgical wound, which was diagnosed as pseudoaneurysm of the inferior epigastric artery by color Doppler US and CT. The pseudoaneurysm was successfully treated by US-guided compression of the neck of the aneurysm for 30 minutes. US-guided compression should be considered the treatment of choice for postsurgical pseudoaneurysm of the inferior epigastric artery.
(Present address of author has been changed.) 相似文献