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911.
PURPOSE: Because sonography identifies abnormalities of the gastroesophageal junction, it is essential to understand the normal sonographic anatomy. The aim of this study was to determine the normal sonographic appearance of the gastroesophageal junction and its variations and to provide measurements of the abdominal esophagus in asymptomatic, healthy children. METHODS: In this prospective study, 124 healthy children (75 boys and 49 girls), aged 2 days-12 years, underwent abdominal sonography. With the patient in a supine position, the transducer was placed under the xiphoid and the ultrasound beam was directed cephalad through the window of the left lobe of the liver. The length of the abdominal esophagus was measured from the point at which it penetrated the diaphragm to the gastroesophageal junction. The thickness was measured on the anterior wall at the midpoint of the abdominal esophagus. RESULTS: The gastroesophageal junction was identified by sonography in all of the children. The mean length of the abdominal portion of the esophagus ranged from 18 mm in the newborns to 34 mm in children older than 6 years. The wall thickness ranged from 2.4 mm to 5.7 mm. CONCLUSIONS: Our results indicate that visualization of the gastroesophageal junction and measurement of the abdominal esophagus are readily achievable with real-time sonography in healthy children.  相似文献   
912.
Abstract

Objective: Nuchal translucency (NT) thickness is one of the major screening markers during the first trimester that could be influenced by several factors. Here, we investigated the association between NT thickness and thyroid related hormones.

Methods: NT thickness was measured with transabdominal ultrasound in 643 pregnant women between 11 and 13 weeks of gestation. Maternal thyroxine (T4), free thyroxine (fT4) and thyroid-stimulating hormone (TSH) were evaluated. Bivariate correlations were assessed and thyroid profile was subcategorized with regard to the calculated reference ranges.

Results: An inverse relation was found between serum levels of maternal T4 with NT thickness (r?=??0.128, p?=?0.001) and CRL (r?=??0.168, p?<?0.001). TSH and hCG were also found to be correlated (Spearman’s correlation coefficient?=??0.092, p?=?0.019). Prevalence of maternal hypothyroidism and subclinical hypothyroidism were 1.1% and 3.7%, respectively.

Conclusion: Thyroid function tests are found to independently influence NT measurements in the first trimester. Assessment of hormones such as thyroxine could optimize the interpretation of screening tests for pathological conditions during pregnancy.  相似文献   
913.
Intestinal ultrasonography has emerged as a cheap, non-invasive and readily accessible modality for the assessment of a number of gastroenterological diseases. Over the last decade, particularly due to the widespread use of biological agents in Inflammatory Bowel Disease (IBD), guidelines regarding management and follow-up advise more regular disease assessment and surveillance in order to guide treatment adjustments, and provide more personalised care. Given the young age of the majority of patients with IBD the availability of an alternative modality to harmful radiation or the risks of endoscopy for this indication offers an appealing advantage. Intestinal ultrasonography has been shown to be as sensitive and specific for detecting IBD as both computed tomography and magnetic resonance enterography, and endoscopic evaluation. More recent developments in the technology of ultrasonography equipment and the use of intravenous contrast agents (contrast enhanced ultrasonography, known as CEUS), have significantly increased the ability to both detect disease location, determine the disease activity and also potentially the difference between fibrotic and inflammatory segments. This review focusses specifically on the value of CEUS for the diagnosis of both Crohn’s disease and Ulcerative Colitis, in determining disease activity, extraintestinal complications, determination of fibrosis as well as its more recent use in assessing and predicting response to biological and immunosuppressive therapies.  相似文献   
914.
The authors emphasize the importance of performing an intrapartum ultrasonography in order to prevent maternal and neonatal complications but also physician legal liability. The main advantages of using this technique are: improvement of fetal head’s malposition diagnosis; prevention of maternal and fetal complications of childbirth due to the use of forceps or vacuum extractor (VE); a more accurate planning of cesarean section; a proof of professional correctness.  相似文献   
915.
A 60‐year‐old man had a positive fecal occult‐blood test on a medical check‐up. Colonoscopy revealed a yellowish‐white submucosal tumor 8 mm in diameter in the rectum. Endoscopic ultrasonography showed a well‐demarcated mass with a homogeneous, low‐level, internal echo in the second to third layers of the rectal wall. A carcinoid tumor was suspected, and the mass was resected endoscopically. Histopathological examination revealed a granular‐cell tumor. Gastrointestinal granular‐cell tumors rarely arise in the rectum, and the preoperative diagnosis of small lesions is often difficult. In our patient, granular‐cell tumor was difficult to differentially diagnose because the endoscopic and endoscopic ultrasonographic findings closely resembled those of carcinoid tumor. Interestingly, the endoscopic characteristics of the rectal granular‐cell tumor in our patient resembled those of a carcinoid tumor.  相似文献   
916.
917.
Background: Intraductal ultrasonography of the bile/pancreatic duct using a thin‐caliber ultrasonic probe (IDUS) provides excellent images of these ducts and the surrounding structures. Insertion of the device through the papilla of Vater is essential to carry out this examination. We developed a new probe with a ropeway system (XUM5RG‐29R; Olympus, Tokyo) for transpapillary IDUS. Its usefulness such as ease of application and safety were prospectively evaluated. Patients and methods: During the period of October 1997 to April 1998, transpapillary IDUS using the probe was performed in 194 patients at seven medical institutions. The success rates of insertion of the probe into the bile/pancreatic duct, observation of the area of interest, and the incidence of complications were evaluated. Results: Passage of the probe through the papilla was successful without difficulty in all the patients. Successful introduction of the probe into the pancreatic duct, bile duct and both of the ducts was achieved in 98.4, 100 and 85% of the patients, respectively. Once the probe was introduced into the aimed duct, it was possible to obtain IDUS images of the area of interest in all but five patients. Mild acute pancreatitis developed in eight patients (4.1%), all of whom recovered with conservative therapy only. Conclusions: It is possible to introduce the new ultrasonic probe into the desired duct once a guide wire has been inserted. This type of ultrasonic probe is quite useful when performing transpapillary IDUS of the bile and/or pancreatic duct.  相似文献   
918.
Purpose  This article describes an investigation of the detectability of breast microcalcifications by ultrasound imaging. Methods  Two kinds of experiments were performed to evaluate the spatial and contrast resolution of microstructures in an agar graphite phantom and to analyze human perception of tiny spots. Results  The results showed that most of the difficulties in finding microstructures were not only due to lower echo levels but also to obstructions in the surrounding texture of the image. Based on these results, a new image processing method was proposed to emphasize microcalcifications in mammary glands. This method utilized statistical analysis of the echo signals and also considered the structural pattern of the mammary gland. Processed images from some clinical cases showed adequate extraction of the microcalcifications with efficient cancellation of the mammary gland structure. Conclusion  The results suggested that the perception of microcalcifications could be improved by the proposed method.  相似文献   
919.
BACKGROUND: Tuberculous peritonitis (TBP) is a rare manifestation of childhood tuberculosis characterized by long-lasting abdominal symptoms and exudate and lymphocytes in the ascitic fluid. The diagnosis of TBP is rarely established unless a high index of suspicion is maintained. METHODS: The diagnostic features of 11 cases who were hospitalized with TBP in the Pediatric Infectious Diseases Ward of Dicle University Hospital, Turkey, were evaluated retrospectively. RESULTS: Seven cases were male and the ages of all cases ranged between 1 and 11 years. The onset of symptoms was 1-12 months (mean +/- SD 3.1 +/- 2.7 months) prior to the admission time. Nine patients gave a history of familial tuberculosis. Three cases had Bacillus Calmette-Guérin (BCG) scars and the results of five tuberculin unit (TU) tests in cases without and with BCG were over 10 and 15 mm, respectively. The most common presenting clinical symptoms and signs at admission were abdominal distention and ascites (100%), fever (27%) and loss of weight (18%). One case had accompanying tuberculous meningitis and two cases had concomitant pulmonary tuberculosis. Only one of 11 samples of ascitic fluid yielded Mycobacterium tuberculosis by the polymerase chain reaction method and no other microbiologic evidence was obtained in culture specimens. Ultrasonographic and computed tomographic imagings revealed high-density ascites that contributed well to the diagnosis. The diagnosis in two patients was proven histopathologically via peritoneoscopy and laparoscopy. All cases were treated with isoniazide, rifampisin for 9 months and pyrazinamide for the first 2 months. CONCLUSIONS: Radiologic diagnostic techniques, positive skin tests and a history of exposure to tuberculosis may contribute to the diagnosis of TBP, helped by clinical symptoms and findings, particularly when invasive diagnostic methods via peritoneoscopy and laparoscopy are not available in developing countries.  相似文献   
920.
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