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21.
Neuroendocrine tumors of the pancreas: spectrum of appearances on MRI   总被引:5,自引:0,他引:5  
We reviewed our 8.5 year experience with magnetic resonance imaging (MRI) in the demonstration of neuroendocrine tumors of the pancreas using precontrast fat-suppressed T1-weighted, fat-suppressed T2-weighted, and serial post-gadolinium T1-weighted images, to describe the spectrum of appearances of these tumors. All MR examinations of patients with histologically proven neuroendocrine tumors were retrospectively reviewed. Histological type, tumor location, tumor diameter, signal intensity on precontrast images, enhancement patterns, and presence and appearance of metastases were determined. Twenty-two patients had histologically proved neuroendocrine tumors detected by MRI over the 8.5 year period. Histological types were gastrinoma (n = 8), insulinoma (n = 3), glucagonoma (n = 2), somatostatinoma (n = 1), VIPoma (n = 1), ACTHoma (n = 1), carcinoid (n = 1), and five untyped tumors. Primary tumors ranged in diameter from 1 to 6.2 cm. There was one histopathology-proven false-positive neuroendocrine tumor. The positive predictive value for MRI in the detection of these tumors was 96%. The most common appearance on precontrast images was low signal intensity on T1-weighted images and high signal intensity on T2-weighted images, which was observed in tumors in 18 of 22 patients. Moderate or intense early enhancement of all or portions of the primary tumors was observed in tumors in 19 of 22 patients either as uniform homogeneous, ring, or diffuse heterogeneous enhancement. Enhancement was minimal on these images in the other three patients. Gastrinomas enhanced in a ring pattern in 7 of 8 patients whereas the majority (9 of 11 patients) of noninsulinoma-nongastrinoma and untyped tumors enhanced in a diffuse heterogeneous fashion. Liver metastases were present in 13/22 patients including 3/8 with gastrinoma and 9/11 with noninsulinoma-nongastrinoma tumors. Most neuroendocrine tumors of the pancreas are low signal intensity on fat-suppressed T1-weighted images and moderately high in signal intensity on fat-suppressed T2-weighted images, although variations do exist. Tumors most often enhance in an early moderately intense fashion. Gastrinomas are often different in appearance than other neuroendocrine tumors in that they usually enhance in a ring fashion whereas nongastrinoma-noninsulinoma tumors usually enhance in a heterogeneous fashion.  相似文献   
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The technical name for a surgical sponge left in the body of a patient is inadvertent “gossypiboma.” The word is derived from the Latin word Gossypium for cotton and from the Kiswahili word boma for “place of concealment.” These retained sponges were first seen as “textilomas,” but were renamed “gossypiboma” in 1978. The first case was reported by Wilson in 1884. These are rarely are retrieved in the literature, because of legal complications. A higher incidence of retained laparotomy sponges has been reported in association with gynecological procedures. We report a case of gossypiboma in the 38th week of pregnancy that imitated an ovary neoplasm.  相似文献   
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Patients with solitary kidneys (SKs) are at risk of hypertension (HT) and associated end‐organ damage. The authors aimed to evaluate whether children with congenital SKs (CSKs) have higher office, ambulatory, or central blood pressure (BP), increased arterial stiffness or left ventricular mass index, or any risk for arrhythmia. With this purpose, patients with CSK and healthy controls being followed up between January 2018 and June 2019 were enrolled in the study. Demographic, biochemical, and office blood pressure (BP) data were recorded. Then, ambulatory blood pressure monitoring (ABPM) and measurements of central BP (cBP), pulse wave velocity (PWV), and augmentation index (AIx@75) were obtained. Ventricular repolarization parameters were acquired by 12‐lead electrocardiography. Left ventricular mass index (LVMI) and abdominal aortic stiffness parameters including strain, pressure strain elastic modulus (Ep), and normalized Ep (Ep*) were calculated with echocardiographic measurements. Finally, 36 children with CSK and 36 healthy controls were included. Serum creatinine, uric acid, total cholesterol levels, ABPM parameters, cBP levels, and PWV values were significantly higher, and eGFR levels were significantly lower in the CSK group. VR parameters, abdominal aortic stiffness indices, and LVMI were similar between the groups. CSK increased the risk of HT in ABPM (HTABPM) by 6 times. PWV was significantly correlated with Ep and Ep* in cases with CSK. Determination of cBP and PWV along with 24‐hour ABPM would be a useful tool in children with CSK.  相似文献   
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Patients with asthma develop pulmonary hypertension due to recurrent hypoxia and chronic inflammation, leading to right heart enlargement with ventricular hypertrophy. Patients with severe asthma can experience cor pulmonale later in life, but little is known about ventricular function during the early stages of the disease. This study aimed to investigate ventricular functions in asymptomatic children with asthma as detected by conventional echocardiography and tissue Doppler echocardiography (TDE). Fifty-one pediatric patients (mean age 10.4 ± 2.2 years) with asthma and 46 age- and sex-matched healthy children (mean age 10.9 ± 2.4 years) were studied. All subjects were examined by conventional echocardiography and TDE, and they had pulmonary function tests on spirometry. The right-ventricular (RV) wall was statistically (p = 0.01) thicker among asthmatic patients (4.7 ± 1.5 mm) compared with healthy children (3.6 ± 0.4 mm). However, conventional pulsed-Doppler indices of both ventricles did not differ significantly between asthmatic patients and healthy children (p > 0.05). The results of TDE examining RV diastolic function showed that annular peak velocity during early diastole (E′), annular peak velocity during late diastole (A′) (16.4 ± 1.8 and 5.1 ± 1.4 cm/s, respectively), E′/A′ ratio (3.2 ± 0.7), isovolumetric relaxation time (67.7 ± 10.2 ms) and myocardial performance index (48.1 % ± 7.0 %) of the lateral tricuspid annulus among asthmatic patients differed significantly (p = 0.01) from those of healthy children (13.2 ± 2.3, 8.2 ± 2.0 cm/s, 1.6 ± 0.5, 46.2 ± 8.7 ms, and 42.0 % ± 5.7 %, respectively). Only peak expiratory flow (PEF) rate from the pulmonary function tests was negatively correlated with the E′/A′ ratio of the tricuspid annulus (r = ?0.38, p = 0.01). This study showed that although the findings of clinical and conventional echocardiography were apparently normal in children with asthma, TDE showed subclinical dysfunction of the right ventricle, which is negatively correlated with PEF. These findings signify the diagnostic value of TDE in the early detection and monitoring of such deleterious effects among asthmatic patients.  相似文献   
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