Search results for " Enhancement"
showing 10 items of 521 documents
Acute extrahepatic infectious or inflammatory diseases are a cause of transient mosaic pattern on CT and MR imaging related to sinusoidal dilatation …
2015
To report the association of a mosaic enhancement pattern on contrast-enhanced CT or MR imaging and hepatic sinusoidal dilatation (SD) with acute inflammatory conditions affecting extrahepatic organs. From 2007 to 2012, patients with acute inflammatory diseases who underwent contrast-enhanced CT and/or MRI of the liver with a mosaic enhancement pattern were selected. Clinico-biological and other imaging features were collected at diagnosis and during follow-up. Sixteen patients were included (15 women, median age 27 years; range 18–68). Five women (33 %) were receiving oral contraceptives. Acute inflammatory diseases included pyelonephritis (n = 10), pancreatitis (n = 2), pneumonia (n = 1),…
Characterization of benign hepatic tumors arising in fatty liver with SonoVue and pulse inversion US.
2007
Background: We describe the spectrum of contrast-enhancement patterns of benign hepatic tumors arising in fatty liver on contrast-enhanced ultrasound (US). Methods: Sixteen patients (12 women and four men) with 27 benign hepatic tumors (17 hemangiomas, eight focal nodular hyperplasias, and two hepatocellular adenomas) arising in fatty liver underwent baseline and pulse inversion US after administration of SonoVue. Two experienced radiologists evaluated baseline echogenicity and dynamic enhancement pattern of each lesion in comparison with adjacent liver parenchyma. Results: After administration of SonoVue, in the arterial phase 13 of 17 hemangiomas showed peripheral globular enhancement and…
Heterogeneous delayed enhancement of hepatic parenchyma after intravenous infusion of sonographic contrast agent: a new hypothesis
2007
Purpose. The aim of this paper was to report a heterogeneous latephase hepatic enhancement pattern observed after administration of a sonographic contrast agent and to present an aetiological hypothesis for the phenomenon. Materials and methods. A total of 1,729 (1,012 women and 717 men; age range 28–82; mean age 51) patients underwent contrastenhanced sonography of the liver. The examination was performed with a low mechanical index (MI <0.09) after injection of sulphur-hexafluoride-filled microbubbles, using different fonographic equipment and different contrast-specific algorithms. Results. Heterogeneous delayed liver enhancement was observed in six patients in the late phase (180 s), wi…
Centrifugal (inside-out) enhancement of liver hemangiomas: a possible atypical appearance on contrast-enhanced US.
2007
Abstract Objective To report the prevalence and to describe the atypical centrifugal (inside-out) appearance of contrast-enhancement of liver hemangiomas on contrast-enhanced sonography. Materials and methods Baseline and SonoVue ® -enhanced ultrasonography of 92 patients with 158 liver hemangiomas – considered atypical at grey-scale examination and confirmed by computed tomography, magnetic resonance imaging and ultrasound follow-up – were reviewed in consensus by two experienced radiologists, who evaluated baseline echogenicity and the dynamic enhancement pattern of each lesion looking for the presence of central enhancing foci in the arterial phase followed by a centrifugal (inside-out) …
Fatty replacement of bone marrow after radiation therapy for Hodgkin disease: Quantification with chemical shift imaging
1993
The authors studied the long-term fatty replacement of bone marrow in 23 patients who had received radiation therapy for Hodgkin disease, with T1-weighted magnetic resonance imaging and quantitative chemical shift imaging. T1-weighted images revealed a mostly homogeneous high-signal-intensity pattern, in contrast to the hypointense pattern of nonirradiated marrow. The degree of fatty replacement was objectively assessed with chemical shift imaging, comparing patients to age-matched healthy volunteers. The authors found an increase in relative fat signal of 37% in the thoracic spine and 34% in the lumbar spine. The relative fat signal of nonirradiated pelvic and femoral marrow was decreased …
Standardized T2* map of normal human heart in vivo to correct T2* segmental artefacts.
2007
A segmental, multislice, multi-echo T2* MRI approach could be useful in heart iron-overloaded patients to account for heterogeneous iron distribution, demonstrated by histological studies. However, segmental T2* assessment in heart can be affected by the presence of geometrical and susceptibility artefacts, which can act on different segments in different ways. The aim of this study was to assess T2* value distribution in the left ventricle and to develop a correction procedure to compensate for artefactual variations in segmental analysis. MRI was performed in four groups of 22 subjects each: healthy subjects (I), controls (II) (thalassemia intermedia patients without iron overload), thala…
T2-mapping of the sacroiliac joints at 1.5 Tesla: a feasibility and reproducibility study
2018
Objective: To evaluate the reproducibility of T2 relaxation time measurements of the sacroiliac joints at 1.5 T. Materials and methods: Healthy volunteers underwent an oblique axial multislice multiecho spin-echo sequence of the sacroiliac joints at 1.5 T. Regions of interest were manually drawn using a dedicated software by two musculoskeletal radiologists to include the cartilaginous part of the sacroiliac joints. A senior radiologist performed the measurement twice, while a resident measured once. Intra- and inter-observer reproducibility was tested using the Bland-Altman method. Association between sex and T2 relaxation times was tested using the Mann-Whitney U test. Correlation between…
Lymphoscintigraphy with peritumoral injection versus lymphoscintigraphy with subdermal periareolar injection of technetium-labeled human albumin to i…
2014
Background Preoperative lymphoscintigraphy is without doubt a valid method for the detection of the sentinel lymph node (SLN). There has been considerable debate regarding the optimal site for the introduction of the tracer; various sites include peritumoral (PT), periareolar (PA), subdermal, and intradermal injection. Purpose To evaluate retrospectively the lymphoscintigraphic identification rate of peritumoral (PT) injection versus subdermal periareolar (PA) injection in the detection of SLNs in breast cancer. Material and Methods Between October 2002 and December 2011, a cohort of 906 consecutive patients with biopsy proven breast cancer underwent 914 SLN biopsy procedures. A total of 33…
Statistical methods for the comparison of measurements derived from orthodontic imaging
2000
Biometric comparison procedures for dental imaging methods with continuous outcome were reviewed, mainly concentrating on assessment and comparison of accuracy and precision according to the study design. Univariate graphical and numerical representations of corresponding deviations were summarized to derive a 'check list' of minimum information necessary to compare the measurement methods. The methods reviewed in this investigation are illustrated by the comparison of conventional (radiographic) cephalometry versus assessment using the DigiGraph in 50 female children. A paired t-test and the corresponding confidence interval approach were used to assess deviations in location of two imagin…
Materials and methods of signal enhancement for spectroscopic whole blood analysis: Novel research overview
2017
Abstract The early diagnosis of diseases is crucial for reducing morbidity and mortality and also for improving the quality of treatment process. Among various biological samples used to follow up the concentrations of disease markers, whole blood sensing can efficiently decrease analysis time by means of introducing methods with no pretreatment. In addition, the direct detection of markers in whole blood facilitates testing procedure and minimize the possibility of the loss of analytes in the process. Therefore, the assay of unprocessed whole blood is becoming increasingly important in clinical diagnostics and biomedical research. Incorporation of new advanced materials plays a major role …