105 research outputs found
Ultrasound Poroelastic Tissue Typing
Employing the poroelastic theory of acoustic waves in gels, the ultrasound (US) propagation in a gel medium filled by poroelastic spherical cells is studied. The equation of fast compressional wave, the phase velocity and the attenuation as a function of the elasticity, porosity and concentration of the cells into the gel matrix are investigated. The outcomes of the theory agree with the preliminary measurements done on PVA gel scaffolds inseminated by porcine liver cells at various concentrations. The feasibility of a non-invasive tech-nique for the health assessment of soft biological tissues steaming by the model is analyzed
Endometriosis: 10 keys points for MRI
Endometriosis is a chronic disease and a clinical problem in women of fertile age, with a high impact on quality of
life, work productivity and health care management.
Two imaging modalities are employed in the diagnosis and evaluation of extent of disease: ultrasound examination
with endovaginal approach and magnetic resonance imaging (MRI). MRI, thanks to its high contrast and
resolution characteristics, offers a high level of accuracy in the study of endometriosis and adenomyosis.
We illustrate here 10 key MRI points for the detection and diagnosis of endometriosis
Dandy-Walker malformation: is the "tail sign" the key sign?
OBJECTIVE.To demonstrate the value of the "tail sign" in the assessment of Dandy-Walker Malformation (DWM).
METHODS:
A total of 31fetal MRI, performed before 24 weeks of gestation after second-line US examination between May 2013 and September 2014, were examined retrospectively. All MRI examinations were performed using a 1.5 Tesla magnet without maternal sedation.
RESULTS:
MRI diagnosed 15/31 cases of Dandy-Walker Malformation, 6/31 cases of vermian partial caudal agenesis, 2/31 of vermian hypoplasia, 4/31 of vermian malrotation, 2/31 of Walker-Warburg Syndrome, 1/31 of Blake pouch cyst, 1/31 of rhombencephalosynapsis. All data were compared with fetopsy results, Fetal MR after the 30th week or postnatal MRI; the follow up depended on the maternal decision to terminate or continue pregnancy. In our review study we found the presence of the "tail sign"; this sign was visible only in Dandy-Walker Malformation and Walker-Warburg Syndrome.
CONCLUSION:
The "tail sign" could be helpful in the difficult differential diagnosis between Dandy Walker, vermian malrotation, vermian hypoplasia and vermian partial agenesis
A prospective study on contrast-enhanced magnetic resonance imaging of testicular lesions: distinctive features of Leydig cell tumours
OBJECTIVES:
Up to 20 % of incidentally found testicular lesions are benign Leydig cell tumours (LCTs). This study evaluates the role of contrast-enhanced magnetic resonance imaging (MRI) in the identification of LCTs in a large prospective cohort study.
MATERIALS AND METHODS:
We enrolled 44 consecutive patients with at least one solid non-palpable testicular lesion who underwent scrotal MRI. Margins of the lesions, signal intensity and pattern of wash-in and wash-out were analysed by two radiologists. The frequency distribution of malignant and benign MRI features in the different groups was compared by using the chi-squared or Fisher's exact test. Sensitivity, specificity, positive and negative predictive value, and diagnostic accuracy were calculated.
RESULTS:
The sensitivity of scrotal MRI to diagnose LCTs was 89.47 % with 95.65 % specificity; sensitivity for malignant lesions was 95.65 % with 80.95 % specificity. A markedly hypointense signal on T2-WI, rapid and marked wash-in followed by a prolonged washout were distinctive features significantly associated with LCTs. Malignant lesions were significantly associated with blurred margins, weak hypointense signal on T2-WI ,and weak and progressive wash-in. The overall diagnostic accuracy was 93 %.
CONCLUSIONS:
LCTs have distinctive contrast-enhanced MRI features that allow the differential diagnosis of incidental testicular lesions.
KEY POINTS:
• MRI is able to characterize testicular lesions suggesting a specific diagnosis. • Rapid and marked wash-in is a common feature of Leydig cell tumours. • Markedly hypointense T2-WI signal is significantly correlated with benign lesions. • Blurred margins and weak hypointense T2-WI signal are correlated with malignant tumours. • Weak and progressive wash-in features are present in 85 % of seminomatous lesions
Role of fetal MRI in the evaluation of isolated and non-isolated corpus callosum dysgenesis: results of a cross-sectional study
PURPOSE:
The aims of this study were to characterize isolated and non-isolated forms of corpus callosum dysgenesis (CCD) at fetal magnetic resonance imaging (MRI) and to identify early predictors of associated anomalies.
METHODS:
We retrospectively analyzed 104 fetuses with CCD undergoing MRI between 2006 and 2016. Corpus callosum, cavum septi pellucidi, biometry, presence of ventriculomegaly, gyration anomalies, cranio-encephalic abnormalities and body malformations were evaluated. Results of genetic tests were also recorded.
RESULTS:
At MRI, isolated CCD was 26.9%, the rest being associated to other abnormalities. In the isolated group, median gestational age at MRI was lower in complete agenesis than in hypoplasia (22 vs 28 weeks). In the group with additional findings, cortical dysplasia was the most frequently associated feature (P = 0.008), with a more frequent occurrence in complete agenesis (70%) versus other forms; mesial frontal lobes were more often involved than other cortical regions (P = 0.006), with polymicrogyria as the most frequent cortical malformation (40%). Multivariate analysis confirmed the association between complete agenesis and cortical dysplasia (odds ratio = 7.29, 95% confidence interval 1.51-35.21).
CONCLUSIONS:
CCD is often complicated by other intra-cranial and extra-cranial findings (cortical dysplasias as the most prevalent) that significantly affect the postnatal prognosis. The present study showed CCD with associated anomalies as more frequent than isolated (73.1%). In isolated forms, severe ventriculomegaly was a reliable herald of future appearance of associated features
Impact of Different e-Cigarette Generation and Models on Cognitive Performances, Craving and Gesture: A Randomized Cross-Over Trial (CogEcig)
Introduction: Most electronic-cigarettes (e-cigarette) are designed to look like traditional cigarettes and simulate the visual, sensory, and behavioral aspects of smoking traditional cigarettes. This research aimed to explore whether different e-cigarette models and smokers' usual classic cigarettes can impact on cognitive performances, craving and gesture. Methods: The study is randomized cross-over trial designed to compare cognitive performances, craving, and gesture in subjects who used first generation electronic cigarettes, second generation electronic cigarettes with their usual cigarettes. (Trial registration: ClinicalTrials.gov number NCT01735487). Results: Cognitive performance was not affected by “group condition.” Within-group repeated measures analyses showed a significant time effect, indicating an increase of participants' current craving measure in group “usual classic cigarettes (group C),” “disposable cigalike electronic cigarette loaded with cartridges with 24 mg nicotine (group H), second generation electronic cigarette, personal vaporizer model Ego C, loaded with liquid nicotine 24 mg (group E). Measures of gesture not differ over the course of the experiment for all the products under investigation Conclusion: All cognitive measures attention, executive function and working memory are not influenced by the different e-cigarette and gender showing that in general electronics cigarettes could become a strong support also from a cognitive point of view for those who decide to quit smoking. It seems that not only craving and other smoke withdrawal symptoms but also cognitive performance is not only linked to the presence of nicotine; this suggests that the reasons behind the dependence and the related difficulty to quit smoking needs to be looked into also other factors like the gesture
Impact of Different e-Cigarette Generation and Models on Cognitive Performances, Craving and Gesture: A Randomized Cross-Over Trial (CogEcig)
Introduction: Most electronic-cigarettes (e-cigarette) are designed to look like traditional cigarettes and simulate the visual, sensory, and behavioral aspects of smoking traditional cigarettes. This research aimed to explore whether different e-cigarette models and smokers' usual classic cigarettes can impact on cognitive performances, craving and gesture.Methods: The study is randomized cross-over trial designed to compare cognitive performances, craving, and gesture in subjects who used first generation electronic cigarettes, second generation electronic cigarettes with their usual cigarettes. (Trial registration: ClinicalTrials.gov number NCT01735487).Results: Cognitive performance was not affected by “group condition.” Within-group repeated measures analyses showed a significant time effect, indicating an increase of participants' current craving measure in group “usual classic cigarettes (group C),” “disposable cigalike electronic cigarette loaded with cartridges with 24 mg nicotine (group H), second generation electronic cigarette, personal vaporizer model Ego C, loaded with liquid nicotine 24 mg (group E). Measures of gesture not differ over the course of the experiment for all the products under investigationConclusion: All cognitive measures attention, executive function and working memory are not influenced by the different e-cigarette and gender showing that in general electronics cigarettes could become a strong support also from a cognitive point of view for those who decide to quit smoking. It seems that not only craving and other smoke withdrawal symptoms but also cognitive performance is not only linked to the presence of nicotine; this suggests that the reasons behind the dependence and the related difficulty to quit smoking needs to be looked into also other factors like the gesture.Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT01735487
Immediate direct-to-implant breast reconstruction: A single center comparison between different procedures
BackgroundThe increased incidence of conservative mastectomy operations (nipple- and skin- sparing) has increased the frequency of immediate breast reconstructions (IBR). In order to guarantee patients the best possible aesthetic outcome, the least chance of complications and moreover, the least postoperative pain, the technique with prepectoral prosthetic pocket was recently reconsidered with the use of ADM. This is the first study using Fortiva® in prepectoral breast reconstruction, and it compares the outcomes of three different patient populations (undergoing retromuscular, prepectoral and prepectoral reconstruction with ADM). The authors suggest that prepectoral breast reconstruction with ADM may bring benefits compared to the current standard technique (retromuscular) as well as compared to the prepectoral reconstruction without ADM.MethodsRetrospective data analysis of patients who underwent mastectomy followed by immediate breast reconstruction with silicone implants (DTI), performed by a team of breast surgeons and plastic surgeons. Logistic factor regressions were performed in order to investigate the effects of the three different intervention techniques on the incidence of complications. Fisher's exact test was used to analyze the differences in the occurrence of each complication. Mann Whitney test was used to compare the averages of referred pain. A p value <0.05 was considered significant.ResultsA total of 67 patients underwent DTI reconstruction, of which 43 with retromuscular prosthesis, 13 prepectoral and 11 prepectoral with ADM. We found a significantly lower incidence of surgical complications with ADM, exclusively in comparison with retromuscular reconstruction (p = 0.028). It emerges prepectoral reconstruction with ADM involves significantly less visibility of the implant than both the prepectoral surgery without ADM (p = 0.013) and the retromuscular technique (p = 0.029). Finally, postoperative pain referred at twelfth month is significantly less relevant in the group with prepectoral prosthesis and ADM, both in the group with retromuscular (p < 0.001) and prepectoral without ADM (p = 0.001).ConclusionsThis study demonstrates that immediate prepectoral breast reconstruction with ADM is a safe and reliable technique, able to exceed some type of limits imposed by prepectoral reconstruction. Moreover, it provides benefits if compared to the current standard technique. In the future, this technique could also be added to it, after a proper selection of patients in pre- and intraoperative time
The evolution of breast prostheses.
Every year approximately 1.5 million prostheses are implanted worldwide for breast augmentation and reconstructive indications. The modern breast implant as we know was released to the open market in 1963. It has gone through intense phases of development which have improved the initially primitive and limited devices to current-day devices, which exhibit a tremendous range of surface textures, sizes, gel consistencies, and anatomical shapes. This article explores the evolution of breast implants providing historical facts and technical details
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