246 research outputs found
Three-dimensional volumetric analysis of the maxillary sinus: a cone-beam computed tomography study
Background: This study aimed to determine the volumetric size of the maxillary sinus and investigate the effect of gender and age on maxillary sinus volume (MSV) using cone-beam computed tomography (CBCT) images in a Turkish subpopulation.
Materials and methods: This retrospective volumetric CBCT study was carried out on 133 individuals (84 females, 49 males) between 8 and 51 years old. MSV was measured using the MIMICS 21.0 software (Materialise HQ Technologielaan, Leuven, Belgium). All statistical analyses were performed using the SPSS 21.0 (SPSS, Chicago, IL, USA) software. Mean and standard deviation of both maxillary sinuses measurements were calculated and compared to gender and age. P values < 0.05 were considered to indicate statistical significance.
Results: Mean volume of the right maxillary sinus was 13.173 cm3, while for the left was 13.194 cm3. There was no significant difference between right and left maxillary sinus volumes (p > 0.05). There was no significant correlation between MSV and age (p > 0.05). It was found that MSV did not change according to gender (p > 0.05).
Conclusions: Right and left maxillary sinus volumes were not different from each other. Gender and age were not found to be related to maxillary sinus volume
Comparison of posterior cranial fossa morphometric measurements in Chiari type I patients with and without syrinx cavity on magnetic resonance imaging
Purpose: To compare the posterior fossa measurements of Chiari type I malformation (CHM1) patients with and without syrinx and with a control group. Material and methods: The patients with syrinx were divided into 2 groupd according to syrinx width/cord width (S/C) ratios: group 1 – S/C ratio 50%. The length of the clivus, the AP length of the foramen magnum, the AP length of the posterior fossa, the perpendicular distance between the McRae line and (a) the splenium of corpus callosum, (b) the pons, and (c) the fastigium of the 160 patients and of the 160 control patients were statistically compared. In addition, the measurements of the patients with and without syrinx, according to the S/C ratio, were statistically compared. Results: Syrinx was present in 59 (36.8 %) of the 160 patients. The S/C ratio was 50% in 29 (49.1%) of them. All the measurements in the patient group, except of the AP length of the foramen magnum, were statistically significantly lower than in the control group (p = 0.001). There was no signif icant difference in the measurements of the patients with syrinx group 1 and the patients without syrinx, but the AP length of posterior fossa was statistically significantly lower in the patients with syrinx group 2 than the patients without syrinx (p = 0.03). Conclusion: The S/C ratio can be a guide to the underlying aetiology
The relation between endothelial dependent flow mediated dilation of the brachial artery and coronary collateral development – a cross sectional study
<p>Abstract</p> <p>Background</p> <p>Endothelial dysfunction is thought to be a potential mechanism for the decreased presence of coronary collaterals. The aim of the study was to investigate the association between systemic endothelial function and the extent of coronary collaterals.</p> <p>Methods</p> <p>We investigated the association between endothelial function assessed via flow mediated dilation (FMD) of the brachial artery following reactive hyperemia and the extent of coronary collaterals graded from 0 to 3 according to Rentrop classification in a cohort of 171 consecutive patients who had high grade coronary stenosis or occlusion on their angiograms.</p> <p>Results</p> <p>Mean age was 61 years and 75% were males. Of the 171 patients 88 (51%) had well developed collaterals (grades of 2 or 3) whereas 83 (49%) had impaired collateral development (grades of 0 or 1). Patients with poor collaterals were significantly more likely to have diabetes (<it>p </it>= 0.001), but less likely to have used statins (<it>p </it>= 0.083). FMD measurements were not significantly different among good and poor collateral groups (11.5 ± 5.6 vs. 10.4 ± 6.2% respectively, <it>p </it>= 0.214). Nitroglycerin mediated dilation was also similar (13.4 ± 5.9 vs. 12.8 ± 6.5%, <it>p </it>= 0.521).</p> <p>Conclusion</p> <p>No significant association was found between the extent of angiographically visible coronary collaterals and systemic endothelial function assessed by FMD of the brachial artery.</p
CENGO: a web-based serious game to increase the programming knowledge levels of computer engineering students
In recent years, games are used to increase the level of knowledge and experience of individuals working in different domains. Especially in the education field, there are several different serious games
to teach the subjects of the lectures or other educational materials to
students in an enjoyable way. Hence, this study proposes a quantitative
research approach to increase the programming knowledge levels of the
first-year undergraduate students at computer engineering departments.
For this aim, a responsive web platform was developed to teach the syntax and logic of C programming language by using some game elements.
Therefore, the students have a chance to repeat the topics related to C
programming language continuously since the platform is always accessible. To figure out the efficiency of the designed environment, 10 first-year
computer engineering students were selected. According to the results obtained from the user tests, this game can be used as an educational tool,
which supports the traditional training methods, to increase the knowledge levels of students about the syntax and logic of C programming
language
Heterogeneity of microsphere distribution in resected liver and tumour tissue following selective intrahepatic radiotherapy
Split-screen single-camera stereoscopic PIV application to a turbulent confined swirling layer with free surface
Quantitative Evaluation of Scintillation Camera Imaging Characteristics of Isotopes Used in Liver Radioembolization
Scintillation camera imaging is used for treatment planning and post-treatment dosimetry in liver radioembolization (RE). In yttrium-90 (90Y) RE, scintigraphic images of technetium-99m (99mTc) are used for treatment planning, while 90Y Bremsstrahlung images are used for post-treatment dosimetry. In holmium-166 (166Ho) RE, scintigraphic images of 166Ho can be used for both treatment planning and post-treatment dosimetry. The aim of this study is to quantitatively evaluate and compare the imaging characteristics of these three isotopes, in order that imaging protocols can be optimized and RE studies with varying isotopes can be compared.Phantom experiments were performed in line with NEMA guidelines to assess the spatial resolution, sensitivity, count rate linearity, and contrast recovery of 99mTc, 90Y and 166Ho. In addition, Monte Carlo simulations were performed to obtain detailed information about the history of detected photons. The results showed that the use of a broad energy window and the high-energy collimator gave optimal combination of sensitivity, spatial resolution, and primary photon fraction for 90Y Bremsstrahlung imaging, although differences with the medium-energy collimator were small. For 166Ho, the high-energy collimator also slightly outperformed the medium-energy collimator. In comparison with 99mTc, the image quality of both 90Y and 166Ho is degraded by a lower spatial resolution, a lower sensitivity, and larger scatter and collimator penetration fractions.The quantitative evaluation of the scintillation camera characteristics presented in this study helps to optimize acquisition parameters and supports future analysis of clinical comparisons between RE studies
Phenotypic expansion in DDX3X - a common cause of intellectual disability in females
De novo variants in DDX3X account for 1-3% of unexplained intellectual disability (ID) cases and are amongst the most common causes of ID especially in females. Forty-seven patients (44 females, 3 males) have been described. We identified 31 additional individuals carrying 29 unique DDX3X variants, including 30 postnatal individuals with complex clinical presentations of developmental delay or ID, and one fetus with abnormal ultrasound findings. Rare or novel phenotypes observed include respiratory problems, congenital heart disease, skeletal muscle mitochondrial DNA depletion, and late-onset neurologic decline. Our findings expand the spectrum of DNA variants and phenotypes associated with DDX3X disorders
Clinical aspects of sentinel node biopsy
Sentinel lymph node (SLN) biopsy requires validation by a backup axillary dissection in a defined series of cases before becoming standard practice, to establish individual and institutional success rates and the frequency of false negative results. At least 90% success in finding the SLN with no more than 5-10% false negative results is a reasonable goal for surgeons and institutions learning the technique. A combination of isotope and dye to map the SLN is probably superior to either method used alone, yet a wide variety of technical variations in the procedure have produced a striking similarity of results. Most breast cancer patients are suitable for SLN biopsy, and the large majority reported to date has had clinical stage T1-2N0 invasive breast cancers. SLN biopsy will play a growing role in patients having prophylactic mastectomy, and in those with 'high-risk' duct carcinoma in situ, microinvasive cancers, T3 disease, and neoadjuvant chemotherapy. SLN biopsy for the first time makes enhanced pathologic analysis of lymph nodes logistically feasible, at once allowing greater staging accuracy and less morbidity than standard methods. Retrospective data suggest that micrometastases identified in this way are prognostically significant, and prospective clinical trials now accruing promise a definitive answer to this issue
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