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To compare physical, psychological, and physiological adaptations between rotating and morning shift health workers using objective and subjective approaches. Forty nurses [n = 20 morning shift (MS) group; n = 20 rotating shift (RS) group] were evaluated for anthropometry, body composition, and handgrip strength. Quality of life, depression, fatigue, daytime sleepiness, and sleep quality were assessed with SF-36, Zung Self-Rating Depression Scale (SDS), Fatigue Severity Scale (FSS), Epworth Sleepiness Scale (ESS), and Pittsburgh Sleep Quality Index (PSQI), respectively. Physical activity was assessed by the International Physical Activity Questionnaire (IPAQ) and triaxial accelerometers. Sleep-related data were monitored with sleep actigraphy. Salivary melatonin levels were analyzed before/after sleep, and blood lipid profiles were measured the following morning. The RS group had higher mean BMI and total and abdominal fat and scored lower in the SF-36 (p

Hemodialysis (HD) patients suffer from generalized weakness, exercise intolerance and muscle atrophy, all leading to generalized fatigue and lack of energy. HD patients spend at least 50% of their time in a functionally “switch off” mode with their fatigue sensations reaching a peak in the immediate hours after the dialysis session. The purpose of the current study was to assess the effectiveness of a nine-month hybrid intradialytic exercise program on fatigue symptoms occurring during and after hemodialysis session. Twenty stable hemodialysis patients were included in the study (59 ± 13.7 years; 16 males). All patients completed a 9-month supervised exercise training program composed of both aerobic cycling and resistance training during HD. Aspects related to physical and generalized fatigue were assessed via validated questionnaires, while physical performance was assessed by a battery of tests, before and after the intervention period. Exercise capacity and physical performance were increased by an average of 65 and 40%, respectively. Patients reported feeling better during post-dialysis hours in question 1 (p = 0.000), question 3 (p = 0.009) and question 4 (p = 0.003) after the 9-month intervention. In addition, exercise training improved scores in cognitive function (p = 0.037), vitality (p = 0.05), depression (p = 0.000) and fatigue (p = 0.039). The present study showed that a 9-month hybrid (aerobic + resistance) exercise training program improved symptoms of post-dialysis fatigue and overall general perception of fatigue. Hybrid exercise training is a safe and effective non-pharmacological approach to ameliorate fatigue symptoms in HD patients. Trial registration number The study is registered at ClinicalTrials.gov (NCT01721551, 2012) as a clinical trial.

It is well known that the luminescence efficiency of single crystals is affected by external parameters, such as the environmental temperature, especially in harsh environments. Due to this, it is of worth to examine the influence of temperature on the luminescence output of single-crystal scintillators. In this study lutetium aluminum garnet (Lu3Al5O12:Ce-LuAG:Ce) was examined, against previously published data for cadmium tungstate (CdWO4) and calcium fluoride doped with europium (CaF2:Eu) single crystals. Experiments were carried using a medical X-ray source, set to fixed high voltage (90kVp) and tube current/exposure time product (63mAs), in order to record the produced light, under different temperature conditions (20-120 Celsius). An interesting finding is that temperature, in the examined range, appear to have minimal influence on the light output of LuAG:Ce, in the contrary to the previously examined crystals (CdWO4 and CaF2:Eu) where the luminescence output constantly decreased with increasing temperature. The thermal stability of LuAG:Ce, in the examined temperature range, renders it a good choice, besides medical imaging, also for application in harsh environments as well as for long-term operation in high power LEDs.

Various studies have been conducted, exploring the genetic susceptibility of Alzheimer’s disease (AD). Adenosine receptor subtype A2a (ADORA2A) and cytochrome P450 1A2 (CYP1A2) are implicated in pathways such as oxidative stress and caffeine metabolism, which are associated with AD. The aim of this study was to explore for any potential association between the ADORA2A rs5760423 and the CYP1A2 rs762551 genetic variants and AD. A case–control study was performed with a total of 654 subjects (327 healthy controls and 327 patients with AD). Five genetic models were assumed. We also examined the allele–allele combination of both variants. The value of 0.05 was considered as the statistical significance threshold. A statistically significant association was found between ADORA2A rs5760423 and AD, as the “T” allele was associated with increased AD risk in recessive (OR = 1.51 (1.03–2.21)) and log-additive (OR = 1.30 (1.04–1.62)) genetic modes. In the codominant model, the TT genotype was more prevalent compared to the GG genotype (OR = 1.71 (1.09–2.66)). The statistical significance was maintained after adjustment for sex. No association between CYP1A2 rs762551 or allele–allele combination and AD was detected. We provide preliminary indication for a possible association between the ADORA2A rs5760423 genetic polymorphism and AD.

Background and PurposeAutomated brain volume analysis from MRI images, is gaining an important role in computer-aided diagnosis. This study compares the volumes of brain segments that measured by two automated brain analysis software: NeuroQuant and volBrain. The aim is to investigate the quantitative and qualitative reliability of automated brain analysis.MethodsWe compared same brain segment volume measurements, from 45 patients, that calculated with both NeuroQuant and volBrain software. The statistical two-tailed unpaired t-test method used to determine if there is a significant difference on the same segment measurements performed from each software. Additionally, least square method used, to provide any evidence of linear correlation between them. In a case of extreme difference, manual volume measurement of a segment was performed, with JIM8 software.ResultsFrom the comparison of brain segments volumetric measurements made by NeuroQuant and volBrain, the differences for the Intracranial Cavity, Putamen, Thalamus and Amygdala considered extremely significant, the Whole Brain, Cerebellum, Hippocampus considered not significant, White Matter considered quite significant. In most cases strong linear correlation between the two software measurements found.ConclusionsThe unexpected significant differences found in some segments raised questions about the reliability of automated volume analysis as a quantitative tool. Strong linear correlation of the volumes presents that both software finally provides good qualitative information on brain structures, which is an important factor for computed aided diagnosis.

To compare physical, psychological, and physiological adaptations between rotating and morning shift health workers using objective and subjective approaches.Forty nurses [n = 20 morning shift (MS) group; n = 20 rotating shift (RS) group] were evaluated for anthropometry, body composition, and handgrip strength. Quality of life, depression, fatigue, daytime sleepiness, and sleep quality were assessed with SF-36, Zung Self-Rating Depression Scale (SDS), Fatigue Severity Scale (FSS), Epworth Sleepiness Scale (ESS), and Pittsburgh Sleep Quality Index (PSQI), respectively. Physical activity was assessed by the International Physical Activity Questionnaire (IPAQ) and triaxial accelerometers. Sleep-related data were monitored with sleep actigraphy. Salivary melatonin levels were analyzed before/after sleep, and blood lipid profiles were measured the following morning.The RS group had higher mean BMI and total and abdominal fat and scored lower in the SF-36 (p 0.01). All nurses showed reduced physical activity levels, which, in the RS group, were negatively correlated with FSS (p = 0.033) and SDS scores (p = 0.025). Poor sleep was revealed in 53% of nurses. The RS group had worse sleep quality by PSQI than the MS group (p = 0.045). PSQI scores were inversely related to SF-36 scores and positively correlated with FSS, BMI, waist circumference, and body fat (p 0.05).RS nurses showed increased body mass and total and abdominal fat along with decreased quality of life and sleep quality compared to MS counterparts. A strong relationship was found between physical, psychological, and physiological domains. Further studies should consider workplace interventions to prevent obesity, promote physical activity, and manage poor sleeping patterns in nurses.

Purpose To visualize the meniscus of the knee joint in the axial plane and identify injuries that cannot be visualized using conventional sequences. Methods Two hundred and two subjects underwent an improvised 3-Dimensional Proton Density Fat Saturation (3D-PD FS) Magnetic Resonance (MR) sequence on their meniscus. The transverse images were reconstructed and examined. Fifty-three of the subjects had a healthy meniscus and their images were used as part of a qualitative evaluation to verify that all parts of the meniscus were properly visualized. The evaluation was based on a four-level scale indicating the visualization of meniscal parts. The same evaluation was also performed on the 149 subjects with meniscal pathologies. Another qualitative evaluation was performed on all subjects concerning five image characteristics based on a five-level scale. Finally, images from 20 patients with meniscal pathologies were compared with arthroscopic images visualizing meniscal tears. Results In all subjects, all parts of the meniscus were clearly visualized. The axial reformats provided ideal imaging of the meniscus, yielding high total image quality, satisfactory smoothing and sharpening, fewer artifacts, and successful fat saturation. The findings of the MR images from the 20 subjects with meniscal pathologies, concerning the topography of meniscal tears coincided at 100% with their arthroscopic findings. Conclusion The use of the improvised 3D-PD FS sequence provides the possibility of axial reconstruction with a better depiction of the meniscus. These images can accurately illustrate the range of the meniscus and any meniscal tears along with their exact location with high image quality.

Renal artery stenosis leading to renal damage is not uncommon among patients with abdominal aortic aneurysm and has been identified in 20–38% of patients with aortic disease. In otherwise normal renal arteries, a thrombus at the origin of the artery may decrease the renal blood flow, leading to renal colic and kidney impairment. We report a rare case of a patient with renal symptoms associated with dissecting aortic aneurysm, with thrombus at the level of the origin of an otherwise normal right renal artery.

Made available in DSpace on 2020-12-10T17:39:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-08-14 Purpose Limited data exist regarding the effects of detraining on functional capacity and quality of life (QoL) in the hemodialysis population. The aim of the current study was to assess whether the discontinuation from a systematic intradialytic exercise training program will affect aspects of health-related QoL and functional capacity in hemodialysis patients. Methods Seventeen hemodialysis patients (12 Males/5 Females, age 60.8 +/- 13.6 year) participated in this study. Patients were assessed for functional capacity using various functional capacity tests while QoL, daily sleepiness, sleep quality, depression and fatigue were assessed using validated questionnaires at the end of a 12-month aerobic exercise program and after 12 months of detraining. Results The detraining significantly reduced patients' QoL score by 20% (P = 0.01). More affected were aspects related to the physical component summary of the QoL (P < 0.001) rather than those related to the mental one (P = 0.096). In addition, the performance in the functional capacity tests was reduced (P < 0.05), while sleep quality (P = 0.020) and daily sleepiness scores (P = 0.006) were significantly worse after the detraining period. Depressive symptoms (P = 0.214) and the level of fatigue (P = 0.163) did not change significantly. Conclusions Detraining has a detrimental effect in patients' QoL, functional capacity and sleep quality. The affected physical health contributed significantly to the lower QoL score. It is crucial for the chronic disease patients, even during emergencies such as lockdowns and restrictions in activities to maintain a minimum level of activity to preserve some of the acquired benefits and maintain their health status. Sao Paulo State Univ, Biosci Inst, Rio Claro, Brazil Minist Educ Brazil, CAPES Fdn, Brasilia, DF, Brazil Univ Thessaly, Dept PE & Sport Sci, Trikala, Greece Univ Nicosia, Dept Life & Hlth Sci, Nicosia, Cyprus Univ Thessaly, Sch Hlth Sci, Dept Med, Larisa, Greece Univ West Attica, Dept Biomed Sci, Athens, Greece Plymouth Marjon Univ, Sch Sports Hlth & Wellbeing, Plymouth, Devon, England Cardiff Metropolitan Univ, Sch Sports & Hlth Sci, Cardiff, Wales Sao Paulo State Univ, Biosci Inst, Rio Claro, Brazil

The aim of this present study is to evaluate the reduction of susceptibility artifacts by increasing bandwidth (BW) and echo train length (ETL) in proton density turbo spin echo (PD TSE) sequences with and without fat saturation (FS) and in turbo inversion recovery magnitude (TIRM) sequences. We compared: (1) TIRM coronal (COR) with TIRM COR with high (H) BW and Long ETL; (2) PD TSE sagittal (SAG) FS with the PD TSE SAG FS with (H) BW; (3) PD TSE SAG with PD TSE SAG with (H) BW; (4) PD TSE SAG with PD TSE SAG with (H) BW and Long ETL. A quantitative analysis measured the extent of the susceptibility artifacts. A qualitative analysis evaluated the susceptibility artifacts, image distortion and effectiveness of fat suppression. The depiction of cartilage, menisci, muscles, tendons and bone marrow were also qualitatively analyzed. In the quantitative analysis, modified TIRM appears superior. In the qualitative analysis, the modified TIRM appears superior in 8/10 characteristics. The modified PD TSE FS is superior to the conventional regarding the susceptibility artifacts, image distortion and the depiction of bone marrow and cartilage and fat saturation. The modified PD TSE with (H) BW is found to be superior to the conventional PD TSE only in cartilage. In these sequences, when ETL was increased there were significant differences in four characteristics (ghost artifacts, cartilage, menisci and muscles). TIRM sequences with an increased BW and ETL are proposed to be used in daily clinical practice.

Both beta thalassemia and restless legs syndrome (RLS) patients share some common pathophysiological characteristics related to iron handling. In the present study, the aim was to explore the prevalence of RLS as well as to explore potential association between the syndrome and various quality of life-related parameters in a sample of beta thalassemia patients. One hundred fourteen (age 40 ± 11 yr, 59 M/55F) beta thalassemia patients participated in this cross-sectional descriptive study. Patients were screened for RLS based on the international RLS study group diagnostic criteria as well as a battery of validated questionnaires. The prevalence of RLS in this sample of beta thalassemia patients was zero. The quality of life score was low (78 ± 18). Iron levels were within normal range (191 ± 66 mcg/dL) while ferritin levels were high as expected (1836 ± 225 ng/dL). Our sample of patients comes from central Greece where the prevalence of RLS in the general population is 4% while in renal failure patients is 27%. To our surprise, there was no presence of RLS among this sample of beta thalassemia patients. The adequate levels of iron and ferritin often seen in these patients could be the reason of the absence of RLS symptoms.

The aim of this study was to investigate the modulation transfer function (MTF) and the effective gain transfer function (eGTF) of a non-destruc­­tive testing (NDT)/industrial inspection complementary metal oxide semi­conductor (CMOS) sensor in conjunction with a thin calcium tungstate (CaWO4) screen. Thin screen samples, with dimensions of 2.7x3.6 cm2 and thick­ness of 118.9 μm, estimated from scanning electron microscopy-SEM im­ages, were extracted from an Agfa Curix universal screen and coupled to the active area of an active pixel (APS) CMOS sensor. MTF was assessed using the slanted-edge method, following the IEC 62220-1-1:2015 method. MTF values were found high across the examined spatial frequency range. eGTF was found maximum when CaWO4 was combined with charge-coupled devices (CCD) of broadband anti-reflection (AR) coating (17.52 at 0 cycles/mm). The com­bi­nation of the thin CaWO4 screen with the CMOS sensor provided very pro­mis­ing image resolution and adequate efficiency properties, thus could be also con­sidered for use in CMOS based X-ray imaging devices, for various applications.

Objective This study aims at identifying, classifying, and measuring the frequency the different artifacts that show up in the images of the Sagittal T1 Fluid Attenuated Inversion Recovery (FLAIR) sequence. Materials and Methods A total of 101 subjects underwent brain magnetic resonance imaging examination with the following sequences: Axial T1 FLAIR, Axial T2-weighted imaging, Diffusion Weighted Imaging, 2D Multiple Echo Recombined Gradient Echo, Sagittal T1 FLAIR, Coronal T2 Turbo Spin Echo, Spin Echo T1-weighted imaging, and 3D Fast Spoiled Gradient-echo. In these images, we observed the following categories of artifacts: (a) ghost artifacts, (b) aliasing behind the occipital bone, (c) aliasing inside the sphenoid cavity, (d) susceptibility artifacts, and (e) pulsation artifacts. In order to recognize and verify the artifacts, we used not only the Sagittal T1 FLAIR sequence, but also Sagittal reconstructions from the 3-dimensional Fast Spoiled Gradient-echo sequence and the other routine sequences. Results Aliasing artifacts and especially aliasing of nose are present in 41% of the cases. In 45% of these cases the uncommon aliasing artifacts, which took place into the brain parenchyma (sphenoid cavity, subarachnoid bay, or pituitary) originated from nose. In 33% of the subjects, ghost artifacts are presented, which stem from the nose, the orbits, or other pulsating structures (pulsation artifacts) or even from fat tissue. Moreover, susceptibility artifacts comprise 8% of all the artifacts. Finally, 19% of brains were presented without artifact. Conclusions We suggest in addition to T1 FLAIR, the application of Sagittal SE or TSE sequences in magnetic resonance imaging examination of brain, trying to include the nose in the square of FOV.

The aim of the current study was to examine whether prolonged low-intensity aerobic exercise could affect nocturnal activity in healthy individuals. Twenty-one healthy adults (24 &plusmn, 3.7 years, 9 females) were enrolled in this study. All participants participated in a 3-h low-intensity walking exercise protocol. Standard biochemical indices were assessed before the exercise protocol and at 72 h. Nocturnal activity and various indices of health were recorded for five consecutive days. The score of muscle pain peaked the night after the exercise protocol (p &lt, 0.05) and returned to baseline two days after. No statistical differences were found in any of the parameters examined, including nocturnal activity. Prolonged low-intensity exercise does not affect nocturnal activity. The anecdotal reports suggesting that exercise or/and physical activity could worsen symptoms of motor restlessness during sleep in sleep disorders, such as restless legs syndrome and periodic limb movements, are not supported by this study. However, these findings need to be verified in clinical populations, as well as by using protocols with different forms of exercise.

The aim of the present study was to design an adaptable pattern recognition (PR) system to discriminate low- from high-grade squamous intraepithelial lesions (LSIL and HSIL, respectively) of the cervix using microscopy images of hematoxylin and eosin (H&E)-stained biopsy material from two different medical centers. Clinical material comprised H&E-stained biopsies of 66 patients diagnosed with LSIL (34 cases) or HSIL (32 cases). Regions of interest were selected from each patient’s digitized microscopy images. Seventy-seven features were generated, regarding the texture, morphology and spatial distribution of nuclei. The probabilistic neural network (PNN) classifier, the exhaustive search feature selection method, the leave-one-out (LOO) and the bootstrap validation methods were used to design the PR system and to assess its precision. Optimal PR system design and evaluation were made feasible by the employment of graphics processing unit (GPU) and Compute Unified Device Architecture (CUDA) technologies. The accuracy of the PR-system was 93% and 88.6% when using the LOO and bootstrap validation methods, respectively. The proposed PR system for discriminating LSIL from HSIL of the cervix was designed to operate in a clinical environment, having the capability of being redesigned when new verified cases are added to its repository and when data from other medical centers are included, following similar biopsy material preparation procedures.

Purpose: Acute appendicitis is a clinical emergency and is one of the more common causes of acute abdominal pain. Consequently, to avoid significant unpleasant consequences it is necessary have early diagnosis and treatment. Commonly, in patients with signs of appendicitis an abdominal computed tomography (CT) examination should be performed. Materials/methods: Out of 12 cases of patients with acute appendicitis. The presence of an appendicolith was one common finding in the CTs of those cases. Almost one third of patients show the presence of appendicoliths, which may have prognostic importance since their presence has been associated with increased likelihood for appendiceal perforation. Results: In the first case, a young adult underwent a CT examination with incomplete oral administration of contrast material. This revealed the existence of an appendicolith, which caused acute appendicitis. The second patient with acute appendicitis is an adult who was diagnosed 40 days after his CT pyelography, in which small appedicoliths were not observed. Conclusion: In cases where there is suspicion for acute appendicitis, nephrolithiasis and ureterolithiasis, it is proposed to CT scan the patient without oral contrast material. This targeted pelvis CT scan should be of low dose covering the region of cecum. Subsequently, oral and IV contrast should be administered and an enhanced CT should be acquired to succeed gastric intestinal differentiation. In this way, we can avoid covering the lower abdomen and identify better any small stones.

X-ray detectors are used in medical imaging for the representation of diagnostic information. Digital detector performance is evaluated through appropriate parameters in the spatial domain (i.e. contrast, noise or resolution) and in the frequency domain. Dental radiography is a domain of medical imaging. The purpose of this work is the examination of a commercially available digital dental imaging detector through spatial frequency domain parameters. The available detector was a commercially available image receptor SCHICK CDR, working in indirect mode that is a scintillator coupled to a Complementary Metal Oxide Semiconductor (CMOS) photoreceptor. The detector was irradiated at an X-ray system with 60 kVp and 70 kVp tube voltages utilized in intraoral radiography. The detector linearity, Modulation Transfer Function (MTF), Normalized Noise Power Spectrum (NNPS) and Detective Quantum Efficiency (DQE) were measured according to literature. The Entrance Surface Air Kerma (ESAK) was measured with an RTI PIRANHA X-ray multimeter. The images were evaluated as presented to the dentist by the detector software, in 12bit format. The resolution of the detector was found better than 100 μm. The DQE curves suggested optimum exposure conditions below 133 μGy.

Background. Cervical dysplasia is a precancerous condition, and if left untreated, it may lead to cervical cancer, which is the second most common cancer in women. The purpose of this study was to investigate differences in nuclear properties of the H&E-stained biopsy material between low CIN and high CIN cases and associate those properties with the CIN grade. Methods. The clinical material comprised hematoxylin and eosin- (H&E-) stained biopsy specimens from lesions of 44 patients diagnosed with cervical intraepithelial neoplasia (CIN). Four or five nonoverlapping microscopy images were digitized from each patient’s H&E specimens, from regions indicated by the expert physician. Sixty-three textural and morphological nuclear features were generated for each patient’s images. The Wilcoxon statistical test and the point biserial correlation were used to estimate each feature’s discriminatory power between low CIN and high CIN cases and its correlation with the advancing CIN grade, respectively. Results. Statistical analysis showed 19 features that quantify nuclear shape, size, and texture and sustain statistically significant differences between low CIN and high CIN cases. These findings revealed that nuclei in high CIN cases, as compared to nuclei in low CIN cases, have more irregular shape, are larger in size, are coarser in texture, contain higher edges, have higher local contrast, are more inhomogeneous, and comprise structures of different intensities. Conclusion. A systematic statistical analysis of nucleus features, quantified from the H&E-stained biopsy material, showed that there are significant differences in the shape, size, and texture of nuclei between low CIN and high CIN cases.

To evaluate the ability of proton-density with fat-suppression BLADE (proprietary name for periodically rotated overlapping parallel lines with enhanced reconstruction in MR systems from Siemens Healthcare, PDFS BLADE) and turbo inversion recovery magnitude-BLADE (TIRM BLADE) sequences to reduce motion and pulsation artifacts in shoulder magnetic resonance examinations. Forty-one consecutive patients who had been routinely scanned for shoulder examination participated in the study. The following pairs of sequences with and without BLADE were compared: (a) Oblique coronal proton-density sequence with fat saturation of 25 patients and (b) oblique sagittal T2 TIRM-weighed sequence of 20 patients. Qualitative analysis was performed by two experienced radiologists. Image motion and pulsation artifacts were also evaluated. In oblique coronal PDFS BLADE sequences, motion artifacts have been significantly eliminated, even in five cases of non-diagnostic value with conventional imaging. Similarly, in oblique sagittal T2 TIRM BLADE sequences, image quality has been improved, even in six cases of non-diagnostic value with conventional imaging. Furthermore, flow artifacts have been improved in more than 80% of all the cases. The use of BLADE sequences is recommended in shoulder imaging, especially in uncooperative patients because it effectively eliminates motion and pulsation artifacts.

Restless legs syndrome/Willis-Ekbom disease (RLS/WED) is a common sensorimotory disorder affecting almost 30% of hemodialysis (HD) patients. RLS/WED induces discomfort during rest hours, and its symptoms have also been observed during HD sessions. Anecdotal reports suggest that cooling the dialysate solution during dialysis could help patients overcome those symptoms and improve restlessness. The aim of this double-blind study was to assess whether a reduction of the dialysate temperature by 1°C could reduce motor and sensory symptoms of RLS/WED occurring during HD. Thirty-two HD patients participated in the study. Patients were divided into two groups: the RLS (N=16) and the non-RLS groups (N=16). Patients were studied on two different scenarios for two consecutive HD sessions, 1 week apart: 1) standard temperature of the dialysate (37°C) and 2) low temperature of the dialysate (36°C cold dialysis scenario). In all sessions, motor (leg movement per hour of HD [LM/hHD]) and sensory symptoms were assessed. The reduction of dialysate temperature by 1°C was effective in reducing motor symptoms as they assessed the LM/hHD by 36% only in patients with RLS, while a significant interaction was found between "LM/hHD affected by temperature" and "RLS status" (p = 0.039). Sensory symptoms also reduced by 10% after the reduction of the dialysate temperature. The reduction of the dialysate temperature by 1°C reduced motor symptoms by 36-54% and sensory symptoms by 10% in HD patients with RLS/WED. Cold dialysis could be considered a safe nonpharmacological approach for the amelioration of RLS/WED symptoms occurring during HD.

Purpose To evaluate T1-weighted fast spin echo (FSE) and fast T1-weighted fluid-attenuated inversion recovery (FLAIR) imaging, pre and post contrast administration, and assess the necessity of fat saturation regarding normal anatomical structures, degenerative and pathological vertebral body lesions of the spine at 3.0 T. Methods and Materials Spine magnetic resonance imaging studies of 59 consecutive patients (31 females, 28 males), aged 33–81 years (mean age 53 years) were reviewed. Qualitative and quantitative evaluation was performed by comparing T1-FSE and fast T1-weighted FLAIR after administration of a gadolinium (Gd)-based contrast agent (0.1 mmol/kg gadopentetate dimeglumine) with fat suppression (FS), detecting the sequence that provided better identification of the normal anatomical structures, as well as pathological findings. In a small sample of twelve patients, post-contrast T1-weighted images with and without FS were also included. Results On both quantitative and qualitative analysis between of T1-weighted FLAIR and T1-weighted FSE images, the FLAIR sequence with contrast administration and FS, demonstrated improved enhancement in all abnormalities, presented with minimal susceptibility artifacts, homogeneities in fat saturation for all FOV and minimal chemical shift artifacts. Conclusion Based on the results of our qualitative and quantitative assessment of the cervical, thoracic and lumbar spine at 3.0T we concluded that fast T1-weighted FLAIR images with intravenous (iv) Gd and FS were superior to T1-weighted FSE images with iv Gd and FS, with respect to identification of normal anatomical structures and pathology.

The purpose of this retrospective clinical study was to identify and evaluate the presence and frequency of T2 FLAIR artifacts on brain MRI studies performed at 3 T. We reviewed axial T2 FLAIR images in 200 consecutive unremarkable brain MRI studies performed at 3 T. All studies were reviewed for the presence of artifacts caused by pulsatile CSF flow, magnetic susceptibility and no nulling of the CSF signal. T2 FLAIR images introduce several artifacts that may degrade image quality and mimic pathology. Knowledge of these artifacts and increased severity and frequency at 3 T is of particular importance in avoiding a misdiagnosis.

Objectives In the present work, we aim to identify changes in the cartilage texture of the injured knee in young, physically active, patients by computer analysis of MRI images based on 3.0 T morphological sequences. Methods Fifty-three young patients with training injury or trauma in one knee underwent MRI and arthroscopy. Textural features were computed from the MRI images of the knee-cartilages and two classes were formed of 28 normal and 16 with pathology only in the medial femoral condyle (MFC) cartilage. Results Textural features with statistically significant differences between the two classes were found only at the MFC and the medial tibial condyle (MTC) areas. Three features-combinations, at the MFC or the MTC, maximized the between classes separation, thus, rendering alterations in cartilage texture due to injury more evident. The MFC cartilage in the pathology class was found more inhomogeneous in the distribution of gray-levels and of lower texture anisotropy and the opposed MTC cartilage, though normal on MRI and arthroscopy, was found to have lower texture anisotropy than cartilage in the normal class. Conclusion Texture analysis may be used as an adjunct to morphological MR imaging for improving the detection of subtle cartilage changes and contributes to early therapeutic approach.

The purpose of the present study was to evaluate the visibility and the image quality of the biliary and pancreatic duct system on magnetic resonance cholangiopancreatography (MRCP) images based on two breath-hold (BH) methods using array spatial sensitivity technique: a single-shot fast spin-echo (SS-FSE) sequence and a three-dimensional single slab fast spin-echo (3D-FSE) sequence.In the present prospective comparative study, 47 patients (22 male and 25 female, mean age=50 years, age range=22-82 years) that were referred for MRCP during a 12-month period are included. All of them were referred with suspected pancreaticobiliary disease. All patients underwent MRCP with both a SS-FSE BH sequence and a 3D-FSE BH sequence. Qualitative evaluation regarding the depiction of three segments of the pancreaticobiliary tree and the frequency of artifacts was performed. Two radiologists graded each sequence of the obtained studies in a blinded fashion. Quantitative evaluation including calculation of relative signal intensity (rSI) and relative contrast (RC) ratios at seven segments of the pancreaticobiliary tree between fluid-filled ductal structures and organ parenchyma at the same ductal segments was performed. In order to evaluate the parameters' differences of the two sequences, either in qualitative or in quantitative analysis, the Wilcoxon paired signed-rank test was performed.On quantitative evaluation, both rSI and RC ratios of all segments of the pancreaticobiliary tree at SS-FSE BH sequence were higher than those at 3D-FSE BH sequences. This finding was statistically significant (P.01). On qualitative evaluation, the two radiologists found intrahepatic ducts and pancreatic ducts to be better visualized with SS-FSE BH than with 3D-FSE BH sequence. This finding was statistically significant (P.02). One of them found extrahepatic ducts to be significantly better visualized with SS-FSE BH sequence. Moreover, the frequency of artifacts was lower in the SS-FSE sequence, a finding that was of statistical significance. Interobserver agreement analysis found at least substantial agreement (κ0.60) between the two radiologists.The SS-FSE sequence is performed faster and significantly improves image quality; thus, it should be included into the routine MRCP sequence protocol at 3.0 T. Furthermore, we recommended SS-FSE BH MRCP examination to be applied to uncooperative patients or patients in emergency because of its short acquisition time (1 s).

The purpose of this study is to evaluate the ability of T2 turbo spin echo (TSE) axial and sagittal BLADE sequences in reducing or even eliminating motion, pulsatile flow and cross-talk artifacts in lumbar spine MRI examinations. Forty four patients, who had routinely undergone a lumbar spine examination, participated in the study. The following pairs of sequences with and without BLADE were compared: a) T2 TSE Sagittal (SAG) in thirty two cases, and b) T2 TSE Axial (AX) also in thirty two cases. Both quantitative and qualitative analyses were performed based on measurements in different normal anatomical structures and examination of seven characteristics, respectively. The qualitative analysis was performed by experienced radiologists. Also, the presence of image motion, pulsatile flow and cross-talk artifacts was evaluated. Based on the results of the qualitative analysis for the different sequences and anatomical structures, the BLADE sequences were found to be significantly superior to the conventional ones in all the cases. The BLADE sequences eliminated the motion artifacts in all the cases. In our results, it was found that in the examined sequences (sagittal and axial) the differences between the BLADE and conventional sequences regarding the elimination of motion, pulsatile flow and cross-talk artifacts were statistically significant. In all the comparisons, the T2 TSE BLADE sequences were significantly superior to the corresponding conventional sequences regarding the classification of their image quality. In conclusion, this technique appears to be capable of potentially eliminating motion, pulsatile flow and cross-talk artifacts in lumbar spine MR images and producing high quality images in collaborative and non-collaborative patients.

In breast cancer radiotherapy, significant discrepancies in dose delivery can contribute to underdosage of the tumor or overdosage of normal tissue, which is potentially related to a reduction of local tumor control and an increase of side effects. To study the impact of these factors in breast cancer radiotherapy, a meta analysis of the clinical data reported by Mavroidis et al. (2002) in Acta Oncol (41:471–85), showing the patient setup and breathing uncertainties characterizing three different irradiation techniques, were employed. The uncertainties in dose delivery are simulated based on fifteen breast cancer patients (5 mastectomized, 5 resected with negative node involvement (R-) and 5 resected with positive node involvement (R+)), who were treated by three different irradiation techniques, respectively. The positioning and breathing effects were taken into consideration in the determination of the real dose distributions delivered to the CTV and lung in each patient. The combined frequency distributions of the positioning and breathing distributions were obtained by convolution. For each patient the effectiveness of the dose distribution applied is calculated by the Poisson and relative seriality models and a set of parameters that describe the dose-response relations of the target and lung. The three representative radiation techniques are compared based on radiobiological measures by using the complication-free tumor control probability, P+ and the biologically effective uniform dose, D̿ concepts. For the Mastectomy case, the average P+ values of the planned and delivered dose distributions are 93.8% for a D̿CTV of 51.8 Gy and 85.0% for a D̿CTV of 50.3 Gy, respectively. The respective total control probabilities, PB values are 94.8% and 92.5%, whereas the corresponding total complication probabilities, PI values are 0.9% and 7.4%. For the R- case, the average P+ values are 89.4% for a D̿CTV of 48.9 Gy and 88.6% for a D̿CTV of 49.0 Gy, respectively. The respective PB values are 89.8% and 89.9%, whereas the corresponding PI values are 0.4% and 1.2%. For the R+ case, the average P+ values are 86.1% for a D̿CTV of 49.2 Gy and 85.5% for a D̿CTV of 49.1 Gy, respectively. The respective PB values are 90.2% and 90.1%, whereas the corresponding PI values are 4.1% and 4.6%. The combined effects of positioning uncertainties and breathing can introduce a significant deviation between the planned and delivered dose distributions in lung in breast cancer radiotherapy. The positioning and breathing uncertainties do not affect much the dose distribution to the CTV. The simulated delivered dose distributions show larger lung complication probabilities than the treatment plans. This means that in clinical practice the true expected complications are underestimated. Radiation pneumonitis of Grade 1–2 is more frequent and any radiotherapy optimization should use this as a more clinically relevant endpoint.

Introduction Although T1 weighted spin echo (T1W SE) images are widely used to study anatomical details and pathologic abnormalities of the brain, its role in delineation of lesions and reduction of artifacts has not been thoroughly investigated. BLADE is a fairly new technique that has been reported to reduce motion artifacts and improve image quality. Objective The primary objective of this study is to compare the quality of T1-weighted fluid attenuated inversion recovery (FLAIR) images with BLADE technique (T1W FLAIR BLADE) and the quality of T1W SE images in the MR imaging of the brain. The goal is to highlight the advantages of the two sequences as well as which one can better reduce flow and motion artifacts so that the imaging of the lesions will not be impaired. Materials and methods Brain examinations with T1W FLAIR BLADE and T1W SE sequences were performed on 48 patients using a 1.5 T scanner. These techniques were evaluated by two radiologists based on: a) a qualitative analysis i.e. overall image quality, presence of artifacts, CSF nulling; and b) a quantitative analysis of signal-to-noise ratios (SNR), contrast-to-noise ratios (CNR) and Relative Contrast. The statistical analysis was performed using the Kruskal-Wallis non-parametric system. Results In the qualitative analysis, BLADE sequences had a higher scoring than the conventional sequences in all the cases. The overall image quality was better on T1W FLAIR BLADE. Motion and flow-related artifacts were lower in T1W FLAIR BLADE. Regarding the SNR measurements, T1W SE appeared to have higher values in the majority of cases, whilst T1W-FLAIR BLADE had higher values in the CNR and Relative Contrast measurements. Conclusion T1W FLAIR BLADE sequence appears to be superior to T1W SE in overall image quality and reduction of motion and flow-pulsation artifacts as well as in nulling CSF and has been preferred by the clinicians. T1W FLAIR BLADE may be an alternative approach in brain MRI imaging.

Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) with gadolinium constitutes one of the most promising protocols for boosting up the sensitivity in breast cancer detection. The aim of this study was twofold: first to design an image processing methodology to estimate the vascularity of the breast region in DCE-MRI images and second to investigate whether the differences in the composition/texture and vascularity of normal, benign and malignant breasts may serve as potential indicators regarding the presence of the disease. Clinical material comprised thirty nine cases examined on a 3.0-T MRI system (SIGNA HDx; GE Healthcare). Vessel segmentation was performed using a custom made modification of the Seeded Region Growing algorithm that was designed in order to identify pixels belonging to the breast vascular network. Two families of features were extracted: first, morphological and textural features from segmented images in order to quantify the extent and the properties of the vascular network; second, textural features from the whole breast region in order to investigate whether the nature of the disease causes statistically important changes in the texture of affected breasts. Results have indicated that: (a) the texture of vessels presents statistically significant differences (p

The aim of this study was to employ state-of-art graphics processing unit (GPU) technology and CUDA parallel programming to design and implement a stand-alone pattern recognition (PR) system to discriminate between patients with micro-ischaemic (mIS) and multiple sclerosis (MS) lesions. The dataset comprised MRI image series of 32 patients with mIS and 19 with MS lesions. The probabilistic neural network classifier and 40 textural features, calculated from lesions in the magnetic resonance imaging (MRI) images, were used to design the PR system. The highest classification accuracy was 90.2%, employing six textural features. It took about 135 minutes to design the PR system on a desktop CPU (Intel Core 2 Quad Q9550), using sequential programming, against 250 seconds on the Nvidia 8800GT GPU card, using parallel programming. The proposed PR system may be redesigned on site, when new verified data are incorporated in its depository, and it may serve as a second opinion tool in a clinical environment.

Restless legs syndrome (RLS) is very common in hemodialysis patients. RLS induces motor excitability and discomfort during rest periods, and those symptoms have also been observed during hemodialysis sessions. The aim of the study was to assess whether a single bout of exercise could reduce periodic limb movements (PLM) occurring during hemodialysis. Eighteen hemodialysis patients were eligible and participated in the study. Using the RLS criteria and further verified by the presence of PLM during sleep, patients were divided to non-RLS and RLS groups. Three scenarios were studied during three different sessions: 1) light exercise, including cycling for 45 minutes with no added resistance, 2) heavy exercise, including cycling for 45 minutes with a resistance set at 60% of their exercise capacity, and 3) no exercise, including rest for the same period of time. In all sessions, PLM per hour of hemodialysis (PLM/hHD) was recorded. A single bout of either light or heavy exercise was equally effective in significantly reducing PLM/hHD in patients with RLS compared with the no-exercise scenario, whereas in non-RLS patients, no effect was observed. Independent of intensity, a single bout of intradialytic exercise reduces PLM/hHD in hemodialysis patients with RLS. Further research is needed to establish the acute role of exercise in ameliorating the RLS symptoms.

Background: T1-weighted fluid-attenuated inversion recovery (FLAIR) sequence has been reported to provide improved contrast between lesions and normal anatomical structures compared to T1-weighted fast spin-echo (FSE) imaging at 1.5T regarding imaging of the lumbar spine. Purpose: To compare T1-weighted FSE and fast T1-weighted FLAIR imaging in normal anatomic structures and degenerative and metastatic lesions of the lumbar spine at 3.0T. Material and Methods: Thirty-two consecutive patients (19 females, 13 males; mean age 44 years, range 30–67 years) with lesions of the lumbar spine were prospectively evaluated. Sagittal images of the lumbar spine were obtained using T1-weighted FSE and fast T1-weighted FLAIR sequences. Both qualitative and quantitative analyses measuring the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and relative contrast (ReCon) between degenerative and metastatic lesions and normal anatomic structures were conducted, comparing these sequences. Results: On quantitative evaluation, SNRs of cerebrospinal fluid (CSF), nerve root, and fat around the root of fast T1-weighted FLAIR imaging were significantly lower than those of T1-weighted FSE images ( P Conclusion: The T1-weighted FLAIR sequence may be considered as the preferred lumbar spine imaging sequence compared to T1-weighted FSE, as it has demonstrated superior CSF nulling, better conspicuousness of normal anatomic structures and degenerative and metastatic lesions, and improved image contrast.

Purpose To explore the correlation of morphological and kinetic DCE-MRI features with histopathological prognostic factors of invasive breast cancer. Material and methods Fifty-one women with 57 cancerous lesions underwent DCE-MRI prior to surgery. DCE-MRI findings were interpreted with a multifactorial classification system that included morphological (shape, margins and pattern of enhancement) and kinetic characteristics (initial signal increase and post-initial behaviour of the time-signal intensity curve). Each morphological and kinetic parameter was scored with 0, 1 or 2 points and the total score was estimated. Finally each lesion was classified into one of the five categories that correspond to the five ACR BI-RADS categories. Statistical analysis was performed to correlate DCE-MR imaging parameters and histopathological findings using Fisher's exact test and stepwise multiple regression analysis. Results Increase of the signal intensity at the initial phase >100% was strongly correlated with positive lymph nodes (p = 0.008, OR 0.054). Types I and II time-signal intensity curves at the post-initial phase were associated with a fourfold increase in the likelihood of progesterone receptors positivity (p = 0.022, OR 4). Finally, high total score was positively correlated with affected lymph nodes (p = 0.033, OR 0.29). There was a trend regarding ill-defined margins of the tumor (p = 0.08) and vascular infiltration and also high score and neural infiltration (p = 0.072). Conclusion A multivariate interpretation model for DCE-MRI that includes morphological and kinetic characteristics has prognostic value for invasive breast cancer. Early initial contrast agent uptake and a high overall score are associated with poor prognostic factors.

Sleep apnoea frequently affects patients with end-stage renal disease. However, it is still unclear whether or to what extent sleep disorders may affect functional capacity and quality of life in haemodialysis patients. We tested the hypothesis that apneic dialysis patients due to the lack of restorative sleep will have a further reduced functional capacity and further compromised quality of life compared to their non-apneic counterparts.Forty-three clinically stable haemodialysis patients (13 F, 56.6+/-19.4 years) were examined. After polysomnographic analysis, patients were divided in two groups according to their calculated apnoea hypopnoea index (AHI; cutoff 5). Primary outcomes were intergroup differences in the following: (1) physical capacity and muscle performance, assessed by functional tests, (2) quality of life, assessed by the SF-36, (3) body composition, measured by DEXA and (4) muscle composition and size, as well as (5) visceral (VAT) and subcutaneous (SAT) adipose tissue, calculated by computed tomography.Twenty-two patients had AHI5 (4 F, AHI=28.8+/-22.3). The adjusted analysis for age, BMI and years in dialysis therapy, showed that the low-AHI group (N=21, 9 F, AHI=1.8+/-1.3) had better functional capacity, and performed better in muscle strength and endurance tests compared to the high-AHI group. There were no differences in lean body mass and % total body fat between groups, however, values for VAT, VAT/TAT ratio and thigh muscles' fat infiltration were increased in the high-AHI group. VAT correlated with BMI (r=0.682, P=0.001), functional capacity (r=0.558, P=0.001) apnoea hypopnoea index (r=0.530, P=0.001). There were no statistical significant differences in quality of life between the two groups. To further account for age and BMI differences, a subgroup of patients was matched by age, sex and BMI (N=10/group). In the matched analysis, all the above statistical differences remained, between the low-AHI and high-AHI groups.Haemodialysis patients with sleep apnoea syndrome demonstrate poorer functional capacity, physical performance and muscle composition, compared to non-apneic dialysis patients. Overall, sleep apnoea appears to partly contribute to the total diminished functional capacity of haemodialysis patients.

Digital processing of MRI images aims to provide an automatized diagnostic evaluation of regular health screenings. Cancerous lesions are proven to cause an alteration in the vessel structure of the diseased organ. Currently there are several methods used for extraction of the vessel network in order to quantify its properties. In this work MRI images (Signa HDx 3.0T, GE Healthcare, courtesy of University Hospital of Larissa) of 30 female breasts were subjected to three different vessel extraction algorithms to determine the location of their vascular network. The first method is an experiment to build a graph over known points of the vessel network; the second algorithm aims to determine the direction and diameter of vessels at these points; the third approach is a seed growing algorithm, spreading selection to neighbors of the known vessel pixels. The possibilities shown by the different methods were analyzed, and quantitative measurements were performed. The data provided by these measurements showed no clear correlation with the presence or malignancy of tumors, based on the radiological diagnosis of skilled physicians.

The aim of the current work was to assess the resolution properties of a calcium tungstate (CaWO4) screen (screen coating thickness: 50.09 mg/cm2, actual thickness: 167.2 μm) coupled to a high resolution complementary metal oxide semiconductor (CMOS) digital imaging sensor. A 2.7x3.6 cm2 CaWO4 sample was extracted from an Agfa Curix universal screen and was coupled directly with the active area of the active pixel sensor (APS) CMOS sensor. Experiments were performed following the new IEC 62220-1-1:2015 International Standard, using an RQA-5 beam quality. Resolution was assessed in terms of the Modulation Transfer Function (MTF), using the slanted-edge method. The CaWO4/CMOS detector configuration was found with linear response, in the exposure range under investigation. The final MTF was obtained through averaging the oversampled edge spread function (ESF), using a custom-made software developed by our team, according to the IEC 62220-1-1:2015. Considering the renewed interest in calcium tungstate for various applications, along with the resolution results of this work, CaWO4 could be also considered for use in X-ray imaging devices such as charged-coupled devices (CCD) and CMOS.

Purpose: The aim of that work is to study the theoretical behavior and merits of the Generalized Gamma (generalized dose response gradient) as well as to investigate the usefulness of this concept in practical radiobiological treatment planning.Methods: In this study, the treatment planning system RayStation 1.9 (Raysearch Laboratories AB, Stockholm, Sweden) was used. Furthermore, radiobiological models that provide the tumor control probability (TCP), normal tissue complication probability (NTCP), complication-free tumor control probability (P+) and the Generalized Gamma were employed. The Generalized Gammas of TCP and NTCP, respectively were calculated for given heterogeneous dose distributions to different organs in order to verify the TCP and NTCP computations of the treatment planning system. In this process, a treatment plan was created, where the target and the organs at risk were included in the same ROI in order to check the validity of the system regarding the objective function P+ and the Generalized Gamma. Subsequently, six additional treatment plans were created with the target organ and the organs at risk placed in the same or different ROIs. In these plans, the mean dose was increased in order to investigate the behavior of dose change on tissue response and on Generalized Gamma before and after the change in dose. By theoretically calculating these quantities, the agreement of different theoretical expressions compared to the values that the treatment planning system provides could be evaluated. Finally, the relative error between the real and approximate response values using the Poisson and the Probit models, for the case of having a target organ consisting of two compartments in a parallel architecture and with the same number of clonogens could be investigated and quantified. Results: The computations of the RayStation regarding the values of the Generalized Gamma and the objective function (P+) were verified by using an independent software. Furthermore, it was proved that after a small change in dose, the organ that is being affected most is the organ with the highest Generalized Gamma. Apart from that, the validity of the theoretical expressions that describe the change in response and the associated Generalized Gamma was verified but only for the case of small change in dose. Especially for the case of 50% TCP and NTCP, the theoretical values (ΔPapprox.) and those calculated by the RayStation show close agreement, which proves the high importance of the D50 parameter in specifying clinical response levels. Finally, the presented findings show that the behavior of ΔPapprox. looks sensible because, for both of the models that were used (Poisson and Probit), it significantly approaches the real ΔP around the region of 37% and 50% response. The present study managed to evaluate the mathematical expression of Generalized Gamma for the case of non-uniform dose delivery and the accuracy of the RayStation to calculate its values for different organs. Conclusion: A very important finding of this work is the establishment of the usefulness and clinical relevance of Generalized Gamma. That is because it gives the planner the opportunity to precisely determine which organ will be affected most after a small increase in dose and as a result an optimal treatment plan regarding tumor control and normal tissue complications can be found.