Thermal insulation does not hamper assessment of injuries in trauma CT scans.

PURPOSE: The use of thermal insulations reduces the risk of hypothermia, therefore decreases the risk of death in trauma victims. The aim of the study was to assess whether thermal insulations cause artifacts, which may hinder the diagnosis of injuries, and how the used thermo-systems alter the radiation dose in polytrauma computed tomography. METHODS: Computed tomography scans were made using the road accident victim body wrapped consecutively with 7 different covers. 14 injury areas were listed and evaluated by 22 radiologists. The radiation dose was measured using a dosimeter placed on the victim in the abdominal area. RESULTS: No significant artifacts in any of the tested covers were observed. The presence of few minor artifacts did not hinder the assessment of injuries. Certain materials increased (up to 19,1%) and some decreased (up to -30,3%) the absorbed radiation dose. CONCLUSIONS: Thermal insulation systems tested in this study do not cause significant artifacts hindering assessment of injuries in CT scans. Concern for artifacts and increased radiation dose should not be a reason to remove patients' thermal insulation during performing trauma CT-scanning.

Association of Blood Metabolomics Biomarkers with Brain Metabolites and Patient-Reported Outcomes as a New Approach in Individualized Diagnosis of Schizophrenia.

Given its polygenic nature, there is a need for a personalized approach to schizophrenia. The aim of the study was to select laboratory biomarkers from blood, brain imaging, and clinical assessment, with an emphasis on patients' self-report questionnaires. Metabolomics studies of serum samples from 51 patients and 45 healthy volunteers, based on the liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS/MS), led to the identification of 3 biochemical indicators (cortisol, glutamate, lactate) of schizophrenia. These metabolites were sequentially correlated with laboratory tests results, imaging results, and clinical assessment outcomes, including patient self-report outcomes. The hierarchical cluster analysis on the principal components (HCPC) was performed to identify the most homogeneous clinical groups. Significant correlations were noted between blood lactates and 11 clinical and 10 neuroimaging parameters. The increase in lactate and cortisol were significantly associated with a decrease in immunological parameters, especially with the level of reactive lymphocytes. The strongest correlations with the level of blood lactate and cortisol were demonstrated by brain glutamate, N-acetylaspartate and the concentrations of glutamate and glutamine, creatine and phosphocreatine in the prefrontal cortex. Metabolomics studies and the search for associations with brain parameters and self-reported outcomes may provide new diagnostic evidence to specific schizophrenia phenotypes.

The value of lung ultrasound in COVID-19 pneumonia, verified by high resolution computed tomography assessed by artificial intelligence.

BACKGROUND: Lung ultrasound (LUS) is an increasingly popular imaging method in clinical practice. It became particularly important during the COVID-19 pandemic due to its mobility and ease of use compared to high-resolution computed tomography (HRCT). The objective of this study was to assess the value of LUS in quantifying the degree of lung involvement and in discrimination of lesion types in the course of COVID-19 pneumonia as compared to HRCT analyzed by the artificial intelligence (AI). METHODS: This was a prospective observational study including adult patients hospitalized due to COVID-19 in whom initial HRCT and LUS were performed with an interval < 72 h. HRCT assessment was performed automatically by AI. We evaluated the correlations between the inflammation volume assessed both in LUS and HRCT, between LUS results and the HRCT structure of inflammation, and between LUS and the laboratory markers of inflammation. Additionally we compared the LUS results in subgroups depending on the respiratory failure throughout the hospitalization. RESULTS: Study group comprised 65 patients, median 63 years old. For both lungs, the median LUS score was 19 (IQR-interquartile range 11-24) and the median CT score was 22 (IQR 16-26). Strong correlations were found between LUS and CT scores (for both lungs r = 0.75), and between LUS score and percentage inflammation volume (PIV) (r = 0.69). The correlations remained significant, if weakened, for individual lung lobes. The correlations between LUS score and the value of the percentage consolidation volume (PCV) divided by percentage ground glass volume (PGV), were weak or not significant. We found significant correlation between LUS score and C-reactive protein (r = 0.55), and between LUS score and interleukin 6 (r = 0.39). LUS score was significantly higher in subgroups with more severe respiratory failure. CONCLUSIONS: LUS can be regarded as an accurate method to evaluate the extent of COVID-19 pneumonia and as a promising tool to estimate its clinical severity. Evaluation of LUS in the assessment of the structure of inflammation, requires further studies in the course of the disease. TRIAL REGISTRATION: The study has been preregistered 13 Aug 2020 on clinicaltrials.gov with the number NCT04513210.

Artificial intelligence guided HRCT assessment predicts the severity of COVID-19 pneumonia based on clinical parameters.

BACKGROUND: The purpose of the study was to compare the results of AI (artificial intelligence) analysis of the extent of pulmonary lesions on HRCT (high resolution computed tomography) images in COVID-19 pneumonia, with clinical data including laboratory markers of inflammation, to verify whether AI HRCT assessment can predict the clinical severity of COVID-19 pneumonia. METHODS: The analyzed group consisted of 388 patients with COVID-19 pneumonia, with automatically analyzed HRCT parameters of volume: AIV (absolute inflammation), AGV (absolute ground glass), ACV (absolute consolidation), PIV (percentage inflammation), PGV (percentage ground glass), PCV (percentage consolidation). Clinical data included: age, sex, admission parameters: respiratory rate, oxygen saturation, CRP (C-reactive protein), IL6 (interleukin 6), IG - immature granulocytes, WBC (white blood count), neutrophil count, lymphocyte count, serum ferritin, LDH (lactate dehydrogenase), NIH (National Institute of Health) severity score; parameters of clinical course: in-hospital death, transfer to the ICU (intensive care unit), length of hospital stay. RESULTS: The highest correlation coefficients were found for PGV, PIV, with LDH (respectively 0.65, 0.64); PIV, PGV, with oxygen saturation (respectively - 0.53, -0.52); AIV, AGV, with CRP (respectively 0.48, 0.46); AGV, AIV, with ferritin (respectively 0.46, 0.45). Patients with critical pneumonia had significantly lower oxygen saturation, and higher levels of immune-inflammatory biomarkers on admission. The radiological parameters of lung involvement proved to be strong predictors of transfer to the ICU (in particular, PGV ≥ cut-off point 29% with Odds Ratio (OR): 7.53) and in-hospital death (in particular: AIV ≥ cut-off point 831 cm3 with OR: 4.31). CONCLUSIONS: Automatic analysis of HRCT images by AI may be a valuable method for predicting the severity of COVID-19 pneumonia. The radiological parameters of lung involvement correlate with laboratory markers of inflammation, and are strong predictors of transfer to the ICU and in-hospital death from COVID-19. TRIAL REGISTRATION: National Center for Research and Development CRACoV-HHS project, contract number SZPITALE-JEDNOIMIENNE/18/2020.

Dual energy computed tomography in differentiation of iodine contrast agent staining from secondary brain haemorrhage in patients with ischaemic stroke treated with thrombectomy.

INTRODUCTION: The aim of this study was to assess the value of dual energy computed tomography (DECT) in the differentiation of iodine contrast agent staining from secondary brain haemorrhage in patients with acute ischaemic stroke treated with mechanical thrombectomy. MATERIAL AND METHODS: The group analysed consisted of 66 hyperdense areas in 64 patients with acute ischaemic stroke treated with mechanical thrombectomy and controlled in DECT performed within the first 24 hours after thrombectomy. In every area both qualitative and quantitative analysis of iodine and water material density (MD) maps was performed for the differentiation of iodine and blood, as well as CT density analysis. RESULTS: 66.7% of hyperdense areas were classified as iodine, 18.2% as iodine + blood, and 15.1% as blood. The density of iodine was significantly higher in the iodine (median 9.64 100ug/cm3) group compared to the blood (median 3.97 100ug/cm3) and iodine + blood (median 7.57 100ug/cm3) groups. The density of water was significantly higher in the blood (median 1,051.50 mg/cm3) and iodine + blood (median 1,038.00 mg/cm3) groups compared to the iodine (median 1,021.00 mg/cm3) group. CONCLUSIONS: DECT with iodine-water material decomposition maps is a valuable tool in the differentiation of prolonged staining of iodine contrast agent from secondary brain haemorrhage in patients with acute ischaemic stroke treated with mechanical thrombectomy. The value of 6 100ug/cm3 (0.6 mg/cm3) seems a good threshold in quantitative differentiation of iodine from blood on iodine (water) MD maps. The value of 1,030 mg/cm3 seems a good threshold in quantitative differentiation of iodine from blood on water (iodine) MD maps.

Mechanical thrombectomy in COVID-19-associated ischaemic stroke: patient characteristics and outcomes in a single-centre study.

INTRODUCTION: The aim of this study was to assess the clinical profiles and outcomes of patients with confirmed COVID-19 infection and acute ischaemic stroke (AIS) treated with mechanical thrombectomy (MT) at the Comprehensive Stroke Centre (CSC) of the University Hospital in Krakow. CLINICAL RATIONALE FOR THE STUDY: COVID-19 is a risk factor for AIS and worsens prognosis in patients with large artery occlusions. During the pandemic, the global number of MT has dropped. At the same time, studies assessing outcomes of this treatment in COVID-19-associated AIS have produced divergent results. MATERIAL AND METHODS: In this single-centre study, we retrospectively analysed and compared the clinical profiles (age, sex, presence of cardiovascular risk factors, neurological deficit at admission), stroke size (measured using postprocessing analysis of perfusion CT with RAPID software), time from stroke onset to arrival at the CSC, time from arrival at the CSC to groin puncture, treatment with intravenous thrombolysis, length of hospitalisation, laboratory test results, and short-term outcomes (measured with Thrombolysis in Cerebral Infarction scale, modified Rankin Scale and National Health Institute Stroke Scale) in patients with AIS treated with MT during the pandemic. A comparison between patients with and without concomitant SARS-CoV2 infection was then performed. RESULTS: There were no statistically significant differences between 15 COVID (+) and 167 COVID (-) AIS patients treated with AIS with respect to clinical profiles (p > 0.05), stroke size (p > 0.05) or outcomes (NIHSS at discharge, 8.1 (SD = 7.1) vs. 8.8 (SD = 9.6), p = 0.778, mRS at discharge 2.9 (SD = 2) vs. 3.1 (SD = 2.1), p = 0.817, death rate 6.7% vs. 12.6%, p = 0.699). There was a significant difference between patients with and without COVID-19 concerning time from arrival at the CSC to groin puncture [104.27 (SD = 51.47) vs. 97.63 (SD = 156.94) min., p = 0.044] and the length of hospitalisation [23.7 (SD = 11.9) vs. 10.5 (SD = 6.9) days, p < 0.001]. CONCLUSION: In AIS patients treated with MT, concomitant SARS-CoV2 infection did not affect the outcome. Our observations need to be confirmed in larger, and preferably multicentre, studies.

Clinical utility of brain computed tomography in prediction of post-stroke delirium.

Delirium is a common and serious complication of stroke. Early prediction of delirium is important for preventive strategies and close monitoring of high-risk patients. Pre-existing degenerative and vascular changes in the brain could predispose to delirium. We aimed to determine if computed tomography (CT)-based indices could provide additional information about a risk of stroke-associated delirium beyond easiest-to-access clinical predictors. Using semi-quantitative scales (global cortical atrophy, age-related white matter changes, and Scheltens scale), we assessed global and regional brain atrophy and white matter changes in 88 stroke patients with delirium and 142 patients without delirium matched for age and stroke severity. Patients with delirium had greater global and local brain atrophy (the right temporal region, the left parieto-occipital region, the right frontal and occipital horn, and the right and left temporal horn) than patients without delirium. Scores of white matter changes did not differ between groups with exception of greater white matter damage in the right parieto-occipital area in patients with delirium. The discriminatory properties of studied radiological indices were modest (areas under receiver operator curves: 0.58-0.64). CT-based indices of brain atrophy and white matter changes do not provide additional information about a risk of post-stroke delirium beyond the most important clinical predictors.

The course of the main septum in the sphenoid sinuses - evaluation before the FESS.

The purpose of this study was to determine the course of the main septum (MS) in the sphenoid sinuses in the adult population. Materials and Methods: 296 patients (147 females, 149 males), who did not present any pathology in the paranasal sinuses, were included in this retrospective analysis of the computed tomography (CT) scans. Spiral CT scanner (Siemens Somatom Sensation 16) was used in order to glean the images of the paranasal sinuses, using standard procedure, in the option Siemens CARE Dose 4D, without using any contrast medium. Secondary reconstructions of the sagittal and frontal planes were obtained using multi- plans reconstruction (MPR) tool after obtaining transverse planes in the first instance. R e s u l t s: The course of the MS changed the most often from the anterior to the posterior part of the sphenoid sinuses. Such situation took place in 83.78% of the patients, in 32.43% of whom a clear shift to the lateral side was noticed only in the posterior part of the MS: in 18.24% of the patients to the right side, and in 14.19% of the patients to the left side. In 17.57% of the patients the lateral shift was visible in both anterior and posterior parts of the septum, where in 9.46% of the patients it was from the left side to the right, whereas in 8.11% of the patients the shift took place from the right side to the left. The MS had the shape of the letter 'C' in 22.29% of the cases, and 11.82% had the typical shape of the letter 'C,' and in 10.47% of the patients it paralleled the inverted letter 'C' (upside down). Amongst the types of the MS shifting directions the rarest was the MS that resembled the letter 'S' - 11.48% of the patients. In 5.74% of the cases it looked like the typical letter 'S,' and in 5.74% of the cases it was similar to the inverted letter 'S.' Only 16.22% of the cases had the MS that did not change its course nor its shape and ran medially in the sagittal plane from the anterior to the posterior part of the sinuses. Conclusions: In furtherance of reducing the risk of problems occurring during a surgery in the paranasal sinuses, it is prudent to have a CT scan done in all the patients beforehand, due to the high prevalence of the anatomical variations in the sinuses.

CRACoV-HHS: an interdisciplinary project for multi-specialist hospital and non-hospital care for patients with SARS-CoV-2 infection as well hospital staff assessment for infection exposure.

The complex course of the COVID-19 and the distant complications of the SARS-CoV-2 infection still remain an unfaded challenge for modern medicine. The care of patients with the symptomatic course of COVID-19 exceeds the competence of a single specialty, often requiring a multispecialist approach. The CRACoV-HHS (CRAcow in CoVid pandemic - Home, Hospital and Staff) project has been developed by a team of scientists and clinicians with the aim of optimizing medical care at hospital and ambulatory settings and treatment of patients with SARS-CoV-2 infection. The CRACoV project integrates 26 basic and clinical research from multiple medical disciplines, involving different populations infected with SARS-CoV-2 virus and exposed to infection. Between January 2021 and April 2022 we plan to recruit subjects among patients diagnosed and treated in the University Hospital in Cracow, the largest public hospital in Poland, i.e. 1) patients admitted to the hospital due to COVID-19 [main module: 'Hospital']; 2) patients with signs of infection who have been confirmed as having SARS-CoV-2 infection and have been referred to home isolation due to their mild course (module: 'Home isolation'); 3) patients with symptoms of infection and high exposure to SARS- CoV-2 who have a negative RT-PCR test result. In addition, survey in various professional groups of hospital employees, both medical and non-medical, and final-fifth year medical students (module: 'Staff') is planned. The project carries both scientific and practical dimension and is expected to develop a multidisciplinary model of care of COVID-19 patients as well as recommendations for the management of particular groups of patients including: asymptomatic patient or with mild symptoms of COVID-19; symptomatic patients requiring hospitalization due to more severe clinical course of disease and organ complications; patient requiring surgery; patient with diabetes; patient requiring psychological support; patient with undesirable consequences of pharmacological treatment.

Effect of Thermal Insulation on Image Quality and Radiation Dose in Polytrauma Computed Tomography.

PURPOSE: Unintentional drop in body temperature in trauma victims is an independent risk factor for mortality. We aimed to assess the impact of thermal insulation on image quality and radiation dose in polytrauma computed tomography (CT). METHODS: Thirteen different insulating covers were used to wrap CT phantoms. Images were assessed subjectively at a radiological workstation and analyzed digitally with dedicated software evaluating the noise intensity, spatial resolution, and image homogeneity. The radiation dose was measured using a dosimeter. RESULTS: Most materials did not cause significant artifacts apart from 2 heating pads. Although the radiation dose was increased by the majority of insulating covers (up to 64.66%), certain covers decreased the absorbed radiation (up to -7.35%). CONCLUSIONS: The majority of insulating systems do not cause artifacts in CT scans. When using covers with self-heating warmers, removing the heating pad is suggested due to the risk of considerable artifacts appearing. Certain insulating covers may increase or decrease the radiation dose.

The height and type of the main septum in the sphenoid sinuses - evaluation before the fess.

The purpose of this study was to examine the height of the main septum (MS) in the sphenoid sinuses and its type, depending on the percentage prevalence of its tissue composition (osseous and membranous) in the adult population. Materials and Methods: A retrospective analysis of 296 computed tomography (CT) scans (147 females, 149 males) of the paranasal sinuses was conducted. The patients did not present any pathology in the sphenoid sinuses. The CT scans of the paranasal sinuses were carried out with a spiral CT scanner (Siemens Somatom Sensation 16) in a standard procedure, in the option Siemens CARE Dose 4D. No contrast medium was used. Having obtained the transversal planes, a secondary reconstruction tool (multiplans reconstruction - MPR) was used in furtherance of gleaning sagittal and frontal planes. R e s u l t s: In all cases, the height of the MS was measured by using a straight line running parallel to the course of the septum (when the MS was regarded as straight) or curved (when the MS was regarded as irregularly shaped). The average height of the MS was 2.1 ± 0.41 cm in the whole research group. Completely osseous MS was found in 32.77% of the patients. In 63.85% of them, the MS was partially membranous. The rarest was the MS which was not even partially ossified - a membranous type, that was observed in 3.38% of the patients. C o n c l u s i o n s: Variant anatomy of the paranasal sinuses may lead to complications encountered during a surgery, hence a CT scan is advised before the planned treatment.

Incorporation of the sphenoid sinuses' septum / septa in the carotid canal - evaluation before the FESS.

The purpose of the research was to define the frequency prevalence of the incorporation of sphenoid sinuses' septum / septa in the carotid canal of the adult population. MATERIALS AND METHODS: 296 computed tomography (CT) scans of the patients (147 females, 149 males), who did not present any pathology in the sphenoid sinuses, were evaluated in this retrospective analysis. Spiral CT scanner - Siemens Somatom Sensation 16 - was used to glean the medical images. Standard procedure applied in the option Siemens CARE Dose 4D. No contrast medium was administered. Multiplans reconstruction (MPR) tool was used in order to obtain frontal and sagittal planes from the transverse planes previously received. RESULTS: Bilateral incorporation of the main septum (MS) in the carotid canal was not present in any of the patients, whereas unilateral incorporation was noticed in 21.96% of the patients (17.68% females, 26.17% males). On the right side it occurred in 11.82% of cases (10.88% females, 12.75% males), and on the left side in 10.14% of cases (6.8% females, 13.42% males). Bilateral incorporation of the additional septum (AS) was found in 8.45% of the patients (4.08% females, 12.75% males), whereas unilateral incorporation was noted in 28.37% of the patients. It was seen on the right side in 11.82% of cases (12.93% females, 10.74% males), and on the left side in 16.55% cases (15.65% females, 17.45% males). The most common variant was the incorporation of only one of the septa (either the MS or the AS) in the wall of the carotid canal unilaterally. Such situation took place in 30.07% of the patients (29.25% females, 30.87% males). Incorporation of two septa on the same side was noticed in 4.39% of cases (4.08% females, 4.7% males), and incorporation of three septa in 0.34% of cases (0.7% males). CONCLUSIONS: The anatomy of the paranasal sinuses is varied to a great extent, hence performing a CT scan is crucial before the scheduled surgery, as it may lessen the unforeseeable surgical complications, that may result from the high prevalence of variants in the sinuses.

Prognostic and predictive implications of sarcopenia in Western patients undergoing gastric resections for carcinoma of the stomach.

INTRODUCTION: Sarcopenia is highly prevalent in patients with gastrointestinal malignancies, including gastric cancer, but there is a lack of adequate data from Western populations. METHODS: Computed tomography scans of 138 Caucasian patients subject to stomach resections due to gastric adenocarcinoma between 2012 and 2015 were reviewed to evaluate the impact of sarcopenia. The definition of sarcopenia was based on the lumbar skeletal muscle index (SMI) using cut-off values formulated by the international consensus definitions of sarcopenia (SMI <52.4 cm2 /m2 for men and <38.5 cm2 /m2 for women). RESULTS: Sixty (43%) of 138 patients were sarcopenic. Sarcopenia was associated with postoperative morbidity (43% vs 23%; P = .011), major postoperative complications (Clavien-Dindo ≥3a; 36% vs 21%; P = .035), and reoperations (23% vs 9%; P = .020). Patients with sarcopenia also had prolonged postoperative hospital stay (8.0 vs 6.5 days; P = .010). The overall median survival of patients with sarcopenia was significantly lower than those with normal skeletal muscles (11.0 vs 36.7 months; P = .005) and sarcopenia remained an independent prognostic factor with an odds ratio of 1.94 (95% confidence interval, 1.08 to 3.48; P = .026). CONCLUSION: Sarcopenia, defined by SMI, is associated with an increased risk of postoperative morbidity and impaired long-term survival.

The effect of software post-processing applications on identification of the penumbra and core within the ischaemic region in perfusion computed tomography.

PURPOSE: Assessment of software applications designed for post-processing of CT imaging data and perfusion maps in terms of their ability to consistently define the penumbra and core in an ischemic area. MATERIAL AND METHODS: This study is based on measurements conducted in a group of 65 patients with neurological symptoms suggestive of ischaemia in the area of the MCA within 12 hours following onset of the first symptoms. Non-contrast and perfusion CT were performed during an emergency duty. The acquired data were processed using various programs to obtain defined ischaemic areas and parameters. Finally, the results obtained were compared to the distribution of penumbra and core within the ischaemic area received from different perfusion mapping programs. RESULTS: The programs designed to convert the acquired data and to map the distribution of perfusion were also assessed for their viability in dividing the ischaemic zone into penumbra and core. There was a statistically strong correlation (0.784-0.846) between results obtained by processing of imaging data with two different packages, and then by post-processing with one package, and a poor correlation (0.315-0.554) between results obtained by processing of data with the same package, and post-processing with two different packages designed for measuring penumbra and core areas. CONCLUSIONS: The results obtained by processing of imaging data with different software applications and by post-processing with one program developed for identifying penumbra and core areas show a strong correlation. However, the results obtained by processing imaging data with the same software application and by post-processing with different programs measuring penumbra and core areas reveal poor correlation.

The total number of septa and antra in the sphenoid sinuses - evaluation before the FESS.

PURPOSE: The purpose of this research is to define the total number of septa and the total number of antra in the sphenoid sinuses (created as a result of the presence of additional septa), as well as the relation between the number of the septa and their location in the adult population. MATERIALS AND METHODS: e study was conducted as a retrospective analysis of the computed tomography (CT) scans of the paranasal sinuses of 296 patients (147 females and 149 males), who did not present any pathology in the sphenoid sinuses. The CT scans of the paranasal sinuses were done with the spiral CT scanner (Siemens Somatom Sensation 16) by using a standard procedure, in the option Siemens CARE Dose 4D, without using any contrast medium. A er obtaining the transverse planes, the frontal and sagittal planes were created using secondary reconstruction tool (multiplans reconstruction - MPR). RESULTS: The analysis of the obtained images in the transverse plane and secondary CT reconstructions has shown the presence of only one sphenoid septum (main septum - MS) in 21.96% of the patients, which divided the sphenoid sinus into two sphenoid antra. In 78.04% of the patients, there were more than one sphenoid septa present in the posterior part of the sphenoid sinuses, hence there were additional septa (AS) present. One AS was present in 22.97% of the patients. The most common variant - two AS - was found in 32.09% of the cases. The presence of more than two AS was found in the following number of patients: three AS in 9.8%, four AS in 7.09%, five AS in 1.69%, six AS in 3.04% and seven AS in 1.01%. The rarest variant was the presence of more than seven AS: eight AS in 0.34% and nine AS also in 0.34%. There were no sphenoid sinuses that would have more than nine AS in the researched material. CONCLUSIONS: Due to the high incidence of the anatomical variants of the paranasal sinuses, a CT scan is recommended in all patients before a planned surgery in order to avoid the potential complications that might arise as a result of the complicated structure of the paranasal sinuses.

The assessment of diagnostic medical images using 10-bit grayscale - fact or myth?

PURPOSE: The aim of the study was to find tests for verification of 10-bit grayscale support for radiological workstation hardware/operating system and for DICOM viewer. Also, we wanted to perform the tests on available workstations. MATERIAL AND METHODS: The following tests were selected to verify 10-bit grayscale support: workstation hardware and operating system tests using DirectX SDK 10BitScanout10.exe and NEC 10bitdemo.exe programs, DICOM viewer tests using TG18-MP and TG18-QC patterns. The tests were performed on 14 radiological workstations in a local department of radiology and on 4 radiological workstations during the technical exhibition at the ECR (European Congress of Radiology) in 2017. RESULTS: Only 3 out of 14 local workstations passed the hardware and operating system 10-bit grayscale support test. Only one workstation passed the DICOM viewer 10-bit grayscale support test. CONCLUSIONS: Hardware/operating system and DICOM viewer 10-bit grayscale support should be tested on every radiological workstation even if compatibility is stated by the manufacturer. Existing medical diagnostic display quality requirements should be adjusted so that 10-bit support for DICOM viewers is only a desirable option.

In vitro analysis of urinary stone composition in dual-energy computed tomography.

PURPOSE: Dual energy computed tomography (DECT) is a new method of computed tomography (CT) imaging, allowing the assessment of not only the object's morphology, but also its composition. The aim of the study was to evaluate the potential of in vitro DECT evaluation of urinary stones' chemical composition. MATERIAL AND METHODS: Six samples of surgically removed renal stones were scanned using DECT and analyzed by scanner vendor software. Uric acid stones were marked red and calcium stones white by the software. The real composition of the stones was finally verified using physicochemical laboratory analysis. RESULTS: In 5 out of 6 samples, the composition of stones in DECT (3 samples identified as uric acid and 2 samples as calcium) was consistent with the physicochemical analysis (3 samples identified as uric acid, 1 as calcium phosphate, 1 as calcium oxalate). In DECT it was not possible to determine more precisely the type of calcium compounds (calcium phosphate vs. calcium oxalate) as established in the physicochemical analysis.In one stone identified in physicochemical analysis as uric acid, DECT detected a composite layered structure containing both uric acid and calcium compounds. CONCLUSIONS: DECT allows uric acid to be distinguished from calcium urinary tract stones, which is crucial in the choice of appropriate therapy. Using the available hardware and software, it was not possible to more accurately distinguish types of calcified stones. Evaluation of the stone type in DECT may be limited in the case of mixed chemical composition.

How to avoid false positive hyperdense middle cerebral artery sign detection in ischemic stroke.

OBJECTIVES: The aim of the study was to find how to differentiate hyperdense middle cerebral artery sign (HMCAS) in stroke patients from asymmetric hyperdensity not related to stroke, by comparison of the CT density values typical for HMCAS to the values in normal or atherosclerotic middle cerebral artery (MCA). METHODS: The group analyzed consisted of 100 patients with ischemic stroke, presenting HMCAS on the admission CT. Density measurements in HU were performed in the hyperdense segment of the involved MCA, contralateral MCA, brain cortex adjacent to the hyperdense MCA. The control group consisted of 100 patients with no symptoms of cerebral stroke. Density measurements in HU were performed: in the M1 segment of right and left MCA, brain cortex adjacent to the more dense from right or left MCA. RESULTS: In the stroke group the median values obtained were: in the hyperdense MCA 59 HU, contralateral MCA 41 HU, brain cortex 36 HU. In the control group the median values obtained were: in the more dense MCA 43 HU, contralateral MCA 40 HU, brain cortex 34 HU. The range of HMCAS/contralateral MCA density ratios in stroke only slightly overlapped the range of more dense MCA/contralateral MCA density ratios in non-stroke patients. CONCLUSION: The ratio of hyperdense MCA CT density/contralateral density is a good tool to differentiate HMCAS from asymmetric hyperdensity not related to stroke. The threshold ≥1.16 provided 100% sensitivity and 97% specificity, whereas ≥1.22 provided 94% sensitivity and 100% specificity.

Hyperdense middle cerebral artery sign as the only radiological manifestation of hyperacute ischemic stroke in computed tomography.

OBJECTIVES: The main aim of the study was to find the effect of hyperdense middle cerebral artery sign (HMCAS), as the only admission computed tomography (CT) manifestation of ischemic stroke involving middle cerebral artery (MCA) region, on the extent of stroke measured by Alberta Stroke Program Early CT score (ASPECTS) in the follow-up CT. The secondary aim was to determine the correlation between length of hyperdense MCA segment on admission CT and ASPECTS in follow-up CT. METHODS: The group analyzed consisted of 118 patients with ischemic MCA region stroke, with no early signs of brain tissue ischemia on admission CT, but infarcts confirmed in follow-up CT, with extent evaluated using ASPECTS. For the subgroups: 66 patients with HMCAS present and 52 with HMCAS absent, median ASPECTS values were compared. In the subgroup with HMCAS present, length of hyperdense segment was measured and correlation with ASPECTS was determined. RESULTS: The median ASPECTS 6 (min. 0, max. 9) in the subgroup with HMCAS present was significantly lower, compared to the score 8.5 (min. 0, max. 9) in the subgroup with HMCAS absent. Moderate correlation between the length of hyperdense segment and ASPECTS was found (R=-0.45). CONCLUSION: In patients with ischemic stroke involving MCA region and no early signs of brain tissue ischemia on the admission CT, HMCAS is associated with significantly lower ASPECTS in the follow-up CT. There is moderate correlation between the length of hyperdense MCA segment and ASPECTS.

Whole-Body Low-Dose Computed Tomography (WBLDCT) in Assessment of Patients with Multiple Myeloma - Pilot Study and Standard Imaging Protocol Suggestion.

BACKGROUND: For decades, the main imaging tool in multiple myeloma (MM) patients was plain radiography. However, computed tomography (CT) has been included in the updated criteria of MM. The main disadvantage of CT is a considerably high radiation dose. Therefore, low-dose CT protocols could be a solution. The aim of the study was to (1) preliminarily analyse the usefulness of Whole-Body Low-Dose CT (WBLDCT) in the evaluation of patients with MM and (2) to make adjustments in the standard CT imaging protocol. MATERIAL/METHODS: In 41 patients with MM, WBLDCT was performed. The following parameters were used: detector configuration - 80×0.5 mm, scanning range in a single spiral acquisition from the skull to the proximal femoral bones, tube voltage - 120 kVp, current tube time product - 86 mAs, slice thickness 1 mm. Two sets of axial images were reconstructed for bone and soft tissue assessment, respectively. Secondary coronal and sagittal reconstructions were generated. Typical MM features were analysed and qualitatively compared with radiography results. RESULTS: A potentially increased sensitivity of CT, as compared to radiography, in detecting lytic foci obscured by other structures or with a small degree of destruction was seen. A potentially increased specificity of CT was found in detecting cases of small foci suspicious of lytic lesions on skull radiographs, seen as arachnoid granulations fovea in CT. The following radiation parameters were recorded: max. CTDIvol - 7.4 mGy and DLP - 660-810 mGy×cm. WBLDCT was much shorter and more convenient to patients. CONCLUSIONS: WBLDCT may become a valuable part of the assessment of MM features at a much lower radiation dose compared to standard CT protocols. It has a potential ability to increase diagnostic accuracy compared to radiography.