Prediction of IDH Mutation Status in High-grade Gliomas Using DWI and High T1-weight DSC-MRI.

RATIONALE AND OBJECTIVES: We aimed to evaluate the diagnostic performance of diffusion-weighted imaging (DWI) and dynamic susceptibility contrast-enhanced (DSC) magnetic resonance imaging (MRI) parameters in the noninvasive prediction of the isocitrate dehydrogenase (IDH) mutation status in high-grade gliomas (HGGs). MATERIALS AND METHODS: A total of 58 patients with histopathologically proved HGGs were included in this retrospective study. All patients underwent multiparametric MRI on 3-T, including DSC-MRI and DWI before surgery. The mean apparent diffusion coefficient (ADC), relative maximum cerebral blood volume (rCBV), and percentage signal recovery (PSR) of the tumor core were measured and compared depending on the IDH mutation status and tumor grade. The Mann-Whitney U test was used to detect statistically significant differences in parameters between IDH-mutant-type (IDH-m-type) and IDH-wild-type (IDH-w-type) HGGs. Receiver operating characteristic curve (ROC) analysis was performed to evaluate the diagnostic performance. RESULTS: The rCBV was significantly higher, and the PSR value was significantly lower in IDH-w-type tumors than in the IDH-m group (p = 0.002 and <0.001, respectively).The ADC value in IDH-w-type tumors was significantly lower compared with the one in IDH-m types (p = 0.023), but remarkable overlaps were found between the groups. The PSR showed the best diagnostic performance with an AUC of 0.938 and with an accuracy rate of 0.87 at the optimal cutoff value of 86.85. The combination of the PSR and the rCBV for the identification of the IDH mutation status increased the discrimination ability at the AUC level of 0.955. In terms of each tumor grade, the PSR and rCBV showed significant differences between the IDH-m and IDH-w groups (p ≤0.001). CONCLUSION: The rCBV and PSR from DSC-MRI may be feasible noninvasive imaging parameters for predicting the IDH mutation status in HGGs. The standardization of the imaging protocol is indispensable to the utility of DSC perfusion MRI in wider clinical usage.

Relationship between chest computed tomography findings and clinical conditions of coronavirus disease (COVID-19): A multicentre experience.

AIMS: This study aimed to investigate the clinical and chest computed tomography (CT) features associated with clinical parameters for coronavirus disease (COVID-19) in the capital of Turkey, Ankara. MATERIALS AND METHODS: Epidemiological, clinical features, laboratory findings and radiological characteristics of 1563 hospitalised patients with COVID-19 in Ankara were collected, reviewed and analysed in this study. The risk factors associated with disease severity were investigated. RESULTS: Non-severe (1214; 77.7%) and severe cases (349; 22.3%) were enrolled in the study. Compared with the non-severe group, the severe group were significantly older and had more comorbidities (ie, hypertension, diabetes mellitus, cardiovascular disease and chronic kidney disease). Smoking was more common in the severe group. Severe patients had higher respiratory rates and higher incidences of cough and dyspnoea compared with non-severe patients. Compared with the non-severe patients, the severe patients had increased C-reactive protein (CRP), procalcitonin, neutrophil to lymphocyte ratio (NLR) and CRP/albumin ratio and decreased albumin. The occurrence rates of consolidation, subpleural sparing, crazy-paving pattern, cavity, halo sign, reversed halo sign, air bronchogram, pleural thickening, micronodule, subpleural curvilinear line and multilobar and bilateral involvement in the CT finding of the severe patients were significantly higher than those of the non-severe patients. CONCLUSIONS: Many factors are related to the severity of COVID-19, which can help clinicians judge the severity of the patient and evaluate the prognosis. This cohort study revealed that male sex, age (≥55 years), patients with any comorbidities, especially those with cardiovascular disease, dyspnoea, increased CRP, D-dimer and NLR, and decreased lymphocyte count and CT findings of consolidation and multilobar involvement were predictors of severe COVID-19.

Accuracy in tumor size measurements: Comparison of digital mammography, digital breast tomosynthesis and synthetic mammography.

PURPOSE: The aim of this study was to assess the accuracy of digital mammography (DM), digital breast tomosynthesis (DBT) and synthetic mammography (SM) in tumor size measurements compared with histological tumor sizes. MATERIALS AND METHODS: 71 breast cancer patients who underwent DM and DBT acquisitions simultaneously were included in this study. One radiologist with 8 years of experience in breast imaging measured tumor sizes independently in three separate sessions which include DM, DBT and SM images, respectively. The correlations between the measured tumor sizes on each imaging technique and histological sizes were analyzed using Spearman correlation test. The patients were categorized into two subgroups according to assigned breast density categories (dense and non-dense), and histological tumor sizes (≤2 cm and > 2 cm). To assess the agreement levels between the measured tumor sizes and histological sizes Bland-Altman analyses were performed for each imaging technique. RESULTS: The mean of histological size of tumors was 23.85 ±â€¯16.57 mm (median: 20). The means of measured tumor sizes were 21.21 ±â€¯13.59 mm (median: 19), 21.52 ±â€¯13.42 mm (median: 19) and 18.97 ±â€¯11.21 mm (median: 17) in DM, DBT and SM, respectively. The Spearman correlation values with histologic sizes were 0.814 (P < 0.001), 0.887 (P < 0.001), and 0.852 (P < 0.001) for DM, DBT and SM, respectively. In subgroup analyses, the correlation values showed decrement for tumors >2 cm in size compared to tumors ≤2 cm in size. CONCLUSION: DBT provides the most accurate tumor size measurements among mammographic imaging techniques and if mammography will be used in tumor size measurements, DBT should be preferred.

Validation of combined use of DWI and percentage signal recovery-optimized protocol of DSC-MRI in differentiation of high-grade glioma, metastasis, and lymphoma.

PURPOSE: With conventional MRI, it is often difficult to effectively differentiate between contrast-enhancing brain tumors, including primary central nervous system lymphoma (PCNSL), high-grade glioma (HGG), and metastasis. This study aimed to assess the discrimination ability of the parameters obtained from DWI and the percentage signal recovery- (PSR-) optimized protocol of DSC-MRI between these three tumor types at an initial step. METHODS: DSC-MRI using a PSR-optimized protocol (TR/TE = 1500/30 ms, flip angle = 90°, no preload) and DWI of 99 solitary enhancing tumors (60 HGGs, 24 metastases, 15 PCNSLs) were retrospectively assessed before treatment. rCBV, PSR, ADC in the tumor core and rCBV, and ADC in peritumoral edema were measured. The differences were evaluated using one-way ANOVA, and the diagnostic performance was evaluated using ROC curve analysis. RESULTS: PSR in the tumor core showed the best discriminating performance in differentiating these three tumor types with AUC values of 0.979 for PCNSL vs. others and 0.947 for HGG vs. metastasis. The ADC was only helpful in the tumor core and distinguishing PCNSLs from others (AUC = 0.897). CONCLUSION: Different from CBV-optimized protocols (preload, intermediate FA), PSR derived from the PSR-optimized protocol seems to be the most important parameter in the differentiation of HGGs, metastases, and PCNSLs at initial diagnosis. This property makes PSR remarkable and carries the need for comprehensive DSC-MRI protocols, which provides PSR sensitivity and CBV accuracy together, such as the preload use of the PSR-optimized protocol before the CBV-optimized protocol.

The utility of shear wave elastography in the evaluation of muscle stiffness in patients with cerebral palsy after botulinum toxin A injection.

PURPOSE: The first aim of this study was to evaluate changes in the stiffness of the medial gastrocnemius muscle (GM) after a botulinum toxin A (BoNT-A) injection in children with cerebral palsy (CP) using shear wave elastography (SWE). We also wanted to investigate the usability of SWE for evaluating spasticity in a clinical setting. The second aim of this study was to show how treatment of the gastrocnemius muscle spasticity caused a change in the elasticity of the anterior tibial (TA) muscle. METHODS: Twenty-four pediatric patients diagnosed with a spastic type of CP, who were scheduled to receive a BoNT-A injection in the gastrocnemius muscle, were included in the study. There was a total of 43 lower extremities to evaluate, and muscle stiffness was measured before the injection and a month post injection using SWE. The physiatrist evaluated muscle spasticity using the Modified Ashworth Scale (MAS) and the Modified Tardieu Scale at about the same time. RESULTS: SWE values of the GM (pre-BoNT-A: 45.9 ± 6.5 kPa, post-BoNT-A: 25.0 ± 5.7 kPa) decreased significantly post BoNT-A injection (P < 0.01). SWE measurements of the GM had positive correlations with MAS, V1X, V3X, and R2-R1 (P < 0.01); and negative correlations with R2 and R1 (P < 0.05). SWE values of the TA muscle (pre: 36.9 ± 7.9 kPa, post: 28.4 ± 5.2 kPa) decreased significantly (P < 0.01). CONCLUSION: Quantitative measurement of muscle stiffness using SWE may provide important information for the evaluation of spasticity and treatment efficiency in pediatric CP patients.

Comparison of Mass Size Measurements: Synthesized Mammography Versus Full-Field Digital Mammography.

OBJECTIVES: To compare mass size measurements between synthesized mammography (SM) and full-field digital mammography (FFDM), and to assess interobserver agreement for those measurements. MATERIALS AND METHODS: One hundred and forty-three patients who underwent FFDM and digital breast tomosynthesis acquisitions during the same compression session were included in the study. Two observers with four-and 1-year experience with digital breast tomosynthesis and SM images, respectively, measured mass sizes independently in two different sessions that were 2 weeks apart, and were blinded to each other. The first session included only FFDM images, and the second session included only SM images. Largest dimension of masses was measured in millimeters. Paired t test was used to compare differences in size measurements between FFDM and SM images. Intraclass correlation coefficient test was used to analyze interobserver agreement. Bland-Altman analyses were performed to evaluate agreements between the imaging techniques and between the observers. RESULTS: The mean mass sizes on FFDM and SM images were 20.27 ± 14.10 and 18.50 ± 13.05 mm, respectively, for the first observer and 21.56 ± 14.84 and 19.89 ± 13.68 mm, respectively, for the second observer. The mass size measurements were significantly different between FFDM and SM for both observers (p < 0.001). Range of measurement errors, defined as 95% limits of agreements between two imaging techniques for observers 1 and 2 were ±1.96*1.36 mm, and ±1.96*1.53 mm, respectively. Range of measurement errors, defined as 95% limits of agreements between two observers for SM and FFDM were ±1.96*3.68 mm, and ±1.96*3.35 mm, respectively. CONCLUSION: The measured mass sizes were significantly smaller on SM than FFDM images, and the interobserver differences for both of the imaging techniques were greater than the differences measured between FFDM and SM images.

The Utility of Diffusion-Weighted Imaging and Perfusion Magnetic Resonance Imaging Parameters for Detecting Clinically Significant Prostate Cancer.

INTRODUCTION: To establish the diagnostic performance of the parameters obtained from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging at 3T in discriminating between non-clinically significant prostate cancers (ncsPCa, Gleason score [GS] < 7) and clinically significant prostate cancers (csPCa, GS ≥ 7) in the peripheral zone. MATERIALS AND METHODS: Twenty-six male patients with peripheral zone prostate cancer (PCa) who had undergone 3T multiparametric magnetic resonance imaging (MRI) scan prior to biopsy were included in the study and evaluated retrospectively. The GS was obtained by both standard 12-core transrectal ultrasound guided biopsy and targeted MRI-US fusion biopsy and then confirmed by prostatectomy, if available. For each confirmed tumour focus, DCE-derived quantitative perfusion metrics (Ktrans, Kep, Ve, initial area under the curve [AUC]), the apparent diffusion coefficient (ADC) value, and normalized versions of quantitative metrics were measured and correlated with the GS. RESULTS: Ktrans had the highest diagnostic accuracy value of 82% among the DCE-MRI parameters (AUC 0.90), and ADC had the strongest diagnostic accuracy value of 87% among the overall parameters (AUC 0.92). The combination of ADC and Ktrans have higher diagnostic performance with the area under the receiver operating characteristic curve being 0.98 (sensitivity 0.94; specificity 0.89; accuracy 0.92) compared to the individual evaluation of each parameter alone.The GS showed strong negative correlations with ADC (r = -0.72) and normalized ADC (r = -0.69) as well as a significant positive correlation with Ktrans (r = 0.69). CONCLUSION: The combination of Ktrans and ADC and their normalized versions may help differentiate between ncsPCa from csPCa in the peripheral zone.