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1.
Neuroradiology ; 66(4): 521-530, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38347151

RESUMO

PURPOSE: T2-FLAIR mismatch serves as a highly specific but insensitive marker for IDH-mutant (IDHm) astrocytoma with potential limitations in real-world application. We aimed to assess the utility of a broader definition of T2-FLAIR discordance across a cohort of adult-type diffuse lower-grade gliomas (LrGG) to see if specific patterns emerge and additionally examine factors determining deviation from the classic T2-FLAIR mismatch sign. METHODS: Preoperative MRIs of non-enhancing adult-type diffuse LrGGs were reviewed. Relevant demographic, molecular, and MRI data were compared across tumor subgroups. RESULTS: Eighty cases satisfied the inclusion criteria. Highest discordance prevalence and > 50% T2-FLAIR discordance volume were noted with IDHm astrocytomas (P < 0.001), while < 25% discordance volume was associated with oligodendrogliomas (P = 0.03) and IDH-wildtype (IDHw) LrGG (P = 0.004). "T2-FLAIR matched pattern" was associated with IDHw LrGG (P < 0.001) and small or minimal areas of discordance with oligodendrogliomas (P = 0.03). Sensitivity and specificity of classic mismatch sign for IDHm astrocytoma were 25.7% and 100%, respectively (P = 0.06). Retained ATRX expression and/or non-canonical IDH mutation (n = 10) emerged as a significant factor associated with absence of classic T2-FLAIR mismatch sign in IDHm astrocytomas (100%, P = 0.02) and instead had minimal discordance or matched pattern (40%, P = 0.04). CONCLUSION: T2-FLAIR discordance patterns in adult-type diffuse LrGGs exist on a diverging but distinct spectrum of classic mismatch to T2-FLAIR matched patterns. Specific molecular markers may play a role in deviations from classic mismatch sign.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioma , Oligodendroglioma , Adulto , Humanos , Neoplasias Encefálicas/patologia , Estudos Retrospectivos , Isocitrato Desidrogenase/genética , Glioma/patologia , Imageamento por Ressonância Magnética , Astrocitoma/genética , Mutação
2.
Neuroradiology ; 66(6): 947-953, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38625616

RESUMO

PURPOSE: Basal duct-like recess (DR) sign serves as a specific marker of papillary craniopharyngiomas (PCPs) of the strictly third-ventricular (3 V) topography. Origins of this sign are poorly understood with limited validation in external cohorts. METHODS: In this retrospective study, MRIs of pathologically proven PCPs were reviewed and evaluated for tumor topography, DR sign prevalence, and morphological subtypes. RESULTS: Twenty-three cases with 24 MRIs satisfied our inclusion criteria. Median age was 44.5 years with a predominant male distribution (M/F ratio 4.7:1). Overall, strictly 3 V was the commonest tumor topography (8/24, 33.3%), and tumors were most commonly solid-cystic (10/24, 41.7%). The prevalence of DR sign was 21.7% (5/23 cases), all with strictly 3 V topography and with a predominantly solid consistency. The sensitivity, specificity and positive and negative predictive value of the DR sign for strict 3 V topography was 62.5%, 100%, 100% and 84.2% respectively. New pertinent findings associated with the DR sign were observed in our cohort. This included development of the cleft-like variant of DR sign after a 9-year follow-up initially absent at baseline imaging. Additionally, cystic dilatation of the basal tumor cleft at the pituitary stalk-tumor junction and presence of a vascular structure overlapping the DR sign were noted. Relevant mechanisms, hypotheses, and implications were explored. CONCLUSION: We confirm the DR sign as a highly specific marker of the strictly 3 V topography in PCPs. While embryological and molecular factors remain pertinent in understanding origins of the DR sign, non-embryological mechanisms may play a role in development of the cleft-like variant.


Assuntos
Craniofaringioma , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias , Sensibilidade e Especificidade , Humanos , Masculino , Craniofaringioma/diagnóstico por imagem , Feminino , Neoplasias Hipofisárias/diagnóstico por imagem , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Idoso , Prevalência , Adolescente , Terceiro Ventrículo/diagnóstico por imagem , Terceiro Ventrículo/patologia
3.
Can Assoc Radiol J ; : 8465371231221052, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38189316

RESUMO

BACKGROUND: Multi-detector contrast-enhanced abdominal computed tomography (CT) allows for the accurate detection and classification of traumatic splenic injuries, leading to improved patient management. Their effective use requires rapid study interpretation, which can be a challenge on busy emergency radiology services. A machine learning system has the potential to automate the process, potentially leading to a faster clinical response. This study aimed to create such a system. METHOD: Using the American Association for the Surgery of Trauma (AAST), spleen injuries were classified into 3 classes: normal, low-grade (AAST grade I-III) injuries, and high-grade (AAST grade IV and V) injuries. Employing a 2-stage machine learning strategy, spleens were initially segmented from input CT images and subsequently underwent classification via a 3D dense convolutional neural network (DenseNet). RESULTS: This single-centre retrospective study involved trauma protocol CT scans performed between January 1, 2005, and July 31, 2021, totaling 608 scans with splenic injuries and 608 without. Five board-certified fellowship-trained abdominal radiologists utilizing the AAST injury scoring scale established ground truth labels. The model achieved AUC values of 0.84, 0.69, and 0.90 for normal, low-grade injuries, and high-grade splenic injuries, respectively. CONCLUSIONS: Our findings demonstrate the feasibility of automating spleen injury detection using our method with potential applications in improving patient care through radiologist worklist prioritization and injury stratification. Future endeavours should concentrate on further enhancing and optimizing our approach and testing its use in a real-world clinical environment.

4.
AJR Am J Roentgenol ; 216(2): 355-361, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32755161

RESUMO

OBJECTIVE. Cardiac involvement is the leading cause of mortality in Fabry disease. Noninvasive markers of cardiac involvement are needed to identify patients at high risk. The purpose of this study was to evaluate the diagnostic potential of segmental native T1 spread as an imaging biomarker in Fabry disease. SUBJECTS AND METHODS. In this prospective study, 43 patients with confirmed Fabry disease (mean ± SD age, 46±14 years; 70% women) and 17 healthy control subjects (mean ± SD age, 44 ±13 years; 53% women) underwent 3-T cardiac MRI including modified Look-Locker inversion recovery T1 mapping. Segmental native T1 spread was calculated as the difference between maximum and minimum segmental native T1 values, expressed as an absolute value and as a relative percentage of global native T1. RESULTS. Absolute and relative segmental native T1 spreads were significantly higher in patients with Fabry disease than in healthy control subjects (absolute median, 115 vs 98 ms [p = 0.004]; relative median, 9.9% vs 8.0% [p < 0.001]) and correlated positively with quantitative late gadolinium enhancement (absolute, r = 0.434, p < 0.001; relative, r = 0.436, p < 0.001), indexed left ventricular mass (absolute, r = 0.316, p = 0.01; relative, r = 0.347, p = 0.007), and global longitudinal strain (absolute, r = 0.289, p = 0.03; relative, r = 0.277, p = 0.03). Relative segmental native T1 spread differentiated patients with Fabry disease from healthy control subjects (odds ratio, 1.44 [95% CI, 1.10-1.89]; p = 0.009). Interob-server agreement was excellent for both absolute (intraclass correlation coefficient, 0.932) and relative (intraclass correlation coefficient, 0.926) segmental native T1 spread. CONCLUSION. Increased native T1 spread is a reproducible imaging biomarker of cardiac involvement in Fabry disease and may be particularly useful in the evaluation of patients who cannot undergo late gadolinium enhancement imaging.


Assuntos
Doença de Fabry/complicações , Doença de Fabry/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Cardiopatias/etiologia , Imageamento por Ressonância Magnética , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Razão de Chances , Estudos Prospectivos , Reprodutibilidade dos Testes
5.
Childs Nerv Syst ; 37(1): 217-223, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32803307

RESUMO

OBJECTIVE: To compare the utility of constructive interference in steady-state (CISS) sequence over T2-weighted (T2W) sequence in the accurate delineation of the tethering element on magnetic resonance (MR) imaging in patients of tethered cord syndrome (TCS) and correlation with intraoperative findings. METHODS: MR findings of fifty-six consecutive patients with operative findings of TCS were studied. The intraoperative findings of all patients were studied and compared with the preoperative imaging findings on T2W imaging and CISS images. RESULTS: CISS images provided more information than T2W imaging. The overall sensitivity of CISS in MR evaluation of patients with TCS was higher (99.17%) as compared with the T2W sequence (71.48%) especially in the detection of precise position/extent of tethered cord, assessment of filum terminale thickening, detection of a fibrous spur in cases of split cord malformation, detection of dorsal dermal sinus, and evaluation of its precise extent and ramifications. The area under the ROC curve was higher with CISS (0.99) than with T2W sequence (0.85) which reflects its good predictive value as a screening test. This information was useful to the operating surgeon. CONCLUSION: CISS sequence for imaging TCS can help enhance the overall surgical outcome of the patients ensuring completeness of the surgery. CISS should be routinely performed in the work-up of patients with tethered cord syndrome.


Assuntos
Cauda Equina , Defeitos do Tubo Neural , Cauda Equina/diagnóstico por imagem , Cauda Equina/cirurgia , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Defeitos do Tubo Neural/diagnóstico por imagem , Defeitos do Tubo Neural/cirurgia
6.
Can Assoc Radiol J ; 72(1): 175-179, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32698669

RESUMO

BACKGROUND: Portable chest radiograph for COVID-19 positive patients and persons under investigation can be acquired through glass doors or walls of isolation rooms to limit exposure to the pathogen and conserve resources. PURPOSE: To report our initial experience with acquiring portable chest radiographs through glass doors of isolation rooms. METHODS: Only 1 of 2 radiology technologist team members donned personal protective equipment and stayed inside the isolation room, while the second technologist and the radiography unit remained outside during the procedure. First hundred radiographs acquired through glass at the emergency department of our institute formed the "through glass radiograph" group. Hundred consecutive portable chest radiographs performed in a conventional manner formed the "conventional radiograph" group for comparison. Imaging database and feedback from operations leader were used to identify occurrences of a failed procedure. Suggestion of repeating the study and comments related to quality of the study were recorded from the reports of the staff radiologist. RESULTS: There was no instance of failed acquisition, nondiagnostic examination, or suggestion of repetition in both groups. No significant difference in the number of reports with quality related remarks (P > .05) was found between the 2 groups. Radiography through glass doors was associated with increased suboptimal positioning related remarks in radiology reports (P < .05). No significant association was identified among other comments about image quality. CONCLUSION: Our initial clinical experience suggests that the acquisition of portable chest radiographs through the glass doors of isolation rooms is technically feasible and results in diagnostic quality studies.


Assuntos
COVID-19/diagnóstico por imagem , Controle de Infecções/métodos , Exposição Ocupacional/prevenção & controle , Radiografia Torácica/métodos , Radiografia Torácica/normas , Adulto , Idoso , COVID-19/prevenção & controle , Serviço Hospitalar de Emergência , Feminino , Vidro , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Estudos Retrospectivos , SARS-CoV-2 , Tecnologia Radiológica/métodos , Centros de Atenção Terciária
7.
J Cardiovasc Magn Reson ; 22(1): 9, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31996239

RESUMO

BACKGROUND: Investigation of the myocardial strain characteristics of the left ventricular non-compaction (LVNC) phenotype with cardiovascular magnetic resonance (CMR) feature tracking. METHODS: CMR cine balanced steady-state free precession data sets of 59 retrospectively identified LVNC phenotype patients (40 years, IQR: 28-50 years; 51% male) and 36 healthy subjects (39 years, IQR: 30-47 years; 44% male) were evaluated for LV volumes, systolic function and mass. Hypertrabeculation in patients and healthy subjects was evaluated against established CMR diagnostic criteria. Global circumferential strain (GCS), global radial strain (GRS) and global longitudinal strain (GLS) were evaluated with feature-tracking software. Subgroup analyses were performed in patients (n = 25) and healthy subjects (n = 34) with normal LV volumetrics, and with healthy subjects (n = 18) meeting at least one LVNC diagnostic criteria. RESULTS: All LVNC phenotype patients, as well as a significant proportion of healthy subjects, met morphology-based CMR diagnostic criteria: non-compacted (NC): compacted myocardial diameter ratio > 2.3 (100% vs. 19.4%), NC mass > 20% (100% vs. 44.4%) and > 25% (100% vs. 13.9%), and NC mass indexed to body surface area > 15 g/m2 (100% vs. 41.7%). LVNC phenotype patients demonstrated reduced GRS (26.4% vs. 37.1%; p < 0.001), GCS (- 16.5% vs. -20.5%; p < 0.001) and GLS (- 14.6% vs. -17.1%; p < 0.001) compared to healthy subjects, with statistically significant differences persisting on subgroup comparisons of LVNC phenotype patients with healthy subjects meeting diagnostic criteria. GCS also demonstrated independent and incremental diagnostic value beyond each of the morphology-based CMR diagnostic criteria. CONCLUSIONS: LVNC phenotype patients demonstrate impaired strain by CMR feature tracking, also present on comparison of subjects with normal LV volumetrics meeting diagnostic criteria. The high proportion of healthy subjects meeting morphology-based CMR diagnostic criteria emphasizes the important potential complementary diagnostic value of strain in differentiating LVNC from physiologic hypertrabeculation.


Assuntos
Miocárdio Ventricular não Compactado Isolado/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Função Ventricular Esquerda , Adulto , Bases de Dados Factuais , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Miocárdio Ventricular não Compactado Isolado/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Valor Preditivo dos Testes , Estudos Retrospectivos
8.
Emerg Radiol ; 27(5): 527-532, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32418149

RESUMO

Due to a combination of increasing indications for MR imaging, increased MRI accessibility, and extensive global armed conflict over the last few decades, an increasing number of patients now and in the future will present with retained metallic ballistic debris of unknown composition. To date, there are no guidelines on how to safely image these patients which may result in patients who would benefit from MRI not receiving it. In this article, we review the current literature pertaining to the MRI safety of retained ballistic materials and present the process we use to safely image these patients.


Assuntos
Corpos Estranhos/diagnóstico por imagem , Imageamento por Ressonância Magnética , Metais , Polímeros , Ferimentos por Arma de Fogo/diagnóstico por imagem , Humanos
9.
Can Assoc Radiol J ; 71(3): 335-343, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32103684

RESUMO

Here in Canada, we often think of gun violence as confined to conflict zones, terrorism, and more of a problem for our southern neighbor. However, in recent years, it has also become a Canadian problem with increased gun violence related to criminal activity presenting in daily practice. Radiologists play a critical role in the evaluation of ballistic trauma and must therefore be familiar with both the common and uncommon patterns of ballistic injury. In this article, we review the mechanisms of ballistic trauma as well as their resultant injury patterns in order to guide image interpretation.


Assuntos
Tomografia Computadorizada por Raios X/métodos , Ferimentos por Arma de Fogo/diagnóstico por imagem , Meios de Contraste , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética/métodos , Física , Ultrassonografia/métodos
10.
Can Assoc Radiol J ; 71(3): 253-265, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32106693

RESUMO

Dual-energy computed tomography (CT) is a promising tool with increasing availability and multiple emerging and established clinical applications in neuroradiology. With its ability to allow characterization of materials based on their differential attenuation when imaged at two different energy levels, dual-energy CT can help identify the composition of brain, neck, and spinal components. Virtual monoenergetic imaging allows a range of simulated single energy-level reconstructions to be created with postprocessing. Low-energy reconstructions can aid identification of edema, ischemia, and subtle lesions due to increased soft tissue contrast as well as increasing contrast-to-noise ratios on angiographic imaging. Higher energy reconstructions can reduce image artifact from dental amalgam, aneurysm clips and coils, spinal hardware, dense contrast, and dense bones. Differentiating iodine from hemorrhage may help guide management of patients after thrombectomy and aid diagnosis of enhancing tumors within parenchymal hemorrhages. Iodine quantification may predict hematoma expansion in aneurysmal bleeds and outcomes in traumatic brain injury. Calcium and bone subtraction can be used to distinguish hemorrhage from brain parenchymal mineralization as well as improving visualization of extra-axial lesions and vessels adjacent to dense plaque or skull. This article reviews the basics of dual-energy CT and highlights many of its clinical applications in the evaluation of acute neurological presentations.


Assuntos
Neuroimagem/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Humanos
11.
Can Assoc Radiol J ; 71(3): 396-402, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32157904

RESUMO

The use of diagnostic imaging studies in the emergency setting has increased dramatically over the past couple of decades. The emergency imaging of pregnant and lactating patients poses unique challenges and calls upon the crucial role of radiologists as consultants to the referring physician to guide appropriate use of imaging tests, minimize risk, ensure timely management, and occasionally alleviate unwarranted trepidation. A clear understanding of the risks and benefits involved with various imaging tests in this patient population is vital to achieve this. This review discusses the different safety and appropriateness issues that could arise with the use of ionizing radiation, iodinated-, and gadolinium-based contrast media and radiopharmaceuticals in pregnant and lactating patients. Special considerations such as trauma imaging, safety concerns with magnetic resonance imaging and ultrasound, management of claustrophobia, contrast extravasation, and allergic reactions are also reviewed. The consent process for these examinations has also been described.


Assuntos
Emergências , Feto/efeitos da radiação , Lactação/efeitos dos fármacos , Complicações na Gravidez/diagnóstico por imagem , Exposição à Radiação/prevenção & controle , Proteção Radiológica/métodos , Ferimentos e Lesões/diagnóstico por imagem , Meios de Contraste/efeitos adversos , Feminino , Humanos , Transtornos Fóbicos/prevenção & controle , Gravidez , Compostos Radiofarmacêuticos/efeitos adversos , Gestão da Segurança
14.
J Cardiovasc Magn Reson ; 21(1): 45, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31366357

RESUMO

BACKGROUND: Cardiac involvement is common and is the leading cause of mortality in Fabry disease (FD). We explored the association between cardiovascular magnetic resonance (CMR) myocardial strain, T1 mapping, late gadolinium enhancement (LGE) and left ventricular hypertrophy (LVH) in patients with FD. METHODS: In this prospective study, 38 FD patients (45.0 ± 14.5 years, 37% male) and 8 healthy controls (40.1 ± 13.7 years, 63% male) underwent 3 T CMR including cine balanced steady-state free precession (bSSFP), LGE and modified Look-Locker Inversion recovery (MOLLI) T1 mapping. Global longitudinal (GLS) and circumferential (GCS) strain and base-to-apex longitudinal strain (LS) and circumferential strain (CS) gradients were derived from cine bSSFP images using feature tracking analysis. RESULTS: Among FD patients, 8 had LVH (FD LVH+, 21%) and 17 had LGE (FD LGE+, 45%). Nineteen FD patients (50%) had neither LVH nor LGE (FD LVH- LGE-). None of the healthy controls had LVH or LGE. FD patients and healthy controls did not differ significantly with respect to GLS (- 15.3 ± 3.5% vs. - 16.3 ± 1.5%, p = 0.45), GCS (- 19.4 ± 3.0% vs. -19.5 ± 2.9%, p = 0.84) or base-to-apex LS gradient (7.5 ± 3.8% vs. 9.3 ± 3.5%, p = 0.24). FD patients had significantly lower base-to-apex CS gradient (2.1 ± 3.7% vs. 6.5 ± 2.2%, p = 0.002) and native T1 (1170.2 ± 37.5 ms vs. 1239.0 ± 18.0 ms, p < 0.001). Base-to-apex CS gradient differentiated FD LVH- LGE- patients from healthy controls (OR 0.42, 95% CI: 0.20 to 0.86, p = 0.019), even after controlling for native T1 (OR 0.24, 95% CI: 0.06 to 0.99, p = 0.049). In a nested logistic regression model with native T1, model fit was significantly improved by the addition of base-to-apex CS gradient (χ2(df = 1) = 11.04, p < 0.001). Intra- and inter-observer agreement were moderate to good for myocardial strain parameters: GLS (ICC 0.849 and 0.774, respectively), GCS (ICC 0.831 and 0.833, respectively), and base-to-apex CS gradient (ICC 0.737 and 0.613, respectively). CONCLUSIONS: CMR reproducibly identifies myocardial strain abnormalities in FD. Loss of base-to-apex CS gradient may be an early marker of cardiac involvement in FD, with independent and incremental value beyond native T1.


Assuntos
Cardiomiopatias/diagnóstico , Meios de Contraste/administração & dosagem , Doença de Fabry/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/diagnóstico , Imagem Cinética por Ressonância Magnética , Contração Miocárdica , Compostos Organometálicos/administração & dosagem , Função Ventricular Esquerda , Remodelação Ventricular , Adulto , Cardiomiopatias/fisiopatologia , Estudos de Casos e Controles , Doença de Fabry/fisiopatologia , Feminino , Humanos , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes
16.
Radiology ; 288(2): 398-406, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29688154

RESUMO

Purpose To compare left ventricular (LV) and right ventricular (RV) 3.0-T cardiac magnetic resonance (MR) imaging T1 values in Anderson-Fabry disease (AFD) and hypertrophic cardiomyopathy (HCM) and evaluate the diagnostic value of native T1 values beyond age, sex, and conventional imaging features. Materials and Methods For this prospective study, 30 patients with gene-positive AFD (37% male; mean age ± standard deviation, 45.0 years ± 14.1) and 30 patients with HCM (57% male; mean age, 49.3 years ± 13.5) were prospectively recruited between June 2016 and September 2017 to undergo cardiac MR imaging T1 mapping with a modified Look-Locker inversion recovery (MOLLI) acquisition scheme at 3.0 T (repetition time msec/echo time msec, 280/1.12; section thickness, 8 mm). LV and RV T1 values were evaluated. Statistical analysis included independent samples t test, receiver operating characteristic curve analysis, multivariable logistic regression, and likelihood ratio test. Results Septal LV, global LV, and RV native T1 values were significantly lower in AFD compared with those in HCM (1161 msec ± 47 vs 1296 msec ± 55, respectively [P < .001]; 1192 msec ± 52 vs 1268 msec ± 55 [P < .001]; and 1221 msec ± 54 vs 1271 msec ± 37 [P = .001], respectively). A septal LV native T1 cutoff point of 1220 msec or lower distinguished AFD from HCM with sensitivity of 97%, specificity of 93%, and accuracy of 95%. Septal LV native T1 values differentiated AFD from HCM after adjustment for age, sex, and conventional imaging features (odds ratio, 0.94; 95% confidence interval: 0.91, 0.98; P = < .001). In a nested logistic regression model with age, sex, and conventional imaging features, model fit was significantly improved by the addition of septal LV native T1 values (χ2 [df = 1] = 33.4; P < .001). Conclusion Cardiac MR imaging native T1 values at 3.0 T are significantly lower in patients with AFD compared with those with HCM and provide independent and incremental diagnostic value beyond age, sex, and conventional imaging features. © RSNA, 2018.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Doença de Fabry/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Cardiomiopatia Hipertrófica/fisiopatologia , Diagnóstico Diferencial , Doença de Fabry/fisiopatologia , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio , Estudos Prospectivos
18.
Dalton Trans ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912924

RESUMO

DNA being the necessary element in cell regeneration, controlled cellular apoptosis via DNA binding/cleaving is considered an approach to combat cancer cells. The widely prescribed metallodrug cisplatin has shown interactions with the guanine-N7 center, and a plethora of complexes are continually developed to enhance crosslinking properties as well as covalent and non-covalent interactions. Two pentadentate ligands, L1 (1-(6-(1H-benzo[d]imidazol-2-yl)pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine) and L2 (1-(6-(1-methyl-1H-benzo[d]imidazol-2-yl)pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine), were synthesized together with their respective copper(II) complexes [1](ClO4)2 and [2](ClO4)2, which crystallized in a trigonal bipyramidal fashion. Different analytical and spectroscopic methods confirmed their formation, and their redox behaviour was also examined. The interactions of salmon sperm DNA (ss-DNA) with these two complexes were explored using absorbance spectroscopy, and they both exhibited a binding affinity (Kb) of ∼104 M-1. Fluorescence quenching experiments with ethidium bromide (EB)-bound DNA (EB-DNA) were also performed, and Stern-Volmer constant (KSV) values of 6.93 × 103 and 2.34 × 104 M-1 for [1](ClO4)2 and [2](ClO4)2, respectively, were obtained. Furthermore, DNA conformational changes due to the interactions of both complexes were validated via circular dichroism. We also assessed the DNA cleavage property of these complexes, which resulted in the linearization of circular plasmid DNA. This finding was supported by studying the growth of MDA-MB-231 breast cancer cells upon treatment with both Cu(II) complexes; IC50 values of 5.34 ± 1.02 µM and 0.83 ± 0.18 µM were obtained for [1](ClO4)2 and [2](ClO4)2, respectively. This validates their affinity towards DNA, and these insights can be further utilized for non-platinum based economical metallodrug development based on first row transition metals.

19.
J Med Imaging Radiat Sci ; 55(3): 101433, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38941784

RESUMO

OBJECTIVE: Intravenous contrast injection protocol for certain CT studies at our institution was revised in June 2022 in response to the global shortage of iohexol. This included CT head studies performed for neuro-navigation (contrast dose from 90 mL to 70 mL). The quality of these studies was assessed. METHODS: Consecutive CT scans before (n = 32) and after (n = 32) contrast dose reduction were reviewed. Demographic data was obtained from the chart. Subjective observations made by two radiologists in consensus included overall study quality (Likert scale of 1 to 5) and lesion location, margins and internal characteristics that were compared with MRI findings (reference standard) using Fisher's exact test. Superior sagittal sinus attenuation, used as an objective measurement of enhancement, and lesion size were compared using Student's t-test. The institutional database was searched for any study requiring repetition or deemed non-diagnostic. RESULTS/DISCUSSION: The average age (61.1 ± 12.7 years and 61.6 ± 14.9 years) and body surface area (BSA) (1.9 ± 0.3 m2 and 1.9 ± 0.02 m2) was not significantly different (p > 0.05) between groups. There was no significant difference (p > 0.05) in objective or subjective enhancement between the two groups. There was no significant difference between CT and MRI for lesion size, location, number, margins and internal enhancement characteristics in the two groups. No study required repetition or was reported as non-diagnostic. There was no adverse comment about study quality in operative notes. CONCLUSION: Reduced contrast dose neuro-navigation CT head studies are not different in quality compared to the conventional studies.

20.
Dalton Trans ; 53(3): 1163-1177, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38105760

RESUMO

Mixed ligand copper(II) complexes [Cu(L1)(bpy)](ClO4)21 and [Cu(L2)(bpy)](ClO4)22 (where L1 = 1-(anthracen-9-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine, L2 = 1-(pyren-1-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine and bpy = 2,2'-bipyridine) were synthesised and characterised thoroughly via different analytical and spectroscopic techniques i.e., UV-vis spectroscopy, fluorescence spectroscopy, FT-IR spectroscopy, HRMS and EPR spectroscopy. The molecular structures of the synthesised complexes were obtained using the single-crystal X-ray diffraction technique. Both complexes exhibited penta-coordinated and acquired distorted square pyramidal geometry. The redox behaviour of complexes 1 and 2 was investigated by employing cyclic voltammetry. The DNA binding study was carried out by UV-vis spectrophotometry using double-stranded salmon sperm DNA (ds-ss-DNA). The binding constant (Kb) values of 1 and 2 were 0.11 × 104 M-1 and 1.05 × 104 M-1, respectively, which indicates that 2 has better binding ability than 1. This might be due to the higher conjugative abilities with the extended surface area of the aromatic pyrene ring compared to the anthracene moiety. The fluorescence quenching experiments were also performed with EB bound DNA (EB-DNA) and Stern-Volmer constant (KSV) values were calculated as 1.23 × 105 M-1 and 1.39 × 105 M-1 for 1 and 2, respectively, suggesting that 2 showed stronger interaction with ss-DNA than 1. The molecular docking data support the DNA-binding studies, with the sites and mode of interactions against B-DNA varying with 1 and 2. Evaluation of the DNA binding properties of the complexes to linearized plasmid DNA indicated that 2 had modest DNA binding properties, which is a pre-requisite for a genotoxic agent. The effect of 1 and 2 on cell survival was analysed using HeLa cells by MTT assay and it was observed that the IC50 values of 1 and 2 were 43.7 µM and 18.6 µM, respectively. Our study paves the way for the designing of bio-inspired novel mixed metal complexes, which shows promising results for further exploration of molecular and mechanistic studies towards the development of non-platinum based economical metallodrugs.


Assuntos
Complexos de Coordenação , Cobre , Masculino , Humanos , Cobre/química , Simulação de Acoplamento Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Células HeLa , Sêmen/metabolismo , DNA/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Cristalografia por Raios X , Ligantes
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