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1.
Eur Radiol ; 33(10): 6726-6735, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37178203

RESUMO

OBJECTIVES: We evaluate MR radiomics and develop machine learning-based classifiers to predict MYCN amplification in neuroblastomas. METHODS: A total of 120 patients with neuroblastomas and baseline MR imaging examination available were identified of whom 74 (mean age ± standard deviation [SD] of 6 years and 2 months ± 4 years and 9 months; 43 females and 31 males, 14 MYCN amplified) underwent imaging at our institution. This was therefore used to develop radiomics models. The model was tested in a cohort of children with the same diagnosis but imaged elsewhere (n = 46, mean age ± SD: 5 years 11 months ± 3 years 9 months, 26 females and 14 MYCN amplified). Whole tumour volumes of interest were adopted to extract first-order histogram and second-order radiomics features. Interclass correlation coefficient and maximum relevance and minimum redundancy algorithm were applied for feature selection. Logistic regression, support vector machine, and random forest were employed as the classifiers. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic accuracy of the classifiers on the external test set. RESULTS: The logistic regression model and the random forest both showed an AUC of 0.75. The support vector machine classifier obtained an AUC of 0.78 on the test set with a sensitivity of 64% and a specificity of 72%. CONCLUSION: The study provides preliminary retrospective evidence demonstrating the feasibility of MRI radiomics in predicting MYCN amplification in neuroblastomas. Future studies are needed to explore the correlation between other imaging features and genetic markers and to develop multiclass predictive models. KEY POINTS: • MYCN amplification in neuroblastomas is an important determinant of disease prognosis. • Radiomics analysis of pre-treatment MR examinations can be used to predict MYCN amplification in neuroblastomas. • Radiomics machine learning models showed good generalisability to external test set, demonstrating reproducibility of the computational models.


Assuntos
Imageamento por Ressonância Magnética , Neuroblastoma , Masculino , Feminino , Criança , Humanos , Proteína Proto-Oncogênica N-Myc/genética , Estudos Retrospectivos , Reprodutibilidade dos Testes , Imageamento por Ressonância Magnética/métodos , Neuroblastoma/diagnóstico por imagem , Neuroblastoma/genética
2.
Child Neurol Open ; 10: 2329048X231157147, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36910596

RESUMO

Callosal agenesis is a complex condition with disruption in the steps such as cellular proliferation, migration, axonal growth, guidance, or glial patterning at the midline. Agenesis of the corpus callosum (AgCC) is associated with diverse midline craniofacial malformations affecting the frontal-cranial and midface skeleton. Diagnosing midline abnormalities prenatally can be challenging, especially in twin pregnancies, due to poor resolution of skull base structures on fetal MRI, basal cephalocele could be mistaken for fluid in the nasopharynx, motion limitation, and fetal positioning. Our case highlights the importance of evaluation for other associated midline anomalies when there is callosal agenesis.

4.
Cerebellum ; 21(1): 116-131, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34052969

RESUMO

Evaluation of ataxia in children is challenging in clinical practice. This is particularly true for highly heterogeneous conditions such as primary mitochondrial disorders (PMD). This study aims to explore cerebellar and brain abnormalities identified on MRI as potential predictors of ataxia in patients with PMD and, likewise, to determine the effect of the patient's genetic profile on these predictors as well as determination of the temporal relationship of clinical ataxia with MRI findings. We evaluated clinical, radiological, and genetic characteristics of 111 PMD patients younger than 21 years of age at The Children's Hospital of Philadelphia. Data was extracted from charts. Blinded radiological evaluations were carried out by experienced neuroradiologists. Multivariate logistic regression and generalized equation estimates were used for analysis. Ataxia was identified in 41% of patients. Cerebellar atrophy or putaminal involvement with mitochondrial DNA (mtDNA) mutations (OR 1.18, 95% CI 1.1-1.3, p < 0.001) and nuclear DNA mutation with no atrophy of the cerebellum (OR 1.14, 95% CI 1.0-1.3, p = 0.007) predicted an increased likelihood of having ataxia per year of age. Central tegmental tract predicted the presence of ataxia independent of age and pathogenic variant origin (OR 9.8, 95% CI 2-74, p = 0.009). Ataxia tended to precede the imaging finding of cerebellar atrophy. Cerebellar atrophy and putaminal involvement on MRI of pediatric-onset PMD may predict the presence of ataxia with age in patients with mtDNA mutations. This study provides predicted probabilities of having ataxia per year of age that may help in family counseling and future research of the population.


Assuntos
Ataxia Cerebelar , Doenças Mitocondriais , Atrofia/patologia , Ataxia Cerebelar/genética , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Criança , Humanos , Imageamento por Ressonância Magnética/métodos , Doenças Mitocondriais/diagnóstico por imagem , Doenças Mitocondriais/genética
5.
Early Hum Dev ; 163: 105470, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34563832

RESUMO

Developmental trends between 3 and 24 months were assessed in 194 normocephalic infants with prenatal Zika virus exposure. Bayley Scales of Infant and Toddler Development Screening Test-3rd Edition cognitive scores remained in the typical range. Communication skills developed at a slower rate suggesting that neurodevelopmental delays may emerge at older ages.


Assuntos
Craniossinostoses , Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus , Desenvolvimento Infantil , Comunicação , Feminino , Humanos , Lactente , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Estudos Prospectivos , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia
6.
Radiol Bras ; 54(3): 141-147, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34108760

RESUMO

OBJECTIVE: To compare fetuses with intrauterine growth restriction (IUGR) and those with normal growth, in terms of skull and brain measurements obtained by magnetic resonance imaging (MRI). MATERIALS AND METHODS: This was a prospective cohort study including 26 single fetuses (13 with IUGR and 13 with normal growth), evaluated from 26 to 38 weeks of gestation. Using MRI, we measured skull and brain biparietal diameters (BPDs); skull and brain occipitofrontal diameters (OFDs); corpus callosum length and area; transverse cerebellar diameter; extracerebral cerebrospinal fluid (eCSF); and right and left interopercular distances (IODs). RESULTS: The following were significantly smaller in IUGR fetuses than in control fetuses: skull BPD (76.9 vs. 78.2 mm; p = 0.0029); brain BPD (67.8 vs. 71.6 mm; p = 0.0064); skull OFD (93.6 vs. 95 mm; p = 0.0010); eCSF (5.5 vs. 8.2 mm; p = 0.0003); right IOD (9.8 vs. 13.9 mm; p = 0.0023); and left IOD (11.8 vs. 16.3 mm; p = 0.0183). The skull BPD/eCSF, brain BPD/eCSF, skull OFD/eCSF, and brain OFD/eCSF ratios were also lower in IUGR fetuses. CONCLUSION: IUGR fetuses had smaller OFD and BPD, both skull and brain, and less eCSF when compared to normal growth fetuses.


OBJETIVO: Comparar medidas do crânio e encéfalo por meio da ressonância magnética (RM) de fetos com restrição do crescimento intrauterino (RCIU) e com crescimento adequado. MATERIAIS E MÉTODOS: Realizou-se um estudo de coorte prospectivo com 13 fetos com RCIU e 13 controles entre 26 e 38 semanas. Foram realizadas as seguintes medidas por RM: diâmetro biparietal (DBP) e diâmetro occipitofrontal (DOF) cerebral e ósseo, comprimento e área do corpo caloso (CPC), diâmetro transverso do cerebelo, líquido cerebroespinhal (LCE) extracerebral e distância interopercular (DIO) direita e esquerda. RESULTADOS: Observaram-se diferenças significativas nas medidas do DBP ósseo (76,9 vs. 78,2 mm; p = 0,0029), DBP cerebral (67,8 vs. 71,6 mm; p = 0,0064) e DOF ósseo (93,6 vs. 95 mm; p = 0,0010) em fetos com RCIU em relação aos fetos com crescimento normal. Observaram-se, ainda, diferenças significativas nas médias do LCE extracerebral (5,5 vs. 8,2 mm; p = 0,0003) e DIO direita (9,8 vs. 13,9 mm; p = 0,0023) e esquerda (11,8 vs. 16,3 mm; p = 0,0183) em fetos com RCIU em relação aos controles. Fetos com RCIU e normais tiveram diferenças entre DBP ósseo/LCE, DBP cerebral/LCE, DOF/LEC, e DOF cerebral/LCE. CONCLUSÃO: Fetos com RCIU tiveram menores DBP e DOF, ambos crânio e encéfalo, e menor LCE extracerebral que fetos com crescimento adequado.

7.
Viruses ; 13(4)2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924066

RESUMO

Confirming ZIKV congenital infection is challenging because viral RNA is infrequently detected. We compared the presence of anti-ZIKV-IgM and the persistence of anti-ZIKV-IgG antibodies over 18 months in two cohorts of infants born to ZIKV-infected mothers: Cohort one: 30 infants with typical microcephaly or major brain abnormalities (Congenital Zika Syndrome-CZS); Cohort two: 123 asymptomatic infants. Serum samples obtained within 6 months of age were tested for anti-ZIKV-IgM. Anti-ZIKV-IgG was quantified in sequential samples collected at birth, 3-6 weeks, 3, 6, 12, and 18 months. ZIKV-RNA was never detected postnatally. Anti-ZIKV-IgM antibodies were detected at least once in 15/25 (60.0%; 95%CI: 38.7-78.9) infants with CZS and in 2/115 (1.7%; 95%CI: 0.2-6.1) asymptomatic infants. Although anti-ZIKV-IgG was always positive within 3-6 weeks of age, IgG levels decreased similarly over time in both cohorts. IgG levels decreased similarly in ZIKV-IgM-positive and ZIKV-IgM-negative CZS infants. Differently from other congenital infections, IgM would fail to diagnose 40% of severely symptomatic infants, and the persistence of IgG is not a useful marker for discriminating congenital infection among infants exposed to maternal ZIKV infection.


Assuntos
Anticorpos Antivirais/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Complicações Infecciosas na Gravidez , Infecção por Zika virus/congênito , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Infecção por Zika virus/imunologia
9.
Radiol Bras ; 53(6): 424-429, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304012

RESUMO

Portal vein thrombosis refers to complete or partial obstruction of the portal venous system, in the intrahepatic or extrahepatic venous tract or even in the splenic or superior mesenteric veins. This common and potentially fatal condition can develop in various clinical contexts, especially those of liver cirrhosis, hepatocellular carcinoma, and other solid tumors. Certain characteristics, such as the time since the onset of the thrombus (acute or chronic), its biology (hematic or tumoral), the presence of collateral vessels, and the magnetic resonance imaging aspects, are important components of a thorough, careful analysis, as well as informing decisions regarding the appropriate therapeutic strategy. Here, we present a brief review of the anatomy of the portal venous system and a systematic approach to analyzing the condition, using a mnemonic (ABCD, for age, biology, collaterals, and diffusion). We discuss the various imaging methods and illustrate our discussion with images selected from the case files archived at our facility.


Trombose da veia porta refere-se à obstrução completa ou parcial do sistema venoso portal, localizada nos tratos venosos intra-hepáticos ou extra-hepáticos e até mesmo nas veias esplênica ou mesentérica superior. Vários contextos clínicos podem ser responsáveis pelo desenvolvimento desta condição frequente e potencialmente fatal, especialmente a cirrose hepática, o carcinoma hepatocelular e outros tumores sólidos. Algumas características como o tempo de aparecimento do trombo (agudo ou crônico), sua biologia (hemático ou tumoral), a presença de vasos colaterais e o seu comportamento na ressonância magnética são importantes para uma análise completa e criteriosa, assim como para o gerenciamento adequado da estratégia terapêutica. No presente artigo apresentamos breve revisão da anatomia do trato venoso portal, seguida de uma abordagem sistemática usando um mnemônico (ABCD) para análise da trombose da veia porta por diferentes métodos de imagem, utilizando imagens de casos selecionados do arquivo de ensino do nosso serviço.

10.
Radiol. bras ; 53(6): 424-429, Nov.-Dec. 2020. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1136109

RESUMO

Abstract Portal vein thrombosis refers to complete or partial obstruction of the portal venous system, in the intrahepatic or extrahepatic venous tract or even in the splenic or superior mesenteric veins. This common and potentially fatal condition can develop in various clinical contexts, especially those of liver cirrhosis, hepatocellular carcinoma, and other solid tumors. Certain characteristics, such as the time since the onset of the thrombus (acute or chronic), its biology (hematic or tumoral), the presence of collateral vessels, and the magnetic resonance imaging aspects, are important components of a thorough, careful analysis, as well as informing decisions regarding the appropriate therapeutic strategy. Here, we present a brief review of the anatomy of the portal venous system and a systematic approach to analyzing the condition, using a mnemonic (ABCD, for age, biology, collaterals, and diffusion). We discuss the various imaging methods and illustrate our discussion with images selected from the case files archived at our facility.


Resumo Trombose da veia porta refere-se à obstrução completa ou parcial do sistema venoso portal, localizada nos tratos venosos intra-hepáticos ou extra-hepáticos e até mesmo nas veias esplênica ou mesentérica superior. Vários contextos clínicos podem ser responsáveis pelo desenvolvimento desta condição frequente e potencialmente fatal, especialmente a cirrose hepática, o carcinoma hepatocelular e outros tumores sólidos. Algumas características como o tempo de aparecimento do trombo (agudo ou crônico), sua biologia (hemático ou tumoral), a presença de vasos colaterais e o seu comportamento na ressonância magnética são importantes para uma análise completa e criteriosa, assim como para o gerenciamento adequado da estratégia terapêutica. No presente artigo apresentamos breve revisão da anatomia do trato venoso portal, seguida de uma abordagem sistemática usando um mnemônico (ABCD) para análise da trombose da veia porta por diferentes métodos de imagem, utilizando imagens de casos selecionados do arquivo de ensino do nosso serviço.

11.
Pediatr Radiol ; 50(10): 1424-1447, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32734340

RESUMO

This article is the first of a two-part series on intracranial calcification in childhood. Intracranial calcification can be either physiological or pathological. Physiological intracranial calcification is not an expected neuroimaging finding in the neonatal or infantile period but occurs, as children grow older, in the pineal gland, habenula, choroid plexus and occasionally the dura mater. Pathological intracranial calcification can be broadly divided into infectious, congenital, endocrine/metabolic, vascular and neoplastic. The main goals in Part 1 are to discuss the chief differences between physiological and pathological intracranial calcification, to discuss the histological characteristics of intracranial calcification and how intracranial calcification can be detected across neuroimaging modalities, to emphasize the importance of age at presentation and intracranial calcification location, and to propose a comprehensive neuroimaging approach toward the differential diagnosis of the causes of intracranial calcification. Finally, in Part 1 the authors discuss the most common causes of infectious intracranial calcification, especially in the neonatal period, and congenital causes of intracranial calcification. Various neuroimaging modalities have distinct utilities and sensitivities in the depiction of intracranial calcification. Age at presentation, intracranial calcification location, and associated neuroimaging findings are useful information to help narrow the differential diagnosis of intracranial calcification. Intracranial calcification can occur in isolation or in association with other neuroimaging features. Intracranial calcification in congenital infections has been associated with clastic changes, hydrocephalus, chorioretinitis, white matter abnormalities, skull changes and malformations of cortical development. Infections are common causes of intracranial calcification, especially neonatal TORCH (toxoplasmosis, other [syphilis, varicella-zoster, parvovirus B19], rubella, cytomegalovirus and herpes) infections.


Assuntos
Encefalopatias/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Calcificação Fisiológica , Calcinose/diagnóstico por imagem , Neuroimagem/métodos , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
12.
Pediatr Radiol ; 50(10): 1448-1475, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32642802

RESUMO

This article is the second of a two-part series on intracranial calcification in childhood. In Part 1, the authors discussed the main differences between physiological and pathological intracranial calcification. They also outlined histological intracranial calcification characteristics and how these can be detected across different neuroimaging modalities. Part 1 emphasized the importance of age at presentation and intracranial calcification location and proposed a comprehensive neuroimaging approach toward the differential diagnosis of the causes of intracranial calcification. Pathological intracranial calcification can be divided into infectious, congenital, endocrine/metabolic, vascular, and neoplastic. In Part 2, the chief focus is on discussing endocrine/metabolic, vascular, and neoplastic intracranial calcification etiologies of intracranial calcification. Endocrine/metabolic diseases causing intracranial calcification are mainly from parathyroid and thyroid dysfunction and inborn errors of metabolism, such as mitochondrial disorders (MELAS, or mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes; Kearns-Sayre; and Cockayne syndromes), interferonopathies (Aicardi-Goutières syndrome), and lysosomal disorders (Krabbe disease). Specific noninfectious causes of intracranial calcification that mimic TORCH (toxoplasmosis, other [syphilis, varicella-zoster, parvovirus B19], rubella, cytomegalovirus, and herpes) infections are known as pseudo-TORCH. Cavernous malformations, arteriovenous malformations, arteriovenous fistulas, and chronic venous hypertension are also known causes of intracranial calcification. Other vascular-related causes of intracranial calcification include early atherosclerosis presentation (children with risk factors such as hyperhomocysteinemia, familial hypercholesterolemia, and others), healed hematoma, radiotherapy treatment, old infarct, and disorders of the microvasculature such as COL4A1- and COL4A2-related diseases. Intracranial calcification is also seen in several pediatric brain tumors. Clinical and familial information such as age at presentation, maternal exposure to teratogens including viruses, and association with chromosomal abnormalities, pathogenic genes, and postnatal infections facilitates narrowing the differential diagnosis of the multiple causes of intracranial calcification.


Assuntos
Encefalopatias/diagnóstico por imagem , Encefalopatias/etiologia , Calcinose/diagnóstico por imagem , Calcinose/etiologia , Neuroimagem/métodos , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
13.
Top Magn Reson Imaging ; 27(6): 503-514, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30516697

RESUMO

Abusive head trauma (AHT) is a form of inflicted head injury. AHT is more frequent in 2-year-old or younger children. It is an important cause of neurological impairment and the major cause of death from head trauma in this age group. Brain magnetic resonance imaging allows the depiction of retinal hemorrhages, injured bridging veins, and identifying and localizing extra- and intra-axial bleeds, contusions, lacerations, and strokes. The diagnosis of AHT is a multidisciplinary team effort which includes a careful evaluation of social, clinical, laboratory, and radiological findings. Notwithstanding, the introduction in the current clinical practice of high-resolution techniques is adding forensic evidence to the recognition of AHT.


Assuntos
Maus-Tratos Infantis/diagnóstico , Traumatismos Craniocerebrais/diagnóstico por imagem , Traumatismos Oculares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Pré-Escolar , Olho/diagnóstico por imagem , Humanos , Lactente
16.
J Addict Med ; 11(5): 405-407, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28614161

RESUMO

: Cerebrovascular events associated with marijuana use have been reported previously. This association is plausible, but not well-established yet. A 14-year-old girl, long-term heavy cannabis user, presented with generalized tonic-clonic seizures and decreased level of consciousness a few hours after smoking cannabis. Brain magnetic resonance imaging showed multiple areas of acute, subacute and chronic ischemic lesions in the left frontal lobe, basal ganglia, and corpus callosum. History of other illicit drug use and other known causes of stroke were ruled out. Cannabis might cause stroke through direct effects on the cerebral blood circulation, orthostatic hypotension, vasculitis, vasospasm, and atrial fibrillation. Long-term daily use of marijuana in young people may cause serious damage to the cerebrovascular system.


Assuntos
Cannabis/efeitos adversos , Infarto Cerebral/induzido quimicamente , Infarto Cerebral/diagnóstico por imagem , Fumar Maconha/efeitos adversos , Convulsões/induzido quimicamente , Adolescente , Feminino , Humanos
17.
J Pediatr Endocrinol Metab ; 30(3): 253-276, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28170340

RESUMO

Adrenocortical tumors (ACT) in adulthood and childhood vary in clinical, histopathological, molecular, prognostic, and imaging aspects. ACT are relatively common in adults, as adenomas are often found incidentally on imaging. ACT are rare in children, though they have a significantly higher prevalence in the south and southeast regions of Brazil. In clinical manifestation, adults with ACT present more frequently with glucocorticoid overproduction (Cushing syndrome), mineralocorticoid syndromes (Conn syndrome), or the excess of androgens in women. Subclinical tumors are frequently diagnosed late, associated with compression symptoms of abdominal mass. In children, the usual presentation is the virilizing syndrome or virilizing association and hypercortisolism. Histopathological grading and ACT classification in malignant and benign lesions are different for adults and children. In adults, the described criteria are the Hough, Weiss, modified Weiss, and Van Slooten. These scores are not valid for children; there are other criteria, such as proposed by Wieneke and colleagues. In molecular terms, there is also a difference related to genetic alterations found in these two populations. This review discusses the imaging findings of ACT, aiming to characterize the present differences between ACT found in adults and children. We listed several differences between magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography-computed (PET-CT) and also performed a literature review, which focuses on studied age groups of published articles in the last 10 years regarding cortical neoplasm and imaging techniques. Published studies on ACT imaging in children are rare. It is important to stress that the majority of publications related to the differentiation of malignant and benign tumors are based almost exclusively on studies in adults. A minority of articles, however, studied adults and children together, which may not be appropriate.


Assuntos
Neoplasias do Córtex Suprarrenal/diagnóstico por imagem , Neoplasias do Córtex Suprarrenal/patologia , Imagem Multimodal/métodos , Imagem Multimodal/normas , Adolescente , Adulto , Feminino , Humanos , Masculino , Prognóstico
18.
Cancer Imaging ; 17(1): 6, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28187778

RESUMO

Cancer is the leading cause of natural death in the pediatric populations of developed countries, yet cure rates are greater than 70% when a cancer is diagnosed in its early stages. Recent advances in magnetic resonance imaging methods have markedly improved diagnostic and therapeutic approaches, while avoiding the risks of ionizing radiation that are associated with most conventional radiological methods, such as computed tomography and positron emission tomography/computed tomography. The advent of whole-body magnetic resonance imaging in association with the development of metabolic- and function-based techniques has led to the use of whole-body magnetic resonance imaging for the screening, diagnosis, staging, response assessment, and post-therapeutic follow-up of children with solid sporadic tumours or those with related genetic syndromes. Here, the advantages, techniques, indications, and limitations of whole-body magnetic resonance imaging in the management of pediatric oncology patients are presented.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias/diagnóstico por imagem , Imagem Corporal Total/métodos , Criança , Humanos , Estadiamento de Neoplasias , Pediatria
19.
Radiol. bras ; 49(6): 363-368, Nov.-Dec. 2016. graf
Artigo em Inglês | LILACS | ID: biblio-842415

RESUMO

Abstract Objective: To assess the feasibility and reliability of apparent diffusion coefficient (ADC) measurements of normal adrenal glands. Materials and methods: This was a retrospective study involving 32 healthy subjects, divided into two groups: prepubertal (PreP, n = 12), aged from 2 months to 12.5 years (4 males; 8 females); and postpubertal (PostP, n = 20), aged from 11.9 to 61 years (5 males; 15 females). Diffusion-weighted magnetic resonance imaging (DW-MRI) sequences were acquired at a 1.5 T scanner using b values of 0, 20, 500, and 1000 s/mm2. Two radiologists evaluated the images. ADC values were measured pixel-by-pixel on DW-MRI scans, and automatic co-registration with the ADC map was obtained. Results: Mean ADC values for the right adrenal glands were 1.44 × 10-3 mm2/s for the PreP group and 1.23 × 10-3 mm2/s for the PostP group, whereas they were 1.58 × 10-3 mm2/s and 1.32 × 10-3 mm2/s, respectively, for the left glands. ADC values were higher in the PreP group than in the PostP group (p < 0.05). Agreement between readers was almost perfect (intraclass correlation coefficient, 0.84-0.94; p < 0.05). Conclusion: Our results demonstrate the feasibility and reliability of performing DW-MRI measurements of normal adrenal glands. They could also support the feasibility of ADC measurements of small structures.


Resumo Objetivo: Avaliar se a medida do coeficiente de difusão aparente (CDA) das glândulas suprarrenais é factível e reprodutível. Materiais e métodos: Neste estudo foram incluídos, retrospectivamente, 32 indivíduos saudáveis divididos em dois grupos: pré-púbere (PreP) (n = 12; 2 meses a 12,5 anos; 4 masculinos e 8 femininos) e pós-púbere (PostP) (n = 20; 11,9-61 anos; 5 masculinos e 15 femininos). Imagens de difusão por ressonância magnética (DWI) das glândulas suprarrenais foram realizadas em aparelho de 1,5 T utilizando-se b valores de 0, 20, 500 e 1000 s/mm2. As medidas do CDA das glândulas suprarrenais foram obtidas pixel-a-pixel por dois radiologistas após co-registro automático do mapa de CDA com DWI. Resultados: A média dos valores do CDA da glândula suprarrenal direita foi 1,44 × 10-3 mm2/s no grupo PreP e 1,23 × 10-3 mm2/s no grupo PostP, e da glândula esquerda foi 1,58 × 10-3 mm2/s e 1,32 × 10-3 mm2/s, respectivamente. Os valores de CDA foram mais altos no grupo PreP comparados aos do PostP (p < 0,05). A concordância interobservador foi quase perfeita (coeficiente de correlação intraclasse: 0,84-0,94; p < 0,05). Conclusão: Estes resultados mostram que medir o CDA das glândulas suprarrenais é factível e reprodutível. Esta técnica poderia ser utilizada para medir o CDA de estruturas pequenas.

20.
Radiol. bras ; 49(6): 351-357, Nov.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-842427

RESUMO

Abstract Objective: To perform a quantitative analysis of the airways using automated software, in computed tomography images of patients with cystic fibrosis, correlating the results with spirometric findings. Materials and Methods: Thirty-four patients with cystic fibrosis were studied-20 males and 14 females; mean age 18 ± 9 years-divided into two groups according to the spirometry findings: group I (n = 21), without severe airflow obstruction (forced expiratory volume in first second [FEV1] > 50% predicted), and group II (n = 13), with severe obstruction (FEV1 ≤ 50% predicted). The following tracheobronchial tree parameters were obtained automatically: bronchial diameter, area, thickness, and wall attenuation. Results: On average, 52 bronchi per patient were studied. The number of bronchi analyzed was higher in group II. The correlation with spirometry findings, especially between the relative wall thickness of third to eighth bronchial generation and predicted FEV1, was better in group I. Conclusion: Quantitative analysis of the airways by computed tomography can be useful for assessing disease severity in cystic fibrosis patients. In patients with severe airflow obstruction, the number of bronchi studied by the method is higher, indicating more bronchiectasis. In patients without severe obstruction, the relative bronchial wall thickness showed a good correlation with the predicted FEV1.


Resumo Objetivo: Realizar a análise quantitativa das vias aéreas utilizando programa automático, em imagens de tomografia computadorizada de pacientes com fibrose cística, correlacionando com a espirometria. Materiais e Métodos: Foram estudados 34 pacientes com fibrose cística - 20 masculinos e 14 femininos; idade de 18 ± 9 anos -, divididos em dois grupos segundo a espirometria: grupo I (n = 21) - sem obstrução grave ao fluxo aéreo (volume expiratório forçado no primeiro segundo [VEF1] > 50% previsto); grupo II (n = 13) - com obstrução grave (VEF1 ≤ 50% previsto). Foram automaticamente obtidos: diâmetro, área, espessura e atenuação da parede da árvore traqueobrônquica. Resultados: Na média, foram estudados 52 brônquios por paciente. O número de brônquios analisados foi maior no grupo II. A correlação com a espirometria foi melhor no grupo I, principalmente entre a espessura relativa da parede da terceira a oitava geração brônquica e o VEF1 previsto. Conclusão: A análise quantitativa das vias aéreas em imagens de tomografia computadorizada pode ser útil na avaliação da gravidade da doença na fibrose cística. Nos pacientes com obstrução grave ao fluxo aéreo, o número de brônquios estudados pelo método é maior, indicando mais bronquiectasias. Nos pacientes sem obstrução grave, a espessura relativa da parede dos brônquios tem boa correlação com o VEF1 previsto.

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