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1.
Opt Express ; 31(11): 18063-18071, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381524

RESUMO

X-rays have developed into an essential tool in variety of fields, such as biology, materials, chemistry, and physics etc. Numerous X-ray types, including the orbital angular momentum (OAM), the Laguerre-Gauss, and the Hermite-Gauss states, have been proposed. This greatly enhances the depth of application of X-ray. The X-ray states described above are mostly produced by binary amplitude diffraction elements. In light of this, this paper proposes a flat X-ray diffraction grating based on caustic theory to generate Airy-type X-ray. It is proved by the simulation of multislice method that the proposed grating can generate the Airy beam in the X-ray field. The results show that the generated beams have a secondary parabolic trajectory deflection with the propagation distance, which is consistent with the theory. Inspired by the success of Airy beam in light-sheet microscope, the Airy-type X-ray can be anticipated to enable novel image capability for bio or nanoscience.

2.
J Ultrasound Med ; 41(3): 597-604, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33904194

RESUMO

OBJECTIVES: To analyze the imaging manifestations of common fetal oral masses by ultrasound combined with magnetic resonance imaging (MRI) and to discuss their differential diagnoses. METHODS: A retrospective study of 6 fetuses with oral masses was performed at a tertiary referral center. The imaging features of prenatal ultrasonography and MRI in the diagnosis of fetal oral masses were analyzed. RESULTS: Histopathological examination and/or postpartum ultrasound revealed lymphangioma malformation in 2 fetuses, and mucosal retention cyst, mature teratoma, immature teratoma, and cranial meningocele in 1 fetus, respectively. The teratoma had a characteristic sonographic appearance. In our study, the 4 cases of cystic masses did not have an abnormal vessel architecture. Supplemental MRI revealed a mass effect at the level of the hypopharynx, and in 2 cases with polyhydramnios, the mass obstructed the fetuses' upper airway. Thus, ex-utero intrapartum therapy surgery was performed to secure the newborn's airway. CONCLUSIONS: Oral fetal tumors represent rare congenital malformations. This study shows that a prenatal diagnosis of oral masses is feasible by ultrasound examination. MRI can further confirm the results of ultrasonography and clearly show the relationship between the mass and the hypopharynx. Ultrasonography combined with MRI could, to a large extent, facilitate early detection and appropriate treatment and improve outcome.


Assuntos
Feto , Diagnóstico Pré-Natal , Feminino , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Gravidez , Estudos Retrospectivos , Ultrassonografia , Ultrassonografia Pré-Natal
3.
Radiother Oncol ; 188: 109904, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37678624

RESUMO

BACKGROUND AND PURPOSE: Image-defined sarcopenia is linked to increased mortality among patients with cancer. Nevertheless, its effect on patients with nasopharyngeal carcinoma (NPC) is incompletely established. This study's aim was to investigate the prognostic significance of MRI-defined sarcopenia on the survival of patients undergoing concurrent chemoradiotherapy (CCRT) ± inducing chemotherapy (IC) for NPC treatment. METHODS: 1,307 patients with stage II-IVa NPC were included in this retrospective study. Sarcopenia was defined using skeletal muscle index (SMI) determined through baseline MRI at the C3 level. The association of sarcopenia with overall survival (OS) and progression-free survival (PFS) was assessed by Cox regression models using 1:1 propensity score matching (PSM) analysis. We also conducted a stratification analysis using BMI and treatment strategies. RESULTS: Sarcopenia was an independent risk factor for both OS and PFS (all P < 0.05). However, BMI was not substantially linked to OS and PFS (all P > 0.05). Sarcopenic patients showed lower rates of OS (HR = 2.00, 95% CI: 1.54-2.60, P < 0.001) and PFS (HR = 1.67, 95% CI: 1.35-2.07, P < 0.001) in contrast with nonsarcopenic patients. According to stratification analysis, being overweight was linked to a protective effect in nonsarcopenic patients only. Sarcopenic patients showed similar OS and PFS regardless of the treatment modality. CONCLUSIONS: Sarcopenia is underrecognized in NPC patients. Measurement of sarcopenia using routine MRI scans in NPC patients provided significant prognostic information, outperforming BMI. Patients with sarcopenia failed to benefit from an additional IC regimen.

4.
Front Pediatr ; 10: 968652, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389390

RESUMO

Objectives: Proximal interruption of the pulmonary artery (PIPA) has various clinical manifestations. This review focused on and summarized the clinical and radiological features of PIPA, based on relevant literature studies. Methods: The study included a total of 25 PIPA cases in the Guangzhou Women and Children's Medical Center between January 2015 and December 2021. Conventional chest photographs and chest computed tomography angiography (CCTA) of patients with PIPA were analyzed and summarized. Results: The radiological results showed that 17 cases were right-sided and 8 cases were left-sided PIPA. Additionally, the percentage of pulmonary hypoplasia on the affected side was 44%, 36% for pulmonary hypertension, 28% for the mosaic sign, 20% for subpleural cystic lucency shadow, 20% for subpleural serrated shadow, 20% for collateral vessel thickening, 16% for subpleural band-like parenchyma, 12% for pneumonia, and 56% for patent ductus arteriosus. Conclusion: The clinical manifestations of PIPA are non-specific. Awareness of this anomaly, based on radiological manifestations, particularly those observed on CCTA images, is important for ruling out alternative diagnoses and implementing appropriate management.

5.
Brain Behav ; 11(5): e02079, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33734615

RESUMO

OBJECTIVE: This study aimed to summarize the magnetic resonance imaging (MRI) and computed tomography (CT) features of the central nervous system (CNS) in children with Hoyeraal-Hreidarsson syndrome. METHODS: The imaging and clinical data of four children diagnosed with Hoyeraal-Hreidarsson syndrome by clinical and laboratory tests in the Guangzhou Women and Children's Medical Center were gathered and analyzed retrospectively. The clinical manifestations and CNS imaging features of Hoyeraal-Hreidarsson syndrome were summarized based on our results and a literature review. RESULTS: Our results showed that delayed development, skin pigmentation, nail/toenail dystrophy, thrombocytopenia, and anemia are the most observed clinical presentations of Hoyeraal-Hreidarsson syndrome. Important findings on CNS imaging showed that all patients had cerebellar hypoplasia, delayed myelination, hydrocephalus, brain atrophy, and calcification. The gene mutations in all cases were consistent with those of dyskeratosis congenita, including TINF2 mutations in three cases and DKC1 mutations in one case. CONCLUSION: Hoyeraal-Hreidarsson syndrome is a severe variant of dyskeratosis congenita. Both DKC1 and TINF2 mutations can lead to the phenotypes of Hoyeraal-Hreidarsson syndrome. In our study, CNS imaging revealed that cerebellar hypoplasia has an important diagnostic value for Hoyeraal-Hreidarsson syndrome while delayed myelination, calcification of the parenchyma, brain atrophy, and hydrocephalus are also important findings on CNS imaging. Combining imaging features with clinical and laboratory indicators can assist the diagnosis of Hoyeraal-Hreidarsson syndrome.


Assuntos
Disceratose Congênita , Encéfalo/diagnóstico por imagem , Proteínas de Ciclo Celular/genética , Criança , Feminino , Retardo do Crescimento Fetal , Humanos , Deficiência Intelectual , Microcefalia , Mutação , Neuroimagem , Proteínas Nucleares/genética , Estudos Retrospectivos
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