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1.
Insights Imaging ; 14(1): 1, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36600120

RESUMO

BACKGROUND: High-intensity focused ultrasound (HIFU) is used for the treatment of symptomatic leiomyomas. We aim to automate uterine volumetry for tracking changes after therapy with a 3D deep learning approach. METHODS: A 3D nnU-Net model in the default setting and in a modified version including convolutional block attention modules (CBAMs) was developed on 3D T2-weighted MRI scans. Uterine segmentation was performed in 44 patients with routine pelvic MRI (standard group) and 56 patients with uterine fibroids undergoing ultrasound-guided HIFU therapy (HIFU group). Here, preHIFU scans (n = 56), postHIFU imaging maximum one day after HIFU (n = 54), and the last available follow-up examination (n = 53, days after HIFU: 420 ± 377) were included. The training was performed on 80% of the data with fivefold cross-validation. The remaining data were used as a hold-out test set. Ground truth was generated by a board-certified radiologist and a radiology resident. For the assessment of inter-reader agreement, all preHIFU examinations were segmented independently by both. RESULTS: High segmentation performance was already observed for the default 3D nnU-Net (mean Dice score = 0.95 ± 0.05) on the validation sets. Since the CBAM nnU-Net showed no significant benefit, the less complex default model was applied to the hold-out test set, which resulted in accurate uterus segmentation (Dice scores: standard group 0.92 ± 0.07; HIFU group 0.96 ± 0.02), which was comparable to the agreement between the two readers. CONCLUSIONS: This study presents a method for automatic uterus segmentation which allows a fast and consistent assessment of uterine volume. Therefore, this method could be used in the clinical setting for objective assessment of therapeutic response to HIFU therapy.

2.
Eur Radiol Exp ; 6(1): 48, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36171532

RESUMO

BACKGROUND: To evaluate simplified intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) for differentiating malignant versus benign breast lesions as (i) stand-alone tool and (ii) add-on to dynamic contrast-enhanced magnetic resonance imaging. METHODS: 1.5-T DWI data (b = 0, 50, 250, 800 s/mm2) were retrospectively analysed for 126 patients with malignant or benign breast lesions. Apparent diffusion coefficient (ADC) ADC (0, 800) and IVIM-based parameters D1' = ADC (50, 800), D2' = ADC (250, 800), f1' = f (0, 50, 800), f2' = f (0, 250, 800) and D*' = D* (0, 50, 250, 800) were voxel-wise calculated without fitting procedures. Regions of interest were analysed in vital tumour and perfusion hot spots. Beside the single parameters, the combined use of D1' with f1' and D2' with f2' was evaluated. Lesion differentiation was investigated for lesions (i) with hyperintensity on DWI with b = 800 s/mm2 (n = 191) and (ii) with suspicious contrast-enhancement (n = 135). RESULTS: All lesions with suspicious contrast-enhancement appeared also hyperintense on DWI with b = 800 s/mm2. For task (i), best discrimination was reached for the combination of D1' and f1' using perfusion hot spot regions-of-interest (accuracy 93.7%), which was higher than that of ADC (86.9%, p = 0.003) and single IVIM parameters D1' (88.0%) and f1' (87.4%). For task (ii), best discrimination was reached for single parameter D1' using perfusion hot spot regions-of-interest (92.6%), which were slightly but not significantly better than that of ADC (91.1%) and D2' (88.1%). Adding f1' to D1' did not improve discrimination. CONCLUSIONS: IVIM analysis yielded a higher accuracy than ADC. If stand-alone DWI is used, perfusion analysis is of special relevance.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Movimento (Física) , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Int J Hyperthermia ; 38(2): 65-74, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34420445

RESUMO

INTRODUCTION: High-intensity focused ultrasound (HIFU) is an innovative noninvasive procedure for local ablation of different benign and malignant tumors. Preliminary data of animal studies suggest an ablation-associated immune response after HIFU that is induced by cell necrosis and release of intracellular components. The aim of this study is to evaluate if a HIFU-induced early sterile inflammatory reaction is initiated after ablation of uterine fibroids (UF) and pancreatic carcinoma (PaC) which might contribute to the therapeutic effect. MATERIAL AND METHODS: A hundred patients with PaC and 30 patients with UF underwent US-guided HIFU treatment. Serum markers of inflammation (leukocytes, CRP, IL-6) and LDH in both collectives as well as tumor markers CA 19-9, CEA and CYFRA in PaC patients were determined in sub-cohorts before and directly after HIFU (0, 2, 5 and 20 h post-ablation) as well as at 3, 6, 9 and 12 months follow-up. Peri-/post interventional imaging included contrast-enhanced MRI of both cohorts and an additional CT scan of PaC patients. RESULTS: An early post-ablation inflammatory response was observed in both groups with a significant increase of leukocytes, CRP and LDH within the first 20 h after HIFU. Interestingly, IL-6 was increased at 20 h after HIFU in PaC patients. A significant reduction of tumor volumes was observed during one year follow-up (p < .001) for both tumor entities demonstrating effective treatment outcome. CONCLUSION: Tumor ablation with HIFU induces an early sterile inflammation that might serve as a precondition for long-term tumor immunity and a sustainable therapeutic effect.


Assuntos
Neoplasias Abdominais , Ablação por Ultrassom Focalizado de Alta Intensidade , Neoplasias Uterinas , Feminino , Alemanha , Humanos , Inflamação/diagnóstico por imagem , Laboratórios , Resultado do Tratamento
4.
Int J Hyperthermia ; 38(2): 30-38, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34420447

RESUMO

INTRODUCTION: To evaluate treatment response of uterine fibroids after ultrasound guided high-intensity focused ultrasound (USgHIFU) with a special focus on fibroid size and characterization based on Funaki classification scheme, as well as clinical response to treatment of leading fibroid-associated symptoms. MATERIALS AND METHODS: Uterine fibroids treated by USgHIFU were assigned to Funaki type 1-3 based on T2-w-MRI. Differences in size, non-perfused volume ratio (NPVR) and volume reduction over time were determined using T1-/T2-w MRI sequences and contrast-enhanced sonography. Treatment effects on three leading fibroid-associated symptoms were also evaluated. Measurements were compared by mixed model, Bland-Altman's plot and Spearman's correlation. RESULTS: In this prospective single-center study, 35 patients with 44 symptomatic uterine fibroids were treated by USgHIFU (n = 22, n = 12 and n = 10 assigned to Funaki type 1, 2 and 3, respectively). NPVRs of Funaki type 1 and 2 fibroids were significantly higher compared to type 3 (p = .0023). A significant fibroid shrinkage was observed independent of Funaki type compared to baseline: 38.8 ± 26.9%, 46.7 ± 30.3% and 54.5 ± 29.3% at 3, 6 and 12 months, respectively (each p < .05). Moreover, patients experienced a significant improvement of fibroid-associated hypermenorrhea (3.9 ± 1.3 vs. 2.3 ± 1.3), pressure in the pelvic area (3.5 ± 1.3 vs. 2.1 ± 0.9) and frequent urination (2.8 ± 1.5 vs. 1.9 ± 0.8) one year post-procedure (each p < .05), regardless of fibroid Funaki type. CONCLUSION: Following USgHIFU, a significant shrinkage of uterine fibroids and improvement of leading fibroid-associated symptoms were demonstrated regardless of the Funaki type.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma , Neoplasias Uterinas , Feminino , Humanos , Leiomioma/diagnóstico por imagem , Leiomioma/cirurgia , Imageamento por Ressonância Magnética , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/cirurgia
5.
NPJ Genom Med ; 6(1): 55, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210994

RESUMO

Among children, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections are typically mild. Here, we describe the case of a 3.5-year-old girl with an unusually severe presentation of coronavirus disease (COVID-19). The child had an autoinflammatory disorder of unknown etiology, which had been treated using prednisolone and methotrexate, and her parents were half cousins of Turkish descent. After 5 days of nonspecific viral infection symptoms, tonic-clonic seizures occurred followed by acute cardiac insufficiency, multi-organ insufficiency, and ultimate death. Trio exome sequencing identified a homozygous splice-variant in the gene TBK1, and a homozygous missense variant in the gene TNFRSF13B. Heterozygous deleterious variants in the TBK1 gene have been associated with severe COVID-19, and the variant in the TNFRSF13B gene has been associated with common variable immunodeficiency (CVID). We suggest that the identified variants, the autoinflammatory disorder and its treatment, or a combination of these factors probably predisposed to lethal COVID-19 in the present case.

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