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- Diffusion MRI outside the brainPublication . Nunes, Rita G.; Nogueira, Luisa; Gaspar, Andreia S.; Adubeiro, Nuno; Brandão, SofiaThis manuscript provides an overview of recent developments in Diffusion-Weighted Imaging (DWI) outside the brain, focusing on liver, breast, prostate, muskuloskeletal (MSK) and cardiac applications. A general introduction to cross-cutting acquisition and image processing challenges is first provided. These often include short T2 relaxation times, the need to image a large field-of-view with the resulting complications in shimming the B0 field and achieving good fat suppression. Some of the strategies developed for dealing with motion, namely cardiac and respiratory motion are described. Specific sections are then presented for each of the aforementioned organs. A motivation for the clinical applicability of DWI is first provided, followed by specific image acquisition and processing considerations. Quantitative imaging is becoming standard in clinical practice, and the Apparent Diffusion Coefficient is routinely estimated in the liver, breast and prostate. Application of alternative signal models in these organs is being explored, including both the Intravoxel Incoherent Motion and Diffusion Kurtosis models. Ongoing efforts are focused on evaluating the potential clinical added value of the extra parameters and on improving their repeatability. MSK and cardiac DWI have shown potential for assessing pathological changes in fiber architecture, but further validation is required to enable application in the clinical setting.
- Editorial for “Three‐dimensional multifrequency MR elastography for microvascular invasion and prognosis assessment in Hepatocellular Carcinoma”Publication . Adubeiro, Nuno; Nunes, Rita G.; Nogueira, LuísaThe prognosis of individuals with hepatocellular carcinoma(HCC), the most prevalent primary liver malignancy, is closely linked to the aggressiveness and recurrence of the tumor. The occurrence of complications after surgery continues to be a major and persistent challenge. MR elastography (MRE) employs a modified phase-contrast imaging sequence, combined with the use of an external driver to transmit mechanical vibrations to the tissues, to identify propagating shear waves within the liver. This technique allows the assessment of a substantial portion of the liver and provides information on multiple mechanical properties associated with various pathophysiological states. Due to substantial progress in MR technology, MRE has proven to be a precise noninvasive diagnostic method for detecting and monitoring various liver diseases. MRE imaging could serve as a valuable tool for staging malignancy and predict disease prognosis.
- Influence of the minimum b-value on prostate cancer assessment using conventional DWI and DKI modelsPublication . Adubeiro, N.; Nogueira, L.; Nunes, R. G.; Ferreira, H. A.; Ribeiro, E. F. C.; Fuente, J. M. LaTo investigate the influence of the minimum b-value in diffusion parameters estimated for prostate tissues using mono-exponential and kurtosis models.
- Apparent diffusion coefficient in the analysis of prostate cancerPublication . Adubeiro, Nuno; Nogueira, Luísa; Ribeiro, Eduardo; Alves, Sandra; Ferreira, Hugo; La Fuente, JoséThe multiparametric magnetic resonance imaging (MPMRI) approach, has allowed the diagnostic performance in the detection and characterization of prostate cancer (PCa). Diffusion-weighted imaging (DWI), is an important technique in the MPMRI, that provides qualitative and quantitative biological information regarding water diffusivity in a non-invasive manner. The apparent diffusion coefficient (ADC) measures water mobility and can be quantified from the signal intensity loss between two or more b-values. Different studies reported that ADC values are directly associated with microvessel density and cellularity. One of the main aspects that is in discussion is the b-values that must be used in the DWI sequence in order to compute ADC.
- Body mass index and visceral fat: correlation with serum lipid profile in healthy young adultsPublication . Moreira, Anabela; Noites, Andreia; Couto, Miriam; Vilarinho, Rui; Melo, Cristina; Sousa, Manuela; Monteiro, Pedro; Carvalho, Paulo; Adubeiro, Nuno; Nogueira, Luisa; Santos, RubimMetabolic and cardiovascular complications and obesity association is well described. Body mass index (BMI) is commonly used to assess obesity, but does not reflect body fat distribution. Abdominal obesity, namely visceral adipose tissue (VAT), is associated with greater risk for those metabolic impairments, including dyslipidemia, than adiposity in other regions of the body. Objective: To determine the correlation between serum lipid profile and anthropometric measures (BMI and VAT) in young healthy adults.
- Genetic variation in Wnt/β-catenin and ER signalling pathways in female and male elite dancers and its associations with low bone mineral density: a cross-section and longitudinal studyPublication . Amorim, T.; Durães, C.; Machado, J. C.; Metsios, G. S.; Wyon, M.; Maia, J.; Flouris, A. D.; Marques, F.; Nogueira, Luisa; Adubeiro, Nuno; Koutedakis, Y.The association of genetic polymorphisms with low bone mineral density in elite athletes have not been considered previously. The present study found that bone mass phenotypes in elite and pre-elite dancers are related to genetic variants at the Wnt/β-catenin and ER pathways.
- Diffusion-weighted breast imaging at 3 T: Preliminary experiencePublication . Nogueira, Luisa; Brandão, S.; Matos, E.; Nunes, R. G.; Ferreira, H. A.; Loureiro, J.; Ramos, I.To evaluate the performance of diffusion-weighted imaging (DWI) at 3 T for the detection and characterization of breast lesions.
- Efeito e fatores preditivos da variação do glicerol sanguíneo induzido por eletrolipólise associada a exercício físico moderadoPublication . Couto, M; Noites, Andreia; Vilarinho, Rui; Melo, Cristina; Monteiro, Pedro; Moreira, A.; Cerqueira, Maria Manuela Amorim; Costa, D.; Adubeiro, Nuno; Nogueira, Luisa; Santos, RubimA acumulação de triglicerídeos no tecido adiposo abdominal acarreta risco acrescido para a saúde. Existem poucos estudos que demonstrem o efeito da eletrolipólise sobre o adipócito. A eletrolipólise poderá ser uma medida terapêutica coadjuvante ao exercício com o objectivo de potenciar a lipólise localizada. Assim torna-se pertinente reproduzir tais estudos, explorando se existem características individuais preditivas de mobilização lipolítica
- Editorial for “Detecting adverse pathology of prostate cancer with a deep learning approach based on a 3D swin-transformer model and biparametric MRI: A multicenter retrospective study"Publication . Adubeiro, Nuno; Nogueira, LuísaProstate cancer (PCa) is the second most prevalent cancer among men worldwide. Timely and accurate diagnosis is important to avoid overtreatment of men with indolent, clinically insignificant PCa and to offer radical curative treatment with life-threatening, clinically significant PCa. Radical prostatectomy (RP) has become the standard care for eligible patients because of its cancer control and improved survival. Although most patients remained disease-free after RP, 20%–30% of patients develop recurrence of the disease at follow-up.3 Therefore, the assessment of reliable prognostic predictors of recurrence after RP is clinically important for guiding clinical decision-making and patient counseling. To date, several factors are considered adverse pathology (AP) features such as preoperative prostate-specific antigen (PSA) levels, Gleason score, tumor stage, surgical margin status, lymph node invasion, extracapsular extension (ECE), and seminal vesicle invasion (SVI). All of them have been identified as prognostic factors for recurrence after RP.
- Genetic variants at the Wnt/[beta]-catenin and oestrogen receptor signalling pathways are associated with low bone mineral density in dancersPublication . Amorim, Tânia; Durães, Cecília; Maia, José; Machado, José Carlos; Nogueira, Luísa; Adubeiro, Nuno; Flouris, Andreas D.; Metsios, George S.; Marques, Franklim; Wyon, Matthew; Koutedakis, YiannisResearch suggests that dancers are at higher risk of developing low bone mineral density (BMD) compared with the general population. However, the associated factors contributing to low BMD in dancers are not fully understood. We aimed to assess the association of single-nucleotide polymorphisms (SNPs) in the Wnt/b-catenin and oestrogen receptor (ER) signalling pathways with low BMD in dancers.