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- Osseodensification vs. Conventional Osteotomy: A case series with cone beam computed tomographyPublication . Costa, José Adriano; Mendes, José Manuel; Salazar, Filomena; Pacheco, José Júlio; Rompante, Paulo; Moreira, Joaquim Ferreira; Mesquita, José Diogo; Adubeiro, Nuno; Câmara, Marco Infante daOsseodensification is a non-extraction technique using specially designed drills to increase bone density while extending an osteotomy, allowing bone to be preserved and condensed by compacting autograft during osteotomy preparation, increasing bone density around implants, and improving mechanical stability. The objective of this study is to compare conventional osteotomy and osseodensification protocols in implant placement and analyze whether there are differences in bone density. Study variables were defined, namely, osseodensification technique, conventional osteotomy technique, bone density, sex, area of location, implant dimensions, implant dimensions, and implant stability. Eligibility and exclusion criteria were defined. A step-by-step surgical protocol was developed. The surgeon and radiologist underwent intra-examiner calibration. A total of 15 patients were selected according to the eligibility criteria, and a total of 41 implants were inserted, 20 implants by conventional osteotomy and 21 by osseodensification. A cone beam computed tomography was performed one year after prosthetic rehabilitation to estimate bone density. Data were collected and recorded, and in the analysis of the association of variables, non-parametric tests were applied. Significant statistical results were found in bone density values, with higher values being obtained with the osseodensification technique, that is, median density values of 1020, and median density values of 732 for the bone drilling technique. The results of the correlation between bone density in both techniques and sex, primary implant stability, implant dimensions and location area were statistically non-significant. Within the limitations of this study, there are differences in bone density between conventional osteotomy and osseodensification protocols. Bone density is increased with osseodensification over a study period of one year.
- Contributo para o estabelecimento de níveis de referência de diagnóstico em eletrofisiologia de intervenção: estudo de um centro em PortugalPublication . Videira, Sara; Pereira, José Manuel; Pereira, José ManuelA maioria dos procedimentos eletrofisiologia de intervenção necessitam de fluoroscopia expondo à radiação ionizante todos os intervenientes. O recurso a níveis de referência de diagnóstico (NRD) pode ser uma ferramenta profícua para promover a otimização de dose. O principal objetivo deste estudo consistiu em investigar as doses de exposição, determinando os NRD.
- Investigação aplicada - Aspetos globaisPublication . Aubeiro, Nuno; Adubeiro, NunoO campo da investigação na saúde é inerentemente uma área de extrema complexidade, com muitas particularidades, mas cujo aporte é fulcral para que se possam tomar decisões baseadas na evidência.
- Controlo radiográfico de dispositivos médicos em neonatologiaPublication . Reis, Raquel; Rebelo, Sofia; Pereira, José Manuel; Pereira, José ManuelA gestão clínica dos recém-nascidos nas unidades de cuidados intensivos neonatais implica a colocação de diversos dispositivos médicos invasivos que necessitam de controlo radiográfico. O principal objetivo deste trabalho consistiu em realizar uma revisão narrativa sobre as boas práticas a adotar na aquisição de imagens radiográficas, em unidades de cuidados intensivos neonatais, para o controlo de dispositivos médicos de acordo com a literatura publicada e a experiência dos autores. Realizou-se uma revisão narrativa da literatura. Recorreu-se às bases de dados científicas PubMed; Science Direct; Google Scholar e Portal RCAAP, para a recolha de documentos de análise. Foram, ainda, consultados livros das coleções particulares dos autores. A revisão narrativa incidiu sobre 39 documentos, dos quais 26 artigos científicos, quatro guidelines/consensos/recomendações e nove livros/capítulos de livro. A colocação de cateteres intravasculares, sondas nasogástricas e tubos endotraqueais são procedimentos interventivos habitualmente utilizados na prestação de cuidados a recém-nascidos prematuros internados nas unidades de cuidados intensivos neonatais. O posicionamento preciso destes dispositivos é essencial e a radiografia do tórax e abdómen desempenha um papel de extrema relevância no controlo e monitorização da colocação destes dispositivos. Os desafios técnicos inerentes à realização destes exames radiográficos assumem uma exigência suplementar atendendo aos ajustes ao posicionamento e parâmetros de exposição em relação à população adulta. Os parâmetros de aquisição, bem como o pós-processamento da imagem, deverão ser otimizados de forma a permitirem visualizar o trajeto dos dispositivos médicos em toda a sua extensão e demonstrarem inequivocamente a posição da sua extremidade distal. Ao mesmo tempo a imagem terá de apresentar leitura anatómica suficiente para a monitorização de eventuais lesões iatrogénicas. O célere reconhecimento radiográfico de dispositivos incorretamente colocados, assim como, as complicações que podem originar, é essencial para uma rápida intervenção que permita a prevenção do agravamento do estado clínico do recém-nascido.
- Análise de repetição de exames em radiologia convencionalPublication . Freitas, Artur; Pereira, José Manuel; Pereira, José ManuelA Radiologia Convencional é o método de primeira linha no diagnóstico de diversas patologias e avaliação da anatomia. A repetição de exames relaciona-se com o não cumprimento de critérios de boa realização que resultem em ausência/insuficiência de valor diagnóstico. A diminuição da taxa de repetição representa um fator importante na área da radiologia e da saúde comunitária, contribuindo para a diminuição da dose recebida pelos doentes e profissionais de saúde. O objetivo principal deste estudo foi determinar os exames de radiologia convencional mais suscetíveis de serem repetidos pelos técnicos de radiologia, e causas associadas. Realizou-se um estudo analítico, observacional e transversal. Os dados foram colhidos através da aplicação online de um inquérito por questionário aos participantes no estudo. A população em estudo consistiu em técnicos de radiologia portugueses, licenciados em radiologia ou imagem médica e radioterapia, a exercer funções em Portugal ou no estrangeiro. Para o estudo de associações entre variáveis, utilizaram-se os testes estatísticos de Correlação de Pearson e Qui-quadrado da independência. A amostra foi constituída por 228 participantes, dos quais 176 (77,2%) do sexo feminino, com média de idade de 33.93 (±10.37) anos e tempo médio de experiência profissional de 10.58 (±10.34) anos. O exame ao joelho (61%) foi considerado pelos participantes como o mais provável de ser repetido, seguido do tórax (29.4%) e ombro (24.6%). Os participantes apontaram como erro técnico mais comum o posicionamento incorreto, sendo a não colaboração do doente, o principal fator preditor de erro técnico. Observou-se uma correlação negativa de fraca amplitude entre o tempo de experiência dos profissionais e a frequência com que repetem exames radiológicos. Os exames realizados ao joelho, ombro e tórax, são aqueles que apresentam maior taxa de repetição, sendo o erro mais comum o posicionamento incorreto do doente. O fator que mais contribui para o erro é a não colaboração do doente. Os participantes realçam a necessidade do desenvolvimento de programas de formação contínua e a introdução de pequenas pausas durante os turnos.
- 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.
- Impact of walking on knee articular cartilage T2 values estimated with a dictionary-based approach - A pilot studyPublication . Coelho, José M.; Fernandes, T.T.; Alves, Sandra Maria; Nunes, R.G.; Nogueira, Luísa; Oliveira, A.Walking is crucial for knee articular cartilage (KAC) health. Routine MRI sequences lack sensitivity for early cartilage changes, and the use of parametric T2 maps to study the effect of walking on KAC composition is limited. This study aimed to evaluate if quantitative T2 maps using an Echo Modulation Curve (EMC) matching algorithm can detect KAC T2 variations due to water content changes after walking. Seven asymptomatic volunteers (3 females, 4 males, mean age 28.3 years) without knee pathologies participated. Sagittal knee MRI scans were performed before and after a 9-min treadmill walk using a Modified Bruce protocol. T2-weighted Multi-Echo Spin-Echo KAC images were acquired at 3T. Tibiofemoral cartilage was segmented semi-automatically on three slices per knee, defining 39 KAC samples. Quantitative T2 maps were created using a dictionary-matching algorithm. Paired t-tests assessed exercise impact on KAC T2 values, independent t-tests compared group differences, and Friedman test with Bonferroni correction evaluated regional T2 changes. Walking increased KAC T2 values (mean difference (md) 0.61 ± 1.71 ms; p ¼ 0.016). Significant differences were observed in “normal” BMI group (md 0.69 ± 1.27 ms; p ¼ 0.021). Regional analysis revealed significant differences in medial femur in males (md 0.9 ± 2.1 ms; p ¼ 0.049) and lateral tibia in females (md 1.4 ± 2.5 ms; p ¼ 0.046). The medial tibia showed significant differences across sub-regions (p ¼ 0.026). Quantitative T2 maps using the EMC matching algorithm detected consistent changes in KAC T2 values after a short walking period. Implications for practice: EMC quantitative T2 maps effectively detected knee cartilage changes postwalking. This technique could improve cartilage hydration assessments, aiding early detection in atrisk patients. It also suggests potential for personalized monitoring and rehabilitation, advancing musculoskeletal imaging and non-invasive joint health monitoring.
- Investigação clínica – Aspectos globaisPublication . Adubeiro, NunoO campo da investigação na saúde é inerentemente uma área de extrema compexidade, com muitas particularidades, mas cujo aporte é fulcral pra que se possam tomar decisões baseadas na evidência.
- 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.
- Editorial for “3D breast cancer segmentation in DCE‐MRI using deep learning with weak annotation”Publication . Nogueira, Luísa; Adubeiro, Nuno; Nunes, Rita G.Magnetic resonance imaging (MRI) shows higher diagnostic performance in the detection of breast tumors, compared with other imaging modalities. Breast MRI protocols include dynamic contrast-enhanced (DCE) images with high spatial and temporal resolution and are central indiagnosis, staging, and follow-up of breast cancer. DCE features provide physiological and anatomical lesion characteristics. To extract these data, manual lesion segmentation is currently performed, which is a critical time-consuming step,introducing bias and variability and impacting the reproducibility of the extracted features. To overcome these limitations, artificial intelligence algorithms have been explored, especially deep learning (DL) methods, for automatic lesion segmentation. This has been an active area of research, pivotal in the analysis of quantitative medical images. Most lesion segmentation methods have been based on semiautomatic or supervised learning approaches, presenting an important limitation: slice-by-slice 2D segmentations are typically performed, leading to suboptimal 3D masks upon concatenation. Recently, DL methods based on vision transformers have gained popularity in breast lesion segmentation, improving results over traditional machine learning. Although fully convolutional neural networks (CNNs) show powerful learning capabilities, their performance in learning long-range dependencies is limited, presenting decreased capacity in the segmentation of structures including different shapes and scales. UNETR is an architecture that replaces the CNN-based encoder with a transformer, which can capture low-level details in 3D segmentation. UNETR directly connects the encoder to the decoder via skip connections and can directly use volumetric data. Compared with CNN or transformer-based segmentation methods, UNETR can better capture dependencies at diverse spatial scales, both local and long-range enabling improved segmentation. In this retrospective study, Kim et al developed a model based on weak annotations, for detection and 3D segmentation of breast cancer in a sample of 736 women, using different input combinations in a three-time point (3TP) approach, from DCE-MRI images, acquired in two 3 T scanners from different manufacturers. The sample was divided into training (N = 544)and test sets (N = 192). To reduce the workload required toobta in ground truth segmentations, tumors were first segmented using weak annotations by two radiologists in consensus drawing bounding rectangles encompassing the lesion on two projection images. The rectangles were used to generate a 3D bounding box applied to the image obtained by subtracting the pre-contrast from the post-contrast image. An automatic thres holding method was used for automatic lesion segmentation; the mask was then refined to better define the lesion boundaries and exclude noisyor confounding regions (false positives). For training the segmen-tation network, images acquired at three different temporal acquisition points (pre-contrast, early, and delayed post-contrast) were used to construct three inputs: input 1 (pre-contrast, early phase),input 2 (pre-contrast, early, and delayed phase), and input 3 (pre-contrast and delayed phase). A different UNETR model wastrained for each input, and segmentation performances were compared, qualitatively and quantitatively, based on MRI features and immunohistochemical (IHC) classification. The best DL model presented a reliable performance for automated 3D segmentation of breast cancer with a median dicesimilarity coefficient (DSC) of 0.75 for the whole breast and 0.89 for the index lesion. The performance of the UNETR model was in accordance with the DSC values reported by other researchers employing alternative segmentation algorithms. Regarding the qualitative analysis of the segmentation results, the segmentation was successfully done in 83% of the cases derived from inputs 1 and 2, and from these, 95% were considered as acceptable detection. The authors also evaluated the performance of the segmentation according to base line characteristics and found significant differences for the whole breast and main lesion. For main lesion, significant differences were observed according to lesion size and IHC type. Regarding visual analysis, significant differences were found between lesion type (mass vs. non-mass enhancement) and background parenchymal enhancement (BPE) level. In their study, there were nine cases of failed segmentation, which corresponded totumors with small volumes, from which five cases were not segmented and four cases corresponded to abundant BPE,meaning false-positive results.© 2023 International Society for Magnetic Resonance in Medicine. 2263 Further developments of 3D UNETR architecture could be done to improve small lesion detection, to distinguish between mass and non-mass lesions, especially the boundaries of non-masses, and to distinguish between BPE and tumors. Attending to the implementation of DL algorithms in the clinical practice, this type of algorithm is expected to improve the detection of small lesions and the prediction of response to treatment, there by reducing the number of performed biopsies and, potentially, enabling the use of an abbreviated MRI pro-tocol, which would reduce MRI exam durations, improving patient comfort, and reducing costs.