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1.
Int J Comput Assist Radiol Surg ; 18(2): 401-408, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36198997

RESUMO

PURPOSE: Overageing and climate change cause a need for making processes in the operating room wing (OR wing) more efficient. While many promising technologies are available today, traditional OR wings are not designed for seamlessly integrating these aids. To overcome this discrepancy, we present and motivate multiple ideas on how to transform current architectural design strategies. METHODS: The presented concepts originate from expert discussions and studies of the available literature, but also from experiences made in the course of daily care delivery. Additionally, a comprehensive evaluation of current and historic OR theatre designs and the problems which are encountered herein has been conducted. RESULTS: We present three innovative concepts regarding the restructuring of traditional OR wing layouts. To achieve better process optimization, hygiene, and energy efficiency, we propose to divide the OR wing into separate "patient", "procedure" and "staff" zones. For better flexibility regarding perioperative needs and technology integration, we propose to use a hexagon shape combined with reconfigurable walls for designing operating rooms. CONCLUSION: The concepts presented herein provide a solid foundation for further considerations regarding perioperative process optimization and seamless integration of technology into modern OR wing facilities. We aim at expanding on these results to develop a comprehensive vision for the OR wing of the future.


Assuntos
Salas Cirúrgicas , Tecnologia , Humanos
2.
Int J Comput Assist Radiol Surg ; 17(6): 1177-1187, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34910277

RESUMO

PURPOSE: Today's hospitals are designed as collections of individual departments, with limited communication and collaboration between medical sub-specialties. Patients are constantly being moved between different places, which is detrimental for patient experience, overall efficiency and capacity. Instead, we argue that care should be brought to the patient, not vice versa, and thus propose a novel hospital architecture concept that we refer to as Patient Hub. It envisions a truly patient-centered, department-less facility, in which all critical functions occur in the same building and on the same floor. METHODS: To demonstrate the feasibility and benefits of our concept, we selected an exemplary patient scenario and used 3D software to simulate resulting workflows for both the Patient Hub and a traditional hospital based on a generic hospital template by Kaiser-Permanente. RESULTS: According to our workflow simulations, the Patient Hub model effectively eliminates waiting and transfer times, drastically simplifies wayfinding, reduces overall traveling distances by 54%, reduces elevator runs by 78% and improves access to quality views from 67 to 100% for patient rooms, from 0 to 100% for exam rooms and from 0 to 38% for corridors. In addition, the interaction of related medical fields is improved while maintaining the quality of care and the relationship between patients and caregivers. CONCLUSION: With the Patient Hub concept, we aim at rethinking traditional hospital layouts. We were able to demonstrate, alas on a proof-of-concept basis, that it is indeed feasible to place the patient at the very center of operations, while increasing overall efficiency and capacity at the same time and maintaining the quality of care.


Assuntos
Hospitais , Assistência Centrada no Paciente , Humanos
3.
Int J Comput Assist Radiol Surg ; 15(10): 1639-1643, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32361856

RESUMO

PURPOSE: The MEDIRAD project is about the effects of low radiation dose in the context of medical procedures. The goal of the work is to develop an informatics service that will provide the researchers of the MEDIRAD project with a platform to share acquired images, along with the associated dosimetric data pertaining to the radiation resulting from the procedure. METHODS: The authors designed a system architecture to manage image data and dosimetric data in an integrated way. DICOM and non-DICOM data are stored in separated repositories, and the link between the two is provided through a semantic database, i.e., a database whose information schema in aligned with an ontology. RESULTS: The system currently supports CT, PET, SPECT, and NM images as well as dose reports. Currently, two workflows for non-DICOM data generated from dosimetric calculations have been taken into account, one concerning Monte Carlo-based calculation of organ doses in Chest CT, and the other estimation of doses in nontarget organs in 131I targeted radionuclide therapy of the thyroid. CONCLUSION: The system is currently deployed, thus providing access to image and related dosimetric data to all MEDIRAD users. The software was designed in such a way that it can be reused to support similar needs in other projects.


Assuntos
Bases de Dados Factuais , Disseminação de Informação , Radiometria , Tomografia Computadorizada por Raios X/métodos , Humanos , Método de Monte Carlo , Software
4.
Neuroimage ; 214: 116729, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32165264

RESUMO

Nicotinic acetylcholine receptors (nAChRs) are widely distributed in the human brain and play an important role in the neuromodulation of brain networks implicated in attentional processes. Previous work in humans showed that heteromeric α4ß2 nAChRs are abundant in the cingulo-insular network underlying attentional control. It has been proposed that cholinergic neuromodulation by α4ß2 nAChRs is involved in attentional control during demanding tasks, when additional resources are needed to minimize interference from task-irrelevant stimuli and focus on task-relevant stimuli. Here we investigate the link between the availability of α4ß2 nAChRs in the cingulo-insular network and behavioral measures of interference control using two versions of the Stroop paradigm, a task known to recruit cingulo-insular areas. We used a previously published PET dataset acquired in 24 non-smoking male subjects in the context of a larger study which investigated the brain distribution of nAChRs in two clinical groups using 2-[(18)F]F-A-85380 PET. We found that higher availability of α4ß2 nAChRs in the dorsal anterior cingulate cortex (ACC) predicted better interference control independently of group and age. In line with animal models, our results support the view that the availability of α4ß2 nAChRs in the dorsal ACC is linked with more efficient attentional control.


Assuntos
Atenção/fisiologia , Giro do Cíngulo/metabolismo , Receptores Nicotínicos/metabolismo , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Teste de Stroop , Adulto Jovem
5.
Eur Radiol Exp ; 4(1): 11, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034573

RESUMO

Radiomics, artificial intelligence, and deep learning figure amongst recent buzzwords in current medical imaging research and technological development. Analysis of medical big data in assessment and follow-up of personalised treatments has also become a major research topic in the area of precision medicine. In this review, current research trends in radiomics are analysed, from handcrafted radiomics feature extraction and statistical analysis to deep learning. Radiomics algorithms now include genomics and immunomics data to improve patient stratification and prediction of treatment response. Several applications have already shown conclusive results demonstrating the potential of including other "omics" data to existing imaging features. We also discuss further challenges of data harmonisation and management infrastructure to shed a light on the much-needed integration of radiomics and all other "omics" into clinical workflows. In particular, we point to the emerging paradigm shift in the implementation of big data infrastructures to facilitate databanks growth, data extraction and the development of expert software tools. Secured access, sharing, and integration of all health data, called "holomics", will accelerate the revolution of personalised medicine and oncology as well as expand the role of imaging specialists.


Assuntos
Algoritmos , Diagnóstico por Imagem , Oncologia , Medicina de Precisão/métodos , Humanos
6.
AMIA Annu Symp Proc ; 2020: 492-501, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33936422

RESUMO

Medical ionizing radiation procedures and especially medical imaging are a non negligible source of exposure to patients. Whereas the biological effects of high absorbed doses are relatively well known, the effects of low absorbed doses are still debated. This work presents the development of a computer platform called Image and Radiation Dose BioBank (IRDBB) to manage research data produced in the context of the MEDIRAD project, a European project focusing on research on low doses in the context of medical procedures. More precisely, the paper describes a semantic database linking dosimetric data (such as absorbed doses to organs) to the images corresponding to X-rays exposure (such as CT images) or scintigraphic images (such as SPECT or PET images) that allow measuring the distribution of a radiopharmaceutical. The main contributions of this work are: 1) the implementation of the semantic database of the IRDBB system and 2) an ontology called OntoMEDIRAD covering the domain of discourse involved in MEDIRAD research data, especially many concepts from the DICOM standard modelled according to a realist approach.


Assuntos
Mineração de Dados/métodos , Diagnóstico por Imagem , Documentação/métodos , Processamento de Linguagem Natural , Radiometria , Semântica , Algoritmos , Sistemas de Gerenciamento de Base de Dados , Bases de Dados Factuais , Humanos , Aprendizado de Máquina , Doses de Radiação , Radiografia , Radiometria/métodos , Terminologia como Assunto
7.
Mol Imaging Biol ; 22(2): 417-424, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31140109

RESUMO

PURPOSE: The parcellation of the thalamus into different nuclei involved in different corticothalamocortical loops reflects its functional diversity. The connections between the mediodorsal nucleus and the prefrontal cortex play a major role in cognition, particularly in the rapid processing of behaviorally relevant information. The thalamus is the brain region with the highest density in α4ß2 nicotinic acetylcholine receptors, the main human nicotinic acetylcholine receptor subtype. The aim of this study was to investigate the possible role of the nicotinic cholinergic system in the thalamo-cortical loops measuring receptor density in different subregions of the thalamus, based on their cortical connectivity. PROCEDURES: We studied α4ß2 nicotinic acetylcholine receptors using positron emission tomography and [18F]Fluoro-A-85380, a radiotracer specific for this receptor subtype, in 36 non-smoking male subjects, including 12 healthy controls and 24 patients with epilepsy. [18F]Fluoro-A-85380 ratio index of binding potential was compared by a repeated measures general linear model, including the thalamic subregions and the brain hemisphere as within-subject factor and clinical groups as between-subject factor. RESULTS: The "prefrontal" thalamus, the subregion including the mediodorsal nucleus, had a significantly higher nicotinic acetylcholine receptor density than all other thalamic subregions. These findings were confirmed when analyzing solely the 12 healthy controls. CONCLUSIONS: This particular neurochemical organization of the thalamus supports a major role of the cholinergic system in the loops between the thalamus and the prefrontal cortex. The highest nicotinic acetylcholine receptor density in the « higher-order thalamus ¼ could partly explain the beneficial effect of acute nicotine on attentional and executive functions and possibly the pathophysiology of some neuropsychiatric disorders.


Assuntos
Epilepsia/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Receptores Nicotínicos/metabolismo , Tálamo/diagnóstico por imagem , Adulto , Mapeamento Encefálico , Cognição , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Receptores Nicotínicos/química
8.
Med Oncol ; 36(8): 67, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31190232

RESUMO

To evaluate the diagnostic performance of a whole-body 18F-choline (FCH) hybrid PET/MRI for prostate cancer patients at biochemical relapse after radical prostatectomy (RP) compared to pelvic multiparametric MRI (mpMRI), one of the standard imaging modality for this patient population. From 2010 to 2016, 58 whole-body FCH PET/MRI studies with mpMRI acquisitions were performed in 53 prostate cancer patients relapsing after curative RP. Median PSA and PSA doubling time (PSA DT) at PET study were 1.5 ng/ml and 6.5 months, respectively. The overall positivity rate of FCH PET/MRI was 58.6% (n = 34), dropping to 44% in patients with a PSA ≤ 2 ng/ml (n = 36). Median PSA values in positive and negative PET/MRI studies were 2.2 ng/ml and 0.8 ng/ml, respectively, with no differences in PSA DT (6.5 vs. 6.6 months). A PSA value ≥ 1.5 ng/ml was a significant predictor of positivity on PET/MRI studies. Compared to PET, mpMRI identified more local relapses (17 vs. 14, p = 0.453) while PET outperformed whole-body Dixon MRI for regional (16 vs. 9, p = 0.016) and distant (12 vs. 6, p = 0.031) metastases. Compared to pelvic mpMRI, the treatment approach turned out to be influenced more frequently using whole-body FCH hybrid PET/MRI studies (58.6% vs. 38%). In prostate cancer patients with biochemical recurrence after RP, whole-body FCH PET/MRI achieved a higher detection rate of nodal/distant metastases compared to pelvic mpMRI alone, increasing the change of treatment strategy by more than 20%.


Assuntos
Recidiva Local de Neoplasia/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Colina/análogos & derivados , Radioisótopos de Flúor , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Prospectivos , Prostatectomia , Neoplasias da Próstata/cirurgia , Compostos Radiofarmacêuticos , Imagem Corporal Total/métodos
9.
Eur Radiol ; 28(2): 651-663, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28812148

RESUMO

PURPOSE: To determine the diagnostic performance of FDG-PET/MRI with diffusion-weighted imaging (FDG-PET/DWIMRI) for detection and local staging of head and neck squamous cell carcinoma (HNSCC) after radio(chemo)therapy. MATERIALS AND METHODS: This was a prospective study that included 74 consecutive patients with previous radio(chemo)therapy for HNSCC and in whom tumour recurrence or radiation-induced complications were suspected clinically. The patients underwent hybrid PET/MRI examinations with morphological MRI, DWI and FDG-PET. Experienced readers blinded to clinical/histopathological data evaluated images according to established diagnostic criteria taking into account the complementarity of multiparametric information. The standard of reference was histopathology with whole-organ sections and follow-up ≥24 months. Statistical analysis considered data clustering. RESULTS: The proof of diagnosis was histology in 46/74 (62.2%) patients and follow-up (mean ± SD = 34 ± 8 months) in 28/74 (37.8%). Thirty-eight patients had 43 HNSCCs and 46 patients (10 with and 36 without tumours) had 62 benign lesions/complications. Sensitivity, specificity, and positive and negative predictive value of PET/DWIMRI were 97.4%, 91.7%, 92.5% and 97.1% per patient, and 93.0%, 93.5%, 90.9%, and 95.1% per lesion, respectively. Agreement between imaging-based and pathological T-stage was excellent (kappa = 0.84, p < 0.001). CONCLUSION: FDG-PET/DWIMRI yields excellent results for detection and T-classification of HNSCC after radio(chemo)therapy. KEY POINTS: • FDG-PET/DWIMRI yields excellent results for the detection of post-radio(chemo)therapy HNSCC recurrence. • Prospective one-centre study showed excellent agreement between imaging-based and pathological T-stage. • 97.5% of positive concordant MRI, DWI and FDG-PET results correspond to recurrence. • 87% of discordant MRI, DWI and FDG-PET results correspond to benign lesions. • Multiparametric FDG-PET/DWIMRI facilitates planning of salvage surgery in the irradiated neck.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Fluordesoxiglucose F18/farmacologia , Neoplasias de Cabeça e Pescoço/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Adulto , Idoso , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , Feminino , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Compostos Radiofarmacêuticos/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço
10.
Q J Nucl Med Mol Imaging ; 62(2): 200-208, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25319041

RESUMO

BACKGROUND: We sought to evaluate the potential role of positron emission tomography-computed tomography (PET-CT) for the detection and diagnosis of potential infections of vascular grafts using combining metabolic (i.e., radioactive fluorine-fluoro-D-deoxyglucose [18F-FDG]) PET with morphological (CT) information and investigate long-term capability. METHODS: Seventeen patients with suspected vascular-graft infection underwent thoracic-abdominal-pelvic FDG PET combined with contrast-enhanced CT using a hybrid PET-CT scanner providing co-registered PET and CT images. RESULTS: In this retrospect study, we suspected graft infection in 14 of 17 patients detected using PET-CT and increased the maximal uptake of 18F-FDG around the grafts. Other vascular localizations were not observed. All patients with positive PET-CT results underwent redo-surgery, and the infection was ultimately confirmed using microbiological testing in 12 of 14 patients. Follow-up time was median of 58 months (range 36-73 months) for all 17 patients. In these patients, there was no further evidence of graft infection found on clinical and imaging follow-up. CONCLUSIONS: This is first investigation presenting long-term follow-up, which confirmed that 18F-FDG-PET/CT is an excellent diagnostic modality for suspected vascular graft infection. 18F-FDG PET-CT exhibited a sensitivity of 100% and specificity of 71.4% for the detection of vascular-graft infection.


Assuntos
Prótese Vascular/microbiologia , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Infecções Relacionadas à Prótese/diagnóstico por imagem , Compostos Radiofarmacêuticos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
11.
Biomed Res Int ; 2017: 7039406, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28812019

RESUMO

PURPOSE: The use of SPECT/CT in bone scans has been widespread in recent years, but there are no specific guidelines concerning the optimal acquisition protocol. Two strategies have been proposed: targeted SPECT/CT for equivocal lesions detected on planar images or systematic whole-body SPECT/CT. Our aim was to compare the diagnostic accuracy of the two approaches. METHODS: 212 consecutive patients with a history of cancer were referred for bone scans to detect bone metastases. Two experienced readers randomly evaluated for each patient either planar images with one-field SPECT/CT targeted on equivocal focal uptakes (targeted SPECT/CT) or a whole-body (two-field) SPECT/CT acquisition from the base of the skull to the proximal femurs (whole-body SPECT/CT). The exams were categorized as "nonmetastatic," "equivocal," or "metastatic" on both protocols. The presence or absence of any extra-axial skeletal lesions was also assessed. The sensitivity and specificity of both strategies were measured using the results of subsequent imaging follow-up as the reference standard. RESULTS: Whole-body SPECT/CT had a significantly higher sensitivity than targeted SPECT/CT to detect bone metastases (p = 0.0297) and to detect extra-axial metastases (p = 0.0266). There was no significant difference in specificity among the two approaches. CONCLUSION: Whole-body SPECT/CT is the optimal modality of choice for metastatic workup, including detection of extra-axial lesions, with improved sensitivity and similar specificity compared to targeted SPECT/CT.


Assuntos
Neoplasias Ósseas/diagnóstico , Neoplasias/diagnóstico , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Neoplasias Ósseas/secundário , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Compostos Radiofarmacêuticos/uso terapêutico
12.
Lancet Neurol ; 16(8): 661-676, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28721928

RESUMO

The diagnosis of Alzheimer's disease can be improved by the use of biological measures. Biomarkers of functional impairment, neuronal loss, and protein deposition that can be assessed by neuroimaging (ie, MRI and PET) or CSF analysis are increasingly being used to diagnose Alzheimer's disease in research studies and specialist clinical settings. However, the validation of the clinical usefulness of these biomarkers is incomplete, and that is hampering reimbursement for these tests by health insurance providers, their widespread clinical implementation, and improvements in quality of health care. We have developed a strategic five-phase roadmap to foster the clinical validation of biomarkers in Alzheimer's disease, adapted from the approach for cancer biomarkers. Sufficient evidence of analytical validity (phase 1 of a structured framework adapted from oncology) is available for all biomarkers, but their clinical validity (phases 2 and 3) and clinical utility (phases 4 and 5) are incomplete. To complete these phases, research priorities include the standardisation of the readout of these assays and thresholds for normality, the evaluation of their performance in detecting early disease, the development of diagnostic algorithms comprising combinations of biomarkers, and the development of clinical guidelines for the use of biomarkers in qualified memory clinics.


Assuntos
Doença de Alzheimer/diagnóstico , Biomarcadores , Diagnóstico Precoce , Estudos de Validação como Assunto , Humanos
13.
Neurobiol Aging ; 52: 183-195, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28317648

RESUMO

The use of Alzheimer's disease (AD) biomarkers is supported in diagnostic criteria, but their maturity for clinical routine is still debated. Here, we evaluate brain fluorodeoxyglucose positron emission tomography (FDG PET), a measure of cerebral glucose metabolism, as a biomarker to identify clinical and prodromal AD according to the framework suggested for biomarkers in oncology, using homogenous criteria with other biomarkers addressed in parallel reviews. FDG PET has fully achieved phase 1 (rational for use) and most of phase 2 (ability to discriminate AD subjects from healthy controls or other forms of dementia) aims. Phase 3 aims (early detection ability) are partly achieved. Phase 4 studies (routine use in prodromal patients) are ongoing, and only preliminary results can be extrapolated from retrospective observations. Phase 5 studies (quantify impact and costs) have not been performed. The results of this study show that specific efforts are needed to complete phase 3 evidence, in particular comparing and combining FDG PET with other biomarkers, and to properly design phase 4 prospective studies as a basis for phase 5 evaluations.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Biomarcadores , Encéfalo/diagnóstico por imagem , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Biomarcadores/metabolismo , Encéfalo/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Demência/diagnóstico por imagem , Glucose/metabolismo , Humanos , Reprodutibilidade dos Testes
14.
Neurobiol Aging ; 52: 228-242, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28317651

RESUMO

The use of biomarkers (BMs) for accurate diagnosis of Alzheimer's disease (AD) has been proposed by recent diagnostic criteria; however, their maturity is not sufficient to grant implementation in the clinical routine. A proper diagnostic process requires not only confirmation of the disease but also the exclusion of similar disorders entering differential diagnosis, like dementia with Lewy bodies (DLB). This review is aimed at evaluating the clinical validity of 123I-ioflupane brain single photon emission tomography and 123I-MIBG cardiac scintigraphy as imaging BMs for DLB. For this purpose, we used an adapted version of the 5-phase oncology framework for BMs development. A review of the literature was conducted using homogenous search criteria with other BMs addressed in parallel reviews. Results of our literature search showed that the rationale for the use of both BMs in the differential diagnosis of DLB and AD is strong (phase 1) and that they allow a good discrimination ability (phase 2), but studies investigating BMs distribution antemortem and postmortem on pathology are lacking. Moreover, thresholds for test positivity have not been defined for 123I-MIBG. The 2 BMs have not been yet assessed in early phases of DLB and AD (phase 3). No phase 4 and phase 5 studies have so far been carried out. This review highlights the priorities to address in future investigations to enable the proper use of 123I-ioflupane and 123I-MIBG for the differential diagnosis of dementia.


Assuntos
3-Iodobenzilguanidina , Doença de Alzheimer/diagnóstico por imagem , Biomarcadores , Coração/diagnóstico por imagem , Radioisótopos do Iodo , Doença por Corpos de Lewy/diagnóstico por imagem , Nortropanos , Cintilografia , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Cognitiva/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Reprodutibilidade dos Testes
15.
Clin Nucl Med ; 42(5): e242-e246, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28240662

RESUMO

PURPOSE: The aims of this study were to assess the intraindividual performance of F-fluorocholine (FCH) and C-acetate (ACE) PET studies for restaging of recurrent prostate cancer (PCa), to correlate PET findings with long-term clinical and imaging follow-up, and to evaluate the impact of PET results on patient management. METHODS: Thirty-three PCa patients relapsing after radical prostatectomy (n = 10, prostate-specific antigen [PSA] ≤3 ng/mL), primary radiotherapy (n = 8, prostate-specific antigen ≤5 ng/mL), or radical prostatectomy + salvage radiotherapy (n = 15) underwent ACE and FCH PET-CT (n = 29) or PET-MRI (n = 4) studies in a randomized sequence 0 to 21 days apart. RESULTS: The detection rate for ACE was 66% and for FCH was 60%. Results were concordant in 79% of the cases (26/33) and discordant in 21% (retroperitoneal, n = 5; pararectal, n = 1; and external iliac nodes, n = 1). After a median FU of 41 months (n = 32, 1 patient lost to FU), the site of relapse was correctly identified by ACE and FCH in 53% (17/32) and 47% (15/32) of the patients, respectively (2 M1a patients ACE+/FCH-), whereas in 6 of 32 patients the relapse was not localized. Treatment approach was changed in 11 (34.4%) of 32 patients and 9 (28%) of 32 patients restaged with ACE and FCH PET, respectively. CONCLUSIONS: In early recurrent PCa, ACE and FCH showed minor discrepancies, limited to nodal staging and mainly in the retroperitoneal area, with true positivity of PET findings confirmed in half of the cases during FU. Treatment approach turned out to be influenced by ACE or FCH PET studies in one third of the patients.


Assuntos
Acetatos , Carbono , Colina/análogos & derivados , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/diagnóstico por imagem , Compostos Radiofarmacêuticos , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal
16.
Front Oncol ; 6: 73, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27065024

RESUMO

Salvage radiotherapy (SRT) represents the main treatment option for relapsing prostate cancer in patients after radical prostatectomy. Several open questions remain unanswered in terms of target volumes definition and delivered doses for SRT: the effective dose necessary to achieve biochemical control in the SRT setting may be different if the tumor recurrence is micro- or macroscopic. At the same time, irradiation of only the prostatic bed or of the whole pelvis will depend on the localization of the recurrence, local or locoregional. In the "theragnostic imaging" era, molecular imaging using positron emission tomography (PET) constitutes a useful tool for clinicians to define the site of the recurrence, the extent of disease, and individualize salvage treatments. The best option currently available in clinical routine is the combination of radiolabeled choline PET imaging and multiparametric magnetic resonance imaging (MRI), associating the nodal and distant metastases identification based on PET with the local assessment by MRI. A new generation of targeted tracers, namely, prostate-specific membrane antigen, show promising results, with a contrast superior to choline imaging and a higher detection rate even for low prostate-specific antigen levels; validation studies are ongoing. Finally, imaging targeting bone remodeling, using whole-body SPECT-CT, is a relevant complement to molecular/metabolic PET imaging when bone involvement is suspected.

17.
Eur Radiol ; 26(7): 2297-307, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26477029

RESUMO

OBJECTIVE: To evaluate the performance of 18F-fluorodeoxyglucose (FDG) positron emission tomography magnetic resonance imaging (PET/MR) for preoperative breast cancer staging. METHODS: Preoperative PET/MR exams of 58 consecutive women with breast cancer were retrospectively reviewed. Histology and mean follow-up of 26 months served as gold standard. Four experienced readers evaluated primary lesions, lymph nodes and distant metastases with contrast-enhanced MRI, qualitative/quantitative PET, and combined PET/MR. ROC curves were calculated for all modalities and their combinations. RESULTS: The study included 101 breast lesions (83 malignant, 18 benign) and 198 lymph node groups, (34 malignant, 164 benign). Two patients had distant metastases. Areas under the curve (AUC) for breast cancer were 0.9558, 0.8347 and 0.8855 with MRI, and with qualitative and quantitative PET/MR, respectively (p = 0.066). Sensitivity for primary cancers with MRI and quantitative PET/MR was 100 % and 77 % (p = 0.004), and for lymph nodes 88 % and 79 % (p = 0.25), respectively. Specificity for MRI and PET/MR for primary cancers was 67 % and 100 % (p = 0.03) and for lymph nodes 98 % and 100 % (p = 0.25). CONCLUSIONS: In breast cancer patients, MRI alone has the highest sensitivity for primary tumours. For nodal metastases, both MRI and PET/MR are highly specific. KEY POINTS: • MRI alone and PET/MR have a similar overall diagnostic performance. • MRI alone has a higher sensitivity than PET/MR for local tumour assessment. • Both MRI and PET/MR have a limited sensitivity for nodal metastases. • Positive lymph nodes on MRI or PET/MR do not require presurgical biopsy.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Fluordesoxiglucose F18 , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Cuidados Pré-Operatórios/métodos , Compostos Radiofarmacêuticos , Adulto , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
18.
Surg Radiol Anat ; 38(3): 361-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26553051

RESUMO

PURPOSE: Many regions worldwide report difficulties in recruiting applicants to surgery. One strategy proposed to reverse this trend consists of early exposure of medical students to the field. Against this backdrop, the present study presents an innovative approach for anatomy teaching, integrating a surgically relevant trend: 3D printing. METHODS: Whole-body computed tomography (CT) was made of two cadavers. Twelve students performed measurements and 3D reconstructions of selected anatomical structures (Osirix, Mimics). 3D printed (3DP) models were obtained (ZPrinter 310 Plus), and the students completed the analogous measurements on these replicas. Finally, classical anatomical dissection was performed and the same parameters were measured. The differences between the values obtained by the three modalities were submitted to standard statistical analysis (Wilcoxon two-tail paired test). RESULTS: Qualitative comparison of the digital 3D reconstructions based on the students' manual CT segmentation and the anatomical reality showed excellent correlation. Quantitatively, the values measured on the CT images and the physical models created by 3D printing differed from those measured on the cadavers by less than 2 mm. Students were highly appreciative of the approach (CT, 3DP, cadaver). Their average satisfaction score was 5.8 on a 1-6 scale. CONCLUSIONS: This study shows that the approach proposed can be achieved. The results obtained also show that CT-based 3D printed models are close to the authentic anatomic reality. The program allows early and interactive exposure of medical students to a surgically relevant trend-in this case 3D printing.


Assuntos
Anatomia/educação , Impressão Tridimensional , Adulto , Idoso , Dissecação , Estudos de Viabilidade , Feminino , Humanos , Imageamento Tridimensional , Masculino , Projetos Piloto , Tomografia Computadorizada por Raios X , Imagem Corporal Total
19.
Int J Comput Assist Radiol Surg ; 11(5): 733-43, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26210940

RESUMO

PURPOSE: The purpose of the present study is to apply kinetic analysis to investigate exercise-related changes in the metabolism of the skeletal muscle of the rat hindlimb by [[Formula: see text]]acetate positron emission tomography and computed tomography (PET/CT). METHODS: Contractions were induced in Wistar rats' left hindlimb by electrostimulation of the Vastus Lateralis muscle motor point. After 15 min of muscle contractions, [[Formula: see text]]acetate was injected and PET/CT of both hindlimbs was acquired. The resting hindlimb was used as a control reference. The kinetic parameters [Formula: see text] and [Formula: see text] were calculated for the target muscles (exercised and control) and correlated with the corresponding standardized uptake values (SUVs). The ratio between each kinetic parameter values and the SUV extracted for the exercised muscle and the muscle at rest was computed ([Formula: see text] and [Formula: see text], respectively). RESULTS: Kinetic analysis quantitatively confirmed that net tracer uptake ([Formula: see text]) and washout ([Formula: see text]) were significantly higher in exercised muscles ([Formula: see text] for exercised muscles vs. [Formula: see text] for resting muscles, [Formula: see text]; [Formula: see text] for exercised muscle vs. [Formula: see text] for resting muscle, [Formula: see text]). On the other hand, SUV was not significantly different between active and inactive muscles ([Formula: see text] for exercised muscles vs. [Formula: see text] for resting muscles). Linear regression analysis revealed a good correlation ([Formula: see text]) between net tracer uptake ratio ([Formula: see text]) and the SUV ratio [Formula: see text]). A lower correlation was found between the net tracer washout ratio ([Formula: see text]) and the SUV ratio ([Formula: see text]). CONCLUSION: The present study showed that kinetic modelling can detect changes between active and inactive skeletal muscles with a higher sensitivity with respect to the SUV, when performed with [[Formula: see text]]acetate PET/CT.


Assuntos
Membro Posterior/diagnóstico por imagem , Contração Muscular/fisiologia , Músculo Esquelético/diagnóstico por imagem , Acetatos , Animais , Radioisótopos de Carbono , Membro Posterior/irrigação sanguínea , Membro Posterior/metabolismo , Cinética , Masculino , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Ratos , Ratos Wistar
20.
Rev Med Suisse ; 11(479): 1340-4, 2015 Jun 17.
Artigo em Francês | MEDLINE | ID: mdl-26255495

RESUMO

CERN-MEDICIS is a facility dedicated to research and development in life science and medical applications. The research platform was inaugurated in October 2014 and will produce an increasing range of innovative isotopes using the proton beam of ISOLDE for fundamental studies in cancer research, for new imaging and therapy protocols in cell and animal models and for preclinical trials, possibly extended to specific early phase clinical studies (phase 0) up to phase I trials. CERN, the University Hospital of Geneva (HUG), the University Hospital of Lausanne (CHUV), the Swiss Institute for Experimental Cancer (ISREC) at Swiss Federal Institutes of Technology (EPFL) that currently support the project will benefit of the initial production that will then be extended to other centers.


Assuntos
Laboratórios , Radioisótopos , Humanos , Medicina Nuclear , Suíça
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