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1.
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
2.
Eur J Nucl Med Mol Imaging ; 46(2): 385-395, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30269157

RESUMO

PURPOSE: Mutations of cholinergic neuronal nicotinic receptors have been identified in the autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE), associated with changes on PET images using [18F]-F-85380-A (F-A-85380), an α4ß2 nicotinic receptor ligand. The aim of the present study was to evaluate potential changes in nicotinic receptor availability in other types of epilepsy. METHODS: We included 34 male participants, 12 patients with idiopathic generalized epilepsy (IGE), 10 with non-lesional diurnal focal epilepsy, and 12 age-matched healthy controls. All patients underwent PET/CT using F-A-85380 and [18F]-fluorodeoxyglucose (FDG), 3D T1 MRI and diffusion tensor imaging (DTI). F-A-85380 and FDG images were compared with the control group using a voxel-wise (SPM12) and a volumes of interest (VOI) analysis. RESULTS: In the group of patients with IGE, the voxel-wise and VOI analyses showed a significant increase of F-A-85380 ratio index of binding potential (BPRI, corresponding to the receptor availability) in the anterior cingulate cortex (ACC), without structural changes on MRI. At an individual level, F-A-85380 BPRI increase in the ACC could distinguish IGE patients from controls and from patients with focal epilepsy with good accuracy. CONCLUSIONS: We observed focal changes of density/availability of nicotinic receptors in IGE, namely an increase in the ACC. These data suggest that the modulation of α4ß2 nicotinic receptors plays a role not only in ADNFLE, but also in other genetic epileptic syndromes such as IGE and could serve as a biomarker of epilepsy syndromes with a genetic background.


Assuntos
Epilepsia Generalizada/diagnóstico por imagem , Epilepsia Generalizada/metabolismo , Receptores Nicotínicos/metabolismo , Adolescente , Adulto , Biomarcadores/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto Jovem
3.
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
4.
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
5.
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
6.
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
7.
Eur J Nucl Med Mol Imaging ; 42(7): 1133-43, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25893383

RESUMO

PURPOSE: In patients with pharmacoresistant focal epilepsy, resection of the epileptic focus can lead to freedom from seizures or significant improvement in well-selected candidates. Localization of the epileptic focus with multimodal concordance is crucial for a good postoperative outcome. Beyond the detection of epileptogenic lesions on structural MRI and focal hypometabolism on FDG PET, EEG-based Electric Source Imaging (ESI) and simultaneous EEG and functional MRI (EEG-fMRI) are increasingly applied for mapping epileptic activity. We here report presurgical multimodal interictal imaging using a hybrid PET/MR scanner for single-session FDG PET, MRI, EEG-fMRI and ESI. METHODS: This quadrimodal imaging procedure was performed in a single session in 12 patients using a high-density (256 electrodes) MR-compatible EEG system and a hybrid PET/MR scanner. EEG was used to exclude subclinical seizures during uptake of the PET tracer, to compute ESI on interictal epileptiform discharges and to guide fMRI analysis for mapping haemodynamic changes correlated with interictal epileptiform activity. RESULTS: The whole multimodal recording was performed in less than 2 hours with good patient comfort and data quality. Clinically contributory examinations with at least two modalities were obtained in nine patients and with all modalities in five patients. CONCLUSION: This single-session quadrimodal imaging procedure provided reliable and contributory interictal clinical data. This procedure avoids multiple scanning sessions and is associated with less radiation exposure than PET-CT. Moreover, it guarantees the same medication level and medical condition for all modalities. The procedure improves workflow and could reduce the duration and cost of presurgical epilepsy evaluations.


Assuntos
Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Eletroencefalografia/métodos , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Adolescente , Adulto , Criança , Epilepsia Resistente a Medicamentos/diagnóstico , Epilepsia Resistente a Medicamentos/cirurgia , Eletroencefalografia/instrumentação , Feminino , Humanos , Imageamento por Ressonância Magnética/instrumentação , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/instrumentação , Tomografia por Emissão de Pósitrons/instrumentação , Período Pré-Operatório
8.
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
9.
Stroke ; 45(12): 3561-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25370581

RESUMO

BACKGROUND AND PURPOSE: We investigated whether uptake of (18)fluoro-2-deoxy-d-glucose (18FDG) positron emission tomography-computed tomography (PET-CT) correlated to clinical symptoms and presence of microembolic signals (MES) detected by transcranial Doppler in patients with carotid stenosis. METHODS: 18FDG-PET-CT and MES detection was performed in consecutive patients with 50% to 99% symptomatic or asymptomatic carotid stenoses. Uptake index was defined by a target to background ratio (TBR) between maximum standardized uptake value of the carotid plaque and the mean standardized uptake value of the jugular veins. End points for analysis were presence of symptoms and presence of MES. RESULTS: We included 123 stenosis derived from 110 patients, 60 symptomatic and 63 asymptomatic. MES positive (+) lesions were found in 16%. TBR values were higher in symptomatic compared with asymptomatic (median 2.07 versus 1.78; P<0.0018) and in MES+ compared with MES- plaques (median 2.14 versus 1.86; P<0.008). TBR values were also higher in asymptomatic MES+ compared with MES- plaques (median 1.97 versus 1.76; P<0.03). The best TBR threshold value for symptomatic versus asymptomatic, for MES+ versus MES-, for symptomatic MES+ versus symptomatic or asymptomatic MES-, and for asymptomatic MES+ versus asymptomatic MES- plaques was 1.9. Sensitivity/specificity were, respectively, 56/77%, 73/63%, 79/64%, and 80/77%. We found a strong correlation between number of MES and TBR values (ρ 0.26; P=0.0043). CONCLUSIONS: 18FDG-PET-CT accurately detected high-risk carotid plaques. Also given its strong correlation to MES, 18FDG-PET-CT may be a useful tool in clinical practice.


Assuntos
Estenose das Carótidas/diagnóstico , Fluordesoxiglucose F18 , Embolia Intracraniana/diagnóstico , Imagem Multimodal/métodos , Compostos Radiofarmacêuticos , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Curva ROC , Fatores de Risco , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler Transcraniana
10.
Eur J Nucl Med Mol Imaging ; 41(3): 462-75, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24108458

RESUMO

PURPOSE: Our objectives were to assess the quality of PET images and coregistered anatomic images obtained with PET/MR, to evaluate the detection of focal uptake and SUV, and to compare these findings with those of PET/CT in patients with head and neck tumours. METHODS: The study group comprised 32 consecutive patients with malignant head and neck tumours who underwent whole-body (18)F-FDG PET/MR and PET/CT. PET images were reconstructed using the attenuation correction sequence for PET/MR and CT for PET/CT. Two experienced observers evaluated the anonymized data. They evaluated image and fusion quality, lesion conspicuity, anatomic location, number and size of categorized (benign versus assumed malignant) lesions with focal uptake. Region of interest (ROI) analysis was performed to determine SUVs of lesions and organs for both modalities. Statistical analysis considered data clustering due to multiple lesions per patient. RESULTS: PET/MR coregistration and image fusion was feasible in all patients. The analysis included 66 malignant lesions (tumours, metastatic lymph nodes and distant metastases), 136 benign lesions and 470 organ ROIs. There was no statistically significant difference between PET/MR and PET/CT regarding rating scores for image quality, fusion quality, lesion conspicuity or anatomic location, number of detected lesions and number of patients with and without malignant lesions. A high correlation was observed for SUVmean and SUVmax measured on PET/MR and PET/CT for malignant lesions, benign lesions and organs (ρ = 0.787 to 0.877, p < 0.001). SUVmean and SUVmax measured on PET/MR were significantly lower than on PET/CT for malignant tumours, metastatic neck nodes, benign lesions, bone marrow, and liver (p < 0.05). The main factor affecting the difference between SUVs in malignant lesions was tumour size (p < 0.01). CONCLUSION: In patients with head and neck tumours, PET/MR showed equivalent performance to PET/CT in terms of qualitative results. Comparison of SUVs revealed an excellent correlation for measurements on both modalities, but underestimation of SUVs measured on PET/MR as compared to PET/CT.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imageamento por Ressonância Magnética , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Carcinoma de Células Escamosas/diagnóstico , Feminino , Fluordesoxiglucose F18/farmacocinética , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/farmacocinética
11.
Eur J Nucl Med Mol Imaging ; 41(1): 68-78, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24104592

RESUMO

PURPOSE: (18)F-Fluorocholine (FCH) and (11)C-acetate (ACE) PET are widely used for detection of recurrent prostate cancer (PC). We present the first results of a comparative, prospective PET/CT study of both tracers evaluated in the same patients presenting with recurrence and low PSA to compare the diagnostic information provided by the two tracers. METHODS: The study group comprised 23 patients studied for a rising PSA level after radical prostatectomy (RP, 7 patients, PSA ≤ 3 ng/ml), curative radiotherapy (RT, 7 patients, PSA ≤ 5 ng/ml) or RP and salvage RT (9 patients, PSA ≤ 5 ng/ml). Both FCH and ACE PET/CT scans were performed in a random sequence a median of 4 days (range 0 to 11 days) apart. FCH PET/CT was started at injection (307 ± 16 MBq) with a 10-min dynamic acquisition of the prostate bed, followed by a whole-body PET scan and late (45 min) imaging of the pelvis. ACE PET/CT was performed as a double whole-body PET scan starting 5 and 22 min after injection (994 ± 72 MBq), and a late view (45 min) of the prostate bed. PET/CT scans were blindly reviewed by two independent pairs of two experienced nuclear medicine physicians, discordant subgroup results being discussed to reach a consensus for positive, negative end equivocal results. RESULTS: PET results were concordant in 88 out of 92 local, regional and distant findings (Cohen's kappa 0.929). In particular, results were concordant in all patients concerning local status, bone metastases and distant findings. Lymph-node results were concordant in 19 patients and different in 4 patients. On a per-patient basis results were concordant in 22 of 23 patients (14 positive, 5 negative and 3 equivocal). In only one patient was ACE PET/CT positive for nodal metastases while FCH PET/CT was overall negative; interestingly, the ACE-positive and FCH-negative lymph nodes became positive in a second FCH PET/CT scan performed a few months later. CONCLUSION: Overall, ACE and FCH PET/CT showed excellent concordance, on both a per-lesion and a per-patient basis, suggesting that both tracers perform equally for recurrent prostate cancer staging.


Assuntos
Acetatos , Colina/análogos & derivados , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/diagnóstico , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Radioisótopos de Carbono , Radioisótopos de Flúor , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Prostatectomia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia
12.
Eur J Nucl Med Mol Imaging ; 41(9): 1744-55, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24841413

RESUMO

PURPOSE: To report the first results of hybrid (18)F-fluorocholine PET/MRI imaging for the detection of prostate cancer. METHODS: This analysis included 26 consecutive patients scheduled for prostate PET/MRI before radical prostatectomy. The examinations were performed on a hybrid whole-body PET/MRI scanner. The MR acquisitions which included T2-weighted, diffusion-weighted and dynamic contrast-enhanced sequences were followed during the same session by whole-body PET scans. Parametric maps were constructed to measure normalized T2-weighted intensity (nT2), apparent diffusion coefficient (ADC), volume transfer constant (K (trans)), extravascular extracellular volume fraction (v e) and standardized uptake values (SUV). With pathology as the gold standard, ROC curves were calculated using logistic regression for each parameter and for the best combination with and without PET to obtain a MR model versus a PETMR model. RESULTS: Of the 26 patients initially selected, 3 were excluded due to absence of an endorectal coil (2 patients) or prosthesis artefacts (1 patient). In the whole prostate, the area under the curve (AUC) for SUVmax, ADC, nT2, K (trans) and v e were 0.762, 0.756, 0.685, 0.611 and 0.529 with a best threshold at 3.044 for SUVmax and 1.075 × 10(-3) mm(2)/s for ADC. The anatomical distinction between the transition zone and the peripheral zone showed the potential of the adjunctive use of PET. In the peripheral zone, the AUC of 0.893 for the PETMR model was significantly greater (p = 0.0402) than the AUC of 0.84 for the MR model only. In the whole prostate, no relevant correlation was observed between ADC and SUVmax. The SUVmax was not affected by the Gleason score. CONCLUSION: The performance of a hybrid whole-body (18)F-fluorocholine PET/MRI scan in the same session combined with a prostatic MR examination did not interfere with the diagnostic accuracy of the MR sequences. The registration of the PET data and the T2 anatomical MR sequence data allowed precise localization of hypermetabolic foci in the prostate. While in the transition zone the adenomatous hyperplasia interfered with cancer detection by PET, the quantitative analysis tool performed well for cancer detection in the peripheral zone.


Assuntos
Colina/análogos & derivados , Imageamento por Ressonância Magnética , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Estudos de Viabilidade , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias da Próstata/patologia , Curva ROC
13.
Eur Heart J ; 34(27): 2063-73, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23487518

RESUMO

AIMS: To investigate the effect of surgical gastric bypass-induced weight loss and related alterations in endocannabinoids (ECs) and adipocytokine plasma levels on coronary circulatory dysfunction in morbidly obese (MOB) individuals. METHODS AND RESULTS: Myocardial blood flow (MBF) responses to cold pressor test (CPT) from rest (ΔMBF) and during pharmacologically induced hyperaemia were measured with ¹³N-ammonia PET/CT in 18 MOB individuals with a body mass index (BMI) > 40 kg/m² at baseline and after a median follow-up period of 22 months. Gastric bypass intervention decreased BMI from a median of 44.8 (inter-quartile range: 43.3, 48.2) to 30.8 (27.3, 34.7) kg/m² (P < 0.0001). This decrease in BMI was accompanied by a marked improvement in endothelium-related ΔMBF to CPT and hyperaemic MBFs, respectively [0.34 (0.18, 0.41) from 0.03 (-0.08, 0.15) mL/g/min, P = 0.002; and 2.51 (2.17, 2.64) from 1.53 (1.39, 2.18) mL/g/min, P < 0.001]. There was an inverse correlation between decreases in plasma concentrations of the EC anandamide and improvement in ΔMBF to CPT (r = -0.59, P = 0.009), while increases in adiponectin plasma levels correlated positively with hyperaemic MBFs (r = 0.60, P = 0.050). Conversely, decreases in leptin plasma concentrations were not observed to correlate with the improvement in coronary circulatory function (r = 0.22, P = 0.400, and r = -0.31, P = 0.250). CONCLUSIONS: Gastric bypass-related reduction of BMI in MOB individuals beneficially affects coronary circulatory dysfunction. The dysbalance between ECs and adipocytokines appears to be an important determinant of coronary circulatory function in obesity.


Assuntos
Adipocinas/metabolismo , Circulação Coronária/fisiologia , Endocanabinoides/metabolismo , Derivação Gástrica , Obesidade Mórbida/fisiopatologia , Tecido Adiposo/metabolismo , Adulto , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Obesidade Mórbida/cirurgia , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Estresse Fisiológico , Tomografia Computadorizada por Raios X , Sistema Vasomotor/fisiologia , Redução de Peso/fisiologia
14.
Rev Med Suisse ; 10(453): 2302-5, 2014 Dec 03.
Artigo em Francês | MEDLINE | ID: mdl-25626245

RESUMO

In 2014, Geneva University Hospital has opened the first certified prostate cancer Center of western Switzerland. It incorporates 29 entities implicated in the diagnosis and treatment of this disease, thereby assuring that all available ressources are made available to patients, regardless of the division to which they were initially referred. The main strength of the Center lies in the synergy generated by its multidisciplinary tumor board. Furthermore, regular conferences, staff meetings, propectively held registers and the yearly re-certification audit support its constant quality improvement.


Assuntos
Institutos de Câncer/organização & administração , Hospitais Universitários/organização & administração , Neoplasias da Próstata/terapia , Certificação , Procedimentos Clínicos/organização & administração , Humanos , Comunicação Interdisciplinar , Masculino , Equipe de Assistência ao Paciente/organização & administração , Suíça
15.
J Clin Microbiol ; 51(8): 2769-71, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23698520

RESUMO

A 49-year-old woman with a 15-year history of HIV-hepatitis C virus coinfection had aortic valve and ascending aorta replacement in 2007. She presented with abdominal pain, episodic diarrhea, and profuse sweating in 2010. Thoracoabdominal positron emission tomography-computed tomography finally suggested infectious aortitis, a diagnosis confirmed by a blood culture positive for Capnocytophaga canimorsus.


Assuntos
Aortite/diagnóstico , Aortite/microbiologia , Capnocytophaga/isolamento & purificação , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/microbiologia , Aorta/patologia , Aortite/patologia , Feminino , Infecções por Bactérias Gram-Negativas/patologia , Infecções por HIV/complicações , Hepatite C Crônica/complicações , Humanos , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Infecções Relacionadas à Prótese/patologia , Radiografia Abdominal , Radiografia Torácica
16.
Eur J Nucl Med Mol Imaging ; 40(6): 842-52, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23436068

RESUMO

PURPOSE: Head and neck squamous cell carcinoma (HNSCC) may cause a decreased apparent diffusion coefficient (ADC) on diffusion-weighted magnetic resonance imaging (DW MRI) and an increased standardized uptake value (SUV) on fluorodeoxyglucose (FDG) positron emission tomography (PET/CT). We analysed the reproducibility of ADC and SUV measurements in HNSCC and evaluated whether these biomarkers are correlated or independent. METHODS: This retrospective analysis of DW MRI and FDG PET/CT data series included 34 HNSCC in 33 consecutive patients. Two experienced readers measured tumour ADC and SUV values independently. Statistical comparison and correlation with histopathology was done. Intra- and inter-observer agreement for ADC and SUV measurements was assessed. RESULTS: Intraclass correlation coefficient (ICC) analysis showed almost perfect reproducibility (>0.90) for ADCmean, ADCmin, SUVmax and SUVmean values for intra-observer and inter-observer agreement. Mean ADCmean and ADCmin in HNSCC were 1.05 ± 0.34 × 10(-3) mm(2)/s and 0.65 ± 0.29 × 10(-3) mm(2)/s, respectively. Mean SUVmean and mean SUVmax were 7.61 ± 3.87 and 12.8 ± 5.0, respectively. Although statistically not significant, a trend towards higher SUV and lower ADC was observed with increasing tumour dedifferentiation. Pearson's correlation analysis showed no significant correlation between ADC and SUV measurements (r -0.103, -0.051; p 0.552, 0.777). CONCLUSION: Our data suggest that ADC and SUV values are reproducible and independent biomarkers in HNSCC.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Imagem de Difusão por Ressonância Magnética , Fluordesoxiglucose F18/farmacologia , Neoplasias de Cabeça e Pescoço/diagnóstico , Imageamento por Ressonância Magnética , Imagem Multimodal , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Diferenciação Celular , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Cintilografia , Recidiva , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
17.
Acta Oncol ; 52(8): 1622-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23544357

RESUMO

BACKGROUND: Substantial survival may be observed with oligometastatic prostate cancer. Combining androgen deprivation (AD) and high-dose external beam radiotherapy (RT) to isolated regional or distant lesions may be proposed for these patients and the outcome of this strategy is the purpose of the present report. MATERIAL AND METHODS: From 2003 to 2010, 50 prostate cancer patients were diagnosed with synchronous (n = 7) or metachronous (n = 43) oligometastases (OM). Among the relapsing patients, the recurrence occurred after radical prostatectomy in 33 patients and curative RT (± AD) in 10 patients. The median age at diagnosis was 63 years (range, 48-82). All patients underwent a bone scan and 18F-choline or 11C-acetate PET-CT at the time of diagnosis or relapse, showing regional and/or distant nodal and bone and/or visceral metastases in 33 and 17 patients, respectively. The median delivered effective dose was 64 Gy. All but one patient received neo-adjuvant and concomitant AD. RESULTS: After a median follow-up of 31 months (range, 9-89) the three-year biochemical relapse-free survival (bRFS), clinical failure-free survival, and overall survival rates were 54.5%, 58.6% and 92%, respectively. No grade 3 toxicity was observed. Improved bRFS was found to be significantly associated with the number of OM. The three-year bRFS was 66.5% versus 36.4% for patients with 1 and > 1 OMs (p = 0.031). A normalised total dose (NTD in 2 Gy/fraction, alpha/beta = 2 Gy) above 64 Gy was also correlated with a better three-year bRFS compared to lower doses: 65% vs. 41.8%, respectively (p = 0.005). On multivariate analysis, only the NTD > 64 Gy retained statistical significance (HR: 0.37, 95% CI 0.15-0.93). CONCLUSION: Oligometastatic patients may be successfully treated with short AD and high-dose irradiation to the metastatic lesions. High dose improves bRFS. Such a treatment strategy may hypothetically succeed to prolong the failure-free interval between two consecutive AD courses.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Quimiorradioterapia , Recidiva Local de Neoplasia/terapia , Neoplasias da Próstata/terapia , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta à Radiação , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Metástase Neoplásica , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Prognóstico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Compostos Radiofarmacêuticos , Radioterapia Conformacional , Taxa de Sobrevida , Tomografia Computadorizada por Raios X
18.
MAGMA ; 26(1): 57-69, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23008016

RESUMO

Magnetic resonance imaging (MRI) is the examination method of choice for the diagnosis of a variety of diseases. MRI allows us to obtain not only anatomical information but also identification of physiological and functional parameters such as networks in the brain and tumor cellularity, which plays an increasing role in oncologic imaging, as well as blood flow and tissue perfusion. However, in many cases such as in epilepsy, degenerative neurological diseases and oncological processes, additional metabolic and molecular information obtained by PET can provide essential complementary information for better diagnosis. The combined information obtained from MRI and PET acquired in a single imaging session allows a more accurate localization of pathological findings and better assessment of the underlying physiopathology, thus providing a more powerful diagnostic tool. Two hundred and twenty-one patients were scanned from April 2011 to January 2012 on a Philips Ingenuity TF PET/MRI system. The purpose of this review article is to provide an overview of the techniques used for the optimization of different protocols performed in our hospital by specialists in the following fields: neuroradiology, head and neck, breast, and prostate imaging. This paper also discusses the different problems encountered, such as the length of studies, motion artifacts, and accuracy of image fusion including physical and technical aspects, and the proposed solutions.


Assuntos
Encefalopatias/diagnóstico , Protocolos Clínicos , Imageamento por Ressonância Magnética/métodos , Neoplasias/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Encefalopatias/diagnóstico por imagem , Encefalopatias/patologia , Criança , Feminino , Fluordesoxiglucose F18 , Humanos , Imageamento por Ressonância Magnética/instrumentação , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Posicionamento do Paciente , Tomografia por Emissão de Pósitrons/instrumentação , Compostos Radiofarmacêuticos , Fatores de Tempo , Imagem Corporal Total
19.
Surg Innov ; 20(2): 158-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22549904

RESUMO

The increased distance between surgeon and surgical field is a significant problem in laparoscopic surgery. Robotic surgery, although providing advantages for the operator, increases this gap by completely removing force feedback. Enhancement with visual tools can therefore be beneficial. The goal of this preliminary work was to create a custom plugin for OsiriX to display volume-rendered images in the da Vinci surgeon's console. The TilePro multi-input display made the generated stereoscopic pairs appear to have depth. Tumor position, vascular supply, spatial location, and relationship between organs appear directly within the surgeon's field of view. This study presents a case of totally robotic right colectomy for cancer using this new technology. Sight diversion was no longer necessary. Depth perception was subjectively perceived as profitable. Total immersion in the operative field helped compensate for the lack of tactile feedback specific to robotic intervention. This innovative tool is a step forward toward augmented-reality robot-assisted surgery.


Assuntos
Adenocarcinoma/cirurgia , Neoplasias do Colo/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Imageamento Tridimensional/métodos , Laparoscopia/métodos , Robótica/métodos , Cirurgia Assistida por Computador/métodos , Idoso , Procedimentos Cirúrgicos do Sistema Digestório/instrumentação , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Laparoscopia/instrumentação , Robótica/instrumentação , Cirurgia Assistida por Computador/instrumentação
20.
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
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