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1.
Artigo em Japonês | MEDLINE | ID: mdl-34305056

RESUMO

PURPOSE: Quantitative analysis using a standardized uptake value (SUV) has become possible for single-photon emission computed tomography-computed tomography (SPECT-CT) of bone. However, previous research was targeted to the trunk area, and there are few studies for the head and neck region. Therefore, the purpose of this study was to determine the optimal image reconstruction conditions for bone SPECT of the head and neck using a phantom study. METHOD: The radioactivity concentration of the 99mTc solution enclosed in the cylindrical phantom was set to the same count rate as in clinical cases, and six hot spheres (10, 13, 17, 22, 28, 37 mm) with four times the concentration were placed within it. The image reconstruction was 3D-OSEM, and the reconstruction conditions were varied by the number of iterative updates and the width of the Gaussian filter. Quantitative evaluations of the image quality were performed using the % contrast, background variability, and SUV for the hot spheres and background. A visual evaluation was performed by four observers to determine the optimal image reconstruction conditions for bone SPECT of the head and neck region. RESULT: The concentration of the 99mTc solution enclosed in the phantom was 6.95 (kBq/ml). Based on the results of the quantitative and visual evaluations, the optimal image reconstruction conditions were iterative updates=60 (subset: 10, iteration: 6) and a Gaussian filter of 7.8 mm. CONCLUSION: The optimal image reconstruction conditions were subset=10, iterations=6, and a Gaussian filter of 7.8 mm.


Assuntos
Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada de Emissão de Fóton Único , Processamento de Imagem Assistida por Computador , Pescoço/diagnóstico por imagem , Imagens de Fantasmas
2.
Nan Fang Yi Ke Da Xue Xue Bao ; 41(7): 1093-1100, 2021 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-34308862

RESUMO

OBJECTIVE: To analyze single-photon emission tomography (SPECT) images of cerebral blood flow perfusion using an easy Z-score imaging system (eZIS) and explore the value of SPECT and eZIS in early diagnosis of Alzheimer's disease (AD). METHODS: We retrospectively analyzed the clinical data of 71 subjects undergoing brain perfusion SPECT examination in our department from September, 2018 to September, 2020 and identified 31 eligible subjects for this study. Among these subjects, according to the NIA-AA criteria (2011 edition), 12 were diagnosed with mild cognitive impairment due to AD (MCI) and 11 with AD dementia stage (AD); 8 elderly subjects were healthy without cognitive impairment (NC). All these subjects underwent brain perfusion SPECT, and eZIS-assisted analysis was used to obtain the index values (severity, range and ratio). The differences in the severity, extent and ratio among the 3 groups were compared, and the diagnostic efficacy of single and joint analysis of the 3 indexes for early AD was analyzed. RESULTS: There was no significant difference in gender, age and education level among the 3 groups (P>0.05). Compared with those in NC group, the Mini Mental State Examination Scale (MMSE) scores were significantly lowered in AD group and MCI group; the MMSE score was significantly lower in AD group than in MCI group (P < 0.05). The patients with AD had significantly greater disease severity and extent than those with MCI group; the severity, range and ratio in both AD group and MCI group were significantly higher than those of NC group, but the ratio did not differ significantly between AD group and MCI group (P>0.05). In single index analysis, severity had the highest diagnostic performance (AUC=0.911) and sensitivity (87.0%); the diagnostic performance and sensitivity of joint analysis were better than those of single analysis, and joint analysis of range and ratio showed high diagnostic performance (AUC=0.948) and sensitivity (87.0%). CONCLUSION: The analysis of brain perfusion SPECT using an eZIS program can be useful for early diagnosis of AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Idoso , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Disfunção Cognitiva/diagnóstico por imagem , Diagnóstico Precoce , Humanos , Perfusão , Estudos Retrospectivos , Tomografia Computadorizada de Emissão de Fóton Único
3.
Sensors (Basel) ; 21(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066113

RESUMO

In this work, we propose and analyze a new concept of gamma ray imaging that corresponds to a gamma camera with a mobile collimator, which can be used in vivo, during surgical interventions for oncological patients for localizing regions of interest such as tumors or ganglia. The benefits are a much higher sensitivity, better image quality and, consequently, a dose reduction for the patient and medical staff. This novel approach is a practical solution to the overlapping problem which is inherent to multi-pinhole gamma camera imaging and single photon emission computed tomography and which translates into artifacts and/or image truncation in the final reconstructed image. The key concept consists in introducing a relative motion between the collimator and the detector. Moreover, this design could also be incorporated into most commercially available gamma camera devices, without any excessive additional requirements. We use Monte Carlo simulations to assess the feasibility of such a device, analyze three possible designs and compare their sensitivity, resolution and uniformity. We propose a final design of a gamma camera with a high sensitivity ranging from 0.001 to 0.006 cps/Bq, and a high resolution of 0.5-1.0 cm (FWHM), for source-to-detector distances of 4-10 cm. Additionally, this planar gamma camera provides information about the depth of source (with approximate resolution of 1.5 cm) and excellent image uniformity.


Assuntos
Câmaras gama , Tomografia Computadorizada de Emissão de Fóton Único , Artefatos , Estudos de Viabilidade , Humanos , Método de Monte Carlo , Imagens de Fantasmas
4.
Artigo em Japonês | MEDLINE | ID: mdl-34148900

RESUMO

PURPOSE: The aim of this study was to evaluate the classification accuracy of specific blood flow reduction patterns in clinical images by deep learning using simulation data. METHODS: We obtained Z-score maps for 100 cases each of simulated Alzheimer's disease (AD), simulated dementia with Lewy bodies (DLB), and simulated normal cognition (NC) by performing statistical analysis of the simulation data that provided defects and healthy patient data. The clinical images were determined by reference to radiological reports, and Z-score maps of AD (n=33), DLB (n=20), and NC (n=28) were used. A network was constructed with reference to AlexNet, 4-fold cross-validation was performed using only simulation data, and classification accuracy was evaluated. We also trained the model using the simulation data and classified the clinical images. RESULTS: The accuracy rate of classification between simulations was 96.2% and that of the clinical images was 84.2%. CONCLUSION: Through deep learning using simulation data, clinical images may be classified with an accuracy of 84.2%.


Assuntos
Doença de Alzheimer , Aprendizado Profundo , Doença por Corpos de Lewy , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Diagnóstico Diferencial , Humanos , Doença por Corpos de Lewy/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único
5.
Int J Mol Sci ; 22(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073992

RESUMO

Angiogenesis is an active process, regulating new vessel growth, and is crucial for the survival and growth of tumours next to other complex factors in the tumour microenvironment. We present possible molecular imaging approaches for tumour vascularisation and vitality, focusing on radiopharmaceuticals (tracers). Molecular imaging in general has become an integrated part of cancer therapy, by bringing relevant insights on tumour angiogenic status. After a structured PubMed search, the resulting publication list was screened for oncology related publications in animals and humans, disregarding any cardiovascular findings. The tracers identified can be subdivided into direct targeting of angiogenesis (i.e., vascular endothelial growth factor, laminin, and fibronectin) and indirect targeting (i.e., glucose metabolism, hypoxia, and matrix metallo-proteases, PSMA). Presenting pre-clinical and clinical data of most tracers proposed in the literature, the indirect targeting agents are not 1:1 correlated with angiogenesis factors but do have a strong prognostic power in a clinical setting, while direct targeting agents show most potential and specificity for assessing tumour vascularisation and vitality. Within the direct agents, the combination of multiple targeting tracers into one agent (multimers) seems most promising. This review demonstrates the present clinical applicability of indirect agents, but also the need for more extensive research in the field of direct targeting of angiogenesis in oncology. Although there is currently no direct tracer that can be singled out, the RGD tracer family seems to show the highest potential therefore we expect one of them to enter the clinical routine.


Assuntos
Oncologia/métodos , Imagem Molecular/métodos , Neoplasias/diagnóstico por imagem , Neovascularização Patológica/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Animais , Biomarcadores Tumorais/metabolismo , Hipóxia Celular , Glucose/metabolismo , Humanos , Integrinas/metabolismo , Metaloproteinases da Matriz/metabolismo , Oncologia/instrumentação , Neoplasias/patologia , Neovascularização Patológica/patologia , Oligopeptídeos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
BMC Psychiatry ; 21(1): 289, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34082747

RESUMO

BACKGROUND: Parkinsonian symptoms are common adverse effects of antipsychotics. Older adults are particularly vulnerable to drug-induced parkinsonism. Nonetheless, parkinsonian symptoms in seniors treated with antipsychotics cannot be straightforwardly attributed to antipsychotic medication. A comprehensive diagnostic workup is necessary in many cases in order to shed light on the cause of such symptoms in this patient population. CASE SERIES: Eight cases of hospitalized depressed older adults with parkinsonian symptoms, who were treated for at least one year with antipsychotics, are reported. Based on neurological consultation, structural brain imaging and Ioflupane (I-123) dopamine transporter (DAT) single photon emission computerized tomography (SPECT), Parkinson's disease was diagnosed in one case, idiopathic tremor in another, vascular parkinsonism in another one, while in another individual parkinsonian symptoms persisted at 12-month post-discharge follow-up even though his/her symptoms were classified as drug-induced on discharge. In four patients, parkinsonian symptoms were definitely drug-induced and no movement disturbances were reported at follow-up. CONCLUSIONS: Differences in the cause and outcome of parkinsonian symptoms in seniors treated with antipsychotics merit systematic and in-depth study considering the therapeutic and prognostic implications of an accurate detection of the cause of such symptoms. Familiarizing clinical psychiatrists with these differences could pave the way towards approaching seniors with severe, atypical and/or persistent parkinsonian symptoms in a more individualized diagnostic and therapeutic manner, and towards more cautious prescribing of antipsychotics in this age group.


Assuntos
Antipsicóticos , Transtornos Parkinsonianos , Assistência ao Convalescente , Idoso , Antipsicóticos/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/tratamento farmacológico , Alta do Paciente , Tomografia Computadorizada de Emissão de Fóton Único
7.
Epilepsy Behav ; 121(Pt A): 108074, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34062446

RESUMO

OBJECTIVE: We evaluated SISCOM patterns and their relationship with surgical outcome in children with temporal lobe epilepsy (TLE) who had undergone a temporal lobe surgery. METHODS: This was an observational study evaluating SISCOM patterns in 40 children with TLE. We classified SISCOM patterns into 4 categories; (i) unilateral anteromesial and/or anterolateral temporal pattern; (ii) unilateral anteromesial and/or anterolateral temporal plus posterior extension pattern; (iii) bilateral anteromesial and/or anterolateral temporal pattern; and (iv) atypical pattern. Determinants of SISCOM pattern and correlation between postoperative outcomes and SISCOM patterns were evaluated. RESULTS: Pattern (i), (ii), (iii), and (iv) were identified in 10 (25%), 14 (35%), 0 (0%), and 16 (40%) patients, respectively. There was no significant correlation between patterns and postoperative outcomes. SISCOM patterns significantly associated with the presence of hippocampal sclerosis and type of focal cortical dysplasia (p-value = 0.048 and 0.036, respectively). Patients with HS had 5 times the odds of having unilateral temporal pattern, compared to patients with other neuropathology (OR = 5, 95% CI 0.92 to 27.08). Patients with FCD type 2 had 9.71 times the odds of having atypical pattern, compared to patients with other types of FCD (OR = 9.71, 95% CI 0.92 to 103.04). Lobar concordance of SISCOM and ictal and interictal scalp EEG significantly correlated with postoperative outcomes (p-value = 0.018 and 0.013, respectively). CONCLUSION: Three SISCOM patterns were seen. Patients with HS had increased odds of having unilateral temporal pattern while patients with FCD type 2 had increased odds of having atypical pattern. However, there was no significant correlation between SISCOM patterns and postoperative outcomes. Lobar concordance of SISCOM and ictal and interictal scalp EEG significantly correlated with postoperative outcome. SIGNIFICANCE: This study shows that the distribution of SISCOM patterns and their relationship with postoperative outcomes in children with TLE are different from adult population. Besides, SISCOM may add only limited diagnostic and prognostic information in children with drug-resistant TLE undergoing epilepsy surgery. Further evaluation to identify patient populations that may benefit from SISCOM is desirable.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia do Lobo Temporal , Adulto , Criança , Eletroencefalografia , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Tomografia Computadorizada de Emissão de Fóton Único
8.
Molecules ; 26(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070537

RESUMO

INTRODUCTION: Radiotracers are widely used in medical imaging, using techniques of gamma-camera imaging (scintigraphy and SPECT) or positron emission tomography (PET). In bone marrow infection, there is no single routine test available that can detect infection with sufficiently high diagnostic accuracy. Here, we review radiotracers used for imaging of bone marrow infection, also known as osteomyelitis, with a focus on why these molecules are relevant for the task, based on their physiological uptake mechanisms. The review comprises [67Ga]Ga-citrate, radiolabelled leukocytes, radiolabelled nanocolloids (bone marrow) and radiolabelled phosphonates (bone structure), and [18F]FDG as established radiotracers for bone marrow infection imaging. Tracers that are under development or testing for this purpose include [68Ga]Ga-citrate, [18F]FDG, [18F]FDS and other non-glucose sugar analogues, [15O]water, [11C]methionine, [11C]donepezil, [99mTc]Tc-IL-8, [68Ga]Ga-Siglec-9, phage-display selected peptides, and the antimicrobial peptide [99mTc]Tc-UBI29-41 or [68Ga]Ga-NOTA-UBI29-41. CONCLUSION: Molecular radiotracers allow studies of physiological processes such as infection. None of the reviewed molecules are ideal for the imaging of infections, whether bone marrow or otherwise, but each can give information about a separate aspect such as physiology or biochemistry. Knowledge of uptake mechanisms, pitfalls, and challenges is useful in both the use and development of medically relevant radioactive tracers.


Assuntos
Medula Óssea/patologia , Compostos Radiofarmacêuticos/química , Humanos , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
9.
Medicine (Baltimore) ; 100(26): e26534, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34190190

RESUMO

ABSTRACT: Many previous studies have estimated the rate of dopaminergic denervation in Parkinson disease (PD) via imaging studies. However, they lack the considerations of onset age, disease duration at onset, gender, and dopaminergic denervation due to normal aging. Herein, using a large prospective cohort, we estimated the rate of dopaminergic denervation in PD patients, compared with an age- and gender-matched normal control group.One hundred forty-one normal controls and 301 PD patients were enrolled. Striatal specific binding ratios (SBRs) of I-123 FP-CIT single positron emission tomography images were analyzed according to the age of onset, gender, and the duration of motor symptoms.In the PD group, symptom duration was significantly correlated with caudate SBRs, but with putamen SBRs (P  < .05, R2 = 0.02). Moreover, was significantly inversely related to caudate SBRs, but not with putamen SBRs (P  < .05, R2 = 0.02). Patients of different age onsets did not show any significant correlation between symptom durations and striatal SBRs. In the age-matched group, no significant relationship was observed between symptom duration and percent decrease of caudate SBRs, but there was a significant relationship between symptom duration and percent decrease of the putamen SBRs (P  < .01, R2 = 0.06). There was no significant relationship between the symptom duration and the percent decrease of striatal SBRs in the age- and gender-matched group.The significance and R2 values from the regression analysis between symptom duration, age, and dopaminergic denervation are low. This suggests that, contrary to previous knowledge, there is a relatively weak association between dopaminergic denervation and age or symptom duration.


Assuntos
Corpo Estriado , Diagnóstico por Imagem , Dopamina/metabolismo , Neurônios Dopaminérgicos , Degeneração Neural , Doença de Parkinson , Idade de Início , Biomarcadores/análise , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/metabolismo , Diagnóstico por Imagem/classificação , Diagnóstico por Imagem/métodos , Diagnóstico por Imagem/estatística & dados numéricos , Progressão da Doença , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Degeneração Neural/diagnóstico , Degeneração Neural/fisiopatologia , Doença de Parkinson/diagnóstico , Doença de Parkinson/epidemiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/fisiopatologia , Gravidade do Paciente , República da Coreia/epidemiologia , Avaliação de Sintomas/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
10.
Internist (Berl) ; 62(7): 729-740, 2021 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-34106293

RESUMO

Myocardial ischemia is triggered by a mismatch between the oxygen supply and demand of the myocardial tissue. The most common cause is coronary artery disease; however, not every coronary stenosis is hemodynamically relevant and leads to myocardial ischemia. The guidelines recommend noninvasive ischemia diagnostics prior to invasive treatment in patients with chronic coronary syndrome. Cardiac computed tomography, stress echocardiography, nuclear cardiological procedures (positron emission tomography and single photon emission computed tomography) and cardiac magnetic resonance imaging are the main diagnostic tools for this purpose and are incorporated into the clinical routine. This article provides a review of the indications, the relative advantages and disadvantages of the respective methods and their utilization in routine clinical practice.


Assuntos
Doença da Artéria Coronariana , Tomografia Computadorizada de Emissão de Fóton Único , Angiografia Coronária , Coração , Humanos , Isquemia
11.
Brain Nerve ; 73(6): 725-730, 2021 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-34127568

RESUMO

Neuroimaging is the most important tool to treat epileptic foci. Preoperative detection of underlying structural lesions increases the likelihood of the successful surgical treatment of drug-resistant epilepsy. Imaging studies used for preoperative focal determination include morphological imaging modalities, such as computed tomography and magnetic resonance imaging, and functional ones, such as positron emission tomography and single photon-emission computed tomography. The keys to diagnostic imaging in epilepsy are appropriate protocols and extensive knowledge to make comprehensive decisions. This article comprehensively overviews neuroimaging techniques used in epilepsy.


Assuntos
Epilepsia , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada de Emissão de Fóton Único
12.
Medicine (Baltimore) ; 100(20): e25928, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34011065

RESUMO

ABSTRACT: Bilateral kidney damage in hypertensive patients is not parallel. Angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACEI/ARB), as a commonly used antihypertensive drug, could protect kidney function and delay its deterioration. Most studies focused on overall renal function, but the researches on split renal function (SRF) are rare. We investigated the effects of ACEI/ARB on the SRF in patients with primary hypertension.Patients with primary hypertension (n = 429; male: 213; female: 216) admitted to our department between January 2014 and December 2016 were included in this study. The glomerular filtration rate (GFR) of split and total renal function were determined using diethylenetriaminepentaacetic acid tagged with 99mTc renal dynamic imaging method. For the same patient, the side with high GFR was considered as higher GFR kidney, whereas that with a low GFR was considered as lower GFR kidney. The split function score (Q value) was utilized to evaluate the differences of bilateral renal function. The patients were divided into 3 groups based on the Q values (Group 1, Q value <5%; Group 2, Q value of 5%-10%; Group 3, Q value ≥10%). All the patients received antihypertensive therapy based on ACEI/ARB. The renal dynamic imaging was performed in the 1-year follow-up to investigate the changes of the SRF.Compared with the baseline level, significant decline was noticed in the serum creatinine (Scr) in Group 2 and Group 3 (P < .05). The cystatin C in Group 3 showed significant decline (P < .05). Compared with the baseline, there was significant decline in the Q value in Group 2, whereas the GFR of lower GFR kidney showed significant increase (P < .05). No statistical differences were noticed in the Q value and split GFR in Group 1 and Group 3 (P > .05).In primary hypertension patients, ACEI/ARB therapy could improve the SRF of lower GFR kidney in the presence of certain differences between the SRF. As a result, the SRF difference was reduced. In case of Q value in a range of 5% to 10%, ACEI/ARB could improve the renal function effectively. It may be significant for the design of antihypertensive drugs.


Assuntos
Antagonistas de Receptores de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Hipertensão/tratamento farmacológico , Rim/efeitos dos fármacos , Insuficiência Renal/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste/administração & dosagem , Creatinina/sangue , Cistatina C/sangue , Feminino , Seguimentos , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/fisiologia , Humanos , Hipertensão/sangue , Hipertensão/complicações , Rim/diagnóstico por imagem , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Insuficiência Renal/sangue , Insuficiência Renal/diagnóstico , Insuficiência Renal/etiologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Resultado do Tratamento
13.
J Neurol Sci ; 426: 117476, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33975190

RESUMO

INTRODUCTION: Although functional imaging is useful for the diagnosis and pathophysiological evaluation of Parkinson's disease (PD), little is known about the relationship between functional imaging findings and PD clinical features. The objective of this study was to determine the relationship between 123I-FP-CIT-SPECT findings and motor symptoms, in particular gait disturbance. METHODS: The study included 46 drug-naive patients with early-stage PD. The specific binding ratios (SBRs) in the striatum and its subregions, namely anterior/posterior putamen and caudate nucleus, were calculated in patients who underwent 123I-FP-CIT-SPECT. Motor symptoms were evaluated using the modified Hoehn and Yahr (HY) stage and the Unified Parkinson's Disease Rating Scale (UPDRS) part III. Gait disturbance was evaluated by the mean gait cycle duration and the mean gait acceleration amplitude measured with a wearable sensor. RESULTS: The mean SBRs of the striatum and anterior putamen were significantly associated with the modified HY stage and UPDRS part III score. The mean SBR of the caudate nucleus was significantly associated with the UPDRS part III score. The mean striatal SBR was also significantly associated with the mean gait cycle duration and mean gait acceleration amplitude. CONCLUSION: The mean striatal SBR, as determined by 123I-FP-CIT-SPECT, was significantly associated with motor severity and gait severity in drug-naive patients with PD.


Assuntos
Doença de Parkinson , Preparações Farmacêuticas , Proteínas da Membrana Plasmática de Transporte de Dopamina , Humanos , Radioisótopos do Iodo , Doença de Parkinson/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tropanos
14.
BMJ Case Rep ; 14(5)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33962918

RESUMO

Pterin species participate in dopamine biosynthesis, and abnormal pteridine metabolism contributes to reduced dopamine. GTP cyclohydrolase 1 (GCH-1) deficiency, which triggers pteridine hypometabolism and normally develops in childhood, can mediate an adult-onset decrease in levodopa production and dopa-responsive dystonia (DRD), with normal dopamine transporter single-photon emission computed tomography (DAT-SPECT). A recent study described normal DAT-SPECT in adult-onset cases with GCH-1 mutations, clinically diagnosed with Parkinson's disease, which raises the possibility that the abnormal metabolism of pteridine may be a differential diagnosis for adult-onset parkinsonism. We report an older patient with levodopa-responsive parkinsonism with normal DAT-SPECT, or scans without evidence of dopamine deficit (SWEDD), whose biochemical analysis showed pterin hypometabolism, which occurs in GCH-1-deficient DRD. Surprisingly, this patient presented no dystonia or GCH-1 gene mutation or deletion. This case suggests that low pterin metabolism should be considered in older-onset levodopa-responsive parkinsonism with normal DAT-SPECT, even without GCH-1 mutations or deletions.


Assuntos
Levodopa , Transtornos Parkinsonianos , Adulto , Idoso , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , GTP Cicloidrolase , Humanos , Levodopa/uso terapêutico , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/tratamento farmacológico , Pterinas , Tomografia Computadorizada de Emissão de Fóton Único
16.
Radiother Oncol ; 160: 120-124, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33964328

RESUMO

This study investigates agreement between ventilation and perfusion for lung cancer patients undergoing radiotherapy. Ventilation-perfusion scans of nineteen patients with stage III lung cancer from a prospective protocol were compared using voxel-wise Spearman correlation-coefficients. The presented results show in about 25% of patients, ventilation and perfusion exhibit lower agreement.


Assuntos
Tomografia Computadorizada Quadridimensional , Neoplasias Pulmonares , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Perfusão , Estudos Prospectivos , Ventilação Pulmonar , Tomografia Computadorizada de Emissão de Fóton Único
17.
Sleep Med ; 83: 132-144, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33993030

RESUMO

Abnormal motor manifestations in REM sleep are the most visible feature of idiopathic REM sleep behavior disorder (iRBD), which precedes the overt alpha-synucleinopathy. The aim of this study was to perform a systematic visual analysis of the motor events (ME) captured during video-polysomnography, and clarify their relation to the disease severity. Thirty-four iRBD patients (5 women, 29 men; age 67.7 ± 7.2) with a mean follow-up duration 2.9 ± 1.1 years. and 33 controls (10 women, 23 men; age 61.5 ± 8.2) were examined. The ME captured during REM sleep were classified into four categories, previously defined by Frauscher et al. according to clinical severity: minor/simple jerks, major, complex and violent. An average frequency of 110.8 ± 75.2 ME per hour were identified in iRBD, 7.5 ± 11.6 in the controls (p < 0.001). Of these ME, 68.4% were classified as minor/simple jerks, 9.3% as major, 21.7% as complex and 0.7% as violent. The ME frequency was negatively associated with tracer binding on dopamine transporter single-photon emission computed tomography (DAT-SPECT); the association was stronger for caudate nucleus compared to putamen. During follow-up seven patients (24.1%) phenoconverted, yielding a yearly phenoconversion rate 8.3%. Violent ME were associated with increased hazard ratio for phenoconversion in frequency (p = 0.012) and total duration (p = 0.007). Patients with higher amounts of violent ME had a greater risk of phenoconversion; therefore, their role as a predictor should be considered. Additionally, ME were associated with nigrostriatal degeneration, according to DAT-SPECT. These findings indicate that the degree of the clinical severity of motor manifestations in iRBD reflects the severity of the disease.


Assuntos
Transtorno do Comportamento do Sono REM , Idoso , Proteínas da Membrana Plasmática de Transporte de Dopamina , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Transtorno do Comportamento do Sono REM/diagnóstico por imagem , Sono REM , Tomografia Computadorizada de Emissão de Fóton Único
18.
Neurology ; 97(1): e88-e102, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-33980708

RESUMO

OBJECTIVE: To determine relative frequencies and linguistic profiles of primary progressive aphasia (PPA) variants associated with GRN (progranulin) mutations and to study their neuroanatomic correlates. METHODS: Patients with PPA carrying GRN mutations (PPA-GRN) were selected among a national prospective research cohort of 1,696 patients with frontotemporal dementia, including 235 patients with PPA. All patients with amyloid-positive CSF biomarkers were excluded. In this cross-sectional study, speech/language and cognitive profiles were characterized with standardized evaluations, and gray matter (GM) atrophy patterns using voxel-based morphometry. Comparisons were performed with controls and patients with sporadic PPA. RESULTS: Among the 235 patients with PPA, 45 (19%) carried GRN mutations, and we studied 32 of these. We showed that logopenic PPA (lvPPA) was the most frequent linguistic variant (n = 13, 41%), followed by nonfluent/agrammatic (nfvPPA; n = 9, 28%) and mixed forms (n = 8, 25%). Semantic variant was rather rare (n = 2, 6%). Patients with lvPPA, qualified as nonamyloid lvPPA, presented canonical logopenic deficit. Seven of 13 had a pure form; 6 showed subtle additional linguistic deficits not fitting criteria for mixed PPA and hence were labeled as logopenic-spectrum variant. GM atrophy involved primarily left posterior temporal gyrus, mirroring neuroanatomic changes of amyloid-positive-lvPPA. Patients with nfvPPA presented agrammatism (89%) rather than apraxia of speech (11%). CONCLUSIONS: This study shows that the most frequent PPA variant associated with GRN mutations is nonamyloid lvPPA, preceding nfvPPA and mixed forms, and illustrates that the language network may be affected at different levels. GRN testing is indicated for patients with PPA, whether familial or sporadic. This finding is important for upcoming GRN gene-specific therapies.


Assuntos
Afasia Primária Progressiva/genética , Progranulinas/genética , Idoso , Afasia Primária Progressiva/diagnóstico por imagem , Atrofia , Biomarcadores/líquido cefalorraquidiano , Estudos de Coortes , Estudos Transversais , Feminino , Demência Frontotemporal/diagnóstico por imagem , Demência Frontotemporal/genética , Frequência do Gene , Humanos , Testes de Linguagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Testes Neuropsicológicos , Estudos Prospectivos , Fala , Tomografia Computadorizada de Emissão de Fóton Único
19.
Psychogeriatrics ; 21(4): 618-626, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34056807

RESUMO

BACKGROUND: In early-stage amnestic mild cognitive impairment (aMCI), differences in the neuropsychological characteristics of each individual are subtle. We investigated differences in neuropsychological performance between aMCI patients with and without hypoperfusion in the medial parietal regions (MP). We further compared patients with hypoperfusion in the left and right lateral parietal regions. METHODS: We examined 165 aMCI patients (mean age: 76.8 ± 5.5 years; 87 women) who had undergone neuropsychological measurement and single-photon emission computed tomography. We classified participants into two subgroups with and without hypoperfusion: MP hypoperfusion (+) and MP hypoperfusion (-); classification was based on Z-scores (calculated by three-dimensional stereotactic surface projection technique) of three regions of interest in the parietal lobes (i.e. MP regions including posterior cingulate cortex and precuneus and left and right inferior parietal lobules (lateral parietal regions)). The MP hypoperfusion (-) group was classified into left lateral parietal hypoperfusion (+) and right lateral parietal hypoperfusion (+) subgroups. We performed either univariate or multivariate ancova to compare neuropsychological scores for continuous variables between groups and examined dichotomous variables using χ2 tests. RESULTS: In the overall aMCI sample, scores on logical memory delayed recall in the MP hypoperfusion (+) group were significantly lower than those in the MP hypoperfusion (-) group. Total scores on Rey-Osterrieth Complex Figure Test delayed recall were also marginally lower in the MP hypoperfusion (+) group than in the MP hypoperfusion (-) group. Comparisons of neuropsychological test scores between the left and right lateral parietal hypoperfusion (+) groups revealed no significant differences. CONCLUSIONS: The present findings suggest that MP hypoperfusion (+) is associated with more robust memory deficits than MP hypoperfusion (-). Combining neuropsychological tests and single-photon emission computed tomography findings may be useful for early detection of cognitive decline in aMCI.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Idoso , Idoso de 80 Anos ou mais , Encéfalo , Feminino , Humanos , Transtornos da Memória , Rememoração Mental , Testes Neuropsicológicos , Tomografia Computadorizada de Emissão de Fóton Único
20.
Phys Med ; 85: 24-31, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33957577

RESUMO

PURPOSE: Patient-specific dosimetry in MRT relies on quantitative imaging, pharmacokinetic assessment and absorbed dose calculation. The DosiTest project was initiated to evaluate the uncertainties associated with each step of the clinical dosimetry workflow through a virtual multicentric clinical trial. This work presents the generation of simulated clinical SPECT datasets based on GATE Monte Carlo modelling with its corresponding experimental CT image, which can subsequently be processed by commercial image workstations. METHODS: This study considers a therapy cycle of 6.85 GBq 177Lu-labelled DOTATATE derived from an IAEA-Coordinated Research Project (E23005) on "Dosimetry in Radiopharmaceutical therapy for personalised patient treatment". Patient images were acquired on a GE Infinia-Hawkeye 4 gamma camera using a medium energy (ME) collimator. Simulated SPECT projections were generated based on experimental time points and validated against experimental SPECT projections using flattened profiles and gamma index. The simulated projections were then incorporated into the patient SPECT/CT DICOM envelopes for processing and their reconstruction within a commercial image workstation. RESULTS: Gamma index passing rate (2% - 1 pixel criteria) between 95 and 98% and average gamma between 0.28 and 0.35 among different time points revealed high similarity between simulated and experimental images. Image reconstruction of the simulated projections was successful on HERMES and Xeleris workstations, a major step forward for the initiation of a multicentric virtual clinical dosimetry trial based on simulated SPECT/CT images. CONCLUSIONS: Realistic 177Lu patient SPECT projections were generated in GATE. These modelled datasets will be circulated to different clinical departments to perform dosimetry in order to assess the uncertainties in the entire dosimetric chain.


Assuntos
Radiometria , Tomografia Computadorizada de Emissão de Fóton Único , Câmaras gama , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único
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