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1.
Eur Radiol ; 34(1): 422-432, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37566266

RESUMO

OBJECTIVES: In this study, we developed a radiomic signature for the classification of benign lipid-poor adenomas, which may potentially help clinicians limit the number of unnecessary investigations in clinical practice. Indeterminate adrenal lesions of benign and malignant nature may exhibit different values of key radiomics features. METHODS: Patients who had available histopathology reports and a non-contrast-enhanced CT scan were included in the study. Radiomics feature extraction was done after the adrenal lesions were contoured. The primary feature selection and prediction performance scores were calculated using the least absolute shrinkage and selection operator (LASSO). To eliminate redundancy, the best-performing features were further examined using the Pearson correlation coefficient, and new predictive models were created. RESULTS: This investigation covered 50 lesions in 48 patients. After LASSO-based radiomics feature selection, the test dataset's 30 iterations of logistic regression models produced an average performance of 0.72. The model with the best performance, made up of 13 radiomics features, had an AUC of 0.99 in the training phase and 1.00 in the test phase. The number of features was lowered to 5 after performing Pearson's correlation to prevent overfitting. The final radiomic signature trained a number of machine learning classifiers, with an average AUC of 0.93. CONCLUSIONS: Including more radiomics features in the identification of adenomas may improve the accuracy of NECT and reduce the need for additional imaging procedures and clinical workup, according to this and other recent radiomics studies that have clear points of contact with current clinical practice. CLINICAL RELEVANCE STATEMENT: The study developed a radiomic signature using unenhanced CT scans for classifying lipid-poor adenomas, potentially reducing unnecessary investigations that scored a final accuracy of 93%. KEY POINTS: • Radiomics has potential for differentiating lipid-poor adenomas and avoiding unnecessary further investigations. • Quadratic mean, strength, maximum 3D diameter, volume density, and area density are promising predictors for adenomas. • Radiomics models reach high performance with average AUC of 0.95 in the training phase and 0.72 in the test phase.


Assuntos
Adenoma Adrenocortical , Radiômica , Humanos , Benchmarking , Tomografia Computadorizada por Raios X , Lipídeos , Estudos Retrospectivos
2.
MAGMA ; 37(1): 93-100, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38019376

RESUMO

OBJECTIVE: We established normal ranges for native T1 and T2 values in the human liver using a 1.5 T whole-body imager (General Electric) and we evaluated their variation across hepatic segments and their association with age and sex. MATERIALS AND METHODS: One-hundred healthy volunteers aged 20-70 years (50% females) underwent MRI. Modified Look-Locker inversion recovery and multi-echo fast-spin-echo sequences were used to measure hepatic native global and segmental T1 and T2 values, respectively. RESULTS: T1 and T2 values exhibited good intra- and inter-observer reproducibility (coefficient of variation < 5%). T1 value over segment 4 was significantly lower than the T1 values over segments 2 and 3 (p < 0.0001). No significant regional T2 variability was detected. Segmental and global T1 values were not associated with age or sex. Global T2 values were independent from age but were significantly lower in males than in females. The lower and upper limits of normal for global T1 values were, respectively, 442 ms and 705 ms. The normal range for global T2 values was 35 ms-54 ms in males and 39 ms-54 ms in females. DISCUSSION: Liver T1 and T2 mapping is feasible and reproducible and the provided normal ranges may help to establish diagnosis and progression of various liver diseases.


Assuntos
Fígado , Imageamento por Ressonância Magnética , Masculino , Feminino , Humanos , Valores de Referência , Voluntários Saudáveis , Reprodutibilidade dos Testes , Wortmanina , Valor Preditivo dos Testes , Fígado/diagnóstico por imagem
3.
Radiol Med ; 129(3): 488-496, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38353863

RESUMO

PURPOSE: Dual-energy X-ray absorptiometry (DXA) is the gold standard for measuring bone mineral density (BMD) with tolerable error rate, high precision, and excellent consistency. Our objective was to investigate the frequency and distribution of errors in a cohort of patients with Thalassemia major (TM). METHODS: We reviewed the DXA examinations of 340 patients with ß-TM followed by our institution, acquired in different imaging centers between 2009 and 2019. We collected sex and age at the time of the first examination and at the last visit, as well as BMD, T-score, and Z-score values. Errors were analyzed by anatomical site (lumbar spine, total hip, femoral neck). RESULTS: Out of 5099 total DXA scans, 11.85% presented one or more errors. Specifically, the incorrect examinations were 315 out of 1707 (18.45%) at the lumbar spine level, 113 out of 1697 (6.66%) at the total hip, 176 out of 1695 (10.38%) at the femoral neck. Errors in vertebral inclusion were the most frequently registered (45.86%). A significant difference resulted from the comparison of the T-score and Z-score median values of all the lumbar spine DXA examinations and the correct ones (p value 0.037 and 0.0003, respectively). CONCLUSION: Although not directly involved in the performance and interpretation of DXA, physicians interested in osteoporosis management should be familiar with the protocols to minimize errors and allow the proper use of bone densitometry. DXA obtained at the spine level is more frequently affected by errors in patients with TM, potentially influencing the diagnostic assessment of bone health status.


Assuntos
Talassemia beta , Humanos , Seguimentos , Talassemia beta/diagnóstico por imagem , Densidade Óssea , Absorciometria de Fóton/métodos , Vértebras Lombares/diagnóstico por imagem
4.
Int J Mol Sci ; 24(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36834877

RESUMO

Magnetic resonance imaging (MRI) is a non-invasive powerful modern clinical technique that is extensively used for the high-resolution imaging of soft tissues. To obtain high-definition pictures of tissues or of the whole organism this technique is enhanced by the use of contrast agents. Gadolinium-based contrast agents have an excellent safety profile. However, over the last two decades, some specific concerns have surfaced. Mn(II) has different favorable physicochemical characteristics and a good toxicity profile, which makes it a good alternative to the Gd(III)-based MRI contrast agents currently used in clinics. Mn(II)-disubstituted symmetrical complexes containing dithiocarbamates ligands were prepared under a nitrogen atmosphere. The magnetic measurements on Mn complexes were carried out with MRI phantom measurements at 1.5 T with a clinical magnetic resonance. Relaxivity values, contrast, and stability were evaluated by appropriate sequences. Studies conducted to evaluate the properties of paramagnetic imaging in water using a clinical magnetic resonance showed that the contrast, produced by the complex [Mn(II)(L')2] × 2H2O (L' = 1.4-dioxa-8-azaspiro[4.5]decane-8-carbodithioate), is comparable to that produced by gadolinium complexes currently used in medicine as a paramagnetic contrast agent.


Assuntos
Meios de Contraste , Manganês , Manganês/química , Meios de Contraste/química , Gadolínio/química , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética
5.
Eur J Haematol ; 109(6): 648-655, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36000276

RESUMO

OBJECTIVE: Dual-energy X-ray absorptiometry (DXA) remains the cornerstone for osteoporosis evaluation in Thalassemia major. However, several drawbacks have been observed in this unique setting. We sought to determine the correlation between quantitative CT (QCT) and DXA-derived parameters; secondarily, we aimed to investigate the role of the two techniques in predicting the risk of fracture. METHODS: We retrospectively included patients with ß-thalassemia major who had undergone both lumbar and femoral DXA examinations, and CT scans including the lumbar spine, performed for disparate diagnostic issues, within 4 months from the DXA. CT data were examined employing a phantom-less QCT method for bone mineral density (BMD) assessment. We also retrieved any spontaneous or fragility fractures occurring from 1 year before up to 5 years after the date of DXA scans. RESULTS: The 43 patients were included. QCT measures were significantly higher than those determined by DXA. The gap between QCT and DXA values was strongly associated with patient age. The most powerful predictive variable for risk of fracture was the ACR classification based on volumetric BMD obtained by QCT. CONCLUSIONS: DXA provided more negative measures than those determined by QCT. However, QCT seemed to evaluate thalassaemic osteopathy better than DXA, since volumetric BMD was a stronger predictor of fracture.


Assuntos
Fraturas Ósseas , Osteoporose , Talassemia beta , Humanos , Talassemia beta/diagnóstico , Talassemia beta/diagnóstico por imagem , Estudos Retrospectivos , Absorciometria de Fóton/métodos , Densidade Óssea , Osteoporose/diagnóstico por imagem , Osteoporose/etiologia , Tomografia Computadorizada por Raios X/métodos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/etiologia
6.
Molecules ; 27(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35208982

RESUMO

The favorable nuclear properties in combination with the rich coordination chemistry make technetium-99m the radioisotope of choice for the development of myocardial perfusion tracers. In the early 1980s, [99mTc]Tc-Sestamibi, [99mTc]Tc-Tetrofosmin, and [99mTc]Tc-Teboroxime were approved as commercial radiopharmaceuticals for myocardial perfusion imaging in nuclear cardiology. Despite its peculiar properties, the clinical use of [99mTc]Tc-Teboroxime was quickly abandoned due to its rapid myocardial washout. Despite their widespread clinical applications, both [99mTc]Tc-Sestamibi and [99mTc]Tc-Tetrofosmin do not meet the requirements of an ideal perfusion imaging agent due to their relatively low first-pass extraction fraction and high liver absorption. An ideal radiotracer for myocardial perfusion imaging should have a high myocardial uptake; a high and stable target-to-background ratio with low uptake in the lungs, liver, stomach during the image acquisition period; a high first-pass myocardial extraction fraction and very rapid blood clearance; and a linear relationship between radiotracer myocardial uptake and coronary blood flow. Although it is difficult to reconcile all these properties in a single tracer, scientific research in the field has always channeled its efforts in the development of molecules that are able to meet the characteristics of ideality as much as possible. This short review summarizes the developments in 99mTc myocardial perfusion tracers, which are able to fulfill hitherto unmet medical needs and serve a large population of patients with heart disease, and underlines their strengths and weaknesses, the lost and found opportunities thanks to the developments of the new ultrafast SPECT technologies.


Assuntos
Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca , Imagem de Perfusão do Miocárdio , Miocárdio , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Humanos , Compostos de Organotecnécio/química , Compostos de Organotecnécio/farmacocinética , Compostos de Organotecnécio/uso terapêutico , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/uso terapêutico
7.
Molecules ; 27(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36014521

RESUMO

In recent decades, the use of alpha; pure beta; or beta/gamma emitters in oncology, endocrinology, and interventional cardiology rheumatology, has proved to be an important alternative to the most common therapeutic regimens. Among radionuclides used for therapy in nuclear medicine, two rhenium radioisotopes are of particular relevance: rhenium-186 and rhenium-188. The first is routinely produced in nuclear reactors by direct neutron activation of rhenium-186 via 185Re(n,γ)186Re nuclear reaction. Rhenium-188 is produced by the decay of the parent tungsten-188. Separation of rhenium-188 is mainly performed using a chromatographic 188W/188Re generator in which tungsten-188 is adsorbed on the alumina column, similar to the 99Mo/99mTc generator system, and the radionuclide eluted in saline solution. The application of rhenium-186 and rhenium-188 depends on their specific activity. Rhenium-186 is produced in low specific activity and is mainly used for labeling particles or diphosphonates for bone pain palliation. Whereas, rhenium-188 of high specific activity can be used for labeling peptides or bioactive molecules. One of the advantages of rhenium is its chemical similarity with technetium. So, diagnostic technetium analogs labeled with radiorhenium can be developed for therapeutic applications. Clinical trials promoting the use of 186/188Re-radiopharmaceuticals is, in particular, are discussed.


Assuntos
Medicina Nuclear , Rênio , Medicina Nuclear/métodos , Radioisótopos/química , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/uso terapêutico , Rênio/química , Rênio/uso terapêutico , Tecnécio
8.
Am J Phys Anthropol ; 175(4): 847-864, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33973654

RESUMO

OBJECTIVES: Palate morphology is constantly changing throughout an individual's lifespan, yet its asymmetry during growth is still little understood. In this research, we focus on the study of palate morphology by using 3D geometric morphometric approaches to observe changes at different stages of life, and to quantify the impact of directional and fluctuating asymmetry on different areas at different growth stages. MATERIALS AND METHODS: The sample consists of 183 individuals (1-72 years) from two identified human skeletal collections of 19th and early 20th Century Italian contexts. A 3D-template of 41 (semi)landmarks was applied on digital palate models to observe morphological variation during growth. RESULTS: Asymmetrical components of the morphological structure appears multidirectional on the entire palate surface in individuals <2 years old and become oriented (opposite bilateral direction) between 2 and 6 years of age. Specifically, directional asymmetry differentially impacts palate morphology at different stages of growth. Both the anterior and posterior palate are affected by mild alterations in the first year of life, while between 2 and 6 years asymmetry is segregated in the anterior area, and moderate asymmetry affects the entire palatal surface up to 12 years of age. Our results show that stability of the masticatory system seems to be reached around 13-35 years first by females and then males. From 36 years on both sexes show similar asymmetry on the anterior area. Regarding fluctuating asymmetry, inter-individual variability is mostly visible up to 12 years of age, after which only directional trends can be clearly observed at a group level. DISCUSSION: Morphological structure appears instable during the first year of life and acquires an opposite asymmetric bilateral direction between 2 and 6 years of age. This condition has been also documented in adults; when paired with vertical alteration, anterior/posterior asymmetry seems to characterize palate morphology, which is probably due to mechanical factors during the lifespan. Fluctuating asymmetry is predominant in the first period of life due to a plausible relationship with the strength of morphological instability of the masticatory system. Directional asymmetry, on the other hand, shows that the patterning of group-level morphological change might be explained as a functional response to differential inputs (physiological forces, nutritive and non-nutritive habits, para-masticatory activity as well as the development of speech) in different growth stages. This research has implications with respect to medical and evolutionary fields. In medicine, palate morphology should be considered when planning orthodontic and surgical procedures as it could affect the outcome. As far as an evolutionary perspective is concerned the dominance of directional asymmetries in the masticatory system could provide information on dietary and cultural habits as well as pathological conditions in our ancestors.


Assuntos
Palato , Pré-Escolar , Feminino , Humanos , Masculino
9.
Eur J Nucl Med Mol Imaging ; 47(13): 3008-3017, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32430583

RESUMO

PURPOSE: Radioligand therapy (RLT) with 177Lu-PSMA-617 is a promising option for patients with metastatic castration-resistant prostate cancer (mCRPC). The present study was designed to define the safety and initial response to a minimal effective injected activity/cycle of 177Lu-PSMA-617 in mCRPC patients. New protective agents for salivary glands and kidney were co-administered and dosimetry was carried out. PATIENTS AND METHODS: A prospective single-arm, open label phase II study on mCRPC was activated at our institute in April 2017. Patients with histologically confirmed advanced mCRPC previously treated with standard life-prolonging agents were enrolled. Folic polyglutamate tablets were orally administered as parotid gland protectors and 500 mL of a 10% mannitol solution was intravenously infused to reduce kidney uptake before the injection of 3.7-5.5 GBq of 177Lu-PSMA-617 repeated four times at interval of 8 weeks. The adsorbed dose calculation was performed with MIRD formalism (OLINDA/EXM software). The Bryant and Day design was used to estimate the sample size taking account of both activity and toxicity. RESULTS: Forty-three eligible patients were evaluated for toxicity and initial response. Dosimetry was carried out in 13 patients. Two (4.8%) patients had G3 and 8 (19.5%) had G2 hematological toxicity. Only 3 (6.9%) patients had mild G1 salivary gland toxicity and 8 (19.5%) had G1 renal toxicity. A decrease of ≥ 30% in prostate-specific antigen (PSA) was achieved after the first cycle in 17 (40.5%) patients, of whom 13 had a PSA decline of >50% after the second cycle. The median adsorbed doses were 0.65 mGy/MBq (range 0.33-2.63) for parotid glands, 0.42 mGy/MBq (0.14-0.81) for kidneys, 0.036 mGy/MBq (0.023-0.067) for red marrow, and 0.038 mGy/MBq (0.018-0.135) for the whole body. CONCLUSION: In advanced, heavily pre-treated mCRPC patients, 3.7 GBq/cycle of 177Lu-PSMA-617 was safe and produced early biochemical and imaging responses at PSMA whole-body scan post injection. Dosimetry of salivary glands suggests that the co-administration of polyglutamate tablets may reduce salivary gland uptake. CLINICAL TRIAL REGISTRATION: EU Clinical Trials Register No.: 2016-002732-32; NCT03454750. Collection and assembly of data: April 2017 and February 2019.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Dipeptídeos/efeitos adversos , Compostos Heterocíclicos com 1 Anel/efeitos adversos , Humanos , Masculino , Glândula Parótida , Ácido Poliglutâmico/efeitos adversos , Estudos Prospectivos , Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração/radioterapia , Compostos Radiofarmacêuticos
10.
Aging Clin Exp Res ; 32(7): 1303-1308, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31471889

RESUMO

INTRODUCTION: The relationship between post-menopausal osteoporosis and obesity has been mainly investigated using bone mineral density (BMD) as marker of bone health. Since BMD does not reflect bone microarchitecture, another analytical tool, the Trabecular Bone Score (TBS), has been recently developed for this purpose. In this study, we intended to investigate the validity of TBS as marker of bone quality in obese post-menopausal women. METHODS AND MATERIALS: Three hundred fifty-two post-menopausal women were consecutively enrolled in the study and underwent anthropometric and dual-energy X-ray absorptiometry (DXA) examination. DXA-based BMD was used to classify subjects into osteoporotic (9%), osteopenic (58%), and controls (33%) categories. As TBS is sometimes sensitive to the effects of increased image noise with higher BMI, a corrected version of the TBS (TBS*) was also used to assess bone microarchitecture quality in this cohort. RESULTS: As expected, BMI was positively and negatively related to total BMD (r = 0.22, p < 0.0001) and TBS (r = - 0.12, p < 0.05), respectively. TBS* was found positively and significantly correlated with femoral neck BMD (r = 0.40, p < 0.001), total hip (r = 0.33, p < 0.001) and lumbar spine BMD (r = 0.50, p < 0.001). CONCLUSION: TBS, once removed the effect of BMI, can serve as a good surrogate maker of bone microarchitecture in obese post-menopausal women in addition to BMD.


Assuntos
Densidade Óssea , Osso Esponjoso/fisiologia , Obesidade , Pós-Menopausa , Absorciometria de Fóton , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Vértebras Lombares , Região Lombossacral , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa
11.
Radiol Med ; 125(6): 569-577, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32040719

RESUMO

AIM: To compare clinical success and patient satisfaction of percutaneous cervical nucleoplasty (PCN) and percutaneous cervical discectomy (PCD) in contained cervical disc herniation treatment. MATERIALS AND METHODS: We retrospectively identified 50 consecutive patients in our institution: 24 underwent the PCD treatment and 26 patients were treated by the PCN procedure. All patients complained of radicular pain with or without neck pain; diagnosis of contained cervical disc herniation was obtained by MRI; all patients had received conservative therapy which did not result in symptom improvement. Exclusion from our series consisted of patients who had undergone previous surgery at the indicated level, or those with myelopathy, or those in whom more than a sole herniation was treated in the same session. Overall procedure time, fluoroscopy time, radiation dose and complications were recorded. The MacNab scale score was used to assess clinical success in terms of pain relief at 2- and 6-month follow-up. After 4-6 months, a cervical MRI was obtained in 24 patients. RESULTS: Neither major nor minor complications were reported. Regarding patient satisfaction, overall median modified MacNab score was excellent both at 2 and 6 months after treatment. No significant statistical difference was found in mean modified MacNab score at 2 and 6 months among patients grouped by treatment choice (p = 0.319 and 0.847, respectively); radiation dose was inferior in PCN group than in PCD, with no significant statistical difference. CONCLUSION: PCD and PCN were found to be safe and effective in terms of pain relief in contained cervical herniation treatment.


Assuntos
Vértebras Cervicais , Discotomia Percutânea/métodos , Deslocamento do Disco Intervertebral/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Int J Mol Sci ; 20(24)2019 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-31847375

RESUMO

Despite convincing experimental evidence, epidemiological studies on the effects of serum uric acid (SUA) on bone health are still conflicting since factors influencing SUA bioavailability have not been adequately considered. To shed some light on this issue, we investigated the impact of adiposity and menopause status on the relationship between SUA and bone health. We examined SUA in relation to bone mineral density (BMD) at different skeletal sites and with markers of bone metabolism in 124 pre-menopausal and 234 post-menopausal women and assessed whether adiposity, evaluated by anthropometry and dual x-ray absorptiometry (DXA), might have a discriminant role. After conservative adjustment (covariates: age, hormones treatment, smoking and time since menopause), SUA showed a significant and positive association with total hip BMD (ß = 0.220, p < 0.01) among postmenopausal women, maintained also after adjustment for legs adiposity. Notably, stratification for waist circumference quartiles revealed that the correlation between SUA and total hip BMD was significant (r = 0.444, p = 0.001) in the highest quartile (91-100 cm). Our results suggest that SUA might be beneficial for bone health in postmenopausal women being characterized by a more android fat distribution, ascribing to SUA a discriminant role during menopause transition, potentially relevant also for men.


Assuntos
Tecido Adiposo/metabolismo , Osso e Ossos/metabolismo , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , Distribuição Tecidual/fisiologia , Ácido Úrico/sangue , Absorciometria de Fóton , Adiposidade/fisiologia , Adulto , Disponibilidade Biológica , Índice de Massa Corporal , Densidade Óssea/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Pré-Menopausa/sangue , Estudos Retrospectivos , Ácido Úrico/metabolismo , Circunferência da Cintura/fisiologia
13.
Molecules ; 24(3)2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30759753

RESUMO

Academic journals have published a large number of papers in the therapeutic nuclear medicine (NM) research field in the last 10 years. Despite this, a literature analysis has never before been made to point out the research interest in therapeutic radionuclides (RNs). For this reason, the present study aims specifically to analyze the research output on therapeutic radiometals from 2008 to 2018, with intent to quantify and identify global trends in scientific literature and emphasize the interdisciplinary nature of this research field. The data search targeted conventional (131I, 90Y, 177Lu, 188Re, 186Re, 153Sm, 89Sr, 186Er) and emergent (67Cu, 47Sc, 223Ra, 166Ho, 161Tb, 149Tb, 212Pb/212Bi, 225Ac, 213Bi, 211At, 117mSn) RNs. Starting from this time frame, authors have analyzed and interpreted this scientific trend quantitatively first, and qualitatively after.


Assuntos
Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Humanos , Publicações , Pesquisa
15.
Pol J Radiol ; 84: e522-e529, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32082450

RESUMO

PURPOSE: To evaluate the ability of coronary computed tomography angiography (CCTA) with model-based iterative reconstruction (MBIR) algorithm in detecting significant coronary artery stenosis compared with invasive coronary angiography (ICA). MATERIAL AND METHODS: We retrospectively identified 55 patients who underwent CCTA using the MBIR algorithm with evidence of at least one significant stenosis (≥ 50%) and an ICA within three months. Patients were stratified based on calcium score; stenoses were classified by type and by coronary segment involved. Dose-length-product was compared with the literature data obtained with previous reconstruction algorithms. Coronary artery stenosis was estimated on ICAs based on a qualitative method. RESULTS: CCTA data were confirmed by ICA in 89% of subjects, and in 73% and 94% of patients with CS < 400 and ≥ 400, respectively. ICA confirmed 81% of calcific stenoses, 91% of mixed, and 67% of soft plaques. Both the dose exposure of patients with prospective acquisition (34) and the exposure of the whole population were significantly lower than the standard of reference (p < 0.001 and p = 0.007). CONCLUSIONS: CCTA with MBIR is valuable in detecting significant coronary artery stenosis with a solid reduction of radiation dose. Diagnostic performance was influenced by plaque composition, being lower compared with ICA for patients with lower CAC score and soft plaques; the visualisation of an intraluminal hypodensity could cause false positives, particularly in D1 and MO segments.

16.
Molecules ; 23(8)2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30111708

RESUMO

Scorpionate ligands have played a crucial role in the development of technetium chemistry and, recently, they have also fueled important advancements in the discovery of novel diagnostic imaging agents based on the γ-emitting radionuclide technetium-99m. The purpose of this short review is to provide an illustration of the most general and relevant results in this field, however without being concerned with the details of the analytical features of the various compounds. Thus, emphasis will be given to the description of the general features of technetium complexes with scorpionate ligands including coordination modes, structural properties and an elementary bonding description. Similarly, the most relevant examples of technetium-99m radiopharmaceuticals derived from scorpionate ligands and their potential interest for nuclear imaging will be summarized.


Assuntos
Meios de Contraste/química , Complexos de Coordenação/química , Compostos Radiofarmacêuticos/química , Tecnécio/química , Animais , Barreira Hematoencefálica/metabolismo , Permeabilidade da Membrana Celular , Meios de Contraste/farmacocinética , Complexos de Coordenação/farmacocinética , Humanos , Ligantes , Estrutura Molecular , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Tecidual
17.
Molecules ; 23(3)2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29543722

RESUMO

The influence of effective room temperature on the radiochemical purity of 99mTc-radiopharmaceuticals was reported. This study was born from the observation that in the isolators used for the preparation of the 99mTc-radiopharmaceuticals the temperatures can be higher than those reported in the commercial illustrative leaflets of the kits. This is due, in particular, to the small size of the work area, the presence of instruments for heating, the continuous activation of air filtration, in addition to the fact that the environment of the isolator used for the 99mTc-radiopharmaceuticals preparation and storage is completely isolated and not conditioned. A total of 244 99mTc-radiopharmaceutical preparations (seven different types) have been tested and the radiochemical purity was checked at the end of preparation and until the expiry time. Moreover, we found that the mean temperature into the isolator was significantly higher than 25 °C, the temperature, in general, required for the preparation and storage of 99mTc-radiopharmaceuticals. Results confirmed the radiochemical stability of radiopharmaceutical products. However, as required in the field of quality assurance, the impact that different conditions than those required by the manufacturer on the radiopharmaceuticals quality have to be verified before human administration.


Assuntos
Compostos de Organotecnécio/química , Compostos Radiofarmacêuticos/química , Estabilidade de Medicamentos , Humanos , Compostos de Organotecnécio/normas , Compostos Radiofarmacêuticos/normas , Temperatura
19.
Calcif Tissue Int ; 97(1): 50-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25939647

RESUMO

The main objective of this study was to compare in the assessment of risk of fractures in postmenopausal women two algorithms for 10-year fracture risk evaluation, the WHO-endorsed FRAX(®) and the Italian FRAX-derived version (DeFRA), which considers BMD of different bone sites and allows the inclusion of other data. In a secondary analysis, we compared the performance of the tools in discriminating subjects who sustained previous major fractures from those who did not. The 10-year fracture risk score was evaluated in a sample of 989 climacteric women using FRAX and DeFRA tools. Bone mineral density was also included in the calculation of these algorithms. Comparing how the subjects were assigned to different risk classes by the two tools, we found that DeFRA attributed higher risk categories than FRAX, among women in the subgroups between 50 and 59 and, mostly, 60-69 years of age. ROC curve analysis showed that DeFRA had the same discriminative ability to identify previous major osteoporotic fractures compared to FRAX (AUC = 0.74 for both). If confirmed by prospective studies, our findings would suggest that DeFRA might be ascribed as at least equivalent to FRAX or perhaps slightly most appropriate in the categorization of the fracture risk, particularly in women aged 60-69 years, a period in which bone densitometry analysis is highly recommended.


Assuntos
Densidade Óssea/fisiologia , Fraturas por Osteoporose/epidemiologia , Pós-Menopausa , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Itália/epidemiologia , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Fatores de Risco
20.
BMC Surg ; 13 Suppl 2: S53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24267789

RESUMO

BACKGROUND: Purpose of the study is to define the role of conventional radiology and MRI in the evaluation of pelvic floor hernias in female pelvic floor disorders. METHODS: A MEDLINE and PubMed search was performed for journals before March 2013 with MeSH major terms 'MR Defecography' and 'pelvic floor hernias'. RESULTS: The prevalence of pelvic floor hernias at conventional radiology was higher if compared with that at MRI. Concerning the hernia content, there were significantly more enteroceles and sigmoidoceles on conventional radiology than on MRI, whereas, in relation to the hernia development modalities, the prevalence of elytroceles, edroceles, and Douglas' hernias at conventional radiology was significantly higher than that at MRI. CONCLUSIONS: MRI shows lower sensitivity than conventional radiology in the detection of pelvic floor hernias development. The less-invasive MRI may have a role in a better evaluation of the entire pelvic anatomy and pelvic organ interaction especially in patients with multicompartmental defects, planned for surgery.


Assuntos
Defecografia/métodos , Hérnia/diagnóstico por imagem , Imageamento por Ressonância Magnética , Distúrbios do Assoalho Pélvico/diagnóstico por imagem , Feminino , Humanos
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