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1.
J Cardiovasc Magn Reson ; 22(1): 66, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32921308

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) is a valuable technique for detecting myocardial disorders and fibrosis. However, we sometimes observe a linear, mid-wall high intensity signal in the basal septum in the short axis view, which often presents diagnostic difficulties in the clinical setting. The purpose of this study was to compare the linear, mid-wall high intensity in the basal septum identified by LGE with the anterior septal perforator arteries identified by coronary computed tomography angiography (CorCTA). METHODS: We retrospectively selected 148 patients who underwent both CorCTA and CMR LGE within 1 year. In the interpretation of LGE, we defined a positive linear high intensity (LHI+) as follows: ① LHI in the basal septum and ② observable for 1.5 cm or more. All other patients were defined as a negative LHI (LHI-). In LHI+ patients, we assessed the correlation between the LHI length and the septal perforator artery length on CorCTA. We also compared the length of the septal perforator artery on CorCTA between LHI+ patients and LHI- patients. RESULTS: A population of 111 patients were used for further analysis. Among these , there were 55 LHI+ patients and 56 LHI- patients. In LHI+ patients, linear regression analysis revealed that there was a good agreement between LGE LHI and septal perforator arteries by CorCTA in terms of length measurements. The measured length of the anterior septal perforator arteries was significantly shorter in LHI- patients than in LHI+ patients (10 ± 8 mm vs. 21 ± 8 mm; P < 0.05). CONCLUSIONS: The LHI observed in the basal septum on short axis LGE may reflect contrast enhancement of the anterior septal perforator arteries. It is important to interpret this septal LHI against knowledge of anatomic structure, to avoid misinterpretations of LGE and prevent misdiagnosis.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Meios de Contraste/administração & dosagem , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Gadolínio DTPA/administração & dosagem , Septos Cardíacos/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Isquemia Miocárdica/diagnóstico por imagem , Idoso , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos
2.
BMJ Case Rep ; 13(9)2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32933911

RESUMO

A 50-year-old woman presented with history of intermittent angina for 2 days and signs of extensive anterior wall myocardial infarction. An urgent coronary angiogram showed a large proximally occluded left anterior descending (LAD) artery with no distal vessel opacification. After one attempt of thrombus aspiration, there was no improvement in Thrombolysis in Myocardial Infarction (TIMI) flow. The aspiration catheter was then parked in the distal vessel beyond the thrombotic lesion and 2 mg of intravenous nicorandil drug mixed with 10 mL of 50% dilute iodinated contrast media was infused slowly. A comparison was made to proximal vessel angiogram and the angioplasty procedure was then completed with a right size stent, restoring TIMI 3 flow in the LAD. This method minimises clot manipulations by avoiding repeated balloon predilatations or thrombus aspiration attempts and thus prevents the occurrence of no-reflow in lesions with large thrombus burden.


Assuntos
Angioplastia , Meios de Contraste/administração & dosagem , Oclusão Coronária/terapia , Nicorandil/administração & dosagem , Trombose/terapia , Vasos Coronários , Combinação de Medicamentos , Feminino , Humanos , Pessoa de Meia-Idade
3.
Medicine (Baltimore) ; 99(36): e21890, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899019

RESUMO

The outcomes of carbon dioxide digital subtraction angiography (CO2-DSA) for performing percutaneous transluminal balloon angioplasty (balloon PTA) in hemodialysis patients has not been fully clarified. The purpose was to compare the outcomes of balloon PTA of hemodialysis shunts in terms of vessel patency between patients treated using CO2-DSA and conventional digital subtraction angiography using iodine contrast medium (C-DSA).We retrospectively evaluated 76 patients (38 males and 38 females, mean age: 65.0 ±â€Š14.0 years). They were under hemodialysis and treated with balloon PTA using CO2-DSA or C-DSA at our institution between 2009 and 2016. Mean duration of the follow-up period was 25.59 ±â€Š21.45 months. We compared the patency rates obtained after CO2-DSA-based balloon PTA with those after C-DSA-based balloon PTA. Secondary patency, which was defined as the duration of patency after all further endovascular interventions until surgical repair, was considered as the endpoint in this study.Overall, 19 and 57 patients underwent CO2-DSA- and C-DSA-based balloon PTA, respectively. CO2-DSA- and C-DSA-based balloon PTA produced clinical success rates of 100% and 96.5%, respectively. Blood vessel injury occurred in one patient who underwent C-DSA-based balloon PTA. No major complications occurred in CO2 group. At 24 months, the post-PTA secondary patency rates of CO2-DSA- and C-DSA-based balloon PTA were 94.1% and 93.9%, respectively (P = .9594).CO2-DSA is safe for hemodialysis patients. Compared with C-DSA, CO2-DSA-based balloon PTA produces have a similar secondary patency rate.


Assuntos
Angiografia Digital/métodos , Angioplastia com Balão/métodos , Dióxido de Carbono/administração & dosagem , Meios de Contraste/administração & dosagem , Diálise Renal/efeitos adversos , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Veia Subclávia/diagnóstico por imagem , Veia Subclávia/patologia , Grau de Desobstrução Vascular
4.
J Cardiovasc Magn Reson ; 22(1): 62, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32878630

RESUMO

BACKGROUND: Intensive endurance exercise may induce a broad spectrum of right ventricular (RV) adaptation/remodelling patterns. Late gadolinium enhancement (LGE) has also been described in cardiovascular magnetic resonance (CMR) of some endurance athletes and its clinical meaning remains controversial. Our aim was to characterize the features of contrast CMR and the observed patterns of the LGE distribution in a cohort of highly trained endurance athletes. METHODS: Ninety-three highly trained endurance athletes (> 12 h training/week at least during the last 5 years; 36 ± 6 years old; 53% male) and 72 age and gender-matched controls underwent a resting contrast CMR. In a subgroup of 28 athletes, T1 mapping was also performed. RESULTS: High endurance training load was associated with larger bi-ventricular and bi-atrial sizes and a slight reduction of biventricular ejection fraction, as compared to controls in both genders (p < 0.05). Focal LGE was significantly more prevalent in athletes than in healthy subjects (37.6% vs 2.8%; p < 0.001), with a typical pattern in the RV insertion points. In T1 mapping, those athletes who had focal LGE had higher extracellular volume (ECV) at the remote myocardium than those without (27 ± 2.2% vs 25.2 ± 2.1%; p < 0.05). CONCLUSIONS: Highly trained endurance athletes showed a ten-fold increase in the prevalence of focal LGE as compared to control subjects, always confined to the hinge points. Additionally, those athletes with focal LGE demonstrated globally higher myocardial ECV values. This matrix remodelling and potential presence of myocardial fibrosis may be another feature of the athlete's heart, of which the clinical and prognostic significance remains to be determined.


Assuntos
Atletas , Cardiomegalia Induzida por Exercícios , Meios de Contraste/administração & dosagem , Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Compostos Organometálicos/administração & dosagem , Resistência Física , Função Ventricular Direita , Remodelação Ventricular , Adaptação Fisiológica , Adulto , Estudos de Casos e Controles , Feminino , Fibrose , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Valor Preditivo dos Testes , Volume Sistólico , Função Ventricular Esquerda , Adulto Jovem
5.
Int J Nanomedicine ; 15: 5333-5344, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801692

RESUMO

Purpose: Cabazitaxel (CBZ) is a new taxane-based antitumor drug approved by the FDA for the treatment of prostate cancer, especially for patients with advanced prostate cancer for whom docetaxel is ineffective or causes aggravation. However, Tween 80 injection can cause serious allergic reactions, and CBZ itself has strong toxicity, adverse reactions, and poor tumor selectivity, which greatly limits its clinical applications. Therefore, the CBZ-loaded bovine serum albumin nanoparticles (CBZ-BSA-Gd-NPs) were developed to overcome the allergenic response of Tween 80 and realize the integration of diagnosis and treatment. Methods: CBZ-BSA-Gd-NPs were prepared by the biomineralization method. The characterization, magnetic resonance imaging (MRI), safety, and antitumor activity of the nanoparticles were evaluated in vitro and in vivo. Results: The prepared nanoparticles were uniform in size (166 nm), with good MRI performance and stability over 24 h. Compared with CBZ-Tween 80 injection, CBZ-BSA-Gd-NPs showed much lower hemolysis, similar tumor inhibition, and enhanced cellular uptake in vitro. The pharmacokinetic behavior of CBZ-BSA-Gd-NPs in rats showed that the retention time of the nanoparticles was prolonged, the clearance rate decreased, and the area under the drug-time curve increased. The distribution of CBZ-BSA-Gd-NPs in nude mice was characterized by UPLC-MS/MS and MRI, and the results showed that CBZ-BSA-Gd-NPs could effectively target tumor tissues with reduced distribution in the heart, liver, spleen, lungs, and kidneys compared with CBZ-Tween 80, which indicated that CBZ-BSA-Gd-NPs not only had a passive targeting effect on tumor tissue but also achieved the integration of diagnosis and treatment. In vivo, CBZ-BSA-Gd-NPs showed improved tumor inhibitory effect with a safer profile. Conclusion: In summary, CBZ-BSA-Gd-NPs can serve as an effective therapeutic drug carrier to deliver CBZ into prostate cancer, and realize the integration of diagnosis and therapy.


Assuntos
Antineoplásicos/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias da Próstata/tratamento farmacológico , Soroalbumina Bovina/administração & dosagem , Taxoides/administração & dosagem , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Cromatografia Líquida , Meios de Contraste/administração & dosagem , Meios de Contraste/farmacocinética , Docetaxel , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Humanos , Imagem por Ressonância Magnética , Masculino , Camundongos Endogâmicos BALB C , Nanopartículas/química , Neoplasias da Próstata/diagnóstico por imagem , Ratos Sprague-Dawley , Soroalbumina Bovina/farmacocinética , Espectrometria de Massas em Tandem , Taxoides/farmacocinética , Distribuição Tecidual
6.
J Cardiovasc Magn Reson ; 22(1): 53, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32684167

RESUMO

BACKGROUND: Conventional 2D inversion recovery (IR) and phase sensitive inversion recovery (PSIR) late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) have been widely incorporated into routine CMR for the assessment of myocardial viability. However, reliable suppression of fat signal, and increased isotropic spatial resolution and volumetric coverage within a clinically feasible scan time remain a challenge. In order to address these challenges, this work proposes a highly efficient respiratory motion-corrected 3D whole-heart water/fat LGE imaging framework. METHODS: An accelerated IR-prepared 3D dual-echo acquisition and motion-corrected reconstruction framework for whole-heart water/fat LGE imaging was developed. The acquisition sequence includes 2D image navigators (iNAV), which are used to track the respiratory motion of the heart and enable 100% scan efficiency. Non-rigid motion information estimated from the 2D iNAVs and from the data itself is integrated into a high-dimensional patch-based undersampled reconstruction technique (HD-PROST), to produce high-resolution water/fat 3D LGE images. A cohort of 20 patients with known or suspected cardiovascular disease was scanned with the proposed 3D water/fat LGE approach. 3D water LGE images were compared to conventional breath-held 2D LGE images (2-chamber, 4-chamber and stack of short-axis views) in terms of image quality (1: full diagnostic to 4: non-diagnostic) and presence of LGE findings. RESULTS: Image quality was considered diagnostic in 18/20 datasets for both 2D and 3D LGE magnitude images, with comparable image quality scores (2D: 2.05 ± 0.72, 3D: 1.88 ± 0.90, p-value = 0.62) and overall agreement in LGE findings. Acquisition time for isotropic high-resolution (1.3mm3) water/fat LGE images was 8.0 ± 1.4 min (3-fold acceleration, 60-88 slices covering the whole heart), while 2D LGE images were acquired in 5.6 ± 2.2 min (12-18 slices, including pauses between breath-holds) albeit with a lower spatial resolution (1.40-1.75 mm in-plane × 8 mm slice thickness). CONCLUSION: A novel framework for motion-corrected whole-heart 3D water/fat LGE imaging has been introduced. The method was validated in patients with known or suspected cardiovascular disease, showing good agreement with conventional breath-held 2D LGE imaging, but offering higher spatial resolution, improved volumetric coverage and good image quality from a free-breathing acquisition with 100% scan efficiency and predictable scan time.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Adiposidade , Água Corporal/química , Doenças Cardiovasculares/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Coração/diagnóstico por imagem , Imageamento Tridimensional , Imagem por Ressonância Magnética , Compostos Organometálicos/administração & dosagem , Tecido Adiposo/fisiopatologia , Adulto , Idoso , Suspensão da Respiração , Técnicas de Imagem de Sincronização Cardíaca , Doenças Cardiovasculares/fisiopatologia , Eletrocardiografia , Feminino , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
7.
Br J Radiol ; 93(1113): 20200340, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32644824

RESUMO

OBJECTIVES: To investigate if low-keV virtual monoenergetic images (VMI40keV) from abdominal spectral detector CT (SDCT) with reduced intravenous contrast media application (RCM) provide abdominal assessment similar to conventional images with standard contrast media (SCM) dose. METHODS: 78 patients with abdominal SDCT were retrospectively included: 41 patients at risk for adverse reactions who received 44 RCM examinations with 50 ml and 37 patients who underwent 44 SCM examinations with 100 ml of contrast media (CM) and who were matched for effective body diameters. RCM, SCM images and RCM-VMI40keV were reconstructed. Attenuation and signal-to-noise ratio (SNR) of liver, pancreas, kidneys, lymph nodes, psoas muscle, aorta and portal vein were assessed ROIs-based. Contrast-to-noise ratios (CNR) of lymph nodes vs aorta/portal vein were calculated. Two readers evaluated organ/vessel contrast, lymph node delineation, image noise and overall assessability using 4-point Likert scales. RESULTS: RCM were inferior to SCM images in all quantitative/qualitative criteria. RCM-VMI40keV and SCM images showed similar lymph node and muscle attenuation (p = 0.83,0.17), while for all other ROIs, RCM-VMI40keV showed higher attenuation (p ≤ 0.05). SNR was comparable between RCM-VMI40keV and SCM images (p range: 0.23-0.99). CNR of lymph nodes was highest in RCM-VMI40keV (p ≤ 0.05). RCM-VMI40keV received equivalent or higher scores than SCM in all criteria except for organ contrast, overall assessability and image noise, where SCM were superior (p ≤ 0.05). However, RCM-VMI40keV received proper or excellent scores in 88.6/94.2/95.4% of the referring cases. CONCLUSIONS: VMI40keV counteract contrast deterioration in CM reduced abdominal SDCT, facilitating diagnostic assessment. ADVANCES IN KNOWLEDGE: SDCT-derived VMI40keV provide adequate depiction of vessels, organs and lymph nodes even at notable CM reduction.


Assuntos
Abdome/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Tomografia Computadorizada por Raios X , Aorta/diagnóstico por imagem , Meios de Contraste/efeitos adversos , Feminino , Humanos , Injeções Intravenosas , Compostos de Iodo/administração & dosagem , Rim/diagnóstico por imagem , Fígado/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Veia Porta/diagnóstico por imagem , Músculos Psoas/diagnóstico por imagem , Estudos Retrospectivos , Razão Sinal-Ruído
8.
PLoS One ; 15(6): e0234311, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32511272

RESUMO

OBJECTIVE: To compare the performance of an 18-gauge nonfenestrated catheter (18-NFC) with a 22-gauge fenestrated catheter (22-FC) for cardiac CT angiography (CCTA) in patients with suspected coronary heart disease. SUBJECTS AND METHODS: 74 consecutive patients imaged on a 2nd generation dual-source CT with arterial phase CCTA were included in this retrospective investigation to either an 18-NFC or 22-FC. In comparison to the 18-NFC, the 22-FC has three additional perforations for contrast agent dispersal proximal to the tip. We examined the two groups for differences in their average attenuation in the right and left ventricles (RV, LV) and in the atrium (RA, LA) as well as in the proximal right coronary artery (RCA) and the left main coronary artery (LM). The averages were calculated for both the 18-NFC and 22-FC. RESULTS: Catheters were successfully placed on the first attempt 97% (36/37) for 18-NFC and 95% (35/37) for the 22-FC. The following enhancement levels were measured: 22-FC (in Hounsfield-Units (HU)): RV = 203±29, LV = 523±36, RA = 198±29, LA = 519±38, RCA = 547±26, LM = 562±25; 18-NFC: RV = 146±26, LV = 464±32, RA = 141±24, LA = 438±35, RCA = 501±23, LM = 523±23; RV (p = 0,03), LV (p = 0.12), RA (p = 0.02), LA (p = 0.04), RCA (p = 0.3), LM (p = 0.33). CONCLUSION: No significant differences in attenuation levels as well as in image quality of the coronary arteries were found between NFC and FC. Nevertheless, the 22-gauge FC examinations showed significantly higher attenuation in the left and right atrium as well as the right ventricle. Patients with poor venous access may benefit from a smaller gauge catheter that can deliver sufficiently high flow rates for CCTA.


Assuntos
Angiografia por Tomografia Computadorizada/instrumentação , Angiografia Coronária/instrumentação , Doença das Coronárias/diagnóstico por imagem , Dispositivos de Acesso Vascular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste/administração & dosagem , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
9.
Lancet ; 395(10242): 2008-2020, 2020 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-32593337

RESUMO

Pancreatic cancer is a highly fatal disease with a 5-year survival rate of approximately 10% in the USA, and it is becoming an increasingly common cause of cancer mortality. Risk factors for developing pancreatic cancer include family history, obesity, type 2 diabetes, and tobacco use. Patients typically present with advanced disease due to lack of or vague symptoms when the cancer is still localised. High quality computed tomography with intravenous contrast using a dual phase pancreatic protocol is typically the best method to detect a pancreatic tumour and to determine surgical resectability. Endoscopic ultrasound is an increasingly used complementary staging modality which also allows for diagnostic confirmation when combined with fine needle aspiration. Patients with pancreatic cancer are often divided into one of four categories based on extent of disease: resectable, borderline resectable, locally advanced, and metastatic; patient condition is also an important consideration. Surgical resection represents the only chance for cure, and advancements in adjuvant chemotherapy have improved long-term outcomes in these patients. Systemic chemotherapy combinations including FOLFIRINOX (5-fluorouracil, folinic acid [leucovorin], irinotecan, and oxaliplatin) and gemcitabine plus nab-paclitaxel remain the mainstay of treatment for patients with advanced disease. Data on the benefit of PARP inhibition as maintenance therapy in patients with germline BRCA1 or BRACA2 mutations might prove to be a harbinger of advancement in targeted therapy. Additional research efforts are focusing on modulating the pancreatic tumour microenvironment to enhance the efficacy of the immunotherapeutic strategies.


Assuntos
Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/terapia , Administração Intravenosa , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteína BRCA1/efeitos dos fármacos , Proteína BRCA1/genética , Proteína BRCA2/efeitos dos fármacos , Proteína BRCA2/genética , Quimioterapia Adjuvante/métodos , Meios de Contraste/administração & dosagem , Dano ao DNA/efeitos dos fármacos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Humanos , Imunoterapia/métodos , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Fatores de Risco , Taxa de Sobrevida , Tomografia Computadorizada por Raios X/métodos , Microambiente Tumoral/efeitos dos fármacos
10.
Int J Cardiovasc Imaging ; 36(10): 2051-2059, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32506286

RESUMO

To compare intravenous contrast material (CM) injection protocols for dual-energy CT pulmonary angiography (CTPA) in patients with suspected acute pulmonary embolism with regard to image quality and pulmonary perfused blood volume (PBV) values. A total of 198 studies performed with four CM injection protocols varying in CM volume and iodine delivery rates (IDR) were retrospectively included: (A) 60 ml at 5 ml/s (IDR = 1.75gI/s), (B) 50 ml at 5 ml/s (IDR = 1.75gI/s), (C) 50 ml at 4 ml/s (IDR = 1.40gI/s), (D) 40 ml at 3 ml/s (IDR = 1.05gI/s). Image quality and PBV values at different resolution settings were compared. Pulmonary arterial tract attenuation was highest for protocol A (397 ± 110 HU; p vs. B = 0.13; vs. C = 0.02; vs. D < 0.001). CTPA image quality of protocol A was rated superior compared to protocols B and D by reader 1 (p = 0.01; < 0.001), and superior to protocols B, C and D by reader 2 (p < 0.001; 0.02; < 0.001). Otherwise, there were no significant differences in CTPA quality ratings. Subjective iodine map ratings did not vary significantly between protocols A, B, and C. Both readers rated protocol D inferior to all other protocols (p < 0.05). PBV values did not vary significantly between protocols A and B at resolution settings of 1, 4 and 10 (p = 0.10; 0.10; 0.09), while otherwise PBV values displayed a decreasing trend from protocol A to D (p < 0.05). Higher CM volume and IDR are associated with superior CTPA and iodine map quality and higher absolute PBV values.


Assuntos
Angiografia por Tomografia Computadorizada , Meios de Contraste/administração & dosagem , Iopamidol/análogos & derivados , Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Administração Intravenosa , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Iopamidol/administração & dosagem , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Artéria Pulmonar/fisiopatologia , Embolia Pulmonar/fisiopatologia , Reprodutibilidade dos Testes , Estudos Retrospectivos
12.
Int J Nanomedicine ; 15: 3057-3070, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431501

RESUMO

Background: Position of gadolinium atom(s) plays a key role in contrast enhancement of gadolinium-based contrast agents. To gain a better understanding of effects of distance of gadolinium in relation to the nanoconjugate platform, we designed and synthesized single- and multi-arm ("star") gadolinium conjugates equipped with antibody and peptides for targeting. The contrast agents were studied for their tumor imaging performance in a glioma mouse model. Materials and Methods: Antibody- and peptide-targeted nano contrast agents (NCAs) were synthesized using polymalic acid platforms of different sizes. Gadolinium-DOTA and intermediates were attached as amides and targeting agents such as antibodies and peptides as thioethers. For in vivo experiments, we used human U87MG xenografts as glioma models. Magnetic resonance imaging (MRI) was performed on a Bruker BioSpec 94/20USR 9.4 T small-animal scanner. Delivery of contrast agents across the blood-brain barrier was studied by fluorescent microscopy. Results: All contrast agents accumulated into tumor and showed composition-dependent imaging performance. Peptide-targeted mini-NCAs had hydrodynamic diameters in the range 5.2-9.4 nm and antibody-targeted NCAs had diameters in the range 15.8-20.5 nm. Zeta potentials were in the range of -5.4--8.2 mV and -4.6--8.8 mV, respectively. NCAs showed superior relaxivities compared to MultiHance at 9.4 T. The signal enhancement indicated maximum accumulation in tumor 30-60 minutes after intravenous injection of the mouse tail vein. Only targeted NCAs were retained in tumor for up to 3 hours and displayed contrast enhancement. Conclusion: The novel targeted NCAs with star-PEG features displayed improved relaxivity and greater contrast compared with commercial MultiHance contrast agent. The enhancement by mini-NCAs showed clearance of tumor contrast after 3 hours providing a suitable time window for tumor diagnosis in clinics. The technology provides a great tool with the promise of differential MRI diagnosis of brain tumors.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Glioblastoma/diagnóstico por imagem , Compostos Heterocíclicos/administração & dosagem , Imagem por Ressonância Magnética/métodos , Compostos Organometálicos/administração & dosagem , Animais , Linhagem Celular Tumoral , Meios de Contraste/química , Meios de Contraste/farmacocinética , Modelos Animais de Doenças , Feminino , Humanos , Meglumina/administração & dosagem , Meglumina/análogos & derivados , Meglumina/farmacocinética , Camundongos Nus , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Compostos Organometálicos/farmacocinética , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Br J Radiol ; 93(1111): 20190995, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32436788

RESUMO

OBJECTIVES: To perform CT pulmonary angiography (CTPA) using a minimal amount of iodinated contrast media. METHODS: 47 patients (25 females) with mean age 69 years (range 41-82 years) referred for contrast-enhanced chest CT were prospectively included in this Phase IV clinical drug trial. All participants underwent a study specific CTPA in addition to the chest CT. The participants received 80 mg I/kg body weight Iohexol contrast media using a preparatory saline bolus, a dual flow contrast/saline bolus and a saline flush, and a scanner protocol with 80 kVp dual source high-pitch mode. Three readers independently assessed the image quality on the 3-point scale non-diagnostic, adequate or good-excellent image quality. Additionally, the pulmonary arterial contrast opacification was measured. RESULTS: On average, the patients received 16.8 ml Iohexol 350 mg I/mL (range 12-20 ml). Mean patient weight was 71 kg (range 50-85 kg). Identically for all readers, pulmonary embolism (PE) was detected in 1/47 participants. The median number of examinations visually scored concerning pulmonary embolism as good-excellent was 47/47 (range 44-47); adequate 0/47 (0-3) and non-diagnostic 0/47 (range 0-0). The proportion adequate or better examinations was for all readers 47/47, 100% [95% confidence interval 92-100%]. The mean attenuation ± standard deviation in the pulmonary trunk was 325 ± 72 Hounsfield unit (range 165-531 Hounsfield unit). CONCLUSIONS: Diagnostic CTPA with 17 ml contrast media is possible in non-obese patients using low kVp, high pitch and carefully designed contrast media administration. ADVANCES IN KNOWLEDGE: By combining several procedures in a CTPA protocol, the contrast media dose can be minimized.


Assuntos
Meios de Contraste/administração & dosagem , Iohexol/administração & dosagem , Embolia Pulmonar/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos Clínicos , Angiografia por Tomografia Computadorizada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem
14.
J Stroke Cerebrovasc Dis ; 29(7): 104828, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32404284

RESUMO

BACKGROUND: Pathomechanism of secondary degeneration in remote regions after ischemic stroke has not been totally clarified. Contrast-enhanced MRI with injecting Gd-DTPA in cisterna magna (CM) is regarded as an efficient method to measure glymphatic system function in brain. Our research aimed at evaluating glymphatic system changes in secondary degeneration areas by contrast-enhanced MRI. METHODS: Ischemic stroke was induced by left middle cerebral artery occlusion (MCAO) model. A total of 12 Sprague-Dawley rats were randomly divided into three groups: control group with sham operations (n=4), the group of acute phase (1 day after MCAO) (n=4), and the group of subacute phase (7 days after MCAO) (n=4). Contrast-enhanced MRI was performed in 1days or 7days after operations respectively. All rats received an intrathecal injection of Gd-DTPA (2µl/min, totally 20µl) and high-resolution 3D T1-weighted MRI for 6 h. The time course of the signal-to-noise ratio (SNR) in substantia Nigra (SN) and ventral thalamic nucleus (VTN) was evaluated between two hemispheres in all rats. RESULTS: In control group without ischemia, time-to-peak of SNR in SN was earlier than that in VTN. There were no differences of SNR between two hemispheres after intrathecal Gd-DTPA administration. In the group of acute phase, MRI revealed similar time course and time-to-peak of SNR between ipsilateral and contralateral VTN, while a tendency of higher SNR in ipsilateral SN than contralateral SN at 4h, 5h, 6h after Gd-DTPA injection. And time-to-peak of SNR was similar in bilateral SN. In the group of subacute phase, time-to-peak of SNR was similar in bilateral VTN, while longer in ipsilateral SN compared with contralateral side. In addition, SNR in T1WI in ipsilateral was significantly higher than SNR in contralateral SN and VTN at 5h (VTN, P= 0.003; SN, P=0.004) and 6h (VTN, P=0.015; SN, P=0.006) after Gd-DTPA injection. CONCLUSION: Glymphatic system was impaired in ipsilateral SN and VTN after ischemic stroke, which may contribute to neural degeneration.


Assuntos
Meios de Contraste/administração & dosagem , Gadolínio DTPA/administração & dosagem , Sistema Glinfático/diagnóstico por imagem , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Imagem por Ressonância Magnética , Degeneração Neural , Substância Negra/diagnóstico por imagem , Núcleos Ventrais do Tálamo/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Sistema Glinfático/patologia , Sistema Glinfático/fisiopatologia , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Valor Preditivo dos Testes , Ratos Sprague-Dawley , Razão Sinal-Ruído , Substância Negra/patologia , Substância Negra/fisiopatologia , Fatores de Tempo , Núcleos Ventrais do Tálamo/patologia , Núcleos Ventrais do Tálamo/fisiopatologia
15.
Int J Cardiovasc Imaging ; 36(9): 1791-1799, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32419092

RESUMO

The aim of this study was to investigate the image quality and radiation dose of different scanning protocols in dual-source CT cardiothoracic angiography for children with tetralogy of Fallot (TOF). Seventy-five consecutive children with known or suspected TOF were enrolled to undergo prospective ECG-triggering sequential dual-source CT (DSCT) cardiothoracic angiography. According to the scanning protocols, these patients were randomly divided into 3 groups: fixed delay time (FDT, n = 25, group A), automatic bolus-tracking (ABT, n = 25, group B) and manual bolus-tracking (MBT, n = 25, group C). Subjective and objective image quality were evaluated. The radiation doses were recorded. The image quality scores of group C were significantly higher than those of group A and B. The absolute value of difference (D-value) on CT attenuation between left (CTLV) and right ventricle (CTRV) in group C was significantly lower than that in group A and B. The total effective dose of groups A, B and C were 0.39 ± 0.06 mSv, 0.40 ± 0.07 mSv and 0.40 ± 0.08 mSv, respectively. There was no significant difference among 3 groups (P = 0.722). Scanning protocol has significantly impacts on the image quality of cardiovascular structures for TOF patients. Compared with the conventional scanning protocols FDT and ABT, the MBT technique provides high image quality and achieves more homogenous attenuation among different patients with TOF.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Doses de Radiação , Exposição à Radiação/prevenção & controle , Tetralogia de Fallot/diagnóstico por imagem , Técnicas de Imagem de Sincronização Cardíaca , Angiografia por Tomografia Computadorizada/efeitos adversos , Meios de Contraste/administração & dosagem , Angiografia Coronária/efeitos adversos , Vasos Coronários/fisiopatologia , Eletrocardiografia , Feminino , Humanos , Lactente , Masculino , Tomografia Computadorizada Multidetectores/efeitos adversos , Variações Dependentes do Observador , Valor Preditivo dos Testes , Exposição à Radiação/efeitos adversos , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Tetralogia de Fallot/fisiopatologia
16.
Curr Cardiol Rep ; 22(7): 47, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32472218

RESUMO

PURPOSE OF REVIEW: This review was undertaken to summarise recent data relating to T1 and T2 relaxation times in the assessment of myocarditis using cardiac MRI, and the effect new studies have had on the established diagnostic criteria, leading to recently proposed revised criteria for the cardiac MRI assessment of myocarditis. RECENT FINDINGS: In 2018, updates to the 2009 Lake Louise Criteria (LLC) were proposed, based on studies showing improved accuracy of T1 mapping techniques over T1 signal intensity ratio-based imaging, although for the detection of myocardial oedema either T2-weighted images or increased T2 relaxation times can be used. Non-ischaemic distribution of scar on late gadolinium-enhanced (LGE) T1-weighted imaging remains in the newly revised criteria, which, although can have low sensitivity due to fibrosis presenting diffusely or due to CMR being performed early in the disease process before scar formation, remains in the LLC due to its high specificity. Early gadolinium enhancement has been removed from the LLC, as T1 quantification has higher diagnostic accuracy for the detection of myocardial injury. In the CMR assessment of myocarditis, T1 and T2 quantifications are now recommended over T1- and T2-weighted imaging. Late gadolinium enhancement in a non-ischaemic pattern remains in the updated criteria, whereas early gadolinium enhancement has been superseded by T1 quantification.


Assuntos
Meios de Contraste/administração & dosagem , Gadolínio/administração & dosagem , Imagem por Ressonância Magnética/métodos , Miocardite/diagnóstico por imagem , Doença Aguda , Edema Cardíaco/diagnóstico , Humanos , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Miocárdio , Valor Preditivo dos Testes , Troponina/sangue
18.
Br J Radiol ; 93(1110): 20200020, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32228302

RESUMO

OBJECTIVE: We report a novel method to provide excellent anatomical depiction of a dural arteriovenous fistula (dAVF) for surgical planning. METHODS: A 78-year-old female presented with progressive back pain, deteriorating mobility and urinary incontinence with a background of obesity and severe osteoarthritis. Initial MRI suspected dAVF and subsequent spinal angiography encountered an extremely tortuous and arteriosclerotic aorta, hence catheterisation of the segmental-intercostal and lumbar vessels proved challenging. Contrast injection into the aortic arch via a pigtail catheter for arterial-phase CT angiogram of the descending aorta was performed. RESULTS: This modality of imaging delineated the dAVF showing extensive involvement of the whole spine accounting for the patient's symptoms. Furthermore this allowed characterisation of bony anatomy in relation to the fistula facilitating precise surgical approach. The dAVF was successfully disconnected through a localised laminectomy centred over the lesion. CONCLUSION: This specific technique for dAVF characterisation has not been previously reported, although trans-venous angiography has been used to some effect. In view of diagnostic and therapeutic technical difficulties that are often faced in such patients, this technique may be a useful alternative that is not only helpful in accurate diagnosis but helps in providing an invaluable guide for the surgical approach. ADVANCES IN KNOWLEDGE: This case highlights the difficulties that one may be faced within cases of tortuous vasculature and the obese patient population. With this in mind we demonstrate how a unique hybridised technique may provide valuable alternative to the neurosciences team should such a future scenario arise.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/cirurgia , Angiografia por Tomografia Computadorizada/métodos , Idoso , Angiografia/métodos , Angiografia Digital , Aorta Torácica/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/complicações , Meios de Contraste/administração & dosagem , Feminino , Humanos , Imagem por Ressonância Magnética , Obesidade/complicações
19.
Cancer Radiother ; 24(5): 453-462, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278653

RESUMO

Neuroimaging and especially MRI has emerged as a necessary imaging modality to detect, measure, characterize and monitor brain tumours. Advanced MRI sequences such as perfusion MRI, diffusion MRI and spectroscopy as well as new post-processing techniques such as automatic segmentation of tumours and radiomics play a crucial role in characterization and follow up of brain tumours. The purpose of this review is to provide an overview on anatomical and functional MRI use for brain tumours boundaries determination and tumour characterization in the specific context of radiotherapy. The usefulness of anatomical and functional MRI on particular challenges posed by radiotherapy such as pseudo progression and pseudo esponse and new treatment strategies such as dose painting is also described.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Neuroimagem/métodos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Meios de Contraste/administração & dosagem , Progressão da Doença , Glioblastoma/diagnóstico por imagem , Glioblastoma/radioterapia , Glioma/diagnóstico por imagem , Glioma/radioterapia , Humanos , Espectroscopia de Ressonância Magnética/métodos , Gradação de Tumores , Técnica de Subtração , Resultado do Tratamento
20.
Br J Radiol ; 93(1110): 20200063, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32271626

RESUMO

Multiparametric ultrasound (MPUS), combining conventional techniques (greyscale and colour Doppler ultrasound), ultrasound strain elastography, and contrast-enhanced ultrasound (CEUS), has been successfully used in the assessment of adult scrotal pathology. Contrast-enhanced ultrasound can confidently establish testicular tissue vascularity even in the small-volume paediatric testis. Elastography provides further assessment of tissue stiffness, potentially adding useful diagnostic information. In children, ultrasonography is particularly advantageous, being safe, radiation-free and negating the need for sedation or general anaesthesia during the imaging evaluation. In this review article, we aim to familiarise readers with the MPUS scanning protocol used for paediatric scrotal examination and provide an overview of scrotal MPUS features, with particular focus to clinical indications where MPUS may be advantageous over conventional ultrasonography.


Assuntos
Doenças dos Genitais Masculinos/diagnóstico por imagem , Escroto/diagnóstico por imagem , Ultrassonografia/métodos , Abscesso/diagnóstico por imagem , Adolescente , Fatores Etários , Criança , Contraindicações de Medicamentos , Meios de Contraste/administração & dosagem , Meios de Contraste/efeitos adversos , Cistos/diagnóstico por imagem , Ecocardiografia Doppler em Cores , Técnicas de Imagem por Elasticidade/métodos , Epididimite/diagnóstico por imagem , Humanos , Recém-Nascido , Infarto/diagnóstico por imagem , Lipoma/diagnóstico por imagem , Masculino , Fosfolipídeos/administração & dosagem , Fosfolipídeos/efeitos adversos , Escroto/lesões , Torção do Cordão Espermático/diagnóstico por imagem , Hexafluoreto de Enxofre/administração & dosagem , Hexafluoreto de Enxofre/efeitos adversos , Neoplasias Testiculares/diagnóstico por imagem , Testículo/irrigação sanguínea , Testículo/diagnóstico por imagem , Testículo/lesões
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