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1.
J Vet Sci ; 21(4): e55, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32735093

RESUMO

BACKGROUND: Computed tomography urography (CTU), based on the excretion of contrast medium after its injection, allows visualization of the renal parenchyma and the renal collecting system. OBJECTIVES: To determine the optimal contrast medium dose allocation ratio to apply in split-bolus CTU in dogs. METHODS: This prospective, experimental, exploratory study used 8 beagles. In 3-phase CTU, unenhanced-, nephrographic-, and excretory-phase images were obtained with a single injection of 600 mg iodine/kg iohexol. In split-bolus CTU, two different contrast medium allocation ratios (30% and 70% for split CTU 1; 50% and 50% for split CTU 2) were used. Unenhanced phase image and a synchronous nephrographic-excretory phase image were acquired. RESULTS: Although the attenuation of the renal parenchyma was significantly lower when using both split CTUs than the 3-phase CTU, based on qualitative evaluation, the visualization score of the renal parenchyma of split CTU 1 was as high as that of the 3-phase CTU, whereas the split CTU 2 score was significantly lower than those of the two others. Artifacts were not apparent, regardless of CTU protocol. The diameter and opacification of the ureter in both split CTUs were not significantly different from those using 3-phase CTU. CONCLUSIONS: Split-bolus CTU with a contrast medium allocation ratio of 30% and 70% is feasible for evaluating the urinary system and allows sufficient enhancement of the renal parenchyma and appropriate distention and opacification of the ureter, with similar image quality to 3-phase CTU in healthy dogs. Split-bolus CTU has the advantages of reducing radiation exposure and the number of CT images needed for interpretation.


Assuntos
Meios de Contraste/administração & dosagem , Iohexol/administração & dosagem , Tomografia Computadorizada por Raios X/veterinária , Urografia/veterinária , Animais , Cães , Masculino , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodos
3.
Radiol Med ; 125(12): 1301-1310, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32415474

RESUMO

OBJECTIVES: To evaluate thyroid, arytenoid, and cricoid cartilage invasion on computed tomography (CT) imaging in patients undergoing total laryngectomy for both primary and recurrent laryngeal carcinoma. Secondary endpoint was to compare laryngeal cartilage invasion between primary and recurrent tumours. METHODS: Pre-treatment CT of 40 patients who had undergone total laryngectomy was retrospectively evaluated and compared with histology. Focal erosions of thyroid cartilage were accounted for neoplastic invasion of the inner cortex. Full-thickness thyroid cartilage invasion was defined as a tumour-like tissue replacing thyroid cartilage or extended in extra-laryngeal soft tissues. Sclerosis and erosion of arytenoid and cricoid cartilages were assessed as signs of neoplastic invasion. RESULTS: CT erosion showed perfect agreement for thyroid inner cortex and cricoid cartilage invasion and almost perfect agreement (87%) for arytenoid cartilage invasion. For tumours in contact with thyroid cartilages, the absence of CT erosion underestimated inner cortex infiltration. CT showed perfect agreement in predicting full-thickness thyroid cartilage invasion only in the case of extra-laryngeal neoplastic extension. Arytenoid sclerosis showed poor correlation with neoplastic invasion. For primary tumours, CT demonstrated good (inner cortex 75%; full-thickness 85%), substantial (67.5%), and perfect (100%) accuracy in thyroid, arytenoid, and cricoid cartilage invasion, respectively. No CT differences were observed between primary and recurrent laryngeal tumours. CONCLUSION: Tumour-like tissue extension in the extra-laryngeal soft tissues was accurate in predicting thyroid cartilage full-thickness invasion. Erosions of arytenoid, cricoid, and thyroid cartilages' inner cortex on CT were highly indicative of neoplastic infiltration. No CT difference in cartilage infiltration between primary and recurrent tumours was observed.


Assuntos
Cartilagens Laríngeas/diagnóstico por imagem , Neoplasias Laríngeas/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Recidiva Local de Neoplasia/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Cartilagem Aritenoide/diagnóstico por imagem , Cartilagem Aritenoide/patologia , Meios de Contraste/administração & dosagem , Cartilagem Cricoide/diagnóstico por imagem , Cartilagem Cricoide/patologia , Feminino , Humanos , Iohexol/administração & dosagem , Iohexol/análogos & derivados , Cartilagens Laríngeas/patologia , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Cartilagem Tireóidea/diagnóstico por imagem , Cartilagem Tireóidea/patologia
4.
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
5.
J Comput Assist Tomogr ; 44(2): 230-235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195801

RESUMO

OBJECTIVE: We developed a patient-specific contrast enhancement optimizer (p-COP) that can exploratorily calculate the contrast injection protocol required to obtain optimal enhancement at target organs using a computer simulator. Appropriate contrast media dose calculated by the p-COP may minimize interpatient enhancement variability. Our study sought to investigate the clinical utility of p-COP in hepatic dynamic computed tomography (CT). METHODS: One hundred thirty patients (74 men, 56 women; median age, 65 years) undergoing hepatic dynamic CT were randomly assigned to 1 of 2 contrast media injection protocols using a random number table. Group A (n = 65) was injected with a p-COP-determined iodine dose (developed by Higaki and Awai, Hiroshima University, Japan). In group B (n = 65), a standard protocol was used. The variability of measured CT number (SD) between the 2 groups of aortic and hepatic enhancement was compared using the F test. In the equivalence test, the equivalence margins for aortic and hepatic enhancement were set at 50 and 10 Hounsfield units (HU), respectively. The rate of patients with an acceptable aortic enhancement (250-350 HU) for the diagnosis of hypervascular liver tumors was compared using the χ test. RESULTS: The mean ± SD values of aortic and hepatic enhancement were 311.0 ± 39.9 versus 318.7 ± 56.5 and 59.0 ± 11.5 versus 58.6 ± 11.8 HU in groups A and B, respectively. Although the SD for aortic enhancement was significantly lower in group A (P = 0.006), the SD for hepatic enhancement was not significantly different (P = 0.871). The 95% confidence interval for the difference in aortic and hepatic enhancement between the 2 groups was within the range of the equivalence margins. The number of patients with acceptable aortic enhancement was significantly greater in group A than in group B (P < 0.01). CONCLUSIONS: The p-COP software reduced interpatient variability in aortic enhancement and obtained acceptable aortic enhancement at a significantly higher rate compared with the standard injection protocol for hepatic dynamic CT.


Assuntos
Meios de Contraste/administração & dosagem , Iohexol/administração & dosagem , Neoplasias Hepáticas/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Injeções Intravenosas , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
6.
Int J Pharm Compd ; 24(1): 83-85, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023220

RESUMO

Melphalan is used in selective ophthalmic artery infusion chemotherapy. In the procedure to catheterize the ophthalmic artery in selective ophthalmic artery infusion chemotherapy, the microcatheter is usually filled with an iodinated contrast medium. It is not known whether mixing of iodinated contrast medium with melphalan solutions promotes precipitation of melphalan during selective ophthalmic artery infusion chemotherapy. The objective of the present study was to examine the compatibility of melphalan and iodinated contrast medium. In the experiments, melphalan solutions were prepared with and without iodinated contrast medium (iohexol 300 mg Iodine/mL or ioversol 74%). Melphalan solution of clinically relevant concentration (0.45 mg/mL) in the absence of iodinated contrast medium was evaluated as a reference. The 0.45-mg/mL melphalan solution was diluted with iodinated contrast medium at 1:9 and 1:1 ratios to form solutions comprising iodinated contrast medium at 10% or 50% (v/v), and each was evaluated. The formation of particles was examined using filtration (pore size 0.45 µm) followed by high-performance liquid chromatography at four quarterly time intervals (15 min, 30 min, 45 min, and 60 min) over a 1-hour period after solution preparation. High-performance liquid chromatography analysis of microfiltered solutions did not reveal evidence of melphalan crystal formation over a 60-minute period for the solutions studied. The filtration studies suggest that mixing of the iodinated contrast medium with melphalan solutions does not result in significant melphalan precipitation.


Assuntos
Meios de Contraste/administração & dosagem , Iodo , Iohexol/administração & dosagem , Melfalan , Iodo/química , Artéria Oftálmica
7.
Br J Radiol ; 93(1109): 20190868, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32017607

RESUMO

OBJECTIVE: To assess the impact of piston-based vs peristaltic injection system technology and contrast media viscosity on achievable iodine delivery rates (IDRs) and vascular enhancement in a pre-clinical study. METHODS: Four injectors were tested: MEDRAD® Centargo, MEDRAD® Stellant, CT Exprès®, and CT motion™ using five contrast media [iopromide (300 and 370 mgI ml-1), iodixanol 320 mgI ml-1, iohexol 350 mgI ml-1, iomeprol 400 mgI ml-1]. Three experiments were performed evaluating achievable IDR and corresponding enhancement in a circulation phantom. RESULTS: Experiment I: Centargo provided the highest achievable IDRs with all tested contrast media (p < 0.05). Iopromide 370 yielded the highest IDR with an 18G catheter (3.15 gI/s); iopromide 300 yielded the highest IDR with 20G (2.70 gI/s) and 22G (1.65 gI/s) catheters (p < 0.05).Experiment II: with higher achievable IDRs, piston-based injectors provided significantly higher peak vascular enhancement (up to 48% increase) than the peristaltic injectors with programmed IDRs from 1.8 to 2.4 gI/s (p < 0.05).Experiment III: with programmed IDRs (e.g. 1.5 gI/s) achievable by all injection systems, Centargo, with sharper measured bolus shape, provided significant increases in enhancement of 34-73 HU in the pulmonary artery with iopromide 370 (p < 0.05). CONCLUSION: The tested piston-based injection systems combined with low viscosity contrast media provide higher achievable IDRs and higher peak vascular enhancement than the tested peristaltic-based injectors. With equivalent IDRs, Centargo provides higher peak vascular enhancement due to improved bolus shape. ADVANCES IN KNOWLEDGE: This paper introduces a new parameter to compare expected performance among contrast media: the concentration/viscosity ratio. Additionally, it demonstrates previously unexplored impacts of bolus shape on vascular enhancement.


Assuntos
Meios de Contraste/administração & dosagem , Meios de Contraste/farmacocinética , Desenho de Equipamento , Humanos , Injeções/instrumentação , Iohexol/administração & dosagem , Iohexol/análogos & derivados , Iohexol/farmacocinética , Iopamidol/administração & dosagem , Iopamidol/análogos & derivados , Iopamidol/farmacocinética , Imagens de Fantasmas , Tomografia Computadorizada por Raios X , Ácidos Tri-Iodobenzoicos/administração & dosagem , Ácidos Tri-Iodobenzoicos/farmacocinética , Viscosidade
8.
Thorac Cardiovasc Surg ; 68(3): 253-255, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-30634186

RESUMO

Small pulmonary lesions can be difficult to localize during video-assisted thoracoscopic surgery. Electromagnetic navigation bronchoscopy (ENB) dye marking of the lesion, particularly when guided by cone beam computed tomography in the hybrid operating room (HOR), is an emerging approach. However, issues with confirmation of dye injection and intraoperative visualization of the colored dye can be unpredictable and challenging. To address these uncertainties, we present our technique of ENB dye marking localization of lung nodule using the triple-contrast dye method in the HOR.


Assuntos
Broncoscopia , Corantes/administração & dosagem , Meios de Contraste/administração & dosagem , Fenômenos Eletromagnéticos , Verde de Indocianina/administração & dosagem , Iohexol/administração & dosagem , Neoplasias Pulmonares/diagnóstico por imagem , Azul de Metileno/administração & dosagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Humanos , Injeções Intralesionais , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Valor Preditivo dos Testes , Nódulo Pulmonar Solitário/patologia , Nódulo Pulmonar Solitário/cirurgia , Cirurgia Assistida por Computador , Cirurgia Torácica Vídeoassistida , Carga Tumoral
9.
Acta Radiol ; 61(7): 1001-1007, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31684746

RESUMO

BACKGROUND: Magnetic resonance hysterosalpingography (MR-HSG) is a promising technique in the work-up of female infertility. Few existing MR-HSG studies focus on the comparison between MR-HSG with gold standard examination. PURPOSE: To compare the diagnostic value of MR-HSG with conventional HSG in patients receiving both exams in one day. MATERIAL AND METHODS: This study included 33 infertile women who completed pelvic MR scanning, HSG, and MR-HSG in that order. A traditional HSG contrast agent (iohexol) and a magnetic resonance imaging (MRI) contrast agent (1 mL gadopentetate dimeglumine (Gd-DTPA) blended with 100 mL iohexol) were used to achieve image enhancement. Inter-observer and inter-modality agreements of HSG and MR-HSG exams were assessed. The results were calculated by using the kappa test. Three radiologists who were blinded to the clinical data independently reviewed the MR images. Extratubal abnormalities were analyzed. RESULTS: A total of 62 fallopian tubes of 33 women were included in the study. MR-HSG imaging findings to depict tubal patency were similar to these of HSG (AUC 0.911, sensitivity 0.821, specificity 1.000, positive predictive values 1.000, and negative predictive values 0.872). Pairwise inter-observer agreement among three observers and inter-modality agreement of the diagnosis were excellent (mean kappa 0.863 and 0.835, respectively). In addition, 29 extratubal abnormalities in 21 patients were found on pelvic MR scanning. CONCLUSION: MR-HSG and HSG demonstrated similar results in assessing tubal patency. Because it offers the comprehensive assessment of female pelvic structures, and avoids ionizing radiation, MR-HSG may be used as an alternative imaging technique for evaluation of female infertility.


Assuntos
Meios de Contraste/administração & dosagem , Tubas Uterinas/diagnóstico por imagem , Histerossalpingografia/métodos , Infertilidade Feminina/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Adulto , Feminino , Gadolínio DTPA/administração & dosagem , Humanos , Aumento da Imagem/métodos , Iohexol/administração & dosagem , Estudos Prospectivos , Sensibilidade e Especificidade
11.
Catheter Cardiovasc Interv ; 95(5): 895-903, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31282129

RESUMO

BACKGROUND: Urine flow rate (UFR)-guided and left-ventricular end-diastolic pressure (LVEDP)-guided hydration regimens have been proposed to prevent contrast-induced acute kidney injury (CIAKI). The REnal Insufficiency Following Contrast MEDIA Administration triaL III (REMEDIAL III) is a randomized, multicenter, investigator-sponsored trial aiming to compare these two hydration strategies. METHODS: Patients at high risk for CIAKI (that is, those with estimated glomerular filtration rate ≤ 45 mL/min/1.73 m2 and/or with Mehran's score ≥11 and/or Gurm's score >7) will be enrolled. Patients will be randomly assigned to (a) LVEDP-guided hydration with normal saline (LVEDP-guided group) and (b) UFR-guided hydration carried out by the RenalGuard system (RenalGuard group). Seven-hundred patients (350 in each arm) will be enrolled. In the LVEDP-guided group the fluid infusion rate will be adjusted according to the LVEDP as follows: 5 mL kg-1 hr-1 for LVEDP ≤12 mmHg, 3 mL kg-1 hr-1 for LVEDP 13-18 mmHg, and 1.5 mL kg-1 hr-1 for LVEDP >18 mmHg. In the RenalGuard group hydration with normal saline plus low-dose of furosemide is controlled by the RenalGuard system, in order to reach and maintain a high (>300 mL/hr) UFR. In all cases, iobitridol (a low-osmolar, nonionic contrast agent) will be administered. RESULTS: The primary endpoint is the composite of CIAKI (i.e., serum creatinine increase ≥25% and/or ≥0.5 mg/dL from the baseline to 48 hr after contrast media exposure) and/or acute pulmonary edema. CONCLUSION: The REMEDIAL III will test the hypothesis that the UFR-guided hydration is superior to the LVEDP-guided hydration to prevent the composite of CIAKI and/or acute pulmonary edema.


Assuntos
Lesão Renal Aguda/prevenção & controle , Meios de Contraste/efeitos adversos , Hidratação , Iohexol/análogos & derivados , Rim/efeitos dos fármacos , Solução Salina/administração & dosagem , Urodinâmica , Função Ventricular Esquerda , Remodelação Ventricular , Lesão Renal Aguda/induzido quimicamente , Lesão Renal Aguda/diagnóstico , Lesão Renal Aguda/fisiopatologia , Idoso , Meios de Contraste/administração & dosagem , Feminino , Hidratação/efeitos adversos , Humanos , Iohexol/administração & dosagem , Iohexol/efeitos adversos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Solução Salina/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
12.
Invest Radiol ; 55(1): 38-44, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31524764

RESUMO

OBJECTIVE: The aim of this study was to compare the risk of hypersensitivity reactions to iopromide after intra-arterial (IA) administration and intravenous (IV) administration. MATERIALS AND METHODS: Four observational studies were pooled. Almost half of the study population (48.1%) was from Europe, and one quarter each from China (27.6%) and other Asia countries (24.1%). All patients received iopromide either intra-arterially or intravenously for angiographic procedures (mostly cardio-angiography) or contrast-enhanced computed tomography. A nested case-control analysis, including a multivariable logistic regression model, was performed. Cases were defined by patients with a typical and unequivocal hypersensitivity (assumed non-IgE-mediated) reaction; controls were patients without any recorded reaction. The primary target variable is the odds ratio of having a hypersensitivity reaction after IA versus IV administration. RESULTS: A total of 133,331 patients met the inclusion criteria, 105,460 and 27,871 patients received iopromide IV or IA, respectively. Hypersensitivity reactions were recorded for 822 patients, and 132,509 patients served as controls.Major risk factors for hypersensitivity reactions were method of injection (IV vs IA), age (18 to <50 years vs ≥65 years), history of allergy or previous contrast media reaction (all P < 0.001), and asthma (P = 0.005).A total of 766 patients (0.7%) and 56 patients (0.2%) were recorded with hypersensitivity reactions after IV or IA administration, respectively (P < 0.0001).Adjusted odds ratio (IA vs IV) was 0.23 (95% confidence interval, 0.16-0.32) for all countries together: for China only, 0.22 (0.11-0.44); for all countries without China, 0.36 (0.25-0.53).Most frequent reactions were erythema/urticaria/rash, pruritus, and cough/sneezing. CONCLUSIONS: Hypersensitivity reactions to iopromide were significantly less frequently recorded after IA administrations. This could be related to the delayed and diluted arrival of iopromide to the lungs.


Assuntos
Meios de Contraste/administração & dosagem , Meios de Contraste/efeitos adversos , Hipersensibilidade a Drogas/etiologia , Iohexol/análogos & derivados , Administração Intravenosa , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Injeções Intra-Arteriais , Iohexol/administração & dosagem , Iohexol/efeitos adversos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
13.
Sci Rep ; 9(1): 19699, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31873143

RESUMO

Early diagnosis of kidney diseases in avian species is limited. Endogenous markers currently used in avian practice are not sensitive enough to identify early kidney failure. Consequently, alternative markers should be evaluated. To be able to evaluate these alternative markers, an accurate marker to estimate the GFR should be validated. This study determined the GFR, measured as clearance of exogenous creatinine and exo-iohexol, in six different bird species, i.e. broiler chickens, laying chickens, turkeys, Muscovy ducks, pigeons and African grey parrots (4♀/4♂). To be able to compare the six bird species, normalization to bodyweight (BW) of the GFR was performed, after a good correlation between BW and kidney weight was demonstrated (R² = 0.9836). Clearance of exo-iohexol normalized to BW (mL/min/kg) was determined in all bird species, i.e. 3.09 in broiler chickens; 2.57 in laying chickens; 1.94 in turkeys; 1.29 in pigeons; 2.60 in ducks and 1.11 in parrots. However, these results differed significantly with the clearance of exogenous creatinine: 8.41 in broiler chickens; 9.33 in laying chickens; 5.62 in turkeys; 14.97 in pigeons; 17.59 in ducks and 25.56 in parrots 25.56. Iohexol is preferred to measure the GFR, since it is not prone to tubular reabsorption nor secretion.


Assuntos
Aves/fisiologia , Creatinina/sangue , Taxa de Filtração Glomerular/fisiologia , Testes de Função Renal/veterinária , Animais , Biomarcadores/sangue , Doenças das Aves/sangue , Doenças das Aves/diagnóstico , Doenças das Aves/fisiopatologia , Aves/sangue , Galinhas , Columbidae , Creatinina/administração & dosagem , Creatinina/farmacocinética , Patos , Diagnóstico Precoce , Feminino , Iohexol/administração & dosagem , Iohexol/farmacocinética , Nefropatias/diagnóstico , Nefropatias/fisiopatologia , Nefropatias/veterinária , Testes de Função Renal/métodos , Masculino , Papagaios , Especificidade da Espécie , Perus
14.
J Pharmacol Sci ; 141(1): 49-55, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31611174

RESUMO

BACKGROUND: Contrast-induced nephropathy (CIN) is a frequent cause of hospital-acquired acute kidney injury. Previous animal models developed to explore the pathogenesis of CIN were based primarily on surgery or indomethacin treatment. Thus, we sought to explore a novel CIN rat model comparable to the human CIN. METHODS AND RESULTS: Both serum creatinine and tubular injury score were used to assess the successful establishment of the present model. In our study, dehydration duration and the iohexol dosage were found to be the two most important factors to develop a rat CIN model. And, dehydration for 3 days plus furosemide (10 mL/kg) injection before iohexol (15 mL/kg) administration was demonstrated the optimal strategy. Renal injury induced by 15 mL/kg iohexol was almost twice more severe than 10 mL/kg. Moreover, significant renal function decrease, morphological damage and mitochondrial dysfunction occurred as early as 6 h after iohexol injection, not 24 h as previous studies reported. Unexpectedly, we firstly discovered that dehydration after iohexol administration did not increase the extent of renal damage, indicating that hydration after contrast media exposure may be ineffective. CONCLUSIONS: A novel CIN rat model based on dehydration and iohexol exposure was established and validated to assist in understanding and preventing CIN.


Assuntos
Lesão Renal Aguda , Meios de Contraste/efeitos adversos , Desidratação/complicações , Modelos Animais de Doenças , Iohexol/efeitos adversos , Lesão Renal Aguda/diagnóstico , Lesão Renal Aguda/etiologia , Lesão Renal Aguda/patologia , Lesão Renal Aguda/prevenção & controle , Animais , Biomarcadores/sangue , Meios de Contraste/administração & dosagem , Creatinina/sangue , Furosemida/administração & dosagem , Furosemida/efeitos adversos , Iohexol/administração & dosagem , Túbulos Renais/patologia , Masculino , Ratos Sprague-Dawley
15.
J Comput Assist Tomogr ; 43(5): 718-720, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31609292

RESUMO

Recently, a novel 3-dimensional visualization methodology for volumetric computed tomography data has become available. This method, known as cinematic rendering, uses an advanced lighting model to create photorealistic images from standard computed tomography acquisition data composed of isotropic voxels. We have observed that cinematic rendering visualizations in which patients have been administered dense, positive oral contrast do not have any substantive visual artifacts and can be used to demonstrate bowel pathology to advantage (ie, "virtual fluoroscopy"). In this technical note, we describe our acquisition and visualization parameters, and we also include demonstrative examples.


Assuntos
Meios de Contraste/administração & dosagem , Enterite/diagnóstico por imagem , Imageamento Tridimensional/métodos , Intussuscepção/diagnóstico por imagem , Iohexol/administração & dosagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Artefatos , Feminino , Fluoroscopia , Humanos , Interpretação de Imagem Radiográfica Assistida por Computador
16.
J Comput Assist Tomogr ; 43(5): 736-740, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31609293

RESUMO

OBJECTIVE: The objective of this study was to compare enhancement of the aorta and liver on hepatic dynamic computed tomography scans acquired with contrast material doses based on the lean body weight (LBW) or the total body weight (TBW). METHODS: We randomly divided 529 patients (279 men, 250 women; median age, 66 years) scheduled for hepatic dynamic computed tomography into 2 groups. The LBW patients (n = 278) were injected with 679 mg iodine/kg (men) or 762 mg iodine/kg (women). The TBW group (n = 251) was injected with 600 mg iodine/kg TBW. Each group was subdivided into the 3 classes based on the body mass index (BMI; low, normal, high). Aortic enhancement during the hepatic arterial phase and hepatic enhancement during the portal venous phase was compared. The aortic and hepatic equivalence margins were 100 and 20 Hounsfield units, respectively. RESULTS: Comparison of the median iodine dose in patients with a normal or high BMI showed that it was significantly lower under the LBW protocol than the TBW protocol (558.2 and 507.0 mg iodine/kg, P < 0.001, respectively). However, in patients with a low BMI, the LBW protocol delivered a significantly higher dose than the TBW protocol (620.7 vs 600.0 mg iodine/kg, P < 0.001). The 95% confidence interval for the difference in aortic and hepatic enhancement between the 2 protocols was within the range of the predetermined equivalence margins in all BMI subgroups. CONCLUSIONS: Contrast enhancement was equivalent under both protocols. The LBW protocol can avoid iodine overdosing, especially in patients with a high BMI.


Assuntos
Índice de Massa Corporal , Meios de Contraste/administração & dosagem , Iohexol/administração & dosagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Peso Corporal , Feminino , Humanos , Injeções , Masculino , Estudos Prospectivos
17.
Radiography (Lond) ; 25(4): 346-348, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31582243

RESUMO

INTRODUCTION: Haemodynamic changes may occur with the rapid intravenous injection of contrast media due to the osmolality of such pharmaceuticals. This study sought to evaluate the effect of bolus administration of intravenous contrast media on blood pressure variation during the Contrast-Enhanced Computed Tomography (CECT) of the abdomen. METHODS: The study included 74 patients who underwent abdominal CECT and they were placed in the first group receiving a maximum of 80 ml of iodinated contrast via pressure injector (4 ml/s). A further 74 patients, who underwent non-contrast enhanced abdominal CT, were placed in the second group in which 80 ml of normal saline was administered via the same manner. Patients with hypertension and who were on anti-hypertensive drugs were excluded from the study. Non-invasive blood pressure was monitored before the injection of contrast media/saline and immediately after the portal venous phase for the CECT scan and after 45 s following the administration of normal saline in the non-contrast CT group. Mean systolic and diastolic blood pressures from both groups were compared to find out the effect of contrast bolus administration on blood pressure variation. RESULTS: Both systolic and diastolic blood pressure increased with the injection of contrast media among CECT scan group. No significant changes in systolic and diastolic blood pressure were found before and after the scan in the non-contrast group. CONCLUSION: Bolus administration of 80 ml saline has no effect on blood pressure. The increased blood pressure in contrast enhanced studies was induced by the iodinated contrast media and not by the bolus effect.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Meios de Contraste/administração & dosagem , Abdome/diagnóstico por imagem , Meios de Contraste/efeitos adversos , Estudos Transversais , Humanos , Injeções Intravenosas/efeitos adversos , Injeções Intravenosas/métodos , Iohexol/administração & dosagem , Iohexol/efeitos adversos , Iohexol/análogos & derivados , Estudos Prospectivos , Tomografia Computadorizada por Raios X/efeitos adversos , Tomografia Computadorizada por Raios X/métodos
18.
Eur J Radiol ; 119: 108626, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31430661

RESUMO

PURPOSE: To investigate the image quality, diagnostic accuracy, and dose reduction potential of a split-bolus protocol(SBP) compared with a multiphasic protocol(MPP) in the detection of recurrent or progressive pancreatic ductal adenocarcinoma(PDAC) or cholangiocarcinoma(CC) using contrast- enhanced computed tomography(CECT). MATERIALS AND METHODS: This prospective study included 56 patients who underwent CECT, 28 with our institutional standard MPP(100 ml contrast bolus) and 28 with a novel SBP(110 ml). Radiation exposure was determined in terms of total dose- length product(DLP) and computed tomography dose index(CTDI). Image quality was measured objectively by analysis of attenuation in Hounsfield units(HU) in regions of interest(ROIs) and subjectively by two blinded readers using a Likert scale. Diagnostic accuracy and interreader variability were tested. RESULTS: The total DLP of the SBP group(498.1 ± 43.7 mGy*cm) was significantly lower than in the MPP group(1,092.5 ± 106.9 mGy*cm; p < 0.001). The SBP showed higher contrast enhancement of all critical anatomical structures including portal vein, liver, and pancreas compared with the MPP, except for the aorta(SBP: 326.9 ± 15.7 HU vs. MPP: 246.7 ± 12.2 HU; p < 0.001). Subjective analysis revealed poorer image quality ratings for important landmarks with the MPP (resection surface: p = 0.624, portal vein: p = 0.395, liver p = 0.361). The two blinded readers correlated significantly. Sensitivity, specificity, positive and negative predictive values (PPV/NPV), and overall interreader variabilities correlated significantly. Furthermore, significantly fewer slices per exam were required for the SBP(1,823 vs. 3,235; p < 0.001). CONCLUSION: The SBP provides the same image quality and diagnostic accuracy as an MPP while significantly lowering radiation exposure in CT follow-up of PDAC or CC.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Carcinoma Ductal Pancreático/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Neoplasias Pancreáticas/diagnóstico por imagem , Idoso , Ductos Biliares/diagnóstico por imagem , Ductos Biliares/efeitos da radiação , Protocolos Clínicos , Feminino , Humanos , Iohexol/administração & dosagem , Iohexol/análogos & derivados , Iopamidol/administração & dosagem , Iopamidol/análogos & derivados , Fígado/diagnóstico por imagem , Fígado/efeitos da radiação , Masculino , Tomografia Computadorizada Multidetectores/métodos , Recidiva Local de Neoplasia/diagnóstico por imagem , Pâncreas/diagnóstico por imagem , Pâncreas/efeitos da radiação , Veia Porta/diagnóstico por imagem , Veia Porta/efeitos da radiação , Estudos Prospectivos , Doses de Radiação , Exposição à Radiação , Sensibilidade e Especificidade
19.
Am J Vet Res ; 80(9): 885-890, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31449451

RESUMO

OBJECTIVE: To characterize abdominal lymphatic drainage in cats after thoracic duct ligation (TDL) and cisterna chyli ablation (CCA). ANIMALS: 7 purpose-bred research cats. PROCEDURES: Baseline CT lymphangiography was performed. A popliteal lymph node was injected with iohexol, and images were acquired at 5-minute intervals for 15 minutes. Cats underwent TDL and CCA; methylene blue was used to aid in identifying lymphatic vessels. The CT lymphangiography was repeated immediately after and 30 days after surgery. All cats were euthanized and necropsied. RESULTS: Results of baseline CT lymphangiography were unremarkable for all 7 cats. Only 5 cats completed the study. Leakage of contrast medium at the level of the cisterna chyli was seen on CT lymphangiography images obtained from all cats immediately after surgery. Evaluation of 30-day postoperative CT lymphangiography images revealed small branches entering the caudal vena cava in 2 cats, leakage of contrast medium into the caudal vena cava with no visible branches in 1 cat, and no contrast medium in the caudal vena cava in 2 cats. Contrast medium did not flow beyond the level of the cisterna chyli in any cat. Gross examination during necropsy revealed that all cats had small lymphatic vessels that appeared to connect to local vasculature identified in the region of the cisterna chyli. CONCLUSIONS AND CLINICAL RELEVANCE: Abdominal lymphaticovenous anastomoses formed after TDL and CCA in cats. This would support use of these procedures for treatment of cats with idiopathic chylothorax, although additional studies with clinically affected cats are warranted.


Assuntos
Gatos/cirurgia , Drenagem , Linfografia/veterinária , Ducto Torácico/cirurgia , Abdome , Animais , Quilotórax , Meios de Contraste , Iohexol/administração & dosagem , Ligadura , Linfonodos , Masculino
20.
J Vet Sci ; 20(4): e38, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31364323

RESUMO

Use of a saline chaser has been reported to allow reduction of contrast dose and artifacts during computed tomography (CT) examination in humans. This study assesses the extent of contrast dose by using a saline chaser in abdominal CT scans of normal dogs. Five beagles underwent abdominal CT scans. Three protocols were applied: 600 mg I/kg iohexol without saline chaser (protocol 1), 30% lower dose of iohexol (420 mg I/kg) followed by a 10 mL saline chaser (protocol 2), and 40% lower dose of iohexol (360 mg I/kg) followed by a 10 mL saline chaser (protocol 3). Attenuation values were obtained from aorta, portal vein, and liver parenchyma. The maximum enhancement values (MEVs) in protocol 2 were significantly higher than those in protocols 1 and 3 in the aorta; no difference was seen in the portal vein in all protocols. The liver parenchymal MEVs in protocols 1 and 2 were significantly higher than those obtained in protocol 3. In this study, the use of a saline chaser and a reduced dose of contrast material did not affect vessel enhancement. In conclusion, use of a saline chaser for abdominal CT of dogs is recommended because it allows a 30% reduction of contrast dose without decreasing vascular and hepatic parenchymal enhancement.


Assuntos
Meios de Contraste/análise , Iohexol/análise , Radiografia Abdominal/veterinária , Cloreto de Sódio/administração & dosagem , Tomografia Computadorizada por Raios X/veterinária , Animais , Meios de Contraste/administração & dosagem , Cães , Iohexol/administração & dosagem , Radiografia Abdominal/métodos , Cloreto de Sódio/análise , Tomografia Computadorizada por Raios X/métodos
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