Contrast medium induced nephropathy is the third most common cause of renal failure for inpatients and represents the 10% of all acute kidney injury occurring during hospital-stay. It is associated with prolonged hosp...Contrast medium induced nephropathy is the third most common cause of renal failure for inpatients and represents the 10% of all acute kidney injury occurring during hospital-stay. It is associated with prolonged hospitalization, cost increase and, above all, an unfavourable short- and long-term prognosis. Here, the authors discuss about the contrast medium induced nephropathy prevention strategies, from the identification of patients at risk and drugs potentially nephrotoxic, to the hydration with possible administration of drugs that appeared to be, in some contexts, nephron-protective, and finally we analyze the radiological procedure aimed at the correct choice of type and administration modality of the contrast medium according to current literature.展开更多
Radiocontrast-induced nephropathy(RCIN) is an acute and severe complication after coronary angiography,particularly for patients with pre-existing chronic kidney disease(CKD).It has been associated with both short-and...Radiocontrast-induced nephropathy(RCIN) is an acute and severe complication after coronary angiography,particularly for patients with pre-existing chronic kidney disease(CKD).It has been associated with both short-and long-term adverse outcomes,including the need for renal replacement therapy,increased length of hospital stay,major cardiac adverse events,and mortality.RCIN is generally defined as an increase in serum creatinine concentration of 0.5 mg/dL or 25%above baseline within 48 h after contrast administration.There is no effective therapy once injury has occurred,therefore,prevention is the cornerstone for all patients at risk for acute kidney injury(AKI).There is a small but growing body of evidence that prevention of AKI is associated with a reduction in later adverse outcomes.The optimal strategy for preventing RCIN has not yet been established.This review discusses the principal risk factors for RCIN,evaluates and summarizes the evidence for RCIN prophylaxis,and proposes recommendations for preventing RCIN in CKD patients undergoing coronary angiography.展开更多
Objective: Contrast induced nephropathy (CIN) is the third leading cause of hospital acquired renal failure. The mechanism of CIN is not fully understood. The objectives of this study were to investigate the expressio...Objective: Contrast induced nephropathy (CIN) is the third leading cause of hospital acquired renal failure. The mechanism of CIN is not fully understood. The objectives of this study were to investigate the expression changes of the four subtypes of adenosine receptors (A1AR, A2AAR, A2BAR, and A3AR) following administration of contrast media in mice. Methods: C57BL/6J mice were randomized into treatment and control groups. Iodixanol (IDX) was administered to two treatment groups through retroorbital injection at two different dosages, 0.75 gI/kg and 2.75 gI/kg. Phosphate buffered saline (PBS) was given to the control group. Mice kidneys were harvested at day 3 and day 7 after Iodixanol administration. Kidney injuries and function were evaluated according to Hematoxylin and eosin stain, Ki67 protein expression, and TUNEL assay of paraffin embedded kidney sections, and plasma creatinine assay. RNA and protein were extracted from the kidney specimens. A1AR, A2AAR, A2BAR, and A3AR RNA and protein level of the samples were assessed using qRT-PCR and Western blotting, with GAPDH as an endogenous control. Results: H&E staining showed no significant histopathology injuries after Iodixanol administration. No evidence of kidney injury and functional impairment was found. However, there was an increased number of A1AR, A2AAR, A2BAR, and A3AR RNA transcripts detected in the kidney 3 days after Iodixanol injection. The RNA levels in all the four subtypes of adenosine receptors were increased 2-3 fold in the day 3 specimens and back to normal at day 7. Western blot demonstrated that A1AR, A2AAR, and A3AR expression increased 1.5 to 2 fold at day 3 and day 7 following Iodixanol injection. A2BAR baseline expression was low in normal physiological conditions and no significant change was detected by Western blot. Conclusions: Iodixanol significantly increases adenosine receptors gene expression in mice. This suggests that adenosine receptors may play a role in the development of CIN.展开更多
BACKGROUND Octreotide is widely used for the treatment of acromegaly,neuroendocrine tumors,and secretory diarrhea.However,long-term octreotide treatment can increase the incidence of gallstones.Vicarious contrast medi...BACKGROUND Octreotide is widely used for the treatment of acromegaly,neuroendocrine tumors,and secretory diarrhea.However,long-term octreotide treatment can increase the incidence of gallstones.Vicarious contrast medium excretion(VCME)through the hepatobiliary system is well known.However,few studies have reported octreotide-induced acute gallstones following VCME.CASE SUMMARY A 69-year-old man presented with left lower back pain and hematuria caused by a fall.The patient had a history of polycystic kidney disease.VCME occurred following renal artery embolization for a ruptured polycystic kidney.After 5 d of treatment with octreotide,the patient developed acute gallstones and intrahepatic cholestasis which further induced pancreatitis and cholangitis.He was discharged after hemodialysis,antibiotics,and supportive treatments.CONCLUSION For patients with a high-risk of VCME,octreotide should be cautiously administered and carefully monitored.展开更多
Background: Percutaneous coronary intervention is now the best way of management of acute coronary syndrome (ACS). Contrast induced nephropathy is a serious complication and greatly dependent on several factors. It is...Background: Percutaneous coronary intervention is now the best way of management of acute coronary syndrome (ACS). Contrast induced nephropathy is a serious complication and greatly dependent on several factors. It is still unclear whether the vascular access migrates CIN risk. Objective: To study the impact of Radial Access (RA) compared with Femoral Access (FA) on developing contrast-induced nephropathy (CIN) in patients undergoing invasive management of acute coronary syndrome (ACS). Methods: Sixty patients eligible for invasive management of ACS at cardiology department (Menoufia University hospital and National Heart Institute) were randomized into two groups. Group I: included 30 patients with femoral approach and Group II: included 30 patients with radial approach. The occurrence of CIN estimated by KDIGO definition (absolute increase in serum creatinine (SCr) by ≥0.5 mg/dl within 48 hours;or increase in SCr to ≥25% of baseline) was estimated in both groups. Results: Only 9 patients (15%) developed CIN, 5 patients (55.6%) of them underwent PCI through FA without statistically significant difference between the two approaches.Conclusion: CIN is considered a potential complication of percutaneous coronary intervention (PCI). Our study did not show the preference of using an approach over the other.展开更多
The risk of contrast-induced nephropathy(CIN) in renal transplant recipients is increased in diabetics, patients with impaired basal kidney function, patients in shock, patients presenting with acute emergency and in ...The risk of contrast-induced nephropathy(CIN) in renal transplant recipients is increased in diabetics, patients with impaired basal kidney function, patients in shock, patients presenting with acute emergency and in old age recipients. Approximately one-third of all hospitalized patients with acute kidney injury is attributed to CIN. In the United States, it is the third leading cause of hospital-acquired renal failure. Therefore, efforts should be directed to minimize CIN-related morbidity and mortality as well as to shorten hospital stay. While the role of peri-procedural prophylactic hydration with saline is unequivocal; the use of acetyl cysteine is not based on robust evidence. The utility of theophylline, aminophylline, calcium channel blockers, natriuretic peptide, and diuretics does not have proven role in attenuating CIN incidence. We aim to analyze the evidence for using various protocols in published literature to limit CIN-associated morbidity and mortality, particularly during surveillance of the renal allograft survival.展开更多
AIM To evaluate the feasibility of reducing the dose of iodinated contrast agent in computed tomography pulmonary angiography(CTPA). METHODS One hundred and twenty-seven patients clinically suspected of having pulmona...AIM To evaluate the feasibility of reducing the dose of iodinated contrast agent in computed tomography pulmonary angiography(CTPA). METHODS One hundred and twenty-seven patients clinically suspected of having pulmonary embolism underwent spiral CTPA, out of whom fifty-seven received 75 mL and the remaining seventy a lower dose of 60 mL of contrast agent. Both doses were administered in a multiphasic injection. A minimum opacification threshold of 250 Hounsfield units(HU) in the main pulmonary artery is used for assessing the technical adequacy of the scans. RESULTS Mean opacification was found to be positively correlated to patient age(Pearson's correlation 0.4255, P < 0.0001) and independent of gender(male:female, 425.6 vs 450.4,P = 0.34). When age is accounted for, the study and control groups did not differ significantly in their mean opacification in the main(436.8 vs 437.9, P = 0.48),left(416.6 vs 419.8, P = 0.45) or the right pulmonary arteries(417.3 vs 423.5, P = 0.40). The number of sub-optimally opacified scans(the mean opacification in the main pulmonary artery < 250 HU) did not differ significantly between the study and control groups(7 vs 10).CONCLUSION A lower dose of iodine contrast at 60 mL can be feasibly used in CTPA without resulting in a higher number of sub-optimally opacified scans.展开更多
AIM:To evaluate the feasibility of low contrast medium and radiation dose for hepatic computed tomography(CT) perfusion of rabbit VX2 tumor.METHODS:Eleven rabbits with hepatic VX2 tumor underwent perfusion CT scanning...AIM:To evaluate the feasibility of low contrast medium and radiation dose for hepatic computed tomography(CT) perfusion of rabbit VX2 tumor.METHODS:Eleven rabbits with hepatic VX2 tumor underwent perfusion CT scanning with a 24-h interval between a conventional tube potential(120 k Vp) protocol with 350 mg I/m L contrast medium and filtered back projection,and a low tube potential(80 k Vp) protocol with 270 mg I/m L contrast medium with iterative reconstruction.Correlation and agreement among perfusion parameters acquired by the conventional and low dose protocols were assessed for the viable tumor component as well as whole tumor.Image noise and tumor-to-liver contrast to noise ratio during arterial and portal venous phases were evaluated.RESULTS:A 38% reduction in contrast medium dose(360.1 ± 13.3 mg I/kg vs 583.5 ± 21.5 mg I/kg,P < 0.001) and a 73% decrease in radiation dose(1898.5 m Gy·cm vs 6951.8 m Gy·cm) were observed.Interestingly,there was a strong positive correlation in hepatic arterial perfusion(r = 0.907,P < 0.001;r = 0.879,P < 0.001),hepatic portal perfusion(r = 0.819,P = 0.002;r = 0.831,P = 0.002),and hepatic blood flow(r = 0.945,P < 0.001;r = 0.930,P < 0.001) as well as a moderate correlation in hepatic perfusion index(r = 0.736,P = 0.01;r = 0.636,P = 0.035) between the low dose protocol with iterative reconstruction and the conventional protocol for the viable tumor component and the whole tumor.These two imaging protocols provided a moderate but acceptable agreement for perfusion parameters and similar tumorto-liver CNR during arterial and portal venous phases(5.63 ± 2.38 vs 6.16 ± 2.60,P = 0.814;4.60 ± 1.27 vs 5.11 ± 1.74,P = 0.587).CONCLUSION:Compared with the conventional protocol,low contrast medium and radiation dose with iterative reconstruction has no significant influence on hepatic perfusion parameters for rabbits VX2 tumor.展开更多
Manganese compound with evident toxicity is widely employed as the contrast medium for clinicalexaminations such as magnetic resonance imaging(MRI).In the present work,a feasible way with the applica-tion of vacuum im...Manganese compound with evident toxicity is widely employed as the contrast medium for clinicalexaminations such as magnetic resonance imaging(MRI).In the present work,a feasible way with the applica-tion of vacuum impregnation and rotary evaporation was proposed to introduce manganese chloride hydrate intothe inner cavities of template - synthesized carbon nanotubes(CNTs),and then a process of alkali treatmentwas used to liberate the loaded CNTs from the template.It is notable that the alkali attack in the presence ofresidual oxygen also resulted in a series of changes in chemical compositions of guest substances,and the ulti-mate compound of manganese was found to be manganese oxide(Mn3O4) by X-ray diffraction and transmissionelectron microscopy.Determinations of energy dispersive spectrum under scanning electron microscopy showeda high-content filling(more than 50 wt%) of Mn3O4 in the loaded CNTs.This work developed a feasible andconvenient way for the encapsulation of guest substances to reduce bio-toxic effects.展开更多
Recent advances in medical sciences, especially in imaging, have dramatically increased the use of contrast agents. The constantly changing nature of medicine and the availability of new information, such as new pharm...Recent advances in medical sciences, especially in imaging, have dramatically increased the use of contrast agents. The constantly changing nature of medicine and the availability of new information, such as new pharmaceutical formulations, have necessitated periodic revisions and drafting of new guidelines for the safe use of intravenous contrast agents in radiology. This study examined the majority of guidelines, articles, and authoritative references available on the use of intravenous contrast agents in adults to reduce the risk of contrast-induced nephropathy. The search engines of PubMed, Web of Science, Scopus, and Google Scholar were used, and relevant English articles cited at least twice between 1979 and 2014 were studied. Review of the collected papers showed no consensus among them for guidelines on the incidence of contrast-induced nephropathy in patients at risk. Different formulas were used to calculate estimated glomerular filtration rate, which could be problematic in some cases. Further studies are needed for unification of existing guidelines.展开更多
Objective To evaluate the feasibility of using a low concentration of contrast medium(Visipaque 270 mg I/m L), low tube voltage, and an advanced image reconstruction algorithm in head and neck computed tomography angi...Objective To evaluate the feasibility of using a low concentration of contrast medium(Visipaque 270 mg I/m L), low tube voltage, and an advanced image reconstruction algorithm in head and neck computed tomography angiography(CTA).Methods Forty patients(22 men and 18 women; average age 48.7 ± 14.25 years; average body mass index 23.9 ± 3.7 kg/m2) undergoing CTA for suspected vascular diseases were randomly assigned into two groups. Group A(n = 20) was administered 370 mg I/m L contrast medium, and group B(n = 20) was administered 270 mg I/m L contrast medium. Both groups were administered at a rate of 4.8 m L/s and an injection volume of 0.8 m L/kg. Images of group A were obtained with 120 k Vp and filtered back projection(FBP) reconstruction, whereas images of group B were obtained with 80 k Vp and 80% adaptive iterative statistical reconstruction algorithm(ASi R). The CT values and standard deviations of intracranial arteries and image noise on the corona radiata were measured to calculate the contrast-to-noise ratio(CNR) and signal-to-noise ratio(SNR). The beam-hardening artifacts(BHAs) around the skull base were calculated. Two readers evaluated the image quality with volume rendered images using scores from 1 to 5. The values between the two groups were statistically compared.Results The mean CT value of the intracranial arteries in group B was significantly higher than that in group A(P < 0.001). The CNR and SNR values in group B were also statistically higher than those in group A(P < 0.001). Image noise and BHAs were not significantly different between the two groups. The image quality score of VR images of in group B was significantly higher than that in group A(P = 0.001). However, the quality scores of axial enhancement images in group B became significantly smaller than those in group A(P< 0.001). The CT dose index volume and dose-length product were decreased by 63.8% and 64%, respectively, in group B(P < 0.001 for both).Conclusion Visipaque combined with 80 k Vp and 80% ASi R provided similar image quality in intracranial CTA with 64% radiation dose reduction compared with the use of Iopamidol, 120 k Vp, and FBP reconstruction.展开更多
Purpose: The purpose of this retrospective study was to assess the incidence and the risk factors of contrast-induced nephropathy (CIN) following transcatheter arterial chemoembolization (TACE) in patients with hepato...Purpose: The purpose of this retrospective study was to assess the incidence and the risk factors of contrast-induced nephropathy (CIN) following transcatheter arterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC). Materials and Methods: We performed a retrospective review of 186 sessions of TACE in 122 patients with HCC. We examined the incidence and factors associated with risk of CIN, defined as an increase of at least 0.5 mg/dl (44.2 μmol/l) or 25% of the baseline serum creatinine level between 48 and 72 hours after TACE. Results: CIN developed in 14 (7.5%) of the 186 sessions after TACE. A univariate analysis showed that the Child-Pugh class B or C [10/14 (71%) vs. 70/172 (41%), P = 0.046], a low albumin level (3.0 ± 0.5 vs. 3.4 ± 0.6, P = 0.018), and a low hemoglobin level (10.6 ± 2.0 vs. 11.8 ± 2.0, P = 0.035) were significantly associated with the development of CIN. Multivariate analysis revealed that the hemoglobin value was associated with CIN [odds ratio (OR) 1.6;P = 0.038]. Conclusions: CIN after TACE is closely associated with the severity of liver cirrhosis, and with low levels of albumin and hemoglobin. Effective preventive methods remain to be considered in patients with HCC and advanced LC who are undergoing TACE.展开更多
BACKGROUND Many imaging methods such as ultrasonography,computed tomography(CT),magnetic resonance imaging,and endoscopy are used to identify the problems or complications that occur in the perioperative period and to...BACKGROUND Many imaging methods such as ultrasonography,computed tomography(CT),magnetic resonance imaging,and endoscopy are used to identify the problems or complications that occur in the perioperative period and to determine the appropriate therapeutic approach.Specialists at surgical clinics and intensive care units sometimes need diagnostic procedures that can give quick results or reveal unexpected results.In particular,rapid on-site evaluation of patients followed under intensive care conditions has several advantages.AIM To determine the problems developing in patients in the perioperative period by contrast-enhanced abdominal X-ray(CE-AXR),revealing their current status or defining the effectiveness of CE-AXR.METHODS The files of the patients who underwent hepatopancreatobiliary or upper gastrointestinal surgery,whose CE-AXR film was taken,were reviewed retrospectively.Abdominal X-ray radiographs taken after ingestion of a watersoluble contrast agent(iohexol,300 mg,50 cc vial)and its application in a drain,nasogastric tube,or stent were evaluated.The contribution of the data obtained in patients who underwent CE-AXR to the diagnosis,follow-up,and treatment processes and the effectiveness of the application were investigated.RESULTS CE-AXR was applied to 131 patients in our clinic,most of whom underwent hepatopancreatobiliary or upper gastrointestinal surgery.It was determined that the data obtained from CE-AXR films taken in 98(74.8%)of the patients contributed to the diagnosis,treatment,and follow-up expectations and positively affected the clinical processes.CONCLUSION CE-AXR is a simple procedure that can be applied anywhere,especially in intensive care patients and at bedside,with a portable X-ray device.The simplicity of the procedure,less radiation exposure for the patients,less time wastage,reduction in the CT and endoscopy procedure burden and costs,quick results,rapid assessment of the situation,and enabling the monitoring of processes with repetitive procedures are important advantages.X-rays taken will be useful in terms of being a reference value during the follow-up period of the patient and determining the situation in medicolegal processes.展开更多
文摘Contrast medium induced nephropathy is the third most common cause of renal failure for inpatients and represents the 10% of all acute kidney injury occurring during hospital-stay. It is associated with prolonged hospitalization, cost increase and, above all, an unfavourable short- and long-term prognosis. Here, the authors discuss about the contrast medium induced nephropathy prevention strategies, from the identification of patients at risk and drugs potentially nephrotoxic, to the hydration with possible administration of drugs that appeared to be, in some contexts, nephron-protective, and finally we analyze the radiological procedure aimed at the correct choice of type and administration modality of the contrast medium according to current literature.
基金Supported by The Kaohsiung Veterans General Hospital,Grant No. VGHKS100-032 (in part)
文摘Radiocontrast-induced nephropathy(RCIN) is an acute and severe complication after coronary angiography,particularly for patients with pre-existing chronic kidney disease(CKD).It has been associated with both short-and long-term adverse outcomes,including the need for renal replacement therapy,increased length of hospital stay,major cardiac adverse events,and mortality.RCIN is generally defined as an increase in serum creatinine concentration of 0.5 mg/dL or 25%above baseline within 48 h after contrast administration.There is no effective therapy once injury has occurred,therefore,prevention is the cornerstone for all patients at risk for acute kidney injury(AKI).There is a small but growing body of evidence that prevention of AKI is associated with a reduction in later adverse outcomes.The optimal strategy for preventing RCIN has not yet been established.This review discusses the principal risk factors for RCIN,evaluates and summarizes the evidence for RCIN prophylaxis,and proposes recommendations for preventing RCIN in CKD patients undergoing coronary angiography.
文摘Objective: Contrast induced nephropathy (CIN) is the third leading cause of hospital acquired renal failure. The mechanism of CIN is not fully understood. The objectives of this study were to investigate the expression changes of the four subtypes of adenosine receptors (A1AR, A2AAR, A2BAR, and A3AR) following administration of contrast media in mice. Methods: C57BL/6J mice were randomized into treatment and control groups. Iodixanol (IDX) was administered to two treatment groups through retroorbital injection at two different dosages, 0.75 gI/kg and 2.75 gI/kg. Phosphate buffered saline (PBS) was given to the control group. Mice kidneys were harvested at day 3 and day 7 after Iodixanol administration. Kidney injuries and function were evaluated according to Hematoxylin and eosin stain, Ki67 protein expression, and TUNEL assay of paraffin embedded kidney sections, and plasma creatinine assay. RNA and protein were extracted from the kidney specimens. A1AR, A2AAR, A2BAR, and A3AR RNA and protein level of the samples were assessed using qRT-PCR and Western blotting, with GAPDH as an endogenous control. Results: H&E staining showed no significant histopathology injuries after Iodixanol administration. No evidence of kidney injury and functional impairment was found. However, there was an increased number of A1AR, A2AAR, A2BAR, and A3AR RNA transcripts detected in the kidney 3 days after Iodixanol injection. The RNA levels in all the four subtypes of adenosine receptors were increased 2-3 fold in the day 3 specimens and back to normal at day 7. Western blot demonstrated that A1AR, A2AAR, and A3AR expression increased 1.5 to 2 fold at day 3 and day 7 following Iodixanol injection. A2BAR baseline expression was low in normal physiological conditions and no significant change was detected by Western blot. Conclusions: Iodixanol significantly increases adenosine receptors gene expression in mice. This suggests that adenosine receptors may play a role in the development of CIN.
文摘BACKGROUND Octreotide is widely used for the treatment of acromegaly,neuroendocrine tumors,and secretory diarrhea.However,long-term octreotide treatment can increase the incidence of gallstones.Vicarious contrast medium excretion(VCME)through the hepatobiliary system is well known.However,few studies have reported octreotide-induced acute gallstones following VCME.CASE SUMMARY A 69-year-old man presented with left lower back pain and hematuria caused by a fall.The patient had a history of polycystic kidney disease.VCME occurred following renal artery embolization for a ruptured polycystic kidney.After 5 d of treatment with octreotide,the patient developed acute gallstones and intrahepatic cholestasis which further induced pancreatitis and cholangitis.He was discharged after hemodialysis,antibiotics,and supportive treatments.CONCLUSION For patients with a high-risk of VCME,octreotide should be cautiously administered and carefully monitored.
文摘Background: Percutaneous coronary intervention is now the best way of management of acute coronary syndrome (ACS). Contrast induced nephropathy is a serious complication and greatly dependent on several factors. It is still unclear whether the vascular access migrates CIN risk. Objective: To study the impact of Radial Access (RA) compared with Femoral Access (FA) on developing contrast-induced nephropathy (CIN) in patients undergoing invasive management of acute coronary syndrome (ACS). Methods: Sixty patients eligible for invasive management of ACS at cardiology department (Menoufia University hospital and National Heart Institute) were randomized into two groups. Group I: included 30 patients with femoral approach and Group II: included 30 patients with radial approach. The occurrence of CIN estimated by KDIGO definition (absolute increase in serum creatinine (SCr) by ≥0.5 mg/dl within 48 hours;or increase in SCr to ≥25% of baseline) was estimated in both groups. Results: Only 9 patients (15%) developed CIN, 5 patients (55.6%) of them underwent PCI through FA without statistically significant difference between the two approaches.Conclusion: CIN is considered a potential complication of percutaneous coronary intervention (PCI). Our study did not show the preference of using an approach over the other.
文摘The risk of contrast-induced nephropathy(CIN) in renal transplant recipients is increased in diabetics, patients with impaired basal kidney function, patients in shock, patients presenting with acute emergency and in old age recipients. Approximately one-third of all hospitalized patients with acute kidney injury is attributed to CIN. In the United States, it is the third leading cause of hospital-acquired renal failure. Therefore, efforts should be directed to minimize CIN-related morbidity and mortality as well as to shorten hospital stay. While the role of peri-procedural prophylactic hydration with saline is unequivocal; the use of acetyl cysteine is not based on robust evidence. The utility of theophylline, aminophylline, calcium channel blockers, natriuretic peptide, and diuretics does not have proven role in attenuating CIN incidence. We aim to analyze the evidence for using various protocols in published literature to limit CIN-associated morbidity and mortality, particularly during surveillance of the renal allograft survival.
文摘AIM To evaluate the feasibility of reducing the dose of iodinated contrast agent in computed tomography pulmonary angiography(CTPA). METHODS One hundred and twenty-seven patients clinically suspected of having pulmonary embolism underwent spiral CTPA, out of whom fifty-seven received 75 mL and the remaining seventy a lower dose of 60 mL of contrast agent. Both doses were administered in a multiphasic injection. A minimum opacification threshold of 250 Hounsfield units(HU) in the main pulmonary artery is used for assessing the technical adequacy of the scans. RESULTS Mean opacification was found to be positively correlated to patient age(Pearson's correlation 0.4255, P < 0.0001) and independent of gender(male:female, 425.6 vs 450.4,P = 0.34). When age is accounted for, the study and control groups did not differ significantly in their mean opacification in the main(436.8 vs 437.9, P = 0.48),left(416.6 vs 419.8, P = 0.45) or the right pulmonary arteries(417.3 vs 423.5, P = 0.40). The number of sub-optimally opacified scans(the mean opacification in the main pulmonary artery < 250 HU) did not differ significantly between the study and control groups(7 vs 10).CONCLUSION A lower dose of iodine contrast at 60 mL can be feasibly used in CTPA without resulting in a higher number of sub-optimally opacified scans.
基金National Natural Science Foundation of China,No.NSFC 81171389Key Program of Basic Research from Shanghai Municipal Science and Technology Commission,No.12JC1406500the Program of Shanghai Municipal Health Outstanding Discipline Leader,No.XBR 2013110
文摘AIM:To evaluate the feasibility of low contrast medium and radiation dose for hepatic computed tomography(CT) perfusion of rabbit VX2 tumor.METHODS:Eleven rabbits with hepatic VX2 tumor underwent perfusion CT scanning with a 24-h interval between a conventional tube potential(120 k Vp) protocol with 350 mg I/m L contrast medium and filtered back projection,and a low tube potential(80 k Vp) protocol with 270 mg I/m L contrast medium with iterative reconstruction.Correlation and agreement among perfusion parameters acquired by the conventional and low dose protocols were assessed for the viable tumor component as well as whole tumor.Image noise and tumor-to-liver contrast to noise ratio during arterial and portal venous phases were evaluated.RESULTS:A 38% reduction in contrast medium dose(360.1 ± 13.3 mg I/kg vs 583.5 ± 21.5 mg I/kg,P < 0.001) and a 73% decrease in radiation dose(1898.5 m Gy·cm vs 6951.8 m Gy·cm) were observed.Interestingly,there was a strong positive correlation in hepatic arterial perfusion(r = 0.907,P < 0.001;r = 0.879,P < 0.001),hepatic portal perfusion(r = 0.819,P = 0.002;r = 0.831,P = 0.002),and hepatic blood flow(r = 0.945,P < 0.001;r = 0.930,P < 0.001) as well as a moderate correlation in hepatic perfusion index(r = 0.736,P = 0.01;r = 0.636,P = 0.035) between the low dose protocol with iterative reconstruction and the conventional protocol for the viable tumor component and the whole tumor.These two imaging protocols provided a moderate but acceptable agreement for perfusion parameters and similar tumorto-liver CNR during arterial and portal venous phases(5.63 ± 2.38 vs 6.16 ± 2.60,P = 0.814;4.60 ± 1.27 vs 5.11 ± 1.74,P = 0.587).CONCLUSION:Compared with the conventional protocol,low contrast medium and radiation dose with iterative reconstruction has no significant influence on hepatic perfusion parameters for rabbits VX2 tumor.
文摘Manganese compound with evident toxicity is widely employed as the contrast medium for clinicalexaminations such as magnetic resonance imaging(MRI).In the present work,a feasible way with the applica-tion of vacuum impregnation and rotary evaporation was proposed to introduce manganese chloride hydrate intothe inner cavities of template - synthesized carbon nanotubes(CNTs),and then a process of alkali treatmentwas used to liberate the loaded CNTs from the template.It is notable that the alkali attack in the presence ofresidual oxygen also resulted in a series of changes in chemical compositions of guest substances,and the ulti-mate compound of manganese was found to be manganese oxide(Mn3O4) by X-ray diffraction and transmissionelectron microscopy.Determinations of energy dispersive spectrum under scanning electron microscopy showeda high-content filling(more than 50 wt%) of Mn3O4 in the loaded CNTs.This work developed a feasible andconvenient way for the encapsulation of guest substances to reduce bio-toxic effects.
文摘Recent advances in medical sciences, especially in imaging, have dramatically increased the use of contrast agents. The constantly changing nature of medicine and the availability of new information, such as new pharmaceutical formulations, have necessitated periodic revisions and drafting of new guidelines for the safe use of intravenous contrast agents in radiology. This study examined the majority of guidelines, articles, and authoritative references available on the use of intravenous contrast agents in adults to reduce the risk of contrast-induced nephropathy. The search engines of PubMed, Web of Science, Scopus, and Google Scholar were used, and relevant English articles cited at least twice between 1979 and 2014 were studied. Review of the collected papers showed no consensus among them for guidelines on the incidence of contrast-induced nephropathy in patients at risk. Different formulas were used to calculate estimated glomerular filtration rate, which could be problematic in some cases. Further studies are needed for unification of existing guidelines.
文摘Objective To evaluate the feasibility of using a low concentration of contrast medium(Visipaque 270 mg I/m L), low tube voltage, and an advanced image reconstruction algorithm in head and neck computed tomography angiography(CTA).Methods Forty patients(22 men and 18 women; average age 48.7 ± 14.25 years; average body mass index 23.9 ± 3.7 kg/m2) undergoing CTA for suspected vascular diseases were randomly assigned into two groups. Group A(n = 20) was administered 370 mg I/m L contrast medium, and group B(n = 20) was administered 270 mg I/m L contrast medium. Both groups were administered at a rate of 4.8 m L/s and an injection volume of 0.8 m L/kg. Images of group A were obtained with 120 k Vp and filtered back projection(FBP) reconstruction, whereas images of group B were obtained with 80 k Vp and 80% adaptive iterative statistical reconstruction algorithm(ASi R). The CT values and standard deviations of intracranial arteries and image noise on the corona radiata were measured to calculate the contrast-to-noise ratio(CNR) and signal-to-noise ratio(SNR). The beam-hardening artifacts(BHAs) around the skull base were calculated. Two readers evaluated the image quality with volume rendered images using scores from 1 to 5. The values between the two groups were statistically compared.Results The mean CT value of the intracranial arteries in group B was significantly higher than that in group A(P < 0.001). The CNR and SNR values in group B were also statistically higher than those in group A(P < 0.001). Image noise and BHAs were not significantly different between the two groups. The image quality score of VR images of in group B was significantly higher than that in group A(P = 0.001). However, the quality scores of axial enhancement images in group B became significantly smaller than those in group A(P< 0.001). The CT dose index volume and dose-length product were decreased by 63.8% and 64%, respectively, in group B(P < 0.001 for both).Conclusion Visipaque combined with 80 k Vp and 80% ASi R provided similar image quality in intracranial CTA with 64% radiation dose reduction compared with the use of Iopamidol, 120 k Vp, and FBP reconstruction.
文摘Purpose: The purpose of this retrospective study was to assess the incidence and the risk factors of contrast-induced nephropathy (CIN) following transcatheter arterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC). Materials and Methods: We performed a retrospective review of 186 sessions of TACE in 122 patients with HCC. We examined the incidence and factors associated with risk of CIN, defined as an increase of at least 0.5 mg/dl (44.2 μmol/l) or 25% of the baseline serum creatinine level between 48 and 72 hours after TACE. Results: CIN developed in 14 (7.5%) of the 186 sessions after TACE. A univariate analysis showed that the Child-Pugh class B or C [10/14 (71%) vs. 70/172 (41%), P = 0.046], a low albumin level (3.0 ± 0.5 vs. 3.4 ± 0.6, P = 0.018), and a low hemoglobin level (10.6 ± 2.0 vs. 11.8 ± 2.0, P = 0.035) were significantly associated with the development of CIN. Multivariate analysis revealed that the hemoglobin value was associated with CIN [odds ratio (OR) 1.6;P = 0.038]. Conclusions: CIN after TACE is closely associated with the severity of liver cirrhosis, and with low levels of albumin and hemoglobin. Effective preventive methods remain to be considered in patients with HCC and advanced LC who are undergoing TACE.
文摘BACKGROUND Many imaging methods such as ultrasonography,computed tomography(CT),magnetic resonance imaging,and endoscopy are used to identify the problems or complications that occur in the perioperative period and to determine the appropriate therapeutic approach.Specialists at surgical clinics and intensive care units sometimes need diagnostic procedures that can give quick results or reveal unexpected results.In particular,rapid on-site evaluation of patients followed under intensive care conditions has several advantages.AIM To determine the problems developing in patients in the perioperative period by contrast-enhanced abdominal X-ray(CE-AXR),revealing their current status or defining the effectiveness of CE-AXR.METHODS The files of the patients who underwent hepatopancreatobiliary or upper gastrointestinal surgery,whose CE-AXR film was taken,were reviewed retrospectively.Abdominal X-ray radiographs taken after ingestion of a watersoluble contrast agent(iohexol,300 mg,50 cc vial)and its application in a drain,nasogastric tube,or stent were evaluated.The contribution of the data obtained in patients who underwent CE-AXR to the diagnosis,follow-up,and treatment processes and the effectiveness of the application were investigated.RESULTS CE-AXR was applied to 131 patients in our clinic,most of whom underwent hepatopancreatobiliary or upper gastrointestinal surgery.It was determined that the data obtained from CE-AXR films taken in 98(74.8%)of the patients contributed to the diagnosis,treatment,and follow-up expectations and positively affected the clinical processes.CONCLUSION CE-AXR is a simple procedure that can be applied anywhere,especially in intensive care patients and at bedside,with a portable X-ray device.The simplicity of the procedure,less radiation exposure for the patients,less time wastage,reduction in the CT and endoscopy procedure burden and costs,quick results,rapid assessment of the situation,and enabling the monitoring of processes with repetitive procedures are important advantages.X-rays taken will be useful in terms of being a reference value during the follow-up period of the patient and determining the situation in medicolegal processes.
