OBJECTIVE: To examine the potential of intravoxel incoherent motion (IVIM) and blood oxygen level-dependent (BOLD) magnetic resonance imaging for detecting renal changes after iodinated contrast-induced acute kidney injury (CI-AKI) development in a diabetic rabbit model. MATERIALS AND METHODS: Sixty-two rabbits were randomized into 2 groups: diabetic rabbits with the contrast agent (DCA) and healthy rabbits with the contrast agent (NCA). In each group, 6 rabbits underwent IVIM and BOLD imaging at 1 hour, 1 day, 2 days, 3 days, and 4 days after an iohexol injection while 5 rabbits were selected to undergo blood and histological examinations at these specific time points. Iohexol was administrated at a dose of 2.5 g I/kg of body weight. Further, the apparent transverse relaxation rate (R2*), average pure molecular diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) were calculated. RESULTS: The D and f values of the renal cortex (CO) and outer medulla (OM) were significantly decreased compared to baseline values in the 2 groups 1 day after the iohexol injection (p < 0.05). A marked reduction in the D* values for both the CO and OM was also observed after 1 hour in each group (p < 0.05). In the OM, a persistent elevation of the R2* was detected for 4 days in the DCA group (p < 0.05). Histopathological changes were prominent, and the pathological features of CI-AKI aggravated in the DCA group until day 4. The D, f, and R2* values significantly correlated with the histological damage scores, hypoxia-inducible transcription factor-1α expression scores, and serum creatinine levels. CONCLUSION: A combination of IVIM and BOLD imaging may serve as a noninvasive method for detecting and monitoring CI-AKI in the early stages in the diabetic kidney.
Acute Kidney Injury ; Body Weight ; Creatinine ; Diffusion ; Iohexol ; Kidney ; Magnetic Resonance Imaging ; Methods ; Oxygen ; Perfusion ; Rabbits ; Relaxation ; Vascular Endothelial Growth Factor A

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.
Abdomen ; Animals ; Aorta ; Artifacts ; Dogs ; Humans ; Iohexol ; Liver ; Portal Vein ; Tomography, X-Ray Computed

This study was performed to evaluate the feasibility of ultrasound-guided computed tomography (CT) cholecystography and to establish an optimal protocol. In 8 healthy beagles, CT cholecystography was conducted using four contrast formulas; two dilution ratios (1:1 vs. 1:3) and two total volumes (8 mL vs. 16 mL) of 300 mgI/kg iohexol after ultrasound-guided percutaneous contrast injection into the gallbladder. CT images were obtained at 3, 10, and 30 min after injection and assessed qualitatively and quantitatively. For all contrast formulas, CT cholecystography showed the gallbladder and the intra- and extrahepatic bile ducts. The volume of the gallbladder and size of bile duct were significantly larger when using a volume of 16 mL iohexol than an 8 mL volume regardless of the dilution ratio. The distinction between the common bile duct and duodenum, the filling of the gallbladder, and the patency of bile duct were effectively assessed using a 16 mL volume of contrast agent with either dilution ratio. Beam-hardening artifacts deteriorated CT image quality for visualizing the biliary system when using the dilution ratio of 1:1. Patency of the bile tract could be easily evaluated using a curvilinear planar reconstruction. There was no significant difference in CT scan time among the different conditions. Minor leakage of contrast agent temporarily occurred after contrast injection in 30% of 32 sets of CT cholecystography. Ultrasound-guided percutaneous cholecystography can visualize both gallbladder and biliary tract with minimal artifacts using a contrast agent volume of 16 mL with a 1:3 dilution ratio.
Animals ; Artifacts ; Bile ; Bile Ducts ; Bile Ducts, Extrahepatic ; Biliary Tract ; Cholecystography ; Common Bile Duct ; Contrast Media ; Dogs ; Duodenum ; Gallbladder ; Iohexol ; Tomography, X-Ray Computed

Acute generalized exanthematous pustulosis (AGEP) is rarely caused by radiocontrast media (RCM). The role of skin tests for the diagnosis and evaluation of cross-reactivity in a delayed type of RCM-induced hypersensitivity have yet to be determined. Here, we report a case of iodixanol-induced AGEP where we safely administered alternative RCM using patch tests. A 44-year-old woman had coronary artery angiography (CAG) for the evaluation of ischemic heart disease. She was on regular hemodialysis because of end-stage renal disease. She was given iodixanol (Visipaque) during CAG. Approximately 1 day after CAG, she developed AGEP. The patient was rehospitalized for CAG again after 1 year. We performed skin tests to choose safe alternative RCM. Intradermal tests with iodixanol, iohexol (Bonorex) and Iopamidol (Pamiray) showed negative responses. Patch tests showed a positive response to iodixanol, equivocal to iohexol, and negative to Iopamidol. We finally chose Iopamidol and performed CAG successfully without any adverse reaction. Patch tests may be a useful tool for the diagnosis and choice of safe alternatives in RCM-induced delayed-type hypersensitivity reactions such as AGEP.
Acute Generalized Exanthematous Pustulosis* ; Adult ; Angiography ; Contrast Media* ; Coronary Vessels ; Diagnosis ; Female ; Humans ; Hypersensitivity ; Intradermal Tests ; Iohexol ; Iopamidol ; Kidney Failure, Chronic ; Myocardial Ischemia ; Patch Tests* ; Renal Dialysis ; Skin Tests

Objective To evaluate the feasibility of peripheral artery CT angiography (CTA)under 70 kV with 50 ml contrast medium on the third-generation dual-source CT. Methods Totally 82 patients who were equally randomized into two groups:70 kV group:the scan was performed under 70 kV tube voltage+50 ml iopromide on the third-generation dual-source CT;and 100 kV group:the scan was performed under 100 kV tube voltage+90 ml iopromide on the second-generation dual-source CT. The CT number of abdominal aorta,bilateral common iliac arteries,common femoral arteries,superficial femoral arteries,popliteal arteries and arteries of the calf were measured and contrast to noise ratio(CNR),signal to noise ratio(SNR)were calculated. The image quality was compared between these two groups. Results The dose-length product was (195.8±46.9)mGy·cm in 70 kV group,which was significantly lower than that in 100 kV group (461.6±57.9)mGy·cm,and was decreased by 57% (t=-22.848,P=0.000). Compared with the 100 kV group,the CT number of the proximal abdominal aorta in 70 kV group was significantly lower(t=-2.502,P=0.014),while the CT number of superficial femoral arteries (t=3.053,P=0.003)and popliteal arteries (t=4.013,P=0.000)was much higher in 70 kV group. SNR and CNR of proximal abdominal aorta,distal abdominal aorta,bilateral common iliac arteries,common femoral arteries,superficial femoral arteries,popliteal arteries and arteries of the calf were significantly lower in 70 kV group than those in 100 kV group (all P<0.05). The artifacts in abdominal aorta (t=2.893,P=0.000)and feet arteries (t=3.776,P=0.000)were higher in 70 kV group than those in 100 kV group,the enhancement of abdominal aorta (t=-1.000,P=0.002)and feet arteries (t=2.893,P=0.010)were lower in 70 kV group,the enhancement of femoral-popliteal arteries (t=-1.000,P=0.000)and arteries of calf (t=4.261,P=0.000)were higher in 70 kV group. Compared with the 100 kV group,the image noise in aorta (t=2.048,P=0.044),femoral-popliteal arteries (t=8.370,P=0.000),arteries of the calf (t=8.315,P=0.000)and feet arteries (t=7.202,P=0.000)were higher in 70 kV group. Conclusion Compared to conventional scan protocol,using 70 kV tube voltage with 50 ml contrast medium to perform peripheral artery CTA can assure the image quality and meanwhile remarkably reduce the radiation dose and the use of contrast medium.
Aorta, Abdominal ; diagnostic imaging ; Arteries ; diagnostic imaging ; Artifacts ; Computed Tomography Angiography ; Contrast Media ; Humans ; Iohexol ; analogs & derivatives ; Leg ; blood supply ; Radiation Dosage ; Signal-To-Noise Ratio ; Tomography, X-Ray Computed

ObjectiveTo investigate the application value of Toshiba 320-row dynamic volumetric CT angiography in the diagnosis of venous erectile dysfunction (VED).

METHODSWe enrolled in this study 33 patients diagnosed with ED by audiovisual sexual stimulation screening in the outpatient department. Penile erection was induced in the patients by injection of 2 mg phentolamine plus 30 mg papaverine into the corpus cavernosum, followed by that of contrast agent of iobitridol through the vein and corpus cavernosum successively. Then 320-row dynamic volumetric CT angiography was performed and the images of the corpus cavernosum in the arterial and venous phases were collected and processed.

RESULTSDifferent degrees of abnormal venous drainage were observed in 29 of the patients, including 7 cases (24.1%) of back deep venous leakage, 6 cases (20.7%) of foot venous leakage, 3 cases (10.3%) of dorsal superficial venous leakage, 1 case (3.5%) of intervertebral venous leakage, 2 cases (6.9%) of cavernous venous leakage, and 10 cases (34.5%) of mixed venous leakage. Ten of the patients underwent surgery, dorsal deep penile vein ligation in 2 cases, dorsal deep vein embedding plus foot vein ligation in 4, and foot vein ligation in the other 4. Eight of the patients were followed up for 3－12 months post-operatively, during which 2 achieved obvious erectile improvement, while the other 6 gained normal penile erection.

CONCLUSIONSToshiba 320-row dynamic volumetric CT angiography is a reliable method for the diagnosis of VED, which displays the precise location of venous leakage for clinical treatment, with the advantages of clearer images, lower doses of contrast agent and radiation, and faster examination than X-ray penile angiography.

Adult ; Arteries ; diagnostic imaging ; Computed Tomography Angiography ; Contrast Media ; Drug Combinations ; Erectile Dysfunction ; diagnostic imaging ; Humans ; Injections ; Iohexol ; analogs & derivatives ; Ligation ; Male ; Middle Aged ; Papaverine ; administration & dosage ; Penile Erection ; Penis ; diagnostic imaging ; physiopathology ; Phentolamine ; administration & dosage ; Veins ; diagnostic imaging ; surgery

OBJECTIVE: The increasing use of imaging examinations such as computed tomography (CT) results in increased contrast media use, which increases contrast media-induced adverse reactions (AR). This study investigated the risk factors of ARs to nonionic iodinated contrast media. METHODS: This study evaluated patients who were administered iodinated contrast media during CT scanning in Yeouido St. Mary's Hospital in Seoul, Korea in 2012. Among the subjects, those with contrast media-induced ARs were classified as the AR group. The control group included individuals without ARs who were selected through simple random sampling. The effects of sex, age, contrast media type and dose, CT region, previous contrast media administration, allergy history, and comorbidity were analyzed in the AR and control groups. RESULTS: Multivariate logistic regression analyses were performed to evaluate the identified AR risk factors in 103 subjects in the AR group and 412 subjects in the control group. The results confirmed that the risk of developing ARs was significantly higher in females [odds ratio (OR): 2.206; 95% confidence interval (CI): 1.353-3.598], in individuals administered Iohexol (OR: 9.981; 95% CI: 2.361-42.193), in individuals with an allergy history (OR: 3.982; 95% CI: 1.742-9.101), and in individuals with comorbid asthma (OR: 6.619; 95% CI: 1.377-31.826). Most of the ARs were mild and immediate. CONCLUSION: In patients who were administered contrast media during CT scans, female gender, Iohexol use, allergy history, and asthma were risk factors for ARs. Therefore, special care is required for patients with such risk factors to prevent ARs.
Asthma ; Comorbidity ; Contrast Media* ; Female ; Humans ; Hypersensitivity ; Iohexol ; Korea ; Logistic Models ; Risk Factors* ; Seoul ; Tomography, X-Ray Computed

OBJECTIVETo evaluate the accuracy of plasma clearance of iohexol (PCio) for glomerular filtration rate (GFR) measurement in Chinese children with chronic kidney disease (CKD) and assess the feasibility of single-blood-sample method or dried capillary blood spots in determining the PCio.

METHODSTotally 45 CKD children were included,in whom the (99m) Technetium-diethylenetriaminepentaacetic acid ((99m)Tc-DTPA) plasma clearance and iohexol plasma clearance were simultaneously determined. Blood samples were obtained 2,4,and 5 hours after injection. In addition, we also evaluated the efficacy of single blood sample method and dried blood spots method in iohexol plasma clearance.

RESULTSForty-five CKD children completed the iohexol plasma clearance and thirty-six children completed the (99m)Tc-DTPA plasma clearance at the same time among them. Thirteen children finished the iohexol dried blood spot clearance. The correlation coefficient between (99m)Tc-DTPA plasma clearance and iohexol plasma clearance was 0.941 and the bias was (6.53 ± 11.6) ml/ (min·1.73 m²), and the intraclass correlation coefficient (ICC) was high (ICC=0.947). The correlation between iohexol single-sample plasma clearance and double samples was also strong (r=0.958), with the bias being (4.26 ± 9.06)ml/(min·1.73 m²) and the ICC being 0.970. The iohexol clearance by dried blood spots showed a good correlation with the serum iohexol clearance (r=0.950), with the bias still being small [(0.48 ± 10.89)ml/(min·1.73 m²)].

CONCLUSIONSIohexol plasma clearance has satisfactory agreement with (99m)Tc-DTPA plasma clearance and can be used as an ideal method to measure GFR in CKD children. The single-sample method and dried blood spots method make iohexol plasma clearance more convenient and practical.

Child ; Glomerular Filtration Rate ; Humans ; Iohexol ; Renal Insufficiency, Chronic ; Technetium Tc 99m Pentetate

Aortic Aneurysm, Thoracic ; complications ; diagnostic imaging ; Aortography ; Contrast Media ; adverse effects ; Coronary Artery Bypass ; Cross Infection ; diagnostic imaging ; Fatal Outcome ; Female ; Humans ; Iohexol ; adverse effects ; Kidney Failure, Chronic ; complications ; Male ; Middle Aged ; Postoperative Complications ; diagnostic imaging ; ST Elevation Myocardial Infarction ; surgery ; Sepsis ; etiology ; Stevens-Johnson Syndrome ; etiology ; Surgical Wound Dehiscence ; diagnostic imaging ; Tomography, X-Ray Computed

Although hypersensitivity reactions to iodinated contrast media (ICM) are uncommon, their clinical impacts are considerable because of their wide use and potential fatality. The best way to prevent ICM-induced hypersensitivity is to avoid re-exposure to the ICM. However, ICM use is inevitable in the evaluation of many diseases. A 64-year-old male with renal cell carcinoma presented with anaphylaxis after computed tomography (CT) using iohexol. Intradermal test results were positive to iohexol, iomeprol, and ioversol. The following 3 CT scans using the test-negative agents iopromide, iopamidol, and iobitridol still provoked hypersensitivity reactions despite premedication using intravenous antihistamine and corticosteroid. For the next step, iodixanol, a nonionic iso-osmolar dimer, was tested by intravenous graded challenges in addition to the intradermal skin test, which and was confirmed to be negative. The patient underwent CT scan using iodixanol after premedication with chlorpheniramine 4 mg and methylprednisolone 40 mg, and hypersensitivity reactions did not recur. We report a case of a patient showing hyper reactivity to multiple ICMs despite negative intradermal skin tests, who eventually underwent successful enhanced CT scans after choosing ICM by the graded challenge test.
Anaphylaxis* ; Carcinoma, Renal Cell ; Chlorpheniramine ; Contrast Media* ; Humans ; Hypersensitivity ; Intradermal Tests ; Iohexol ; Iopamidol ; Male ; Methylprednisolone ; Middle Aged ; Premedication ; Skin Tests ; Tomography, X-Ray Computed