The purpose of this study was to determine the morphological and dynamic features of normal pulmonary valve by using dual-source CT. Thirty patients who underwent dual-source CT angiography with right ventricular outflow tract well-opacified were enrolled. Ten phases of images were reconstructed at 10% R-R interval, and pulmonary valve area and pulmonary annular diameter were measured on all 10 phases. As the pulmonary valve opened, its orifice appeared as oval or proximate triangle. As the pulmonary valve closed, it appeared as "Y-shape". Pulmonary valve opened from 10% to 30% phases, with maximum pulmonary valve area of (4.74 +/- 0.69) cm2 in 10% phase. Pulmonary valve closed from 40% to 90% phases. Pulmonary annular diameter varied with cardiac cycle, with maximum pulmonary annular diameter of (2.36 +/- 0.24) cm in 0% phase and minimum pulmonary annular diameter of (1.82 +/- 0.32) cm in 40% phase (P < 0.001). The proximal phase for assessing pulmonary valve was 70% phase. Dual-source CT may evaluate the morphological and dynamic features of normal pulmonary valve.
Adult ; Female ; Humans ; Iohexol ; analogs & derivatives ; Male ; Middle Aged ; Pulmonary Valve ; anatomy & histology ; diagnostic imaging ; physiology ; Tomography, Spiral Computed ; methods

OBJECTIVE: To evaluate the nature and imaging appearance of incidental enhancing breast lesions detected on a routine contrast-enhanced chest CT. MATERIALS AND METHODS: Twenty-three patients with incidental enhancing breast lesions on contrast-enhanced chest CT were retrospectively reviewed. The breast lesions were reviewed by unenhanced and enhanced CT, and evaluated by observing the shapes, margins, enhancement patterns and backgrounds of breast lesions. A histopathologic diagnosis or long-term follow-up served as reference standard. RESULTS: Sixteen (70%) patients had malignant breast lesions and seven (30%) had benign lesions. In 10 patients, the breast lesions were exclusively detected on contrast-enhanced CT. Using unenhanced CT, breast lesions with fibroglandular backgrounds were prone to be obscured (p < 0.001). Incidental primary breast cancer showed an non-significant trend of a higher percentage irregular margin (p = 0.056). All of the four incidental breast lesions with non-mass-like enhancement were proven to be malignant. CONCLUSION: Routine contrast-enhanced chest CT can reveal sufficient details to allow for the detection of unsuspected breast lesions, in which some cases may be proven as malignant. An irregular margin of incidental enhancing breast lesion can be considered a suggestive sign of malignancy.
Aged ; Breast Diseases/radiography ; Breast Neoplasms/*radiography/secondary ; *Contrast Media ; Female ; Humans ; *Incidental Findings ; Iohexol/*analogs & derivatives/diagnostic use ; Middle Aged ; *Radiography, Thoracic ; *Tomography, X-Ray Computed

OBJECTIVE: To evaluate the effect of thin overlapping reconstruction on the attenuation of small (< or = 3 cm) renal cysts in the nephrographic phase of multidetector CT (MDCT). MATERIALS AND METHODS: We scanned a phantom kidney containing spheres of various sizes (10, 20, and 30 mm) using both 4- and 16-channel MDCT scanners, and reconstructed images with various slice thickness (T, mm) and intervals (I, mm). The attenuation increase (AI) was measured for each sphere in 240-HU diluted solution of contrast material and compared with the attenuation in 35-HU solution. RESULTS: On the 4-channel MDCT, thin overlapping reconstruction (T/I = 3/1, compared with 5/5) lowered the AI as much as 17 HU in the 10 mm-sphere and 6 HU in the 20 mm-sphere (p < 0.05). Thin slicing alone was also effective; however overlapping alone was not. On the 16-channel MDCT, AI in the 10 mm-sphere was significantly lower than on the 4-channel MDCT with T/I = 5/5 (p < 0.05), however thinner slicing or overlapping did not affect the attenuation significantly in all of the spheres. CONCLUSION: The effect of thin overlapping reconstruction on minimizing falsely elevated attenuation in the nephrographic phase was significant only in cysts < or =20 mm on the 4-channel MDCT.
Tomography, X-Ray Computed/*methods ; *Radiographic Image Interpretation, Computer-Assisted ; Phantoms, Imaging ; Kidney Diseases, Cystic/*radiography ; Iohexol/analogs & derivatives/diagnostic use ; Humans ; Contrast Media

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 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

OBJECTIVE: The aim of this study was to use fractal dimension (FD) analysis on multidetector CT (MDCT) images for quantifying the morphological changes of the pulmonary artery tree in patients with pulmonary hypertension (PH). MATERIALS AND METHODS: Fourteen patients with PH and 17 patients without PH as controls were studied. All of the patients underwent contrast-enhanced helical CT and transthoracic echocardiography. The pulmonary artery trees were generated using post-processing software, and the FD and projected image area of the pulmonary artery trees were determined with ImageJ software in a personal computer. The FD, the projected image area and the pulmonary artery pressure (PAP) were statistically evaluated in the two groups. RESULTS: The FD, the projected image area and the PAP of the patients with PH were higher than those values of the patients without PH (p < 0.05, t-test). There was a high correlation of FD with the PAP (r = 0.82, p < 0.05, partial correlation analysis). There was a moderate correlation of FD with the projected image area (r = 0.49, p < 0.05, partial correlation analysis). There was a correlation of the PAP with the projected image area (r = 0.65, p < 0.05, Pearson correlation analysis). CONCLUSION: The FD of the pulmonary arteries in the PH patients was significantly higher than that of the controls. There is a high correlation of FD with the PAP.
Adult ; Aged ; Case-Control Studies ; Contrast Media/diagnostic use ; Female ; *Fractals ; Humans ; Hypertension, Pulmonary/*radiography ; Iohexol/analogs & derivatives/diagnostic use ; Male ; Middle Aged ; Pulmonary Artery/*radiography ; Radiographic Image Interpretation, Computer-Assisted/*methods ; *Tomography, Spiral Computed

OBJECTIVE: To assess the technical feasibility and local efficacy of biplane fluoroscopy plus US-guided percutaneous radiofrequency ablation (RFA) for viable hepatocellular carcinoma (HCC) around retained iodized oil after transcatheter arterial chemoembolization (TACE). MATERIALS AND METHODS: Our prospective study was approved by our institutional review board and informed consent was obtained from all participating patients. For patients with viable HCC around retained iodized oil after TACE, biplane fluoroscopy plus US-guided RFA was performed. We evaluated the rate of technical success and major complications on a post-RFA CT examination and local tumor progression with a follow-up CT. RESULTS: Among 40 consecutive patients, 19 were excluded due to one of the following reasons: poorly visible HCC on fluoroscopy (n = 13), high risk location (n = 2), RFA performed under monoplane fluoroscopy and US guidance (n = 2), and poorly identifiable new HCCs on US (n = 2). The remaining 21 patients with 21 viable HCCs were included. The size of total tumors ranged from 1.4 to 5.0 cm (mean: 3.2 cm) in the longest diameter. Technical success was achieved for all 21 HCCs, and major complications were observed in none of the patients. During the follow-up period (mean, 20.3 months; range, 6.5-29.9 months), local tumor progression was found in two patients (2/21, 9.5%). Distant intrahepatic metastasis developed in 76.2% (16/21) of patients. CONCLUSION: When retained iodized oil around the tumor after TACE hampers the targeting of the viable tumor for RFA, biplane fluoroscopy plus US-guided RFA may be performed owing to its technical feasibility and effective treatment for viable HCCs.
Aged ; Aged, 80 and over ; Carcinoma, Hepatocellular/radiography/*surgery/therapy ; *Catheter Ablation ; *Chemoembolization, Therapeutic ; Complex Mixtures ; *Contrast Media ; Female ; *Fluoroscopy/methods ; Humans ; Iodized Oil/*administration & dosage ; Iohexol/analogs & derivatives/diagnostic use ; Liver Neoplasms/radiography/*surgery/therapy ; Male ; Middle Aged ; *Ultrasonography, Interventional

OBJECTIVE: This study was designed to determine the optimal mixture ratio of gadolinium and iodinated contrast agent for simultaneous direct MR arthrography and CT arthrography. MATERIALS AND METHODS: An in vitro study was performed utilizing mixtures of gadolinium at six different concentrations (0.625, 1.25, 2.5, 5.0, 10 and 20 mmol/L) and iodinated contrast agent at seven different concentrations (0, 12.5, 25, 37.5, 50, 75 and 92-99.9%). These mixtures were placed in tissue culture plates, and were then imaged with CT and MR (with T1-weighted sequences, proton-density sequences and T2-weighted sequences). CT numbers and signal intensities were measured. Pearson's correlation coefficients were used to assess the correlations between the gadolinium/iodinated contrast agent mixtures and the CT numbers/MR signal intensities. Scatter diagrams were plotted for all gadolinium/iodinated contrast agent combinations and two radiologists in consensus identified the mixtures that yielded the optimal CT numbers and MR signal intensities. RESULTS: The CT numbers showed significant correlation with iodinated contrast concentrations (r = 0.976, p < 0.001), whereas the signal intensities as measured on MR images showed a significant correlation with both gadolinium and iodinated contrast agent concentrations (r = -484 to -0.719, p < 0.001). A review of the CT and MR images, graphs, and scatter diagram of 42 combinations of the contrast agent showed that a concentration of 1.25 mmol/L gadolinium and 25% iodinated contrast agent was the best combination for simultaneous CT and MR imaging. CONCLUSION: A mixture of 1.25 mmol/L gadolinium and 25% iodinated contrast agent was found to be optimal for simultaneous direct MR arthrography and CT arthrography.
*Arthrography ; Contrast Media/*administration & dosage ; Gadolinium/administration & dosage/*diagnostic use ; Iohexol/administration & dosage/*analogs & derivatives/diagnostic use ; *Magnetic Resonance Imaging ; Meglumine/administration & dosage/*diagnostic use ; Organometallic Compounds/administration & dosage/*diagnostic use ; Phantoms, Imaging ; *Tomography, X-Ray Computed

This study was undertaken to compare renal damage, as determined by serum creatinine and degree of apoptosis, caused by iodinated contrast or gadolinium in an acute renal failure (ARF) rat model. Rats were divided into three groups; controls (n=3), a CT contrast medium group (n=9), and an MR contrast medium group (n=9). The CT and MR groups were further subdivided into three groups, namely, low, standard, and high dose subgroups. Renal function was evaluated by determining serum creatinine levels; before ARF, and 48 hr after ARF and contrast administration. Apoptosis was assayed by terminal deoxynucleotidyl transferasemediated dUTP nick-end labeling (TUNEL). No significant creatinine level differences were observed between the CT and MR groups (p=0.116). Degrees of apoptosis in the renal cortex and medulla were more severe in the CT contrast medium group than in the control or MR contrast medium group (p<0.05). The study shows that CT contrast medium did not aggravate renal function more so than MR contrast medium in this ARF rat model. However, apoptosis examination in the renal cortex and medulla indicated that CT contrast medium induced more severe apoptosis than MR contrast medium (p<0.05). We conclude that CT contrast medium can be used for renal imaging studies when subjects are well hydrated and preventive medication is administered.
Animals ; Apoptosis/*drug effects ; Contrast Media/adverse effects ; Creatine/*blood ; Female ; Gadolinium DTPA/*adverse effects ; Iohexol/adverse effects/*analogs and derivatives ; Kidney/*drug effects/*pathology ; Kidney Failure, Acute/*blood/pathology/radiography ; Male ; Rats ; Rats, Sprague-Dawley ; Research Support, Non-U.S. Gov't

We describe the enhancement patterns of myoepithelioma in two patients with a soft palate mass. In the first case, helical CT revealed a faintly enhancing mass. Histologically, the tumor was composed of plasmacytoid cells in a background of rich myxoid stroma. Immunostaining for CD34 showed scanty blood vessels. In the second case, helical CT revealed an intensely enhancing mass. Histologically, the mass was a cellular tumor with fibrous stroma. Immunostaining for CD34 also showed frequent blood vessels.
Aged ; Contrast Media/administration & dosage ; Diagnosis, Differential ; Female ; Humans ; Iohexol/analogs & derivatives/diagnostic use ; Male ; Middle Aged ; Myoepithelioma/*diagnosis/surgery ; Palatal Neoplasms/*diagnosis/surgery ; Palate, Soft/*radiography/surgery ; Radiographic Image Enhancement/methods ; Rare Diseases ; Tomography, Spiral Computed/*methods