Positive and negative oral contrast agents for combined abdominal and pelvic helical CT: first iodinated agent and second water.

Combined abdominal and pelvic helical computed tomography (CT) with intravenous contrast media was performed on 19 patients with 400 mL of diluted iodine solution 60 minutes before and 400 mL of water just before CT. The distal small bowel was opacified by the positive contrast agent, and the stomach by the negative contrast agent in all patients. The gastric contents were homogenous, and the density was a mean +/- standard deviation 2.5+/-7.3 HU. The difference between the densities of the gastric contents and of the gastric wall (mean +/- s.d. 80.8+/-20.9 HU) was statistically significant (p<.05). There were no pseudotumors. Thus our protocol, first diluted iodine solution and second water, can be used as a method for the oral administration of contrast agents for combined abdominal and pelvic helical CT with intravenous contrast media.

[Radiation dose measurement of the patient in interventional radiology using a transmission ionization chamber].

We propose a method to estimate patient radiation dose in radiologically guided interventional procedures using a transmission ionization chamber. A typical transarterial embolization (TAE) procedure for hepatocellular carcinoma was simulated, including 30 minutes of fluoroscopy and five series of DSA, each with appropriate collimation. The dose-area product was divided by the area and compared with values from a standard dosimeter placed in the center of the radiation entrance, to obtain a conversion factor. In this way, the entrance skin dose can be estimated immediately after the procedure by simply multiplying the value by the conversion factor, if the procedure roughly conforms to the simulated model. The average entrance skin dose of 33 patients who recently underwent TAE for HCC was found to be 0.66 (0.19-1.75) Gy. This technique can be applied to other areas of IVR and may help to reduce patient exposure to radiation.

Pseudomyxoma retroperitonei.

We report a rare case of pseudomyxoma retroperitonei in a 58-year-old woman with a past history of severe appendicitis. The imaging showed a multicystic mass similar to pseudomyxoma peritonei, but the tumor was located in the retroperitoneal space.

[A clinical and portal hemodynamic analysis for obliteration of gastric-renal shunt communicated with gastric fundic varices].

To clear the efficacy of treatment for large porto-systemic shunts, changes of liver function and portal hemodynamics after obliteration of gastric-renal shunt (GRS) or gastric-inferior phrenic vein shunt (GIS) communicated with gastric fundic varies in 24 patients treated with balloon-occluded retrograde transvenous obliteration (B-RTO) were studied. 1) The wedged hepatic venous pressure and the hepatic venous pressure gradient were statistically not significant changed after obliteration of GRS or GIS. 2) Serum albumin value was significantly increased (p < 0.005) and ICGR15 was significantly improved (p < 0.005) at one year after treatment in patients that, not only whose GRS or GIS were larger than 10mm in diameter, but also whose superior mesenteric arterial venography before treatment showed hepatofugal flow. 3) At a mean follow-up abdominal angiography of 23.3 months in 20 cases, GRS or GIS was yet obliterated respectively. And more, superior mesenteric arterial venography revealed hepatopetal flow alone in 43% of patients that, whose superior mesenteric arterial venography before treatment showed hepatofugal flow. 4) During a mean follow-up of 32.5 months, gastric fundic varies were not recurrent in all patients, but the other hand, cumulative red color sign positive esophageal varies apparent rates were high (16.7% at before treatment, 38.4% at 2-years, 54.4% at 4-years). According to their hemodynamic characteristics, cumulative red color sign positive esophageal varies apparent rates in patients with another collaterals besides GRS or GIS before treatment (26.7% at before treatment, 61.1% at 2-years, 74.1% at 4-years) were significantly higher (p < 0.05) than those in patients without another collateral except GRS or GIS (0% at 2-years, 16.7% at 4-years). We conclude that, 1) Increment of portal flom and improvement of liver function can be expected by obliteration of GRS or GIS in patients that, whose superior mesenteric venous blood flow into large GRS or GIS. 2) After obliteration of GRS or GIS, the incidence of aggravation of esophageal varies in patients with another collaterals besides GRS or GIS before treatment is high, while that in cases without another collateral is low.

[High-resolution CT findings in cytomegalovirus pneumonitis after bone marrow transplantation].

In order to explore the high-resolution CT (HRCT) findings of cytomegalovirus (CMV) pneumonitis after bone marrow transplantation, we retrospectively reviewed the HRCT findings in nine patients with CMV pneumonitis cytologically proven by bronchoalveolar lavege. In 67% of cases, HRCT showed ground-glass attenuation. Consolidation and bronchial wall thickening were demonstrated in 33%, pleural effusion in 22%, and micro centrilobular nodules, bronchiectasis, and reticulation in 11%, respectively. Lymphadenopathy and masses were not seen. The areas of ground-glass attenuation were distributed bilaterally in all cases, diffusely in 67%, centrilobularly in 50%, and panlobularly in 50%. Subpleural lung regions were spared in 83%. The areas of consolidation were bilateral in 67%, nonsegmental in 67%, and involved the lower lobe in all cases. A total of 25 follow-up HRCT were performed in six patients. Small centrilobular ground-glass opacities disappeared after treatment in one patient. Micro centrilobular nodules vanished after treatment in one patient. Small centrilobular ground-glass opacities developed into consolidation and resolved after treatment in one patient. In one patient, diffuse ground-glass opacities progressed to consolidation, and the patient died due to respiratory failure. No abnormal findings were observed in two patients. It may be considered that in the early phase of CMV pneumonitis HRCT shows small or micro centrilobular ground-glass opacities and nodules and that in the advanced phase these lesions progress to dense alveolar opacities as CMV infection advances, although a variety of HRCT appearances is observed in the course of CMV pneumonitis.

Balloon-occluded retrograde transvenous obliteration for gastric varices: a feasibility study.

PURPOSE: To evaluate the clinical feasibility of balloon-occluded retrograde transvenous obliteration (BORTO) for gastric varices. METHODS: BORTO was performed in 14 patients with gastric varices due to liver cirrhosis. The gastric varices were confirmed by endoscopy, and their feeding and draining veins were identified by contrast-enhanced computed tomography (CT) and angiography. A 6 Fr Simmons-shaped balloon catheter was inserted into the gastrorenal shunt. The balloon was inflated, and 5% ethanolamine oleate iopamidol was infused slowly through the catheter. Patients were followed up with endoscopy and enhanced CT at 1 week, 1, 3, and 6 months after the procedure and every 6 months thereafter. RESULTS: The gastric varices completely disappeared in 12 of 14 patients and was partially resolved in the remaining 2 patients. Neither a recurrence nor an aggravation of gastric varices were found. No major complications were experienced. CONCLUSION: BORTO is a safe and effective treatment for gastric varices.

"Oblique path"--the optimal needle path for computed tomography-guided biopsy of small subpleural lesions.

PURPOSE: To determine the optimal needle path for computed tomography (CT)-guided biopsy of small lesions just beneath the pleura. METHODS: A biopsy of 61 subpleural lesions measuring less than 2.5 cm was done prospectively with regard to the approach and the results. One of two needle paths was randomly chosen: a nearly right angle path (n = 30) or an "oblique path" in which the needle was sharply inclined within the slice, using a course nearly parallel to the pleura (n = 32). One lesion was sampled twice. The procedures were considered successful when diagnostic samples were obtained. RESULTS: The success rate of the oblique path was 81.2% and that of the near 90 degrees path was 43.3% (p < 0.05). CONCLUSION: For percutaneous biopsy of small subpleural lesions under CT guidance, the oblique path is better than the perpendicular path.

Pseudodynamic imaging of the temporomandibular joint: SE versus GE sequences.

Pseudodynamic MR imaging of the temporomandibular joints (TMJs) has been used for the evaluation of the functional aspects of the TMJs. To evaluate the value of T1-weighted spin-echo (SE) and gradient-echo (GE) techniques, both techniques were performed in 9 asymptomatic (mean 25.7 years, 22-23 years), and 25 symptomatic (mean 44.9 years, 20-71 years) subjects with signs and symptoms of internal derangement or osteoarthrosis of the TMJs. The imaging time for the SE (180 ms/15 ms/110 degrees; repetition time/echo time/flip angle) and GE (fast low angle shot; FLASH, 90 ms/12 ms/40 degrees) sequences was 27 and 28 s, respectively. In asymptomatic and symptomatic subjects, the confidence of the identification of the meniscal position was better on SE than GE images (3.6 +/- 0.6 vs. 2.9 +/- 0.9, p < 0.01, 3.2 +/- 0.8 vs. 2.8 +/- 0.8, p < 0.05), respectively and the sizes of the menisci were bigger on SE than GE images. The delineation of the condylar cortex was better on GE than SE images. For pseudodynamic imaging display of the TMJs, the SE images might be better than GE images to provide the stable recognition of the menisci.

Clinical evaluation of pulmonary 3D time-of-flight MRA with breath holding using contrast media.

OBJECTIVE: Our goal was to evaluate the clinical utility of pulmonary 3D TOF MRA using a contrast medium and breath holding. MATERIALS AND METHODS: To determine an optimal imaging time in a pilot study, 30 sequential axial images were obtained for each of 18 patients by using a turbo fast low angle shot sequence immediately after a bolus injection of 5 ml Gd-DTPA. MRA consisted of five sequential MR scans performed using a 3D fast imaging with steady-state precession sequence on 13 patients. The imaging start time after a bolus injection of 10 ml Gd-DTPA was determined from the results of the pilot study. We hoped that the acquisition of the center of k-space of the first MRA was matched to the period of maximum effect of the first pass bolus for the pulmonary arteries. RESULTS: In a pilot study on average, pulmonary artery signal intensities were relatively high from 10.4 to 20.7 s after the contrast medium injection. The MR angiograms obtained at the optimal time were superior to those that followed. All pulmonary trunks and the right and left main pulmonary arteries were accurately recognized. MRA had a sensitivity of 80.0%, a specificity of 95.0%, and an accuracy of 94.5% for the detection of segmental artery stenosis or occlusion. Abnormal vessels were visualized in both patients with pulmonary sequestration. CONCLUSION: Pulmonary 3D TOF MRA using breath holding and a contrast medium is useful in demonstrating proximal pulmonary vasculature and pulmonary sequestration.