Assessment of Contrast-enhanced 3D Ultrafast Pulmonary MR Angiography Using Test Injection: Comparison betweenSingle Dose and Double Dose

PURPOSE: Contrast-enhanced 3-D ultrafast MR angiography is a widely accepted MR imaging technique for theevaluation of the carotid artery, aorta, renal artery, mesenteric artery and portal venous system. To esti-mateitsclinical usefulness, single -and double- dose contrast-enhanced 3-D ultrafast pulmonary MR angiography wasassessed after a timing examination was performed. MATERIALS AND METHODS: Twenty volunteers underwentgadolinium-enhanced ultrafast pulmonary MR angiog-raphy( 3-D FISP, TR[msec]/TE[msec]=5.0/2.0, with 25 degrees flipangle). In ten volunteers(single-dose injection group) pulmonary MR angiography was performed after theadminstration of 0.1 mmol/kg(single dose injec-tion group), while the other ten(double-dose injection group) eachreceived, prior to angiography, 0.2 m m o l / kg. In all cases, a timing examination was performed during axialturbo-FLASH imaging(TR/TE/TI=8.5/4.0/100, 1 0 degree flip angle) after injection of the same dose as that used forsubsequent contrast-enhanced pulmonary MR angiography. In both groups, overall image quality, pulmonary arteryvisibility and contrast-to-noise ratio of the pulmonary artery were assessed on the basis of images obtained.RESULTS: With regard to overall image quality, there was no significant statistical difference between the twogroups (P>0.05), and in both, depiction of the central and lobar pulmonary artery was excellent. As regardsdepiction of the segmental artery, the average grading of the single dose injection group was 2.83 +/- 0.32, that ofthe double dose injection group was 2.85 +/-0.3, with no statistical significance(P>0.05). With respect tocon-trast-to-noise ratio of the central, lobar, and segmental arteries, the best results were obtained by thedouble dose injection group(P<0.05). CONCLUSION: Although the contrast-to-noise ratio in the double-dose injectiongroup was better than that in the single-dose group, differences in overall image quality and pulmoanry arterydepiction were not statistically significant. Thus, single-dose, contrast-enhanced 3-D ultrafast pulmonary MRangiography can provide useful images in clinical trials.

Borrmann Type IV Adenocarcinoma versus Gastric Lymphoma: Spiral CT Evaluation

PURPOSE: To distinguish the spiral CT findings of Borrmann type IV adenocarcinoma from those of gastric lymphoma with diffuse gastric wall thickening. MATERIALS AND METHODS: We retrospectively reviewed the spiral CT scans of 30 patients with Borrmann type IV adenocarcinoma and nine with gastric lymphoma with diffuse gastric wall thickening. In all patients the respective condition was pathologically confirmed by gastrectomy. CT scanning was performed after peroral administration of 500-700ml of water. A total of 120-140ml bolus of nonionic contrast material was administered intravenously at a flow rate of 3ml/sec and two-phase images were obtained at 35-45 sec(early phase) and 180 sec(delayed phase) after the start of bolus injection. Spiral CT was performed with 10mm collimation, 10mm/sec table feed and 10mm reconstruction. We evaluated the degree and homogeneity of enhancement of thickened entire gastric wall, and the enhancement pattern of gastric inner layer, as seen on earlyphase CT scans. On early and delayed views, the thickness of gastric wall and the presence of perigastric fat infiltration were determined. The enhancement patterns of gastric inner layer were classified as either continuous or discontinuous thick enhancement, thin enhancement, or nonenhancement. RESULTS: The thickness of gastric wall was 1.2-3.5cm(mean 2.2cm) in cases of adenocarcinoma and 1.2-7.6c m (mean 4cm) in lymphoma. Perigastric fat infiltration was seen in 24 patients with adenocarcinoma(80 %) and four with lymphoma(44%). In those with adenocarcinoma, the degree of enhancement of entire gastric wall was hyperdense in fifteen patients(50%) and isointense in eleven (37 %). Seven patients with lymphoma(78 % ) showed hypodensity. In those with adenocarcinoma, continuous thick enhancement of gastric inner layer was seen in 18 patients(60 %) and discontinuous thick enhancement in nine(30%). In lymphoma cases, no thick enhancement was observed. Thin enhancement of gastric inner layer was demonstrated in three patients with adenocarcinoma( 10 %) and two with lymphoma(22 %). In seven patients with lymphoma(78 %), there was no enhancement. CONCLUSION: The following early-phase findings are highly suggestive of gastric lymphoma: a gastric wall thickness of more than 3 cm; no or minimal perigastric fat infiltration, hypodense enhancement of thickened entire gastric wall; and no or thin enhancement of gastric inner layer.

Quantitative Evaluation in Enhancement of Pancreas and Adjacent Vessels during Spiral CT

PURPOSE: To determine by quantitative evaluation of pancreatic and adjacent vascular enhancement during spiral CT, the ideal scan delay for examination of the pancreas. MATERIALS AND METHODS: Dual (n=90) and triple (n=90) phase spiral CT scans of patients whose pancreas showed no pathologic condition were retrospectively evaluated. Dual-phase scans were performed at 43 seconds (early), and 5-6 minutes (delayed) after the injection of 120ml of contrast material at an injection rate of 3ml/sec ; triple-phase scans were performed at 25 seconds (arterial), 60-65 seconds (portal) and 5-6 minutes (delayed) after the injection of 120-140ml of contrast material at an injection rate of 2-4ml/sec, and ten patients also underwent precontrast scanning. CT attenuation values (HU) were measured in the head, body and tail of the pancreas, aorta, and main portal vein during each phase of all scans. Triple-phase protocol was used to measure the effect of different total volumes and injection rates on enhancement of the pancreas and adjacent vessels. RESULTS: There was no significant difference in the degree of enhancement of the pancreas head, body and tail during each phase (p>0.05). The pancreas was maximally enhanced on 43 second delayed scan (132+/-20 HU)(p0.05). The main portal vein showed maximum enhancement on 43-second delayed scan (207+/-44 HU)(p<0.05). Different total volume of contrast material did not change the enhancement of the pancreas and adjacent vessels. At an injection rate of 2ml/sec, peak enhancement of the pancreas, aorta and portal vein was obtained on 60-65 second delayed scan, and at 4ml/sec, peak enhancement was obtained on 25 second delayed scan(p<0.05). CONCLUSION: Observing the usual protocols for abdominal spiral CT scanning, the pancreas was most effectively evaluated using a 43-second delayed scan. An increased injection rate resulted in earlier enhancement of the pancreas, aorta and portal vein.

Portal Venous Anatomy in Right Lobe of the Liver: CT Evaluation

PURPOSE: To evaluate the portal venous anatomy in the right lobe of the liver, focusing particularly on the location and size of the anterior and posterior segmental branches of the portal vein and the relationship of the right subdiaphragmatic peripheral portal vein to the right hepatic vein. MATERIALS AND METHODS: From June 1995 to December 1995, 100 spiral CT scan which showed no abnormal findings in the hepatic area were retrospectively analysed. Portal dominant phase images were obtained after the administration of contrast media, with a delay of 60-65 seconds (100 - 120ml, 2-3ml/sec injection rate), slice thickness 10 mm and table speed 10mm/sec. On spiral CT scans, we assessed the location and size of the right portal vein and its branches and also observed the relationship of this vein to the right hepatic vein. RESULTS: In all patients, the right portal trunk divided into anterior and posterior branches. The anterior segmental portal vein was located cephalad to the posterior segment in 81 cases (81%), at the same level in 17 (17%), and caudad in two (2%). Its diameter was greater (>2mm)than that of its posterior segment in 33 cases (33%), smaller in three (3%), and similar in 64 (64%). In 95 cases, the right anterior segmetal portal vein which was directed posteriorly, supplied the subdiaphragmatic portion of segment 7. CONCLUSION: In 81% of cases, the position of the anterior segmental portal vein cephalad, and in 64%of cases it was similar in size to the posterior portal vein. In almost all cases, the subdiaphragmatic portion of segment 7 was supplied by the portal vein from segment 8. Therefore, the right hepatic vein is not in all cases an adequate landmark for dividing Couinaud segments 7 and 8 in the subdiaphragmatic portion.

Portal Venous Anatomy in Right Lobe of the Liver: CT Evaluation

PURPOSE: To evaluate the portal venous anatomy in the right lobe of the liver, focusing particularly on the location and size of the anterior and posterior segmental branches of the portal vein and the relationship of the right subdiaphragmatic peripheral portal vein to the right hepatic vein. MATERIALS AND METHODS: From June 1995 to December 1995, 100 spiral CT scan which showed no abnormal findings in the hepatic area were retrospectively analysed. Portal dominant phase images were obtained after the administration of contrast media, with a delay of 60-65 seconds (100 - 120ml, 2-3ml/sec injection rate), slice thickness 10 mm and table speed 10mm/sec. On spiral CT scans, we assessed the location and size of the right portal vein and its branches and also observed the relationship of this vein to the right hepatic vein. RESULTS: In all patients, the right portal trunk divided into anterior and posterior branches. The anterior segmental portal vein was located cephalad to the posterior segment in 81 cases (81%), at the same level in 17 (17%), and caudad in two (2%). Its diameter was greater (>2mm)than that of its posterior segment in 33 cases (33%), smaller in three (3%), and similar in 64 (64%). In 95 cases, the right anterior segmetal portal vein which was directed posteriorly, supplied the subdiaphragmatic portion of segment 7. CONCLUSION: In 81% of cases, the position of the anterior segmental portal vein cephalad, and in 64%of cases it was similar in size to the posterior portal vein. In almost all cases, the subdiaphragmatic portion of segment 7 was supplied by the portal vein from segment 8. Therefore, the right hepatic vein is not in all cases an adequate landmark for dividing Couinaud segments 7 and 8 in the subdiaphragmatic portion.

Mammographic Findings of Infiltrating Ductal Carcinoma: Correlation with Histologic Grading and Age

PURPOSE: To investigate the correlation between mammographic findings of infiltrating ductal carcinoma (IDC), patient age and pathologic grading. MATERIALS AND METHODS: The study included 103 cases of infiltrating ductal carcinoma in 102 women who during the preceding three years had undergone mammography and surgery. The mammograms were retrospectively reviewed by two radiologists. The mean age of the patients was 45.2 (range 26-74) years and the age distribution was seven in the 3rd decade, 37 in the 4th, 29 in the 5th, 24 in the 6th, and six in the 7th or above. Thirty-three lesions were histologic. Grade I, 59 were Grade II and 11 were Grade III. RESULTS: Ten (9.7%) of 103 cases, all of whom were younger than 50, were missed during mammographic diagnosis. On mammograms, primary findings of breast malignancy were found in 54 (74%) of 73 patients younger than 50 and 27 (90%) of 30 patients older than 51. Mass with or without microcalcification was found in 45 patients (62%) younger than 50 and in 26 (87%) older than 51. Nine (12%) and 3 (10%) in each age group showed secondary findings. There was no correlation between age distribution and histologic grading. Seventy-three percent of Grade I lesions and 78% of those of Grade III showed primary findings. Five lesions in each of Grade I and II were missed at mammographic interpretation, but this was not statistically significant (p=0.250). In all 11 Grade III cases, breast cancer were manifested as primary findings but this was not statistically significant (p=0.203). CONCLUSION: The majority of IDC were detected by mammography, but 9.7% of IDC patients, all younger than 50, were misdiagnosed. Most IDC was manifested as primary findings, particularly in patients aged over 51. There were no differences in pathlogic grading according to age distribution. All histologic Grade III lesions were detected by mammography.

Effectiveness of Percutaneous Catheter Drainage for Tuberculous Iliopsoas Abscess associated with Tuberculous Spondylitis

PURPOSE: To evaluate the efficacy of percutaneous catheter drainage of tuberculous abscess associated with tuberculous spondylitis. MATERIALS AND METHODS: In twelve patients (male:female = 1:2; mean age, 37.3 years) tuberculous abscess was diagnosed, and was treated by percutaneous abscess drainage (PAD). All patients had either a psoas or iliopsoas abscess and in two, a paravertebral abscess was also present. Four had bilateral lesions, one, a unilateral lesion, and one, paravertebral abscesses and bilateral psoas. The size of abscesses ranged from4x5x12cm to 6x9x30cm; four were septated and all were lobulated. Using an 8.5-14F catheter, 17 of 18 abscesses were percutaneously drained; Ultrasound guidance was used in 12 cases, and CT guidance in five. RESULTS: The volume of drainage mater ranged from 150 to 1200 cc(mean, 600cc), and the duration of catheter insertion was 6-48 (mean, 17.4) days. In no patient did significant complications arise during or after drainage, and in all cases, follow-up studies using ultrasound, CT or MRI were performed. The duration of follow-up ranged from 3 to 35 (mean,15.4) months; during this time, no recurrence was noted. CONCLUSION: Chemotherapy alone is sufficient for treating a small tuberculous psoas or iliopsoas abscess, but for a large abscess, adjuvant drainage is necessary.