The Usefulness of CO2 Indirect Portography in Transjugular Intrahepatic Portosystemic Shunt(TIPS)

PURPOSE: To determine the usefulness of carbon dioxide(CO2) indirect portography during TIPS procedure. MATERIALS AND METHODS: We evalvated eight patients who had undergone TIPS due to variceal hemorrhage or ascites caused by portal hypertension. All patients but one with complete situs inversus underwent wedged right hepatic venography for visualization of the portal vein using CO2. For CO2 indirect portal venography, 50cc of CO2 was injected by hand without prior injection of a small amount of CO2. In three patients a 5-F angiographic catheter was wedged into the right hepatic vein, and in the other five a 9-F sheath from a Ring 's transjugular access set was adjunctively wedged into the right hepatic vein over the 5-F catheter. The time required for portal vein puncture was defined as the time between the indirect portal venography procedure and the first procedure after successful portal vein puncture. RESULTS: All patients successfully underwent TIPS without any immediate complication. The portal vein was visualized by CO2 in 7 of 8 patients (87.5 %). Two of three patients who underwent indirect portography with only a 5-F catheter wedging demonstrated opacification of the right portal vein; in the remaining patient the portal venous system was not visualized. Of the five patients who underwent indirect portography with an adjunctive 9-F sheath wedged in the right hepatic vein, four showed opacification from the peripheral to the main portal vein, and in the other, the only right peripheral portal vein was opacified. The mean time for portal vein puncture was 20.5 minutes. CONCLUSION: For visualization of the portal venous system during TIPS procedure, the use of CO2 indirect portography is feasible.

MRI Findings of Hydroxyapatite Orbital Implants

PURPOSE: To assess MR findings of hydroxyapatite orbital implants and their usefulness for the evaluation of fibrovascular ingrowth. MATERIALS AND METHODS: MR images of 32 hydroxyapatite orbital implants were obtained six months after implantation surgery. We retrospectively analysed MR images for signal intensity and contrast enhancement in both central and peripheral zones of the implants. The degree of contrast enhancement in an implant was compared with that of the temporalis muscle on contrast enhanced fat suppressed T1 weighted images. RESULTS: On T1-weighted images, implants showed a higher signal intensity than that of the vitreous body in the opposite globe. All implants showed peripheral contrast enhancement, densely enhanced in 30 cases and faintly in two. Three implants showed dense central contrast enhancement, and in the remainder, enhancement was similar to that of gray matter. On T2 weighted images, bright signal intensity was noted in 29 implants, focally in 19 and diffusely in ten. In most cases, areas of peripheral iso- to low signal intensity on T2-weighted images corresponded well with the contrast-enhanced area on T1 weighted images. CONCLUSION: At six months ofter surgery, Gd-enhanced MR imaging was useful for the evaluation of fibrovascular ingrowth in hydroxyapatite orbital implants.

Imaging Diagnosis in Various Renal Sinus Lesion

The renal sinus extends from the perinephric space into the deep recess situated on the medial border of the kidney. Contained within the space are the pelvocalyceal system, fat and lymph nodes. Arteries, veins, lymphatic channels and nerves of the autonomic nervous system traverse the sinus, and various pathological conditions may occur in this area. These various sinusal lesions may present a similar imaging appearance, and diagnostic errors may frequently occur, especially if diagnosis is attempted without first clearly understanding the several possibilities. This pictorial essay demonstrates various renal sinus lesions and emphasizes the proper combination of multimodal imaging. For evaluation of the extent of the lesious, CT is the preferred imaging modality, since this best depicts the anatomy of the renal sinus. Using a proper combination of multimodal imaging, specific diagnosis was in most cases possible.

Various Complications of Abdominal Aortic Aneurysm: CT Findings

PURPOSE: To evaluate on abdominal CT the type and incidence of various complications of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: Twenty six suspected cases of AAA were confirmed by operation(n=21) and by CT(n=5). The etiology, size, shape and incidence of various complications of AAA were then retrospectively evaluated. In addition, post-operative complications were also evaluated in five cases. RESULTS: The etiology ofthe aneurysm was atherosclerotic in 18 cases and mycotic in three ; it showed the presence of Behcet disease in three cases, of tuberculosis in one, and of Marfan syndrome in one. Among the 18 fusiform AAA, the mean maximum diameter of ruptured AAA(7.5+/-3.3cm, n=3) was significantly larger than that of unruptured AAA(4.9+/-1.6cm, n=15)(p<0.05). The saccular type was much more likely to rupture than the fusiform type(p<0.00001). Out of the eight saccular AAA, seven ruptured ; their mean maximum diameter was 3.9+/-1.3cm This was significantly smaller than that of ruptured fusiform aneurysm(p<0.05). The most common complication was rupture, and occurred ten of 26 cases(38%). Others included hydronephrosis in three cases, bowel infarction in one, and perianeurysmal retroperitoneal fibrosis in one case. Various post-operative complications developed in five patients ; these comprised periprosthetic pseudoaneurysm with hematoma (two cases), bowel ischemia (one), focal renal infarction(one), and secondary aorticoduodenal fistula (one). CONCLUSION: The most common complication of AAA was rupture, the rate of which was much higher in the saccular type with smaller size than the fusiform type. Other various and uncommon complications were observed. CT was helpful in detecting complications arising from AAA and in planning its treatment.

Various Complications of Abdominal Aortic Aneurysm: CT Findings

PURPOSE: To evaluate on abdominal CT the type and incidence of various complications of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: Twenty six suspected cases of AAA were confirmed by operation(n=21) and by CT(n=5). The etiology, size, shape and incidence of various complications of AAA were then retrospectively evaluated. In addition, post-operative complications were also evaluated in five cases. RESULTS: The etiology ofthe aneurysm was atherosclerotic in 18 cases and mycotic in three ; it showed the presence of Behcet disease in three cases, of tuberculosis in one, and of Marfan syndrome in one. Among the 18 fusiform AAA, the mean maximum diameter of ruptured AAA(7.5+/-3.3cm, n=3) was significantly larger than that of unruptured AAA(4.9+/-1.6cm, n=15)(p<0.05). The saccular type was much more likely to rupture than the fusiform type(p<0.00001). Out of the eight saccular AAA, seven ruptured ; their mean maximum diameter was 3.9+/-1.3cm This was significantly smaller than that of ruptured fusiform aneurysm(p<0.05). The most common complication was rupture, and occurred ten of 26 cases(38%). Others included hydronephrosis in three cases, bowel infarction in one, and perianeurysmal retroperitoneal fibrosis in one case. Various post-operative complications developed in five patients ; these comprised periprosthetic pseudoaneurysm with hematoma (two cases), bowel ischemia (one), focal renal infarction(one), and secondary aorticoduodenal fistula (one). CONCLUSION: The most common complication of AAA was rupture, the rate of which was much higher in the saccular type with smaller size than the fusiform type. Other various and uncommon complications were observed. CT was helpful in detecting complications arising from AAA and in planning its treatment.