Kiyoshi Nishimine

Transcatheter hepatic segmental arterial embolization using lipiodol mixed with an anticancer drug and gelfoam particles for hepatocellular carcinoma

Transcatheter hepatic segmental arterial chemoembolization using Lipiodol mixed with an anticancer drug followed by the injection of Gelfoam particles, introduced into the tumor-bearing hepatic segment as the target area (segemental Lipiodol-TAE), was carried out in 54 patients with hepatocellular carcinoma (HCC), 7 of whom were later resected. In 5 of the resected 7 cases, complete necrosis was histologically verified. No death due to HCC was encountered in 47 nonoperated cases, and better therapeutic results were obtained with segmental Lipiodol-TAE. It was concluded that this technique does not adversely affect normal tissues, and it does reinforece the effect of TAE.

Pharmacologic Treatment of Intimal Hyperplasia After Metallic Stent Placement in the Peripheral Arteries: An Experimental Study

RATIONALE AND OBJECTIVES.To evaluate the efficacy of oral administration of cilostazol, an antithrombotic agent, for the prevention of thrombotic occlusion and intimal hyperplasia after steanting. METHODS.Single-bodied Z-stents were placed in the iliac arteries of 23 dogs. Before stenting, an embolizing coil was introduced into the right femoral artery to reduce blood flow in the right iliac artery. Eleven dogs were given cilostazol orally, and the other 12 were unmedicated as a control group. The dogs were killed at 4,13, and 24 weeks. RESULTS.Intraluminal narrowing due to thrombus was observed in 25% of dogs in the control group but in none of the dogs in the cilostazol group. The thickness of the neointima was significantly thinner in the cilostazol group than in the control group at 24 weeks on the noncoiled side (P<0.05), and at 4 and 24 weeks on the coiled side (P<0.01). CONCLUSIONS.These results suggest that oral administration of cilostazol is an effective method of preventing thrombotic occlusion and intimal hyperplasia after stenting.

Acute aortic dissection with intramural hematoma : possibility of transition to classic dissection or aneurysm

Acute aortic dissection with intramural hematoma has been believed to have a good prognosis, but we have encountered the transition of this entity to a classic dissection or aneurysm. We report the serial computed tomography (CT) features in 27 cases of acute aortic dissection with intramural hematoma. Eleven patients (40.7%) developed a classic dissection or aneurysm during follow-up. Four patients (14.8%) showed transition to a classic dissection without resolution of the intramural hematoma; each had a dilated ascending aorta measuring >5 cm in diameter on the initial CT. One case (3.7%) developed an enlarging aneurysm without resolution of the intramural hematoma. In 19 cases (70.4%), the hematoma resolved; among these 19, the aortic diameter was significantly larger (p < 0.01) than those in a normal control group. Two of these 19 later developed an aneurysm, and four developed a classic dissection. This entity often (40.7%; 11 of 27) required surgical intervention or periodic follow-up CT examinations, particularly with a dilated ascending aorta of >5 cm in diameter.

Segmental transarterial chemoembolization with lipiodol mixed with anticancer drugs for nonresectable hepatocellular carcinoma: follow-up CT and therapeutic results

We developed segmental Lp-TAE, which is transcatheter hepatic sub-subsegmental, subsegmental, or segmental chemoembolization using Lipiodol introduced into the tumor-bearing hepatic sub-subsegment, subsegment, or segment as the target area. A total of 98 patients with nonresectable hepatocellular carcinoma (HCC) undergoing segmental Lp-TAE (Seg-Lp-TAE) were studied, and the relationship between the CT pattern observed after Seg-Lp-TAE (Seg-Lp-CT) and the therapeutic results obtained in those patients was evaluated. Seg-Lp-CT was classified into four types (type I, homogeneous; type II, defective; type III, inhomogeneous; and type IV, only slight accumulation, if any) according to the Lipiodol accumulation pattern observed after Seg-Lp-TAE. The cumulative nonrecurrence rates of type I were higher than those of types II–IV. The cumulative survival rates of type Ia, in which Lp accumulation is also seen around the main tumor, were the highest (93.8% at 1 year, 85.9% at 2 years, 85.9% at 3 years, and 57.3% at 4 years). The cumulative survival rates achieved with Seg-Lp-TAE were 89.2% at 1 year, 69.4% at 2 years, 58.9% at 3 years, 44.0% at 4 years, and 30.2% at 5 years, which were higher than those achieved with conventional Lp-TAE. Seg-Lp-TAE is very useful in the treatment of HCC limited to one sub-subsegment, subsegment, or segment, and it is important to choose subsubsegmental, subsegmental, subsegmental, or segmental Lp-TAE on the basis of the size and site of the tumor as well as the type and the number of feeding arteries.

Long-term outcomes for systematic primary stent placement in complex iliac artery occlusive disease classified according to Trans-Atlantic Inter-Society Consensus (TASC)-II

PURPOSE To compare long-term outcomes of systematic primary stent placement between Trans-Atlantic Inter-Society Consensus (TASC)-II C/D disease and TASC-II A/B disease. METHODS Between 1997 and 2009, endovascular treatments with primary stent placement were performed for 533 lesions in 413 consecutive patients with iliac artery occlusive disease. Median follow-up term was 72 months (range, 1-144 months). Lesion severity in this retrospective study was classified according to TASC-II as type A in 134 patients (32%), type B in 154 patients (37%), type C in 64 patients (16%), and type D in 61 patients (15%). Technical success rates, procedure time, complication rates, and cumulative primary patency rates were compared between the complex lesion group (TASC-II type C/D) and the simple lesion group (TASC-II type A/B). Risk factors for in-stent restenosis were also analyzed. RESULTS Technical success rates in TASC-II C/D and A/B were both 99%. Procedure times for TASC-II type A, B, C, and D lesions were 98 ± 40, 124 ± 50, 152 ± 55, and 183 ± 68 minutes, respectively. Procedure time was significantly longer in TASC-II C/D (167 ± 63 minutes) than in TASC-II A/B (112 ± 47 minutes; P < .001). The complication rate was significantly higher in TASC-II C/D (9%) than in TASC-II A/B (3%; P = .014). Cumulative primary patency rates at 1, 3, 5, and 10 years were 90%, 88%, 83%, and 71% in TASC-II C/D and 95%, 91%, 88%, and 83% in TASC-II A/B, respectively. No significant differences were apparent between groups (P = .17; Kaplan-Meier method, log-rank test). In multivariate analysis, lesion length was an independent risk factor for in-stent restenosis (hazard ratio, 1.12, P = .03; 95% confidence interval, 1.01-1.24). CONCLUSIONS Primary stent placement for complex iliac artery occlusive disease provides acceptable long-term outcomes, although the procedure takes relatively longer and is associated with a higher frequency of complications than for simple disease.

Segmental Transcatheter Hepatic Artery Chemoembolization with Iodized Oil for Hepatocellular Carcinoma: Antitumor Effect and Influence on Normal Tissue

PURPOSE Segmental transcatheter arterial embolization (TAE) with use of iodized oil mixed with an anticancer drug, followed by injection of gelatin sponge particles, was undertaken to evaluate its antitumor effect and its influence on normal tissue in patients with hepatocellular carcinoma (HCC). PATIENTS AND METHODS Histologic findings in 12 patients who underwent hepatectomy after segmental TAE were compared with findings on plain radiographs and computed tomographic (CT) scans. Visualization of the portal veins contiguous to the tumor on radiographs and the pattern of iodized oil accumulation in the tumor and vicinity on CT scans after TAE were assessed. RESULTS Complete necrosis of the tumor was achieved in 10 cases (83%), while complete necrosis of daughter nodules and capsular invasion was observed histologically in eight of these 10 patients (80%). The degree of tumor necrosis correlated with the pattern of iodized oil accumulation in and near the tumor. Partial necrosis of normal tissue near the tumor correlated with accumulation of iodized oil. CONCLUSION Segmental TAE may be an excellent therapeutic method for treatment of HCC that is localized in one or a few segmental or subsegmental regions.

Aortic stent-grafting with transrenal fixation : use of newly designed spiral Z-stent endograft

PURPOSE To evaluate the feasibility and efficacy of a newly designed stent-graft placed across the renal arteries for exclusion of abdominal aortic aneurysms (AAAs) with short or tortuous proximal necks. METHODS Among a group of AAA patients treated with endovascular grafting, 5 had tortuous proximal necks and 13 had necks <20 mm (mean 13 mm). In these 18 cases, a 2- to 3-cm uncovered segment of the stent-graft was placed transrenally using a catheter inserted into the renal artery as a guide for graft margin positioning. A newly designed stent-graft was constructed from a custom-made spiral Z-stent covered with a thin-walled Dacron material; the endografts were deployed through 16-F (aortoaortic model) or 18-F sheaths (bifurcated devices). Renal function was assessed by preoperative and postoperative measurement of urea nitrogen and creatinine. Aneurysm exclusion and renal artery patency were evaluated during follow-up using spiral computed tomography and angiography. RESULTS The stent-grafts were correctly placed at the intended site in all 18 patients. Renal function was not affected except transiently in 1 patient who developed bilateral renal artery stenoses 24 hours after the procedure; Palmaz stents were deployed in each renal artery to reestablish satisfactory blood flow. Of the 33 renal arteries crossed by the bare stent-graft segment, all were patent over a mean 14-month follow-up (range 7-24), including the patient with Palmaz stents implanted for postprocedural renal stenosis. Complete aneurysm exclusion was maintained in 15 (83%) of 18 patients; proximal leaks persisted in 3 patients, including 2 with severely angled proximal necks. CONCLUSIONS Transrenal placement of the uncovered leading edge of custom-made spiral Z-stent-based endografts appears feasible and clinically effective in the treatment of AAAs with short or tortuous proximal necks.

Prevalence, factors, and clinical impact of self-expanding stent fractures following iliac artery stenting

PURPOSE To evaluate the prevalence, factors, and clinical impact of self-expanding stent fracture following iliac artery stenting. MATERIALS AND METHODS A review of the endovascular registry database for our department showed 353 patients with occlusive diseases of the iliac artery who underwent stenting between 1997 and 2007. While clinical data and images were retrospectively reviewed for all patients, 165 patients who underwent self-expanding stenting and plain radiograph with >or=6-months follow-up were analyzed. Mean follow-up was 43 months for 305 stents (elgiloy, n = 83; nitinol, n = 222) implanted in 216 iliac arteries. The mean duration until the last imaging study was 38 months. Items concerning prevalence of stent fracture, factors associated with fracture, and outcomes for patients with stent fracture were analyzed. RESULTS Stent fracture was detected in 11 of 216 iliac arteries (5.1%). In stent-based analysis, 11 of 305 stents (3.6%) showed stent fracture, classified as type I in 2 stents, type II in 3 stents, type III in 4 stents, type IV in 1 stent, and type V in 1 stent. Stent fracture was detected in 11 of 222 nitinol stents (5.0%), but no Elgiloy stents. Cox proportional hazards regression model indicated stenting for chronic occlusion as a risk factor associated with nitinol stent fracture (hazard ratio [HR] = 6.09, P = 0.008, 95% confidence interval [CI] 1.59-23.3). Cumulative primary patency rates in iliac arteries with and without fractured stents were 90% and 91% at 8 years (P = .80), respectively. CONCLUSION Fracture of self-expanding stents is rare in iliac arteries, but stenting for chronic occlusion represents a risk factor for fracture. Fractures of stents placed in iliac arteries rarely affect patency.

Segmental embolotherapy for hepatic cancer: keys to success

Transcatheter chemoembolization using Lipiodol (Lp) mixed with chemotherapeutic agents followed by Gelfoam particle injection only to the tumor-bearing hepatic segment (segmental Lp transcatheter hepatic artery embolization) (TAE) was applied to more than 100 patients with hepatocellular carcinoma and metastatic liver cancer. For segmental Lp-TAE, knowledge of the variations of intrahepatic arterial anatomy is important. Furthermore, the catheters and guidewires, volume of Lp, kinds and dose of chemotherapy, preparation of the mixture of Lp and chemotherapy (Lp-emulsion), method of injection of Lp-emulsion and Gelfoam particles, as well as the follow-up computed tomography examination are key items to the success of the procedure and are reviewed.

Deteriorating Consumptive Coagulopathy with Type III Endoleak following Endovascular Repair for Abdominal Aortic Aneurysm Associated with Liver Cirrhosis

Purpose: To report a case of deteriorating consumptive coagulopathy with type III endoleak following endovascular aneurysm repair (EVAR) of the abdominal aorta associated with liver cirrhosis. Case Report: A 72-year-old man with liver cirrhosis developed type III endoleak following EVAR. Spontaneous intramuscular hematoma developed due to deteriorating consumptive coagulopathy induced by type III endoleak and liver dysfunction. Although additional EVAR was performed at 52 months after primary EVAR, the patient died due to multiorgan failure and multifocal hematoma of the muscles and subserosa. Conclusion: EVAR for patients with liver dysfunction and coagulopathy should be considered with great caution. We suggest that prompt and adequate treatment using an endovascular technique or surgical repair should be performed for patients with liver dysfunction, coagulopathy, and turbulent endoleak, even if the coagulopathies are worse compared to before EVAR.