Glue Embolization of Aneurysm after Stenting in Canine Carotid Arteries - Technical Feasibility

PURPOSE: Coiling or infusion of embolic materials into a wide necked aneurysm can be performed with stenting. The purpose of our study is to assess the technical feasibility of aneurysm treatment with glue embolization after stenting. MATERIALS AND METHODS: We used four Wallstents for surgically repairing eight canine carotid aneurysms. After confirmation of the aneurysms on the angiogram, we introduced a 6-7 F guiding catheter in order to deploy the stents. After stenting, we passed a microcatheter into the aneurysm lumen through the stent mesh. 28% glue was slowly injected until the glue cast completely filled the lumen. We evaluated the passage of a microcatheter through the stent meshwork, formation of the glue cast and the stents' ability to protection for any leakage of glue. The follow-up angiogram was obtained for two dogs, one to three times until 8 weeks, and then we sacrificed the dogs and performed pathologic examinations. RESULTS: Stenting was successful in all cases except one in which the vessel was occluded because the stent was not completely expanded within the lumen. The microcatheter could not pass through the stent mesh in one aneurysm. The two week follow-up angiogram showed complete occlusion of the aneurysm and a patent carotid lumen in a case after successful stenting and glue embolization without distal migration of glue. Tungsten in the glue was noted to migrate out of aneurysm into the soft tissue of the neck. Histopathologic examination showed successful obliteration and stable organization of the aneurysmal lumen with ingrowth of fibroblasts and a foreign body reaction. In contrast, the aneurysms without the glue embolization being performed showed partially thrombosed aneurysmal lumens that became smaller and indistinct on the 8 week follow-up angiograms. Histopathologic examination showed a disorganized thrombus with numerous recanalizations. CONCLUSION: Glue embolization after stenting could be performed for aneurysm without distal migration of the glue or gluing of the catheter. This concept appears to be useful for applications to the further research and the treatment of aneurysm.

Clinical Application of Stent-Graft Using Gianturco Stent and Poly-tetra-fluoro ethylene (PTFE) in AorticAneurysm

PURPOSE: To evaluate the effectiveness of treatment of aortic aneurysm with endoluminal stent-grafts usingGianturco stent and poly-tetra-fluoro ethylene (PTFE). MATERIALS AND METHODS: In ten patients with aorticaneurysm, eleven procedures were performed using tubular (n=7) or bifurcated (n=4) Gianturco Z-stents covered withPTFE to treat aortic disease (six atherosclerotic aortic aneurysms, four pseudoaneurysms of abdominal aorta inthree patients with Behcet's disease, and one penetrating atherosclerotic ulcer). Spiral CT angiography was usedfor follow-up from 14 days to 31 months (mean, 12 months). The effectiveness of stent-grafts was evaluated duringfollow-up. RESULTS: In all cases, implantation of stent-grafts was technically successful ; in five, perigraftleakage was detected on completion of aortography. On initial post-procedural CT images obtained 4 - 24 days afterinsertion of the stent-graft, complete thrombosis of the aneurysm was seen in seven cases and perigraft leakage infour. Two of the four cases in which leakage was seen on initial CT improved spontaneously during follow-up.Procedure-related thromboembolism occurred in one case, which was managed by thrombolytic therapy without residualsequelae. During follow-up CT, the size of aortic aneurysms of atherosclerotic disease did not change. Thepseudoaneurysms of Behcet's disease decreased and eventually completely disappeared, with only residual periaorticsoft tissue. CONCLUSION: For the treatment of aortie diseases, stent grafting using a Gianturco stent and PTFE isclinically feasible, safe, and effective.

Usefulness of Flexible Covered Stent in Malignant Colorectal Obstruction

PURPOSE: To evaluate the usefulness of flexible covered stent in the treatment of acute colorectalobstruction secondary to colorectal carcinoma. MATERIALS AND METHODS: Flexible covered stents were placed in 11patients with clinical and radiologic signs of acute colonic obstruction secondary to colorectal carcinoma. Thepurposes of stent insertion were pre-operative bowel preparation in seven patients and palliative treatment infour. A fistula was present in two;in one this was between the proximal jejunum and colon, and the other wasrectovaginal. The usefulness of stent insertion for the purpose of preoperative bowel preparation was evaluatedaccording to the feasability and status of bowel preparation, as decided by the operator. Palliative treatment forthe relief of symptoms of acute bowel obstruction was evaluated according to the number and amount of defecation,bowel dilatation in simple abdomen radiography, and the presence of complications. RESULT: Bowel preparation forthe purpose of preoperative bowel cleansing was easy in seven patients;the fecal materials remaining in the colonpresented no problems during surgery. In one of four patients palliative treatment involved a colostomy;this wasdue to recurrent stent obstruction by fecal materials after three months, and in two other patients there wasstent obstruction after two and five months, respectively. The stent in one of four patients who underwentpalliative treatment was removed because of stent migration three days after insertion;the stents in two patientswith fistulas covered the fistulas successfully. Complications after stent insertion were anal pain in threepatients, anal bleeding in three and stent migration in one. CONCLUSION: The flexible covered stent was aneffective device for the relief of acute colonic obstruction secondary to malignant rectosigmoid neoplasia. Itallowed for single-stage operation and covered the fistula. We believe however that for further evaluation of theusefulness of this type of stent in long-term palliative treatment, a larger-scale study is needed.

Recanalization of Chronic Peripheral Arterial Occlusions Using Local Low dose Thrombolysis:in Combination with Angioplasty and Stent Implantation / 介入放射学杂志

Local low-dose thrombolysis, combined with angioplasty or stent implantation, was performed in 5 patients with chronic occlusions of iliac and femoropopliteal arteries. The obstructed segments were found in the external iliac artery (n=2), common iliac and external artery (n=1), femoral artery (n=1), popliteal artery (n=1) and femoropopliteal artery (n=1). The occluded length ranged from 8～25 (mean, 15.3)cm. The estimated duration of occlusions were from 1～24(mean, 9.4) months. Local thrombolysis was performed by using urokinase 56, 000 IU/h, accompanied by heparin treatment (1,000 IU/h) in all patients. The infusion time ranged from 5.5～58(mean, 26) hours. PTA (n=3) and intravascular stent placement (n=1) were immediately performed after thrombolysis. The initial success rate was 100%. Follow-up lasted 2～9 months (mean 5.3 months). This approach was even succesful in a patient with occluded duration up to 2 years. This therapy represents a true altermative to vascular surgery and as first-choice treatment for segmental peripheral occlusions. Thrombolytic procedure dose, interventional indications, other factors and long-term effects were discussed.