Microcatheter embolization of non-neurologic traumatic vascular lesions

Embolization for the treatment of renal artery pseudoaneurysm following surgical nephrolithotomy: A case report

Renal artery pseudoaneurysm is a rare but serious complication following trauma or renal surgery, leading to hematuria and deterioration of renal function. Selective renal artery embolization is an interventional radiologic procedure that can be used to treat these complications. We report a case of a 62 years old woman who developed hematuria following a segmental renal artery pseudoaneurysm after staghorn stones surgical nephrolithotomy, a selective embolization with steel coils was successfully performed.

Visceral arteriography in trauma

The nonoperative management including endovascular treatment of traumatic injuries to most abdominal solid viscera is increasingly gaining acceptance as treatment of choice in a select group of patients. The indications, techniques, and principles of endovascular management of hepatic, splenic, and renal injuries are discussed in this review.

New embolization microcoil consisting of firm and flexible segments: preliminary clinical experience

PURPOSE

To describe the preliminary clinical experience with a new embolization microcoil.

METHODS

The microcoil was made of a platinum coil spring, and consisted of firm and flexible segments. The firm segment functioned as an anchor and the flexible segment was well compacted to occlude the arteries. No Dacron fiber was attached. Seventy-one new microcoils were placed via microcatheters in 28 visceral arteries of 17 patients. Two other types of microcoils with Dacron fibers were used together in 8 arteries.

RESULTS

Sixty-nine new microcoils were placed and compacted successfully. Two coils were misplaced; one was retrieved and the other was left in the migrated artery, which remained patent 5 months later. All 28 arteries were occluded, and the goals of intervention were achieved successfully in all 17 cases.

CONCLUSION

The new microcoils anchored and compacted well in the arteries. The clinical feasibility of this coil design was confirmed. The additional use of other types of microcoils with Dacron fiber was necessary to obtain rapid occlusion in some cases.

Transcatheter arterial embolization in a hemodynamically unstable patient with grade IV blunt liver injury: is nonsurgical management an option?

The prevalence of liver injury in patients who have sustained blunt multiple trauma was reported to range from 1 to 8%. Because previous mortality rates were as high as 50-80% for severe hepatic injury, the choice of treatment was under intensive investigation. Whereas nonsurgical management was the standard treatment for the hemodynamically stable patient, there is no consensus on how to treat hemodynamically unstable patients. This report details the case of a patient who sustained blunt multiple trauma, resulting in a grade IV liver injury, graded according to the American Association for the Surgery of Trauma (AAST) Liver Injury Scale. With massive fluid and blood resuscitation, the patient was stable enough to be managed nonsurgically. With transcatheter arterial embolization (TAE), the left and right hepatic arteries were embolized with coils, which allowed for a good recovery. We hypothesize that TAE can be used in the hemodynamically unstable patient who responds to rapid fluid resuscitation and blood transfusion. We caution that there is insufficient evidence until now and would therefore not make any recommendations; however, we would question the need for surgery in unstable patients with this kind of injury in the future.

Connection Between a Long-standing Traumatic Arteriovenous Fistula and Development of Aneurysmal Disease

Long-standing peripheral arteriovenous fistulas (AVFs) are always accompanied by ectasia of the proximal arteries. In the literature, traumatic fistulas of the lower limbs are frequently reported to be associated with iliac and even infrarenal aortic aneurysms; however, no study dealing with associated visceral aneurysms has been published. We report a case in which a traumatic AVF was accompanied by the late development of not only an infrarenal aortic aneurysm but also both superior mesenteric and right renal artery aneurysm. No causal relationship may be inferred between the tibial fistula and the other aneurysms, but this previously unreported finding does raise the question of a possible connection.

Optimum iodine concentration of contrast material through microcatheters: hydrodynamic analysis of experimental results

It is important to increase the iodine delivery rate (I), that is the iodine concentration of the contrast material (C) x the flow rate of the contrast material (Q), through a catheter to obtain high quality arteriograms. The iodine delivery rate varies depending on the iodine concentration of the contrast material. The purpose of this study is to estimate the optimum iodine concentration (Copt) of contrast material (i.e. the iodine concentration at which I becomes maximum) through a microcatheter of a given length (L), inner diameter (D) and injection pressure (P). Iohexol, ioversol and iopamidol of 11-12 iodine concentrations (140-350, 160-350 or 160-370 mg cm(-3)) at 37 degrees C are used. I and Reynolds number (Re) of the flow of each contrast material through four microcatheters (0.49-0.68 mm in inner diameter, 1000-1500 mm in length) at injection pressures of 1.38, 2.76, 4.14 and 5.52 x 10(6) Pa (200, 400, 600 and 800 pounds per square inch) are obtained experimentally. The relationships between I and C and between I and Re are examined for each catheter and injection pressure. Copt is 160-280 mg cm(-3) for iohexol, 180-280 mg cm(-3) for ioversol and 200-300 mg cm(-3) for iopamidol. I becomes maximum when Re approximates the critical Reynolds number (Re approximately 2300). Utilizing this principle, we can estimate Copt and its flow rate through a microcatheter of a given L, D and P.

Successful treatment of coronary artery perforation in an abciximab-treated patient by microcoil embolization

We describe a case of type 2 coronary artery perforation in a 73-year-old man undergoing coronary artery rotablation and stenting with abciximab therapy. The coronary artery perforation was successfully treated by coil embolization with Trufill pushable coils made from platinum alloy and synthetic fibers to promote maximum thrombogenicity.

Microcatheter embolization of hemorrhages

PURPOSE

To evaluate the efficacy of embolotherapy using microcatheters in patients with hemorrhage from various locations.

METHODS

Among 29 patients there were 13 with severe epistaxis, 7 with gastrointestinal bleeding, 4 with hemorrhage in the kidney, 4 with bleeding in pelvic organs and 1 with bleeding in the shoulder region. In all cases, a Tracker-18 or Tracker-10 microcatheter was advanced coaxially through a 4.1 Fr guiding catheter in order to reach the bleeding site as distally as possible. Polyvinyl alcohol microparticles and/or platinum microcoils were used as embolic material.

RESULTS

The bleeding was stopped in 90% (26 of 29) of cases. In 66% of cases the treatment was curative, in 7% preoperative, and in 17% palliative. There were 3 clinical failures.

CONCLUSION

Microcatheter embolization is an effective and safe means of managing different kinds of hemorrhage of various causes from a variety of sites.

False aneurysm of the inferior gluteal artery following penetrating buttock trauma: case report and review of the literature

The case of a 28-year-old man who presented with a false aneurysm of the inferior gluteal artery 3 months after a penetrating wound to the buttock is reported. Percutaneous transcatheter embolization was unsuccessful. At operation, abdominal access was used for control, with a gluteal approach to provide exposure of the aneurysm. The presentation and management of patients with this pattern of injury are discussed, and the relevant literature reviewed.

Microcatheter embolization of arteriovenous fistulas in the subclavian region. Report on three cases

PURPOSE

The retrospective evaluation is presented of 3 patients treated with endovascular embolization of arteriovenous fistulas (AVFs) in the subclavian region.

MATERIAL AND METHODS

Three patients, 2 women and one man, were treated endovascularly in local anesthesia using microcatheters and fibered platinum microcoils. Two patients were asymptomatic and one had unexplained chest pain.

RESULTS

All 3 AVFs were successfully occluded. One coil slipped through the fistula into the pulmonary circulation but caused no clinical sequelae.

CONCLUSION

AVFs in the subclavian region can be treated by using microcatheters and fibered platinum microcoils.

Repositionable vascular occluder: experimental comparison with standard Gianturco coils

PURPOSE

To evaluate the efficacy and recanalization rates of a newly designed vascular occlusion device.

MATERIALS AND METHODS

The self-expanding vascular occluder was braided from fine nitinol wires and filled with polyester fibers. The device was delivered through a 6-F polyethylene introducing sheath with use of a delivery cable with a microscrew adaptor. Comparison was made between one occlusion plug and two Gianturco coils placed in the corresponding contralateral arterial segment in nine dogs and six pigs. The mean diameter of the targeted vessels was 4.8 mm +/- 0.8. Two animals were killed immediately after occlusion, and the remaining 13 animals underwent follow-up angiography at 1 week and/or 1 month, after which the animals were killed and the vessels were explanted for gross and histopathologic examination.

RESULTS

Significantly shorter time-to-occlusion was achieved with the nitinol plug compared with two Gianturco coils (1.73 minutes +/- 1.28 vs 5.73 minutes +/- 6.18; P = .021). The recanalization rate at 1 month was also significantly lower (36.4% vs 81.8%, P = .027). The occlusion time was strongly dependent on the target artery diameter with Gianturco coils (R = .79, P = .0007), and not with the nitinol plug.

CONCLUSION

The nitinol vascular occluder appears highly effective and reliable, with one plug resulting in significantly faster and longer lasting occlusions compared with two Gianturco coils. The new device can be repositioned prior to release, therefore allowing optimal positioning.

Interlocking detachable platinum coils, a controlled embolization device: early clinical experience

PURPOSE

To present the early clinical experience of a new mechanically controlled-release embolization device--the interlocking detachable coil (IDC)--in complex embolization outside the head.

METHODS

IDCs were used only when conventional embolization techniques were considered too risky or unsafe. The coils consist of unfibered coiled platinum (0.012 inch), mechanically connected to a pusher wire and deployed through a Tracker 18 catheter. IDCs come in a range of diameters (2-8 mm) and lengths (1-30 cm).

RESULTS

A total of 87 IDCs were used for 27 procedures in 25 patients (mean 14.5 years) to occlude 31 arteries or vascular lesions. Control of the coil and its release were satisfactory and all coils ere fully retrievable up to the point of deployment. Two IDC coils embolized inadvertently but were retrieved; there were no other complications. The IDC coils could not be satisfactorily placed one high-flow arteriovenous (AV) fistula, and in another case there was a small residual fistula. Occlusion was produced in 29 of 31 lesions. Ancillary techniques were needed in 5 patients: temporary balloon occlusion in 2 and 0.038-inch coils in 3.

CONCLUSION

The IDC coil is an effective device that allows controlled embolization to be performed, especially in aneurysms and in high-flow AV fistulas in children.

Superselective endo-vascular treatment of renal vascular lesions

Embolization with platinum micro-coils delivered through the Tracker-18 micro-catheter was performed in 6 patients when peripheral selective catheterization with standard angiographic catheters was not possible. The patients had a total of 7 peripheral renal vascular lesions (3 arteriovenous fistulas, 2 false aneurysms, 1 direct vascular trauma and 1 arteriovenous malformation). In all patients we initially used platinum micro-coils as the embolic agent. Two patients required repeat embolization with glue. Endo-vascular treatment was technically successful in all cases and no complications were encountered. There was no renal parenchyma infarction in 3 patients and small peripheral infarctions (10 to 15% of the renal parenchyma) occurred in 3. Super selective endo-vascular treatment with a variable stiffness catheter is safe and useful technique when classical methods of embolization are not possible.

Correction of deteriorating renal function by superselective embolization of an arcuate renal artery pseudoaneurysm

We performed superselective embolization of an iatrogenic pseudoaneurysm of the right kidney that was causing hematuria and deterioration of renal function in a patient with chronic renal failure. An arcuate artery was embolized with absorbable gelatin sponge and a straight embolization wire without significant loss of renal vascularization, thus restoring baseline renal function. To our knowledge the clinical and technical aspects of our case are unique. The technique is described.