Initial Clinical Experience with Biopolymer-coated Detachable Coils (HydroCoil) in Peripheral Embolization Procedures

Vessel Occlusion using Hydrogel-Coated versus Nonhydrogel Embolization Coils in Peripheral Arterial Applications: A Prospective, Multicenter, Randomized Trial

PURPOSE

To evaluate the safety and effectiveness of hydrogel-coated coils for vessel occlusion in the body trunk.

MATERIALS AND METHODS

A total of 77 patients with various peripheral vascular lesions, treatable by embolization with coils, were randomized (hydrogel group, n = 38; nonhydrogel group, n = 39). In the hydrogel group, embolization of the target vessel was conducted using 0.018-inch hydrogel-coated coils (AZUR 18; Terumo Medical Corporation, Tokyo, Japan) with or without bare platinum coils. The nonhydrogel group received both bare platinum coils and fibered coils without the use of hydrogel-coated coils.

RESULTS

Complete target vessel occlusion was accomplished in 36 patients in the hydrogel group and 37 patients in the nonhydrogel group. No major adverse events were observed in either group. The median number of coils/vessel diameter and the median total coil length/vessel diameter were significantly larger in the nonhydrogel group than in the hydrogel group (P = .005 and P = .004, respectively). The median embolization length was significantly longer in the nonhydrogel group (31.95 mm) than in the hydrogel group (23.43 mm) (P = .002). If no expansion was assumed, the median packing density in the hydrogel group was 44.9%, which was similar to that in the nonhydrogel group (46.5%) (P = .79). With full expansion assumed, the median packing density in the hydrogel group was 125.7%.

CONCLUSIONS

Hydrogel-coated coils can be safely used for peripheral vascular coil embolization, and hydrogel-coated and conventional coils in combination allow for a shorter embolization segment and shorter coil length.

Imaging and endovascular management of traumatic pelvic fractures with vascular injuries

This paper will give an overview of the relevant anatomy, management and imaging, aspects as well as therapeutic aspects of traumatic pelvic fractures with vascular injuries.

Midterm Recanalization after Arterial Embolization Using Hydrogel-Coated Coils versus Fibered Coils in an Animal Model

PURPOSE

To compare angiographic and pathologic effects (ie, occlusion, recanalization) after embolization with Hydrogel-coated coils (HydroCoils) and fibered coils in the renal and internal iliac arteries after 7 days and 1 and 4 months in an animal model.

MATERIALS AND METHODS

Twelve sheep had 1 internal iliac and 1 renal artery randomly embolized with HydroCoils or fibered coils. Renal and internal iliac arteries were embolized with detachable 0.018-inch coils and pushable 0.035-inch coils, respectively. All animals had control angiography performed at 7 days, and 1 and 4 months to assess recanalization before euthanasia. Recanalization and inflammation were evaluated via pathologic examination.

RESULTS

At 1 month, 100% of arteries embolized with HydroCoils were occluded vs 50% of those embolized with fibered coils (P = .004). At 4 months, 80% of arteries embolized with HydroCoils were occluded vs 25% of those embolized with fibered coils (P = .01). Surface of vessel occlusion was significantly greater for iliac arteries (96.7% ± 8.9) than for renal arteries (94.2% ± 5.3; P = .0076). Surface of occlusion of the renal arteries (92.2% ± 5.1) was lower for fibered coils than for HydroCoils (96.8% ± 4.7; P = .0287). Surface percentage of thrombus was significantly lower for HydroCoils than for fibered coils (P < .0001). Surface percentage of thrombus was correlated with surface percentage of recanalization (P = .0181).

CONCLUSIONS

After 4 months, 75% of arteries embolized with fibered coils were recanalized vs 20% of those embolized with HydroCoils (P = .01). Reduced amount of thrombus after embolization with HydroCoils accounted for a reduced rate of arterial recanalization.

Peripheral Embolization Using Hydrogel-Coated Coils Versus Fibered Coils: Short-Term Results in an Animal Model

OBJECTIVES

To angiographically compare the occlusive effects of hydrocoils and fibered coils in the renal and internal iliac arteries at 24 h and 7 days in the sheep model. To determine the occlusive mechanism by hydrocoils and fibered coils by pathological examination.

MATERIALS AND METHODS

Two types of peripheral hydrogel-coated and fibered coils similar in diameter and length were compared. The right and left renal arteries were embolized with 0.018-inch detachable hydrocoils or fibered coils in six sheep. Then, the right and left internal iliac arteries were embolized with 0.035-inch pushable hydrocoils or fibered coils. Arterial recanalization was evaluated at 24 h and at 7 days with angiography. At pathology, the surface percentage of thrombus and embolic material (platinum, Dacron fibers and hydrogel) and the presence of inflammation were assessed.

RESULTS

No difference was found between the coils for recanalization at 24 h or 7 days. For hydrocoils, the surface of occlusion corresponded to thrombus for 42% and coil for 58% including 42% of platinum and 16% of hydrogel, respectively. For fibered coils, the surface of occlusion was composed of thrombus for 69% and of platinum and fibers for 31%. The surface percentage occupied by thrombus was significantly lower for hydrocoils than for fibered coils (p = 0.0047). The surface percentage of embolic was also different between the two products (p = 0.049). No degradation of hydrogel was found at any time points.

CONCLUSION

The percentage of thrombus was significantly less with hydrocoils as compared to fibered coils, which may account for reduced long-term recanalization.

Initial experience with use of hydrogel microcoils in embolization of pulmonary arteriovenous malformations

The purpose of this study is to describe our initial experience with embolization of pulmonary arteriovenous malformations (PAVMs) using hydrogel microcoils. The technical and radiological outcomes were retrospectively reviewed in seven patients with nine simple-type PAVMs (median feeder size 4 mm, range 3-6 mm) who underwent embolization. Hydrogel microcoils were mainly used, and detachable bare microcoils were combined as needed to occlude the terminal feeding artery just before the sac. Of a total of 43 microcoils, 30 (69.8%) hydrogel microcoils were deployed in eight PAVMs with the median number 3.5 (range 2 to 6) per lesion. All hydrogel microcoils were successfully deployed without microcatheter stuck or malposition. In the remaining one small PAVM, only soft bare microcoils were used, however, resulting in recanalization requiring additional coils in the second session. The venous sac was substantially shrunk in all lesions treated with hydrogel microcoils with the median size reduction rate 95.0% (range 81.8% to 99.0%) during the median follow-up period 10 months (range 6 to 18 months). In conclusion, hydrogel microcoils were safely and effectively applied for occluding PAVMs with relatively small feeders.

Achados de imagem e alternativas terapêuticas das malformações vasculares periféricas

As malformações vasculares periféricas compreendem um espectro de lesões que se tornam aparentes no decorrer da vida e podem ser encontradas em praticamente todo o corpo. São pouco comuns e frequentemente confundidas com o hemangioma infantil. Estas doenças são completamente distintas tanto em relação à história clínica como ao prognóstico e às formas de tratamento. Nestas lesões, a história evolutiva e as características do exame físico são de extrema importância para o adequado diagnóstico clinicorradiológico, que guiará a melhor alternativa terapêutica. As classificações mais recentes dividem as malformações vasculares periféricas levando em consideração o fluxo sanguíneo (alto e baixo) e os componentes vasculares envolvidos (arteriais, capilares, linfáticos e venosos). As malformações vasculares periféricas representam um desafio diagnóstico e terapêutico, e exames complementares como tomografia computadorizada, ultrassonografia com Doppler e ressonância magnética, em conjunto com a história clínica, podem trazer informações quanto às características de fluxo e à extensão das lesões. Arteriografia e flebografia confirmam o diagnóstico, avaliam a sua extensão e orientam a decisão terapêutica. Malformações de baixo fluxo geralmente são tratadas por abordagem percutânea e injeção de agente esclerosante, enquanto para as malformações de alto fluxo o acesso é endovascular com uso de agentes embolizantes permanentes líquidos ou sólidos.

Initial experience using N-butyl cyanoacrylate for embolization of lower gastrointestinal hemorrhage

PURPOSE

To report initial experience using N-butyl cyanoacrylate (n-BCA) to control lower gastrointestinal hemorrhage (LGIH).

MATERIALS AND METHODS

From May 2005 to March 2009, 14 patients with LGIH underwent mesenteric angiography and transcatheter arterial embolization using n-BCA. Candidacy was primarily based on the patient's hemodynamic stability and the risk for future LGIH, determined by the presence of at least one of the following risk factors: more than one arterial feeder supplying the bleeding vessel, underlying coagulopathy, or need to resume anticoagulation after embolization. Outcome measures included technical success (immediate postembolic hemostasis confirmed with completion angiography showing no further extravasation of contrast medium), clinical success (postembolic hemostasis in the absence of complications 30 days after the procedure), and clinical failure (recurrence of LGIH necessitating repeat embolization or surgical treatment).

RESULTS

Fourteen patients with active LGIH were treated with n-BCA, with 100% technical success. Two patients had rebleeds resulting in bowel resection. One patient experienced a minor rebleed that spontaneously resolved. One patient died secondary to multiorgan failure in the setting of multiple medical problems. The remaining 10 patients had complete clinical success, experiencing no signs of rebleeding or infarction.

CONCLUSIONS

The results suggest that n-BCA can be a useful alternative embolic agent for the treatment of hemodynamically unstable patients with LGIH when standard microcoiling techniques fail or are not feasible and in patients with coagulopathy.