Internal iliac embolization

Internal Iliac Artery Embolization in the Stent-Graft Treatment of Aortoiliac Aneurysms... 

The advance of endovascular therapy for aorto-iliac aneurysmal disease has also brought about yet another flourishing application of embolotherapy. Embolization of the internal iliac artery plays an important adjunct initial modality to allow endovascular treatment of aortic aneurysms with extension into the common iliac arteries [78-80], It also plays an crucial role in the secondary management of complications related to endoleaks [81-84],... 

A spectrum of end-organ ischemic complications can occur with embolotherapy. Bowel infarction can complicate splanchnic embolization targeting bleeding or could result from inadvertent non-target embolization from an upstream source [88]. Gallbladder infarction or bile duct necrosis can complicate hepatic artery embolization or che-moembolization [89, 90]. Splenic abscess and overwhelming sepsis can occurs following splenic embolization [91]. Skin necrosis and nerve injury have been reported as a result of ethanol embolization of vascular malformations [53, 54]. Buttock muscular necrosis, buttock claudication and sexual dysfunction can occur as a result of internal iliac branch embolization, especially when distal or bilateral [92-95]. 

After completion of the primary embolization procedure, it is important to check other potential collateral pathways. For example, profunda femoris and contralateral internal iliac arteries are injected following embolization of an internal iliac bleeding source. 

Engelke C, Elford J, Morgan RA, Belli AM (2002) Internal iliac artery embolization with bilateral occlusion before endovascular aortoiliac aneurysm repair - clinical outcome of simultaneous and sequential intervention. J Vase Intervent Radiol 13 667-676... 

Schoder M, Zaunbauer L, Holzenbein T, et al. (2001) Internal iliac artery embolization before endovascular repair of abdominal aortic aneurysms frequency, efficacy, and clinical results. AJR Am J Roentgenol 177 599-605... 

Ramirez Jl, Velmahos GC, Best CR, Chan LS, Demetriades D (2004) Male sexual function after bilateral internal iliac artery embolization for pelvic fracture. J Trauma 56 734-739... 

Su WT, Stone DH, Lamparello PJ, Rockman CB (2004) Gluteal compartment syndrome following elective unilateral internal iliac artery embolization before endovascular abdominal aortic aneurysm repair. J Vase Surg 39 672-675... 

Kritpracha B, Pigott JP, Price Cl, Russell TE, Corbey MJ, Beebe HG (2003) Distal internal iliac artery embolization a procedure to avoid. J Vase Surg 37 943-348... 

Pisco JM, Martins JM, Correia MG (1989) Internal iliac artery embolization to control hemorrhage from pelvic neoplasms. Radiology 172 337-339... 

Hare WSC, Holland CJ (1983) Paresis following internal iliac artery embolization. Radiology 146 47-51... 

The IMA supplies colon distal to the splenic flexure including the descending colon, sigmoid colon, and rectum. When embolizing rectal branches off of the superior hemorrhoidal branch of the IMA, one must remember the rich collateral network around the rectum with middle hemorrhoidal branches arising from the internal iliac arteries. The internal iliac arteries should be studied after embolizing a rectal branch to exclude the possibility of collateral flow to the bleeding site. 

Differences in segmental arterial supply probably also impact on the risk of infarction. The rectum is likely to tolerate embolization better than other regions since it has a dual blood supply with the superior hemorrhoidal artery off of the inferior mesenteric artery and middle hemorrhoidal arteries arising from the internal iliac circulation. This translates into increased potential for collateral blood flow and thus decreased risk of ischemia. The cecum may be more prone to ischemia since there is not a well developed arcade along the mesenteric border of the cecum and instead there are separate anterior and posterior cecal branches. The tissue supplied by these individual branches may be more susceptible to ischemia and in fact infarction of the cecum (even after microcatheter embolization) has been reported [13]. 

Fig.9.3a,b. Right iliac angiogram showed collateral pathways from the artery supplying the round ligament after embolization of both right internal iliac and uterine arteries... 

For this reason, when an embolotherapy is planned we recommend immediate cessation of prostaglandin Ej agonist infusion. In case of arterial spasm at the ostium of the uterine artery, the use of a coaxial system with a microcatheter is then required. It is possible to successfully catheterize the distal part of the uterine artery in most cases. In these circumstances, the preferred embolic agent is the one that can be easily delivered through a microcatheter, such as PVA (Polyvinyl alcohol) or Embospheres. We prefer to use particles with larger diameters, such as Embospheres 700-900 mg. Even if these particles are used for the above-mentioned reasons, additional Gelfoam embolization of internal iliac arteries is performed because of the extensive collateral pathways of the female pelvis. 

In the absence of arterial spasm, embolization with Gelfoam pledge of both uterine and internal iliac arteries is always performed in order to obtain a bilateral proximal and distal embolization to prevent rebleeding. Even with Gelfoam pledge, we always use large-cut sizes to prevent embolization that is too distal. Embolization with coils is not per-... 

Since the first embolization of PPH performed by Brown in 1979, the reported success rate in 138 patients over a 20-year period was as high as 94.4% [35-43]. To date, 160 patients have been treated at our institution (the first author s institution) by selective uterine and/or internal iliac arteries embolization for intractable bleeding following delivery. Despite the variety of the etiologies and risk factors in our series, no maternal deaths were observed. The main cause of hemorrhage was related to uterine atony, with an incidence of 75%. Cesarean delivery... 

Fig.9.7a-d. Angiogram of right internal iliac artery demonstrates contrast media extravasation (double arrow) superselective catheterization using microcatheter and embolization with microcoils (arrows). (Courtesy of Patrice Garance)... 

Our approach to patients with abnormal placentation is to selectively embolize bilateral uterine and internal iliac arteries as soon as possible after delivery. Using the embolization technique, we obtained results similar to that of the prophylactic in controlling PPH, but without the risk of radiation to the fetus. 

The selective transcatheter technique for embolization of uterine and/or internal iliac arteries in the management of intractable bleeding after delivery is safe and effective. In order to create the best hemodynamic and clinical conditions for this therapy, a strong multidisciplinary collaboration is essential to optimize clinical outcomes. 

Dubois J, Garel L, Grignon A, Lemay M, Leduc L (1997) Placenta percreta balloon occlusion and embolization of the internal iliac arteries to reduce intraoperative blood losses. Am J Obstet Gynecol 176 723-726... 

Collins CD, Jackson JE (1995) Pelvic arterial embolization following hysterectomy and bilateral internal iliac artery ligation for intractable primary post partum hemorrhage, gin Radiol 50 710-713... 

Fig. 10.5.3a-e. A 37-year-old patient with symptomatic fibroids. She was offered a hysterectomy as the only alternative. a,b Left uterine artery catheterization and embolization. The final angiogram at the termination of the embolization demonstrates the left ovarian artery (b). c Right internal iliac angiogram shows the absence of righf ufer-ine artery, d Catheterization of fhe righf ovarian arfery demonstrafes the supply to the uterus by this artery, e Distal catheterization and embolization of fhe ovarian arfery wifh successftil clinical oufcome... 

The same multipurpose shape catheter is then directed into the right ovarian vein. A right ovarian venogram and, if needed, embolization are performed in the same fashion as described for the left. If the ovarian venograms are negative, then bilateral internal iliac venograms are performed as rarely isolated pudendal vein reflux will cause symptomatic pelvic varicosities (Figs. 11.7a,b). We do not routinely study the internal iliac veins if ovarian vein reflux is found however, other interventionists do this routinely [34]. 

Clinical outcomes appear similar when the internal iliac veins are routinely occluded. Venbrux et al. (1999) followed 56 women for a mean of 22.1 months after embolization with coils and sodium morulate [36]. The internal iliac veins were also occluded in 43 of 56 patients at a separate procedure 3 to 10 weeks after ovarian vein embolization. The technical success rate was 100%. Three patients developed recurrent varices, two of whom were treated with repeat embolization. Using visual analogue scales to measure pain, a mean 65% decrease in VAS score was recorded. Two patients (4%) reported no change in their symptoms, no patients had worsening of their pain after embolization. 

Fig. 13.4a-f. Posttraumatic HFP with bilateral fistulae. a Left internal iliac artery angiography shows a fistula, b Selective left IPA. c After closure of the fistula with gelatin sponge, d Selective right IPA shows a second fistula, e Microcatheter in superse-lective position, f End result after embolization with gelatin sponge. Patient had a full recovery and regained normal erectile... 

The occlusion of the iliac artery is usually sufficient to treat the leak. However, in cases of long-term type IC endoleak, many outflow vessels may have developed and the leak may communicate with multiple lumbar arteries and the IMA. These enlarged vessels might be source of late type II endoleak. Thus, we usually embolize both the outflow vessels and the sac before occluding the iliac artery. Another attractive technique to achieve the occlusion of the common iliac artery is to perform an endovascular internal to external iliac artery bypass using stentgraft. This technique can allow the exclusion of the common iliac preserving the internal iliac artery. 

As mentioned above, status of the internal iliac arteries is an important anatomic consideration in the treatment of aortoiliac aneurysms. Indications for embolization of IIA in association with EVAR include aneurysm of the IIA or ectatic or aneurysmal common iliac artery (CIA) involving the origin of IIA. Additionally, extension of stent-graft into the external iliac artery (El A) may become necessary if the CIA is judged to be too short for adequate or safe anchoring of the device or if there is a distal type-I endoleak. This will lead to loss of antegrade flow in the IIA. 

Fig. 15.1. a Contrast. enhanced CT of abdomen shows an abdominal aortic aneurysm with patent lumbar and inferior mesenteric arteries. Patient developed a type 11 endoleak after endograft placement, b Non-contrast CT shows glue embolization of the lumbar arteries and the sac through a branch of the internal iliac artery... 

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