A 35-year-old female presented with constant pelvic pain suggesting pelvic congestion syndrome. Magnetic resonance imaging revealed dilation of the left ovarian vein and vessel embolisation was indicated. Figure 1 (a-c) shows the anatomy of the left ovarian vein upon catheter-based venography, i.e., two twisted branches, each 5–6 mm in diameter. The patient also had a nickel allergy discovered through allergy tests for skin reactions after wearing bracelets and rings. While rare, reactions to implanted devices in patients with metal allergies (including nickel) exist in the literature [2–4]. Furthermore, the metallic content of endovascular devices is not always apparent [5]. Therefore, the use of a shape memory polymer vascular plug was considered a reasonable strategy to minimise the potential of an allergic reaction to implanted metallic embolic material in a patient with a known hypersensitivity, and especially in an ovarian vein case, where a large amount of embolic material is often implanted. The IMPEDE-FX Embolization Plug is comprised solely of a shape memory polymer plug and a platinum/iridium proximal marker. Figure 2 shows the dimensions of the plug used in this case (IMP-FX-12). The volume of the shape memory polymer material in this size is approximately 1.25 mL. The left ovarian vein was accessed with a 90 cm 5 Fr Flexor Ansel Guiding Sheath (Cook Medical, Bloomington, Indiana, USA) and a .035 Radifocus Guidewire M (Terumo Corporation, Tokyo, Japan) using standard techniques via the right femoral and left renal vein. The first ovarian vein branch was accessed and the first IMPEDE-FX Embolization Plug was pushed into the vessel just proximal the vessel twist. The twist in the vessel branch minimised the likelihood of reflux-induced distal (caudad) device migration while the shape memory polymer was undergoing initial expansion. The catheter was retracted 3–4 cm from the device to allow blood flow into the vascular plug structure and to deliver contrast injections without putting unnecessary pressure on the vessel. Holding the catheter in place also mitigated any potential proximal (cephalad) migration risk, although this was not observed. Approximately 10 minutes later, and after initial expansion of the first plug was confirmed by contrast injection, a second shape memory polymer plug was deployed into the same branch just proximal to the first. Again, expansion was confirmed prior to removing the catheter in order to mitigate any potential proximal migration risk. The other branch was accessed and two more shape memory polymer plugs were deployed with a similar technique.
It was not necessary to embolise the trans-pelvic varices with sclerosant. No other embolic material was used in the treated vessels. Ten minutes after deployment of the fourth plug, plug expansion was confirmed by contrast injection and the case was finished using standard techniques. Figure 3 shows the final case image. Follow-up magnetic resonance imaging at 4 months post procedure showed a sustained occlusion of the treated vessels and the patient showed no signs of allergy to the implanted material.