Packing density and long-term occlusion after transcatheter vessel embolization with soft, bare-platinum detachable coils

Abstract

Objective: The objective of this study was to examine packing density and long-term recanalization rates after embolization with soft, bare-platinum ruby coils in the gastroduodenal artery (GDA). Materials and Methods: Retrospective case review of patients with hepatic malignancy who underwent coil occlusion of the GDA for radioembolization or hepatic arterial infusion chemotherapy between November 2013 and July 2018. Data on patient demographics, GDA diameter, length of coil pack, and distance between GDA origin and most proximal coil were collected. Packing density was calculated as the ratio between the volume of inserted coils and the volume of the vessel area that were filled with coil. The primary outcome was the rate of GDA recanalization, determined by review of hepatic arteriograms at follow-up. Results: Long-term occlusion free of recanalization was observed in 97.8% (88/90) of patients over a median follow-up time of 13.4 ± 11.3 months. Median vessel packing density was 55% (interquartile range 41–71) and procedural technical success was achieved in 100% (90/90) of patients. Of the 90 patients (72 men; mean age 63.8 ± 7.5 years), mean GDA diameter was 4.0 ± 0.8 mm and the proximal coil distance from GDA origin was 8.6 ± 3.0 mm. Mean coil pack length was 21.2 ± 7.6 mm. Recanalization occurred in 2.2% (2/90) of patients. No increase in recanalization rates with distal coil placement was observed. Conclusions: The study demonstrates high levels of technical success and low rates of recanalization (2.2%) when high packing densities (55%) are achieved using soft, bare-platinum ruby coils. The rate of recanalization at follow-up compares favorably to previously reported literature.

In Vitro Head-to-Head Comparison of Flow Reduction between Fibered and Non-Fibered Pushable Coils

“…The volume of the inserted coils was calculated using the formula for the volume of a cylinder, assuming the coil to be a thin and infinitely long cylinder (Volume=π×radius 2 ×length). For the calculation of the vessel volume, we measured the length of the coil-filled segment using two-dimensional angiography [ 7 ].…”

“…For the calculation of the vessel volume, we measured the length of the coil-filled segment using two-dimensional angiography. 7 Statistical analyses were conducted using the Wilcoxon signed-rank test. A two-sided P-value of 0.05 was used in this study.…”

“…[2][3][4] Although detachable coil technology has become popular in our neurointerventional field, conventional pushable coils still play a role in various vascular embolization procedures. [5][6][7][8] In neurovascular procedures, such as venous sinus procedures, various arteriovenous fistulae, trapping of an artery, and other embolization procedures, pushable coils are still preferred not only due to their cost-effectiveness but also because they offer a higher packing density compared to thinner coils. 3,9,10 In this sense, it is meaningful to understand the basic characteristics of conventional embolization coils, especially for beginners.…”

Small Number of Coils With Extended Length in the Endovascular Treatment of Cerebral Aneurysm: Experience of 108 Cases in a Single-Center

“…In coherence, using computer-generated aneurysmal models to simulate hemodynamics, recurrent aneurysms had significantly lower coil packing density and higher uncoiled aneurysmal volume, the latter of which was an independent predictor for recurrence [3]. Vogler et al corroborated this, demonstrating a high success rate of occlusion from the use of high-packing density coils [27]. However, a study in Japan found that aneurysm volume (odds ratio (OR): 15.3; P < 0.001) and residual volume (OR: 30.9; P < 0.001) were significant predictors for recanalization, not packing density (OR: 0.98; P = 0.341) [6].…”