A comparison of particulate and onyx embolization in preoperative devascularization of juvenile nasopharyngeal angiofibromas.

INTRODUCTION: Juvenile nasopharyngeal angiofibromas (JNAs) are hypervascular tumors that may benefit from preoperative devascularization to reduce intraoperative blood loss (IBL). The purpose of this study was to compare transarterial particulate embolization (TAPE) with the direct percutaneous embolization (DPE) technique using ethylene vinyl alcohol (Onyx, ev3, Irvine, CA) for the preoperative devascularization of a JNA. METHODS: We retrospectively reviewed 50 consecutive JNA resections since 1995 for which preoperative embolization was either transarterial with particulate material (n = 39) or DPE (n = 11) using only Onyx. The IBL, transfusion requirements, operative time, and length of hospital admission were compared between the two groups. RESULTS: The mean IBL was 1,348.7 ± 932.2 mL particulate group, 569.1 ± 700.7 mL Onyx group (one-tailed Student's t test p = 0.003). The mean unit of packed red blood cells was 1.56 ± 2.01 units particulate group, 0.45 ± 1.04 units Onyx group (p = 0.009). The relationship between embolization type and IBL remained significant or strongly correlated when accounting for the Fisch stage of the tumor (p = 0.010 and p = 0.056, respectively, by a multivariate least squares fit; alternately p = 0.0003 and p = 0.023, respectively, in the subset of patients with Fisch stage III tumors only). We also found that the proportion of resections for which an endoscopic approach could be used was significantly higher in the Onyx group than the particulate group (81.8 and 18.2 %; Pearson p = 0.0002), and this was also significant both in our multivariate nominal logistic fit (p < 0.001) and in the subset of patients with Fisch stage III tumors (p = 0.018). CONCLUSION: Pre-operative DPE with Onyx of a JNA when compared to TAPE significantly decreased IBL and RBC transfusion requirement during surgical resection. The proportion of surgical resections performed from an endoscopic approach was higher in the DPE Onyx group, which may have affected the results.

A comparison of particulate and Onyx embolization in preoperative devascularization of carotid body tumors.

INTRODUCTION: Preoperative embolization of a carotid body tumor (CBT) is a useful adjunct prior to surgical excision because it decreases operative blood loss and improves surgical outcomes. Traditionally, this is performed by transarterial particulate embolization (TAPE). More recently, direct percutaneous embolization (DPE) with Onyx is recognized as a promising technique for preoperative embolization. We compared these two techniques in patients treated for CBTs at our institution. METHODS: We retrospectively reviewed cases of preoperative devascularization of CBT from 1 January 1995 through 1 September 2012. Patient cases were placed into two groups: TAPE and DPE. Operative blood loss, operative length, angiographic devascularization, embolization procedure complications, operative transfusion requirements, postoperative hospital stay, intensive care unit (ICU) stay, and procedure-related mortalities were compared. RESULTS: A total of 17 patients underwent preoperative devascularization of their CBT with TAPE technique and ten patients using the DPE technique with Onyx. Average operative blood loss was significantly higher in the TAPE group (Mann-Whitney U test, p = 0.04). Operative time was also higher, although this difference was not significant. Two patients required intraoperative blood transfusions in the TAPE group while none required transfusions in the DPE group. There was no significant difference in ICU stay or length of hospitalization. One serious embolization procedure complication occurred in the TAPE group and none in the DPE group. CONCLUSION: Operative blood loss in the DPE group was significantly less than the TAPE group. Blood transfusion requirement, operative time, and complications were less in the DPE group, although they did not reach statistical significance.