O-030 Five year retrospective review of chemosurgery for retinoblastoma: significant technique-related differences and opportunity for improving outcomes

Abstract

Introduction Intra-arterial delivery of chemotherapy (chemosurgery) via selective ophthalmic artery infusion has had an increasing role in the treatment of retinoblastoma due to low morbidity and a dramatic reduction in enucleation. However, technical success and treatment response have varied. This may partially be attributed to ophthalmic artery vasospasm preventing catheterization or causing a reduction in the amount of chemotherapy being delivered to the tumor. At our institution, it was hypothesized that changing to a microcatheter-only approach (described by Gobin et al. in 2015) with intraoperative continuous verapamil flush would improve results. Materials and methods A retrospective review of pediatric patients with retinoblastoma who had been referred to interventional neuroradiology for chemosurgery at our institution in the past 5 years was performed. Data collected included patient demographics, retinoblastoma classification, prior treatments, chemotherapy agents, catheterization technique, fluoroscopy time, evidence of vasospasm, complications, cardiovascular events, technical success, and response on funduscopic examination. Techniques were classified as: Technique A (1.2-Fr or 1.5-Fr microcatheter with continuous verapamil flush for vasodilation, directly advanced without guide through a 2-French groin sheath equivalent) or Technique B (coaxial; 1.5-Fr or 1.7-Fr microcatheter advanced within 4-French base catheter, through a 4-French groin sheath, without verapamil). Statistical analysis was performed to determine if there was a significant difference in mean fluoroscopy times and vasospasm rates based on technique. Results From June 2013 to March 2018, a total of 76 chemosurgery cases were performed on 21 patients to treat 22 eyes. The most recent 21 cases, beginning from September 2017, were performed using Technique A while the remaining 55 cases were performed using Technique B. Mean fluoroscopy times and vasospasm rates are presented in table 1. Technique A had a statistically significant lower mean fluoroscopy time compared to Technique B (unpaired t-test, p=0.001, mean difference 9.2 min, 95% confidence interval 3.8–14.6). Furthermore, 0% of cases using Technique A had associated vasospasm, compared to 10.9% in Technique B (two-tailed z-test, p=0.11). Conclusion The aim of this study was to show that the microcatheter-only approach, when coupled with verapamil, can improve outcomes in chemosurgery for retinoblastoma. These results provide evidence that this technique significantly decreases fluoroscopy time and likely decreases rates of vasospasm. Placement of larger instrumentation in the carotid artery likely necessitates more fluoroscopy for safe manipulation and is more likely to induce vasospasm and possibly cause cardiopulmonary events. The authors believe that additional cases using Technique A will provide the power needed to show that it results in a significant decrease in vasospasm. Further analysis will be performed to determine the effect of this technique and other variables on clinical outcomes, including preservation of retinal function, tumor regression, and time to recurrence. Disclosures C. Yen: None. F. Santiago: None. M. Ghasemi Rad: None. P. Chevez-Barrios: None. C. Herzog: None. P. Kan: 2; C; Stryker Neurovascular, Medtronic. M. Chintagumpala: None. F. Lin: None. D. Gombos: None. S. Chen: None.