Purpose:
Super-selective intra-ophthalmic artery chemotherapy (SSIOAC) is currently being used for the treatment of retinoblastoma; however, the hemodynamic consequences and toxicities of this treatment are not fully known. We have developed a non-human primate (NHP) model for SSIOAC and reported our clinical observations. To validate our model, we compared ophthalmic artery (OA) diameters between our NHPs and a cohort of children less than 6 years of age.
Methods:
Endovascular cannulation of the right ophthalmic artery was performed three times each in six adult male Rhesus macaques (Macaca mulatta) (median age 10.5 years, median weight 11.6 kg, and median eye measurements 19 x 19 x 19 mm) for 18 total procedures. Angiographic images were obtained and the OA diameter was measured. Post-mortem histologic sectioning with measurements of the OA was performed. For comparison, we performed a retrospective study of computed tomography (CT) and magnetic resonance (MR) angiography images of the head between 2006 and 2011 in children less than 6 years of age. The luminal diameter of the OA was measured at its origin off the internal carotid artery (ICA), the orbital apex, and the mid-orbit.
Results:
In the NHPs, the median angiographic diameter of the six treated right OAs was 1.06 mm (range 0.94-1.56; mean 1.18 ± 0.26 mm). We successfully measured 8 of 12 OAs on histology sections with median diameter of 1.09 mm (range 0.95-1.41, mean 1.15 ± 0.24 mm). We identified 169 consecutive CT and MR angiography studies of the head. In 98 of these pediatric patients (48 females), median age 1.01 years (range 0.005- 5.74; mean 1.36 ± 1.40 years), 186 OAs were measurable at its origin off the ICA with a median luminal diameter of 1.28mm (range 0.82 - 2.0; mean 1.29 ±0.16mm). There was no significance difference in OA diameter between our NHP and pediatric cohorts, p=0.16.
Conclusions:
Ophthalmic artery measurements in our NHPs were similar to those in our pediatric population of patients. We believe our findings validate our NHP model as suitable for testing both the hemodynamic consequences and toxicities of SSIOAC for the treatment of retinoblastoma.
Keywords: retinoblastoma • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • pathology: experimental