Retro-Orbital Intraconal Fat Injection: An Experimental Study in Rabbits

Abstract

Despite adequate treatment, enophthalmos due to intraconjunctival corticosteroid injection and enlargement of the bony orbit after trauma remains a frequent complication. The use of alloplastic material in addressing this problem is restricted because it may result in allergic reactions and is not cost-effective. The use of retro-orbital intraconal injection is the most effective method for maximum augmentation. An inexpensive and minimally invasive alternative that also allows for reoperation when needed would be a preferred intervention. We used 24 white rabbits (New Zealand) in our study. The animals were divided into 2 groups: a fat group and a saline solution group. The first group was subjected to retrobulbar fat injection, and the second group underwent physiologic saline solution injection. The volume of the retrobulbar area was measured and statistically evaluated both before and after the injections. Sonographically measured retrobulbar volumes were then statistically analyzed. When the saline solution and fat groups were compared, no significant difference was observed between the preinjection volumes of the orbits. However, after injection, there was a significant difference between volumes. A statistically significant difference was shown between retro-orbital volumes calculated before the injection in the fat group and volumes calculated immediately after injection and in the following 4 months (right retro-orbital volume of 1.291 cm(3) ± 0.031 cm(3) before injection and 2.656 cm(3) ± 0.040 cm(3) in the fourth month, P < .05). Volume augmentation by fat injection is superior to complicated surgical methods because of the advantages of decreased morbidity, rapid rehabilitation, and ease of reinjection. Using fat tissue as a filling material is more reliable, easier, and cheaper in comparison to other implantable materials.