Comparison of Fibrovascular Ingrowth between Primary and Secondary Orbital Implants

To compare the rate of fibrovascular ingrowth between primary and secondary orbital implants at varying time intervals after implantation. We prospectively compared the rate of fibrovascular ingrowth between primary and secondary implants by MRI and scinitigraphy in patients who underwent orbital implant surgery, 6 months after the operation. Overall 103 patients underwent hydroxyapatite (HA) implantation including 75 cases of primary and 28 cases of secondary implants. Of 75 patients with primary implants, vascularization was seen in 13 (18%) by 1 month, 33 (45%) by 2 months, 58 (78%) by 3 months, and 70 (94%) patients by 6 months. However in 5 (6%) patients no vascularization was documented by MRI after 6 months. Of 26 cases of secondary implants, central vascularization was seen in 2 (7%) by 1 month, in 8 (29%) by 2 months, in 19 (68%) by 3 months, and in 23 (82%) by 6 months. However, in 5 (18%) cases no vascularization was seen after 6 months. This study demonstrated consistent central vascularization of hydroxyapatite orbital implants by MRI in the majority of cases after 6 months equally in primary and secondary implants.