Efficacy of Retrobulbar Filler Injections for Correcting Enophthalmos Associated with Phthisis Bulbi or Anophthalmos

Abstract

Purpose: To describe the clinical outcome of retrobulbar injection of synthetic fillers to correct enophthalmos associated with phthisis bulbi or anophthalmos.Methods: We retrospectively reviewed the medical records of patients who underwent enophthalmos correction using retrobulbar filler injections at Asan Medical Center between January 2015 and October 2019, and who were followed for at least 6 months. We evaluated the number of injections and amount of filler injected, improvement in enophthalmos, interval between injections, and adverse effects of filler injection.Results: The study enrolled five patients (four females and one male). Two patients had anophthalmos after evisceration and three had phthisis bulbi. Two patients received hyaluronic acid (HA) filler only, one had collagen-polymethylmethacrylate (PMMA) filler only, and two had both fillers. The HA and collagen-PMMA filler volumes per injection were 1.0–1.4 and 0.75–1.0 mL, respectively. The average degree of enophthalmos, compared to the contralateral eye, was 1.8 mm; the amount of enophthalmos correction per 1 mL of filler injection was 1.5 mm for HA filler and 1.4 mm for collagen-PMMA filler. The longest duration of enophthalmos correction was 15 months for HA filler and 25 months for collagen-PMMA filler. There were no significant adverse effects, but anterior migration of HA filler was observed in one case that resolved with hyaluronidase injection.Conclusions: Retrobulbar filler injection is a safe, effective, minimally invasive procedure for correcting enophthalmos in patients with anophthalmos or phthisis bulbi. If HA filler injection shows good outcomes without adverse effects, semi-permanent fillers can be used for long-term maintenance of enophthalmos correction. Further studies with more patients and long-term follow-up are needed to compare the effectiveness of various fillers.