Reconstruction of blowout fractures of medial orbital walls

Abstract

To explore the classification of medial orbital blowout fractures (OBF) and the applications of reconstruction materials, to evaluate the efficacy and safety of surgical orbital reconstruction. A retrospective review of 176 cases with medial OBF between January 2008 and January 2011 was conducted, they were classified to group I (pure medial wall fracture, 85 cases) and group II (combined medial and inferior walls fractures, 91 cases). Group I was classified into 3 subgroups, Ia, Ib, and Ic, according to the fractured appearances on CT scans. Group II was classified into 2 subgroups, IIa and IIb, according to the maxillo-ethmoidal bone buttress involved in or not. The operative designs and the choice of reconstruction materials were based on the fractured classification and diplopia. Materials used for repairing included artificial bone plates, titanium meshes and wedge implants. The surgical repairs were undergone via a trans-caruncular approach when necessarily combined with an inferior fornix or lower limbus palpebralis incision. Clinical outcomes and complications were recorded including visual acuity, exophthalmometry, diplopia, hypoglobus and CT scans before and follow-up period. Group II showed more significant enophthalmos than group I (-5.1 ± 0.8 mm vs -2.7 ± 0.7 mm, P = 0.000). Both groups improved after operations (group II: -5.1 ± 0.8 mm vs. -0.7 ± 1.2 mm, P = 0.000; group I: -2.7 ± 0.7 mm vs. 0.1 ± 0.8 mm, P = 0.000). Ocular displacement was more common in group II than in group I (62% vs. 0%, P = 0.000). The hypoglobus was more common in subgroup IIb than in IIa (71% vs. 38%, χ(2) = 8.19, P = 0.004) and significantly improved after operations in subgroup IIb (71% vs. 17%, χ(2) = 38.27, P = 0.000). Diplopia was more commonly noted in group II than in group I (100% vs. 83%, P = 0.000), and was significantly relieved in both groups (group I: Z = -4.475, P = 0.000; group II: Z = -9.751, P = 0.000). Postoperative CT displayed orbital walls reconstructed satisfyingly in 92%. No one was recorded with impaired vision after operation. The important complications were aggravated or new-onset diplopia, under- or over-correction of enophthalmos and ocular superior displacement. A reconstructive operation of medial OBF with proper materials and surgical skills could be helpful for improving diplopia, enophthalmos and hypoglobus. The operations for repairing of medial OBF is efficient and safe.