Controversies in orbital reconstruction—I. Defect-driven orbital reconstruction: A systematic review

Abstract

In the 1980s, computed tomography was introduced as an imaging modality for diagnosing orbital fractures. Since then, new light has been shed on the field of orbital fracture management. Currently, most surgeons are likely to repair orbital fractures based on clinical findings and particularly on data obtained from computed tomography scans. However, an important but unresolved issue is the fracture size, which dictates the extent and type of reconstruction. In other fields of trauma surgery, an increasing body of evidence is stressing the importance of complexity-based treatment models. The aim of this study was to systematically review all articles on orbital reconstruction, with a focus on the indication for surgery and the defect size and location, in order to identify the reconstruction methods that show the best results for the different types of orbital fractures.

Introduction

Orbital defects are one of the most commonly encountered facial fractures because of the exposed position and thin bony walls of the midface area. Orbital fractures may occur alone or in combination with other midfacial fractures, including zygomatic complex fractures, Le Fort II and III fractures, naso-orbito-ethmoidal fractures, and frontal bone/orbital roof fractures. The classic blowout fractures are believed to result from buckling of the orbital rim and retropulsion of the orbital content.¹ Approximately half of all orbital fractures consist of isolated wall fractures,² which primarily comprise orbital floor defects and medial wall fractures.

The management of orbital fracture treatment remains controversial, and a particular subject of debate is the indication for surgery. Most surgeons are apt to repair orbital fractures based on clinical findings and particularly on data obtained from computed tomography (CT) scans, and the key question is, what fracture size needs reconstruction? In the early 1970s, Putterman et al. advocated guidelines with a conservative approach. In particular, the primary recommendation was to wait watchfully and follow the course of the patient's recovery to detect the possible development of post-traumatic diplopia, enophthalmos, and hypoglobus.3, 4 Later insights led to well-defined indications for immediate surgery (Table 1).5, 6

Strong indications for immediate repair include (1) diplopia with radiological evidence of compressed orbital tissue resulting in early ischemic necrosis and oculocardiac reflex,7, 8 (2) life-threatening white-eyed blowouts or trapdoor fractures in children with eye motility disturbances, and (3) radiological evidence of orbital tissue compression9, 10 accompanied by oculocardiac reflex, early enophthalmos, or hypoglobus producing facial asymmetry that affects function and cosmesis.11, 12 In addition, to prevent the fibrosis of injured orbital tissue, early repair within 2 weeks has been proposed for some indications, such as clinically unimproved diplopia with radiological evidence of orbital tissue compression.¹³ Further, several studies have shown that early reconstruction of large orbital defects is essential for good functional results.14, 15, 16 The most difficult management decisions occur with regard to patients with smaller orbital defects. For example, patients with orbital fractures who have good ocular motility and only slight displacement of the orbital content are often treated expectantly. Estimating the benefit of surgery in these cases is challenging, since the behaviour of the soft tissues over time is unpredictable. Thus, the indication for surgical intervention in these types of cases remains controversial.

The clinical outcomes of treatment for the different types of orbital fracture are difficult to compare. The decision to choose a certain implant material must be based on the size and location of the defect and the remaining structural support in combination with clinical symptomatology.¹⁷ In the case of linear fractures with small defects and entrapment of the orbital content, the placement of a membrane may be suitable, whereas in larger defects affecting one wall or multiple walls, a stronger, supportive material may be necessary.¹⁸

Jaquiéry et al.¹⁶ proposed a simplified two-dimensional model to describe these fractures semi-quantitatively in a trefoil-shaped diagram of the internal orbit. Five categories of the extent of the fracture were defined; fractures with a higher classification were associated with a lower accuracy of reconstruction due to repositioning of the globe (Fig. 1). In our experience, the current process of surgical decision-making is rarely influenced by this classification.

The aim of this study was to systematically review all prospective and retrospective clinical trials on orbital reconstruction. Particular focus was placed on the indication for surgery in relation to defect size and location, in order to identify the reconstruction methods that show the best results for the different types of orbital fracture.