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Diplopia plays a major role in blow-out fractures of the orbit management dilemma [1]. There have been three suggested causes, as discussed in the literature for diplopia: direct musculo-fascial complex injury [2, 3]; orbital tissue involvement in the fracture defect [4, 5]; and Oculomotor nerve injury [6].

The aim of surgery for blow-out fracture is to restore a full field of functional binocular single vision [7]. This is usually achieved through releasing of the herniated or entrapped orbital tissue in the fracture defect. However, tissue involvement in orbital blow out fracture is not the only influential factor on ocular motility. Accordingly, the outcome of surgery might be unpredictable, as the extent of orbital tissue damage at the time of injury may not be readily determined.

Although making a decision as for the need for surgery in blow out fracture is difficult [8], it is logical to assume that an effective approach for management of diplopia in this type of injury should consider more than one factor. These factors include a preoperative BSV score and of the level of tissue herniation. Recently, the authors published two papers based on 10 year retrospective data. In the first study they found that preoperative BSV score has an important prognostic value in term of postoperative diplopia score and subjective diplopia outcome. This study also showed that patients with BSV >80% score do not benefit from surgery, while patients with BSV <60% benefit from surgery more than other BSV categories in terms of BSV improvement (Figure 1) [9].

Surgery aims to restore single vision through restoring the normal position of the herniated or entrapped orbital tissue, as such, it worth considering the influence of tissue involvement on binocular vision. It appears from the second published study data (Figure 2), that orbital fat herniation, which forms about half of the cases with surgical intervention, has no significant influence when compared to no tissue herniation in relation to diplopia and ocular motility [10]. It is logical to suggest decreasing the number of surgical interventions according to this finding.

It may be difficult on the basis of available studies’ data to suggest definitive guide for the management of blow-out fractures of the orbit. It is possible, however, to provide a figure about the potential benefit of surgery for different levels of preoperative BSV score: Surgical intervention would be more beneficial in terms of postoperative BSV scores for cases with orbital muscle entrapment / muscle herniation with preoperative BSV score <60%. Conservative management might be considered for cases with BSV ≥80% even with orbital muscle herniation. In the 60-80% BSV range, the level of tissue herniation may advise the need for surgical intervention.

Figure1    Figure2

Acknowledgment

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This short communication paper represents the articulation of findings of two recently published articles by the authors. These papers were part of PhD thesis project funded by Almustansiria University and sponsored by NHS and Newcastle University.