Analysis of contemporary tools for the measurement of enophthalmos: a PRISMA-driven systematic review

Enophthalmos has many causes, and serious post-traumatic cases indicate the need for operation. Such diagnoses should be made objectively, and a robust method for quantifying the degree to which the globe has been displaced is key. Current methods of measurement, however, have long been considered unreliable and inconsistent, in particular with regard to interobserver variability. The aim of this paper therefore was to review all these methods systematically, to analyse their reliability, and to compare them with others. The paper also includes a proposed protocol for the accurate and reliable measurement of protrusion of an eye, which aims to standardise the assessment of patients and to create a uniform approach that will enable the selection of those who are most likely to benefit from surgical treatment. Analysis of the data showed that computed tomographic (CT) exophthalmometry is the most reliable, followed by the Mourits' exophthalmometer, which performed better than the other clinical methods. In the acute phase of orbital blowout fractures, the measurement of herniated tissue through a fracture defect may give a good prediction of the degree of enophthalmos that is likely to occur without surgical correction. Measurement of the herniated volume and CT exophthalmometry should be the foundation for diagnosis and the planning of treatment. Three-dimensional imaging or Mourits' exophthalmometers (which are reliable non-radiological methods) could be used in a follow-up protocol.