When is enophthalmos "significant"?

PURPOSE

It is currently unknown how many measurable millimeters of enophthalmos may be noticeable to an observer. Identifying the amount of enophthalmos present may help to guide patients and clinicians in regard to surgical management of enophthalmos.

METHODS

The Massachusetts Eye and Ear Infirmary Oculoplastics imaging database was used to select 12 photographs of patients with unilateral enophthalmos whose measurements ranged between 1 mm and 8 mm for the study group and 12 photographs of patients who did not have enophthalmos as the control group. Observers were asked to review each of the photographs from both groups and to comment on whether the appearance was normal or abnormal.

RESULTS

There was no statistical difference found when observers reviewed photographs from the control group and patients whose measurements ranged between 1 mm and 2 mm (87%, 83% respondents identifying patients as normal, respectively). Twenty-eight percent of observers found patients with 3 mm and 4 mm of enophthalmos as having a normal appearance (P < 0.001). Ninety-seven percent of observers commented that patients with measurements of 5 mm and 8 mm had an abnormal appearance (P < 0.001).

CONCLUSIONS

Patients with 2 mm and less of measurable enophthalmos had a normal appearance as frequently as those without enophthalmos. Nearly all patients with measurements of 5 mm and greater had abnormal appearances. The point at which enophthalmos becomes detectable lies between 3 mm and 4 mm.