Orbital radiologic parameters of non-syndromic exorbitism patients in comparison with normal population

Abstract

PurposeTo measure orbital dimension of patients with exorbitism and defining criteria for its diagnosis.MethodsTwelve patients with non-syndromic exorbitism (NSE) were compared with 24 control samples by means of computed tomography scan (CT-scan) findings. The proptosis severity, lateral wall length, medial wall length, optic nerve straight length, lateral wall angle, ethmoidal sinus surface area, mid-interorbital distance, anterior interorbital distance, external orbital distance, inter-pupillary distance, and lateral wall curve cord were evaluated in order to define a criterion for NSE.ResultsAmong eleven compared radiological parameters between the study and control groups, five parameters including lateral orbital wall angle (P = 0.02), mid-interorbital distance (P = 0.007), anterior inter-orbital distance (P < 0.001), inter-pupillary distance (P = 0.01), and proptosis severity (P < 0.001) were found to be significantly different between the study groups. Therefore, NSE could be diagnosed with lateral wall angle greater than 41.74°, mid-interorbital distance more than 31.84 mm, and anterior interorbital distance more than 25.90 mm, with a sensitivity of 91% and specificity of 71%.ConclusionsUsing lateral wall angle, mid-interorbital distance, and anterior interorbital distance, we defined the criterion for diagnosis of NSE. Moreover, by focusing on parameters which play a role in developing exorbitism, we can determine the best approach for improvement of aesthetic and functional features of this condition.

3-D cephalometry of the the orbit regarding endocrine orbitopathy, exophthalmos, and sex

“…Utilizing measurements in CT-scans, Baujat et al and Rajabi et al [8,9] did not find significant anatomical differences in EO patients besides slight differences in the lateral orbital angle (angle between the midsagittal plane and the lateral orbital wall) or interorbital distance. These studies, however, were limited by several factors like the use of axial CT slices for 2-D measurements instead of 3-D cephalometry [8,9]. Baujat et al compared two patient groups with exophthalmos (EO and non-EO) [8] whereas Rajabi et al evaluated a small groups of non-EO patients [9].…”

“…These studies, however, were limited by several factors like the use of axial CT slices for 2-D measurements instead of 3-D cephalometry [8,9]. Baujat et al compared two patient groups with exophthalmos (EO and non-EO) [8] whereas Rajabi et al evaluated a small groups of non-EO patients [9]. The number of observed parameters was limited in both evaluations.…”