HSC Section 3 - Trauma, Critical Care and Sleep Medicine

G. Frohwitter et al. / Journal of Cranio-Maxillo-Facial Surgery 46 (2018) 1550 e 1554

Fig. 1. Soft-tissue CT scans in coronal sections, representing the four categories, clockwise, I e IV.

hematoma ( p ¼ 0.345), monocular hematoma ( p ¼ 0.541), sub- conjunctival haemorrhage ( p ¼ 0.556), contusion of the globe ( p ¼ 0.637), impaired vision ( p ¼ 0.787), retinal oedema ( p ¼ 0.075), sphincter laceration ( p ¼ 0.286), or traumatic mydriasis ( p ¼ 0.622). For two further symptoms, namely enophthalmos and a decreased sensibility of the ION, no signi fi cant correlation with the fracture size could be revealed by statistical analysis ( p ¼ 0.114 and p ¼ 0.348; both unpaired two-sample t -tests). When comparing CT- morphological parameters and preoperative ophthalmological re- sults, statistical signi fi cance could be shown for the following (all Fisher's exact tests): diplopia and incarceration of IRM ( p ¼ 0.043); diplopia and displacement of IRM ( p ¼ 0.021); decreased mobility and incarceration of IRM ( p ¼ 0.015); decreased mobility and displacement of IRM ( p ¼ 0.000). Results are displayed in Table 2 . With regard to further clinical symptoms, signi fi cant correlation could be shown for enophthalmos and displacement of IRM ( p ¼ 0.002; Fisher's exact test). For ROC analysis, a cut-off value for the measured fracture size was de fi ned for the occurrence of diplopia ( Fig. 3 ). At a fracture size of 158.9 mm 2 , the maximal Youden index was reached and de fi ned as a cut-off with a sensi- tivity of 92.86% and speci fi city of 33.78%. On taking the CT- morphological-based classi fi cation into account, signi fi cant

Fig. 2. Box plot diagram showing results of a comparison of fracture size of IOFF in mm 2 and the presence of diplopia in preoperative ophthalmological examination. The lines within the boxes indicate the medians; the top edge of each box represents the 75th percentile and the bottom edge represents the 25th percentile. The range is shown as a vertical line (extreme values are not shown).

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