J Korean Ophthalmol Soc.  2015 Feb;56(2):168-173. 10.3341/jkos.2015.56.2.168.

Measurement of Orbital Volume from Facial CT Scans Using a Semi-Automatic Computer Program

• Choi JH
• Park IK
• Choi SJ
• Shin JH

• KMID: 2215998
• DOI: http://doi.org/10.3341/jkos.2015.56.2.168

Abstract

PURPOSE
To measure the orbital volume from facial CT scans using a semi-automatic computer program.
METHODS
Axial and coronal slices of 35 facial CT scans were used to measure the orbital volume. The cross-sectional area was determined from each slice using a semi-automated computer program (MATLAB 2009a). Next, the orbital volume was calculated from serial reconstruction of the cross-sections.
RESULTS
The measured value in males was 26.34 +/- 3.09 cm3 in the right orbit and 26.30 +/- 3.21 cm3 in the left orbit from axial scans, and 26.58 +/- 2.76 cm3 in the right orbit and 26.59 +/- 2.75 cm3 in the left orbit from coronal scans. In females, the values were 23.84 +/- 2.29 cm3 in the right orbit and 23.89 +/- 2.33 cm3 in the left orbit from axial scans, and 24.06 +/- 2.90 cm3 in the right orbit and 24.10 +/- 2.82 cm3 in the left orbit from coronal scans. There was high positive correlation (r = +0.832, p = 0.0001) in measured orbital volume between axial and coronal scans.
CONCLUSIONS
The orbital volume measurement from facial CT scans using a semi-automatic computer program is very useful. This method should prove useful in further studies examining the correlation of orbital volume variation in many ophthalmologic disorders.

Keyword

Facial CT; Orbital volume; Volume measurement

MeSH Terms

Female
Humans
Male
Orbit*
Tomography, X-Ray Computed*

Figure

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  Figure 1. The simplified photographs by the algorithm of the computer program from axial scans (A) and from coronal scans (B).

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  Figure 2. The process of measurement of cross-sectional areas from axial scans (A) and from coronal scans (B). The white arrows are the straight line traced by the examiner. The seed points are remarked with black arrows and the results of automated measurement are remarked with the asterisks.

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  Figure 3. The correlation of measured orbital volume from axial scans with from coronal scans.

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  Figure 4. Automatic outlining of regions. (A) Example data, (B) setting the seed point at the checked ‘9’, and then automatically including the higher numbers around the seed point, (C) different result of the algorithm as setting different seed point checked ‘11’.

Reference

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