NEW INSTRUMENT FOR ORBITAL ANTHROPOMETRY

A new instrument for orbital anthropometry is described. it consists o f the base for a slit-lamp upon which the patient's head rests and rul ers mounted on three independently movable axes, The z-axis probe is u sed to measure sagittal relationships between the corneal apices and p oints on the orbital perimeter. The instrument was tested against a sl iding caliper and its accuracy was found to be within 0.2 mm or 2%. In tra- and inter-observer reliability were assessed by repeated measurem ents of two subjects by three observers. The intra-observer reliabilit y was 0,99, Variations between observers was not significantly differe nt for points orbitale inferius (si), nasion (n), and orbitale superiu s (os), however, there was a statistically significant difference for measurement of orbitale laterale (ol), The correlation between anthrop ometric readings for lateral orbital wall to apes corneal (ol- ac) and CT scans for the same landmarks was assessed. Analysis of variance sh elved no difference between the measurement methods, This anthropomete r is convenient and accurate for measurement of the sagittal orbital-g lobe relationships. A disadvantage is that it cannot be used intraoper atively.