Study of anatomical variance of the zygomaticofacial foramen and determination of reliable reference points for surgery
Background: Dissection onto the facial aspect of the zygoma is necessary in several maxillofacial procedures. This carries inherent risk of damage to the vessels exiting the zygomaticofacial foramen (ZFF) on the facial aspect of the zygoma.
Objectives: The aim was to compare ZFF anatomy between ethnic groups and sexes, and to determine reliable reference points for surgery.
Methods: 858 zygomatic bones on dry adult skulls were used in the study. Skulls were selected from nine different geographic regions for a comparison between ethnic groups, and a comparison of anatomy between sexes was completed. Each zygoma was examined for the number of ZFF, after which a cross-line laser was used to create two consistent lines from which the ZFF was measured and mapped.
Findings: There were significant differences in number and location of ZFF between ethnic groups, but not between sexes. Of all 858 sides, 1 ZFF was most commonly identified (49.8%). However, foramina number ranged from 0 to 4 per zygoma. Despite this variability over 80% of ZFF bilaterally were found within a 15 mm diameter circle centred at 5 mm anterior to the intersection of lines discussed above. Moreover, over 90% of ZFF fell beyond an arc of 5 mm from the orbital margin.
Conclusion: We present a novel method of identifying a ‘ZFF zone’ within which the majority of foramina lie. This simple technique can be of use in directing osteotomy sites, local nerve blocks, and in preventing iatrogenic damage to the ZFF neurovascular bundle.