TITLE:
Planar scintigraphy in assessment of mandibular asymmetry: Unilateral condylar hyperplasia vs asymmetric mandibular hyperplasia
AUTHORS:
Lo John, Yau Yat Yin, Yeung Wai Chow David, Cheung Lim Kwong
KEYWORDS:
cintigraphy; Bone Scan; Facial Asymmetry; Mandibular Asymmetry; Unilateral Condylar Hyperplasia
JOURNAL NAME:
Journal of Biomedical Science and Engineering,
Vol.5 No.12A,
December
31,
2012
ABSTRACT: Objectives:
To 1) explore the planar scintigraphic findings in asymmetry patients caused by
unilateral condylar hyperplasia (UCH) or asymmetric mandibular hyperplasia
(AMH); 2) develop a local agecondylar activity reference norm; and 3) check
the accuracy of the new norm and compare with other analytical methods. Material and Method: Chinese patients with
mandibular asymmetry and scintigraphic findings available were recruited.
Clinical, radiographic records and scintigraphic condylar activity ratio
(CAR) were studied. Regression analysis was performed to quantify the
relationship between age and CAR to develop a new norm. The sensitivity of
condylar activity assessment using a) traditional norm; b) new norm; and c)
percentile difference was compared. In patients with serial data available,
longitudinal analysis of the scintigraphic changes were checked. Result: 109 patients were eligible for
the study. Significant difference in CAR was noted between UCH and AMH
patients. Linear relationship was observed between age and CAR. A new norm of
the age-CAR was established, which showed improved sensitivity in condylar
activity prediction in UCH and AMH when compared with traditional norm.
Relative to percentile difference, the sensitivity of new norm was lower in
AMH but not in UCH patients. Serial analysis revealed gradual decline in CAR
with minimal change in percentile difference. Conclusion and Clinical Relevance: There is difference in scintigraphic
condylar activity between UCH and AMH patients. A norm of age-CAR relationship
was established, which showed improved sensitivity in condylar activity
prediction in UCH patients. Further study is required to confirm the role of
scintigraphy in AMH.