Evaluation of Micronucleus and Associated Abnormalities in Buccal Cells Post CT Scan Exposure- An Observational Study

Abstract

Introduction: Dental diagnostic radiation is reported to cause significant damage in buccal cells while, the same effects due to Computed Tomography (CT) scans have not been routinely cited in literature. The buccal cells were studied in patients exposed to CT scans for evaluating the cells with micronuclei, associated nuclear abnormalities and changes in Proliferative Index (PI) of cells. The obtained head and neck CT scans i.e., CT for brain and facial bone, CT paranasal sinuses and CT cervical spine were compared in terms of the micronuclear counts. Aim: To estimate the counts of micronucleus associated nuclear abnormalities and changes in PI in patients before and after head and neck CT scans. Materials and Methods: An observational study, wherein 40 patients undergoing CT scans for head and neck region, were selected by consecutive systematic sampling. Buccal smears were made before and 10 days after CT scan. Papanicolaou (PAP) staining and micronuclear analysis were performed as per Tolbert’s criteria. The obtained cell counts were compared for differences before and after scans by paired t-tests. Results: Significant differences (p<0.05; paired t-test) were noted between pre and post exposure values for head and neck CT scans in terms of Micronucleus (MN) counts, Binulceated cells (BN), Nuclear buds (NBUDs) and Multinucleated Micronucleus (MMN) cells. The post exposure radiation induced cell PI was found to be 6.0, a 3 fold rise from normal value of 2.0. Conclusion: CT scans taken for head and neck region caused changes related to DNA damage and genotoxicity in buccal mucosal cells. Comparatively, CT cervical spine have showed more nuclear abnormalities than CT for brain and facial bone and CT paranasal sinuses. The associated micronuclear cells have contributed to rise in PI.

Keywords

• bi-nucleated cells
• dna damage
• genotoxicity
• nuclear buds
• proliferative index