Are collimated low-dose digital radiographs valid for performing Delaire's architectural analysis?

Cephalometric analyses for cleft patients: a statistical approach to compare the variables of Delaire's craniofacial analysis to Bergen analysis

Objectives

Cephalometric analyses using lateral craniofacial radiographs are common diagnostic procedures for evaluating skeletal patterns. However, in patients with pronounced abnormalities like cleft lip and palate, standard cephalometric analyses and landmarks may not be suitable. This study aims to clarify whether the inclusion of landmarks less compromised by the cleft defect or located outside the cleft area results in a different cephalometric assessment of the viscerocranium. Delaire’s whole-skull analysis and Bergen analysis were examined for similarities and underlying common observations.

Materials/methods

Based on the cephalometric evaluation of 217 patients with different types of non-syndromal cleft formation, Delaire and Bergen analysis were compared using three statistical methods: correlation analysis, factor analysis, and cluster analysis. Reproducibility was assessed by Bland–Altman plots, intraclass correlation coefficients, mean absolute differences, and coefficients of variability.

Results

Although Delaire analysis and Bergen analysis are based on different concepts and landmarks, a majority of corresponding variables was found. Certain aspects of craniofacial base relation and craniospinal articulation are only assessed by Delaire analysis. All but one variable showed very good reproducibility.

Conclusions

The inclusion of landmarks less compromised by or located outside the cleft area does not result in variables that provide a different assessment of the viscerocranial area.

Clinical Relevance

The findings contradict the concept of invalidity of landmarks compromised by the cleft defect or located within the affected cleft area. Within the scope of its viscerocranial field of view, Bergen analysis appears to be on a par with Delaire analysis in the diagnosis of cleft patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00784-021-04006-3.

The influence of lead thyroid collars on cephalometric landmark identification

OBJECTIVE

To investigate whether the application of thyroid collars (TCs) affects cephalometric landmark identification.

STUDY DESIGN

A randomized and observer-blinded diagnostic study with head films taken from 2 groups was undertaken, with 1 group wearing TCs during radiography (n = 100) and 1 group not wearing TCs (n = 100). The interobserver reproducibility of 15 landmarks was evaluated using 1-way analysis of variance and independent samples t test to compare the groups.

RESULTS

The total mean error radius of the non-TC group (1.28 +/- 1.47 mm) was smaller (P < or = .001) than that of the TC group (1.57 +/- 1.58 mm). Three landmarks located on the hyoid bone and on the second and third cervical vertebrae were identified as the main confounding factors.

CONCLUSIONS

Personal lead shielding of the thyroid gland affects landmark identification, but the overall clinical effect is negligible. Thyroid collars should be routinely applied during cephalometric radiography if cephalometric analyses are limited to structures above the second cervical vertebra.