Three-dimensional periorbital asymmetry assessment of congenital microphthalmia children with a structured light 3D scanning system

Determining Asymmetry Thresholds in Anophthalmia/Microphthalmia Using a Three-dimensional Animated Model

PURPOSE

Congenital microphthalmia and anophthalmia are rare development disorders with underdevelopment of the orbital region, resulting in asymmetry of the face. No clear guidelines exist to determine when these deviations are acceptable.

METHODS

The face of a healthy 6-year-old child was three-dimensionally scanned. On this scan, we modeled various incremental degrees of facial asymmetries using three-dimensional modeling software. We modeled for smaller palpebral fissures, sunken eyes, and downward displacement of the eye. We also tested whether adjusting the vertical palpebral fissure height in relation to the horizontal palpebral fissure width affected perception. A total of 22 videos were created in which the model turned the head horizontally and vertically. We created a questionnaire asking raters how acceptable the face is, on a linear scale from 0 to 10.

RESULTS

Results showed a correlation between the degree of asymmetry and the acceptability score of the raters. Enophthalmos of ≥6 mm, palpebral fissure width ≤79% compared with the other eye, and 2 mm or more downward displacement of the eye resulted in a significant different acceptability score. The desire for correction was strongly increased when these thresholds were exceeded. Adjusting the vertical palpebral fissure height to the horizontal palpebral fissure width resulted in a worse acceptability score.

CONCLUSION

A unilateral sunken eye (enophthalmos) of 6 mm or more, asymmetric horizontal palpebral fissure length of ≤79%, and a lower position of one eye of more than 2 mm resulted in unacceptable judgment. These data can be used to evaluate treatment outcome in children treated for congenital microphthalmia and anophthalmia.

Correlation Between the Computed Tomography and 3D Scanning System-Based Periorbital Morphology of Children with Congenital Microphthalmia

PURPOSE

This article aimed to explore the correlation between the periorbital morphology determined using a 3D scanning system and CT in congenital microphthalmia.

METHODS

Fifty-two children with microphthalmia aged 0-6 were enrolled in this study. All the participants were subjected to orbital CT scans and 3D scanning. The CT and 3D scanning images were separately processed to obtain the orbital and facial parameters. Multivariate regression was used to analyze the correlation between 3D parameters and orbital volume.

RESULTS

The orbital volume of the affected side (15.25 ± 3.35 cm3) was generally smaller than the unaffected side (18.58 ± 2.65 cm3, p < .001). Based on CT, at all ages, the parameters of the unaffected orbit were greater than the affected side. In the 3D scanning and 3D reconstruction based on CT, both unaffected and affected sides were highly correlated. A multiple linear regression equation including three 3D scanning factors was obtained for the orbital volume (R2 = 0.808, p < .001).

CONCLUSIONS

The retarded orbital volume could be estimated by the parameters based on 3D scanning, along with axial length. In the follow-up stage, 3D scanning can be a novel alternative method to assess the degree of orbital growth retardation in congenital microphthalmia.

The Repeatability and Reproducibility of a New Minimally Invasive Method for Orbital Pressure Measurement

BACKGROUND

Evaluation of orbital pressure is crucial for monitoring various orbital disorders. However, there is currently no reliable technique to accurately measure direct orbital pressure (DOP). This study aimed to establish a new method for the DOP as well as to verify its repeatability and reproducibility in rabbits.

METHODS

The study included 30 normal eyes from fifteen 3-month-old New Zealand white rabbits. After administering inhalation anesthesia, intraocular pressure (IOP) was determined by tonometry (Tonopen). For DOP manometry, a TSD104 pressure transducer was inserted between the disposable injection needle and the syringe, and the output results were displayed on a computer. Two observers independently participated in the experiment to verify its repeatability and reproducibility.

RESULTS

The mean IOP of rabbits was significantly higher than the DOP in normal rabbits (11.67 ± 1.08 mm Hg versus 4.91 ± 0.86 mm Hg, P < 0.001). No significant interocular difference was detected for both IOP and DOP ( P > 0.05). A high correlation was found for intraobserver measurements of both IOP (intraclass correlation coefficient = 0.87, P < 0.001) and DOP (intraclass correlation coefficient = 0.89, P < 0.001). A high agreement was also presented for the interobserver reproducibility for the measurements of IOP [Pearson correlation coefficient ( R ) = 0.86, P < 0.001] and DOP ( R = 0.87, P < 0.001). Direct orbital pressure was positively correlated with IOP in both observers ( R 1 = 0.66, R 2 = 0.62, P < 0.001). The Bland-Altman plots revealed that 5.0% (3/60) of the IOP and DOP measurement points were outside of the 95% limits of agreement, respectively.

CONCLUSIONS

The TSD104 pressure transducer-based manometry may serve as a reliable device for the measurement of DOP, providing real-time measuring results with acceptable reproducibility and repeatability.

An overview of three-dimensional imaging devices in dentistry

OBJECTIVE

To review four types of three-dimensional imaging devices: intraoral scanners, extraoral scanners, cone-beam computed tomography (CBCT), and facial scanners, in terms of their development, technologies, advantages, disadvantages, accuracy, influencing factors, and applications in dentistry.

METHODS

PubMed (National Library of Medicine) and Google Scholar databases were searched. Additionally, the scanner manufacturers' websites were accessed to obtain relevant data. Four authors independently selected the articles, books, and websites. To exclude duplicates and scrutinize the data, they were uploaded to Mendeley Data. In total, 135 articles, two books, and 17 websites were included.

RESULTS

Research and clinical practice have shown that oral and facial scanners and CBCT can be used widely in various areas of dentistry with high accuracy.

CONCLUSION

Although further advancement of these devices is desirable, there is no doubt that digital technology represents the future of dentistry. Furthermore, the combined use of different devices may bring dentistry into a new era. These four devices will play a significant role in clinical utility with high accuracy. The combined use of these devices should be explored further.

CLINICAL SIGNIFICANCE

The four devices will play a significant role in clinical use with high accuracy. The combined use of these devices should be explored further.