Infrared Light Structured Sensor Three-dimensional Approach to Estimate Kidney Volume: A Validation Study

Using a Smartphone 3-Dimensional Surface Imaging Technique to Manufacture Custom 3-Dimensional-Printed Eyeglasses

Importance

Finding a suitable fit in glasses for pediatric patients with congenital and acquired craniofacial abnormalities is difficult; consequently, these children are at high risk of vision loss secondary to refractive amblyopia as they often have poor adherence to daily glasses wearing. Custom 3-dimensional (3D)-printed glasses may have an improved design and fit, but access is limited by the availability of computed tomography and magnetic resonance imaging (MRI).

Objective

To describe a method for using a commercially available smartphone 3D surface imaging (3DSI) technique to capture facial anatomy as a basis for custom glasses design.

Design, Setting, and Participants

This quality improvement study analyzes data from a case series in a primary academic center with multiple referral centers throughout the United States. The evaluation included reported fit descriptions from patients with poor glasses adherence due to craniofacial abnormalities.

Main Outcomes and Measures

Key anatomic parameters for glasses fit (face width, distance from ear bridge to nasal bridge, distance from center of pupil to center of nasal bridge, distance from lateral to medial canthus, ear vertical offset, and nasal bridge width) were compared between scans. A 3DSI scan was considered successful if these key parameters could be determined and the difference in measurements was less than 5% between MRI and 3DSI. A second outcome measure included the fit of glasses designed by the 3DSI method as reported by the patient, parent, or guardian.

Results

Measurements of key parameters for glasses fit were similar across MRI and 3DSI scans with a mean (SD) difference of 1.47 (0.79) mm between parameters (range, 0.3-4.60 mm). Among 20 patients aged 1 to 17 years with craniofacial abnormalities, all achieved a successful fit (reporting daily glasses adherence without irritation) as judged by the patient, parent, or guardian. A mean of 1.7 revisions were made from initial prototype to final frame production using 3DSI technology.

Conclusions and Relevance

This study demonstrated that smartphone-enabled 3DSI coupled with widely available 3D printing technology can produce custom frames with a successful fit for patients with craniofacial anomalies. This accessible and well-tolerated imaging process may have implications for adherence with glasses wearing among patients at risk of vision loss due to amblyopia.