Comparing the Use of Smartphone and Vernier Calipers for Corneal Diameter Measurement in Nigerian Term Neonates

Abstract

Background: Corneal diameter (CD) measurement in newborns is essential for the detection of blinding ocular pathologies. It requires  specially trained personnel, contact techniques, and the use of anesthesia. Smartphone use may obviate these challenges.

Aim: This  study compares CD measurement among newborns using a Smartphone and manual calipers.

Subjects and Methods: This is a cross- sectional comparative study done at Alex Ekwueme Federal University Teaching Hospital, Abakaliki, Nigeria. Consecutively selected stable term neonates whose mothers consented to the study and met the inclusion criteria had their CDs measured with both calipers and  smartphones and the values compared. Mean, range, and standard deviation were calculated using Statistical Package for the Social  Sciences (SPSS) IBM (version 22), while paired t‑test calculated the difference in mean CD measurements between both methods. Pearson’s correlation and Bland–Altman’s analysis determined the correlation and agreement between both methods, respectively. Inter  and intraobserver repeatability were assessed. A P value less than 0.05 was taken as statistically significant. 

Results: The mean CD  measurement using calliper method was 10.01 ± 0.29mm and 10.03 ± 0.24 mm right eye (RE) and left eyes (LE), respectively) for  investigator 1 and 10.16 ± 0.25 mm and 10.19 ± 0.21 mm (RE, LE) for investigator 2. Using smartphone measurement, mean CD  measurements of 9.98 ± 0.21 mm and 10.00 ± 0.29 mm (RE, LE) were observed for investigator 1 and 10.07 ± 0.19 mm and 10.06 ± 0.21  mm (RE, LE) for investigator 2. The difference in mean CD for both instruments and by both investigators was not statistically significant  (P value > 0.05). 

Conclusion: Corneal diameter measurement in neonates using smartphone technology does not deviate significantly  from caliper measurement; it is safe, easy to use, and advocated.