Related Experiment Videos
Hypothesis: myopia of prematurity is caused by postnatal bone mineral deficiency
1Department of Paediatrics, University of Ulm, Germany.
Insights
Bone mineral deficiency in preterm infants may cause skull deformation, leading to myopia. Supplementation with calcium and phosphorus reduced myopia prevalence in very low birth weight infants.
Area of Science:
- Ophthalmology
- Neonatology
- Pediatrics
Background:
- Myopia is common in preterm infants, often associated with retinopathy of prematurity (ROP).
- The cause of myopia in preterm infants without ROP remains unclear.
- Skull shape and bone mineral status are potential contributing factors.
Purpose of the Study:
- To investigate the hypothesis that skull deformation due to bone mineral deficiency causes myopia in preterm infants.
- To assess the effect of calcium and phosphorus supplementation on myopia development in very low birth weight infants.
Main Methods:
- Historical comparison of two groups of very low birth weight infants.
- One group received calcium and phosphorus supplementation to prevent bone mineral deficiency; the other did not.
- Data collected via questionnaires and refraction measurements.
Main Results:
- Significantly lower spectacle need in supplemented infants (11%) compared to unsupplemented (61%).
- Lower incidence of myopia (refraction > -1.00 D) in supplemented infants (2/22) versus unsupplemented (5/14).
- Supplementation showed a statistically significant protective effect (P < 0.05).
Conclusions:
- Postnatal skull deformation, driven by bone mineral deficiency, is a plausible cause of myopia in preterm infants.
- Calcium and phosphorus supplementation may prevent or reduce myopia in very low birth weight infants.
- Further research is warranted to confirm these findings and explore preventative strategies.
Abstract:
Myopia is a frequent finding in preterm children. The close association between myopia and retinopathy of prematurity (ROP) suggested a causal relationship, but myopia of prematurity without ROP has yet to be explained. An alternative explanation is presented: myopia is caused by postnatal ellipsoid deformation of the spheric eyeball, i.e. excessive elongation of the optical, as a result of a dolichocephalic deformation of the skull with a short frontal axis. This deformation of the skull is the direct result of bone mineral deficiency frequently observed in very low birth weight infants with increasing postnatal age. This hypothesis is supported by the results of a historical comparison of very low birth weight infants without and with supplementation with calcium and phosphorus that was given in order to prevent postnatal bone mineral deficiency. In the unsupplemented group 4 of 23 children (61%) needed spectacles but only 6 out of 55 (11%) children who were supplemented as babies (questionnaire). Refraction measurements showed myopia stronger than -1 o.d. in group 1 in 5 of 14 infants, whereas in group 2 only 2 out of 22 infants were myopic (P < 0.05).