Measurement of corneal thickness, optic nerve sheath diameter and retinal nerve fiber layer as potential new non-invasive methods in assessing a risk of cerebral edema in type 1 diabetes in children.

AIMS: Some patients with diabetic ketoacidosis develop cerebral edema (CE) in the course of type 1 diabetes mellitus (T1D), which may result in central nervous system disorders and high mortality. The imperfection of existing neuroimaging techniques for early recognition of CE forces us to search for the new and non-invasive methods. The aim of the study was to assess the usefulness of new methods (pachymetry, transorbital ultrasonography-USG, optical coherence tomography-OCT study) in the assessment of the risk of CE occurrence in children with newly diagnosed T1D.

METHODS

The study group included 50 children with newly diagnosed T1D, 54 patients with long-term T1D as a reference group and 40 children without glucose tolerance disorders as controls. In all subjects, a corneal thickness (CCT) index with pachymeter, optic nerve sheath diameter (ONSD) using transorbital USG and retinal nerve fiber layer (RNFL) during OCT study were measured and compared with selected clinical parameters of T1D.

RESULTS

In patients from a study group at onset of T1D, the higher CCT (p < 0.001) and ONSD (p < 0.001) values were observed as compared to the results obtained after 48 h of metabolic compensation. The ONSD correlated negatively with pH value (r = - 0.64; p < 0.001), BE (r = - 0.54, p < 0.001) and HCO3- (r = - 0.50; p < 0.001). A positive correlation between RNFL and Na+ levels (r = 0.47; p < 0.005) was also observed.

CONCLUSIONS

Transorbital USG and pachymetry may serve as the potential promising methods for the non-invasive assessment of the increased risk of development of CE in patients with T1D.