Age and disease both have an impact on the size of the structures in the anterior visual pathway (AVP). When assessing the likelihood of pathology, normative data can be helpful. Magnetic resonance (MR) imaging planes are not respected by AVP structures. The purpose of this research was to use multiplanar reformation (MPR) of high-resolution 3D T2-weighted fast spin echo (3D T2w FSE) images to provide normative age-related and axis-corrected data of the AVP structures. High-resolution 3D T2w FSE images were adjusted to the axis of each AVP structure, and 32 measurements were taken for each patient in 145 children with normal brain MRI scans (ages 2 months to 18 years). Age-specific descriptive statistics were computed, and the efficacy of several growth models was evaluated in order to develop a formal statistical model that permits extrapolation beyond the sample. A reference table of descriptive data and prediction plots for age, height, and body surface area (BSA) were generated using the best overall performing statistical model, which also accounted for field strength (1.5 vs. 3T). The transverse diameter of the globe, the maximum diameter of the retrobulbar nerve sheath, the intracranial segment of the optic nerve, and the transverse diameter of the chiasm were shown to have the highest intraclass correlation coefficient values ranging from 0.474 to 0.967. There was no significant age-related change in the maximal retrobulbar diameter of the optic nerve sheath or the lateral superoinferior diameter of the chiasm. Axis-corrected data from the MPR of high-resolution 3D T2w FSE images were used to generate detailed charts of reference values for AVP structures, as well as prediction plots in relation to age, height, and BSA. Additional material includes an Excel worksheet that can be used to determine standard deviations for the 9 most important AVP structures.

Source: bmcpediatr.biomedcentral.com/articles/10.1186/s12887-022-03637-z