Purpose <p>Adolescent myopia is a growing global concern. This study sought to compare the effects of orthokeratology lenses (OKL) and peripheral defocus spectacles (PDS) on myopia progression and axial elongation, based on assessments obtained from multispectral refractive topography (MRT).</p> Background <p>Peripheral hyperopic defocus has been implicated in myopia development. While OKL and PDS are both used to address this issue, their comparative effectiveness and regional defocus patterns remain unclear.</p> Methods <p>This retrospective study included 75 children and adolescents aged 6–15 years, divided into OKL (<i>n</i> = 50) and PDS (<i>n</i> = 25) groups. MRT was used to assess relative peripheral retinal defocus using the retinal deviation value (RDV), while spherical equivalent (SE) and axial length (AL) were assessed at baseline and after 6 months.</p> Results <p>The OKL group showed stronger myopic defocus in the total retinal deviation value (TRDV) and RDV-45&#xa0;(retinal deviation value within&#xa0;0 and 45°), whereas both groups exhibited hyperopic defocus in RDV-N (nasal), with a greater magnitude in the PDS group. After 6 months, the OKL group had significant axial elongation (mean ΔAL = 0.07 mm, <i>p</i> &lt; 0.001), while AL changes in the PDS group were not significant (<i>p</i> = 0.24). Direct comparison revealed that axial elongation was significantly greater in the OKL group than in the PDS group (<i>p</i> = 0.01). In addition, SE changes in the PDS group were significant (<i>p</i> &lt; 0.001), suggesting optical influence without corresponding axial growth.</p> Conclusion <p>Although OKL induced stronger peripheral myopic defocus in several regions, axial elongation over 6 months was smaller in the PDS group. These findings suggest that PDS may help inhibit axial elongation in some children and that MRT offers a useful tool for assessing peripheral refraction and supporting individualised myopia-control strategies.</p>