Refractive errors, strabismus and ocular findings in children with different types of spinal muscular atrophy

To investigate the ophthalmic characteristics of patients with spinal muscular atrophy (SMA).

Clinical and refractive features of genetically confirmed SMA patients were assessed retrospectively. Three groups were established based on disease type, excluding patients with concurrent eye disease or those with unreliable measurements due to systemic conditions.

The study enrolled patients with SMA type 1 (n = 18), SMA type 2 (n = 16), and SMA type 3 (n = 14). Gender distribution showed nine males and nine females in type 1, ten males and six females in type 2, and ten males and four females in type 3, with no significant difference (p = 0.456). Average ages were 2.67 ± 1.03 for type 1, 6.69 ± 3.72 for type 2, and 11.21 ± 5.48 for type 3. SMA Type 1 exhibited a higher hyperopia frequency than the other groups (p = 0.009), while SMA type 2 had a higher myopia prevalence (p = 0.007). No significant differences were found in astigmatism distributions (p = 0.887 and p = 0.778). Best-corrected visual acuity was comparable between type 2 and type 3 (p = 0.304). One type 1 patient had esotropia, and one type 2 patient had exotropia. Three SMA type 1 patients had optic atrophy, and no patients exhibited associated retinal findings.

Individuals with SMA may encounter refractive issues, strabismus, and optic atrophy. Patients' refractive conditions seem to differ based on the disease type, potentially linked to the illness's pathophysiology and age group. Comprehensive research with larger sample sizes and control groups is essential for a more profound understanding.