case_images: PMC7784631_01
case_images: Optical coherence tomography of the right (OD) and left (OS) eye from patient 1 showing an increase in retinal nerve fiber layer thickness in all quadrants (white arrows) and uniformly increased values of peripapillary retinal nerve fiber layer thickness.
case_images: fgene-11-585136-g001.jpg
case_images: PMC7784631_01_fgene-11-585136-g001.jpg
case_images: F1
case_images: Optical coherence tomography (OCT) revealed increased thickness of retinal nerve fiber layers (Figure 1).
case_images: Patient 1 brain MRI revealing the characteristic ARSACS findings. MRI of the index patient reveals atrophy of the superior cerebellar vermis (arrowhead) and thinning of the posterior midbody of corpus callosum (white arrow) (A, T1); bilateral parietal atrophy, mostly prominent on the left side (white arrows) (B, T1); bilateral hypointense stripes in pons (arrowheads) (C, T2; D, FLAIR); bilateral hyperintensity of lateral pons (stars) on coronal images (E, T2); and a hyperintense rim around both thalami (white arrows) (F, T2).
case_images: fgene-11-585136-g002.jpg
case_images: PMC7784631_01_fgene-11-585136-g002.jpg
case_images: F2
case_images: Brain magnetic resonance imaging (MRI) depicted atrophy of the superior cerebellar vermis, thinning of the posterior mid-body of corpus callosum, bilateral parietal atrophy on T1-weighted images, bilateral hypointense stripes in the pons on T2/fluid-attenuated inversion recovery (FLAIR) sequences, bilateral hyperintensity of the lateral pons on coronal images on T2 sequences, and a hyperintense rim around both thalami on T2-weighted images (Figure 2).
case_images: PMC7784631_02
case_images: Family pedigree and sequence chromatograms. The two affected siblings (patient 1: II.1, patient 2: II.3) were homozygous for the identified SACS variant (c.429_430delTT), and both parents were heterozygous carriers.
case_images: fgene-11-585136-g003.jpg
case_images: PMC7784631_02_fgene-11-585136-g003.jpg
case_images: F3
case_images: Afterward, segregation analysis using Sanger sequencing was performed, which confirmed that her affected brother was homozygous for the identified mutation, and both parents were heterozygous carriers (Figure 3).