Purpose: The aim of this study was to compare the one-year efficacy of three spectacle lens designs, highly aspherical lenslets (HALs), horizontally asymmetric peripheral defocus (HAPD) lenses, and standard single vision lenses (SVLs) in slowing myopia progression in school-aged children. Methods: In this prospective, non-randomized study, 57 children, aged 8–17 years, were grouped based on the type of lenses worn: HAL (n = 16), HAPD (n = 21), or SVL (n = 20). Comprehensive ophthalmologic examinations were performed at baseline, 6 months, and 12 months. Outcome measures included spherical equivalent refraction (SER), spherical refraction (SR), cylindrical refraction (CR), and axial length (AL). Data were analyzed using non-parametric tests with significance set at p < 0.05. Results: All groups showed some progression in SER and AL over 12 months. The HAL group demonstrated the smallest median SER change (−0.3 D), compared to HAPD (−0.5 D) and SVL (−0.4 D), though group differences were not statistically significant (p = 0.111). Axial elongation was significantly lower in the HAL group (0.1 mm, IQR: 0.0–0.2 mm) compared to HAPD and SVL (both 0.2 mm, p < 0.0001). CR remained stable in all groups, with no clinically meaningful changes. The HAPD groups showed no advantages over SVL in any parameter. Conclusions: Among the three lens types studied, HAL lenses were the most effective in reducing both refractive and axial myopia progression over 12 months. These findings support their use as a reliable intervention in pediatric myopia control.

Background: Arachnoid cysts are typically benign and asymptomatic, but large cysts can exert a mass effect on adjacent neural structures. Based on the available literature, no cases of cortical visual impairment (CVI) in an adolescent caused by posterior fossa arachnoid cysts have been reported. Case presentation: We report the case of a previously healthy 16-year-old girl who presented with sudden and rapidly progressive bilateral visual loss due to a large retrocerebellar arachnoid cyst. She reported blurred vision, tunnel vision-like, and decreased visual acuity. Although neuro-ophthalmologic and imaging workup revealed no damage to the anterior visual pathways, she exhibited progressive visual decline. Functional tests confirmed bilateral cortical visual impairment: pattern-reversal visual evoked potentials (VEPs) showed preserved and symmetric P100 latencies and amplitudes, while automated perimetry revealed bilateral concentric visual field constriction with preserved central islands. Following cystoperitoneal drainage, her vision rapidly and completely recovered. Conclusions: To the best of our knowledge, this is the first reported case of reversible CVI in an adolescent caused by a posterior fossa arachnoid cyst without intracranial pressure (ICP) elevation or optic nerve involvement, and with tunnel vision-like. Our findings emphasize the role of posterior fossa lesions in visual dysfunction and highlight the potential reversibility of cortical visual loss when timely decompression is achieved. This case underscores the importance of including posterior fossa lesions in the differential diagnosis of unexplained bilateral visual loss, even in the absence of elevated intracranial pressure or anterior visual pathway involvement.