RESUMO
Multifocal and toric intraocular lenses (IOLs) or the so-called premium IOLs are currently widely used in adult patients as a one-step refractive solution following cataract surgery. However, the decision to implant a premium IOL in a pediatric patient involves multiple factors affecting the child's visual development and is associated with several dilemmas and surgical challenges. The purpose of this review is to summarize these factors and analyse the influence of each of them on the visual outcomes following premium IOL implantation. A review of literature was conducted using the relevant keywords from various databases until 31st January 2022. All pertinent studies with multifocal or toric IOL implantation in children were reviewed, and relevant articles were studied in detail for age, IOL power calculation, visual outcomes (refractive outcomes, contrast sensitivity and stereopsis) and complications such as dysphotic phenomena and others. A total of 17 relevant studies (10 case series/interventional studies and 7 case reports) on the subject were included. All studies showed a favourable refractive outcome; however, the data available was significantly less. Studies with earlier models of multifocal IOLs showed a higher incidence of IOL decentration and posterior capsule opacification; however, more recent studies with newer IOL models showed much better safety profiles. Toric IOLs showed promising results in all the studies evaluated. Premium IOLs have shown promising results in the pediatric age group. However, their long-term outcomes specifically concerning refractive shift, capsular contraction and role in the management of amblyopia needs to be explored further.
Assuntos
Astigmatismo , Extração de Catarata , Lentes Intraoculares , Lentes Intraoculares Multifocais , Facoemulsificação , Adulto , Humanos , Criança , Implante de Lente Intraocular/métodos , Acuidade Visual , Refração Ocular , Astigmatismo/cirurgia , Facoemulsificação/métodosRESUMO
The long-standing nativist vs. empiricist debate asks a foundational question in epistemology - does our knowledge arise through experience or is it available innately? Studies that probe the sensitivity of newborns and patients recovering from congenital blindness are central in informing this dialogue. One of the most robust sensitivities our visual system possesses is to 'biological motion' - the movement patterns of humans and other vertebrates. Various biological motion perception skills (such as distinguishing between movement of human and non-human animals, or between upright and inverted human movement) become evident within the first months of life. The mechanisms of acquiring these capabilities, and specifically the contribution of visual experience to their development, are still under debate. We had the opportunity to directly examine the role of visual experience in biological motion perception, by testing what level of sensitivity is present immediately upon onset of sight following years of congenital visual deprivation. Two congenitally blind patients who underwent sight-restorative cataract-removal surgery late in life (at the ages of 7 and 20 years) were tested before and after sight restoration. The patients were shown displays of walking humans, pigeons, and cats, and asked to describe what they saw. Visual recognition of movement patterns emerged immediately upon eye-opening following surgery, when the patients spontaneously began to identify human, but not animal, biological motion. This recognition ability was evident contemporaneously for upright and inverted human displays. These findings suggest that visual recognition of human motion patterns may not critically depend on visual experience, as it was evident upon first exposure to un-obstructed sight in patients with very limited prior visual exposure, and furthermore, was not limited to the typical (upright) orientation of humans in real-life settings.
Assuntos
Percepção de Movimento , Animais , Cegueira , Humanos , Recém-Nascido , Movimento (Física) , Transtornos da Visão , Visão OcularRESUMO
A 15-year-old male patient presented with vision loss after blunt trauma to the right eye and with clinical evidence of posterior lenticonus. The posttraumatic lenticonus was eccentric (superotemporal). Irregular astigmatism with high myopia on dilated retinoscopy within the lenticonus, localized posterior convexity of peripheral capsule on ultrasound biomicroscopy, and increased higher-order aberrations (HOAs) on wavefront aberrometry compared with fellow-eye findings confirmed the diagnosis. To our knowledge, acquired peripheral posterior lenticonus representing dialysis of Weigert ligament after acute blunt trauma is a new finding. This case provides an insight into the pattern of higher HOAs associated with any type of lenticonus.