PURPOSE. To define the critical period for susceptibility of human stereopsis to an anomalous binocular visual experience. METHODS. Random dot stereoacuity was measured in 152 children with a history of onset of eithe...PURPOSE. To define the critical period for susceptibility of human stereopsis to an anomalous binocular visual experience. METHODS. Random dot stereoacuity was measured in 152 children with a history of onset of either infantile or accommodative strabismus before5 years of age. In each of these populations and in the combined population, the critical periods for susceptibility of stereopsis are described using fourparameter developmental weighting functions. RESULTS. In children with infantile strabismus, the critical period for susceptibility of stereopsis begins at 2.4 months and peaks at4.3 months. In children with accommodative esotropia, the critical period for susceptibility of stereopsis begins at 10.8months and peaks at 20 months. When the data are combined across the two populations, the critical period begins soon after birth and peaks sharply at 3.5 months but shows continued susceptibility to at least4.6 years. CONCLUSIONS. An anomalous binocular visual experience during early infancy severely disrupts stereopsis, yet the critical period for susceptibility of stereopsis extends through late infancy and early childhood and continues to at least 4.6 years of age.展开更多
PURPOSE. Identification of risk factors for accommodative esotropia may help to determine which children with hyperopia may benefit from early spectacle correction or preventive therapy. METHODS. Participants in the f...PURPOSE. Identification of risk factors for accommodative esotropia may help to determine which children with hyperopia may benefit from early spectacle correction or preventive therapy. METHODS. Participants in the family history study were 95 consecutive patients, aged 18 to 60 months, with accommodative esotropia. Participants in the binocular sensory function study were a subgroup of 41 children enrolled in the family history study within 1 month of onset, while the esodeviation was still intermittent. Participants in the hypermetropia study were 345 consecutive patients, ages 12 months to 8 years, with refractive error of + 2.00 D or greater and no esodeviation before age 12 months. RESULTS. In the family history study, 23% of children with accommodative esotropia had an affected first- degree relative, and 91% had at least one affected relative. In the binocular sensory function study, random- dot stereoacuity was abnormal in41% of children, whereas an abnormal motion VEP, Worth4- dot, or positive4- PD base- out prism responses were present in4% or less of the children. In the hypermetropia study, patients with a mean spherical equivalent of<+ 3.00 D and significant anisometropia had a 7.8- fold increased risk for accommodative esotropia over nonanisometropic patients. CONCLUSIONS. A positive family history, subnormal random- dot stereopsis, and hypermetropic anisometropia each pose a significant risk for the development of accommodative esotropia. Assessment of these risk factors in conjunction with refractive screening should help to identify those children who are most likely to benefit from early spectacle correction or preventive treatment.展开更多
To define the prevalence and time course of significant changes in angle of deviation during the first months after the diagnosis of i nfantile esotropia and to determine whether long-term alignment and sensory out co...To define the prevalence and time course of significant changes in angle of deviation during the first months after the diagnosis of i nfantile esotropia and to determine whether long-term alignment and sensory out comes differ when surgical alignment is performed on infants with stable vs unst able angles of deviation. Prospective cohort study. setting: Institutional and c linical practice. patient population: Newly diagnosed patients with infantile es otropia (N=208). observation procedure: Preoperative measurements of the angle o f deviation on the initial visit and at approximate six-week intervals until su rgery was performed. main outcome measures: Ocular alignment at six weeks, one y ear, and four years postoperative and stereoacuity at age five to nine years. Ov erall, 57%of infants had an esodeviation on the second visit that was within 10 prism diopters (p.d.) of the deviation measured on the initial visit (stable gr oup), 33%had an increase of 10 p.d. or more (unstable group), and 11%had a dec rease of 10 p.d. or more. Among the 127 patients with additional preoperative vi sits, many switched between the stable and unstable categories during follow-up . Long-term, stable and unstable preoperative alignment groups had similar post operative motor alignment, re-operation rates, rates of prescription of hyperop ic, or bifocal spectacle correction and stereoacuity. It may not be necessary to wait for a “stable”angle of esodeviation before surgery since both alignment and sensory outcomes were similar for stable and unstable groups.展开更多
文摘PURPOSE. To define the critical period for susceptibility of human stereopsis to an anomalous binocular visual experience. METHODS. Random dot stereoacuity was measured in 152 children with a history of onset of either infantile or accommodative strabismus before5 years of age. In each of these populations and in the combined population, the critical periods for susceptibility of stereopsis are described using fourparameter developmental weighting functions. RESULTS. In children with infantile strabismus, the critical period for susceptibility of stereopsis begins at 2.4 months and peaks at4.3 months. In children with accommodative esotropia, the critical period for susceptibility of stereopsis begins at 10.8months and peaks at 20 months. When the data are combined across the two populations, the critical period begins soon after birth and peaks sharply at 3.5 months but shows continued susceptibility to at least4.6 years. CONCLUSIONS. An anomalous binocular visual experience during early infancy severely disrupts stereopsis, yet the critical period for susceptibility of stereopsis extends through late infancy and early childhood and continues to at least 4.6 years of age.
文摘PURPOSE. Identification of risk factors for accommodative esotropia may help to determine which children with hyperopia may benefit from early spectacle correction or preventive therapy. METHODS. Participants in the family history study were 95 consecutive patients, aged 18 to 60 months, with accommodative esotropia. Participants in the binocular sensory function study were a subgroup of 41 children enrolled in the family history study within 1 month of onset, while the esodeviation was still intermittent. Participants in the hypermetropia study were 345 consecutive patients, ages 12 months to 8 years, with refractive error of + 2.00 D or greater and no esodeviation before age 12 months. RESULTS. In the family history study, 23% of children with accommodative esotropia had an affected first- degree relative, and 91% had at least one affected relative. In the binocular sensory function study, random- dot stereoacuity was abnormal in41% of children, whereas an abnormal motion VEP, Worth4- dot, or positive4- PD base- out prism responses were present in4% or less of the children. In the hypermetropia study, patients with a mean spherical equivalent of<+ 3.00 D and significant anisometropia had a 7.8- fold increased risk for accommodative esotropia over nonanisometropic patients. CONCLUSIONS. A positive family history, subnormal random- dot stereopsis, and hypermetropic anisometropia each pose a significant risk for the development of accommodative esotropia. Assessment of these risk factors in conjunction with refractive screening should help to identify those children who are most likely to benefit from early spectacle correction or preventive treatment.
文摘To define the prevalence and time course of significant changes in angle of deviation during the first months after the diagnosis of i nfantile esotropia and to determine whether long-term alignment and sensory out comes differ when surgical alignment is performed on infants with stable vs unst able angles of deviation. Prospective cohort study. setting: Institutional and c linical practice. patient population: Newly diagnosed patients with infantile es otropia (N=208). observation procedure: Preoperative measurements of the angle o f deviation on the initial visit and at approximate six-week intervals until su rgery was performed. main outcome measures: Ocular alignment at six weeks, one y ear, and four years postoperative and stereoacuity at age five to nine years. Ov erall, 57%of infants had an esodeviation on the second visit that was within 10 prism diopters (p.d.) of the deviation measured on the initial visit (stable gr oup), 33%had an increase of 10 p.d. or more (unstable group), and 11%had a dec rease of 10 p.d. or more. Among the 127 patients with additional preoperative vi sits, many switched between the stable and unstable categories during follow-up . Long-term, stable and unstable preoperative alignment groups had similar post operative motor alignment, re-operation rates, rates of prescription of hyperop ic, or bifocal spectacle correction and stereoacuity. It may not be necessary to wait for a “stable”angle of esodeviation before surgery since both alignment and sensory outcomes were similar for stable and unstable groups.
