Good Visual Acuity (good + visual_acuity)

Distribution by Scientific Domains


Selected Abstracts


Long-term outcome of children with cortical visual impairment

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 6 2006
Carey A Matsuba MDCM MHSc FRCP(C)
Cortical visual impairment (CVI) is now the most common cause of visual impairment in children. Little is known about the long-term visual outcome. This study evaluates the outcome of children with congenital CVI. Using medical records, 423 children (225 males, 198 females) were identified with congenital CVI. Of these children, 259 had follow-up visual acuity assessments. The children's gestational age varied with 32 weeks or less representing 15.9%; 33 to 36 weeks representing 10.7%; 37 to 42 weeks representing 61.2%; and 43 weeks or greater representing 0.9% (11.3% of patients'gestational age was unrecorded). Clinical data were extracted and information regarding outcome was gathered. The majority of children showed improvement in their visual acuity levels after 2 or more years of follow-up. For the 194 children initially assessed before 3 years of age, 97 had improved, 75 were unchanged, 18 had deteriorated, and 4 had sub-optimal assessments. For the 74 children initially assessed at 3 or more years of age, 23 had improved, 44 remained unchanged, 3 had deteriorated, and 4 had sub-optimal testing. Children with better visual acuity levels at follow-up were more likely to have favourable cognitive outcomes (non-mental retardation)* in 12.2% versus 2.8% (p<0.01). Similarly, favourable motor outcomes (independent ambulation) were present in 20.1% for those with better visual acuities versus 7.9% for those with poorer visual acuities (p<0.01). Our study demonstrates that the majority of children with CVI underwent improvement in visual acuity. Additional disabilities were common, but those children with better visual acuity outcomes faired better. Given the frequency of comorbid conditions, appropriate diagnostic assessment services are needed. [source]


The absence of lateral congruency between sighting dominance and the eye with better visual acuity

OPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 1 2007
Jonathan S. Pointer
Abstract The notion that in subjects with normal binocular vision (i.e. non-strabismic cases) the eye showing sighting dominance will also most likely be that individual's better-sighted eye has proved to be persistent. A review and analysis of the literature has now demonstrated, across several population groups, the fallacy of this belief. In fact, the occurrence of lateral congruency between sighting dominance and the eye with better visual acuity is at a statistical level no greater than chance would predict. Some clinical implications of this outcome are considered. [source]


Prognosis for splicing factor PRPF8 retinitis pigmentosa, novel mutations and correlation between human and yeast phenotypes,

HUMAN MUTATION, Issue 5 2010
Katherine V. Towns
Abstract PRPF8 -retinitis pigmentosa is said to be severe but there has been no overview of phenotype across different mutations. We screened RP patients for PRPF8 mutations and identified three new missense mutations, including the first documented mutation outside exon 42 and the first de novo mutation. This brings the known RP-causing mutations in PRPF8 to nineteen. We then collated clinical data from new and published cases to determine an accurate prognosis for PRPF8 -RP. Clinical data for 75 PRPF8 -RP patients were compared, revealing that while the effect on peripheral retinal function is severe, patients generally retain good visual acuity in at least one eye until the fifth or sixth decade. We also noted that prognosis for PRPF8 -RP differs with different mutations, with p.H2309P or p.H2309R having a worse prognosis than p.R2310K. This correlates with the observed difference in growth defect severity in yeast lines carrying the equivalent mutations, though such correlation remains tentative given the limited number of mutations for which information is available. The yeast phenotype is caused by lack of mature spliceosomes in the nucleus, leading to reduced RNA splicing function. Correlation between yeast and human phenotypes suggests that splicing factor RP may also result from an underlying splicing deficit. © 2010 Wiley-Liss, Inc. [source]


Corneal oedema after cataract surgery: predisposing factors and corneal graft outcome

ACTA OPHTHALMOLOGICA, Issue 2 2009
Margareta Claesson
Abstract. Purpose:, Pseudophakic bullous keratopathy (PBK) is one of the main indications for corneal transplantation. Graft survival and visual outcome in this group are often poorer than for other indications. The aim of this study was to find risk factors for developing corneal oedema after cataract surgery and factors that influence the subsequent survival of the graft and the visual outcome. Methods:, We carried out an observational, retrospective cohort study using data from the Swedish Cornea Transplant Register and patient medical records. A total of 273 patients whose indication for corneal transplantation was corneal oedema after cataract surgery were included in the study. Multiple logistic regression analysis and, where appropriate, univariate analyses were applied. Results:, A total of 43% of the patients developed persistent corneal oedema immediately after cataract surgery, the main risk factors for which were phacoemulsification and pre-existing endothelial disease. Almost a third (32%) of the transplants for PBK failed within 2 years, for which rejection and other postoperative complications increased the risk. Half (50%) the patients had visual acuity , 0.1 at 2 years after keratoplasty. Comorbidity, increasing duration of the bullous keratopathy and increasing age affected the visual outcome negatively. Conclusions:, Phacoemulsification was a risk factor for immediate persistent corneal oedema after cataract surgery, although it did not increase the overall risk of developing PBK. However, transplants for immediate PBK had a better survival rate than those for later onset PBK. Shorter duration of PBK and intraocular lens exchange at the time of penetrating keratoplasty increased the likelihood of good visual acuity. [source]


Sequential development of bilateral primary choroidal melanoma

ACTA OPHTHALMOLOGICA, Issue 4 2000
Hayyam Kiratli
ABSTRACT. Purpose: A case of a woman who had bilateral choroidal melanoma diagnosed sequentially 20 months apart and managed conservatively is described. Methods: The first eye having a juxtapapillary melanoma was treated with a notched episcleral radioactive plaque. The second eye, initially containing a small nevus with unequivocal rapid growth, was managed with diode laser transpupillary thermotherapy. Results: Both tumors regressed considerably following treatment and the patient retained good visual acuity in both eyes. No other malignancies or metastasis were detected during the follow-up period. Conclusions: A small choroidal nevus rapidly grew after treating a choroidal melanoma in the fellow eye. Close follow-up of such patients is mandatory. Also, conservative treatment should be opted whenever possible given the unpredictable course of the opposite melanocytic lesion. [source]