Intraocular lenses in children: changes in axial length, corneal curvature, and refraction. (1/105)

AIM: To assess changes in axial length, corneal curvature, and refraction in paediatric pseudophakia. METHODS: 35 eyes of 24 patients with congenital or developmental lens opacities underwent extracapsular cataract extraction and posterior chamber intraocular lens implantation. Serial measurements were made of axial length, corneal curvature, objective refraction, and visual acuity. RESULTS: For patients with congenital cataracts (onset < 1 year age) the mean age at surgery was 24 weeks. Over the mean follow up period of 2.7 years, the mean increase in axial length of 3.41 mm was not significantly different from the value of an expected mean growth of 3.44 mm (paired t test, p = 0.97) after correction for gestational age. In the developmental cataract group (onset > 1 year of age) the mean age at surgery was 6.4 years with a mean follow up of 2.86 years. This group showed a mean growth in axial length of 0.36 mm that was not significantly different from an expected value of 0.47 mm (paired t test, p = 0.63). The mean preoperative keratometry was 47.78 D in the congenital group and 44.35 D in the developmental group. At final follow up the mean keratometry in the congenital group was 46.15 D and in the developmental group it was 43.63 D. In eyes followed for at least 2 years, there was an observed myopic shift by 24 months postoperatively of 3.26 D in the congenital cases (n = 10) and 0.96 D in the developmental cases (n = 18). CONCLUSION: The pattern of axial elongation and corneal flattening was similar in the congenital and developmental groups to that observed in normal eyes. No significant retardation or acceleration of axial growth was found in the eyes implanted with IOLs compared with normal eyes. A myopic shift was seen particularly in eyes operated on at 4-8 weeks of age and it is recommended that these eyes are made 6 D hypermetropic initially with the residual refractive error being corrected with spectacles.  (+info)

Diabetic versus non-diabetic colour vision after cataract surgery. (2/105)

AIMS: To examine whether the colour vision abnormalities found in phakic patients with diabetes mellitus is preserved after removal of the lens by cataract surgery. METHODS: 21 diabetic (16 IDDM and five NIDDM) and 19 non-diabetic patients of comparable age, postoperative visual acuity, and sex distribution, all aphakic or pseudophakic following cataract surgery, had their monocular colour vision examined using the Farnsworth-Munsell 100 hue test. The fundus status of the diabetic patients ranged from no retinopathy to photocoagulation treated proliferative diabetic retinopathy. Patients with macular oedema were specifically excluded from the study. RESULTS: The error scores of both the diabetic (mean 146 (SD 94)) and the non-diabetic patients (83 (79)) did not deviate significantly from the age related normal range. The error score in the diabetic group was significantly higher than in the non-diabetic group (p=0.02) but the amplitude of the difference was small in comparison with previous studies of phakic subjects. The error scores in the diabetic group were not correlated with the degree of retinopathy (p>0.2). CONCLUSION: After cataract surgery only a minor difference exists between the colour vision scores of diabetic and non-diabetic patients. This indicates that accelerated yellowing of the lens in diabetes is the predominant cause of the colour vision anomaly found in phakic diabetic patients.  (+info)

Retroillumination versus reflected-light images in the photographic assessment of posterior capsule opacification. (3/105)

PURPOSE: To investigate the relative merit of retroillumination and of reflected light slit-lamp-derived photographs in the assessment of the opacification of the posterior lens capsule. METHODS: Retroillumination and slit-lamp-derived reflected-light photographs were taken on 23 consecutive eyes with posterior capsule opacification (PCO) in uncomplicated pseudophakia. Subjective grading was performed on both types of photographs to evaluate the extent and density of posterior capsular opacification. Best-corrected visual acuity (BCVA) before and after YAG laser capsulotomy was used to assess the impact of capsular opacification on visual function. RESULTS: After capsulotomy all patients attained a BCVA > or = 46 letters (> or =20/32) with a mean increase of 25 letters, indicating that PCO was the cause of visual impairment in these patients. The relative capacity of retroillumination and of reflected-light photographs to adequately capture the extent and the severity of posterior capsule opacification varied considerably. Reflected-light images, in addition to frequently producing higher severity scores for the opacity than retroillumination photographs, in 4 of 23 eyes (17.4%) proved to be the only technique able to document the presence of PCO. CONCLUSIONS: Our results indicate that, with respect to retroillumination images, reflected-light photography has an increased ability to adequately capture the presence and the severity of PCO and that the use of only retroillumination images may lead to its underestimation. This may be relevant to clinical studies aiming to evaluate incidence and progression of this condition.  (+info)

Is pseudophakic astigmatism a desirable goal? (4/105)

PURPOSE: To determine whether pseudophakic astigmatism is a desirable goal, and if so, which one is better: against-the-rule (ATR) or with-the-rule (WTR). METHOD: Eyes were included only if they had an uncorrected vision > or = 6/18 and N/18. Three groups, of 40 patients each were evaluated: group 1, pseudophakes with neutral astigmatism; group 2, with ATR and group 3, with WTR astigmatism Unaided distance and near visual acuity was recorded. Statistical analysis was performed using the chi-square test for independence. RESULTS: Unaided distance vision of > or = 6/7.5 was achieved in 19 eyes (47.5%) of group 1 (neutral), 12 eyes (30%) in group 2 (ATR), and 5 eyes (12.5%) in group 3 (WTR) (p = 0.0133, significant). Unaided near vision of > or = N/9 was achieved in 17 eyes (42.5%) in group 1 (neutral), 34 eyes (85%) in group 2 (ATR), and 10 eyes (25%) in group 3 (WTR) (P < 0.001, significant). Group 1 (neutral) fared the best for unaided distance visual acuity. Group 2 (ATR) was better than in group 3 (WTR) for distant vision. Group 2 (ATR) fared the best for unaided near vision. CONCLUSION: ATR astigmatism could be a desirable goal after cataract extraction in selected populations because the largest proportion of these cases achieved good unaided near vision with acceptable distant vision.  (+info)

Phakic-pseudophakic bullous keratopathy following implantation of a posterior chamber IOL in the anterior chamber to correct hypermetropia. (5/105)

There is an increasing demand for refractive surgery stemming from a heightened awareness among patients wearing spectacles or contact lenses. Cosmetic or occupational reasons prompt patients to seek the alternative option of refractive surgery.  (+info)

Primary rhegmatogenous retinal detachment: 20 years of change. (6/105)

AIM: To compare characteristics, management, and outcome of two groups of patients with primary rhegmatogenous retinal detachment (RRD) presenting to the same vitreoretinal unit approximately 20 years apart. METHODS: 124 patients in 1979-80 and 126 cases in 1999 were compared. RESULTS: More cases were pseudophakic and fewer aphakic in 1999 than 1979-80. More cases of giant retinal tear and fewer dialyses were operated on in 1999. Vitrectomy was a primary procedure in 63% of cases in 1999 but only 1% in 1979-80. Anatomical success rates were statistically similar: 79.8% primary and 88.8% final success in 1979-80, and 84% primary and 93.6% final success in 1999. CONCLUSION: Surgical management of primary RRD has changed greatly in 20 years. Success rates have changed little, despite availability of differing surgical techniques.  (+info)

The shape of the aging human lens: curvature, equivalent refractive index and the lens paradox. (7/105)

Scheimpflug slit images of the crystalline lens are distorted due to the refracting properties of the cornea and because they are obliquely viewed. We measured the aspheric curvature of the lens of 102 subjects ranging in age between 16 and 65 years and applied correction for these distortions. The procedure was validated by measuring an artificial eye and pseudophakic patients with intraocular lenses of known dimensions. Compared to previous studies using Scheimpflug photography, the decrease of the radius of the anterior lens surface with age was smaller, and the absolute value for the radius of the anterior and posterior lens surface was significantly smaller. A slight decrease of the posterior lens radius with age could be demonstrated. Generally, front and back surfaces were hyperbolic. Axial length was measured of 42 subjects enabling calculation of the equivalent refractive index of the lens, which showed a small, but highly significant decrease with age. These new findings explain the lens paradox and may serve as a basis for modelling the refractive properties of the lens.  (+info)

Cataract in leprosy patients: cataract surgical coverage, barriers to acceptance of surgery, and outcome of surgery in a population based survey in Korea. (8/105)

BACKGROUND/AIMS: Cataract is the leading cause of blindness in leprosy patients. There is no population based information on the cataract surgical coverage, barriers to use of surgical services, and outcome of surgery in these patients. We sought to determine these measures of cataract programme effectiveness in a cured leprosy population in South Korea. METHODS: The population consisted of residents of six leprosy resettlement villages in central South Korea. All residents were invited to participate in a study of eye disease and interviewed regarding use of surgical services and reasons for not using these services. RESULTS: The cataract surgical coverage in this population was 55.4% when <6/18 was used as the cut off and increased to 78.3% when the cut off was <6/60. Barriers reported by patients included being told by the doctor that the cataract was not mature and a perception by the patient that there was no need for surgery. Among patients who had aphakic surgery, 71% were still blind in the operative eye while among patients who had pseudophakic surgery, 14% were still blind (presenting vision). Blindness in pseudophakic patients could be reduced to 3% with spectacle correction. CONCLUSION: Cataract prevalence in leprosy patients will increase as life expectancy continues to increase. Leprosy control programmes will need to develop activities aimed at reducing the burden of cataract. Recommendations include establishing collaborative agreements with ophthalmological services to provide high quality IOL surgery to these patients, training of health staff to identify and refer patients in need of surgery, monitoring the uptake of cataract surgery among patients needing services, and monitoring the outcome of surgery to improve refractive outcome.  (+info)

• 1
• 2
• 3
• 4
• 5
• 6
• 7
• 8
• 9
• 10