Nicholas P. Strong

Vitreous loss in planned extracapsular cataract extraction does lead to a poorer visual outcome

Forty-six cases of vitreous loss during planned extracapsular cataract extraction salvaged by anterior vitrectomy and primary anterior chamber lens implantation were compared in a retrospective cohort study with 92 individually matched controls. The postoperative visual outcome for cases with vitreous loss was significantly poorer than that for controls even after adjustment for confounding variables. Part of this visual morbidity was explained by cystoid macular oedema and retinal detachment, but even after adjusting for these two complications visual outcome remained worse among cases than controls. There was a significantly higher incidence of clinically apparent cystoid macular oedema amongst cases compared with controls (20% versus 1%). Two retinal detachments occurred among the cases but this difference in incidence was not statistically significant.

Risk factors for strabismus in children born before 32 weeks’ gestation

AIM To investigate risk factors associated with strabismus in children born prematurely. METHODS Prospective study of all children born before 32 weeks’ gestation between 1 January 1990 and 31 December 1991 in a geographically defined population of approximately 3 million in the Northern Region of the United Kingdom. All children were examined aged 2 years by the same ophthalmologist and paediatrician. RESULTS 558 children (98.6% of study group) were examined. Logistic regression showed an increased risk of strabismus in children with cicatricial retinopathy of prematurity (p=0.02), refractive error (p=0.003), family history of strabismus (p<0.0001), and poor neurodevelopmental outcome (p<0.0001), in particular impaired locomotor skills (p=0.008) and hand-eye coordination (p=0.001). Gestational age and regressed acute ROP were not independent risk factors for strabismus (p=0.92 and 0.85 respectively). CONCLUSIONS This study has identified factors which are independently related to strabismus (although not necessarily causative) and others which are related only indirectly. This may contribute both to the management of children born prematurely and to future studies of the aetiology of strabismus.

The use of the Newcastle Control Score in the management of intermittent exotropia

Aim: To evaluate the use of the Newcastle Control Score (NCS) in the management of intermittent exotropia (X(T)). Participants and methods: Children aged <11 years with X(T) had an assessment of NCS as part of routine management. Other data collected included visual acuity, near and distance alignment with alternating prism cover test and near (Frisby test) and distance stereoacuity (Frisby Davis Distance Stereotest (FD2TM)). Analysis involved correlation between baseline NCS, angle and stereoacuity, examination of change over time and logistic regression to determine predictors of surgery. Results: Baseline data were obtained on 272 children and follow-up data on 157. Mean (SD) age was 4 (1.9) years. Complete NCSs were obtained for all except one child at baseline, and all children at follow-up. At baseline, total NCS and the home control component were correlated with near stereo (r = –0.22, p<0.01 and r = –0.19, p<0.02, respectively), near alignment (r = 0.34, p<0.001 and r = 0.19, p<0.02) and distance alignment (r = 0.30, p<0.001 and r = 0.26, p<0.001). The clinic near control component was correlated with near alignment (r = 0.39, p<0.001), but not near stereoacuity, and the clinic distance control with near alignment (r = 0.16, p<0.02), distance alignment (r = 0.27, p<0.001) and distance stereoacuity (r = –0.25, p<0.03). A high (poor) NCS (⩾4) at the latest follow-up predicted surgery (p<0.001, OR 29.3, 95% CI 6.2 to 138.7). Conclusion: The NCS is a useful measure of the clinical severity of X(T), can be used to serially assess improvement or deterioration and is a useful tool for the management of these patients.

Refractive errors in children born before 32 weeks gestation

Purpose: To document the refractive errors in a cohort of children born before 32 weeks gestation.Methods: All children born before 32 weeks gestation between 1 January 1990 and 31 December 1991 to mothers resident in the Northern Region of the National Health Service were examined at 2 years old (n = 558).Results: Stage 3 or worse retinopathy of prematurity (ROP) was associated with myopia. In those not developing stage 3 or worse ROP, the refractive errors were myopia in 1.5%, hypermetropia >4 dioptres (D) in 5.4%, anisometropia >1 D in 1.1% and astigmatism >1.25 D in 5.7%.Conclusion: The incidence of refractive errors in those not developing stage 3 or worse ROP was similar to that in the general population.

PRIMARY OCULAR RELAPSE IN ACUTE LYMPHOBLASTIC LEUKAEMIA

Relapse of acute lymphoblastic leukaemia (ALL) occurred in the anterior segment of four children. All cases had been treated according to the Medical Research Councils UK Acute Lymphoblastic Leukaemia trial protocol (UKALL) including 2 years of continuation chemotherapy. In three cases the diagnosis was confirmed by anterior chamber aspirate while in one case the diagnosis was presumed on clinical grounds alone. All four cases experienced isolated leukaemic relapse in the anterior segment within 2 months of stopping therapy. The months immediately following cessation of continuation chemotherapy as part of the UKALL regime appear to represent a ‘high-risk’ period for primary anterior segment relapse of ALL. Children with ALL presenting with uveitis should be regarded as having leukaemic relapse and anterior chamber taps with or without an iris biopsy should be considered to confirm this diagnosis. Early diagnosis and treatment of ocular leukaemic relapse is likely to give these children the best chance of ultimate cure.

Factors related to the incidence of secondary haemorrhage in 462 patients with traumatic hyphaema

In a retrospective study of 462 in-patients with traumatic hyphaema, secondary haemorrhage occurred in 8.7% of patients. A multivariate analysis demonstrated that the size of hyphaema on presentation and the presence of retinal damage did not affect the probability of secondary haemorrhage. The incidence of secondary haemorrhage was found to decrease by approximately half with the use of topical steroid (p = 0.005), but did not appear to be influenced by the use of cycloplegics. These data indicate in an unselected sequential population of patients, the therapeutic importance of topical steroid in the treatment of blunt ocular trauma.

Factors related to the final visual outcome of 425 patients with traumatic hyphaema

A retrospective study of the visual outcome of 425 in-patients with traumatic hyphaema has been conducted. A multivariate analysis demonstrated that after adjusting for age, sex and pre-existing poor vision, the size of hyphaema on presentation and the presence of retinal damage were significant predictors of a worse final visual outcome (p=0.00003 and 0.00001 respectively). Topical steroid and/or cycloplegic medication, and the occurrence of secondary haemorrhage did not influence the final visual outcome after adjustment for the other variables. These data illustrate, in an unselected sequential population of patients, the role of these factors in terms of final visual outcome following hyphaema from blunt ocular trauma.