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Successful Treatment Ofanisometropic Amblyopia

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BritishJournalofOphthalmology 1993; 77: 321-322 321 Successful treatment ofanisometropic amblyopia and strabismus following intravitreal silicone oil Br J Ophthalmol: first published as 10.1136/bjo.77.5.321 on 1 May 1993. Downloaded from RR Goble, W A Franks, D Avery, A H Chignell Silicone oil is used in the treatment of complex assessment with Bagolini glasses and Worth's retinal detachments. Its refractive index (1-400- four light test. 1 405) is higher than that ofvitreous (1-336) and Six months postoperatively no manifest devia- can cause a refractive change to high hyper- tion was present and the TNO stereoacuity was metropia in the phakic emmetropic eye.' This 240 seconds of arc. At 1 year full binocular degree of anisometropia can lead to the develop- function had returned with a TNO stereoacuity ment of amblyopia in young children. of60 seconds ofarc and there was a prism fusion A 6-year-old boy developed a traumatic retinal range of 20 dioptres base in and 45 dioptres base detachment successfully treated by vitrectomy out. and intravitreal silicone oil. Postoperative aniso- More than 2 years after the injury the left metropic amblyopia and secondary esotropia visual acuity is 6/6, the lens is clear, and the developed. The amblyopia was successfully retina remains attached. There is no manifest treated with hypermetropic spectacles and occlu- squint and the patient retains full stereoscopic sion. This was followed by oil removal and vision. strabismus surgery. Full stereopsis eventually recovered. Comment Retinal detachments in children are uncommon Case report and are often traumatic in origin. If there is A 6-year-old boy was referred 1 month after associated anterior segment damage and/or blunt trauma to his left eye with an inferior retinal detachment involving the macula then the retinal detachment and a post-equatorial break visual prognosis may be poor. If the macula at 8 o'clock associated with preretinal mem- remains attached and there is no significant brane. The macula was uninvolved and there anterior segment injury then the visual results was no significant anterior segment damage. after surgery should be excellent. Since initial presentation, the left visual acuity Silicone oil is useful in the treatment of eyes had been 6/18 due to vitreous haemorrhage. with complex retinal detachments."4 The long The patient had passed a school eye test the term complications of silicone oil include previous year. A pars plana vitrectomy was glaucoma, cataract, silicone oil emulsification, http://bjo.bmj.com/ performed with peeling of the membrane and, in aphakic eyes, corneal opacification.5-7 surrounding the break. The retinal break was Provided the retina remains attached, silicone judged to be too posterior for scleral buckling oil removal may prevent such problems so internal tamponade with silicone oil was arising. '° used. Children up to 8 years of age may develop Ten days postoperatively, the unaided left amblyopia." The reduction in visual acuity to visual acuity was counting fingers, which 6/18 at presentation and for 1 month before on September 27, 2021 by guest. Protected copyright. improved to 6/60 with + 8 dioptre sphere (cyclo- detachment surgery was caused by the vitreous plegic refraction: 0-00/+050x90 right and haemorrhage from the original injury. However, +8 00/+0 50x 170 left). A left esotropia had also following intravitreal silicone oil injection, the developed, measuring 35 prism dioptres at both uncorrected visual acuity dropped to counting 1/3 m and 6 m with the prism reflection test. Eye fingers and even with the full refractive correc- movements were full with normal saccades. The tion the acuity was only 6/60. It was evident that retina was attached, the fovea appeared normal in the absence of any structural abnormality the on biomicroscopy, and there were no media patient had developed silicone oil induced aniso- opacities. A diagnosis ofamblyopia with second- metropic amblyopia. Department of ary esotropia was made. The amblyopia was The esotropia developed within the first 10 Ophthalmology treated for 1 hour each day with glasses and days after surgery and was secondary to the R R Goble occlusion of the right eye. a of W A Franks anisometropic amblyopia. Following period A H Chignell The left visual acuity improved to 6/18 with loss ofbinocularity, a well controlled phoria may 1 month of treatment, and by 3 months was 6/6. decompensate. This is a possible mechanism in Department of The left esotropia persisted. The silicone oil was this case. The 'blind spot syndrome', in which Orthoptics, St Thomas's Hospital, removed. Forced duction testing and explora- the diplopic image falls on the optic disc of the Lambeth Palace Road, tion of the horizontal recti were normal. A 5 mm deviating eye, may be responsible for the large London SEI 7EH medial rectus recession and a 7 mm lateral rectus angle (35 prism dioptres) ofsquint in this case as D Avery resection were performed. well as the initial absence of diplopia." In some Correspondence to: Mr R R Goble, Department of Two weeks after silicone oil removal, the left trauma cases, fibrosis of the extraocular muscles Ophthalmology, Kent and visual acuity was 6/6 unaided (+0 00/+050x can produce strabismus. In this case the rapidity Canterbury Hospital, Canterbury, Kent CT1 3NG. 170 left). A 10 prism dioptre esotropia at 1/3 m of onset, full movements, and normal muscle Accepted for publication and 6 m persisted. The patient experienced inspection all failed to support this aetiology. 26 January 1993 diplopia and this was confirmed on orthoptic Detachment surgery itself may produce 322 Goble, Franks, Avery, Chignell to this 1 Lean JS. Use of silicone oil as an additional technique in strabismus. The factors which predispose vitreoretinal surgery. In: Ryan SJ, ed. Retina. Glaser BM, include the placement of scleral explants, scieral Michels RG, eds. Surgical retina. St Louis: Mosby, 1989: rectus conjunc- 289-90. dissection beneath muscles, and 2 Cibis PA, Becker B, Okun E, Canaan S. The use of liquid tival scarring, none of which was a factor in this silicone in retinal detachment surgery. Arch Ophthalmol Br J Ophthalmol: first published as 10.1136/bjo.77.5.321 on 1 May 1993. Downloaded from case. 13 1%2; 68: 590-9. 3 Scott JD. The treatment of massive vitreous retraction. Trans Loss of stereopsis occurred during the time Ophthalmol Soc UK 1975; 95: 429-32. eye, as the 4 Lean JS, Leaver PK, Cooling RJ, McLeod D. Management of that silicone oil remained within the complex retinal detachments by vitrectomy and fluid/ high degree of anisometropia produced insuper- silicone oil exchange. Trans Ophthalmol Soc UK 1985; 102: After the oil was removed, a 203-5. able aniseikonia. 5 McCuen B, de Juan E, Landers MB, Machemer R. Silicone oil small esotropia persisted for a few weeks until in vitreoretinal surgery. 2: Results and complications. single vision and eventually full Retina 1985; 5: 198-205. binocular 6 Leaver PK, Garner A, Grey RHB, Hitchings RA. Effects of stereopsis recovered. Unfortunately this intraocular silicone. Trans Ophthalmol Soc UK 1987; 97: 633. recovery may not always occur following 7 Leaver PK, Grey RHB, Garner A. Silicone oil in the treatment transient visual impairment in children, even in of massive preretinal retraction. Late complications in 93 those known previously to have had normal eyes. BrJ Ophthalmol 1979; 63: 361-7. 8 Casswell AG, Gregor ZJ. Silicone oil removal: 1 The effects on binocular single vision.'4 the complications of silicone oil. BrJ Ophthalmol 1987; 71: This case illustrates the importance of testing 893-7. 9 Franks WA, Leaver PK. Removal of silicone oil - rewards and for silicone oil induced anisometropia in young penalties. Eye 1991; 5: 333-7. children. It demonstrates that occlusion com- 10 Gonvers M. Temporary silicone oil tamponade in the manage- ment of retinal detachment with proliferative vitreoretino- bined with the use of hypermetropic spectacles pathy. AmJ Ophthalmol 1985; 100: 239-45. can prevent and treat the associated amblyopia 11 Harwerth RS, Smith EL, Duncan GC, Crawford MLJ, von Noorden GK. Multiple sensitive periods in the development which may compromise the results of otherwise ofthe primate visual system. Science 1986; 232: 235-8. successful detachment surgery. Removal of 12 Swan KC. The blind spot syndrome. Arch Ophthalmol 1948; 40: 371-88. silicone oil should be undertaken as soon as 13 Munoz M, Rosenbaum AL. Long-term strabismus complica- possible to minimise the risk of developing this tions following retinal detachment surgery. J Pediatr Ophthalmol Strabismus 1987; 24: 309-14. as well as its other long term complications. 14 Pratt-Johnson JA, Tillson G. Intractable diplopia after vision restoration in unilateral cataract. Am J Ophthalmol 1989; 107:23-6. http://bjo.bmj.com/ on September 27, 2021 by guest. Protected copyright..
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