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Paper text:
choroidal neovascularization ( cnv ) is a common cause of vision loss in pathological myopia.1 the pathogenesis of cnv in pathological myopia is still unclear but is postulated to result from axial elongation of the globe causing distension of the posterior segment with greater ocular volume than in the normal eye .
later on , the formation of lacquer cracks leads to cnv.1 the most appropriate treatment for myopic cnv has not yet been established and the choices are limited.2 antivascular endothelial growth factor seems to offer a new modality for management of pathological myopia .
we report a case of myopic cnv that showed improvement after a single injection of ranibizumab .
a 45-year - old chinese man , who was a known case of high myopia with a spherical equivalent refractive error of 5.0 diopter ( d ) , presented with sudden onset painless reduced vision of his right eye of 2 weeks duration .
there was no metamorphopsia , and there was no relationship with headache , jaw claudication , or double vision .
he had undergone bilateral cataract surgery 10 years before presentation , and had a good visual outcome postoperatively with glasses .
his right vision on presentation was 6/30 which was not improved with pinhole and 6/6 for the left eye .
the anterior segments revealed a clear cornea bilaterally , and a deep anterior chamber with intraocular pressures of 14 mmhg ( right eye ) and 16 mmhg ( left eye ) .
the right fundus showed chorioretinal atrophy at the posterior pole , with a subretinal hemorrhage at the inferotemporal fovea ( figure 1 ) .
the macula of the left eye showed myopic maculopathy with a chorioretinal atrophy appearance and without subretinal hemorrhage .
fundus fluorescein angiography of the right eye revealed a hyperfluorescent area at the fovea which was increasing in intensity and size ( figure 2 ) .
an intravitreal injection of ranibizumab 0.05 ml ( lucentis , novartis , basel , switzerland ) was given to the right eye .
the patient was treated with moxifloxacin ophthalmic solution 0.5% ( alcon , alcon laboratories inc , fort worth , tx ) at 4-hourly intervals for 3 days following the procedure .
after 1 week of intravitreal ranibizumab injections , visual acuity improved to 6/15 with pinhole .
the intraocular pressure was normal , and no complications , such as intraocular infection , retinal tear , or vitreous hemorrhage was seen .
the fundus showed that the subretinal hemorrhage had become less dense and was reducing in size ( figure 3 ) . at 10-week follow - up ,
visual acuity improved to 6/7.5 with glasses , and repeat fundus fluorescein angiography showed the absence of cnv ( figure 4 ) .
follow - up at 6 months showed that visual acuity had normalized to 6/6 with glasses , which was maintained up to 12 months after treatment .
by definition , pathological myopia is also known as high , degenerative , or malignant myopia which is characterized as excessive elongation of axial length from 25.5 to 26.5 mm and refractive errors of at least 5.0 or 7.5 d.2 the risk factors for development of pathological myopia depend on ethnicity and genetics , whereas increased intraocular pressure and retinal degeneration , such as lacquer cracks and patchy atrophy , are risk factors for developing cnv secondary to pathological myopia . the prevalence is higher in asian populations , whereas six autosomal dominant loci and one x - linked recessive locus have been reported for pathological myopia.2 in this case , the patient s spherical equivalent refractive error was 5.0 d which is one of the risk factors for developing cnv secondary to myopia .
several treatments have been proposed to treat myopic cnv , including laser photocoagulation,2,3 surgical removal of cnv,4,5 macular translocation,4,6 and photodynamic therapy with and without intravitreal triamcinolone acetonide,1,7,8 but the most appropriate treatment has not yet been established .
laser photocoagulation seemed to cause more harm than no treatment in an early study , but subsequent studies showed more efficacy in preventing irreversible visual loss .
laser photocoagulation should be considered in extrafoveal cases compared with juxtafoveal due to long - term expansion of laser scar causing decrease in visual acuity.2 photodynamic therapy with verteporfin is the other treatment option for subfoveal cnv in pathological myopia . in one study ,
a group treated with photodynamic therapy had more stable visual acuity compared with a placebo group.1 there are two main surgical procedures for cnv pathological myopia , ie , macular translocation and surgical removal .
hamelin et al compared these surgical procedures , but no significant difference was found in postoperative best corrected visual acuity .
however , recurrence of cnv was more common after surgical removal and the incidence of retinal detachment was similar in both groups.4 recent reports have suggested that antivascular endothelial growth factor could be a new modality for the management of pathological myopia.913 ranibizumab has been found to be effective in the treatment of exudative age - related macular degeneration.14 cnv due to pathological myopia is not associated with significant retinal edema , so the retinal barriers might be less disturbed in comparison with age - related macular degeneration , and thus a possible higher penetration ability of the small ranibizumab molecule might be a significant advantage.11 table 1 summarizes seven reported studies and one case report of intravitreal ranibizumab for myopic cnv in the literature from 2008 to 2011.11,1521 based on these studies , intravitreal ranibizumab appears to be effective for the treatment of myopic cnv , resulting in functional and anatomic improvements . a study done by lai et al19 and a case report by kumaran et al18 showed that a single injection of intravitreal ranibizumab is effective for the treatment of myopic choroidal neovascularization as was presented in this patient .
the number of intravitreal ranibizumab injections required depends on patient characteristics , including location of myopic cnv and prior treatment.15 in conclusion , a single injection of ranibizumab showed improvement in this patient with myopic cnv .
we report a case of myopic choroidal neovascularization that showed improvement after a single injection of ranibizumab . a 45-year - old chinese man with high myopia presented with sudden onset painless central scotoma of his right eye of 2 weeks duration . 
 there was no history of trauma . 
 his right eye vision on presentation was 6/30 which showed no improvement with pinhole . 
 the right fundus showed myopic maculopathy at the posterior pole with subretinal hemorrhage at the inferotemporal fovea . 
 the optic disc was tilted with inferotemporal peripapillary atrophy . 
 there was a myopic maculopathy appearance in the macula of the left eye . 
 fundus fluorescein angiography revealed choroidal neovascularization at the fovea of the right eye . 
 a diagnosis of right eye choroidal neovascularization secondary to myopic maculopathy was made . 
 a single intravitreal injection of ranibizumab 0.05 ml was given . 
 ten weeks following intravitreal injection , vision had improved to 6/7.5 , and repeated fundus fluorescein angiography showed absence of choroidal neovascularization . 
 follow - up at 6 months showed visual acuity had normalized to 6/6 with glasses , which was maintained up to 12 months following treatment . 
 the right fundus showed no further subretinal hemorrhage with no new lesions .