Recently, intravitreal bevacizumab (Avastin) injection has gained popularity as a potential treatment for choroidal neovascularization (CNV) associated with age related macular degeneration and pathologic myopia. The injection is utilized, either as a sole treatment or combined with photodynamic therapy (PDT) using verteporfin.
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2 Although there is no definitive information on longterm safety for either intravitreal bevacizumab or combined treatment, these therapies are considered safe and have no known serious ocular or systemic adverse events.
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Herein, we present a patient with myopic CNV, who developed retinal detachment with a macular hole following combined PDT and intravitreal bevacizumab injection.
Case Report
A 58-year-old woman was diagnosed with CNV secondary to pathologic myopia in her right eye (right eye = -17 D, left eye = -15 D) (
Fig. 1). The best corrected visual acuity in the affected eye as measured with a Snellen chart was 20/200. After an informed discussion of available therapies, the patient received combined PDT and 1.25 mg intravitreal bevacizumab injection. Four weeks after the initial treatment, the patient received a second intravitreal bevacizumab injection. Both treatments were uneventful.
A week after receiving the second injection, the patient presented with worsening vision in her right eye. Her visual acuity was counting fingers at 1 m. Examination revealed retinal detachment involving the posterior pole with a macular hole. Ocular coherence tomography (OCT) confirmed the presence of a macular hole (
Fig. 2).
The patient underwent standard three-port pars plana vitrectomy with internal limiting membrane peeling, fluid-air exchange and silicone oil injection. During the operation, peripheral fundus examination was performed with scleral indentation, and no additional peripheral hole was observed. On follow-up one week later, the macula had flattened and visual acuity was 20/400.
Discussion
The development of retinal detachment with a macular hole may occur as a spontaneous process in highly myopic eyes.
4 However, the retinal detachment with a macular hole in our patient occurred shortly after PDT and repeated injections of intravitreal bevacizumab. Therefore, the time course suggests the treatment had a potentially causal role.
Several possible mechanisms may have induced the development of retinal detachment with a macular hole. The intravitreal injection may have induced vitreous incarceration at the needle insertion site, causing vitreoretinal traction leading to development of a macular hole and subsequent retinal detachment.
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7 We performed a combined treatment, and there has been a report of macular hole development several weeks after PDT treatment using verteporfin. Thus, PDT may have induced the development of the macular hole.
8 Lastly, bevacizumab itself may have caused the macular hole by modulating the permeability and activity of the CNV and inducing contraction of the vascular membrane, leading to exacerbation of tangential traction on the overlying retina.
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11 The short duration in the onset of retinal detachment with a macular hole after the second injection of intravitreal bevacizumab also suggests a possible causal role of the drug.
In conclusion, PDT and intravitreal bevacizumab injection in the treatment of myopic CNV can be associated with retinal detachment with a macular hole. Patients need to be informed about this potential complication, and a higher index of suspicion may be warranted in patients who report sudden vision loss after the treatment.