Inflammatory choroidal neovascular membrane in posterior uveitis-pathogenesis and treatment

Abstract

Choroidal neovascular membrane (CNVM) formation is a well-documented sight-threatening complication of posterior segment intraocular inflammation (PSII). The aim of this article is to review the basic and clinical science literature on the pathogenesis of CNVM formation in PSII and to present results of a case series. We searched the literature using the mesh terms- inflammation, CNVM, age-related macular degeneration, immunosuppression, photodynamic therapy, steroids, vascular endothelial growth factors and posterior uveitis. Additionally, we evaluated the visual outcome of and clinical response to our standard treatment protocol involving a combination treatment for young patients with inflammatory CNVM. The development of CNVM in PSII is promulgated by infiltrating myeloid cells as well as choroidal and retinal myeloid cell activation, subsequent vascular endothelial growth factors, cytokine and chemokine production and complement activation acting in consort to mediate angiogenic responses. No clear standard of care currently exists for the treatment of inflammatory CNVM and various combinations have been tried. Using our combination treatment, visual acuity improved in four, stabilized in one and worsened in four patients. Though significant advances have occurred in the understanding of the pathogenesis and management of this condition, optimizing therapeutic regimens will require further well-constructed prospective cohort series.

Figure 1

Algorithm for treatment used in the study (choroidal neovascular membrane; photodynamic therapy; intravitreal triamcinolone 4 mg/0.1 ml; mycophenolate mofetil 1 g po BD; fundus fluorescein angiography; subretinal fluid; visual acuity; intravenous methylprednisolone)

Figure 2

Complement pathway

Figure 3

Patient with idiopathic panuveitis with peripapillary choroidal neovascular membrane [initial fundus photograph showing swollen optic nerve head with inferior subretinal hemorrhage (a), fundus fluorescein angiography two weeks after intravenous methylprednisolone and commencement of mycophenolate mofetil (b), fundus fluorescein angiography on the day of photodynamic therapy shows only a small area of active choroidal neovascular membrane temporal to the optic disc, fundus photograph at 13 months shows peripapillary atrophy and fibrosis (b)]