Types of choroidal neovascularisation in newly diagnosed exudative age-related macular degeneration

Abstract

Aim: To describe the types and location of choroidal neovascularisation (CNV) in exudative age-related macular degeneration (AMD), including vascularised pigment epithelial detatchments (PED), and most recently described subtypes, such as retinal choroidal anasmostosis, also termed ''retinal angiomatous proliferation'' (RAP). Methods: Prospective multicentre consecutive descriptive case series. A total of 207 consecutive cases of newly diagnosed exudative AMD undergoing fluorescein angiography (FA) were recruited by 7 French referral hospital-based or private centres. Indocyanine green angiography (ICG) also was performed, when judged necessary by investigators. Types and location of CNV were classified by two independent experts and adjudicated by a third when discordant. Results: All patients had FA, while ICG was performed in 50% of subjects. A total of 17.6% had classic CNV only, 5.4% and 8.3% had predominantly and minimally classic CNV, respectively. Occult CNV could be classified in occult CNV without PED (32.7%) and occult CNV with PED, ie, vascularised PED (23.9%). RAP was observed in 15.1% of cases, and accounted for 30% of vascularised PED. In 5.8% of the cases there was haemorrhagic AMD and 4.8% had fibrovascular scars. Lesions were mainly subfoveal (80%). Agreement between the centre's ophthalmologist and the final validated expert classification was moderate (k = 0.52 for location and 0.59 for type of lesion). Conclusion: This study confirms that newly diagnosed cases of exudative AMD are mainly occult and subfoveal. RAP appeared as a common lesion in patients with newly diagnosed exudative AMD.A ged-related macular degeneration (AMD) is the leading cause of blindness in industrialised countries, representing 50% of all blindness cases.1 It is currently the third most common cause of blindness worldwide, behind cataract and glaucoma.1 More than 80% of severe visual loss in AMD is due to choroidal neovascularisation (CNV) and its consequences: exudation, bleeding and disciform scarring.2 At the time of completion of the present study, the only approved treatments for exudative AMD in France were laser photocoagulation and verteporfin photodynamic therapy (PDT). The choice of treatment with these laser-based therapies depended on the location, composition and size of the lesion. Fluorescein angiography has been used to define lesion size and composition. It allows distinction between well demarcated classic CNV, and ill-defined occult CNV. This angiographic distinction is of major importance for the choice of treatment; laser photocoagulation being preferred in cases of extrafoveal or juxtafoveal classic CNV, while PDT was preferred in cases of subfoveal predominantly classic and occult only CNV.3-5 The location and exact boundaries of occult CNV often are difficult to determine precisely on fluorescein angiography due to obscuration of the neovascular membrane by overlying turbid exudates, blood and/or pigment, and rapid fluorescein pooling beneath a serous PED. As the vast majority of CNV at diagnos...

Long-term visual outcomes of intravitreal ranibizumab treatment for wet age-related macular degeneration and effect on blindness rates in south-east Scotland

“…8 The proportion of different types of angiographically identified lesions were similar in this study to other reported studies for populations showing occult lesions as the most common form identified angiographically for patients with wet AMD. 9,10 Cohen et al 9 found a total of 17.6% had classic CNV only, 5.4% and 8.3% had predominantly and minimally classic CNV, respectively, and 32.7% had occult CNV. RAP was observed in 15.1% of cases.…”

Ranibizumab for retinal angiomatous proliferation in age-related macular degeneration

“…3,14,15 This peculiar form of AMD is characterized by a high and cumulative risk of bilateralization, estimated to be as high as 40% after 1 year, 56% after 2 years, and 100% after 3 years. 16 ICG, by improving the imaging of choroidal circulation, is an invaluable diagnostic tool in such cases, showing typically a late focal area of intense hyperfluorescence described as a hot spot.…”

Serous pigment epithelial detachment in age-related macular degeneration: comparison of different treatments

“…Acute visual loss can be caused by tears of the RPE layer, especially in combination with massive subretinal haemorrhages. 2,[11][12][13]28,29 Using ICG-A, different kinds of neovascularization could be identified that can be regarded as being responsible for serous PED. Occult CNV situated mostly at the margin can often be distinguished from centrally localized CNV on a RAP lesion.…”

“…This process can be accelerated by ruptures in the retinal pigment epithelium (RPE) layer and by subretinal haemorrhages. [7][8][9][10][11][12][13] Previously used therapeutic strategies such as photocoagulation or photodynamic therapy (PDT) have produced only unsatisfactory results. [13][14][15][16][17] The reasons for this include both the development of PED and CNV recurrences.…”