IDIOPATHIC POLYPOIDAL CHOROIDAL VASCULOPATHY

Signs and Symptoms

Idiopathic polypoidal choroidal vasculopathy (IPCV), historically known as posterior uveal bleeding syndrome, is a typically unilateral disease that produces numerous periodic bouts of retinal pigment epithelium (RPE) detachment with or without hemorrhage secondary to serosanguinous leakage in the peripapillary region.1-13 A macular variant has been identified.5-7 The disease has also been associated with the risk factor of smoking, myopic degeneration with the presence of staphyloma, and tilted disc syndrome.7,9,14

Though frequently mistaken for age-related macular degeneration (AMD), its differentiation is based on age of onset (younger individuals), race (often non-white), lack of drusen, as well as its characteristic angiographic and optical coherence tomography (OCT) findings.1-6,14 Once believed to be a disease of middle-aged, African-American women, its presentation is now recognized to affect any people of color with some suggestion of a greater prevalence among Asians.1-14 The entity has a documented incidence of only 8-13% in white patients with cases reported in Irish, French, German and Italian nationalities.3 IPCV has no obvious gender predilection.1-6 The natural course of the disease often follows a remitting-relapsing course clinically associated with chronic, multiple, recurrent serosanguinous detachments of the retinal pigment epithelium, associated neurosensory retinal detachment, and subretinal neovascularization.4 Remarkably, the long-term visual prognosis is good as long as the macula is not involved.1-13

Funduscopically, IPCV presents as subretinal orange nodules (polyps) within the choroidal vasculature.1-14 Intravenous fluorescein angiography (IVFA) poorly delineates the choroidal circulation. Indocyanine green angiography (ICGA) uses indocyanine green dye which fluoresces in the infrared spectrum, permitting enhanced imaging of structures below the RPE and overlying extravasated fluid. Its molecular size and capacity to bind to albumin allow the dye to remain in the choriocapillaris, providing the potential for detailed imaging of entities at this deep level.13-19 Active IPCV will angiographically appear as a hot spot at the location of the leaking polyps.13-19

Pathophysiology

Idiopathic polypoidal choroidal vasculopathy has been considered by many as a distinct choroidal abnormality characterized by an intrachoroidal vascular network of vessels ending in polyp-like structures.1-18,13 It is hypothesized that eyes with neovascular AMD are different than those with IPCV in that the new vascular formations exhibit substantially different structural alterations of the elastic layer in the Bruch’s membrane.8 Elastin gene (EG) polymorphisms play a role in the development of neovascularization of both entities; however, genetic differences in the EG may be among the reasons for the histopathological differences.8

Researchers using indocyanine green angiography have been able to discern two different patterns of vascularization.2,20 The first demonstrates feeder and draining vessels along with network vessels creating the characteristic findings seen in choroidal neovascularization (CNV).2,10 Points of focal dilatation on marginal vessels were comprised of polypoidal lesions.2 The second pattern demonstrated neither feeder nor draining vessels in the setting of far fewer network vessels.2 Again, the points of deformation of the network vessels appeared as polypoidal lesions.2

The researchers believe the first pattern represents a variant of deformed CNV.2,10 The second pattern is more unique and postulated to result from abnormalities of the choroidal vessels such as abnormal dilatation and hyalinization of the vessels in the setting of exudative changes in the blood plasma.2 Further changes in the basement membrane, showing deposits and granulomatous tissue suggests, at least in some cases, the condition arises from hyalinized arteriolosclerosis of choroidal vessels.2,11,12

The pathophysiology postulated to induce IPCV choroidal abnormalities in cases of myopic staphyloma and tilted disc syndrome are induced blood-flow disturbances to the region.6 Once the abnormal vessels invade Bruch’s membrane to form a polypoidal network, the RPE is pushed upward by increased intravascular pressure created by the dilated vessels and exudation from the vessels in the choroidal network.2,20

Management

In the event fluid and hemorrhage obscure observation of the choroidal detail, OCT, IVFA and ICGA can assist in diagnosis as well as guide treatment and improve post-treatment-monitoring.13,21-26

Indocyanine green angiography uses tricarbocyanine dye that is injected intravenously and is imaged as it passes through ocular vessels. An excitation filter with a peak at 805nm and a barrier filter with a transmission peak of 835nm, corresponding to the maximum fluorescence emitted by the dye in whole blood permits the capture of its pooling or leakage.12,25-27 The large molecular characteristics of the dye itself and its ability to bind to albumin allow it to remain inside the large choroidal vessels. Its fluorescent properties enable viewing in the presence of choroidal bleeding.13,26-28 Choroidal neovascularization using ICG is observed as either focal hyperfluorescence (hot spot) or diffuse hyperfluorescence (plaque). Scanning laser ophthalmoscopy (SLO) imaging allows for better visualization of feeder vessels, allowing even more selective treatment.20

Imaging the choroid with spectral-domain optical coherence tomography (SD-OCT) technology is often ineffective because of signal transmission limitations.29-32 Modifications to the instrumentation has created enhanced-depth imaging optical coherence tomography (EDI-OCT).29 This improved system permits imaging of the choroid with reasonable clarity.29-32 Enhanced-depth imaging provides in vivo cross-sectional imaging of the choroid. It is a commercially available package on most spectral-domain OCT devices.29,30 EDI-OCT demonstrates solitary or multiple polypoidal lesions with local moderate reflectivity between the RPE and Bruch’s membrane.31,32 Moderate reflectivity and an incomplete Bruch’s membrane can be seen in the presence of dome-like RPE detachments which sometimes accompany polypoidal lesions.32

Intravitreal therapy remains the standard-of-care treatment for polypoidal choroidal vasculopathy.25,33-37 Photodynamic therapy (PDT) can be used by itself or in combination with an anti-vascular endothelial growth factor inhibitor (anti-VEGF) such as ranibizumab or bevacizumab.1-4,10,11,22-25,35-40 While the addition of an anti-VEGF agent has not significantly improved outcomes or reduced polypoidal lesion recurrence, the EVEREST and PEARL studies along with others demonstrated its assistance to PDT in treating subretinal hemorrhages.34-38 For this reason, dual therapy seems to be gaining favor over PDT alone.34-38 Continuous monthly intravitreal anti-VEGF treatment has also been studied.39 While the results indicate the treatment is well tolerated with reduced polypoidal lesions, visual stabilization, resolution of subretinal hemorrhage and reduced macular edema are variable. Branching choroidal vessels remain.39

Angiographically guided laser photocoagulation targeted exclusively to the feeder vessels supplying IPCV lesions and laser directed at extrafoveal IPCV lesions is also recognized as an effective method of treatment.6,40 Laser photocoagulation is used as a last resort when other therapies fail.40

Clinical Pearls

Since choroidal neovascular membranes have the capability to grow at a rate of 10-15 microns per day, prompt referral to the retinal specialist upon suspicion of any CNV is urgent.

All modern imaging techniques such as IVFA, ICGA and OCT have a role in the accurate diagnosis and following of IPCV.

Patients found to have exudative, hemorrhagic retinopathy, without signs of active inflammation or precursors to AMD, should be considered suspicious for IPCV.

1. Yannuzzi LA, Sorenson J, Spaide RF, Lipson B. Idiopathic polypoidal choroidal vasculopathy (IPCV). 1990. Retina. 2012;32 Suppl 1:1-8.

2. Yuzawa M. Polypoidal choroidal vasculopathy. Nihon Ganka Gakkai Zasshi. 2012;116(3):200-31.

3. Ciardella AP, Donsoff IM, Huang SJ, et al. Polypoidal choroidal vasculopathy. Surv Ophthalmol. 2004;49(1):25-37.

4. McCleary CD, Guier CP, Dunbar MT. Polypoidal choroidal vasculopathy. Optometry. 2004;75(12):756-70.

5. Escaño MF, Fujii S, Ishibashi K, et al. Indocyanine green videoangiography in macular variant of idiopathic polypoidal choroidal vasculopathy. Jpn J Ophthalmol. 2000;44(3):313-6.

6. Stangos AN, Gandhi JS, Nair-Sahni J, et al. Polypoidal choroidal vasculopathy masquerading as neovascular age-related macular degeneration refractory to ranibizumab. Am J Ophthalmol. 2010;150(5):666-73.

7. Moorthy RS, Lyon AT, Rabb MF, et al. Idiopathic polypoidal choroidal vasculopathy of the macula. Ophthalmology. 1998;105(8):1380-5.

8. Kondo N, Honda S, Ishibashi K, et al. Elastin gene polymorphisms in neovascular age-related macular degeneration and polypoidal choroidal vasculopathy. Invest Ophthalmol Vis Sci. 2008;49(3):1101-5.

9. Mauget-Faÿsse M, Cornut PL, Quaranta El-Maftouhi M, Leys A. Polypoidal choroidal vasculopathy in tilted disk syndrome and high myopia with staphyloma. Am J Ophthalmol. 2006;142(6):970-5.

10. Quaranta M, Mauget-Faysse M, Coscas G. Exudative idiopathic polypoidal choroidal vasculopathy and photodynamic therapy with verteporfin. Am J Ophthalmol 2002;134(2):277-80.

11. Costa RA, Navajas EV, Farah ME, et al. Polypoidal choroidal vasculopathy: Angiographic characterization of the network vascular elements and a new treatment paradigm. Prog Retin Eye Res 2005;24(5):560-86.

12. Yuzawa M, Mori R, Kawamura A. The origins of polypoidal choroidal vasculopathy. Br J Ophthalmol 2005;89(5):602-7.

13. Stanga PE, Lim JL, Hamilton P. Indocyanine green angiography in chorioretinal diseases: indications and interpretation: an evidence-based update. Ophthalmol. 2003;110(1):15-21.

14. Laude A, Cackett PD, Vithana EN, et al. Polypoidal choroidal vasculopathy and neovascular age-related macular degeneration: same or different disease? Prog Retin Eye Res. 2010;29(1):19-29.

15. Kumar A, Nainiwal S, Prakash G. Indocyanine green angiography in age-related macular degeneration. Bombay Hosp J. 2002;44(3):333-9.

16. Alexander LJ. Exudative and nonexudative macular disorders. In: Alexander LJ, ed. Primary care of the posterior segment, 3rd Ed. New York, McGraw-Hill 2002:75-208.

17. Fernandes LH, Freund KB, Yannuzzi LA, et al. The nature of focal areas of hyperfluorescence or hot spots imaged with indocyanine green angiography. Retina 2002;22(5):557-68.

18. Berger JW, Maguire MC, Fine SL. The macular photocoagulation study. In: Kertes, P J, Conway MD, eds. Clinical trials in ophthalmology: a summary and practice guide, 1st Ed. Philadelphia; Lippincott, Williams and Wilkins 1998:71-96.

19. Nishijima K, Takahashi M, Akita J, et al. Laser photocoagulation of indocyanine green angiographically identified feeder vessels to idiopathic polypoidal choroidal vasculopathy. Am J Ophthalmol 2004;137(4):770-3.

20. Okubo A, Hirakawa M, Ito M, et al. Clinical features of early and late stage polypoidal choroidal vasculopathy characterized by lesion size and disease duration. Graefes Arch Clin Exp Ophthalmol. 2008;246(4):491-9.

21. Conrath J, Ridings B. Indocyanine green angiography in age-related macular degeneration. J Fr Ophtalmol. 2003;26(8):854-63.

22. Ueno C, Gomi F, Sawa M, Nishida K. Correlation of indocyanine green angiography and optical coherence tomography findings after intravitreal ranibizumab for polypoidal choroidal vasculopathy. Retina. 2012;32(10):2006-13.

23. Chae JB, Lee JY, Yang SJ, et al. Time-lag between subretinal fluid and pigment epithelial detachment reduction after polypoidal choroidal vasculopathy treatment. Korean J Ophthalmol. 2011;25(2):98-104.

24. Coppens G, Spielberg L, Leys A. Polypoidal choroidal vasculopathy, diagnosis and management. Bull Soc Belge Ophtalmol. 2011;(317):39-44.

25. Gomi F, Tano Y. Polypoidal choroidal vasculopathy and treatments. Curr Opin Ophthalmol. 2008;19(3):208-12.

26. Windisch R, Windisch BK, Cruess AF. Use of fluorescein and indocyanine green angiography in polypoidal choroidal vasculopathy patients following photodynamic therapy. Can J Ophthalmol. 2008;43(6):678-82.

27. Hutchinson JK, Street, M, Gurwood AS, Myers MD Face off: Fluorescein vs. OCT. Review of Optometry 2011; 148(9): 62-75.

28. Slakter JS, Yannuzzi LA, Guyer DR. Indocyanine-green angiography. Curr Opin Ophthalmol. 1995;6(3):25-32.

29. Noori J, Riazi Esfahani M, Hajizadeh F, Zaferani MM. Choroidal mapping; a novel approach for evaluating choroidal thickness and volume. J Ophthalmic Vis Res. 2012;7(2):180-5.

30. Nagase S, Miura M, Makita S, et al. High-penetration optical coherence tomography with enhanced depth imaging of polypoidal choroidal vasculopathy. Ophthalmic Surg Lasers Imaging. 2012;43(2)e5-9.

31. Ojima Y, Hangai M, Sakamoto A, et al. Improved visualization of polypoidal choroidal vasculopathy lesions using spectral-domain optical coherence tomography. Retina. 2009;29(1):52-9.

32. Li HY, Dai RP, Dong FT, Chen YX. Tomographic features of polypoidal choroidal vasculopathy lesions by spectral domain optical coherence tomography. Zhonghua Yan Ke Za Zhi. 2011;47(8):715-20.

33. Ziemssen F, Heimann H. Evaluation of verteporfin pharmakokinetics–redefining the need of photosensitizers in ophthalmology. Expert Opin Drug Metab Toxicol. 2012;8(8):1023-41.

34. Koh A, Lee WK, Chen LJ, et al. EVEREST Study: efficacy and safety of verteporfin photodynamic therapy with ranibizumab or alone versus ranibizumab monotherapy in patients with symptomatic macular polypoidal choroidal vasculopathy. Retina 2012;32(8):1453–1464

35. Gomi F, Sawa M, Wakabayashi T, et al. Efficacy of intravitreal bevacizumab combined with photodynamic therapy for polypoidal choroidal vasculopathy. Am J Ophthalmol. 2010;150(1):48-54.

36. Kim SJ, Yu HG. Efficacy of combined photodynamic therapy and intravitreal bevacizumab injection versus photodynamic therapy alone in polypoidal choroidal vasculopathy. Retina. 2011;31(9):1827-34.

37. Lee YH, Lee EK, Shin KS, et al. Intravitreal ranibizumab combined with verteporfin photodynamic therapy for treating polypoidal choroidal vasculopathy. Retina. 2011;31(7):1287-93.

38. Tomita K, Tsujikawa A, Yamashiro K, et al. Treatment of polypoidal choroidal vasculopathy with photodynamic therapy combined with intravitreal injections of ranibizumab. Am J Ophthalmol. 2012;153(1):68-80.

39. Kokame GT, Yeung L, Lai JC. Continuous anti-VEGF treatment with ranibizumab for polypoidal choroidal vasculopathy: 6-month results. Br J Ophthalmol. 2010;94(3):297-301.

40. Gemmy Cheung CM, Yeo I,Li X, et al. Argon laser with and without anti-vascular endothelial growth factor therapy for extrafoveal polypoidal choroidal vasculopathy. Am J Ophthalmol. 2013;155(2):295-304.