Case of the Month: May 2015

Written by Dr James Wong

A 55 year old Asian male presented with a 10 day history of blurred vision and a central scotoma in his left eye. He had no associated ocular pain or prodromal symptoms. He was in good general health with mild osteopenia however no history of hypertension or diabetes. He was an ex-smoker and did not have any family history of any ocular disorders.  On clinical examination he was emmetropic and his visual acuity was 6/6 in his right eye and 6/15 in left eye. Intraocular pressures were normal and his anterior segment was normal.

Dilated fundus examination of his left eye revealed an area of elevation of the macula with some lipid hard exudate, an orange nodule and haemorrhage. There were some hard drusen and retinal pigment epithelial changes at his right macula (Fig 1).

Figure 1

Figure 1

An OCT (Optical Coherence Tomography) scan of his left macula revealed subretinal fluid and a pigment epithelial detachment (Fig 2).

Figure 2

Figure 2

He had a fluorescein angiogram and this revealed an occult type of choroidal neovascular membrane in his left macula (Fig 3a). An ICG (Indocyanine Green) angiogram revealed a round lesion which was actively leaking (Fig 3b).

Figure 3a (Left)     Figure 3b (Right)

Figure 3a (Left) Figure 3b (Right)

Discussion

This patient presents with an acute lesion which is actively bleeding and leaking in the left macula causing reduced vision. The differential diagnoses of this patient would include typical exudative (“wet”) Macular Degeneration (MD), a macroaneursym of the retinal artery, central serous retinopathy and polypoidal choroidal vasculopathy.  Typical “wet” macular degeneration, (particularly the more aggressive types) can present in this fashion, however the patient is at a slightly younger age group than is typical for standard MD. A macroaneurysm of the retinal artery is more commonly associated with hypertension, particularly in older females and this patient was normotensive. Central serous retinopathy can cause subretinal fluid and often affect Asian patients, however is not usually associated with haemorrhage and hard exudate. The diagnosis in this case is polypoidal choroidal vasculopathy or “PCV”.

PCV was first described by Yannuzzi in 1982 and is commonly regarded as a variant of wet Macular Degeneration.  The “polyps” are not cancerous, however are grape-like balloons associated with the underlying choroidal blood vessels. It is often found in Asian or dark-skinned individuals and may constitute up to 50% of all wet MD cases, however can be also found in Caucasian people in up to about 10% of all wet MD cases. It also often presents at a younger age than typical wet MD. It is a highly variable condition and its natural course can range from a benign condition not requiring any treatment to a very aggressive type of bleeding which can result in blindness if not treated adequately.  Common clinical features include orange nodules which are the “polyps”, serous elevation of the macula (subretinal fluid), pigment epithelial detachments, haemorrhage and lipid hard exudate. It can be sometimes easily confused with other retinal conditions such as central serous retinopathy (CSR). The diagnosis of PCV is usually made by clinical fundus examination at the slit-lamp, OCT, fluorescein angiography and most importantly ICG angiography. ICG angiography is the gold standard for differentiating PCV from typical types of wet Macular Degeneration. Interestingly, there are many patients who are affected by PCV only in one eye, unlike typical wet MD which usually eventually affects both eyes. The treatment for PCV can be similar to treatment for typical wet MD in the form of intravitreal anti-VEGF injections (ranibizumab, bevacizumab, aflibercept), initially however there are some PCV patients who respond better to a combination treatment of anti-VEGF injections and verteporfin photodynamic therapy (PDT “cold” laser). There are currently clinical trials underway to best evaluate the best treatment for PCV. This patient was initially treated with anti-VEGF injections and demonstrated an improvement after 3 months of treatment with an improvement in vision to 6/7.5 (Figure 5).

Figure 5: before (Top) and after (Bottom) treatment with anti-VEGF injections

Figure 5: before (Top) and after (Bottom) treatment with anti-VEGF injections

This case highlights that it is important to have a high degree of clinical suspicion for this disorder which is often under-diagnosed and adequate techniques to investigate a patient with any form of leakage at the macula.