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igmented lesions of the choroid and are commonly encountered Pigmented lesions of by optometrists in everyday practice. The increasing use of retinal P imaging and indirect ophthalmoscopy the choroid and retina among community optometrists means more lesions will be identified. Important Chris Hemmerdinger and Professor Bertil Damato consider the clinical decisions must be made about the appearance of the lesion, the likely decisions involved in identifying and treating pigmented lesions of diagnosis and whether to monitor or the choroid and retina refer for a second opinion. In cases where an ophthalmological opinion is required, the priority of referral needs considering. Many texts and online resources are available to the practitioner to help with diagnosis. However, to research a lesion in a standard textbook requires the diagnosis. To help with such quandaries a web-based atlas of ocular tumours has been developed, categorising lesions by their position and colour rather than diagnosis (Figure 1 www.eyetumours. com). This article aims to summarise the important clinical features when seeing such patients and reviews the different pigmented lesions found in the choroid and retina. Figure 1 lesions is often described as a ball of light history is also important; if there is a History tumour atlas which travels across the visual field; it history of malignancy, metastases must Careful history taking is an essential may be intermittent or constant. be considered. part of any clinical assessment. The Less common symptoms such as float- practitioner is required to extract all ers, caused by vitreous haemorrhage, or Examination relevant facts and document impor- pain due to raised Any ophthalmic examination should tant negatives. As the history is taken or inflammation may be reported. It is include visual acuity, reactions, before the examination, refinement important to enquire about past ocular intraocular pressure and anterior and of the history may be required subse- history as lesions may have been noticed posterior segment examination. Once quently. A balance of open and closed previously and imaged or referred to the a lesion has been identified it should be questioning will allow the practitioner hospital eye service. General medical examined through a dilated pupil with a to quickly and precisely obtain a full and binocular indirect viewing system. relevant history. Visual acuity may be affected by A comprehensive history includes posterior direct macular involvement, symptoms, ophthalmic history, general , vitreous haemorrhage or medical history, a review of current . Intraocular pressure medications and family history. Many (IOP) may be elevated following vitre- patients presenting with retinal lesions ous haemorrhage, rubeosis or by lesions will be asymptomatic. They may be causing secondary angle closure. IOP attending for a routine eye examination may be reduced when there is an or be monitored for other conditions exudative detachment or with intraoc- such as diabetes. Patients attending for ular inflammation. Examination of routine examination will not usually the anterior segment examination require a dilated examination, may reveal sentinel vessels (Figure 2), and screening all patients with a dilated Figure 2 Sentinel vessels segmental cataract, anterior chamber examination would be inefficient.1 inflammation or rubeosis. Sentinel However, once a lesion has been vessels are dilated episcleral vessels, identified it should be thoroughly which are feeder vessels to the tumour. examined. Symptomatic patients with Not all prominent episcleral vessels are an intraocular tumour may complain sentinel vessels, and it is useful to look of blurred vision, field loss, , for asymmetry. Visual field loss may photopsia, metamorphopsia or pain. be noticed by the patient or picked up Blurred vision, field loss and metamor- during the examination. Such field loss phopsia may be caused by the lesion may be due to the lesion itself or second- itself or an associated retinal detach- ary to a retinal detachment. Posterior ment. Macular lesions will gener- segment examination of both is ally have a more pronounced effect essential, with relevant features being on vision. Photopsia due to choroidal Figure 3 Lesion with depigmented ‘halo’ documented as described below.

22 | Optician | 15.08.08 opticianonline.net Clinical

Documentation atrophy in pigmented scars should Figure 4 (a) Once a pigmented lesion is identified also be noted. A ring of RPE atrophy (a) flat lesion; it should be imaged and stored for surrounding a lesion tends to occur in (b) minimally comparisons at future consultations. An longstanding lesions, which may give thickened; annotated diagram should be included the appearance of a ‘halo’ around the (c) shallow in the notes documenting the level of lesion (Figure 3). dome; the lesion, colour, size, shape, position, ● Elevation – Viewing the lesion stere- (d) pronounced surface features, elevation, and the oscopically allows assessment of eleva- dome presence of any fluid. tion. Tumours should be classified as flat, ● Level of the lesion – The lesion and minimally thickened (<2mm), shallow any associated features such as haemor- dome or pronounced dome (Figure 4). (b) rhage may be choroidal, sub-retinal, Looking at deflection may intra-retinal or pre-retinal. The level of give an indicator to those observers the lesion is essential for correct diagno- without stereopsis. sis, a stereoscopic view is invaluable in ● Sub-retinal fluid – The presence or assessing this, but other cues such as the absence of fluid should be noted. This retinal vasculature may help. may be surrounding the lesion or may ● Colour – Choroidal naevi gener- gravitate inferiorly. ally appear slate grey or brown. Melanocytomas are black. Congenital Lesions hypertrophy of the retinal epithelium is Choroidal naevus (c) brown or black. Sub-retinal haemorrhage Choroidal naevi are common, benign may appear red or brown. However, it lesions that are usually round or oval must be remembered that naevi and with fairly well defined although not melanomas may be amelanotic, and sharp borders (Figures 5 and 6). The there can be considerable variation in reported incidence of choroidal naevi the appearance of retinal lesions. ranges from 0.2 to 30 per cent.2-7 This ● Size – The lesion should be measured variation is due to different study in relation to the disc (disc diameters) populations. The largest population- or with the slit lamp beam and indirect based study; the Blue Mountains eye 7 . When measuring the lesion with study reported an incidence of 6.5 per (d) an indirect lens it is essential to record cent in a white population. The major- the lens used or calculate the size incor- ity (90 per cent) are pigmented, with porating the lens magnification factor. a characteristic, grey, ophthalmoscopic Both horizontal and vertical dimen- appearance. sions should be recorded. A typical choroidal naevus is asymp- ● Shape – The lesion may be regular tomatic, less than 5mm in diameter or irregular and the margins distinct and less than 1mm in thickness, with or diffuse. This may be represented by surface , no orange pigment a diagram or annotated in the notes. (lipofuscin), not in direct contact with Certain lesions may have characteristic the disc and not associated with any sub- shapes such as the bear tracks of grouped retinal fluid. typical congenital hypertrophy of the As mentioned above, the presence of retinal pigment epithelium. drusen overlying the lesion (Figure 6) is ● Position – Ideally the lesion will indicative of chronicity, and is reassur- be imaged; however, when this is not ing. Lipofuscin (Figure 7) suggests RPE possible it is important to document dysfunction and should be viewed accurately the position of the lesion. suspiciously. Landmarks such as the disc, vascular Patients with typical naevi should be arcades and fovea are invaluable in locat- observed for any evidence of change. ing a lesion. Any contact with the optic The lesion and its relevant features must disc must be recorded. It is important to be clearly documented as described remember that the image is both later- above. Ideally the lesion should be ally and vertically inverted when using photographed, although it must be Figure 5 Typical choroidal naevus a binocular indirect ophthalmoscope. remembered that camera artefacts can ● Surface features – Drusen are a produce false impression of growth.8 If feature of chronicity and are reassur- the lesion is observed to increase in size, ing in that they indicate that the lesion the diagnosis of benign naevus must be is longstanding; the absence of drusen questioned although enlargement has over a dome-shaped, pigmented tumour been documented in naevi.9 is ominous. Orange pigment (lipofus- The main concerns with choroidal cin) implies retinal pigment epithe- naevi are and malig- lium dysfunction and always requires nant growth. onward referral for ophthalmological The majority of naevi are asymp- opinion. Non-pigmented areas such tomatic; however, they may cause as lacunae in congenital hypertrophy reduced visual acuity, flashes, floaters Figure 6 Atypical choroidal naevus with of the retinal pigment epithelium or or visual field defects. Up to 11 per overlying drusen opticianonline.net 15.08.08 | Optician | 23 Clinical

cent of naevi become symptomatic.10 Symptoms may be caused by serous retinal detachment, photorecep- tor atrophy or choroidal neovascu- larisation (Figure 8). Visual acuity is generally affected when the naevus is subfoveal.11 Treatment modalities for symptomatic naevi include transpupil- lary thermotherapy and photodynamic therapy.12 All symptomatic naevi should be referred to an ophthalmolo- gist for further investigation. Figure 7 Lesions with lipofuscin (orange Figure 8 Naevus with choroidal Malignant transformation of a naevi pigment) neovascularisation to a melanoma has been estimated to occur at an annual rate of one in 4,800 and one in 8,845.2,13 Whether a naevus has actually transformed to a melanoma or whether the melanoma was malig- nant from its inception is uncertain. In any case, risk factors for progres- sion include the increased lesion size (especially thickness), associated retinal detachment, presence of symptoms, orange pigment on the lesion, and contact with disc margin.14 If a patient has any of these risk factors the rate of malignant growth is increased so that monitoring is required. Differentiating Figure 9 Choroidal melanoma – pronounced Figure 10 Choroidal melanoma – large naevi from small melanomas dome juxtapapillary can be difficult, even for experienced observers.15 with retinal haemorrhages (Figure 11). Some melanomas are amelanotic, Table 1 which makes them diagnostically more MELANOMA acronym Melanoma of the is the common- challenging; other conditions such as est primary intraocular malignancy choroidal metastasis must be considered M – Melanoma visible externally in adults, with an annual incidence in these cases. Melanomas develop de E – Eccentric visual phenomena of approximately six per million. novo or transform from a naevus and L – Lens abnormality (cataract) Approximately 80 per cent of uveal can be found anywhere in the fundus. A – Afferent pupillary defect melanomas are choroidal, with approxi- Lesions located pre-equatorially are more N – No optical correction mately 12 per cent occurring in the easily missed on routine examinations O – and 8 per cent in the . and therefore present later, whereas M – Melanocytosis This article only discusses choroidal posterior lesions are more likely to be A – Asymmetrical episcleral vessels melanomas. detected early. Lesions near the macula Choroidal melanoma may present are more likely to be symptomatic. with a variety of symptoms or may be a For best results, early detection of Table 2 chance finding on routine eye examina- choroidal melanomas is important. A To Find Small Ocular Melanomas tion. Presenting symptoms may include mnemonic, MELANOMA, has been mnemonic photopsia, floaters, visual field loss, devised to alert the clinician to signs blurred vision and pain. Occasionally and symptoms of an intraocular tumour T – Thickness greater than 2mm choroidal melanomas present as a visible (Table 1). The acronym refers to: F – Fluid (sub-retinal) lesion, due to extra-scleral extension. Melanoma visible externally; Eccentric S – Symptoms Clinical examination of a patient with visual phenomena (eg photopsia); Lens O – Orange pigment any symptoms suggestive of melanoma abnormality, such as cataract or astig- M – Margin touching the must include anterior segment exami- matism; Afferent papillary defect; nation, intraocular pressure measure- No optical correction with spectacles; ment and indirect examination of Ocular hypertension; Melanocytosis, and those with two or more features the fundus through a dilated pupil as which predisposes to melanoma; have a greater than 50 per cent chance described earlier. and Asymmetrical episcleral vessels. of growth at five years. Tumours with Choroidal melanoma is usually seen Another mnemonic has been created two or more features should proba- as an elevated, solid, pigmented mass to remind clinicians of risk factors for bly be considered as small choroidal (Figures 9-12). Associated features may tumour growth: To Find Small Ocular melanomas.16 include orange pigment on the surface, Melanomas (Table 2).16 Tumours that Patients with suspected melanoma sub-retinal fluid overlying the tumour display none of these factors are most should be referred urgently, as early or an inferior retinal detachment. If likely naevi and have a less than 4 per treatment enhances any opportunities the melanoma breaks through Bruch’s cent chance for growth at five years. for preserving the eye and maintain- membrane it will have a collar-stud Tumours with one feature have a 38 ing some functional vision. The best appearance, which may be associated per cent chance of growth at five years route for referral may vary around

24 | Optician | 15.08.08 opticianonline.net Clinical

(MLPA). Choroidal melanomas have been associated with multiple cytoge- netic abnormalities, the most important being monosomy 3 (ie loss of one copy of chromosome 3). Patients with this cytogenetic abnormality within the melanoma have a significantly reduced survival rate.19 Estimations of survival can be made using neural networks.20 Further counselling must be given to patients who elect to have cytoge- netic studies. Although treatment for Figure 11 Choroidal melanoma – collar stud Figure 13 Indeterminate melaoncytic lesion metastatic disease only rarely seems to prolong life, patients with a non-lethal melanoma are greatly reassured by their good prognosis.

Indeterminate melanocytic lesions Although many melanocytic lesions can be classified as choroidal naevi or melanoma, even with a comprehensive examination it is not always possible to be certain of the diagnosis (Figure 13). Such cases may be classified as indeter- minate melaoncytic lesions. These must be monitored regularly to look for any evidence of change. In certain cases it Figure 12 Choroidal melanoma with inferior Figure 14 Typical solitary CHRPE may be appropriate to obtain a histo- exudative retinal detachment logical diagnosis by trans-retinal or trans-scleral biopsy. Such biopsies are the country; however, the patient will trans-retinal endoresection and enucle- only carried out after careful patient usually see a general ophthalmologist ation. The optimal treatment will vary counselling as there are surgical risks who will then refer them to a terti- according to patient requirements and and with small lesions the biopsy may ary ocular oncology unit. The patient tumour characteristics. A combination not yield enough material to provide a should be seen by an ophthalmologist of the above treatments may be used. conclusive diagnosis. within one week. If this is achievable Metastatic disease is obviously a locally via an urgent GP referral, this is concern to patients. They need to Congenital hypertrophy of the an appropriate route. If not, then refer- be appropriately counselled within retinal pigment epithelium (CHRPE) ral should be directly to an ophthalmol- the oncology service. As previously First described by Reese and Jones in ogist. It is important to keep patients mentioned the primary treatment is 1956,21 CHRPE consists of hypertro- informed, and advise them whom to to kill the tumour, estimations from phy with hyperpigmentation of the contact should they not receive an doubling times of untreated metastasis retinal pigment epithelium. Lesions are appointment by a specified date. This show most would have seeded in the typically flat and pigmented, at the level will act as a safety net to ensure prompt five years before primary treatment, of the retinal pigment epithelium (Figure treatment. ie if the tumour is one which has the 14). They are most commonly detected Diagnosis of malignant melanoma potential to metastasise, it does so very by chance on routine ocular examina- will be confirmed by the ocular oncol- early, well before the lesion is clinically tion as they are generally asymptomatic. ogist following thorough history and identified.18 In one review of patients referred examination. In addition to indirect If a tumour is removed (local resec- with suspected choroidal melanoma, ophthalmoscopy, an ultrasound scan tion, endoresection or enucleation) CHRPE was fourth in conditions of the eye will usually be enough or biopsied, then it can be studied for simulating choroidal melanoma (10 per to confirm the diagnosis. When the histological and cytogenetic features, cent of referrals), after choroidal naevi, diagnosis is in doubt, biopsy of the which can provide prognostic infor- disciform and lesion may be required. mation. Histiologically, tumours may disciform peripheral degeneration.22 The primary treatment goal is to be composed of spindle cells, epithe- It must therefore be emphasised that destroy the tumour. Preserving the lioid cells or may be mixed. Spindle- atypical lesions should be referred for eye or useful vision is often achieved, cell tumours have a better prognosis ophthalmological review. but only if the tumour is killed at the than those composed of epithelioid CHRPE lesions may be solitary or same time. The Collaborative Ocular cells. Other features associated with multiple, typical or atypical. Multiple Melanoma Study (COMS) was unable a poorer outcome are closed vascular atypical lesions include CHRPE-like to demonstrate a significant difference loops, high numbers of mitotic cells and lesions associated with familial adeno- in survival between patients whose eyes lymphocytic infiltration. Cytogenetic matous polyposis (FAP), which need to where enucleated and those who had studies involve looking at the chromo- be identified as patients are at risk of radiotherapy.17 Available treatments somes of the tumour cells; this can be associated colon cancer. include plaque radiotherapy, proton done by fluorescent in situ hybridi- Typical solitary CHRPE lesions are beam therapy, transpupillary thermo- sation (FISH) or more recently by unilateral, pigmented, well defined and therapy, trans-scleral local resection, multiplex ligation probe amplification completely flat. They may contain small opticianonline.net 15.08.08 | Optician | 25 Clinical

non-pigmented areas known as lacunae Figure 15 and may be surrounded by a non- Typical pigmented ring. Less commonly, non- grouped pigmented lesions may be seen. Rarely, CHRPE vascular sheathing may be noted over the lesion or there may be an intralesion nodual.23 While the lesions are benign, flat enlargement and enlargement of the lacunae is well documented when lesions are followed over many years.24 Multiple typical CHRPE are often recognised Figure 16 Melanocytoma by the so-called bear-tracking appear- ance (Figure 15). These lesions need to Differential diagnosis be differentiated from spindle-shaped, Figure 17 Other pigmented lesions may resemble atypical lesions associated with familial Peripheral melanoma but are beyond the scope adenomatous polyposis. exudative of this article because of their rarity. FAP is a dominantly inherited condi- haemorrhagic These include: combined hamartoma tion in which multiple polyps are present chorio- of retinal pigment epithelium and throughout the colon. Patients have retinopathy retina, pigmented choroidal metastasis, a very high risk of developing colon adenoma and adenocarcinoma of the cancer. A sensitive marker for FAP are retinal pigment epithelium and retinal atypical, flat, CHRPE like lesions. It pigment epithelial hyperplasia. should be noted that there is no relation- ship between classic CHRPE and FAP.25 Patient counselling These atypical lesions share several Patients found to have a pigmented features with typical CHRPE in that they is probably due to mild compression of lesion all need to be carefully and are well circumscribed, flat, may contain the optic disc fibres. tactfully informed of the findings. This lacunae or have a surrounding halo. Although considered a benign lesion requires skill so as not to cause excess Atypical lesions in contrast to CHRPE subtle growth is seen in up to 15 per anxiety in a patient with an apparently are pisciform (fish-shaped) or spindle- cent, the main predictive factor for benign lesion, at the same time, not shaped, bilateral and multiple.26 enlargement being a thickness of giving false reassurance to a patient with 1.5mm at presentation.29 Malignant a malignant melanoma. It is perfectly Melanocytoma transformation has been reported in 1-2 acceptable to inform patients of any Clinically, melanocytomas are typically per cent. It is important to differentiate diagnostic uncertainties. All patients black. melanocytomas, melanocytoma from uveal melanoma. referred with pigmented lesions must which are the most common, are located Both present at a similar age; however, be informed of when they are likely to partly or entirely within the optic disc, melanomas are rare in dark-skinned be seen by an ophthalmologist and what often extending over the disc margin individuals, whereas melanocytomas they should do if they do not receive an into adjacent choroid or neurosensory have an equal incidence in all races. appointment within a specified time. It retina (Figure 16). The vast majority of There appears to be a slight preponder- is not within the remit of the optometrist lesions are unilateral, although cases of ance for females.29 to provide counselling about treatment bilateral optic disc melanocytomas have Management of melanocytoma is and prognosis, which will be done by been reported.27 generally observation with serial photog- a multidisciplinary team at an ocular Historically, melanocytomas were raphy. Annual follow-up is required due oncology centre. thought of as malignant neoplasms of to the risk of malignant transformation. the optic nerve; however, they are now Given the variable clinical appearance Conclusions recognised as benign with an excellent and malignant potential of melanocy- Optometrists are becoming increas- prognosis.28 The term melanocytoma toma, patients with this tumour should ingly involved in primary eye-care was adopted by Zimmerman based on be referred for ophthalmological assess- provision. Given the ever-increasing similarities to ocular melanocytosis. ment and surveillance. use of indirect viewing techniques Others have suggested terms such as and availability of retinal photography, hyperpigmented magnocellular naevus Peripheral exudative haemorrhagic pigmented lesions in the ocular fundus of the optic disc (HMNOD) may be more chorioretinopathy will present important management appropriate,28 although this terminology Neovascular changes in age-related issues to optometrists. Optometrists has not been widely accepted. macular degeneration are well known need to be able to decide which lesions Melanocytomas cause mild visual to optometrists. These changes, which can be safely observed and which loss in about a one in four patients.29,30 usually occur in the macular area, do patients should be referred on for Severe visual loss is uncommon, but not usually represent too much of a ophthalmological opinion. ● may be caused by central retinal vein diagnostic challenge. Peripheral neovas- occlusion, tumour necrosis or malig- cular changes are well documented,32 A list of references is available from the nant transformation. Afferent pupillary and are often mistaken for melanomas clinical editor: [email protected] defects have been reported in up to 30 on initial examination33 (Figure 17). In per cent of patients and field defects in cases where ultrasound and visualisa- ● Chris Hemmerdinger is specialist up to 90 per cent; these include enlarge- tion of the tumour are not sufficient registrar at the Royal Liverpool University ment of the blind spot, nerve fibre for diagnosis, serial examinations will Hospital. Professor Damato is consultant bundle defects and nasal steps.31 The show haemorrhagic lesions to decrease ophthalmologist and director of the mechanism for pupillary and field loss in size whereas melanomas grow. Liverpool Ocular Oncology Service

26 | Optician | 15.08.08 opticianonline.net