Clinical igmented lesions of the choroid and retina are commonly encountered Pigmented lesions of by optometrists in everyday practice. The increasing use of retinal Pimaging 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 Eye 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 intraocular pressure Any ophthalmic examination should tant negatives. As the history is taken or inflammation may be reported. It is include visual acuity, pupil 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 cataract, vitreous haemorrhage or medical history, a review of current retinal detachment. 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 fundus 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, floaters, 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 eyes 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 blood vessel 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 lens. 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 drusen, 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 visual impairment 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