Figure 1 shows an image taken from a patient using the Topcon OCT 2000 and clearly shows a large oval lesion at the macula and a perivascular chorioretinal atrophy along the superior vascular arcade.
The latter indicates an isolated inflammatory event coincident with the macular condition.
Figure 2 is the other eye of the same patient showing a similar macular appearance. The patient had been referred for a low vision assessment with a diagnosis of simply 'cone dystrophy'. This term refers to a number of conditions where there is an inherited dystrophy of the cone receptors leading to progressive central vision loss (in this case the patient had logMAR acuities of R1.0 and L 1.1), loss of colour vision and light sensitivity. In this patient the photosensitivity was the most disabling complaint and dark filters (in an appliance acceptable to a 14-year-old!) were the most gratefully accepted of all that we prescribed. Vision had first been lost from around the age of seven and the disciform central lesion was well established at first meeting with us, some seven years after first diagnosis.
As stated, cone dystrophies include a variety of conditions and they are distinct from other inherited macular dystrophies, perhaps Stargardt's being the most well known. In this case, Stargardt's cannot be ruled out here as, if one looks at the central lesion, one may also see a scattering of lighter lesions around the central dystrophic zone which may well be part of the fundus flavimaculatus condition one expects with Stargardt's. The vision loss and later photophobia is also consistent with the Stargardt's diagnosis. The retinal analysis on the OCT (Figures 3 and 4) show extensive tissue loss in the central retina.
Treatment was not indicated and ongoing low vision provision is the case here, tailored to the patient's education and now early employment needs. ?