Conclusion
In diagnosing this lesion we considered it's shape and it's colour, we decided that it wasn't raised, although the two dimensional perception of blood vessel path might contradict the more reliable three dimensional visualisation. We noted that the edges were well defined but had some pigment variation both at the edges, and indeed across the lesion itself. The surrounding blood vessels appeared normal. There were some small drusen on the lesion, and in particular at the edges. We also considered the possibility of a small area of sub choroidal haemorrhage. We considered the patients past liposarcoma history, and at the same time tried to ignore it !
Naevus or Melanoma ? Melanoma or Naevus ?
The problem with this lesion was that it wasn't typical enough of routine naevi to allow sufficient confidence that we could simply review this case after a period of time. We felt that this was deserving of Ophthalmological opinion, but at the same time would schedule our own review.
The patient has been seen at hospital level, currently awaits both ultrasound examination and the hospital's own retinal imaging, and is frustrated by the slow pace. It may be that our own follow up may occur before any hospital conclusion, and we are in a good position to provide accurate and reliable assessment of any visual change to this lesion, and hope that this might provide the first stage of ongoing reassurance for this patient.
The interesting things about this case are firstly the difficulty in actually viewing this lesion. The quality of the images taken through a Volk lens if they had been more central would perhaps be judged average or even poor, but to acquire any image at all in the extreme periphery, as here, is actually quite an achievement. From a clinical point of view the interesting things are firstly the difficulties of certainty of diagnosis with an unusual combination of features. It also demonstrates nicely the difficulties faced by every working Optometrist every day of life, not to mention the jeopardy involved therein.
So what have we learned so far ? ......
Firstly, how easily this might have been missed.
Secondly that despite a high level of clinical care, and with the best intentions and the best will in the world, the limitations of an eye examination, the limitations of resources and the limitations of the instrumentation that we have available to us mean that it is inevitable that on occasion some features will remain undetected.
Thirdly there is probably a strong argument for the dilation of every patient that walks through our doors.
Fourth, .... use all of your instrumentation to best advantage, but never in isolation or as a replacement for an overlapping method.
Fifth and finally, .... DRI is probably now pretty commonplace in routine examination, but there is a place and a similar strong justification for routine DAI, as a diagnostic aid, for future comparison, for the ability to actually show the patient what you are talking about, for your own protection and defence in litigation. Daily use of a digital biomicroscope allows not only DAI, but with the use of a Volk lens provides the ability to produce DRI images that are not achievable with a retinal camera. Most importantly this can be part of a drive to continually seek to raise the standard of ongoing clinical care. |