Recurrent idiopathic neuroretinitis: the role of optical coherence tomography in a challenging diagnosis.

Neuroretinitis (NR) is characterised by optic disc oedema associated with macular exudates in a star-shaped pattern. Several aetiologies of NR have been described, with cat-scratch disease being the most common. However, despite thorough investigations, one-quarter of cases are classified as idiopathic neuroretinitis (INR), in which visual prognosis is generally good. Conversely, some patients present with recurrent attacks and no improvement in visual function, raising the hypothesis that this presentation represents a different subset of INR, simply termed recurrent INR (RINR). Given that the diagnosis of RINR is challenging, ancillary exams using techniques such as optical coherence tomography (OCT) are usually required. Here, we report a case of RINR in which OCT played a key role in early diagnosis and treatment, mainly through the measurements of the peripapillary retinal nerve fibre layer and macular ganglion cell layer enabling the detection of early neuroaxonal loss and early treatment.