ACTA ENDOCRINOLOGICA (BUC)

Context. Optical Coherence Tomography (OCT) is a non-invasive diagnostic imaging technique, providing histological-like, high resolution transverse-section images of the eye structures. Objective. To quantify optic nerve’s alterations in optochiasmatic syndrome by OCT and with a classical investigation: visual field. Design. We present a patient with a giant pituitary tumor and chiasmatic compression, first seen in 2013, treated and reassessed in 2014. Subjects and Methods. Patient demanded an ophthalmological exam because of visual disturbances. Ophthalmic exam included: visual field (VF) test (with automated static perimetry – Oculus Centerfield), measurements of the Retinal Nerve Fibre Layer (RNFL) and optic nerve head (ONH) by OCT scans – using a Stratus Zeiss 3000 device. Brain MRI was made and the patient was then assessed by endocrinologist. Results. Patient has bitemporal hemianopia. OCT showed, in both eyes, slight optic disc (ONH) edema and RNFL loss, mainly in the nasal quadrant (optic nerve “band atrophy”), correspondent with visual field temporal defect. Brain MRI and endocrine evaluation revealed a macroprolactinoma, optochiasmatic syndrome, panhypopituitarism and abdominal obesity. Under treatment we noted significant reduction in tumour size, correlated with remission of ONH edema and visual field almost normalized. Reviewed published data about visual field defects and optic nerve OCT measurements, in different types of pituitary tumours, fits well the case presented. Conclusions. OCT is a very useful and accurate objective investigation for diagnosis and follow-up in structural optic nerve changes caused by chiasmatic compression. Measurements are complementary to those provided by perimetry – a subjective, functional investigation, depending on patient skills.