Outer retinal tubulations in maternally inherited diabetes & deafness - associated macular dystrophy: case report

To describe the presence of outer retinal tubulations (ORTs) in a patient diagnosed with maternally inherited diabetes and deafness (MIDD) - associated macular dystrophy.

The patient underwent clinical examination assessing best-corrected visual acuity (BCVA), anterior segment evaluation and fundoscopy followed by optical coherence tomography (OCT). Audiological evaluation was also performed for the accurate diagnosis of MIDD.

A 57-year-old diabetic patient with mildly affected BCVA, macular dystrophy and severe neurosensory hearing loss was diagnosed with MIDD. Examination with OCT revealed the central loss of photoreceptors and the presence of ORTs in close proximity to the fovea. Regular follow-up seven months after her initial visit showed no alterations in the clinical and imaging status of the patient. In the context of family screening, the patient's sister presented with the diagnosis of pre-diabetes and a moderate sensorineural hearing loss, while fundus examination and OCT revealed no significant pathology. In this report, we present ORTs in association with MIDD.

ORTs are a non-specific finding that can be found in MIDD and other retinal dystrophies. Taking under consideration the rarity and the difficulty in diagnosing this entity, our data could serve as an addition to the existing knowledge in terms of clinical and imaging manifestations of MIDD.