Optic Disc Drusen and NA-AION
Journal of Neuro-Ophthalmology
Published online Jan. 16, 2020
Rueløkke et al. compared the prevalence of known risk factors for nonarteritic anterior ischemic optic neuropathy (NA-AION) in patients with the condition and in a subset of those with optic disc drusen (ODD-AION). They found that ODD may be a risk factor in the development of AION.
The researchers evaluated 27 patients with NA-AION; all were originally treated between 2008 and 2017. For this case-control study, the patients were questioned about their medical history and were asked about general vascular risk factors (diabetes, hypertension, dyslipidemia, and smoking) and other risk factors for NA-AION (sleep apnea, anemia at time of diagnosis, and ocular surgery before diagnosis). The patients were imaged with optical coherence tomography with enhanced depth imaging (EDI-OCT) to confirm the presence or absence of ODD.
All told, 14 patients had no ODD, and 13 had ODD-AION. Four of the 13 with ODD-AION (31%) had vascular risk factors; in contrast, 12 of the 14 with no ODD (86%) had vascular risk factors. Five patients with ODD-AION (38%) had previous ocular surgery, versus one patient with no ODD (7%).
Of note, during EDI-OCT screening for this study, two of the patients were found to have buried ODD and were reclassified. This finding implies that not all otherwise healthy NA-AION patients had originally undergone thorough screening, the authors said, and they added that cases of ODD-AION may be underdiagnosed. In particular, they noted that optic disc edema during the acute stage of the disease can mask ODD on EDI-OCT, and they suggested scanning during follow-up.
The original article can be found here.