Patterns of Optic Disc Swelling Found as Prognostic Marker in NAION

VF defects improved or remained stable in 57% of patients, while the other 42% of patients displayed significant VF deterioration, with a doubling of the absolute number of VF defects. Photo: Neil Miller, MD. Click image to enlarge. Due to its frequency in older adults, nonarteritic anterior ischemic optic neuropathy (NAION) should always be kept in mind by eyecare practitioners dealing with patients who experience sudden, painless vision loss. Also due to NAION’s frequency, researchers and clinicians alike are interested in elucidating what potential prognostic markers may exist, as to better aid patients and doctors in dealing with the condition.The Journal of Neuro-Ophthalmology recently published a paper in which researchers investigated the clinical course of NAION with respect to individual prognostic markers. The study was based in Germany at the University Eye Clinic in Tubingen. The retrospective study included 116 total eyes of 100 patients; 63% of patients were men and median age was 61.5 years. It was found with analysis that obstructive sleep apnea occurred in 73.5% of patients, arterial hypertension occurred in 69.9% and second eye involvement happened in 15%. Median follow-up was 56 days.Median visual acuity (VA) in decimals was 0.63 in the first test and 0.5 in the final test, and a clinically relevant decrease in VA of at least two lines occurred in 27.5%. Visual field (VF) defects worsened in 42.5%, and both the worst VA and VF prognosis were seen in relation to initial circular swelling of the optic disc. Conversely, best final VA was linked with initial superior swelling, while best final VF findings were seen with initial inferior swelling. A considerable increase in optic disc swelling also happened during the observation period in 16.4% of eyes, at a median of 24 days after initial presentation, and particularly affected men with initially good VA, who showed a two-stage progression of optic disc swelling with poor visual prognosis.Upon discussion, the authors of the paper compare their findings with past literature. One mentioned is the Quark study, in which the age of NAION patients was similar with the current cohort, the proportion of women was slightly lower, but had a significantly lower incidence of obstructive sleep apnea than in the current study (19.1% vs. 73.5%). The investigators reason that this could be due to them initiating a corresponding screening exam for sleep apnea for all patients, while the Quark study was unclear in whether only known risk factors were documented or if diagnostic tests were ordered as well.However, other studies document a strong link between NAION and obstructive sleep apnea, with the risk of NAION occurring in patients with this type of sleep apnea being up to six times higher, and another study reporting 75% of patients with NAION having obstructive sleep apnea.The authors also highlight that this study found a previously unreported observation of the two-stage optic disc swelling more common in men with initial good VA and ultimately resulting in poorer final VA. This, along with their other findings, prompts the authors to write that “knowing this connection is important for individual patient counseling and can help to reduce uncertainty for both the patient and the treating [provider].”Click here for the journal source. Tonagel F, Wilhelm H, Birk M, Kelbsch C. Individual prognosis and clinical course of nonarteritic anterior ischemic optic neuropathy. J Neuroophthalmol. 2025;00:1-5.