Management of non-arteritic anterior ischemic optic neuropathy

Could Buerger's disease cause nonarteritic anterior ischemic optic neuropathy?: a rare case report

We present an interesting case with nonarteritic anterior ischemic optic neuropathy (NAION) accompanied by Buerger's disease. A 43-year-old man was referred to our neuro-ophthalmology clinic with a complaint of visual deterioration in the left eye that started 5 days ago. He suffered from Buerger's disease, and he had acute pain in the right lower limb below the knee. His best corrected visual acuity was 10/10 in the right eye and 2/10 in the left eye by Snellen chart. There was a relative afferent pupil defect in the left eye. The right optic disc was normal on fundus examination, and blurring, hemorrhagic swelling was found at the left optic disc. Inferior altitudinal visual field defect was observed in the left eye. Neurological examination was normal. Computed tomography angiography scan revealed occlusion in the right posterior tibial artery. Brain imaging and laboratory tests such as blood analyses, genetic screening, coagulation, and lipid panels were unremarkable. NAION may occur in patients with Buerger's disease, but it is extremely rare. Therefore, clinicians should be aware of this rare association.

Peripapillary Pachychoroid in Nonarteritic Anterior Ischemic Optic Neuropathy

Purpose

This study examined the peripapillary choroidal thickness (PCT) in nonarteritic ischemic optic neuropathy (NAION) in comparison to contralateral eyes and normal eyes.

Methods

We used enhanced depth imaging spectral-domain optical coherence tomography to image the optic nerve head of 20 NAION, 10 contralateral eyes, and 102 normal eyes. Following compensation, the scans were manually delineated to identify relevant surfaces including Bruch's membrane opening (BMO), Bruch's membrane, and anterior sclera. The PCT was defined as the measurement between Bruch's membrane and the anterior sclera and was measured at increasing distance from BMO. Models adjusted for age, BMO area, and axial length were used to compare the mean PCT between NAION and normal eyes, and contralateral eyes and normal eyes. Paired t-tests were used to compare the PCT between NAION and contralateral eyes.

Results

The mean PCT was thicker in NAION and contralateral eyes when compared with normal eyes at all distances from BMO (P < 0.001). The PCT was not significantly thicker in contralateral eyes when compared with affected NAION eyes. Choroidal thickness was thinnest in the inferior quadrant in all eyes regardless of the group.

Conclusions

Increased peripapillary choroidal thickness was noted in both NAION and contralateral eyes. The thicker choroid may be an associated feature or a result of the disorder. Although further longitudinal study is required to determine causation, these findings may suggest that a thickened peripapillary choroid may be a component of the disk-at-risk clinical phenotype.

Ischemic optic neuropathies - where are we now?

Ischemic optic neuropathy is of two types: anterior and posterior. Non-arteritic anterior ischemic optic neuropathy (NA-AION) is the most common type of ischemic optic neuropathy. There are three major misconceptions about NA-AION: (1) that its pathogenesis is not known, (2) that NA-AION and ischemic cerebral stroke are similar in nature, pathogenetically and in management, and (3) that there is no treatment. All these misconceptions are based on lack of in-depth knowledge of the subject. They are discussed in the light of our current scientific knowledge. The pathogenesis of NA-AION is known but is highly complex. NA-AION and ischemic cerebral stroke are very different clinical entities, pathogenetically and in management. Aspirin has no beneficial effect. Corticosteroid therapy during the initial stages can be beneficial. To reduce the risk of development of NA-AION in the other eye or of further visual loss in the same eye, it is essential to reduce as many risk factors as possible. Management of arteritic anterior ischemic optic neuropathy and of posterior ischemic optic neuropathy is discussed.

Intravitreal ranibizumab injection for nonarteritic ischemic optic neuropathy

PURPOSE

The aim of this study was to evaluate the functional and morphological outcomes of intravitreal ranibizumab injection (IVR) in the treatment of nonarteritic ischemic optic neuropathy (NAION).

METHODS

Three patients with NAION of 1–2 days onset underwent IVR. A complete ophthalmologic examination was performed at baseline (before IVR) and at 1 day, 1 week, 1 month, 6 months, and 1 year following IVR.

RESULTS

In all patients, we found an early resolution of optic disk swelling, as soon as 1 week after IVR; however, such a morphological improvement was not accompanied by a corresponding functional (visual acuity and perimetric) improvement. The first treated patient presented a good visual acuity and a relative central visual field defect at baseline, and at the 12-month follow-up, we found an overall functional stabilization, with no further visual acuity and visual field deterioration. The second and third treated patients presented a lower visual acuity and an absolute center-involving visual field defect at baseline. In these patients, despite early papillary edema resolution, late optic nerve atrophy occurred, and visual acuity and visual field did not improve at the 12-month follow-up.

CONCLUSION

The results from our study suggest that even if IVR is effective in reducing optic nerve swelling in NAION patients, no functional improvement may be observed. Further studies are necessary to definitively establish the efficacy and safety of IVR in the treatment of NAION.