Chen, John J.

Papilledema is optic nerve swelling caused by increased intracranial pressure, which has the potential to cause significant vision loss. Papilledema is typically bilateral and symmetric but can sometimes be asymmetric and even unilateral. The cause for this asymmetry is unknown. The purpose of this study was to utilize ultrasound vibro-elastography (UVE) to assess for biomechanical differences in eyes with papilledema. Nine patients with papilledema and 9 age-matched controls were enrolled. An external harmonic vibration was used to generate wave propagation through the eyelid with three excitation frequencies of 100, 150, and 200 Hz. A 6.4 MHz ultrasound probe was used to noninvasively measure the wave propagation in the posterior sclera to provide shear wave speeds and viscoelasticity (fit with Voigt model). The magnitudes of the shear wave speed and viscoelasticity of the idiopathic intracranial hypertension patients’ posterior sclera were significantly higher than those of healthy subjects. Moreover, for patients with unilateral papilledema, the magnitudes of wave speed and viscoelasticity of the posterior sclera were statistically higher in eyes with papilledema than in the contralateral eyes without papilledema. UVE provides a noninvasive technique to measure the viscoelastic properties of the posterior sclera, which is stiffer in eyes with papilledema.

Introduction: Antineutrophil cytoplasm antibody-associated vasculitides encompass a diverse spectrum of autoimmune diseases characterized by necrotizing small vessel vasculitis. Ocular manifestations may be the presenting findings of antineutrophil cytoplasm antibody-associated vasculitides. Methods: Single, retrospective case study. Results: We report the rare case of a 55-year-old woman with a cilioretinal artery occlusion as the presenting feature of perinuclear antineutrophil cytoplasm antibody-associated microscopic polyangiitis. Conclusions: Although rare, antineutrophil cytoplasm antibody-related vasculitis should be considered in any retinal vascular occlusion, particularly in the setting of patients with new vague headaches and a paucity of vasculopathic risk factors.

Study Design. Case–control analysis and systematic literature review. Objective. To illustrate the prognosis and perioperative risk factors associated with this condition. Summary of Background Data. Ischemic optic neuropathy (ION) is the most common pathological diagnosis underlying postoperative vision loss. It comes in two primary forms—anterior (AION)—affecting the optic disc or posterior (PION) affecting the optic nerve proximal to the disc. Spine surgery remains one of the largest sources of acute perioperative visual loss. Methods. We performed a 1:4 case–control analysis (by age and year of surgery) for patients with ION and those who didn’t develop ION following spine surgery at our institution. A systematic literature search of Medline, Embase, Scopus from inception to September 2017 as also performed. Results. We identified 12 cases from our institution. Comparison to 48 matched controls revealed fusion, higher number of operative levels, blood loss, and change in hemoglobin, hematocrit to be significantly associated with ION. Majority were diagnosed with PION (83%, 10/12) and had bilateral presentation (75%, 9/12). Only 30% patients (3/10) demonstrated improvement in visual acuity while the rest remained either unchanged (40%, 4/10) or worsened (20%, 2/10) at last follow-up. Literature review identified 182 cases from 42 studies. Posterior ischemic optic neuropathy (PION) was found in 58.7% (114/194) of cases, anterior ischemic optic neuropathy (AION) in 17% (33/19) and unspecified ION in 24% (47/194). PION was associated with higher odds of severe visual deficit at immediate presentation (odds ratio [OR]: 6.45, confidence interval [CI]: 1.04–54.3, P = 0.04) and last follow-up. Conclusion. PION is the most common cause of vision loss following spine surgery and causes more severe visual deficits compared with AION. Prone spine surgery especially multi-level fusions with longer operative time, higher blood loss, and intraoperative hypotension are most associated with the development of this devastating complication. Level of Evidence: 3