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Posterior ischemic optic neuropathy — Clinical Guidelines

Overview

Posterior ischemic optic neuropathy (PION) is characterized by ischemic damage to the posterior portion of the optic nerve, leading to acute or subacute vision loss, often without optic disc swelling. It can occur in various clinical settings, including perioperative periods following surgeries, systemic vascular diseases, and giant cell arteritis 4.

Diagnosis

Sudden vision loss, typically monocular

Absence of optic disc swelling

Delayed optic nerve head perfusion on fluorescein angiography (in some cases) 3

Visual field defects consistent with nerve fiber layer involvement

Histopathological evidence of ischemic changes in the posterior optic nerve (in autopsy cases) 7

Management

Supportive care: Early recognition and management of underlying causes

Monitoring: Regular visual acuity assessments and visual field testing 5

Avoidance of exacerbating factors: Minimize hemodynamic hypotension, anemia, and overtransfusion during and after surgery 5

No specific pharmacological treatment universally recommended; focus on managing comorbidities (e.g., carotid artery disease) 4

Special Populations

Perioperative patients: Increased risk with prolonged surgeries and steep Trendelenburg positioning; monitor closely 1 2

Elderly: Higher prevalence of associated systemic vascular diseases, potentially leading to worse outcomes 4

Key Recommendations

Monitor visual acuity and fields postoperatively in patients undergoing prolonged surgeries, especially those involving steep head positioning (Evidence: Moderate 1 2)

Manage and prevent systemic risk factors such as carotid artery disease and hypotension to improve visual outcomes in nonarteritic PION (Evidence: Moderate 4)

Consider PION in differential diagnosis for sudden vision loss post-surgery, even in minimally invasive procedures (Evidence: Moderate 1 2 3)

References

1 Weber ED, Colyer MH, Lesser RL, Subramanian PS. Posterior ischemic optic neuropathy after minimally invasive prostatectomy. Journal of neuro-ophthalmology : the official journal of the North American Neuro-Ophthalmology Society 2007. link 2 Metwalli AR, Davis RG, Donovan JF. Visual impairment after laparoscopic donor nephrectomy. Journal of endourology 2004. link 3 Luscavage LE, Volpe NJ, Liss R. Posterior ischemic optic neuropathy after uncomplicated cataract extraction. American journal of ophthalmology 2001. link00955-2) 4 Sadda SR, Nee M, Miller NR, Biousse V, Newman NJ, Kouzis A. Clinical spectrum of posterior ischemic optic neuropathy. American journal of ophthalmology 2001. link01199-0) 5 Schobel GA, Schmidbauer M, Millesi W, Undt G. Posterior ischemic optic neuropathy following bilateral radical neck dissection. International journal of oral and maxillofacial surgery 1995. link80030-1) 6 Sonty S, Schwartz B. Development of cupping and pallor in posterior ischemic optic neuropathy. International ophthalmology 1983. link 7 Isayama Y, Takahashi T. Posterior ischemic optic neuropathy. II. Histopathology of the idiopathic form. Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift fur Augenheilkunde 1983. link

Posterior ischemic optic neuropathy