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Updated: Jul 28, 2026
14:54
Rat Model of Photochemically-Induced Posterior Ischemic Optic Neuropathy
Published on: November 29, 2015
Posterior ischaemic optic neuropathy: clinical features, pathogenesis, and management
1Department of Ophthalmology and Visual Sciences, College of Medicine, University of Iowa, Iowa City, IA 52242-1091, USA. sohan-hayreh@uiowa.edu
Eye (London, England)
|November 10, 2004
Summary
Posterior ischaemic optic neuropathy (PION) often causes severe vision loss. Early high-dose steroid treatment can significantly improve vision in nonarteritic PION cases.
Area of Science:
- Ophthalmology
- Neurology
Background:
- Posterior ischaemic optic neuropathy (PION) is a condition affecting optic nerve blood supply.
- Understanding its clinical features, pathogenesis, and management is crucial for patient outcomes.
Purpose of the Study:
- To comprehensively investigate and present the clinical features, pathogenesis, and management of PION.
- To differentiate between arteritic, nonarteritic, and surgical PION.
Main Methods:
- Retrospective study of 53 eyes from 42 PION patients.
- Systematic evaluation including ophthalmic examination, visual field testing, and fluorescein fundus angiography.
- Giant cell arteritis (GCA) screening for patients aged 50+.
Main Results:
- PION types: 35 nonarteritic, 14 arteritic, 4 surgical.
- Significant visual acuity loss was common, particularly central visual field defects.
- High-dose steroids improved vision in early nonarteritic PION, but not arteritic or surgical PION.
Conclusions:
- PION requires diagnosis by exclusion, with GCA ruled out in patients over 50.
- Early high-dose steroid therapy shows promise for nonarteritic PION visual recovery.
- Arteritic and surgical PION have poorer prognoses with steroid treatment.
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