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Determining whether delayed nonarteritic ischemic optic neuropathy associated with cataract extraction is a true
Ly T Nguyen1, Michael J Taravella, Victoria S Pelak
1Department of Ophthalmology, Denver Veterans Affairs Medical Center, Rocky Mountain Lions Eye Institute, University of Colorado Health Sciences Center, Aurora, Colorado, USA.
Journal of Cataract and Refractive Surgery
|December 2, 2006
Summary
Delayed nonarteritic ischemic optic neuropathy (NAION) after cataract extraction is rare. Current data do not support a causal link, and the timing of susceptibility remains unclear.
Area of Science:
- Ophthalmology
- Neuro-ophthalmology
- Vascular Neurology
Background:
- Cataract extraction is a common surgical procedure.
- Delayed nonarteritic anterior and posterior ischemic optic neuropathy (NAION) has been anecdotally linked to cataract surgery.
- The precise timing and causality of this association require further investigation.
Purpose of the Study:
- To evaluate cases of delayed NAION occurring after cataract extraction.
- To assess the need for prospective reporting of NAION post-cataract surgery.
Main Methods:
- Retrospective review of patients diagnosed with NAION at two medical centers.
- Inclusion criteria: NAION occurring 2 to 12 months after cataract extraction.
- Data analysis focused on timing and patient characteristics.
Main Results:
- Seven cases of delayed NAION were identified in 5 patients (2 bilateral).
- Onset ranged from 2 to 6 months post-cataract extraction in most cases.
- One patient experienced bilateral NAION in fellow eyes, occurring 3 months and 5 months after sequential cataract extractions.
Conclusions:
- The current study does not establish a causal relationship between cataract extraction and delayed NAION.
- The period of increased susceptibility for NAION following cataract surgery remains undefined.
- Centralized prospective reporting of NAION after cataract extraction may be warranted.
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