Drusen Optic Neuropathy
- Optic neuropathy associated with optic disc-embedded hyaline bodies called “drusen,” which are mitochondria ejected from damaged axons
- May be caused by crowding in a narrow scleral canal
- Often misdiagnosed as papilledema
- Glistening nuggets that protrude from the optic disc or are buried beneath its surface
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Buried drusen may be revealed by
- Autofluorescence fundus photography
- B-scan ultrasound
- Optical coherence tomography
- Orbit CT
- Nerve fiber bundle visual field defects, sparing the maculopapillar bundle, reflect loss of axons
- Papilledema
- Papillitis
- Ischemic optic neuropathy
- Diabetic papillopathy
- Leber hereditary optic neuropathy
- Look for drusen with ophthalmoscopy or ancillary studies
- Order brain MRI if there are nerve fiber bundle visual field defects because you cannot presume that drusen optic neuropathy is the whole explanation
- Patients with drusen may develop slowly progressive visual field defects that do not affect visual acuity but may eventually compromise safe driving, therefore…
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Tip: patients should undergo serial visual field testing to exclude the development of defects that would make driving unsafe
- Patients may develop sudden vision loss from peripapillary subretinal hemorrhage
- Advise patients that future examiners performing ophthalmoscopy may misdiagnose papilledema and initiate unnecessary evaluations