From the Guidelines
Color stereophotography is the most important type of photograph for documenting optic nerve drusen, as it provides a clear and detailed image of the optic nerve head and can help identify signs of glaucomatous damage, such as optic disc hemorrhages and thinning of the neuroretinal rim. According to the primary open-angle glaucoma suspect preferred practice pattern 1, color stereophotography is an accepted method for documenting qualitative ONH appearance as well as disc hemorrhages. This is particularly important for optic nerve drusen, as they can cause visual field defects and, rarely, vision loss due to compression of nerve fibers or vascular complications.
The use of color stereophotography is supported by the fact that it provides a detailed image of the optic nerve head, allowing for the identification of signs of glaucomatous damage, such as vertical elongation of the optic nerve cup, enlargement of the optic nerve cup, and diffuse or focal narrowing of the neuroretinal rim 1. Additionally, color stereophotography can help identify optic disc hemorrhages, which are a sign of ongoing optic nerve damage in patients with glaucoma 1.
Other imaging techniques, such as optical coherence tomography (OCT) and scanning laser polarimetry, can provide complementary information about the optic nerve and retinal nerve fiber layer, but color stereophotography remains the most important type of photograph for documenting optic nerve drusen 1.
Some key points to consider when using color stereophotography to document optic nerve drusen include:
- The importance of using magnified stereoscopic visualization to examine the optic nerve head 1
- The need to document the appearance of the optic nerve head and retinal nerve fiber layer 1
- The use of color stereophotography to identify signs of glaucomatous damage, such as optic disc hemorrhages and thinning of the neuroretinal rim 1
- The importance of interpreting the results of color stereophotography in the context of the clinical examination and other supplementary tests 1
From the Research
Types of Photographs for Optic Nerve Drusen
The following types of photographs are important for optic nerve drusen:
- Fundus photography: used to confirm visible drusen of the optic disc 2
- Fundus autofluorescence: used to detect autofluorescence of optic disc drusen 3, 4
- Optical Coherence Tomography (OCT) imaging: used to provide detailed images of optic nerve head drusen, including their size, shape, and location 5, 3, 4
- Optical Coherence Tomography Angiography (OCTA): used to analyze peripapillary vessel density and confirm the diagnosis of optic nerve head drusen 6
Characteristics of Optic Nerve Drusen in Photographs
Optic nerve drusen can appear as:
- Ovoid regions of lower reflectivity bordered by hyperreflective material on OCT images 3
- Scattered spots with high reflectivity casting a shadow underneath on Spectralis OCT images 4
- Autofluorescent deposits on fundus autofluorescence images 3, 4
Diagnostic Yield of Different Imaging Techniques
The diagnostic yield of different imaging techniques for optic nerve drusen is:
- B-scan echography: highest diagnostic yield, especially for buried drusen 2
- OCT imaging: high diagnostic yield, especially for detailed imaging of optic nerve head drusen 5, 3, 4
- Fundus autofluorescence: moderate diagnostic yield, especially for detecting autofluorescence of optic disc drusen 3, 4
- CT scans: low diagnostic yield, but useful for excluding intracranial mass lesions 2