Clinical Update on Metamorphopsia: Epidemiology, Diagnosis and Imaging

ABSTRACT

Purpose: To discuss the pathophysiology of metamorphopsia, its characterisation using retinal imaging and methods of assessment of patient symptoms and visual function.

Methods: A literature search of electronic databases was performed

Results: Metamorphopsia has commonly been associated with vitreomacular interface disorders (such as epiretinal membrane) and has also regularly been noted in diseases of the retina and choroid, particularly age-related macular degeneration and central serous chorioretinopathy. Developments in optical coherence tomography retinal imaging have enabled improved imaging of the foveal microstructure and have led to the localisation of the pathophysiology of metamorphopsia within the retinal layers of the macula. Alteration of alignment of inner and outer retinal layers at various retinal loci has been identified using multimodal imaging in patients with metamorphopsia in a range of conditions. Although the Amsler Grid assessment of metamorphopsia is a useful clinical indicator, new emerging methods of metamorphopsia assessment with psychophysical tests such as M-CHARTS and preferential hyperacuity perimetry, have been developed.

Conclusions: It appears that there is a complex relationship between visual acuity and metamorphopsia symptoms that vary between retinal conditions. Although metamorphopsia has traditionally been challenging to measure in the clinic, advances in technology promise more robust, easy-to-use tests. It is possible that home assessment of metamorphopsia, particularly in conditions such as age-related macular degeneration, may help to guide the need for further clinic evaluation and consideration of treatment.

KEYWORDS:

• Optical coherence tomography
• metamorphopsia
• M-CHARTS
• preferential hyperacuity perimetry
• orientation discrimination threshold

Competing interests

All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript.

The contents of this manuscript were in part presented at The Association of Research in Vision and Ophthalmology (ARVO) Annual Meeting Special Interest Group (SIG) in 2019.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethics approval

For this type of study formal consent is not required.

No human subjects or animal subjects were used in this research.

Additional information

Funding

No funding was received for this research.