Metamorphopsia: Symptoms, Causes, Treatment

What are the symptoms of metamorphopsia?

Metamorphopsia is a visual distortion where objects appear warped, bent, or misshapen. It can affect both near and distant vision. Common symptoms include:

• Straight lines appear wavy or curved: A hallmark symptom is the perception that straight lines, such as door frames or the lines on graph paper, appear distorted.
• Objects appear smaller or larger than they are: Known as micropsia (objects appear smaller) or macropsia (objects appear larger).
• Distorted shapes: Objects may seem stretched, compressed, or otherwise abnormally shaped.
• Difficulty with depth perception: The ability to judge the relative distance of objects may be impaired.
• Blurry or patchy vision: Areas of vision may appear blurred or missing, often accompanying distortion.

Metamorphopsia is often associated with eye conditions like macular degeneration, retinal detachment, or macular edema, and may also be caused by brain disorders affecting visual processing.

What are the causes of metamorphopsia?

Metamorphopsia is typically caused by conditions that affect the retina, particularly the macula, or by issues in the brain that interfere with visual processing. Common causes include:

• Age-related macular degeneration (AMD): A leading cause of metamorphopsia, where the central part of the retina deteriorates, affecting the perception of shapes and lines.
• Macular edema: Swelling in the macula due to fluid accumulation can distort vision.
• Macular hole: A small break in the macula that leads to distorted central vision.
• Retinal detachment: When the retina pulls away from the back of the eye, it can cause visual distortion.
• Epiretinal membrane (macular pucker): A thin layer of scar tissue on the macula that can distort vision.
• Diabetic retinopathy: Damage to the retinal blood vessels from diabetes, which can affect the macula and lead to distortion.
• Trauma to the eye: Injuries that affect the retina or macula can cause visual distortions.
• Neurological disorders: Brain conditions affecting visual pathways, such as strokes, tumors, or multiple sclerosis, may lead to metamorphopsia.

Early detection and treatment of the underlying cause are important for preventing permanent vision loss.

What is the treatment for metamorphopsia?

The treatment for metamorphopsia depends on its underlying cause, as it is a symptom rather than a standalone condition. Common treatments include:

• Age-related macular degeneration (AMD):
• For wet AMD, treatments include anti-VEGF injections (such as ranibizumab or bevacizumab) to reduce abnormal blood vessel growth.
• For dry AMD, there is no cure, but certain vitamins (AREDS formula) may slow progression.
• Macular edema:
• Anti-VEGF injections or steroid injections may reduce swelling in the macula.
• Laser therapy can sometimes be used for macular edema caused by diabetic retinopathy or vein occlusions.
• Macular hole:
• Vitrectomy surgery is commonly performed to close the macular hole and improve visual distortion.
• Epiretinal membrane (macular pucker):
• Surgery called membrane peeling (part of vitrectomy) can be done to remove the scar tissue on the macula.
• Retinal detachment:
• Immediate surgical intervention, such as vitrectomy, scleral buckle, or pneumatic retinopexy, is required to reattach the retina.
• Diabetic retinopathy:
• Treatments include controlling blood sugar, laser surgery, anti-VEGF injections, or vitrectomy to address macular edema or other retinal changes.
• Neurological causes:
• If metamorphopsia is caused by a neurological condition, treatment focuses on managing the underlying issue, such as stroke rehabilitation, brain tumor removal, or controlling multiple sclerosis.

Early intervention can improve outcomes, especially if the underlying condition is addressed promptly. For some cases, specialized low-vision aids may help people manage visual distortions.