Question

A 70-year-old male presents with central unilateral metamorphopsia. Detail the diagnostic tools and management options.

Hint:

OCT and fluorescein angiography are key diagnostic tools in evaluating macular conditions such as AMD, diabetic retinopathy, and macular edema.

Answer 1

Step 1: Diagnostic Tools for Central Unilateral Metamorphopsia.
To evaluate a patient with central unilateral metamorphopsia, the following diagnostic tools are essential:
(1) Visual Acuity Testing:
- A standard Snellen chart is used to assess the sharpness of vision and detect any decrease in visual acuity.
(2) Amsler Grid Test:
- The Amsler grid is a simple test used to detect metamorphopsia by asking the patient to focus on the central dot and report any distortion in the grid lines. It is a key tool for evaluating conditions like AMD or macular edema.
(3) Fundus Examination (Dilate:
- A thorough dilated fundus exam allows the physician to inspect the retina, macula, and optic disc for any abnormalities such as drusen, retinal hemorrhages, exudates, or neovascularization.
(4) Optical Coherence Tomography (OCT):
- OCT provides detailed cross-sectional images of the retina, allowing for the detection of macular edema, macular holes, epiretinal membranes, and neovascularization in conditions like AMD and diabetic retinopathy.
(5) Fluorescein Angiography (F:
- FA is used to identify choroidal neovascularization and assess the presence of leakage in wet AMD or other vascular retinal conditions. It can also identify areas of retinal ischemia in cases like retinal vein occlusion.
(6) Fundus Autofluorescence (FAF):
- FAF can highlight areas of retinal degeneration and is useful in diagnosing AMD and macular dystrophies.
Step 2: Management Options for Central Unilateral Metamorphopsia.
The management of central unilateral metamorphopsia depends on the underlying diagnosis. Treatment options for common conditions include:
(1) Age-Related Macular Degeneration (AM:
- Anti-VEGF Injections: For wet AMD, anti-vascular endothelial growth factor (VEGF) injections like bevacizumab, ranibizumab, or aflibercept are used to reduce neovascularization and macular edema.
- Photodynamic Therapy (PDT): For certain types of AMD, PDT may be used to treat abnormal blood vessels.
- Nutritional Supplements: For dry AMD, AREDS2 supplements (vitamins C and E, zinc, lutein, and zeaxanthin) may help slow progression.
(2) Macular Edema:
- Steroid Injections or Implants: Intravitreal steroids (e.g., dexamethasone implant) can be used for macular edema, especially in cases related to diabetic retinopathy or retinal vein occlusion.
- Anti-VEGF Therapy: Similar to AMD, anti-VEGF agents can be used for macular edema associated with diabetic retinopathy or retinal vein occlusion.
(3) Macular Hole:
- Vitrectomy Surgery: Surgical treatment, including vitrectomy and internal limiting membrane peeling, may be required for large or symptomatic macular holes.
(4) Epiretinal Membrane (ERM):
- Vitrectomy: If the ERM causes significant vision problems or distortion, vitrectomy surgery with membrane peeling is the treatment of choice.
(5) Central Serous Retinopathy (CSR):
- Observation: In many cases, CSR resolves spontaneously. However, if persistent, laser therapy or photodynamic therapy may be considered.