Understanding Leber’s Hereditary Optic Neuropathy Diagnosis | idebenone.org

Leber’s hereditary optic neuropathy (LHON) diagnosis plays a crucial role in identifying and managing this rare mitochondrial genetic condition that primarily affects vision. Early and accurate diagnosis can support better outcomes and precise treatment planning, including the use of idebenone — a medication studied for LHON patients.

LHON typically presents with sudden, painless vision loss in one eye, followed by the other eye within weeks to months. Because symptoms may mimic other optic nerve disorders, healthcare professionals rely on a structured diagnostic approach. The first essential step is a comprehensive eye examination, including assessment of visual acuity, color vision, and visual field testing. These tests help determine the degree and pattern of vision loss, often revealing central or cecocentral scotomas — characteristic signs of LHON.

In addition to clinical evaluation, optical coherence tomography (OCT) provides high-resolution imaging of the retinal nerve fiber layer. Thinning of this layer is frequently observed in LHON patients and can help differentiate LHON from other optic neuropathies. Similarly, visual evoked potentials (VEPs) measure electrical responses in the brain following visual stimulation and may show delayed or diminished signals in affected individuals, reflecting dysfunction of the visual pathways.

However, the definitive confirmation comes from genetic testing, which identifies mutations in mitochondrial DNA. The most common mutations associated with LHON are at positions 11778, 14484, and 3460. A positive genetic test confirms the diagnosis and is essential for counseling family members since LHON is maternally inherited. Many individuals with a family history of LHON undergo genetic screening even before symptoms appear. Visit us: https://idebenone.org/