Leber hereditary optic neuropathy (LHON) is one of the most common inherited optic neuropathies causing bilateral central vision loss. The disorder results from point mutations in mitochondrial DNA and subsequent mitochondrial dysfunction. The primary cell type that is lost in LHON is the retinal ganglion cell, which is highly susceptible to disrupted ATP production and oxidative stress. Inheritance of LHON follows that of mitochondrial genetics, and it has a highly variable clinical phenotype, as other genetic and environmental factors also play a role. Although LHON usually presents with isolated vision loss, some patients suffer other neurological sequelae. For ill-defined reasons, male LHON mutation carriers are more affected than females. Most LHON patients remain legally blind, but a small proportion can experience spontaneous partial recovery, often within the first year of symptom onset. Unfortunately, at this time there are no established curative interventions and treatment is largely supportive. Patients should be offered low vision services and counseled on mitigating risk factors for additional vision loss, such as smoking and consuming alcohol. Encouraging treatments currently undergoing investigation includes ubiquinone analogs, such as idebenone, as well as gene therapy and stem cells to restore ATP synthesis and provide neuroprotection to surviving retinal ganglion cells.
12 April 2016 in Current Neurology and Neuroscience Reports
Anisocoria is a finding seen on a daily basis in nearly every eye clinic. Although often benign, it can also represent the sole sign of a life-threatening disease making an up-to-date understanding of pathophysiology and diagnosis essential for anyone practicing medicine. Many aspects of the traditional approach to anisocoria still hold true today, but advancements in imaging technology and changing trends in pharmacologic diagnosis and localization have led many to rethink that approach. In addition, the differential diagnosis for anisocoria continuously expands with identification and improved understanding of causal disease processes. The present article discusses an approach to the classic anisocoria diagnostic algorithm modified by current knowledge from the most recent literature.
Leber hereditary optic neuropathy (LHON) is rarely associated with multiple sclerosis-like features. We present a case of a 65-year-old African American woman with LHON masquerading as neuromyelitis optica (NMO). We highlight the features of the clinical examination and MRI that were suggestive of an alternative diagnosis and review the literature regarding LHON and multiple sclerosis. The diagnosis of LHON should be considered in all cases of acute or subacute bilateral optic neuropathy, including presumed seronegative NMO.
Crohn disease (CD) is primarily considered an inflammatory condition of the small and large intestine although associated extraintestinal inflammation is relatively common. Ocular manifestations are generally localized to the anterior chamber and ocular surface but rarely can involve the posterior pole, orbit, and optic nerve. We report a case of an otherwise healthy 42-year-old man who was diagnosed with CD after presenting with acute vision loss from optic perineuritis.