Ophthalmologic features of the common spinocerebellar ataxias

Abstract

The ophthalmologist may be the first to encounter a patient with SCA, and a review of the most common genetic subtypes of this disorder is helpful in diagnosis and management.

Cerebellum and Ocular Motor Control

“…This has been suggested as a cause of opsoclonus (e.g., in paraneoplastic and other immune mediated syndromes; Wong et al, 2001; Helmchen et al, 2003). Dysfunction of the FOR might also lead to saccadic intrusions, as occur in spinocerebellar ataxia syndromes (Pula et al, 2010). Saccadic intrusions and hypermetric saccades occur in SCASI (spinocerebellar ataxia with saccadic intrusions) in which patients also have peripheral neuropathy.…”

Oculomotor deficits in spinocerebellar ataxia type 3: Potential biomarkers of preclinical detection and disease progression

“…Because of the frequent involvement of the cerebellum and brainstem, oculomotor disturbances, including square‐wave jerk (SWJ), gaze‐evoked nystagmus (GEN), impaired smooth pursuit eye movement (SPEM), and dysmetric saccade, are main characteristics of SCA3, some of which have also been recognized as distinguishing features between SCA3 and other SCAs . A growing body of evidence indicates that the preclinical stage of SCAs is already characterized by detectable oculomotor signs, including slowing of saccade in preclinical stage of SCA2 and SCA7, saccade dysmetria in SCA6, and impaired SPEM in SCA17 .…”

Novel Maculopathy in Patients With Spinocerebellar Ataxia Type 1 Autofluorescence Findings and Functional Characteristics

“…Ophthalmic examination findings associated with moyamoya syndrome include isolated morning glory disc anomaly; a syndrome consisting of morning glory disc anomaly, optic nerve hypoplasia, chorioretinal coloboma, sphenopharyngeal meningoencephalocele, and midline cranial defects 2 ; anterior ischemic optic neuropathy 3 ; ocular ischemic syndrome, manifesting with neovascularization of the optic disc, venous dilation and beading, neovascularization of the retina vessels, and vitreous hemorrhage …”

“…1 The number of known SCA subtypes continues to grow and currently includes at least 27 subtypes, 2 numbered in the order of discovery of the defective gene. Spinocerebellar ataxia type 1 (SCA1) typically presents in the fourth decade (age range, 4-74 years) with dysarthria, handwriting difficulties, and limb ataxia.…”