Pendular nystagmus comprises oscillations that are approximately equal in rate in two directions; they may be horizontal or vertical.

1. Albinism in which the macula does not develop

2. Aniridia (see p. 364-365)

3. Bilateral chorioretinal lesions involving the macula in early infancy (congenital toxoplasmosis)

4. Brainstem or cerebellar dysfunction

*5. Congenital-cause unknown, may be inherited as autosomal dominant recessive or X-linked recessive trait; not infrequently associated with astigmatism and convergent strabismus

*6. Congenital cataracts

7. Congenital glaucoma

8. Corneal scars

9. Demyelinating disease

10. High myopia of early life

11. Internuclear ophthalmoplegia

12. Laurence-Moon-Bardet-Biedl syndrome (retinitis pigmentosa-polydactyly-adiposogenital syndrome)

13. Leber congenital amaurosis

14. Monocular or binocular visual deprivation

15. Optic nerve hypoplasia, coloboma

*16. Total color blindness (monochromatism)

17. Work in poor illuminations (e.g., mining) (rare)

Cogan DG. Neurology of the ocular muscles, 4th ed. Springfield, IL: Charles C Thomas, 1978.

Roy FH. Ocular syndrome and systemic diseases, 3rd ed. Philadelphia: Lippincott Williams & Wilkins, 2002.

Walsh FB, Hoyt WF. Clinical neuro-ophthalmology, 4th ed. Baltimore: Williams & Wilkins, 1985.