The toxic optic neuropathies (TON) are caused by a widely varied group of insults that may include chemicals, drugs, nutritional defects, and vaccines ( Box 46.1 ). The goal of…

Introduction Nystagmus is defined as a rhythmic oscillation of the eyes. The term “nystagmus” is a transliteration of a Greek word for “drowsy head-nodding movements,” since the jerky eye movements…

Introduction Ischemic optic neuropathy refers to a group of conditions in which damage to the optic nerve is presumed to be secondary to ischemia of the optic nerve head (anterior…

Clinical background Optic atrophy can be considered the wasting of a once-healthy optic nerve. This definition excludes conditions associated with optic nerve dysplasia, hypoplasia, or aplasia in which the optic…

Overview Unlike the peripheral nervous system (PNS), in which axonal injury leads to regeneration, injury to axons of central nervous system (CNS) neurons is irreversible, and usually leads to death…

Clinical background Historical development Leber’s hereditary optic neuropathy (LHON) is a maternally inherited disease that presents with sudden or subacute nonsynchronous bilateral vision loss. Males in their second and third…

Clinical background Key symptoms and signs The signs and symptoms of increased intracranial pressure (ICP) are headache, subjective pulse-synchronous bruit, and papilledema ( Box 39.1 ). Papilledema can cause fleeting…

Clinical background Giant cell arteritis (GCA) is a serious and relatively common systemic vasculitis that occurs in adults older than 50 years. The key symptoms and signs of GCA include…

Clinical background Five eye movement systems are utilized to achieve clear vision: (1) saccadic; (2) smooth pursuit; (3) optokinetic; (4) vestibulo-ocular; and (5) vergence. Four systems generate conjugate movements, called…

Overview Intraoperative floppy iris syndrome (IFIS) was first characterized by Chang and Campbell in 2005. It is associated with the use of systemic α-receptor blockers, such as tamsulosin (Flomax), used…