Walsh & Hoyt: Secondary Causes

IIH is a diagnosis of exclusion that occurs primarily in young obese women, and occasionally obese men, with no evidence of any underlying disease. The PTC syndrome may be associated with a number of different conditions. The suspicion of a secondary cause is heightened in prepubertal children, men, nonobese women and otherwise typical patients with rapidly progressive visual loss that does not respond to treatment. The secondary causes of PTC include: (a) obstruction or impairment of cerebral venous drainage; (b) endocrine and metabolic dysfunction; (c) exposure to exogenous drugs and other substances; (d) withdrawal of certain drugs; and (e) systemic illnesses. It is important to realize that, although many conditions have been reported with PTC, relatively few are likely to be true associations. Tables 5.35.6 list associated conditions; the best-substantiated and most frequently observed ones are discussed in the text.