Normal-pressure hydrocephalus classification

Level II ¹⁾: Since strict diagnostic criteria cannot be formulated for NPH because of a lack of knowledge of the underlying pathophysiology at this time, it is recommended that the diagnosis be made in terms of Probable, Possible, and Unlikely NPH

The development of guidelines in 2005 was made difficult because systematic studies of INPH and patient numbers were few. It was decided to maintain the classification of NPH into two major categories, INPH and those of known cause (secondary NPH).

Many studies “mixed” these classifications, and as a result, they could not be used in the evidentiary tables. Despite these problems, evidence-based guidelines were developed, and it is hoped that they will be useful in guiding clinical management of the INPH patient ²⁾.

Primary or Idiopathic normal pressure hydrocephalus (iNPH).

Secondary normal pressure hydrocephalus.

¹⁾

Relkin N, Marmarou A, Klinge P, et al. INPH Guidelines, Part II: Diagnosing idiopathic normal- pressure hydrocephalus. Neurosurgery. 2005; 57: S2–4 to 16

²⁾

Marmarou A, Bergsneider M, Relkin N, Klinge P, Black PM. Development of guidelines for idiopathic normal-pressure hydrocephalus: introduction. Neurosurgery. 2005 Sep;57(3 Suppl):S1-3; discussion ii-v. PubMed PMID: 16160424.