[Communicating hydrocephalus. Clinical aspects, diagnosis, pathogenesis].

A description of the clinical symptoms of the communicating hydrocephalus (normal-pressure hydrocephalus = NPH) is given: progressive psycho-organic alterations, ataxia, tetraspastic signs, urinary incontinence, without increased intracranial pressure. Diagnosis can be confirmed by use of pneumencephalography, isotope-cisternography and tomography of the brain by use of a water-solubile contrast fluid. Skull radiographs. EEG, testing of liquor and psychological examinations are of less diagnostic value. The illness is the result of a disturbance of liquor resorption and circulation. In this context there is to differentiate between cases of known (Hydrocephalus communicans obstructivus = HCO) and unknown etiology (Hydrocephalus communicans non obstructivus = HCNO). The group of cases with unknown etiology represents the central part of cases of normal-pressure hydrocephalus (NPH). The prognosis after a ventricular shunt-procedure is here worse than in the group of cases with known etiology. For differential diagnosis presenil dementia, cerebrovascular insufficiency, intracranial tumors and reactive and psychotic depressions are to be considered.