Fig. 2

Serial Tap Test Procedure. LP (Lumbar puncture), INPH group (Idiopathic normal pressure hydrocephalus). BLP: step before lumbar punctures; ALP1: step after the first lumbar puncture; post ALP2: step after the second lumbar puncture. * Scores from 1^st, 4^st and 7^st INPH group steps were compared with 1^st Control group step (Table 3). * Scores from 1^st, 4^st and 7^st INPH group steps were compared for detecting changes along the procedure in the INPH group (Table 4). ** See [16] for further details about gait assessment. *** Quincke spinal needle 22G with metallic stylet introduced at an angle of 60º with the skin at the midline. A spinal manometry was conducted to assess the opening pressure