Methods:
According to clinical features, assessment for the cause of cognitive
decline and gait difficulty was performed. The brain CT scan showed
significant ventriculomegaly (i.e. Evans index of 0.37) including third
and fourth ventricles which was disproportionate to the amount of
cortical atrophy (Figure 1). The other laboratory tests were in normal
range including complete blood count, thyroid function tests, HIV
antibody titer and vitamin B12 level.
The clinical and imaging features were in favor of probable iNPH.
Consequently, lumbar tap was performed two times that revealed
significant change in gait after removal of approximately 30 ml of CSF.
After the first trial of tap test, he can walk independently, which was
more pronounced after the second trial. The speed and cadence of gait
after first and second trial of tap test were noted in Table 1. The
analyses of CSF markers were in normal range but the opening pressure
was slightly elevated in two times of four lumbar puncture (Table 1).