**6. Dementia**

INPH patients have subcortical frontal dysexecutive syndrome, manifesting as memory impairment, decreased attention, impaired planning, slowness of thought, and apathy. The cognitive findings of NPH reflect involvement of the prefrontal brain structures, similar to a subcortical dementia, with executive dysfunction (e.g., slow processing, and difficulty with problem solving) and memory deficits with poor retrieval and relatively intact recognition memory. Delirium is not typical in NPH and implies the presence of a concomitant disorder or medication side effect.

#### **7. Urinary incontinence**

The urological manifestations include frequency, urgency, and urge incontinence. In a series of 41 patients with possible iNPH, 95% patients had urodynamic evidence of detrusor overactivity [12]. Bladder manifestations in NPH have been attributed to the involvement of sacral fibers of corticospinal pathway. Patients

**59**

**Figure 2.**

**Figure 1.**

*index > 0.3).*

*Normal Pressure Hydrocephalus*

suspected NPH.

**8. Imaging**

*DOI: http://dx.doi.org/10.5772/intechopen.92058*

are usually aware of the urinary urge and are concerned about their incontinence. Incontinence without awareness of urinary urge or that one's clothes are wet is not a feature of NPH. Patients or family should be asked about the use of incontinence pads or undergarments, as occasionally they do not consider the patient to be incontinent if the urine is contained by the pads or undergarments. As bladder symptoms are common in elderly patients, other causes are frequently present in patients with

The differential diagnosis of NPH other non-treatable causes of dementias and degenerative disorders is extremely for proper selection of potential candidates for CSF diversion. No brain imaging studies are sufficient to diagnose INPH; however ventricular enlargement with appropriate symptoms is necessary to establish a diagnosis of NPH. Combination of imaging modalities and correlation with clinical findings shall help to make a diagnosis of NPH [2]. Evans' index 0.3 or greater suggests significant ventriculomegaly (**Figures 1** and **2**) [19]. Other imaging features include:

*CT brain of a patient with INPH showing ventriculomegaly without significant cortical atrophy (Evan's* 

*CT brain of a patient with INPH showing increased bicaudate ratio > 0.25.*

### *Normal Pressure Hydrocephalus DOI: http://dx.doi.org/10.5772/intechopen.92058*

are usually aware of the urinary urge and are concerned about their incontinence. Incontinence without awareness of urinary urge or that one's clothes are wet is not a feature of NPH. Patients or family should be asked about the use of incontinence pads or undergarments, as occasionally they do not consider the patient to be incontinent if the urine is contained by the pads or undergarments. As bladder symptoms are common in elderly patients, other causes are frequently present in patients with suspected NPH.
