*6.3.1.4 Psychometric hepatic encephalopathy score (PHES)*

It consists of five paper-pencil tests: NCT-A/B, line tracing time (LTT), digit symbol test, and serial-dotting test (SDOT). This battery measures psychomotor speed and precision, visual perception, visuospatial orientation, visual

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impact [90, 91].

*Minimal Hepatic Encephalopathy: Silent Tragedy DOI: http://dx.doi.org/10.5772/intechopen.88231*

mortality in cirrhotic patients [42, 43]**.**

*6.3.1.5 The animal naming test (ANT)*

*6.3.2 Computer-aided psychometric tests*

*6.3.2.1 The critical flicker frequency (CFF)*

numeracy, literacy, and age [89].

*6.3.2.2 Continuous reaction time (CRT) test*

*6.3.2.3 The inhibitory control test (ICT)*

the bedside [85].

minutes [10, 86, 87].

construction, concentration, attention, and memory and can be completed in less than 20 minutes [68]. The results of PHES can be affected by age and education status of patients. A score is defined as the number of standard deviations of the difference between the two values for each test. MHE was diagnosed with the sum of all scores less than or equal to −4 points. Score < −4 suggests the presence of MHE [1, 84]. A simplified form of PHES, developed using only three of the original five tests, can be as good as the PHES in diagnosing [84]. For illiterate patients, the figure connection test has been used as a subtest instead of the number connection test [1]. PHES has a prognostic value for the occurrence of attacks of overt HE and

The ANT (maximum number of animals listed in 1 minute) has recently been developed to predict OHE. ANT is an easy test that has all the required characteristics of simplicity, speed, no cost, and relationship with clinical events to be used routinely for rapid investigation of HE in patients with cirrhosis at the office and at

Numerous current studies have showed that, computerization of psychometric tests could lead to simplification and easy administration in the clinic within a few

CFF test is a psychophysiological tool that studies the frequency at which a fused light (presented from 60 Hz downward) appears to be flickering to the observer. Similarly, the general arousal of the patient is measured. Earlier studies have shown a reduction in its performance with worsening cognition and improvement after therapy. The CFF test needs numerous trials, intact binocular vision, absence of red-green blindness, and specialized equipment [15]. CFF predicts the first episode of OHE in cirrhotic patients who had never experienced OHE, and predicts mortality risk [88]. CFF test has many advantages, for example, easy administration, application by a non-specialist personal, and results that are independent of

This test assesses the motor reaction time by having the patient press a button in response to auditory stimuli (through headphones). The most important test result is the CRT index, which measures the stability of the reaction times. The test result can differentiate between organic and metabolic brain impairment. The test is not affected by the patient's age, gender with no learning or tiring

It is a computerized test of response inhibition and working. The ICT requires highly functional patients (**Figure 6**). The ICT can be done using a laptop and is analyzed using an automatic computerized system that significantly improves the

#### *Minimal Hepatic Encephalopathy: Silent Tragedy DOI: http://dx.doi.org/10.5772/intechopen.88231*

*Liver Disease and Surgery*

**Figure 4.**

**Figure 5.** *Digit symbol test.*

*Number connection tests-B.*

*6.3.1.2 Digit symbol test DST*

*6.3.1.3 Block design test*

from the age-matched normal values [79].

Nine fixed pairs of numbers and symbols are present at the top of the test sheet.

This test recorded speed and accuracy. The task is to take 6–9 blocks that have all white sides, all red sides, and red-and-white sides followed by arranging them

It consists of five paper-pencil tests: NCT-A/B, line tracing time (LTT), digit symbol test, and serial-dotting test (SDOT). This battery measures psychomotor speed and precision, visual perception, visuospatial orientation, visual

according to a pattern formed by examiner or shown on a card [83].

*6.3.1.4 Psychometric hepatic encephalopathy score (PHES)*

The patient is given a series of double boxes with a number given in the upper part. The target is to draw a symbol related to this number into the lower part of the boxes. The test result is the number of boxes correctly filled in 90 s (**Figure 5**). Pathological test results indicate a deficit in visuoconstructive abilities. [82]. DST will be considered abnormal when the test scores are less than the mean − 2 SDs

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construction, concentration, attention, and memory and can be completed in less than 20 minutes [68]. The results of PHES can be affected by age and education status of patients. A score is defined as the number of standard deviations of the difference between the two values for each test. MHE was diagnosed with the sum of all scores less than or equal to −4 points. Score < −4 suggests the presence of MHE [1, 84]. A simplified form of PHES, developed using only three of the original five tests, can be as good as the PHES in diagnosing [84]. For illiterate patients, the figure connection test has been used as a subtest instead of the number connection test [1]. PHES has a prognostic value for the occurrence of attacks of overt HE and mortality in cirrhotic patients [42, 43]**.**

### *6.3.1.5 The animal naming test (ANT)*

The ANT (maximum number of animals listed in 1 minute) has recently been developed to predict OHE. ANT is an easy test that has all the required characteristics of simplicity, speed, no cost, and relationship with clinical events to be used routinely for rapid investigation of HE in patients with cirrhosis at the office and at the bedside [85].
