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Age dependent normal horizontal VOR gain of head impulse test as measured with video-oculography.

Mossman B, Mossman S, Purdie G, Schneider E - J Otolaryngol Head Neck Surg (2015)

Bottom Line: Although normative data is available for VOR gain with video-oculography, most normal studies in general include small numbers of subjects and do not include analysis of variation of VOR gain with age.A non-physiologically high horizontal HVOR velocity gain was found to occur in tests where passive HITs were predictable in direction and time and where target distance was below 0.70 m.Normative data with respect to HVOR velocity gain decreases slightly with age, but with careful attention to methodology the 2 SD lower limit of normal is relatively robust across a wide age range and into the eighth decade, without requirement for adjustment with age.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, Wellington Hospital, Riddiford Street, Private Bag 7902, Wellington South, Wellington, New Zealand. mossman.benjamin@gmail.com.

ABSTRACT

Background: The head impulse test (HIT) is a recognised clinical sign of the high frequency vestibulo-ocular reflex (VOR), which can be quantified with video-oculography. This measures the VOR gain as the ratio of angular eye velocity to angular head velocity. Although normative data is available for VOR gain with video-oculography, most normal studies in general include small numbers of subjects and do not include analysis of variation of VOR gain with age. The purpose of our study was to establish normative data across 60 control subjects aged 20 to 80 years to represent a population distribution.

Methods: Sixty control subjects without any current or previous form of brain disorder or vertigo participated in this study and form the basis for future comparison to patients with vestibular lesions. The relationship between the horizontal vestibulo-ocular reflex (HVOR) velocity gain and age was analysed using a mixed regression model with a random effect for subjects. Differences in testing technique were assessed to ensure reliability in results.

Results: The mean HVOR velocity gain of 60 normal subjects was 0.97 (SD = 0.09) at 80 ms and 0.94 (SD = 0.10) at 60 ms. The 2 SD lower limit of normal HVOR velocity gain was 0.79 at 80 ms and 0.75 at 60 ms. No HVOR velocity gain fell below 0.76 and 0.65 at 80 ms and 60 ms respectively. The HVOR velocity gain declined by 0.012 and 0.017 per decade as age increased at 80 ms and 60 ms respectively. A non-physiologically high horizontal HVOR velocity gain was found to occur in tests where passive HITs were predictable in direction and time and where target distance was below 0.70 m.

Conclusions: Normative data with respect to HVOR velocity gain decreases slightly with age, but with careful attention to methodology the 2 SD lower limit of normal is relatively robust across a wide age range and into the eighth decade, without requirement for adjustment with age.

No MeSH data available.


Related in: MedlinePlus

a: Normal HVOR velocity gain at 80 ms decline with age. HVOR velocity gain was found to decline by 0.012 per decade with increasing age (95 % CI 0.001 to 0.022; p = 0.028). HVOR velocity gain is the ratio of angular eye velocity to angular head velocity. b: Normal HVOR velocity gain at 60 ms decline with age. HVOR velocity gain was found to decline by 0.017 per decade with increasing age 95 %CI 0.006 – 0.029; p = 0.005). HVOR velocity gain is the ratio of angular eye velocity to angular head velocity
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Fig5: a: Normal HVOR velocity gain at 80 ms decline with age. HVOR velocity gain was found to decline by 0.012 per decade with increasing age (95 % CI 0.001 to 0.022; p = 0.028). HVOR velocity gain is the ratio of angular eye velocity to angular head velocity. b: Normal HVOR velocity gain at 60 ms decline with age. HVOR velocity gain was found to decline by 0.017 per decade with increasing age 95 %CI 0.006 – 0.029; p = 0.005). HVOR velocity gain is the ratio of angular eye velocity to angular head velocity

Mentions: The HVOR velocity gain at 80 ms declined by 0.012 (95 % CI 0.001 – 0.022) per decade as age increased (p = 0.028), and at 60 ms declined by 0.017 (95 % CI 0.006 – 0.029) per decade as age increased (p = 0.005) (Fig. 5a, b). In patients younger than 70 years, the HVOR velocity gain was always above 0.80 at 80 ms and always above 0.76 at 60 ms.Fig. 5


Age dependent normal horizontal VOR gain of head impulse test as measured with video-oculography.

Mossman B, Mossman S, Purdie G, Schneider E - J Otolaryngol Head Neck Surg (2015)

a: Normal HVOR velocity gain at 80 ms decline with age. HVOR velocity gain was found to decline by 0.012 per decade with increasing age (95 % CI 0.001 to 0.022; p = 0.028). HVOR velocity gain is the ratio of angular eye velocity to angular head velocity. b: Normal HVOR velocity gain at 60 ms decline with age. HVOR velocity gain was found to decline by 0.017 per decade with increasing age 95 %CI 0.006 – 0.029; p = 0.005). HVOR velocity gain is the ratio of angular eye velocity to angular head velocity
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4506627&req=5

Fig5: a: Normal HVOR velocity gain at 80 ms decline with age. HVOR velocity gain was found to decline by 0.012 per decade with increasing age (95 % CI 0.001 to 0.022; p = 0.028). HVOR velocity gain is the ratio of angular eye velocity to angular head velocity. b: Normal HVOR velocity gain at 60 ms decline with age. HVOR velocity gain was found to decline by 0.017 per decade with increasing age 95 %CI 0.006 – 0.029; p = 0.005). HVOR velocity gain is the ratio of angular eye velocity to angular head velocity
Mentions: The HVOR velocity gain at 80 ms declined by 0.012 (95 % CI 0.001 – 0.022) per decade as age increased (p = 0.028), and at 60 ms declined by 0.017 (95 % CI 0.006 – 0.029) per decade as age increased (p = 0.005) (Fig. 5a, b). In patients younger than 70 years, the HVOR velocity gain was always above 0.80 at 80 ms and always above 0.76 at 60 ms.Fig. 5

Bottom Line: Although normative data is available for VOR gain with video-oculography, most normal studies in general include small numbers of subjects and do not include analysis of variation of VOR gain with age.A non-physiologically high horizontal HVOR velocity gain was found to occur in tests where passive HITs were predictable in direction and time and where target distance was below 0.70 m.Normative data with respect to HVOR velocity gain decreases slightly with age, but with careful attention to methodology the 2 SD lower limit of normal is relatively robust across a wide age range and into the eighth decade, without requirement for adjustment with age.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, Wellington Hospital, Riddiford Street, Private Bag 7902, Wellington South, Wellington, New Zealand. mossman.benjamin@gmail.com.

ABSTRACT

Background: The head impulse test (HIT) is a recognised clinical sign of the high frequency vestibulo-ocular reflex (VOR), which can be quantified with video-oculography. This measures the VOR gain as the ratio of angular eye velocity to angular head velocity. Although normative data is available for VOR gain with video-oculography, most normal studies in general include small numbers of subjects and do not include analysis of variation of VOR gain with age. The purpose of our study was to establish normative data across 60 control subjects aged 20 to 80 years to represent a population distribution.

Methods: Sixty control subjects without any current or previous form of brain disorder or vertigo participated in this study and form the basis for future comparison to patients with vestibular lesions. The relationship between the horizontal vestibulo-ocular reflex (HVOR) velocity gain and age was analysed using a mixed regression model with a random effect for subjects. Differences in testing technique were assessed to ensure reliability in results.

Results: The mean HVOR velocity gain of 60 normal subjects was 0.97 (SD = 0.09) at 80 ms and 0.94 (SD = 0.10) at 60 ms. The 2 SD lower limit of normal HVOR velocity gain was 0.79 at 80 ms and 0.75 at 60 ms. No HVOR velocity gain fell below 0.76 and 0.65 at 80 ms and 60 ms respectively. The HVOR velocity gain declined by 0.012 and 0.017 per decade as age increased at 80 ms and 60 ms respectively. A non-physiologically high horizontal HVOR velocity gain was found to occur in tests where passive HITs were predictable in direction and time and where target distance was below 0.70 m.

Conclusions: Normative data with respect to HVOR velocity gain decreases slightly with age, but with careful attention to methodology the 2 SD lower limit of normal is relatively robust across a wide age range and into the eighth decade, without requirement for adjustment with age.

No MeSH data available.


Related in: MedlinePlus