Version 2.78

Part Descriptions

LP73686-5   Visual acuity
When discussing visual acuity, such as 20/40, the numerator is the testing distance. In the US, 20 is measured in feet. In the metric system, the testing distance is measured in meters. Normal visual acuity is commonly referred to as 20/20 vision and the metric equivalent is 6/6 vision.

The denominator is also a distance - the distance at which the size of the tested letter would subtend an arc of 5 minutes; what changes is the size of the letters and the distance at which the letters subtend that 5 minutes of angle. A letter of the size on the 20/40 line of an eye chart would be able to be seen by a patient with normal (20/20) vision at a testing distance of 40 feet, but for a patient with reduced vision (e.g. 20/40) the letter would need to be moved closer (to 20 feet) in order to be seen. When reading an eyechart in an ophthalmology exam room, mirrors are used to simulate a 20 foot testing distance (as the room is typically much shorter than 20 feet in length).

Visual acuity is expressed as 20/20, 20/40 up to about 20/800. Vision worse than that is often expressed qualitatively as:
CF- Count Fingers
HM- Hand Motion
LP- Light Perception
NLP- No Light Perception Source: Regenstrief Help

LP73686-5   Visual acuity
Uncorrected visual acuity is a measurement of clearness of vision while the patient is not using refractive correction. Best corrected visual acuity is acuity measurement using corrective lenses, if usually worn. Visual acuity measured using a Snellen Eye Chart is reported with a numerator of the standard testing distance of 20 and a denominator indicating the distance at which strokes of the smallest letter size viewable subtend at 1 minute of arc. (e.g., 20/10: with a standard testing distance of 20 feet, the strokes of the smallest letter size viewable would subtend 1 minute of arc at 10 feet, or as more commonly explained, what the patient can see at 20 feet, the average population can see at 10 feet). If unable to read letters on a testing chart, visual acuity is described as ranging from ability to count fingers, recognize hand motion, perceive bright light, or unable to perceive light. Source: Regenstrief LOINC

Fully-Specified Name

Component
Visual acuity^uncorrected
Property
LenRto
Time
Pt
System
Eye.left
Scale
Qn
Method

Additional Names

Short Name
L eye VA--uncorr

Basic Attributes

Class
EYE.REFRACTION
Type
Clinical
First Released
Version 2.72
Last Updated
Version 2.72
Order vs. Observation
Observation

Member of these Panels

LOINC Long Common Name
98497-1 Visual acuity panel

Language Variants Get Info

Tag Language Translation
it-IT Italian (Italy) Acuità visiva^Incorretto:LenRto:Pt:Occhio.sinistro:Qn:
Synonyms: Occhio Occhio Sinistro Oftalmologia - rifrazione Punto nel tempo (episodio) Rapporto lunghezze
zh-CN Chinese (China) 视力^未经校正的:长度比率:时间点:眼睛.左侧:定量型:
Synonyms: L LT Refraction measurements;屈光度指标;屈光度测量指标;眼.屈光度指标;眼.屈光度测量指标;眼科.屈光度指标;眼科.屈光度测量指标;眼科学与视力测定变量.屈光度指标;眼科学与验光变量.屈光度指标;眼科学与验光变量.屈光度测量指标;眼科学与验光指标.屈光度指标;眼科学与验光指标.屈光度测量指标 可用数量表示的;定量性;数值型;数量型;连续数值型标尺 向左 向左侧 左 左侧（Left，LT，L） 左侧眼睛;左眼 左向 左边 时刻;随机;随意;瞬间 未经改正的;未经矫正的;未修改的;未调整的;未修正的;未改正的;没有经过校正的 目;眼;眼部 眼;眼睛;眼科;眼科学与验光变量;眼科学与验光指标 视觉 视觉敏锐度 长度比

Example Units

Unit Source
[ft_us]/[ft_us] Example UCUM Units

LOINC Terminology Service (API) using HL7® FHIR® Get Info

CodeSystem lookup
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=98498-9