LOINCActive

LOINC Code 28993-4: Left cornea Longitudinal radius by Keratometry

28993-4 is a LOINC code used to identify Left cornea Longitudinal radius by Keratometry in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Longitudinal radius. It is commonly used with the system or sample type Cornea.left.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Longitudinal radius. It is commonly used with the system or sample type Cornea.left.

When is it used?

  • Used in lab systems, EHRs, and clinical data exchange.
  • May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
  • Status: ACTIVE
  • Method: Keratometry

What it does not mean

  • The code identifies the observation or test, not the actual result.

Key facts

  • Left cornea Longitudinal radius by Keratometry
  • Longitudinal radius
  • by KM; Corneal; EYE; EYE.REFRACTION; L; L cornea; Length; Longit radius; LT; Ophthalmology; Ophthalmometer; Ophtho; Ophthy; Point in time; QNT; Quan; Quant; Quantitative; Random; Upper extremity

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

Left cornea Longitudinal radius by KeratometryL cornea Longit radius by KMLongitudinal radiusEYE.REFRACTIONLenPtCornea.left

Frequently asked questions

Code details

Code28993-4
SystemLOINC
Display nameLeft cornea Longitudinal radius by Keratometry
DescriptionLongitudinal radius
Short nameL cornea Longit radius by KM
ComponentLongitudinal radius
PropertyLen
TimingPt
System (specimen)Cornea.left
ScaleQn
MethodKeratometry
ClassEYE.REFRACTION
Example unitsmm
StatusACTIVE

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.00
Last changed2.68

Part names

Longitudinal radiusLenPtCornea.leftQnKeratometryLengthPoint in time (spot)Left cornea

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.

LOINC Code 28993-4 | HealthAssure