LOINCActiveObservation

LOINC Code 79778-7: a-wave implicit time Left retina dark-adapted by ERG

79778-7 is a LOINC code used to identify a-wave implicit time Left retina dark-adapted by ERG 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 a-wave implicit time^dark-adapted. It is commonly used with the system or sample type Retina.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 a-wave implicit time^dark-adapted. It is commonly used with the system or sample type Retina.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
  • Order vs observation: Observation
  • Method: Electroretinogram

What it does not mean

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

Key facts

  • a-wave implicit time Left retina dark-adapted by ERG
  • a-wave implicit time^dark-adapted
  • This term was developed in collaboration with the National Institute of Health's National Eye Institute (NEI) as part of an effort to standardize the data elements collected by the National Ophthalmic Disease Genotyping and Phenotyping Network (eyeGENE).
  • Atrial wave; a-wave impl time; ERG; EYE; EYE.ERG; EYE.ERG.NEI; L; L ret; LT; Ophthalmology; Ophtho; Ophthy; Point in time; QNT; Quan; Quant; Quantitative; Random

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

a-wave implicit time Left retina dark-adapted by ERGa-wave impl time L ret dark-adapt ERGa-wave implicit time^dark-adaptedEYE.ERG.NEITimePtRetina.left

Frequently asked questions

Code details

Code79778-7
SystemLOINC
Display namea-wave implicit time Left retina dark-adapted by ERG
Descriptiona-wave implicit time^dark-adapted
Short namea-wave impl time L ret dark-adapt ERG
Componenta-wave implicit time^dark-adapted
PropertyTime
TimingPt
System (specimen)Retina.left
ScaleQn
MethodElectroretinogram
ClassEYE.ERG.NEI
Example unitsms
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.54
Last changed2.68

Part names

a-wave implicit time^dark-adaptedTimePtRetina.leftQnElectroretinogramTime (e.g. seconds)Point in time (spot)Left retinaERG

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 79778-7 | HealthAssure