{{tag>ddx ERG}} 
====== Electronegative ERG ======
  * Loss of "b" wave in a dark adapted mixed rod-cone response
<WRAP round box 60%>
{{::erg.jpeg|}} \\
[[https://eyewiki.org/Electroretinogram|from AAO EyeWiki ERG]]
</WRAP>

==== Possible Causes ====

  * CSNB (Oguchi’s)
  * CRVO / acute CRAO
  * [[linked_retinoschisis|X-linked retinoschisis]]
  * Siderosis
  * Myotonic dystrophy
  * Duschenne muscular dystrophy
  * [[batten_disease|Batten disease]]
  * Quinine toxicity / methanol toxicity
  * MAR (melanoma-associated retinopathy / CAR (cancer-associated retinopathy)
  * Retinoschisis