We have had a query from a member who is translating content and has come across:

246883008 |Bulbar conjunctival drainage bleb | and subtypes:
•    246886000 |Drainage bleb, flat (disorder)|
•    246884002 |Drainage bleb, functional (disorder)|
•    246885001 |Drainage bleb, leaking (disorder)|

410724009 |Disorder of filtering bleb| and subtypes:
•    413665004 |Bleb associated endophthalmitis (disorder)|
•    13081000119109 |Complication of filtering bleb (disorder)|
•    410721001 |Failed filtering bleb (disorder)|
•    408765004 |Leaking filtering bleb (disorder)|
•    410722008 |Inadvertent filtering bleb (disorder)|
•    98851000119102 |Inflammation of filtering bleb (disorder)|
•    336691000119100 |Postprocedural blebitis (disorder)|
•    733310006 |Conjunctival blebitis following glaucoma surgery (disorder)|

246883008 |Bulbar conjunctival drainage bleb is defined in SNOMED as a blister of the conjunctiva; 410724009 |Disorder of filtering bleb| is defined with a separate morphology of filtering bleb but without a finding site. 

Their comment is - "We think these refer to the same condition. I could find only a handful articles that refer to drainage bleb, even fewer that were recent. Everything I found on drainage bleb or filtering bleb concerned the eye, usually in the context of a glaucoma. I think the entire branch of 246883008 |Bulbar conjunctival drainage bleb | should be retired as duplicate with 410724009 |Disorder of filtering bleb|; and I think the latter should be remodelled with finding site eye structure or even conjunctiva."

Are they correct or are these different?  I have also found it difficult to find recent references for drainage blebs.  With regards to the body structure involved for filtering blebs the procedure concepts such as 34854007 |Repair of filtering bleb (procedure)| use the body structure Anterior eyeball segment structure (body structure)

Appreciate your advice.

Thanks Elaine