sql server - Rewrite SQL Query- I need to replace NOT IN with Join -

I have a query in my production environment that is taking a long time to execute. I did not write this question, but I should get a way to hurry it because it is causing big performance problems at this time. I do not need to change with joining the left but to make sure that how to write it again it looks like this in the moment

  select Top 1 from IT.ITEMID ( Select Cast (Itemid in numeric form) + 1 Itemid items from ISNUMERIC (Itemid) = 1 and Artists (Itemid Numerical)> = 50000) Where it is not IT.ITEMID (Cast Itemid Item Item in numeric form) Where ISNUMERIC (Itemid) = 1. Order by IT.ITEMID ORDER   
 Please suggest bay from With the joining Left level performance I wanted it to rewrite have any help / guidance is greatly appreciated.   
  "itemprop =" text "> 
 after this one -  
 ; With CTE (Separate Selection Itemid = Case when ISLDERIC (Itemid) = 1 itemid End Items) Select Top 1 Itemid = Itemid + 1 CTE T Where Itemid & gt; = 50000 and does not exist (Select from CTE T2 1 ou t.ITEMID + 1 = t2 .ITEMID) by ORDER IIDID