Use the same dbcontext in multiple methods

i have a problem, i would use same dbContext in multiple methods, example:

public class Communication
{
   public Response AddCommunication(Commnucation myComm)
   {
      using(MYDB dbContenxt = new MYDB())
       {
           DBCOMMUNICATION dbComm = new DBCOMMUNICATION
           {
               ID = myComm.Id,
               NAME = myComm.Name,
               SUBJECT = myComm.Subject,
               MESSAGE = myComm.Message
           };

           if(myComm.Images != null && myComm.Images.Count > 0)
           {
               foreach(var image in Images)
               {
                   IMAGES dbImages = new IMAGES
                   {
                       ID_COMMUNICATION = myComm.Id,
                       NAME = image.Name,
                       VALUE = image.Value
                   };
                   dbContext.IMAGES.add(dbImages);
               }
           }

           if(myComm.Attachments != null && myComm.Attachments.Count > 0)
           {
               foreach(var image in Images)
               {
                   same work .......
                }
           }
        dbContext.SaveChanges();    
       }
      .......
      .......
    }
}

i would extract methods that use foreach loop, example:

 if(myComm.Images != null && myComm.Images.Count > 0)
       {
            AddImages(myComm);
       }

and in the method AddImages i would use the same dbContext for add but use SaveChanges only in AddCommunication. Which is the best practice to do this?? Use a Singleton Pattern for dbContext? Please help me. Thanks and sorry for my bad english.