send image in workflow mail body

Hi  All,

I have image problem in my workflow mail. Here is a situation

I am using visual studio sendmail activity in workflow. Body of mail is assigned from enhanced rich text field of sharepoint list. everything works well except if there is an image in sp list field. Images are saved in another sp picture library.   

here is my code

  SPList list = workflowProperties.Web.Lists[workflowProperties.Item.ParentList.Title];
                           SPListItem item = list.GetItemById(workflowProperties.Item.ID);
                          mailBody = item["Detail"].ToString();

could anyone help me with this problem. I need to send mail with  image inside.

Please help 

thanks