Hi,
You can use SqlTransaction to delete the image from database under this transaction. Then delete the image from the folder.
I think you can use this code to delete image :
string filePath = Server.MapPath("~/" + PathDB);
if (System.IO.File.Exists(filePath))
{
System.IO.File.Delete(filePath);
}
Where PathDB contains the path from database.
I hope it will be helpful for you.
good luck