displaying an image stored in a mysql blob

Question

when i run the code below it displays an image that is stored in a mysql Db as a blob variable. The problem is if I echo out anything else, even something as simple as echo '--------'; before I call the image, the image will not display. only random characters display. if i echo out anything after the image the image displays but nothing does after it. Can someone tell me why this is and how i can go about displaying other items and the image together, thanks

<?php

include("inc/library.php");

connectToDatabase();

$sql = "SELECT * FROM theBlogs WHERE ID = 1;";

$result = mysql_query($sql) or die(mysql_error());  
$row = mysql_fetch_array($result);

header("Content-type: image/jpeg");
echo $row['imageContent'];
$db->close();

?>