Also, if some articles have images and others don't, you could hide the placeholder or red-X.
In the insert and update forms for the images and content records, you could add a checkbox for 'image_exists' with a binary value (value if checked = 1) with an equivalent field in your database table.
Then you could add a 'Show Region' server behaviour ( i.e. WebAssist's Show Region Utility) based on the value you have assigned in the database via the checkbox.
Select the image or image container and from the recordset with the 'image_exists' data, you could make the show region as:
<?php
if ("".$row_theRecordset['image_exists'] ."" == "1") {
?>
[Your image or image-container code here]
<?php
}
?>
Images or image containers without a ticked 'image_exists' checkbox would be hidden.