$dbconn = new PDO("odbc:MyDSNName", "бла", "бла");
$sqlimg = "select img	 
		   from dbo.Dok_img 
		   where kto=10001 and un_dok='104890'";
$stmt = $dbconn->prepare($sqlimg);
$result = $stmt->execute();
echo $result;

//Тут пытался в цикле показать данные поля img
while($row = $stmt->fetch())
	 {
         	echo'<tr><td>Картинка</td><td><input type="text" size="20" name="nom_k" value="'.$row['img'].'">';		 
	 }

$stmt->execute();

$stmt->execute();

$stmt = $dbconn->prepare("select img	 
		   from Dok_img 
		   where kto=10001 and un_dok='104890' and un='1'");
$stmt->execute();
echo "\nPDO::errorInfo():\n";
    print_r($stmt->errorInfo());
$stmt->bindColumn(1, $image, PDO::PARAM_LOB, 0, PDO::SQLSRV_ENCODING_BINARY);
$stmt->fetch(PDO::FETCH_BOUND);
echo $image;

$stmt = $dbconn->prepare("select img	 
		   from Dok_img 
		   where kto=10001 and un_dok='104890' and un='1'");
$stmt->execute();
echo "\nPDO::errorInfo():\n";
    print_r($stmt->errorInfo());
$stmt->bindColumn(1, $image, PDO::PARAM_LOB, 0, PDO::SQLSRV_ENCODING_BINARY);
$stmt->fetch(PDO::FETCH_BOUND);
echo $image;