diff --git a/Routing/ImagineLoader.php b/Routing/ImagineLoader.php
index <HASH>..<HASH> 100644
--- a/Routing/ImagineLoader.php
+++ b/Routing/ImagineLoader.php
@@ -25,7 +25,7 @@ class ImagineLoader extends Loader
 
     public function load($resource, $type = null)
     {
-        $requirements = array('_method' => 'GET', 'filter'  => '[A-z0-9_\-]*', 'path'    => '.+');
+        $requirements = array('_method' => 'GET', 'filter' => '[A-z0-9_\-]*', 'path' => '.+');
         $defaults     = array('_controller' => 'imagine.controller:filterAction');
         $routes       = new RouteCollection();
 
@@ -33,8 +33,10 @@ class ImagineLoader extends Loader
             foreach ($this->filters as $filter => $options) {
                 if (isset($options['path'])) {
                     $pattern = '/'.trim($options['path'], '/').'/{path}';
-                } else {
+                } elseif ('' !== $filter) {
                     $pattern = '/'.trim($this->cachePrefix, '/').$filter.'/{path}';
+                } else {
+                    $pattern = '/'.trim($this->cachePrefix, '/').'{path}';
                 }
 
                 $routes->add('_imagine_'.$filter, new Route(
allow a filter to be an empty string