public function loadCollection(Mage_Catalog_Model_Resource_Category_Collection $collection, array $additionalFields = array())
 {
     $toLoad = array_unique(array_merge($this->_requiredCategoryFields, $this->_config()->megaMenuAttributeCodes(), $additionalFields));
     foreach ($toLoad as $field) {
         $collection->addAttributeToSelect($field);
     }
     $childreen = $collection->load($this->_debugDbLoads)->getItems();
     if ($this->_debugDbLoads) {
         foreach ($childreen as $child) {
             Mage::log('collection item loaded' . var_export($child->debug(), true));
         }
     }
     $this->_categoriesCache = $childreen + $this->_categoriesCache;
     return $childreen;
 }