private function getItems($itemValues, string $itemType): array
    {
        $items = [];

        foreach ((array) $itemValues as $itemValue) {
            try {
                $backend = $this->backendRegistry->getBackend($itemType);
                $item = $backend->loadItem($itemValue);
                $items[$item->getValue()] = $item;
            } catch (NotFoundException $e) {
                // Do nothing
            }
        }

        return $items;
    }