Bitrix menu ext. Get subdirectories from current directory

.bottom.menu_ext.php

<?
if(!defined("B_PROLOG_INCLUDED") || B_PROLOG_INCLUDED!==true)die();

if(CModule::IncludeModule("iblock")) {
	$IBLOCK_ID = 174;
	//пример выборки подразделов для раздела 
	$rsParentSection = CIBlockSection::GetList(array(), array('IBLOCK_TYPE' => '1c_catalog', 'IBLOCK_ID' => $IBLOCK_ID, 'CODE' => $_REQUEST["SECTION_CODE"]));
	if ($arParentSection = $rsParentSection->GetNext()) {
	   $arFilter = array('IBLOCK_ID' => $IBLOCK_ID,'>LEFT_MARGIN' => $arParentSection['LEFT_MARGIN'],'<RIGHT_MARGIN' => $arParentSection['RIGHT_MARGIN'],'DEPTH_LEVEL' => $arParentSection['DEPTH_LEVEL']+1); // выберет потомков без учета активности
	   $rsSect = CIBlockSection::GetList(array('left_margin' => 'asc'),$arFilter);
	   while ($arSect = $rsSect->GetNext()) {
	       $aMenuLinksExt[] = Array(
				$arSect['NAME'],
				"/catalog/".$arSect['CODE']."/",
				Array(),
				Array(),
				""
			);
	   }	
   }
}

$aMenuLinks = array_merge($aMenuLinksExt, $aMenuLinks);
?>