Puoi fare cosi ( esiste forse una funzione ma non la conosco )

codice:
<?php 
$variabile1 = 'pppppppppppppp';
$image =array(); 
$index=0; 
$image[]=array('idz'=>1,'idxtipo'=>$index++,'titleimg'=>$variabile1,'imgname'=>$variabile1); 
$image[]=array('idz'=>2,'idxtipo'=>$index++,'titleimg'=>$variabile1,'imgname'=>$variabile1); 
$image[]=array('idz'=>3,'idxtipo'=>$index++,'titleimg'=>$variabile1,'imgname'=>$variabile1) ;
$image[]=array('idz'=>4,'idxtipo'=>$index++,'titleimg'=>$variabile1,'imgname'=>$variabile1); 

function search($anArray,$aKey,$aValue) {
 foreach ($anArray as $key => $value) {
  //print_r($value);
  if ($value[$aKey]==$aValue) {
   return $value;	
	} //
 } // 
 return false;
} // 
$result = search($image,'idz',2);
if ($result == false) {
 print "not found";
} else {
 print_r($result);
} 
$result = search($image,'idz',20);
if ($result == false) {
 print "not found";
} else {
 print_r($result);
} 
 ?>