Get Cell Value with column name in Php Excel

This is my excel sheet it has got lots of columns but i'm breaking down for ease in understanding the question

I'm reading Excel Sheet using PHP Excel and using rangeToArray() which give me all row from excel but i want the output as

Column as Key:Cell Value as Value

Currently I'm get output as

Col Index :Cell Value

So my Question is which is that function in Php Excel which return array with Column name and it Cell value?

try {
    $inputFileType = PHPExcel_IOFactory::identify($inputFileName);
    $objReader = PHPExcel_IOFactory::createReader($inputFileType);
    $objPHPExcel = $objReader->load($inputFileName);
} catch(Exception $e) {
    die('Error loading file"'.pathinfo($inputFileName,PATHINFO_BASENAME).'": '.$e->getMessage());
}
//  Get worksheet dimensions
$sheet = $objPHPExcel->getSheet(0); 
$highestRow = $sheet->getHighestRow(); 
$highestColumn = $sheet->getHighestColumn();
for ($row = 2; $row <= $highestRow; $row++){ 
    //  Read a row of data into an array
    $rowData = $sheet->rangeToArray('A' . $row . ':' . $highestColumn . $row,
                                            NULL,
                                            TRUE,
                                            FALSE);
    printArr($rowData);
    printArr("-------");

}

I get output as

Array
(
    [0] => Array
        (
            [0] => 27745186
            [1] => 42058
            [2] => DELL INTERNATIONAL SERVICES INDIA PVT LTD
            ...
            ...
         )
    [1] => Array
        (
            [0] => 27745186
            [1] => 42058
            [2] => DELL INTERNATIONAL SERVICES INDIA PVT LTD
            ...
            ...
         )
)

Desire Output

Array
(
    [0] => Array
        (
            [Invoice_no] => 27745186
            [Invoice Date] => 42058
            [Description] => DELL INTERNATIONAL SERVICES INDIA PVT LTD
            ...
            ...
         )
    [1] => Array
        (
            [Invoice_no] => 27745186
            [Invoice Date] => 42058
            [Description] => DELL INTERNATIONAL SERVICES INDIA PVT LTD
            ...
            ...
         )
)

via Chebli Mohamed