use Data::Dumper;

my @test = ( 

        "1 This (is a test) with good parens", 
        "2 This is a (test with broken a paren", 
        "3 And this would be one) the other way",
        "4 Lastly, no parens"
);

print Dumper \@test;

foreach (@test) {

        my ($ip) = $_ =~ m#\((.*?)\)#;
        print " Match in parens: $ip\n" if $ip;

        my ($rp) = $_ =~ m#([^(]*?)\)# if $_ !~ /\(/;
        print " Match before right paren: $rp\n" if $rp;

        my ($lp) = $_ =~ m#\((.*)# if $_ !~ /\)/;
        print " Match after left paren: $lp\n" if $lp;
}

Output:
 Match in parens: is a test
 Match after left paren: test with broken a paren
 Match before right paren: 3 And this would be one