There are judgments about NO PAYMENT to runaway wives without valid reasons.
check http://mynation.net/docs/sitemap/ for all such judgments.
and if she desert you without valid reason you can go for Divorce after one year of seperation check that judgment too.
to counter 498a we should know some details of 498a, has she alleged that they gave dowry or you are harassing her for dowry etc etc. so we can advice or you can contact our local members for more details.