Issue with Regular expression

[mac1sam]

I have the following string:

TechAccountDoc/canonical:Subaccount/canonical:ContractSection/canonical:TechnicalAccountMarkets/canonical:Subaccount[1]/canonical:TechnicalAccountMarket[canonical:MarketInfo/canonical:SourceKey = $MetaDataDoc/metadata:CustomHeaders/metadata:CustomHeader[metadata:Name="uidmarket"]/metadata:Value]/canonical:BalanceAmtItem[@type='692']

I am trying to write reg ex .... for ignoring whatever appears inside '[' and ']' . That means the output should be :

TechAccountDoc/canonical:Subaccount/canonical:ContractSection/canonical:TechnicalAccountMarkets/canonical:Subaccount/canonical:TechnicalAccountMarket/canonical:BalanceAmtItem

I have tried various combinations ... but i m unable to do so ...
can anyone help out with this issue??

Thanks in advance...
Megh