LOB Size & actual size

Hi All,
I can get the actual size of the lob from the following command

select sum(dbms_lob.getlength (<lob column name>)) from <table_name>;

& the size of the lob segment from dba_segments

select bytes from dba_segments where segment_name ='<lob segment name>' and owner ='<table owner>';

How can I combine both in the same query? That s actual size of the lob & the segment_size for the lob. I have tried to capture both in single query but in vain.

can someone help?

thanks