A conversion table for use with varying S.S.D. and depth in treatment planning.

In the clinical treatment of patients the physician often changes from treating S.S.D. to treating S.A.D. or another S.S.D. This alteration in treatment geometry can occur because of easier treatment set-up due to changes in the port size, the depth or other physical parameters. A group of tables has been developed and used for several years to present a single parameter from the multiple factors involved that will allow more simple conversion for the physician, physicist or technician performing the calculations without immediate access to a programmable computer or calculator. The tables are presented and examples of their use given for typical situations.