Source of Support: None, Conflict of Interest: None
Tissue compensating filters are used in radiotherapy to correct for the dose inhomogeneity produced in the irradiated volume due to irregular body contour. This paper describes the nonuniformity of the doses within the target volume without any tissue compensatior filter, manually designed compensating filter and the computer " designed compensating filter. The dose inhomogeneities produced without any Compensator, manually constructed aluminium compensator and computer designed compensating filter were compared and evaluated. The results show that dose variation can be as high as 30% without any compensating filter. This inhomageneity. Can be reduced to k 13% with the use of manually designed compensating filter constructed with aluminium blocks. The uniformity is further improved with the use of computer designed compensaing filter, where the dose ' variation inside the target volume would be within clinically desirable levels of * 3%. Such individually made
compensators have added advantages like less preparation time and enhanced accuracy.