# K071078: .Decimal Range Compensator

- Pathway: 510(k) (Traditional)
- Applicant: .Decimal, Inc.
- Decided: May 22, 2007 after 35 days
- Product code: IXI (Block, Beam-Shaping, Radiation Therapy)
- Device class: 2
- Regulation: 21 CFR 892.5710
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 3 generations back to K000137 (2000). 7 ancestors in all.
9 later devices descend from it; 3 cite it directly.
0 of 17 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K040804: .Decimal Tissue Compensator/Intensity Modulator, Southeastern Radiation Products, Inc. (2004) Summary page 1.

## Most influential descendants
- K091911: Bolus Compensator (2009), 5 descendants of its own
- K214093: VSP Bolus (2022), 2 descendants of its own
- K121657: Proton Radiation Therapy Beam-Shaping Aperture Proton Radiaion Therapy Beam-Shping Range Compensator (2012), 2 descendants of its own
- K222639: VHA Radiotherapy Bolus (2022), 1 descendant of its own
- K211511: decimal Bolus (2021), 1 descendant of its own

## Indications for use
In proton therapy for cancer, a proton beam is aimed at the cancerous tissue using a large "snout". The "snout" is rotated around the patient using a large, three-story gantry. While the patient lies on a treatment table, the gantry rotates around and points the snout at pre-determined positions to maximize efficiency and dose delivery to the tumor volume. Each gantry angle, or "port", requires two custom-made, beam modifying, patient specific devices: a range compensator and an aperture. The range compensator is made out of acrylic or wax. The custom shape/design specifications for range compensators are generated out of the treatment planning system and are unique to each patient and each gantry angle (most patients will have 2-3 different gantry angles.) The outer dimensions/specifications are vendor specific, based upon the manufacturer of the proton delivery machines.

Source page: https://510kreport.com/device/K071078
Methodology: https://510kreport.com/methodology