# K992689: MU Plus

- Pathway: 510(k) (Traditional)
- Applicant: Rad Therapy Solutions, Inc.
- Decided: Feb 10, 2000 after 184 days
- Product code: IYE (Accelerator, Linear, Medical)
- Device class: 2
- Regulation: 21 CFR 892.5050
- 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 K862643 (1987). 10 ancestors in all.
No later device cites it as a predicate yet.
0 of 11 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K914698: Setup Computer with Software V-1261,62 and 63, K.S., Inc. (1992) Summary page 1.
- K980379: Prowess Pro-Sim, Ssgi Prowess Systems (1998) Summary page 1.

## Indications for use
MU Plus! is a quality assurance tool for monitor unit calculations performed in radiation oncology clinics. MU Plus! is designed to be used as a verification of treatment planning derived monitor unit settings or hand generated monitor unit settings. Monitor unit calculations for linear accelerators are performed by various staff of radiation oncology clinics, including medical physicists, dosimetrists, and radiation therapists. MU Plus! also contains a diode measurement verification program which predicts an expected diode reading based on a formalism similar to the monitor unit calculations.

Source page: https://510kreport.com/device/K992689
Methodology: https://510kreport.com/methodology