Справочник Пользователя для Sun Nuclear Corporation 1133
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1. Introduction
The Sun Nuclear model 1133 rf-IVD (or wireless IVD) is a system that measures the radiation output of a
radioactive substance such as a Co-60 source or a linear accelerator, during the treatment of a patient. The
system consists of 4 components: Display Module (user interface), Turtle (Communication Hub), Base Station (rf
transmitter and receiver), and Detector Pod (rf transmitter and receiver). The Base Station and Detector Pod are
identical and are interchangeable through system setup. The diode radiation detectors are connected to the
Detector Pod through coaxial BNC connectors.
radioactive substance such as a Co-60 source or a linear accelerator, during the treatment of a patient. The
system consists of 4 components: Display Module (user interface), Turtle (Communication Hub), Base Station (rf
transmitter and receiver), and Detector Pod (rf transmitter and receiver). The Base Station and Detector Pod are
identical and are interchangeable through system setup. The diode radiation detectors are connected to the
Detector Pod through coaxial BNC connectors.
The radiation therapist connects the radiation detectors (diodes) to the Detector Pod and then positions them on
the patient in order to measure the radiation from the accelerator. At this time, the patient is on the treatment
couch of the accelerator, already positioned for treatment. The detector pod is battery operated and is positioned
within 3 to 10 feet of the beam entrance to the patient. Also at this time, the beam is not on and the rf-IVD is not
making a dose measurement.
the patient in order to measure the radiation from the accelerator. At this time, the patient is on the treatment
couch of the accelerator, already positioned for treatment. The detector pod is battery operated and is positioned
within 3 to 10 feet of the beam entrance to the patient. Also at this time, the beam is not on and the rf-IVD is not
making a dose measurement.
The therapist then leaves the treatment room that is shielded with approximately 3 feet of concrete and a heavy
interlocked door. The patient is restrained on the couch because the treatment plan requires position accuracy to
within millimeters, therefore no movement is allowed. Dose measurement is then remotely started on the rf-IVD
from the Display Module in the control room and the accelerator beam turned on. A treatment fraction generally
lasts for ½ minute or so. When the beam turns off, the rf-IVD is stopped and the dose value is displayed. The rf-
IVD display value is recorded or printed on an accessory printer. The therapist then enters the room and removes
the detector from the patient.
interlocked door. The patient is restrained on the couch because the treatment plan requires position accuracy to
within millimeters, therefore no movement is allowed. Dose measurement is then remotely started on the rf-IVD
from the Display Module in the control room and the accelerator beam turned on. A treatment fraction generally
lasts for ½ minute or so. When the beam turns off, the rf-IVD is stopped and the dose value is displayed. The rf-
IVD display value is recorded or printed on an accessory printer. The therapist then enters the room and removes
the detector from the patient.
The recorded rf-IVD measurement is a QA test that verifies the dose output during treatment from the radiation
machine. The actual treatment plan is calculated in the Treatment Planning Computer (TPC – not part of the rf-
IVD) which uses dosimetry data acquired from a NIST traceable calibrated ion chamber and 3D water phantom.
The plan output should also include the "expected" dose at the point of the IVD detector placement. Then the
measured IVD dose and the expected TPC dose can be compared for verification. If the expected dose is not
verified, the measured dose should not be used to adjust future treatments. Instead, an investigation should be
conducted as to why the error occurred. The IVD is calibrated at the institution using the NIST traceable calibrated
ion chamber as a standard, the same standard that is used to calibrate the accelerator and the TPC. Therefore,
the IVD offers a closed loop QA test of the implementation of the plan.
machine. The actual treatment plan is calculated in the Treatment Planning Computer (TPC – not part of the rf-
IVD) which uses dosimetry data acquired from a NIST traceable calibrated ion chamber and 3D water phantom.
The plan output should also include the "expected" dose at the point of the IVD detector placement. Then the
measured IVD dose and the expected TPC dose can be compared for verification. If the expected dose is not
verified, the measured dose should not be used to adjust future treatments. Instead, an investigation should be
conducted as to why the error occurred. The IVD is calibrated at the institution using the NIST traceable calibrated
ion chamber as a standard, the same standard that is used to calibrate the accelerator and the TPC. Therefore,
the IVD offers a closed loop QA test of the implementation of the plan.
SPECIFICATIONS
Diode Detector Inputs
Quantity: 3
Connector Type: BNC coax, 2 lug
Detector Temperature Compensation: Auto, within 0.1
Connector Type: BNC coax, 2 lug
Detector Temperature Compensation: Auto, within 0.1
°
C (negative detector current only)
Calibration: User calibrated against ion chamber standard
Repeatability:
Repeatability:
±
0.2% or
±
0.1 cGy
Detector Requirements: n or p type diodes responding between 5 to 100 nC/Gy
Polarity: Bipolar, i.e., measures positive or negative detector current
Current Limit:
Polarity: Bipolar, i.e., measures positive or negative detector current
Current Limit:
±
40 nA average radiation current or 1.0 nC per radiation pulse
Leakage: Auto compensation
Warm-up Time: < 30 seconds
Environmental Temperature: 15
Warm-up Time: < 30 seconds
Environmental Temperature: 15
°
C to 32
°
C
Relative Humidity: 10% to 90% rh, non condensing
Component Definitions, size and weight
Detector Pod: Measure dose received by diode detectors, 3 diodes per pod; 7x12x3 cm, 340 gm
Base Station: Data relay between wireless Detector Pod and Turtle; 7x12x3 cm, 340 gm
Turtle: Hardwired communication hub (RS-232 or USB) between PC, Display, and Pod or Base Station;
Base Station: Data relay between wireless Detector Pod and Turtle; 7x12x3 cm, 340 gm
Turtle: Hardwired communication hub (RS-232 or USB) between PC, Display, and Pod or Base Station;
7x12x3 cm, 340 gm
Display: User keypad and display module for start and display of dosimetry measurements; 14x16x3.5 cm, 780 gm
Printer: Seiko Thermal DPU-414, serial port to Display, 9x320 dots/line, 40 column=9 cm; 16x17x6.6 cm, 580 gm
Cable: Display unit to Turtle (communicator) via 8 pin modular connector/cable, 2.4 m.
Cable: Turtle to Base Station (located in treatment room) via 6 pin modular connector/cable, 25 m.
Printer: Seiko Thermal DPU-414, serial port to Display, 9x320 dots/line, 40 column=9 cm; 16x17x6.6 cm, 580 gm
Cable: Display unit to Turtle (communicator) via 8 pin modular connector/cable, 2.4 m.
Cable: Turtle to Base Station (located in treatment room) via 6 pin modular connector/cable, 25 m.