operator's manual wireless dosimetry system - Best Medical Canada

OPERATOR'S MANUAL FOR THE SYSTEM
3. The detector is inserted into the central branch of an approved three way sterile
catheter via a ‘Y’ connector (see Figure 5-6: MOSFET Linear 5ive Array Before
Insertion in the 3-Way Catheter), which then is inserted in the urethra, rectum or
bladder. The radio-opaque marker, located on the tip of the array, helps visualize,
under fluoroscopy or CT, the 5 MOSFET positions relative to the internal bladder
wall (at the lower edge of the catheter balloon). The array size, its waterproof cable,
and the use of a Y type connector make body fluid evacuation clean and easy,
helping to make the patient more comfortable.
During the LDR Implant or HDR Procedure:
1. During the implant or HDR procedure, 5 dose points can be read directly from the
array, or remotely from a computer, displaying the real urethral dose profile
throughout the prostate location, compared to the planned profile.
2. From urethra dose readings, one can infer the maximum initial dose rate (IDRmax)
to the urethra and compare it to the recommended dose limit (1.5-2 mPD:
minimal Peripheral Dose). The measured dose versus distance curve along the
prostatic urethra contains the information about two factors related to the quality
of the implant: the dose rate at the base of the prostate and the length of urethra
that receives the mPD, compared to the length of the urethra measured with
ultrasound.
End of Implant Procedure:
1. After the implant, real time dosimetry using the Linear Array MOSFET Dosimeter
allows for correction of lack of the proper dose coverage at the prostate base.
However there is no practical way to reduce an excessive urethral dose, except
that a patient may be followed closely during post treatment phase and
considered to be at increased risk for urethral complications.
Figure 5-6: MOSFET Linear 5ive Array Before Insertion in the 3-Way Catheter
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