(42 days)
The Standard Imaging HDR 1000 Plus Well Chamber is a well-type chamber. It is specifically designed to measure the amount of radiation of brachytherapy sources, including high-dose-rate (HDR), low-dose-rate (LDR), intravascular (IVB) and electronic (x-ray) sources, with the appropriate calibration from an accredited dosimetry calibration laboratory. Sources must be measured using the appropriate and specific source holder as described in the labeling.
The Standard Imaging HDR 1000 Plus Well Chamber is a well-type chamber. It is specifically designed to measure the amount of radiation of brachytherapy sources, including high-dose-rate (HDR), low-dose-rate (LDR), intravascular (IVB) and electronic (x-ray) sources, with the appropriate calibration from an accredited dosimetry calibration laboratory. Sources must be measured using the appropriate and specific source holder as described in the labeling.
It is recommended that the chamber be calibrated every two years, as is standard practice for other ionization chambers. Initially, the calibration factor is given in the calibration report from an Accredited Dosimetry Calibration Laboratory (ADCL).
The measurement of brachytherapy sources requires an electrometer with a calibrated scale for measuring currents in the range from 10-12 A to 10-7A. Alternatively, a calibrated charge scale may be used with timed runs. If integral charge techniques are used with the time determined by the HDR irradiator timer, the contribution from the source transit-time should be taken into account.
The HDR 1000 Plus Well Chamber has a vent hole to maintain the internal air at ambient atmospheric pressure. Thus, the readings obtained must be corrected for ambient temperature and pressure to the temperature and pressure of calibration (22º C and 760 mm Hg) at "normal" relative humidity (50% ± 25%non-condensing) in the usual accepted manner. The HDR 1000 Plus Well Chamber has available different inserts for IVB, HDR, LDR and x-ray measurements.
The HDR 1000 Plus Well Chamber has a conventional triax connector and cable to be connected to a suitable electrometer. A bias of 300 volts must be applied to the electrometer lowimpedance connection relative to chassis ground. The voltage polarity effect is less than 0.1%. If desired, a second bias level of 150 volts can also be used to determine the ionic recombination loss at 300 V.
Here's an analysis of the provided text regarding the acceptance criteria and study for the Standard Imaging HDR 1000 Plus Well Chamber (modifications to):
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Compliance with IEC 60601-1 (Medical Electrical Equipment for general requirements) | The device was designed to comply with the limited applicable portions of IEC 60601-1. |
| Compliance with IEC 60601-1-2 (EMC/EMI) | The device was designed to comply with the limited applicable portions of IEC 60601-1-2. |
| Compliance with EN 980 (Symbols) | The device was designed to comply with the limited applicable portions of EN 980. |
| Compliance with EN 1041 (Manuals) | The device was designed to comply with the limited applicable portions of EN 1041. |
| Voltage polarity effect less than 0.1% | The device reports a voltage polarity effect of less than 0.1%. |
| Ability to maintain internal air at ambient atmospheric pressure (vent hole) | The device has a vent hole to maintain internal air at ambient atmospheric pressure, requiring correction for temperature and pressure. |
| Substantial equivalence in design concepts, technologies, materials, and intended uses to predicate devices. | Stated that the device and predicate devices are substantially equivalent in design concepts, technologies, materials and intended uses. |
| Validation through calibration testing | The device has been validated through calibration testing by the University of Wisconsin - Madison, Department of Medical Physics Accredited Dosimetry Calibration Laboratory. |
Important Note: The document doesn't explicitly state quantitative acceptance criteria in terms of specific performance thresholds (e.g., "accuracy ±X%", "precision ≤Y%"). Instead, it focuses on compliance with standards and substantial equivalence. The "reported device performance" is primarily descriptive of design features and a general statement of validation.
2. Sample Size Used for the Test Set and Data Provenance
The provided text does not specify a sample size for a test set. There isn't a "test set" in the traditional sense of a dataset used to evaluate an AI model or a new medical device against a known ground truth.
The data provenance is related to calibration testing performed by the University of Wisconsin - Madison, Department of Medical Physics Accredited Dosimetry Calibration Laboratory. This implies a controlled, prospective experiment or series of measurements under specific laboratory conditions. The country of origin is the USA.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not applicable as the document describes a physical medical device (a well chamber) and its validation through calibration, not an AI or diagnostic system requiring expert interpretation of data for ground truth. The "ground truth" for this device would be established by the highly precise and traceable reference standards used by the Accredited Dosimetry Calibration Laboratory (ADCL), which are maintained by experts in dosimetry and metrology. While not explicitly numbered, the personnel at an ADCL are by definition highly qualified in radiation dosimetry.
4. Adjudication Method for the Test Set
This information is not applicable for the same reasons as point 3. Adjudication methods are typically used when subjective expert interpretation is involved in establishing ground truth for a diagnostic or AI system.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study Was Done, If So, What Was the Effect Size of How Much Human Readers Improve with AI vs Without AI Assistance
This information is not applicable. The device is a measurement instrument for radiation, not an AI or diagnostic tool where human readers assess cases.
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) Was Done
This information is not applicable. The device is a physical instrument, not an algorithm. Its operation involves a human user (a dosimetry professional) who connects it to an electrometer and performs measurements, then applies corrections.
7. The Type of Ground Truth Used
The ground truth used for the validation of the HDR 1000 Plus Well Chamber is based on traceable dosimetry standards and calibration processes maintained by an Accredited Dosimetry Calibration Laboratory (ADCL). This involves highly accurate reference sources and measurement techniques, ensuring the device's readings are accurate relative to established physical units of radiation. It's essentially a type of "metrological ground truth" rather than expert consensus, pathology, or outcomes data.
8. The Sample Size for the Training Set
This information is not applicable. The device is a physical instrument, not a machine learning model, so there is no "training set."
9. How the Ground Truth for the Training Set Was Established
This information is not applicable for the same reasons as point 8.
§ 892.5700 Remote controlled radionuclide applicator system.
(a)
Identification. A remote controlled radionuclide applicator system is an electromechanical or pneumatic device intended to enable an operator to apply, by remote control, a radionuclide source into the body or to the surface of the body for radiation therapy. This generic type of device may include patient and equipment supports, component parts, treatment planning computer programs, and accessories.(b)
Classification. Class II.