(170 days)
Leksell Gamma Knife® Perfexion™ is a teletherapy device intended for stereotactic irradiation of head structures ranging from very small target sizes of a few millimeters to several centimeters e.g. metastatic tumors, arteriovenous malformations, trigeminal neuralgia, medically refractory essential tremor, meningiomas, post-surgical pituitary adenomas and recurrent glioblastomas.
Leksell Gamma Knife Perfexion is a radiosurgery system for use in the stereotactic irradiation of intra-cranial structures. Surgery is achieved by delivering a prescribed dose as one or more shots of ionizing radiation to the exact site of the target.
Based on preoperative radiological examinations, the Leksell Gamma Knife Perfexion unit provides highly accurate external irradiation of intra-cranial structures using collimated beams of ionizing radiation.
Each unit contains 192 sealed sources of Cobalt 60.
Leksell Gamma Knife Perfexion systems consists of several units, physically separated in an Office side in the control room and a Medical side in the treatment room.
- The medical side consists basically of the radiation unit with a patient positioning . system. The system control and power units are placed inside the cover of the radiation unit.
- The office side consists of the operator console with control panel and office computer. .
This device, the Leksell Gamma Knife® Perfexion™, is a medical device for stereotactic radiosurgery. The provided documentation is a 510(k) summary, which focuses on demonstrating substantial equivalence to a legally marketed predicate device rather than presenting a de novo study with explicit acceptance criteria for a novel device.
Therefore, the typical acceptance criteria and study design for proving performance in the context of a new device are not directly applicable here. Instead, the "study" that proves the device meets the acceptance criteria is the demonstration of substantial equivalence to its predicate device (K120811). The acceptance criteria for this type of submission are implicitly that the new device is as safe and effective as the predicate and shares fundamental technical characteristics.
Here's an attempt to structure the information based on your request, highlighting where the traditional study components are not directly present or are addressed through literature review and comparison:
Acceptance Criteria and Device Performance
| Acceptance Criteria (Implicit for 510(k)) | Reported Device Performance |
|---|---|
| Safety: Device is as safe as the predicate device (K120811). | A risk analysis review was performed, confirming no changes to safety assessments. The device is concluded to be as safe as its predicate. |
| Effectiveness: Device is as effective as the predicate device (K120811) for its intended use. | A clinical literature review was conducted to support the safety and efficacy for new indications (essential tremor, pituitary adenomas, glioblastoma). Scientific advisors found extensive publications. The device is concluded to be as effective as its predicate. |
| Fundamental Technical Characteristics: Device shares fundamental technical characteristics with the predicate device (K120811). | The fundamental technical characteristics are stated to be the same as those of the predicate device. |
| New Indication Support: Safety and efficacy for added indications (essential tremor, pituitary adenomas, glioblastoma) are supported. | Clinical literature review and approval by physicians regarding clinical relevance based on previous models. Extensive scientific publications support expanded indications. |
Further Details on the "Study" and Ground Truth Establishment
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Sample size used for the test set and the data provenance:
- No explicit "test set" in the traditional sense of a new clinical trial was used.
- The "test set" information for demonstrating safety and effectiveness relied on a clinical literature review. The provenance of this data would be from various scientific publications, likely international, covering retrospective and prospective studies performed with Gamma Knife technology (including previous models and the predicate device).
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- The document mentions that "scientific advisors found extensive scientific publications" and "reports have been approved by physicians regarding clinical relevance, based on experience of previous models of the system."
- The number of experts is not specified.
- Their qualifications are generally described as "physicians" and "scientific advisors" with experience in the field of stereotactic radiosurgery and Gamma Knife systems. Specific years of experience (e.g., "radiologist with 10 years of experience") are not provided.
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Adjudication method for the test set:
- Not applicable in the context of a literature review. The "adjudication" was effectively through peer review of published scientific literature and the internal review and acceptance by the notifying company's scientific advisors and physicians.
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If a multi-reader multi-case (MRMC) comparative effectiveness study was done:
- No, a MRMC comparative effectiveness study was not explicitly done for this 510(k) submission. The submission relies on demonstrating equivalence to the predicate device and literature review for new indications, not a direct comparison of human readers with vs. without AI assistance (as this is a treatment device, not an diagnostic AI).
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not explicitly applicable. The Leksell Gamma Knife Perfexion is a complete radiosurgery system, not a standalone algorithm. Its performance is inherent to the system delivering radiation based on a treatment plan, which involves human input (e.g., physicians defining targets). The "performance" assessment focuses on the system's ability to safely and effectively deliver radiation as prescribed, consistent with its predicate.
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The type of ground truth used:
- For the demonstration of safety and effectiveness, the "ground truth" was derived from:
- Clinical outcomes data reported in the scientific literature for treatments performed with Leksell Gamma Knife systems (including previous models and the predicate).
- Expert consensus among physicians and scientific advisors regarding the clinical relevance and safety/efficacy based on existing knowledge and literature.
- Risk analysis review for safety, which serves as a form of internal validation against established safety standards.
- For the demonstration of safety and effectiveness, the "ground truth" was derived from:
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The sample size for the training set:
- Not applicable in the context of a 510(k) submission for a physical device, as there isn't a "training set" for an algorithm in the traditional sense here. Any "training" for the device's development would be part of engineering and design validation, not typically reported with a sample size like for an AI model.
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How the ground truth for the training set was established:
- Not applicable for the same reasons as above. The device's underlying physics and engineering principles are established, and its performance is validated against these principles and against the performance of the predicate device, not through an algorithm's training set as in AI.
§ 892.5750 Radionuclide radiation therapy system.
(a)
Identification. A radionuclide radiation therapy system is a device intended to permit an operator to administer gamma radiation therapy, with the radiation source located at a distance from the patient's body. This generic type of device may include signal analysis and display equipment, patient and equipment supports, treatment planning computer programs, component parts (including beam-limiting devices), and accessories.(b)
Classification. Class II.