Software as a Medical Device, Real-World Evidence, Pediatric
Real-World Evidence
Submission
Device
Sponsor
RWD Sources
RWE Use Summary
Key Tags
K113725 · Sep 13, 2012
VIRTUOST
O.N. Diagnostics
Clinical fracture surveillance studies
The sponsor utilized results from clinical fracture surveillance studies to demonstrate that the device's estimates of whole-bone strength and load-to-strength ratio are at least as effective as existing DXA and QCT methods for fracture risk assessment.
Fracture risk assessment; Clinical surveillance; Observational study
VirtuOst uses data from computed tomography scans to estimate bone mineral density, bone strength, and a load-to-strength ratio. This information can be used by a physician to assess fracture risk, identify osteoporosis, and monitor therapy.
Device Story
VirtuOst is a standalone software package for analyzing computed tomography (CT) scans. It processes CT data to measure bone mineral density (BMD) (areal in g/cm2 and volumetric in mg/cm3), bone strength, and load-to-strength ratios at the proximal femur and vertebral body. Used by physicians in clinical settings to identify osteoporosis, assess fracture risk, and monitor therapy. The software provides quantitative outputs that assist clinicians in evaluating bone health and fracture probability. By estimating whole-bone strength and load-to-strength ratios, the device aids in clinical decision-making regarding patient management and therapeutic intervention.
Clinical Evidence
Clinical studies compared VirtuOst to DXA and CT-based predicate densitometers, demonstrating equivalent BMD measurements and precision via repositioning studies. Fracture surveillance studies showed VirtuOst's estimates of whole-bone strength and load-to-strength ratio are at least as effective as DXA and QCT BMD estimates for fracture risk assessment. Non-clinical cadaver experiments confirmed that VirtuOst's strength estimates for the proximal femur and vertebral body are statistically equivalent to direct mechanical testing results.
Technological Characteristics
Standalone software for CT image analysis. Measures BMD (areal and volumetric), bone strength, and load-to-strength ratios. Operates on CT scan input data. No specific hardware materials or energy sources; software-based analysis of existing radiological images.
Indications for Use
Indicated for physicians to assess fracture risk, identify osteoporosis, and monitor therapy in patients using CT scan data. For pediatric patients, provides estimates without classification; use only when benefit outweighs radiation risk.
Regulatory Classification
Identification
A bone densitometer is a device intended for medical purposes to measure bone density and mineral content by x-ray or gamma ray transmission measurements through the bone and adjacent tissues. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.
Image Analysis QCT Bone Mineral Analysis (BMA) Software (K992246)
Submission Summary (Full Text)
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May 11, 2023
Image /page/0/Picture/1 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of three parts: the Department of Health and Human Services seal, the FDA acronym in a blue square, and the words "U.S. Food & Drug Administration" in blue text. The Department of Health and Human Services seal is a stylized image of a caduceus, a symbol of medicine. The FDA acronym is in a bold, sans-serif font. The words "U.S. Food & Drug Administration" are in a smaller, sans-serif font.
% David Kopperdahl Director, Research and Development O.N. Diagnostics 2150 Shattuck Avenue, Suite 610 BERKELEY, CA 94704
Re: K113725
Trade/Device Name: VirtuOst Regulation Number: 21 CFR 892.1170 Regulation Name: Bone densitometer Regulatory Class: Class II Product Code: KGI
Dear David Kopperdahl:
The Food and Drug Administration (FDA) is sending this letter to notify you of an administrative change related to your previous substantial equivalence (SE) determination letter dated September 13, 2012. Specifically, FDA is updating this SE Letter to correct the regulation under which your device is classified.
Please note that the 510(k) submission was not re-reviewed. For questions regarding this letter please contact Dr. Lu Jiang at 240-402-5779 or lu.jiang@fda.hhs.gov.
Sincerely,
Lu Jiang
Lu Jiang, Ph.D. Assistant Director Diagnostic X-ray Systems Team DHT8B: Division of Radiological Imaging Devices and Electronic Products OHT8: Office of Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health
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Image /page/1/Picture/0 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo is a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" around the perimeter. Inside the circle is a stylized image of an eagle with its wings spread.
### DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health Service
Food and Drug Administration 10903 New Hampshire Avenue Document Control Room - WO66-G609 Silver Spring. MD 20993-0002
SEP 13 2012
Mr. David Kopperdahl Director, Research and Development O.N. Diagnostics, LLC 2150 Shattuck Avenue, Suite 610 BERKELEY CA 94704
Re: K113725
Trade/Device Name: VirtuOst Regulation Number: 21 CFR 892.1750 Regulation Name: Computed tomography x-ray system Regulatory Class: II Product Code: JAK, KGI Dated: August 3, 2012 Received: August 8, 2012
Dear Mr. Kopperdahl:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into class II (Special Controls), it may be subject to such additional controls. Existing major regulations affecting your device can be found in Title 21, Code of Federal Regulations (CFR), Parts 800 to 895. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Parts 801 and 809); medical device reporting (reporting of
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medical device-related adverse events) (21 CFR 803); and good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820). This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Parts 801 and 809), please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (301) 796-5450. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.
You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html.
Sincerely Yours,
Janine M. Morris
Director Bivision of Radiological Devices Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health
Enclosure
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# INDICATIONS FOR USE FORM
510(k) Number: K113725
Device Name: VirtuOst
Indications for Use:
VirtuOst uses data from computed tomography scans to estimate bone mineral density, bone strength, and a load-to-strength ratio. This information can be used by a physician to assess fracture risk, identify osteoporosis, and monitor therapy. For pediatric patients, VirtuOst provides these estimates without any classifications and should be used only when the benefit of obtaining these estimates outweighs the risk of radiation.
Prescription Use _________ (Part 21 CFR 801 Subpart D) . AND/OR
Over-The-Counter Use _________________________________________________________________________________________________________________________________________________________ (21 CFR Part 807 Subpart C)
(PLEASE DO NOT WRITE BELOW THIS LINE – CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
---
(Division Sign-Off)
Division of Radiological Devices Office of In Vitro Diagnostic Device Evaluation and Sat
510K K113725
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## 510(K) SUMMARY
| Date: | September 10, 2012 |
|--------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| | SEP 13 2012 |
| 1) Applicant Information | |
| 510(k) Owner: | O. N. Diagnostics, LLC<br>2150 Shattuck Ave. Suite 610<br>Berkeley, CA 94704 |
| Contact Person: | David Kopperdahl<br>Director, Research and Development<br>O. N. Diagnostics, LLC<br>2150 Shattuck Avenue, Suite 610<br>Berkeley, CA 94704<br>Phone 510-204-0688<br>Fax 510-356-4349 |
| Establishment Reg. No.: | Registration to occur following FDA clearance. |
#### 2) Device Identification
| Trade Name: | VirtuOst |
|------------------------|-----------------------|
| Common Name: | QCT Bone Densitometry |
| Classification Name: | Bone Densitometer |
| Regulation Number: | 21 CFR 892.1170 |
| Device Classification: | Class II |
# 3) Identification of Predicate Devices
K983028: Hologic QDR X-Ray Bone Densitometers with an added feature of Estimation of Fracture Risk from BMD
K894854: QCT Bone Mineral Density Analysis Software
K072664: GE Lunar Femur Strength Software Option
K992246: Image Analysis QCT Bone Mineral Analysis (BMA) Software
#### 4) Device Description
VirtuOst is a stand-alone software package that analyzes data in computed tomography (CT) scans to measure bone mineral density (BMD), bone strength, and a load-tostrength ratio at the proximal femur and vertebral body. BMD is measured from both a
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2D projection (in g/cm2) and a volumetric scan reconstruction (in mg/cm2) of the CT scan. VirtuOst measurements can be used by a physician to identify osteoporosis, assess fracture risk, and monitor therapy.
#### 5) Intended Use
VirtuOst uses data from computed tomography scans to estimate bone mineral density, bone strength, and a load-to-strength ratio. This information can be used by a physician to assess fracture risk, identify osteoporosis, and monitor therapy.
#### 6) Substantial Equivalence
# Summary of Technology Characteristics and Comparison with Predicate Devices
VirtuOst provides measurements of areal BMD, in g/cm2 and fracture risk classifications that are substantially equivalent to those obtained using predicate device K983028, and measurements of volumetric BMD, in mg/cm3, that are substantially equivalent to those obtained from predicate device K894854. VirtuOst also provides measurements of bone strength and a load-to-strength ratio, substantially equivalent to the structural properties of the whole bone that are provided by predicate device K072664. VirtuOst has the same technological characteristics as the predicate devices and is comparable in safety and effectiveness, and has the same intended uses.
## Summary of Performance Data
Clinical Performance Tests: Clinical studies demonstrated the substantial equivalence for measurements of bone mineral density between VirtuOst and predicate densitometers which used either DXA or computed tomography scans as input. Clinical repositioning studies demonstrated that the precision of outcomes from VirtuOst and predicate devices are equivalent. Results from a number of clinical fracture surveillance studies demonstrated that fracture risk assessment by VirtuOst estimates of whole-bone strength and the load-to-strength ratio, are at least as good as fracture risk assessment by DXA and QCT estimates of BMD.
Non-clinical Performance Tests: Strength of the proximal femur and vertebral body estimated using VirtuOst are statistically equivalent to strength as measured by direct mechanical testing in cadaver experiments.
#### 6) Conclusion
A comparison of fundamental technological characteristics as well as of data obtained from observational clinical studies demonstrates that the performance, safety and effectiveness of VirtuOst are substantially equivalent to those of the identified predicate devices.
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1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
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Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
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Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.