The ACUSON Redwood ultrasound imaging system is intended to provide images of, or signals from, inside the body by an appropriately trained healthcare professional in a clinical setting for the following applications: Fetal, Abdominal, Pediatric, Small Parts, OB/GYN (useful for visualization of the ovaries, follicles, uterus, and other pelvic structures), Adult, Pediatric and Neonatal Cardiac, Pelvic, Neonatal Cephalic, Adult Cephalic, Vascular, Musculoskeletal, Superficial Musculoskeletal, Transcranial, and Peripheral Vascular.

The system supports the Ultrasound-Derived Fat Fraction (UDFF) measurement tool to report an index that can be useful as an aid to a physician managing adult patients with hepatic steatosis.

The system also provides the ability to measure anatomical structures: fetal, abdominal, pediatric, small organ, neonatal cephalic, adult cephalic, cardiac (adult, pediatric and neonatal), transesophageal, transrectal, transvaginal, peripheral vessel, musculoskeletal (conventional), musculoskeletal (superficial), and calculation packages that provide information to the clinician that may be used adjunctively with other medical data obtained by a physician for clinical diagnosis purposes.

Device Description

The ACUSON Redwood Diagnostic Ultrasound System is multi-purpose, mobile, softwarecontrolled, diagnostic ultrasound system with an on-screen display for thermal and mechanical indices related to potential bio-effect mechanisms. Its function is to acquire harmonic ultrasound echo data and display it in B-Mode, M-Mode, Pulsed (PW) Doppler Mode, Continuous (CW) Doppler Mode, Color Doppler Mode, Color M mode, Doppler Tissue Image mode, Amplitude Doppler Mode, Combination modes, Harmonic Imaging and 3D Imaging modes, and 4D imaging modes on a flat panel display for diagnostic ultrasound imaging.

AI/ML Overview

Here's an analysis of the acceptance criteria and the study proving the device meets them, based on the provided text:

Preamble: The provided document is a 510(k) summary for the ACUSON Redwood Diagnostic Ultrasound System. The core of the study described focuses on the new "Ultrasound-Derived Fat Fraction (UDFF)" feature. The general diagnostic ultrasound system itself is noted to use "the same technology and principles as existing predicate devices" and therefore "clinical studies were not required to support substantial equivalence" for its broader functionality. The following information pertains specifically to the UDFF feature.

Acceptance Criteria and Device Performance (UDFF Feature)

Acceptance Criteria	Reported Device Performance
Study 1: Correlation with Predicate Device (ACUSON Sequoia UDFF)
Significance level p-Value < 0.05 in a two-tailed test for difference	Pearson Correlation coefficient between UDFF on ACUSON Redwood and ACUSON Sequoia was 0.98, and the difference is not statistically significant (p=0.792 and t-statistic = -0.263). (This indicates a strong correlation and no statistically significant difference, meeting the criterion for equivalence.)
Study 1: Clinical Reliability (Test-retest ICC)
Test-retest ICC greater than 0.75	ICC = 0.98. (This indicates excellent reliability, meeting the criterion.)
Study 1: Measurement Acquisition Time
Exam time less than 60 seconds	All subjects acquisition time was within 22 seconds. (This meets the criterion with a significant buffer.)
Study 2: Agreement with MRI-PDFF (Bland-Altman analysis)
Absolute mean difference less than 5 percentage points AND Bland-Altman limits of agreement within ±15 percentage points	Redwood UDFF and MRI's PDFF had Bland-Altman limits of agreement between -3.1 to 6.3 percentage points with a mean absolute difference of 1.59 percentage points. (Both parts of the criterion are met: 1.59% is < 5%, and -3.1 to 6.3 is well within the ±15% range, indicating good agreement.)
Study 2: Clinical Accuracy compared to MRI-PDFF (AUROC)
AUROC greater than 0.80	Performance of UDFF on ACUSON Redwood showed strong performance as compared to MRI-PDFF with AUROC > 0.85. (This meets the criterion for strong diagnostic accuracy.)

Further Study Details for UDFF Feature:

Sample Sizes Used for the Test Set and Data Provenance:
- Study 1: N = 30 subjects
  - Ethnicity/Country: 15 from USA, 15 from Korea
  - Sex: 15 Male, 15 Female
  - Retrospective or Prospective: Not explicitly stated, but the description of "To verify the clinical reliability...To record the UDFF measurement acquisition time" suggests it was a prospective data collection for this study.
- Study 2: N = 28 subjects
  - Ethnicity/Country: 28 from Korea
  - Sex: 20 Male, 8 Female
  - Retrospective or Prospective: Not explicitly stated, but given the objective "To verify that UDFF of ACUSON Redwood shows good agreement with MRI-PDFF" and "To verify the clinical accuracy...", it implies prospective data collection where both UDFF and MRI-PDFF were acquired for correlation.
Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:
- Study 1: This study primarily focused on comparing the ACUSON Redwood UDFF to the ACUSON Sequoia UDFF and internal consistency (test-retest reliability). Ground truth, in the sense of a definitive diagnostic outcome, was not the primary endpoint that would require expert adjudication. The "ground truth" here is the measurement from the established predicate device (ACUSON Sequoia UDFF) and the consistency of the Redwood's own measurements.
- Study 2: The ground truth for this study was MRI-PDFF (Magnetic Resonance Imaging Proton Density Fat Fraction). This MRI-PDFF is considered a quantitative reference standard for liver fat quantification. The document does not specify the number of human readers/experts directly involved in establishing the MRI-PDFF values for the study, as MRI-PDFF is typically an objective, quantitative measurement derived from MRI sequences and software, rather than a subjective expert read needing adjudication.
Adjudication Method for the Test Set:
- Not applicable as the ground truths (predicate device measurements and MRI-PDFF) are presented as objective measurements and not subjective expert interpretations requiring adjudication.
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:
- No, an MRMC comparative effectiveness study involving human readers and AI assistance was not mentioned or performed for the UDFF feature as described. The UDFF is a standalone software tool for measurement.
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Yes, the studies evaluate the performance of the UDFF software tool itself in its ability to quantify fat fraction, either compared to a predicate device's software tool (Study 1) or to MRI-PDFF as a reference standard (Study 2). The results (Pearson Correlation, ICC, bland-Altman, AUROC) are metrics of the algorithm's performance.
The type of ground truth used:
- Study 1: The ground truth was the Ultrasound-Derived Fat Fraction (UDFF) measurement obtained from the predicate device (ACUSON Sequoia), and the internal consistency of the ACUSON Redwood UDFF measurements (test-retest).
- Study 2: The ground truth was MRI-PDFF (Magnetic Resonance Imaging Proton Density Fat Fraction), which is a quantitative imaging biomarker considered a non-invasive gold standard for liver fat content.
The sample size for the training set:
- The document does not provide information regarding the sample size of any training set used for the UDFF algorithm. This section focuses on validation studies.
How the ground truth for the training set was established:
- The document does not provide information regarding how the ground truth for any potential training set was established.

Summary

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November 15, 2024

Image /page/0/Picture/1 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: the Department of Health & Human Services logo on the left and the FDA logo on the right. The FDA logo is in blue and includes the letters "FDA" in a square and the words "U.S. Food & Drug Administration".

Siemens Medical Solutions USA, Inc. % Prithul Bom Most Responsible Person Regulatory Technology Services, LLC 1000 Westgate Drive, Suite 510k Saint Paul, Minnesota 55114

Re: K243299

Trade/Device Name: ACUSON Redwood Diagnostic Ultrasound System Regulation Number: 21 CFR 892.1550 Regulation Name: Ultrasonic pulsed doppler imaging system Regulatory Class: Class II Product Code: IYN, IYO, ITX, OIJ Dated: October 18, 2024 Received: October 18, 2024

Dear Prithul Bom:

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 (the 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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

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Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).

Your device is also subject to, among other requirements, the Quality System (OS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).

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 Part 801); medical device reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.

All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-device-advicecomprehensive-regulatory-assistance/unique-device-identification-system-udi-system.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatory

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assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

YANNA S. KANG -S

Yanna Kang, Ph.D. Assistant Director Mammography and Ultrasound Team DHT8C: Division of Radiological Imaging and Radiation Therapy Devices OHT8: Office of Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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Indications for Use

Submission Number (if known)

K243299

Device Name

ACUSON Redwood Diagnostic Ultrasound System

ndications for Use (Describe)

The system supports the Ultrasound-Derived Fat Fraction (UDFF) measurement tool to report an index that can be useful as an aid to a physician managing adult patients with hepatic steatosis.

The system also provides the ability to measure anatomical structures: fetal, abdominal, pediatric, small organ, neonatal cephalic, adult cephalic, cardiac (adult, pediatric and neonatal), transesophageal, transvaginal, peripheral vessel, musculoskeletal (conventional), musculoskeletal (superficial), and calculation packages that provide information to the clinician that may be used adjunctively with other medical data obtained by a physician for clinical diagnosis purposes.

Operating Modes

· 2D-mode
2D-mode with Harmonic imaging
· Color flow Doppler
Color (velocity)
Power (energy)
Doppler Tissue Imaging
· Pulsed Wave Doppler
Pulsed Wave Doppler Tissue Imaging
High Pulsed Repetition Frequency Pulsed Wave Doppler
· Continuous Wave Doppler
Steerable Continuous Wave Doppler for phased array transducers
Auxiliary Continuous Wave Doppler for pencil transducers
· M-mode
M-mode with Harmonic imaging
Anatomical M-mode
· Volume Imaging

Combined Modes

· 2D-mode with Color
· 2D-mode with power
· 2D/Doppler
· 2D/Doppler with Color
· 2D/Doppler with power
· 2D/M-mode

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· 2D/M-mode with color

· 2D/Anatomical M-mode

Type of Use (Select one or both, as applicable)

Prescription Use (Part 21 CFR 801 Subpart D)

Over-The-Counter Use (21 CFR 801 Subpart C)

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510(k) Summary

K243299

Date:	November 15, 2024
1. Sponsor:	Siemens Medical Solutions USA, Inc.Ultrasound Division22010 South East 51st StreetIssaquah, Washington 98029
Contact Person:	Shilpa RapakaPhone: 512-913-1053
Secondary Contact:	Emily WooPhone: 82-10-4697-2683
2. Device Name:	ACUSON Redwood Diagnostic Ultrasound System
Common Name:Classification:	Diagnostic Ultrasound System with AccessoriesRegulatory Class: IIClassification Panel: Radiology
	Classification Name	21 CFR Section	Product Code
	Ultrasonic Pulsed Doppler Imaging System	892.1550	IYN
	Ultrasonic Pulsed Echo Imaging System	892.1560	IYO
	Diagnostic Ultrasound Transducer	892.1570	ITX
	Biopsy Needle Guide Kit	892.1560	OIJ
Manufacturing Site:	Siemens Healthcare s.r.oPanattoni Park Kosice Airport ul.Andreja Kvasa 5040 17, Kosice-Barca, Slovakia

3. Legally Marketed Predicate Device and Reference Device

The ACUSON Redwood Diagnostic Ultrasound System is multi-purpose diagnostic ultrasound system with proprietary software and optional accessories and is substantially equivalent to the company's own Ultrasound devices, the ACUSON Redwood (K210743) which is the primary predicate device and the ACUSON Sequoia (K232145) as the reference device.

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4. Device Description

5. Intended Use/Indications for Use

The system supports the Ultrasound-Derived Fat Fraction (UDFF) measurement tool to report an index that can be useful as an aid to a physician managing adult patients with hepatic steatosis.

Operating Modes

2D-mode .
- । 2D-mode with Harmonic imaging
Color flow Doppler .
- Color (velocity) ー
- Power (energy) -
- Doppler Tissue Imaging
Pulsed Wave Doppler .
- Pulsed Wave Doppler Tissue Imaging —
- High Pulsed Repetition Frequency Pulsed Wave Doppler -
. Continuous Wave Doppler
- Steerable Continuous Wave Doppler for phased array transducers -
- Auxiliary Continuous Wave Doppler for pencil transducers ー
M-mode
- M-mode with Harmonic imaging l
- l Anatomical M-mode
Volume Imaqinq

Combined Modes

2D-mode with Color .

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2D-mode with power
. 2D/Doppler
. 2D/Doppler with Color
2D/Doppler with power
2D/M-mode ●
2D/M-mode with color .
2D/Anatomical M-mode

6. Substantially Equivalent Devices and Summary of Technological Characteristics

The ACUSON Redwood Diagnostic Ultrasound System is substantially equivalent to the company's own Ultrasound devices that are already cleared for distribution in the United States. The predicate and reference devices of ACUSON Redwood are ACUSON Redwood (K210743) and ACUSON Sequoia (K232145) with regards to intended use, indications for use, technological characteristics (transducers, accessories, software features), safety, and effectiveness.

The submission device differs from the predicate/reference devices as follows:

. The addition of 9C2 transducer, which is substantially equivalent to 9C2 transducer previously cleared on the ACUSON Sequoia (K232145).
. The addition of Auto IMT (Intima-Media Thickness) feature, which is substantially equivalent to Auto IMT feature previously cleared on the ACUSON Sequoia (K232145).
. The addition of Virtual Touch UDFF (Ultrasound-Derived Fat Fraction) feature, which is substantially equivalent to Virtual Touch UDFF feature previously cleared on the ACUSON Sequoia (K232145).
. The addition of TCD (Transcranial doppler) Imaging, which is substantially equivalent to TCI previously cleared on the ACUSON Sequoia (K232145).
. The modified ACUSON Redwood Ultrasound System updated the indications for use statement (Intended use) to add Virtual Touch UDFF (Ultrasound-Derived Fat Fraction) indication and Transcranial clinical application for TCD which were previously cleared on the reference device, ACUSON Sequoia (K232145) where transcranial application was covered by Adult Cephalic.
. The addition of needle quides for 9C2 transducer and 9VE4 transducer, which are substantially equivalent to needle guides for 9C2 transducer and 9VE4 transducer previously cleared on the ACUSON Sequoia (K232145).
. The addition of Adult Cephalic and Abdominal clinical applications on 5V1 transducer and Neonatal Cephalic clinical application on 8V3 transducer, which is substantially equivalent to clinical applications of 5V1, 4V1 and 8V3 transducer previously cleared on the ACUSON Sequoia (K232145).

All other hardware and software features of the ACUSON Redwood Diagnostic Ultrasound devices remain unchanged. The foundation of the ACUSON Redwood (this submission) is the ACUSON Redwood (K210743) hardware. ACUSON Redwood (this submission) reuses software developed for ACUSON Redwood (K210743) and adds features such as 9C2 transducer, Auto IMT, Virtual Touch UDFF (Ultrasound-Derived Fat Fraction), TCD from ACUSON Sequoia (K232145).

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7. Nonclinical Data

The subject devices have been evaluated for acoustic output, biocompatibility, cleaning and disinfection effectiveness as well as thermal. electrical, electromagnetic and mechanical safety and have been found to conform to applicable medical device safety standards. The systems comply with the following voluntary standards:

I IEC 62359: Edition 2.1 2017-09. Ultrasonics - Field characterization - Test methods for the determination of thermal and mechanical indices related to medical diagnostic ultrasonic fields / Combines IEC 62359 (2010-10) and AMD 1 (2017-09)
AAMI ES60601-1:2005/(R)2012 and A1:2012, C1:2009/(R)2012 and A2:2010/(R)2012 . (Consolidated Text) Medical electrical equipment - Part 1: General requirements for basic safety and essential performance (IEC 60601-1:2005)
י IEC 60601-1:2005/A1(2012), Medical electric equipment – Part 1: General requirements for basic safety and essential performance / This document and its separate amendments continue to be valid together with the consolidated version
. IEC 60601-1-2 Edition 4.0 2014-02, Medical electrical equipment - Part 1-2: General requirements for basic safety and essential performance - Collateral Standard: Electromagnetic disturbances - Requirements and tests
I IEC 60601-2-18: Edition 3.0 2009-08, Medical electrical equipment - Part 2-18: Particular requirements for the basic safety and essential performance of endoscopic equipment
. IEC 60601-2-37 Edition 2.1 2015, Medical electrical equipment - Part 2-37: Particular requirements for the basic safety and essential performance of ultrasonic medical diagnostic and monitoring equipment
ISO 10993-1 Fifth edition 2018-08, Biological evaluation of medical devices Part 1: I Evaluation and testing within a risk management process
. IEC 60601-1-6:2010+A1:2013+A2:2020 Medical Electrical Equipment Part 1-6, General Requirements for Basic Safety and Essential Performance- Collateral standard: Usability
I ANSI AAMI ISO 14971: Medical devices- Applications of risk management to medical devices, 2019
. FDA Ultrasound Guidance document, "Marketing Clearance of Diagnostic Ultrasound Systems and Transducers," issued in February 2023 (https://www.fda.gov/media/71100/download) for determining the measurement accuracy

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8. Clinical Data

Summary of Clinical Tests

Since the ACUSON Redwood Diagnostic Ultrasound Systems use the same technology and principles as existing predicate device, clinical studies were not required to support substantial equivalence.

UDFF Study Summary

Ultrasound-Derived Fat Fraction (UDFF) is a software tool that measures tissue in a selected region of interest and reports an index for assessing fat content in the liver. UDFF can be useful as an aid to a physician managing adult patients with hepatic steatosis.

The 5C1 transducer on the ACUSON Redwood Ultrasound System is compatible with the UDFF option. The UDFF feature in the ACUSON Redwood Ultrasound System (functionality, algorithms for UDFF measurements and calculations, implementation, etc.) is identical (remains unchanged) when compared to the UDFF feature in the reference device.

Two different studies were conducted to evaluate the performance of the UDFF feature on the ACUSON Redwood Ultrasound System. The demographic distribution of the study population in the two different studies are presented in the following table:

Study 1	Study 2
N= 30 subjects	N= 28 subjects
Ethnicity/Country	Ethnicity/Country
USA = 15	Korea = 28
Korea = 15
Sex	Sex
Male = 15	Male = 20
Female = 15	Female = 8
Age (years)	Age (years)
Mean ±SD = 41.1 ± 18.5	Mean ±SD = 43.8 ± 18.0
Range = 6 - 76	Range = 19 - 74
BMI (kg/m²)	BMI (kg/m²)
Mean ± SD = 27.2 ± 6.8	Mean ± SD = 27.2 ± 2.7
Range = 11 - 44	Range = 23 - 33

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The study details and results are presented in the following table:

Study #	Study Objective	Evaluation Criteria	Results
1	To verify the correlationbetween the performance ofthe UDFF feature onACUSON Redwood (subjectdevice) and the UDFF featureon ACUSON Sequoia(reference device)	Significance level p-Value< 0.05 in a two-tailed test	Pearson Correlationcoefficient betweenUDFF on ACUSONRedwood and ACUSONSequoia was 0.98, andthe difference is notstatistically significant(p=0.792 and t-statistic =-0.263).
	To verify the clinical reliabilityof the UDFF feature on theACUSON Redwood System	Test-retest ICC greaterthan 0.75	ICC = 0.98. The reliabilityof the UDFF feature onACUSON Redwood isconsidered excellent.
	To record the UDFFmeasurement acquisition time	Exam time less than 60seconds	All subjects acquisitiontime was within 22seconds.
2	To verify that UDFF ofACUSON Redwood showsgood agreement with MRI-PDFF	Absolute mean differenceless than 5 percentagepoints and Bland-Altmanlimits of agreement within±15 percentage points	Redwood UDFF andMRI's PDFF had Bland-Altman limits ofagreement between -3.1to 6.3 percentage pointswith a mean absolutedifference of 1.59percentage points.
	To verify the clinical accuracyof the ACUSON RedwoodUDFF feature as comparedto MRI- PDFF	AUROC greater than 0.80	Performance of UDFF onACUSON Redwoodshowed strongperformance ascompared to MRI-PDFFwith AUROC > 0.85.

9. Summary

Intended uses and other key features of the subject device are consistent with traditional clinical practice and FDA guidelines. The design and development process of the manufacturer conforms to 21 CFR 820 Quality System Regulation and ISO 13485:2016 quality system standards. The product is designed to conform to applicable medical device safety standards and compliance is verified through independent evaluation with ongoing factory surveillance. Diagnostic ultrasound systems have accumulated a long history of safe and effective performance. Therefore, it is the opinion of Siemens Medical Solutions USA. Inc. that the ACUSON Redwood system is substantially equivalent with respect to safety and effectiveness to the predicate device.

Regulation Number and Section

§ 892.1550 Ultrasonic pulsed doppler imaging system.

(a)
Identification. An ultrasonic pulsed doppler imaging system is a device that combines the features of continuous wave doppler-effect technology with pulsed-echo effect technology and is intended to determine stationary body tissue characteristics, such as depth or location of tissue interfaces or dynamic tissue characteristics such as velocity of blood or tissue motion. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.