CONVERGENCE CDR FOR HITACHI SPECTRADIGITAL V250DSP GAMMA CAMERAS
K991535 · Hitachi Medical Corp. of America · KPS · Jul 30, 1999 · Radiology
Device Facts
Record ID
K991535
Device Name
CONVERGENCE CDR FOR HITACHI SPECTRADIGITAL V250DSP GAMMA CAMERAS
Applicant
Hitachi Medical Corp. of America
Product Code
KPS · Radiology
Decision Date
Jul 30, 1999
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 892.1200
Device Class
Class 2
Indications for Use
Acquisition of patient specific biodistribution of positron-emitting radioisotopes in-vivo. Acquisition of patient specific anatomic density via transmission imaging to determine attenuation coefficients applicable to emission slice data. Reformation of coincidence data to images frames with subsequent reconstruction of transmission and Wholebody ECT data via FBP and/or ML-EM/OSEM reconstruction methods. Analysis and generation of attenuation maps and coefficients to apply to emission ECT slice/volume sets. All SPECT procedures in common practice including matrix based spatial framed, temporal/spatial list mode and angular projection mode static, gated and multi-orbit sampling. Use in conjunction with FDA approved 511 keV emitting radiopharmaceuticals. High and normal count-rate dynamic and non-temporal ECT. In conjunction with Coincidence based imaging, the detector performance and NUA acquisition and processing characteristics are available for non-uniform attenuation ECT, attenuation correction in CID and CID based ECT imaging. Multiple window sampled imaging, including scatter correction via single, dual or plural window processing.
Device Story
Convergence CDR is a Coincidence Imaging Device (CID) option for Hitachi SPECTRADigital V250DSP Gamma Cameras. It enables 511 keV coincidence event detection, transmission imaging, and tomographic reconstruction. Hardware includes aperture grids with graded absorbers (lead, copper, steel) to restrict scatter/randoms, high-speed pre-amps, and coincidence timing circuitry. System acquires emission and transmission data; transmission data uses an external radioactive line source. Software performs FORE (Fourier Rebinning), OSEM (Ordered Subset Expectation Maximization), and FBP (Filtered Back-Projection) reconstruction. Clinicians use the system to generate attenuation-corrected images, improving quantification accuracy by accounting for tissue density. Used in clinical settings by nuclear medicine staff; output assists in diagnostic imaging of positron-emitting radiopharmaceuticals.
Clinical Evidence
Bench testing only. Performance verified using Data Spectrum Delum 5000 Phantom, Data Spectrum PET Phantom, and NEMA Scatter Phantom. Testing confirmed proper operation of transmission reconstruction, attenuation coefficient determination, and coincidence event processing. Clinical tests documented effective application and results consistent with predicate devices.
Technological Characteristics
Coincidence Imaging Device (CID) using NaI(Tl) scintillators (optional 5/8"). Features aperture grids (isotropic solid angle restrictors) and graded absorber plates (1.0mm Lead, 0.5mm Copper, 1.0mm Steel). Employs DSP-based decoding, high-speed pre-amps, and coincidence timing (30-50 nS). Reconstruction via FORE rebinning, OSEM, and FBP. Connectivity includes list mode streaming to workstation. Transmission source: 1.5-3mm diameter line source.
Indications for Use
Indicated for patients undergoing SPECT or coincidence imaging procedures using 511 keV emitting radiopharmaceuticals for the acquisition of biodistribution data and anatomical density mapping for attenuation correction.
Regulatory Classification
Identification
An emission computed tomography system is a device intended to detect the location and distribution of gamma ray- and positron-emitting radionuclides in the body and produce cross-sectional images through computer reconstruction of the data. This generic type of device may include signal analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component parts, and accessories.
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JUL 30 1999
Image /page/0/Picture/1 description: The image contains a sequence of handwritten characters. The sequence starts with the letter 'K', followed by the numbers '991535'. The numbers are written in a cursive style, with some of the digits connected to each other.
# Attachment 1 Summary of Safety and Effectiveness
*Attachments labeled "CONFIDENTIAL" as follows: Hitachi Medical Corporation regards the information defined as part of this Attachment to be a trade secret and confidential in nature.
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### 1.0 Submitter Information
Hitachi Medical Corporation of America Nuclear Medicine Product Division 9177 Dutton Drive, Twinsburg, Ohio ESTABLISHMENT REGISTRATION NUMBER: 1530450 PH: 330-405-3330 FX: 330-405-3222
Contact Garv W. Enos
Date
April 30. 1999
### 2.0 DEVICE NAME: Convergence SM CDR SM
Classification Panel: Radiology Classification Name: System, Tomographic, Nuclear Classification Number: 892.1200 90KPS Trade/Proprietary Name: Convergence SMCDR SM for Hitachi SPECTRADigital™ V250DSP Gamma Cameras
Predicate Device: ADAC EPIC-MCD cleared under K952684. ADAC MCD-AC cleared under K971980 and ADAC VERTEX Ultra cleared under K982911.
### 3.0 Device Description
# Function
CONVERGENCE®M CDR §™ for Hitachi SPECTRADigital™ V250DSP Gamma Cameras, cleared under K954129 is an Coincidence Imaging Device (CID) option that provides capability to acquire 511 keV coincidence events and form images in 1D, 2D and 3D modes of operation. With the addition of ATTCOR, non-linear scaled low energy transmission correction utilizing NUA88 submitted under K991318) mapping of anatomical information using external radioactive line source transmission with analysis of densities and assignment of patient specific attenuation coefficients to minimize distortion due to overlying tissue and undesired scattered photons. The device is a combination of hardware and software to provide detection, decoding, image formation with corrections and Whole body and tomographic reconstruction. When the system is equipped with thicker 5/8" crystals submitted under K991129, the V250DSP efficiency for 511 keV events is improved.
The additional Hardware which consists of Aperture Grids with graded absorbers, high speed pre-amps with coincident signal timing, high speed decoding and correction circuitry and acquisition control software. 1-D framing at the camera system is provided and 2-D, 3-D frame formation via workstation based FORE (Fourier Rebinning) and OS-EM processes. When equipped with ATTCORSM, a single, non-moving line source holder equipped with shutter, special line source slat
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collimation to minimize patient exposure and axial scatter and non-linear scaling processing is provided. The software consists of FORE rebinning. OSEM iterative and/or FBP (Filtered Back-Projection) reconstruction, transmission acquisition control and coefficient determination in the correction to ECT slice data per NUASM submitted under K991318. A detailed description can be found in Attachment 1. Detailed device specifications can be found in Attachment 4.
# Scientific Concepts:
Coincidence detection with large field of view crystal devices is not new, dating to the late 1960's. Publications by Muehllehner and Jaszczak in the early 1970's cited Positron Imaging utilizing plural coincidence detector channels and graded radiation absorbers. Recent development of higher performance "multi-range" pre-amplification and digital decoding has combined with new rebinning algorithms to provide reasonable 511 keV image reformation efficiency.
lmproved baseline restoration and pile-up reiection circuits have become part of the pre-digitization of PMT signals, permitting digitizers and DSP (digital signal processor) based decoding to operate on higher quality and data rate signals rising from 511 keV events. With the addition of pre-digitization coincidence determination (30~50 nS timing), signal integration and decoding is limited to qualified events to maximize efficiency.The use of DSP based corrections (linearity, uniformity, energy) maximizes signal processing at higher singles and coincident count rate performance.
To maximize countrate and minimize randoms/scatter, the use of graded absorber plates (Lead-1.0mm, Copper-0.5mm, Steel-1.0mm layers) prior to crystal entrance, ensures count processing to energies above 300keV and reduces associated off axis oblique and randoms scatter. Further, to reduce axial emissions and reduce random events, Aperture Grids (isotropic solid angle restrictors) fixed to the detectors act in a similar manner to extended septa in dedicated PET devices. The utility of CFD (delay timing windows @ 200nS-300nS) are used to differentiate TRUE coincidence from Randoms.
511 keV event detection is more efficient in thicker Nal(TI), which has established growing interest in the option of 5/8" scintillators (optional to 3/8" which are standard in most systems and submitted for SPECTRADigital V250DSP under K991129.
Coincidence events in 1D (perpendicular to both detectors) are framed by the camera system without need for external rebinning. In 2D and 3D modes, the camera event processes are list mode streamed and subjected to FORE (First Order Fourier Rebinning Approximation) for framing. Subsequent processing for tomographic, WholeBody and correction of attenuation effects are managed with well documented OS-EM and attenuation mapping routines (submitted for SPECTRADigital V250DSP under K991318. The non-linear scaled low energy transmission maps to 511 keV application, however the effect and basis is similar to NUASM submitted under K991318.
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The Convergence™ CDR3M for Hitachi SPECTRADigital™ V250DSP Gamma Cameras is a Coincidence Imaging Device (CID) option that provides capability to acquire 511 keV coincidence events and form images in 1D. 2D and 3D modes of operation.
### 5.0 Device Technological Characteristics:
Technologies associated with Convergence®M CDR®M for Hitachi SPECTRADigital™ V250DSP Gamma Cameras are defined in Attachment 4. Key elements include:
- � Aperture Grids to restrict incident angle of coincidence, scatter and randoms in 1D. 2D and 3D operation.
- ◆ Graded Absorber Plates for removal of oblique and scattered photons.
- New designed pre-amps, decoder and correction circuits to provide . coincidence/random timing and discriminated signals for integration. Camera system framing in 1D and List mode event description in 2D and 3D are transformed via FORE rebinning for additional processing.
- ♦ Axial collimated low energy line source of NRC registered and approved sources in the 1.5~3mm diameter range
- Utilization of offset fan beam parameters and detector/collimator orientation to � minimize truncation and increase viewing volume utilizing the Aperture Grids (increase the TCT FOV).
- � Sequentially acquired Transmission and Emission data to minimize cross contamination
- � Scatter window sampling to modulate transmission and emission data as part of the reconstruction domain.
- � OSEM iterative reconstruction of transmission and emission data to maximize resolution and quantification accuracy.
- � Segmentation of anatomical regions and anatomical densities to correct attenuation effects in emission SPECT.
### 6.0 Testing and Equivalence
In the code implementation, simulation and phantom processed studies, acquisition, analysis and correction results have been thoroughly tested and verified to operate properly and as intended. The results of transmission reconstruction and attenuation coefficient determination has proven effective. Clinical tests have documented effective application and expected results consistent with predicate devices currently in commercial distribution.
Hitachi Medical believes the ConvergencesM CDRSM for Hitachi SPECTRADigital™ V250DSP Gamma Cameras, a Coincidence Imaging Device (CID) option, to be substantially equivalent to Gamma Camera Systems currently in commercial distribution in the U.S. We have tested the Convergence SM CDR SM for Hitachi SPECTRADigital™ V250DSP Gamma Cameras with the Data Spectrum Delum 5000 Phantom, Data Spectrum PET Phantom, and NEMA Scatter Phantom to establish the basis for proper operation.
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In accordance with NUREG-1556 of the Nuclear Regulatory Commission for emitter source devices, the devices emissions, leakage, patient dose and safe controls are consistent with requirement and those of commercially approved devices.
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# DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health Service
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### JUL 30 1999
Gary W. Enos Hitachi Medical Corporation of America Nuclear Medicine Products Division 9177 Dutton Drive Twinsburg, Ohio 44087
Re:
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
K991535 CONVERGENCE CDR Coincidence Detection Reconstruction for Hitachi SPECTRA Digital™ V250DSP Digital Dual Detector Gamma Camera System Dated: April 30, 1999 Received: May 4, 1999 Regulatory Class: II 21 CFR 892.1200/Procode: 90 KPS
Dear Mr. Enos:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we 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). 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 either class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
This letter will allow you to begin marketing your device as described in your 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 Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4613. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification"(21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".
Sincerely yours,
CAPT Daniel G. Schultz, M.D. Acting Director, Division of Reproductive, Abdominal, Ear, Nose and Throat, and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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510(k) Number (if known): K 991535
Convergence®M CDR®M for Hitachi SPECTRADigital™ V250DSP Device Name: Gamma Cameras
Indications For Use:
Intended uses of Convergence™ CDR®M for Hitachi SPECTRADigital™V250DSP Gameras is identical to the principle of coincidence imaging used by EPIC-MCD Cleared under K952684, ADAC MCD-AC cleared under K971980 in intended use, methods, reconstruction algorithms, transmission source type, and effectiveness of application. These include:
- Acquisition of patient specific biodistribution of positron-emitting � radioisotopes in-vivo.
- Acquisition of patient specific anatomic density via transmission imaging to � determine attenuation coefficients applicable to emission slice data.
- Reformation of coincidence data to images frames with subsequent � reconstruction of transmission and Wholebody ECT data via FBP and/or ML-EM/OSEM reconstruction methods.
- Analysis and generation of attenuation maps and coefficients to apply to � emission ECT slice/volume sets.
Convergence sm for for Hitachi with Imaging capabilities SPECTRADigital™ V250DSP Gamma Cameras option include:
- All SPECT procedures in common practice including matrix based spatial ■ framed, temporal/spatial list mode and angular projection mode static, gated and multi-orbit sampling
- Use in conjunction with FDA approved 511 keV emitting I radiopharmaceuticals
- High and normal count-rate dynamic and non-temporal ECT 회
- In conjunction with Coincidence based imaging, the detector I performance and NUA® acquisition and processing characteristics are available for non-uniform attenuation ECT, attenuation correction in CID and CID based ECT imaging.
- Multiple window sampled imaging, including scatter correction via 트 single, dual or plural window processing.
(Please do not write below this line-continue on another Page if needed)
Concurrence of CDRH, Office of Device Evaluation (ODE)
| Prescription Use | ✓ | OR | Over-The-Counter Use _____ |
|----------------------|---|----|----------------------------|
| (Per 21 CFR 801.109) | | | |
Wind h. Glynn
| (Division Sign-Off) | (Optional Format 1-2-96) |
|--------------------------------------------------------------------|--------------------------|
| Division of Reproductive, Abdominal, ENT, and Radiological Devices | |
| 510(k) Number | <u>K991535</u> |
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