Gamma and beta intra-operative imaging probes

Hoffman, Edward J.; Tornai, Martin P.; Levin, Craig S.; MacDonald, L.R.; Siegel, Stefan

doi:10.1016/s0168-9002(97)00247-7

Cited by 38 publications

(14 citation statements)

References 12 publications

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“…Such small gamma cameras may be useful for imaging small organs such as thyroid and sentinel node as well as for scintimammography applications [5][6][7][8][9] or radio-guided surgery. 10 Here we describe a small portable and low cost gamma camera designed and built at our laboratory. The minigamma camera has an overall size of 90 mm diameter and 200 mm length with a total weight of 2 kg.…”

Section: Introductionmentioning

confidence: 99%

Design and tests of a portable mini gamma camera

et al. 2004

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Design optimization, manufacturing, and tests, both laboratory and clinical, of a portable gamma camera for medical applications are presented. This camera, based on a continuous scintillation crystal and a position-sensitive photomultiplier tube, has an intrinsic spatial resolution of approximately 2 mm, an energy resolution of 13% at 140 keV, and linearities of 0.28 mm (absolute) and 0.15 mm (differential), with a useful field of view of 4.6 cm diameter. Our camera can image small organs with high efficiency and so it can address the demand for devices of specific clinical applications like thyroid and sentinel node scintigraphy as well as scintimammography and radio-guided surgery. The main advantages of the gamma camera with respect to those previously reported in the literature are high portability, low cost, and weight (2 kg), with no significant loss of sensitivity and spatial resolution. All the electronic components are packed inside the minigamma camera, and no external electronic devices are required. The camera is only connected through the universal serial bus port to a portable personal computer (PC), where a specific software allows to control both the camera parameters and the measuring process, by displaying on the PC the acquired image on "real time." In this article, we present the camera and describe the procedures that have led us to choose its configuration. Laboratory and clinical tests are presented together with diagnostic capabilities of the gamma camera.

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Section: Introductionmentioning

confidence: 99%

Design and tests of a portable mini gamma camera

et al. 2004

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“…In this context, many laboratories and companies have developed hand-held g-cameras with different technologies (8)(9)(10)(11)(12)(13)(14)(15). Some of them have been evaluated in different clinical applications such as parathyroid imaging (16)(17)(18)(19), brain (20), bone tumors (21,22), and SNB procedures in BC (21,(23)(24)(25)(26)(27)(28)(29)(30) and more recently in melanoma and gynecologic cancers (31), head and neck cancers (32), and prostate (33) or other urologic cancers (34).…”

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confidence: 99%

The Usefulness of a Preoperative Compact Imager, a Hand-Held γ-Camera for Breast Cancer Sentinel Node Biopsy: Final Results of a Prospective Double-Blind, Clinical Study

Kerrou

Pitre²,

Coutant³

et al. 2011

J Nucl Med

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The aim of this study was to compare the effectiveness of a hand-held preoperative compact imager (POCI) camera with conventional lymphoscintigraphy using a g-camera for sentinel lymph node (SLN) detection in breast cancer. Methods: The main objective was to demonstrate the noninferiority of the POCI relative to conventional lymphoscintigraphy and to compare the number of SLNs detected by the 2 imaging devices. Our study, a clinical prospective, double-blind, noninferiority study, planned to include 200 patients with early breast cancer and started in January 2006. A standard SLN protocol (4 periareolar injections of 37 MBq of 99m Tc-nanocolloids, 2 h before lymphoscintigraphy) was performed preoperatively using a conventional g-camera and then the POCI camera. Scans were obtained by 2 different nuclear medicine physicians unaware of each other's results. The day after, in the operating room, the surgeon, after receiving the previous results, used the counting probe for surgical SLN biopsy. The number and localization of axillary SLNs obtained by lymphoscintigraphy and the POCI and the duration of the whole procedure were determined. Results: Among the 162 patients included, 138 were evaluable. The POCI detected more SLNs than did lymphoscintigraphy in 50 patients (36%), the same number of in 54 patients (39%), and fewer SLNs in 34 patients (25%), representing 84 (61%) discordant pairs. The noninferiority of preoperative compact imaging of axillary SLNs numbers was found to be statistically significant (95% confidence interval, 30%-52%, P 5 0.025) using the McNemar test. The duration of acquisition was shorter using the POCI (,10 min in 84% [n 5 117] of patients; mean, 7.5 6 3.3 min) than lymphoscintigraphy (13% [n 5 18] of patients; mean, 15.7 6 3.4 min), with P , 0.001 using the McNemar test for paired proportions. Conclusion: Preoperative compact imaging using a hand-held camera was able to predict the number and localization of breast cancer SLNs and was not inferior to conventional lymphoscintigraphy in this study. Further studies will determine whether preoperative compact imaging could replace lymphoscintigraphy, especially in surgical centers without an on-site nuclear medicine department. Thedi sease status of the axillary lymph nodes (LNs) is the most significant prognostic factor for patients with early-stage breast cancer (BC) (1). Thus, reliance on histologic examination of the LNs remains the most accurate method for assessing spread of disease-important not only for staging and prognosis but also for treatment selection guiding (1). For many years, the use of sentinel lymph node (SLN) identification and a sampling procedure referred to as sentinel node biopsy (SNB) has progressively reduced the need for axillary lymph node dissection (2) and avoided its associated morbidity. This procedure has now become practiced worldwide (3).Currently, dual detection of SLN with blue dye and radioactive colloids is considered the reference method (4,5). Dual detection not only improves the detection rate (estim...

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“…Photostimulable phosphor plates can store the deposited energy of electrons, and an image is later read out digitally by laser scanning. Intraoperative b-imaging probes have recently been developed using scintillators; Hoffman et al described one based on a microcolumnar CsI(Tl) scintillator and a fiberoptic bundle (15).…”

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confidence: 99%

Direct Imaging of Radionuclide-Produced Electrons and Positrons with an Ultrathin Phosphor

et al. 2008

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Current electron detectors are either unable to image in vivo or lack sufficient spatial resolution because of electron scattering in thick detector materials. This study was aimed at developing a sensitive high-resolution system capable of detecting electronemitting isotopes in vivo. Methods: The system uses a lenscoupled charge-coupled-device camera to capture the scintillation light excited by an electron-emitting object near an ultrathin phosphor. The spatial resolution and sensitivity of the system were measured with a 3.7-kBq 90 Y/ 90 Sr b-source and a 70-mm resin bead labeled with 99m Tc. Finally, we imaged the 99m Tcpertechnetate concentration in the mandibular gland of a mouse in vivo. Results: Useful images were obtained with only a few hundred emitted b particles from the 90 Y/ 90 Sr source or conversion electrons from the 99m Tc bead source. The in vivo image showed a clear profile of the mandibular gland and many fine details with exposures of as low as 30 s. All measurements were consistent with a spatial resolution of about 50 mm, corresponding to 2.5 detector pixels with the current camera. Conclusion: Our new electron-imaging system can image electron-emitting isotope distributions at high resolution and sensitivity. The system is useful for in vivo imaging of small animals and small, exposed regions on humans. The ability to image b particles, positrons, and conversion electrons makes the system applicable to most isotopes. Di rect imaging of electron emissions from radionuclides is valuable in biodistribution and microdosimetry studies, but most current electron detectors are unable to image in vivo because of either the physical configuration or insufficient sensitivity. Others have either compromised spatial resolution or limited sensitivity due to their design tradeoffs; thin detector materials lack sensitivity, and thick materials cause sufficient scatter of the electrons to impair resolution.Film-based autoradiography is capable of micrometerscale resolution because of the thin emulsions used, but film is limited by its narrow linear response range and relatively low sensitivity, requiring long exposure times. Digital autoradiography systems improve linearity and sensitivity over film with a variety of thicker detector materials.Arrays of gas detectors with dedicated readout electronics can provide spatial information (1-4). One of the better systems, the Beta Imager 2000 (LabLogic Systems Limited), has been reported to achieve 100-to 300-mm resolution.Double-sided silicon detectors with orthogonal readout electrodes can achieve 115 mm in full width at half maximum (FWHM) (5). Other solid-state detectors used for this application include charge-coupled devices (CCD), complementary metal-oxide semiconductor arrays, and hybrid detector technologies (6-8). Their limited sensitivity usually requires tens of hours per exposure.Scintillators and phosphors can be used in combination with digital light sensors such as CCD and complementary metal-oxide semiconductor cameras. One approach to achiev...

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Gamma and beta intra-operative imaging probes

Cited by 38 publications

References 12 publications

Design and tests of a portable mini gamma camera

Design and tests of a portable mini gamma camera

The Usefulness of a Preoperative Compact Imager, a Hand-Held γ-Camera for Breast Cancer Sentinel Node Biopsy: Final Results of a Prospective Double-Blind, Clinical Study

Direct Imaging of Radionuclide-Produced Electrons and Positrons with an Ultrathin Phosphor

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