Although portable gamma cameras (PGCs) have been helpful to depict sentinel nodes (SNs), sometimes nuclear physicians or surgeons have difficulties to interpret PGC images because of the lack of anatomical information. The aim of the present study was to develop and clinically test the prototype of a new portable hybrid camera (PHC), which adds optical to γ-imaging.
In 2 hospitals, the existing PGC (Sentinella S102; Oncovision) was upgraded with an optical module (BB2-08S2C-25; Point Grey Research) to build a PHC. Preoperative PHC overview images (positioned at 15 cm distance) and close-up image (position at <5 cm distance) were obtained from 25 patients (12 melanoma, 2 oral cavity, and 11 breast cancer) after conventional lymphoscintigraphy. Errors in the optical image coregistration were evaluated with a 5-mm accuracy for each patient.
Conventional lymphoscintigraphy and the close-up PHC images depicted 55 SNs in total. In the PHC overview images, the optical module offered fused optical and γ-imaging indicating the image field of view and anatomical SN locations. Average optical image coregistration errors were 1.0 cm (range, 0–2.0 cm).
Fused optical and γ-imaging with the prototype PHC is technically feasible and helpful for the image interpretation. The optical image visualizes the γ-image field of view, enabling SN localization in an anatomical context in a preoperative setting; however, for the operating room, the use of its optical component needs to be additionally adjusted.
From the *Nuclear Medicine Department, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands; †Nuclear Medicine Department. Hospital Clínic Barcelona. Institut d’Investigació Biomèdica August Pi I Sunyer (IDIBAPS), Barcelona, Spain; and ‡Interventional Molecular Imaging, Nuclear Medicine Department, Radiology Department, Leiden University Medical Center, Leiden, The Netherlands.
Received for publication March 20, 2015; revision accepted April 27, 2015.
Conflicts of interest and sources of funding: This study was part of the MSc graduation project of Daan Hellingman. In the period following this study, Daan Hellingman has been affiliated as an independent contractor working for Oncovision. All the other authors declare no conflict of interests.
Daan Hellingman and Sergi Vidal-Sicart shared first authorship.
Ethical Standards: All human studies have been approved by the appropriate ethics committee and have therefore been performed in accordance with the ethical standards in the 1964 Declaration of Helsinki and its later amendments.
Correspondence to: Daan Hellingman, MSc, Plesmanlaan 121 1066 CX Amsterdam, The Netherlands. E-mail: email@example.com.