A Portable γ-Camera for Intraoperative Detection of Sentinel Nodes in the Head and Neck Region

Abstract

We introduced and evaluated a portable g-camera for intraoperative visualization of sentinel nodes in the head and neck region. Methods: Planar lymphoscintigraphy and SPECT/CT were performed after peritumoral injection of 99m Tc-nanocolloid in 25 patients (head and neck melanoma or oral cavity carcinoma). Sentinel nodes were localized intraoperatively with a portable g-camera and a hand-held g-probe. The portable g-camera was used to determine the distribution of remaining radioactivity after excision of the sentinel nodes. Results: The portable g-camera visualized all 70 preoperatively identified sentinel nodes. Sentinel nodes at difficult sites could be localized more efficiently, and in 6 patients, 9 additional nodes (1 tumor-positive) were identified with the portable g-camera after excision. Conclusion: Intraoperative identification of sentinel nodes in the head and neck region with a portable g-camera is feasible and might lead to detection of more sentinel nodes.

Comparing the Hybrid Fluorescent–Radioactive Tracer Indocyanine Green–99mTc-Nanocolloid with 99mTc-Nanocolloid for Sentinel Node Identification: A Validation Study Using Lymphoscintigraphy and SPECT/CT

“…Because the probe has a limited spatial resolution and sentinel nodes do not always stain blue, sentinel nodes can be difficult to localize in areas with a complex anatomy and when sentinel nodes are near the injection site (14,15). Although the incorporation of a portable g-camera in the intraoperative procedure partially addresses these limitations by increasing the detection sensitivity and providing an intraoperative overview image of the radioactive sentinel nodes, this device does not depict the surrounding anatomic structures in the surgical field (16)(17)(18).…”

Portable gamma cameras: the real value of an additional view in the operating theatre

“…Prior SPECT images may be mandatory in head and neck cancer, with images from the PGC being used to guide the surgeon and to make sure that the SN has been completely resected. Vermeeren et al [8] have recently reported an improvement of 24% in SN detection. …”

“…SNs are widely used in breast cancer, melanoma and head and neck cancer, but in the last decade, their use has expanded to additional indications, with more sophistication and complexity in the technique, including indications in urology, gynaecology and gastroenterology. The addition of PGCs has improved the SN technique, particularly when intraoperative tracer injection is needed or in laparoscopic SN localization [7][8][9].In breast cancer, the main indication for a SN procedure worldwide, usually no laparoscopic technique and no intraoperative tracer injection is needed. The utility of the PGC in breast cancer remains only when no conventional gamma camera is available, and in particular in cases with extra-axillary drainage.…”

“…SNs are widely used in breast cancer, melanoma and head and neck cancer, but in the last decade, their use has expanded to additional indications, with more sophistication and complexity in the technique, including indications in urology, gynaecology and gastroenterology. The addition of PGCs has improved the SN technique, particularly when intraoperative tracer injection is needed or in laparoscopic SN localization [7][8][9].…”

Hybrid Surgical Guidance: Does Hardware Integration of γ- and Fluorescence Imaging Modalities Make Sense?

“…Acoustic (and numeric) feedback generated by a g-ray detection probe (GP) can then be used to provide directional guidance during the intervention (4). Alternatively, portable g-imaging modalities can be used to provide an intraoperative image of the nodal uptake (5,6). Despite research-oriented efforts, commercially available portable g-detection modalities do not yet allow depiction of detailed anatomic information (7,8).…”