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arXiv · 2504.05884

Endoscopic fiber-coupled diamond magnetometer for cancer surgery

A. J. Newman·S. M. Graham·C. J. Stephen·A. M. Edmonds·M. L. Markham·G. W. Morley
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Abstract

Interoperative measurements using magnetic sensors is a valuable technique in cancer surgery for finding magnetic tracers. Here we present a fiber-coupled nitrogen-vacancy (N-V) center magnetometer capable of detecting iron oxide suspension (MagTrace from Endomagnetics Ltd.) used in breast cancer surgeries. Detection of an iron mass as low as 0.56~mg has been demonstrated, 100 times less than that of a recommended dose at a maximum distance of 5.8~mm. Detection of an iron concentration as low as 2.8 mg/ml has also been demonstrated, 20 times less than a recommended dose. The maximum working distance from the sensor can be as large as 14.6~mm for higher concentrations. The sensor head has a maximum diameter of 10~mm which would allow it to be used for endoscopy, laparoscopy and interoperative surgery.

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A. J. Newman, S. M. Graham, C. J. Stephen, A. M. Edmonds, M. L. Markham, G. W. Morley. 2025-04-08. Endoscopic fiber-coupled diamond magnetometer for cancer surgery. https://doi.org/10.1103/znt3-988w

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