The spatial localization of radioactive sources is currently a very important issue that affects many sectors, including the nuclear industry, homeland security as well as medical imaging. Currently several approaches are used, but the development of technology to detect and characterize the radiation becomes particularly important in diagnostic by imaging. In this area, the radiation detection probes have long been used to guide the surgery, due to their ability to localize and quantify the uptake of radiopharmaceuticals in the tissues, even in depth. Typically a radiolabeled colloid is injected into the tumor, or in proximity to it, and the surgeon uses a portable radiation detector, the gamma probe, to identify the lymph nodes where it is accumulated.
Our goal is to provide a new system for identifying gamma radiations and their direction. Our system is based on using our innovative patent pending technology of the self-guided “scintigraphic goniometric probe” (as briefly GonioProbe). Preliminary analysis demonstrated clearly superior characteristics compared to those of the currently existing products. We believe that these superior characteristics, combined with highly innovative features introduced by our system, will greatly improve the intervention procedures.
The most advanced pre-operative imaging (CT diagnostic techniques, MRI, ultrasound, SPECT, PET, PET/CT) provide the oncologist surgeon increasingly precise information about the location and extent of the neoplastic disease, but do not provide real time information during surgery. Indeed, despite the considerable amount of pre-operative information, during intervention the surgeon continues to rely principally on visual inspection and palpation of the tissue that must be removed to be subjected to biopsy. The inspection and palpation take place directly in the case of classic “open air” intervention, and are mediated by specific instruments in video-assisted surgery.
The radio-guided surgery has added an additional tool to traditional methods used by the surgeon, allowing the identification of the tissue to be removed by means of a preoperative “marking” of the lesion (or suspected such) with a radio pharmaceutical. This practice actually provides the surgeon real-time information on the location and extent of the disease and on the evaluation of surgical resection margins. This then allows the surgeon to minimize surgical invasiveness of many diagnostic and therapeutic procedures ensuring the maximum benefit for the patient.
This method is increasingly prevalent, especially with regard to radio-guided biopsy of the sentinel lymph node (SLN) in patients with breast cancer and malignant melanoma, which are undoubtedly the two most used and proven applications. For both diseases the concept of sentinel lymph node is now recognized by the most popular and used system of staging of cancer, the so-called TNM.
The current methods that exploit radio markers require the combined use of imaging systems and portable gamma probes. The tissue or lymph node which absorbed the radio tracer are identified preoperatively by a lymphoscintigraphy with clinical Gamma Camera or other small field imaging devices; during surgery a portable devices (gamma probe) is instead used for evaluating the signal originating from the area under investigation helping the surgeon to locate quickly and with high accuracy even the smallest node.
Unfortunately all current intraoperative probes for radio-guided surgery provide guidance regarding only a small area of the underlying tissue due to passive collimator (lead or tungsten) positioned above the detector which reduces much the field of view (FOV) and needs a longer time to perform a reliable count. Some models of the gamma probe are made with relatively larger FOV, because deprived of a collimator, but to the detriment of precision in the localization of the absorbing tissue. In both cases it is necessary to manually scan the entire area under investigation by the operator, with consequent lengthening of the time of intervention.
To overcome the limitations due to low efficiency and reduced FOV, Prof. R. Pani has developed at the “Sapienza” University of Rome a device that can provide the operator information not only regarding the underlying tissue, but also about the direction to follow to reach the target, turning the device from a simple and passive radiation counter into an innovative instrument of real time active navigation.
Research conducted by Prof. Roberto Pani led to the filing of the patent of the “Scintigraphic Goniometric Probe” [1], whose exclusive license was obtained by NG Detectors as part of the Start Up agreement between NG Detectors and “Sapienza” University.
Prof. R. Pani is currently a professor at the “Sapienza” University as well as shareholder and Scientific Director of NG Detectors.
[1] Patent:
- R. PANI (2010). Sonda Scintigrafica Goniometrica. RM2010A000082, UNIVERSITA’DEGLI STUDI DI ROMA “LA SAPIENZA” (Italian filing)
- R. PANI (2011). SCINTIGRAPHIC GONIOMETRIC PROBE. PCT/IB2011/050851, UNIVERSITA’ DEGLI STUDI DI ROMA “LA SAPIENZA” (European extention)
- R. PANI (2013). SCINTIGRAPHIC GONIOMETRIC PROBE. US 2013/0053686 A1, UNIVERSITA’ DEGLI STUDI DI ROMA “LA SAPIENZA” (USA filing)