Sonda de THz Integrada em Chip para aplicações de saúde minimamente invasivas

As mentioned previsouly, cancer is still a majour cause of death worlwide, where the tumour ressection is one option to increase the lifetime of a patient. We propose to deliver a tool that will allow higher accuracy and less risk for patients and surgeons. The goal is to deliver a probe, equiped with a THz steerable antenna, with a size that can be integrated on the tip of a common surgical tool. Despite its possible to use THz waves to classify tumoral tissues [14, 15], with possibility of high spatial and temporal resolution and 3D information, the nowadays solutions are based on large benchtop setups (e.g. , fig. 5 of ref [14]), that are not suitable to use on a probe that can be handled by a surgeon intraoperatively. The best surgeons can do nowadays are to use high-frequency ultrasounds, where the resolution is poorer, and the probes are still rather large to go close to the tumor. This proposal goal is to deliver a THz microfabricated probe (3 x 3 x 3 mm3), that allows high sub-millimeter spatial resolution, and real time signal acquisition to allow time resolution similar to an ultrasound device. We consider to be facing relevant challenges since the proposal will deliver a new method for real time imaging of tumor, that will contribute to increase the patient survival rate. As well, such probe may also be used as a new tool to allow the real time assessment of tumoral tissue in procedures where a catheter is allowed to go inside the patients. Moreover, in a future where the THz sources may be enough miniaturized, this probe can be considered to be on-board of endoscopic capsules, allowing to have an extra option for tumoral cells analysis, with the possibility to have depth information. This proposal is ambitious since it will require to go beyond the state of the art in different aspects: - THz probe miniaturization, - Boundary detection of tumoral cells using THz waves. To achieve a probe with a desired size of 3 x 3 x 3 mm3 (the order of magnitude that would allow the easy integration of surgical tools), will require to design a THz antenna array (we propose 1 THz, due to our current work on this frequency), where each patch of the array antenna will be around 32 x 32 um2. Together with the steering antenna, we will need to place one solution to generate on-chip THz radiation. That may be achieved by feeding the probe with optical waveguides to excite and read the radiation at a photoconductive antenna or use some photo mixing solution [14]. As far as we are aware, the generation of controlled THz radiation triggered by an antenna at a tip of an optical fiber is still a huge challenge, and it will be a breakthrough when achieved. Nowadays, we already have sources and detectors with enough power to obtain information from a tissue [14], but such solutions were always implemented as benchtop solutions. The beam steering will be supported by a movable MEMS platform. Steering MEMS structures is a well-known technique, but it need now to emit THz radiation. Finally, despite there are a few techniques available to detect tumor contours, as far as we now, such solutions are not available at THz. In fact, it is difficult to find data about brain tissue, or tumoral tissues at THz. Despite each individual challenge, the cross challenge between telecommunication technologies and medical needs has a high potential to contribute to innovative solutions, that will transform the medical procedures for tumoral surgeries.