An OCT-enable Minimally-invasive Neurosurgical Guide for in-situ Brain Monitoring

As many advanced countries, including Taiwan, are beginning to enter the aging society, so the aging diseases such as Parkinson's Disease (PD) will be an inevitable issue in the 21st century. In order to provide a better quality of treatment, the Deep Brain Simulation (DBS) procedure is suggested to be adopted for the neurological treatment. For DBS, the key to the success of the treatment is the DBS stimulation electrode can act at right position, in other words, the electrode must be accurately implanted in the target area. At present, the surgical navigation for DBS relies on the pre-operative CT/MRI and intra-operative MER (microelectrode recording); however, some limitations are found in these methods. Therefore, As the result, an minimally-invasive guiding tool providing real-time localization information is required for assisting physician modifying the path for the safe and precise implantation of electrodes. To meet the unmet needs as mentioned previously, an innovative optical coherence tomography-guided DBS (OCTgDBS) system with a high slender ratio (0.7 mm outer diameter and 30 cm length) of forward-imaging needle is developed without any contrast agent. A 1323 nm swept source laser with 20 kHz A-scan rate and bandwidth of 127 nm is used. The OCTgDBS system performance such as axial resolution is about 6 μm and SNR is up to 81.75 dB. We successfully distinguished the tissue structure of ex vivo swine brain and found that white matter has stronger backscatters and steeper attenuation rate than gray matter. The results demonstrate that the OCTgDBS system is an alternative neurosurgical guiding approach for in-situ brain monitoring.