Dual-mode intracranial catheters for minimally-invasive neuro-oncology feasibility study

In this study, we investigated the feasibility of dual-mode intracranial catheter transducers for visualization and treatment of tumors in the brain. Feasibility is demonstrated in two ways: 1) by developing a 12 Fr, integrated matrix and linear array catheter transducer prototype for combined real-time D imaging and heating, and 2) by testing 3.5 Fr IVUS-catheter-packageable transducers for therapeutic potential. The 3.6 MHz, 12 Fr catheter acquired real-time 3D images of canine brain structures in vivo while placed in the superior sagittal sinus via a burr hole in the skull, and achieved a 3.5°C temperature rise in tissue-mimicking material at a 2 cm focus in vitro. The IVUS-sized prototype transducers were tested for maximum intensity and mechanical index, and a thermal model was used to extrapolate and estimate each transducer's maximum potential temperature rise in brain tissue.