blood-brain barrier

Simultaneous localized brain mild hyperthermia and blood-brain barrier opening via feedback-controlled transcranial MR-guided focused ultrasound and microbubbles

Simultaneous localized brain mild hyperthermia and blood-brain barrier opening via feedback-controlled transcranial MR-guided focused ultrasound and microbubbles IEEE Transactions on Biomedical Engineering (TBME)
We present a synergistic focused ultrasound-based brain drug delivery method for both spatiotemporally precise transcranial mild hyperthermia and simultaneous localized blood-brain barrier (BBB) opening. We demonstrated that with the presence of microbubbles, transcranial MR-guided focused ultrasound mild hyperthermia can be achieved at significantly reduced powers and prolonged BBB opening can be simultaneously achieved with hyperthermia sonications in a rodent model. No structural abnormality, edema, hemorrhage, or acute microglial activation was observed in the target region via MR imaging and histology. This study provides a new strategy for enhanced drug delivery in brain tissues with a high clinical translation potential. read more

Acoustic holograms for bilateral blood-brain barrier opening in a mouse model

Author(s): Elisa E. Konofagou
Acoustic holograms for bilateral blood-brain barrier opening in a mouse model IEEE Transactions on Biomedical Engineering (TBME)
Microbubble-enhanced focused ultrasound (FUS) allows the blood-brain barrier opening (BBBO) for drug delivery into the brain. However, single-element FUS technologies do not allow high-resolution, multi-focal, simultaneous targeting, in addition to distortion of the focused beam due to skull aberrations. In this work, we present the first preclinical BBBO application of acoustic holograms in mice. A 3D-printed hologram coupled to a single-element focused transducer produced two symmetric foci while compensating for the skull aberrations. T1-weighted MRI showed BBBO at two quasi-spherical spots. This work demonstrates the feasibility of hologram-assisted BBBO for low-cost and highly-localized drug delivery in a mouse brain. read more

Contrast-free detection of focused ultrasound-induced blood-brain barrier opening using diffusion tensor imaging

Author(s): Maria Eleni Karakatsani, Antonios Pouliopoulos, Michael Liu, Sachin R. Jambawalikar, Elisa E. Konofagou
Contrast-free detection of focused ultrasound-induced blood-brain barrier opening using diffusion tensor imaging 170 177 IEEE Transactions on Biomedical Engineering (TBME)
Karakatsani et al. report a contrast-free method to detect focused ultrasound (FUS)-induced blood-brain barrier (BBB) opening using diffusion tensor imaging (DTI). The localized BBB opening was hypothesized to result to a transient change in the diffusion pattern of water molecules and was tested in a non-human primate model, which closely resembled the human anatomy. They found that fractional anisotropy within the targeted area increased by 82% after the procedure, showing that DTI can confirm BBB opening without the use of contrast agents, increasing the safety of the methodology since contrast does not have to cross into the brain parenchyma. read more