- Split View
-
Views
-
Cite
Cite
Melanie Schweitzer, Mihaela Stavarache, Nicholas Petersen, Spyridon Bakas, Apostolos John Tsiouris, Christos Davatzikos, Michael G Kaplitt, Mark M Souweidane, SCDT-37. MODULATION OF CONVECTION ENHANCED DELIVERY (CED) DISTRIBUTION USING FOCUSED ULTRASOUND (FUS), Neuro-Oncology, Volume 19, Issue suppl_6, November 2017, Page vi272, https://doi.org/10.1093/neuonc/nox168.1118
- Share Icon Share
Abstract
Ineffective drug delivery across the blood brain barrier (BBB) is one purported factor that contributes to the lack of therapeutic benefit of systemic chemotherapy for brain tumors. Convection enhanced delivery (CED) is an appealing form of therapeutic drug delivery to the brain that bypasses the BBB while avoiding systemic toxicity. When considering highly diffuse and infiltrative tumors, adequate tumor coverage might not always be possible. Catheter design, infusion parameters, and multi-centric targeting have all been explored as means to alter distribution following CED. The ability to actively modulate infusion volume would be an appealing feature of a CED-based platform. We hypothesize that magnetic resonance-guided focused ultrasound (MRgFUS) may provide a means for modulating CED distribution.
A combination of contrast agent (Gd-Magnevist) mixed with Methylene Blue Dye was stereotactically injected into a pre-determined location within the brain of naïve Sprague-Dawley rats. Pre- and post-injection MRgFUS volumes were acquired to monitor the effects of the FUS and to define the sonication target. An area situated three millimeters posterior to the infusion site was chosen as the sonication target and FUS was applied simultaneously with microbubble administration via a tail vein catheter. Control animals did not undergo sonication, but they received an intra-tail vein injection of microbubbles and all subsequent MRI scans. Animals were sacrificed and their brains harvested for histological analysis. Quantitative volumetric modeling of infusion and percent increase calculations were performed using the Cancer Imaging Phenomics Toolkit (CaPTk).
The average relative volume expansion between pre- and post-injection volumes in the experimental and the control animals were 135.52% and 105%, respectively.
The results confirm that sonication increased the volume of parenchyma covered by infusate. This preliminary work supports the possibility of using MRgFUS to contour distribution patterns during CED in an effort to enhance therapeutic goals.
- magnetic resonance imaging
- ultrasonography
- contrast media
- brain tumors
- chemotherapy regimen
- blood-brain barrier
- drug delivery systems
- dyes
- form perception
- methylene blue
- rats, sprague-dawley
- sonication
- brain
- neoplasms
- vibration
- bypass
- catheters
- toxic effect
- fluid resuscitation
- treatment goals
- mri-guided focused ultrasound ablation
- parenchyma
- infusion procedures
- microbubbles
- convection enhanced delivery of intracerebral catheter(s)
- gadopentetate dimeglumine
- cancer imaging