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Transport and Biomechanics of Convection Enhanced Drug Delivery. Master’s Thesis Defense Dec 7 th, 2010 219 SEO. Nikhil Sindhwani Bioengineering, UIC. Thesis Committee : Prof. Andreas Linninger Advisor Prof. Richard Magin Richard Penn, M.D. Laboratory for Product and Process Design
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Transport and Biomechanics of Convection Enhanced Drug Delivery Master’s Thesis Defense Dec 7th, 2010 219 SEO Nikhil Sindhwani Bioengineering, UIC Thesis Committee: Prof. Andreas Linninger Advisor Prof. Richard Magin Richard Penn, M.D. Laboratory for Product and Process Design Department of Bioengineering University of Illinois at Chicago NS, LPPD, MS Thesis Defense, 2010
Neurologic disorders and current treatment options NS, LPPD, MS Thesis Defense, 2010
Parkinson’s disease: • Affected population: 1.5 million[1] • Symptoms: • Tremors • Dementia • Cause: Gradual loss of dopamine producing nerve cells, mostly in Substantia niagra region. • Current treatment options: • Levodopa: precursor to dopamine. • Surgery that would destroy areas of brain that trigger tremors. • Deep brain stimulation. • Inject viral vector containing GAD gene[2]. [3] [1] WebMD: http://www.webmd.com/parkinsons-disease/guide/parkinsons-disease-treatment-overview [2] Nytimes: http://www.nytimes.com/2003/08/19/science/19GENE.html [3] MedlinePlus: http://www.nlm.nih.gov/medlineplus/ency/imagepages/19515.htm NS, LPPD, MS Thesis Defense, 2010
Huntington’s Disease: • Affected population: 5-10/100,000 persons [1]. • Symptoms: • Dementia, abnormal movements (chorea), irritability, hallucinations[2] . • Cause: • Genetic defect in chromosme #4 producing mutated Huntingtin protein (mHtt). • Loss of striatal small neurons[3]. • Current treatment options[2]: • No cure for HD. • Dopamine blockers like tetrabenzine. • co-enzyme Q10. [4] [1] Driver-Dunckley E, Caviness JN. (2007). "Huntington's disease". In Schapira AHV. Neurology and Clinical Neuroscience. Mosby Elsevier. pp. 879–885.. [2] https://health.google.com/health/ref/Huntington's+disease [3] Huot, P., M. Lévesque, et al. (2007). "The fate of striatal dopaminergic neurons in Parkinson's disease and Huntington's chorea." Brain 130(1): 222-232. [4] http://brainmind.com/BasalGanglia.html NS, LPPD, MS Thesis Defense, 2010
Brain Tumors: • Statistics[1]: • About 22,020 new cases of malignant brain tumors in 2010. • 90% of all brain tumors are gliomas in people above 45 yrs of age. • Survival rate: Roughly 40% • Symptoms[1]: • Differs depending on the region affected, headaches, spasms etc. • Cause: • Mostly genetic • Current treatment options[1]: • Surgery: Craniotomy followed by placement of Gliadel (carmutsine) wafers. • Radiation therapy • Chemotherapy: IV or oral delivery, only a fraction reaches the tumor site. [2] [3] [1] www.cancer.org [2] http://www.mayfieldclinic.com/PE-Glioma.htm [3] www.imagingconsult.com NS, LPPD, MS Thesis Defense, 2010
Blood Brain Barrier Allows only molecules smaller than 400-500 Da to enter. NS, LPPD, MS Thesis Defense, 2010
CNS Disorders Requiring LARGE Molecules Drug Therapy • Alzheimer’s Disease • Parkinson’s Disease • Huntington’s Disease • Autism • Multiple Sclerosis • Brain Cancer • Stroke • Brain Trauma • Lyosomal Storage Disorders • Inherited Ataxias CNS Disorders Treatable With small Drug Molecules • Depression • Schizophrenia • Chronic Pain • Epilepsy NS, LPPD, MS Thesis Defense, 2010
There is a need for a better drug delivery mechanism that can • Deliver to specific target area, • Reduce side effects, and • Bypass the Blood Brain Barrier. Pardridge, 1996 NS, LPPD, MS Thesis Defense, 2010
Convection Enhanced Delivery (CED) • Pressure driven direct intra-parenchymal infusion of drugs using a catheter. • Flow rate can be controlled, providing good control over infusion volume. • Bypasses BBB, so large molecular drugs can be deliveryed. NS, LPPD, MS Thesis Defense, 2010
Convection Enhanced Delivery delivers drugs to a large volume Pressure Driven delivery Interstitial concentration Diffusion Driven delivery [1] Distance [1] Raghavan, R., M. L. Brady, et al. (2006). "Convection-enhanced delivery of therapeutics for brain disease, and its optimization." Neurosurgical FOCUS 20(4): E12. NS, LPPD, MS Thesis Defense, 2010
CED in Clinical Trials: [1] Clinical trials failed because therapeutic levels of drug could not reached target area [1] Bidros, D. S., J. K. Liu, et al. (2010) "Future of convection-enhanced delivery in the treatment of brain tumors." Future Oncology 6(1): 117-125. NS, LPPD, MS Thesis Defense, 2010
Problems addressed in this thesis: NS, LPPD, MS Thesis Defense, 2010
Brain tissue anisotropy and heterogeneity Lateral Ventricles • Complicated geometry, with many internal structures • White matter tracts Caudate nucleus Putamen Corpus Callosum Globus Pallidus Third Ventricle Cortex Hippocampus NS, LPPD, MS Thesis Defense, 2010
Backflow Avoided by using very low flow rates: leading to low drug concentrations Uncontrolled leakage of infusate along the catheter shaft at high flow rates NS, LPPD, MS Thesis Defense, 2010
GOAL To use principles of TRANSPORT and MECHANICS to Explain, Analyze and Improve existing CED protocols NS, LPPD, MS Thesis Defense, 2010
M.S. Thesis Outline NS, LPPD, MS Thesis Defense, 2010
Measurement of concentrations using digital images N. Sindhwani, et al.Methods for determining agent concentration profiles in agarose gel during Convection Enhanced Drug Delivery, IEEE Transactions on Biomedical EngineeringJournal of Biomechanical engineering, Accepted Nov 2010. NS, LPPD, MS Thesis Defense, 2010
Experimental setup NS, LPPD, MS Thesis Defense, 2010
Geometry effect Single port catheter Single port catheter NS, LPPD, MS Thesis Defense, 2010
Geometry effect Porous membrane catheter NS, LPPD, MS Thesis Defense, 2010
Intensity-concentration relation • a. Through a sample of constant concentration • b. Through a sample of varying concentration NS, LPPD, MS Thesis Defense, 2010
Attenuation from a 3D spread NS, LPPD, MS Thesis Defense, 2010
Camera Capture effect and calibration Camera has a non-linear recording range. Calibration to find the attenuation coefficient. (Arbitrary units) NS, LPPD, MS Thesis Defense, 2010
Comparison of theoretical predictions and experimental values Results: Single port catheter experiments R2 = 0.98 R2 = 0.98, 0.97 NS, LPPD, MS Thesis Defense, 2010
Comparison of theoretical predictions and experimental values R2 = 0.98 R2 = 0.99, 0.97 NS, LPPD, MS Thesis Defense, 2010
Conclusions • Quantitative concentration measurement, instead of qualitative. • Less than 10% maximum measurement error. • Useful for verification of theoretical models that can be used for advanced computer simulations. • Can be applied for determining effective molecular diffusivity. NS, LPPD, MS Thesis Defense, 2010
M.S. Thesis Outline NS, LPPD, MS Thesis Defense, 2010
Motivation Morrison et al, 1999 NS, LPPD, MS Thesis Defense, 2010
Overview O. Ivanchenko, N. Sindhwani and A. Linninger, Experimental techniques for studying poroelasticity in brain phantom gels under high flow micro-infusion, Journal of Biomechanical engineering, May 2010. NS, LPPD, MS Thesis Defense, 2010
Stress Visualization NS, LPPD, MS Thesis Defense, 2010
Photoelasticity NS, LPPD, MS Thesis Defense, 2010
Stress visualization during infusion Isoclinic fringes Infusion late stages No infusion Infusion initial stages NS, LPPD, MS Thesis Defense, 2010
Displacement measurement NS, LPPD, MS Thesis Defense, 2010
Experimental setup NS, LPPD, MS Thesis Defense, 2010
Displacement field calculation. NS, LPPD, MS Thesis Defense, 2010
Displacement field and strains Porosity change NS, LPPD, MS Thesis Defense, 2010
Theoretical predictions Based on first principle conservation of mass and momentum Simulated strains (X, Y, volumetric), porosity changes, and hydroconductivity changes. NS, LPPD, MS Thesis Defense, 2010
Quantitative comparison of mathematical models and experimental results The profiles follow a similar trend, but agree poorly in terms of actual values. NS, LPPD, MS Thesis Defense, 2010
Conclusions • Stresses develop at the tip of infusion catheter • There is significant displacement of agarose gels. • Displacement magnitude decreases with distance from the catheter tip. • Displacement causes 50% increase in porosity. • These methods can be used for testing novel backflow free catheter designs. NS, LPPD, MS Thesis Defense, 2010
M.S. Thesis Outline NS, LPPD, MS Thesis Defense, 2010
Overview NS, LPPD, MS Thesis Defense, 2010
Computational models are based on First Principles of Mass and Momentum conservation Species transport: Clearance/ Binding Convection Reaction Diffusion Momentum: Extended Darcy’s Law Hydraulic Perfusion NS, LPPD, MS Thesis Defense, 2010
The Finite Volume Method NS, LPPD, MS Thesis Defense, 2010
Computational Results Brain Geometry Reconstruction Geometry Computer Algorithms Grid Generation Drug Distribution Prediction Extract geometry information MRI Data Computational Grid Model generation MR Imaging and geometry reconstruction using ImageJ NS, LPPD, MS Thesis Defense, 2010
Computer models of Nerve Growth Factor (NGF) delivery using CED: Isotropic domain NS, LPPD, MS Thesis Defense, 2010
Infusion in the caudate region of the brain, Axial slice simulation NS, LPPD, MS Thesis Defense, 2010
Infusion in the corpus callosum, Coronal slice simulation NS, LPPD, MS Thesis Defense, 2010
Infusion in the cingulum bundle, Sagittal slice simulation Ventricle NS, LPPD, MS Thesis Defense, 2010
Computer models of Nerve Growth Factor (NGF) delivery using CED: Anisotropic and heterogeneous domain NS, LPPD, MS Thesis Defense, 2010
Fibers of the Corpus Callosum Brain tissue is anisotropic and heterogeneous Lateral Ventricles • Internal structures • White matter fibers Caudate nucleus Putamen Corpus Callosum Globus Pallidus Third Ventricle Cortex Hippocampus NS, LPPD, MS Thesis Defense, 2010