Fits! Jason Richards, MD Resident, UNC Dept. of Neurology One year - PowerPoint PPT Presentation

Fits! Jason Richards, MD Resident, UNC Dept. of Neurology

One year ago... 11/12/2015 2

London, UK Chapel Hill, NC 11/12/2015 3

London, UK Chapel Hill, NC 11/12/2015 4

London, UK Chapel Hill, NC 11/12/2015 5

London, UK Chapel Hill, NC 11/12/2015 6

Intern House officer 7

Resident Registrar 8

Attending Consultant 9

Seizures Fits 10

http://shibleyrahman.com/dr-shibley-rahman-viewpoint/i-am-finally-discharged-from-queen-square/ 11

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Stephen McKay “Statue of Queen Charlotte in the Square's gardens” https://en.wikipedia.org/wiki/Queen_Square,_London#/media/File:Queen_Charlotte,_Queen_Square.jpg 13

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http://www.uclh.nhs.uk/OurServices/OurHospitals/NHNN/Pages/Home.aspx 15

http://www.julesthorntrust.org.uk/about_history.html 16

17 http://www.epilepsysociety.org.uk/epilepsy-society-research-centre#.Vjw_ItKrTuQ

18 https://en.wikipedia.org/wiki/William_Gowers_(neurologist)#/media/File:William_Richard_Gowers.jpg

https://en.wikipedia.org/wiki/Gowers%27_sign#/media/File:Gower%27s_Sign.png 19

While away I noticed many differences: 11/12/2015 20

While away I noticed many differences: Cultural 11/12/2015 21

While away I noticed many differences: Health systems Cultural 11/12/2015 22

While away I noticed many differences: Wada fMRI 11/12/2015 23

Overview • Epilepsy is one of the most common neurologic diseases » affects 0.5 - 1% of the population » 60% are focal epilepsies • 20% of patients with focal epilepsy are drug resistant » Defined as continued seizures despite two appropriate AEDs with good compliance 11/12/2015 Gelžinienė, Giedrė, et al. "Presurgical Evaluation of Epilepsy Patients." Medicina 24 (Kaunas) 44.8 (2008): 585-92. Web.

Overview • Chance of success decreases with successive drug trials » second AED response rate 14% » Third AED response rate 5% Gelžinienė, Giedrė, et al. "Presurgical Evaluation of Epilepsy Patients." Medicina 11/12/2015 25 (Kaunas) 44.8 (2008): 585-92. Web.

Epilepsy Surgery • One of first cases performed at Queen Square by Mr. Victor Horsley » Patient was a 22 year old with epilepsy from a car accident » Suffering prolonged episodes of “Jacksonian” status epilepticus » In 1866, operation removed the cortical scar » Once the wound healed, the seizures resolved Taylor, D. C. "One Hundred Years of Epilepsy Surgery: Sir Victor Horsley's Contribution." 11/12/2015 26 Journal of Neurology, Neurosurgery & Psychiatry 49.5 (1986): 485-88. Web.

Epilepsy Surgery https://en.wikipedia.org/wiki/Victor_Horsley 11/12/2015 27

Presurgical evaluation • Careful patient selection is key for good outcomes » Focal seizure onset should be established » Progressive lesions should be excluded » Resistance to medical therapy » Seizures interfering with daily life Gelžinienė, Giedrė, et al. "Presurgical Evaluation of Epilepsy Patients." Medicina (Kaunas) 11/12/2015 28 44.8 (2008): 585-92. Web.

Presurgical Evaluation • Optimal surgery lesions just enough tissue to eliminate seizures • Targeted area must not support essential functions, such as memory, motor or language » Testing is therefore need to precisely show the location of essential cortex Engel, Jerome, Jr,M.D., PhD. (1996). Surgery for seizures. The New England Journal of 11/12/2015 29 Medicine, 334 (10), 647-653.

Wada fMRI 11/12/2015 30

Wada testing • Test in which sodium amytal (barbiturate) is injected into the carotid arteries » Named for Juhn Wada, a Japanese psychiatrist » 30 patients hospitalized with psychiatric problems underwent the procedure » Each carotid artery was injected with sodium amytal, with the right being injected first » Patients became hemiparetic on the side contralateral to the injection. » Only one patient had a speech impediment with right sided injection. All had aphasia with left sided injection Wada, Juhn A. "Clinical Experimental Observations of Carotid Artery Injections of Sodium Amytal." Brain and Cognition : 11-13. Web. 7 Nov. 2015. 11/12/2015 31

Wada testing • Anesthesia typically lasts 4-8 minutes » Once hemiplegia is confirmed, language testing and memory tests are performed • Allows for localization of essential cortex Sharan, Ashwini, Yinn Cher Ooi, John Langfitt, and Michael R. Sperling. "Intracarotid Amobarbital Procedure for Epilepsy Surgery." Epilepsy & Behavior 11/12/2015 32 20.2 (2011): 209-13. Web.

Wada testing • Anesthetization is not always consistent due to variations in anatomy » Amount of flow to contralateral hemisphere can differ » Amount of posterior temporal lobe supplied by the anterior circulation is variable » Some patients have atresic anterior or posterior circulations Sharan, Ashwini, Yinn Cher Ooi, John Langfitt, and Michael R. Sperling. "Intracarotid Amobarbital Procedure for Epilepsy Surgery." Epilepsy & Behavior 11/12/2015 33 20.2 (2011): 209-13. Web.

Wada fMRI 11/12/2015 34

MRI Atomic nuclei have magnetic orientation and spin 11/12/2015 35 Berger, Abi. BMJ 324 (2002): 35.

MRI Atoms Atoms in magnetic field 11/12/2015 36 Berger, Abi. BMJ 324 (2002): 35.

MRI Atoms in magnetic field 11/12/2015 37 Berger, Abi. BMJ 324 (2002): 35.

MRI • Additional energy (in form of a radiowave) can deflect the magnetic vector and cause resonance • When radiowave is stopped, the magnetic vector relaxes • Time needed for magnetic vector to return to resting state is T1, • Time for spin relaxation is T2 Kim, Seong-Gi, and Seiji Ogawa. "Biophysical and Physiological Origins of Blood Oxygenation Level-dependent FMRI Signals." Journal of Cerebral Blood Flow & 11/12/2015 38 Metabolism J Cereb Blood Flow Metab 32.7 (2012): 1188-206. Web.

fMRI • Uses blood oxygenation level dependent (BOLD) contrast » Deoxyhemoglobin is an endogenous paramagnetic contrast agent » Changes in local deoxyhemoglobin concentration lead to alterations in MRI signal intensity • Coupling between neural activity and vascular dilation Kim, Seong-Gi, and Seiji Ogawa. "Biophysical and Physiological Origins of Blood Oxygenation Level-dependent FMRI Signals." Journal of Cerebral Blood Flow & 11/12/2015 39 Metabolism J Cereb Blood Flow Metab 32.7 (2012): 1188-206. Web.

fMRI • Glucose metabolism and cerebral blood flow are closely coupled • When upstream arterioles dilate, there is a decrease in the deoxyhemoglobin • This decrease is the basis of the fMRI image Kim, Seong-Gi, and Seiji Ogawa. "Biophysical and Physiological Origins of Blood Oxygenation Level-dependent FMRI Signals." Journal of Cerebral Blood Flow & 11/12/2015 40 Metabolism J Cereb Blood Flow Metab 32.7 (2012): 1188-206. Web.

fMRI • Due to different amounts of blood and brain in different areas, one cannot accurately compare signal between different voxels • Possible to compare a voxel to itself across tasks Kim, Seong-Gi, and Seiji Ogawa. "Biophysical and Physiological Origins of Blood Oxygenation Level-dependent FMRI Signals." Journal of Cerebral Blood Flow & 11/12/2015 41 Metabolism J Cereb Blood Flow Metab 32.7 (2012): 1188-206. Web.

fMRI orange = language task, green = right hand motor task Duncan, John S. "Imaging in the Surgical Treatment of Epilepsy." Nature Reviews Neurology Nat Rev Neurol 6.10 (2010): 537-50. Web. 11/12/2015 42

Language lateralization • Right handed people are generally left hemisphere language dominant • A 1999 study by Springer at al examined this issue using fMRI » Recruited 100 normal subjects and 50 subjects with epilepsy » All were right handed » Performed a tone decision and a semantic decision task Springer, J. A. "Language Dominance in Neurologically Normal and Epilepsy Subjects: A 11/12/2015 43 Functional MRI Study." Brain 122.11 (1999): 2033-046. Web.

Language lateralization Springer, J. A. "Language Dominance in Neurologically Normal and Epilepsy Subjects: A 11/12/2015 44 Functional MRI Study." Brain 122.11 (1999): 2033-046. Web.

Language lateralization • Study then generated a laterality index » Processed a mean of 7,899 voxels per subject » Threshold above which each voxel was considered “activated” » Volume of activated voxels on the left and rights sides was computed » Laterality index was generated (LV-RV)/TV » Numbers ranged from 100 (left dominant) to -100 (right dominant) Springer, J. A. "Language Dominance in Neurologically Normal and Epilepsy Subjects: A 11/12/2015 45 Functional MRI Study." Brain 122.11 (1999): 2033-046. Web.

Language lateralization Right dominant Mixed Left dominant Springer, J. A. "Language Dominance in Neurologically Normal and Epilepsy Subjects: A 11/12/2015 46 Functional MRI Study." Brain 122.11 (1999): 2033-046. Web.