1. Polymicrogyria Natalie Crawford Karen Inzana D. Phillip Sponenberg Virginia – Maryland Regional College of Veterinary Medicine Blacksburg, Virginia Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

2. Polymicrogyria (also known as microgyria)  Malformation of the cerebral cortex  Neuronal migration defect leading to abnormal lamination  Excessive production of gyri  Associated with other brain malformations Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

3. Veterinary Medicine  Ruminants Cattle Sheep  Rats Experimentally induced  Dogs Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

4. Historical Perspective  Van Winkle et. al. (1994) Four related Standard Poodle dogs with cortical blindness Young dogs (5-9 months)  Jurney et. al. (2008) Four un-related Standard Poodle dogs with cortical blindness and behavioral abnormalities Three young dogs (3-4 months) One older dog (5 years) Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

5. Allegro  3 month old male intact Standard Poodle  Decreased vision Noticed from 9 weeks of age  Abnormal behavior  Possible decreased hearing Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

6. Diagnosis  Ophthalmic Examination No ophthalmic cause for blindness  Neurologic Examination Generalized or diffuse encephalopathy Cortical blindness Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

7. Other Findings Gross lesions - Definitive Histologic lesions Imaging (MRI) Not done in Allegro’s case Brain Activity Monitoring (EEG) Not done in Allegro’s case Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

8. Gross Findings Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

9. Histologic Lesions Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

11. Normal Nissl Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

12. H&E (07-1996.4) Polymicrogyria H & E Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

13. Polymicrogyria Nissl Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

15. Polymicrogyria Phenotype  Clinical Presentation Standard Poodles 0-6 months of age Cortical Blindness Gross lesions  Outcome Euthanasia Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

16. Human Medicine  Frequent occurrence  Manifests with varying degrees of mental retardation, developmental delays and seizure activity Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

17. Schulyer Hudson  Bilateral Persylvian Polymicrogyria Partial paralysis of muscles of the face, jaws and throat Learning difficulties Cerebral palsy Seizures  Genetic www.darn-tootin.com Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

18. Literature  Veterinary Neuropathology, Summers B, et al. (1995)  Blindness Due to Polymicrogyria and Asymmetrical Dilation of the Lateral Ventricles in Standard Poodles, Van Winkle TJ, et al. (1994)  Neuropathology: A Reference Text of CNS Pathology, 2 nd Ed., Ellison D, et al. (2004) Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

19. Acknowledgements  D. Phillip Sponenberg  Karen Inzana  Carrie Jurney Jurney C, et al. Polymicrogyria in Four Standard Poodles: A Case Series with Histopathologic, Electroencephalographic and Magnetic Resonance Imaging Findings. Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

20. Contributors  Jamie Haddad – UPenn  Thomas Van Winkle – UPenn  Andrew Miller – Cornell  Andras Komaromy – UPenn  Charles Vite - UPenn  Gayle Johnson - Missouri  Dennis O’Brien – Missouri Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

21. Questions? Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only