Meningioma – spinal

Etiology Meningiomas are tumors that arise from the thin membranous layer surrounding the central nervous system called the meninges. Specifically meningiomas arise from the arachnoid "cap" cells of the arachnoid villi in the meninges. Meningiomas tend... Read More

Occipital Dysplasia

Etiology Occipital dysplasia is a congenital abnormality of the formation of the occipital bones of the cranium. The most common manifestation of this condition is an underdeveloped occipital bone leading to a dorsoventrally enlarged ("keyhole shaped") foramen... Read More

Caudal Occipital Malformation Syndrome – COMS

Etiology Phenotypic selection has led to variability in canine skull shape. The brachycephalic phenotype was selected initially for its strong bite force. Later, breeds with round heads and foreshortened noses were desired because their facial... Read More

Brain Infarction – Nonhemorrhagic

Etiology Nonhemorrhagic infarctions, otherwise called ischemic infarctions, are the result of the acute interruption of blood flow to an area within the brain. The usual cause for a nonhemorrhagic infarction is the occlusion of an... Read More

Brain Infarction – Hemorrhagic

Etiology Hemorrhagic infarctions (otherwise known as intracerebral hemorrhage or cerebral bleed) are the result of spontaneous hemorrhage within the brain. Underlying conditions that predispose to hemorrhagic infarctions include hypertension, aneurysms and brain tumors. Hemorrhagic infarctions differ from nonhemorrhagic infarctions (otherwise called ischemic … Read More

Ectopic Ureter

Etiology Ectopic ureters are a congenital condition that occur when the embryonic mesonephric and metanephric duct systems do not develop normally. The metanephric duct eventually develops into the ureter. In patients with ectopic ureters, the metanephric duct originates in an abnormal location or migrates in … Read More


Etiology Hydranencephaly is a congenital malformation of the brain in which the cerebral hemisphere(s) are absent to varying degrees. Hydranencephaly is an extreme form of porencephaly, a condition in which large cystic regions develop within the cerebral hemispheres.  Pathophysiology The abnormal … Read More