Speakers

Glioneuronal tumors in children
1109 16:00-16:10
AASNS & WANS Joint Seminar/305
Glioneuronal tumors represent a rather rare and distinct group of brain tumors, most commonly seen in children and young adults. Although histopathologically variable, they share the common features having neoplastic ganglion cells with glial elements and regarded as low-grade tumors. Majority have a favorable prognosis and can be cured by surgical excision without requiring radiation or chemotherapy. Clinical presentation is either seizures due to focal irritation or ventricular obstruction rather than infiltration of the neuronal circuits. Nevertheless, there has been cases which fall outside the expected trail showing aggressive behavior computable to high grade tumors. Unexpected behavior of any brain tumor is attributed to specific molecular alterations within the tumor cells otherwise sharing same morphological properties. This has created major paradigm shift in classification of brain tumors during the last two decades many entities are now defined by means of specific molecular alterations. Molecular data of the tumors with the different outcomes is more often used to tailor the integrated treatments based on molecular pathogenesis. Unfortunately, molecular properties did not provide useful data on glioneuronal tumors that would differentiate aggressive behavior in those with similar histopathological properties. This presentation is intended to describe the patterns of aggressive behavior on 51 cases of various glioneuronal tumors in terms of clinical presentation, radiological and histopathological properties and discuss how much testing should be done in an individual glioneuronal tumor to appreciate a diverse outcome.

Hemispherotomy for resistant epilepsy
1110 08:30-08:40
Functional Neurosurgery & Epilepsy/304A
Drug-resistant epilepsy due to hemispheric syndromes due to prenatal vascular events affecting one hemisphere unilaterally, Sturge-Weber, hemimegalencephaly, diffuse cortical dysplasia, Rasmussen encephalitis or post-traumatic injuries has dismal prognosis. A significant portion of these pathologies constitute an important group of lesional epilepsies, especially in numerous drug-resistant epilepsies that occur in infancy and early childhood, and catastrophic epilepsy syndromes. Considering the damage that epilepsy causes to mental and psychomotor development in this patient group with uncontrolled seizures that tend to occur at a very early age and become very frequent, the chance of surgery should be investigated without delay with different drug combinations. When applied with appropriate indications and techniques, one of the surgical methods that provides the best seizure control is the disconnection of one hemisphere from the rest of the central nervous system. This concept, has undergone many modifications since it was first published as anatomic hemispherectomy by Mc Kenzie in 1938. Regardless of the method used, the two most important indications for the separation of a hemisphere from the system are dysfunction of one hemisphere and the presence of seizures originating from the same hemisphere. Resective techniques In addition to perioperative morbidity, have the risk of late-onset hydrocephalus and, although rarely, hemosiderosis. Perinsular approaches called hemispherotomy, which are based on the principle of disconnecting the hemisphere without performing large excisions, have become more frequently used after the 1980s. Nevertheless, certain pathologies may still require anatomic resections and techniques of anatomic, functional and disconnective procedures for disconnection will be discussed in this presentation