Gökhan Kurt

By Mehmet Tönge and Gökhan Kurt

Part of the book: Advances in the Biology, Imaging and Therapies for Glioblastoma

By Gökhan Kurt and Ayfer Aslan

Craniopharyngioma (CP) is a rare, benign, slow-growing, but clinically aggressive tumor located mainly in the sellar and suprasellar regions. While it occurs equally in children and adults, there are two peaks in the age distribution: first in 5–14 years of age and second in 45–74 years of age. The clinical presentation varies according to the age of patients, while the predominant symptoms are visual disturbances, headache, and endocrine dysfunctions. CPs are topographically classified in several subgroups based on the relationship of the tumor to the sella, diaphragma sellae, optic chiasm, stalk, and third ventricle; whereas the pathological classification includes two types: adamantinomatous (aCP) and papillary (pCP). Distinctive features of aCP are cysts with content of “motor-oil” fluid, calcification, wet keratin, peripheral palisading of basal cells, stellate reticulum, and mutations in CTNNB1/β-catenin gene; and those of Pcp are regular stratified squamous epithelium, devoid of cilia, papillary projections, no calcification, rare cyst with a clear fluid, and mutations in BRAF V600E. The surgical approaches include transcranial (subfrontal, pterional, transcallosal, and transcortical-transventricular) and transsfenoidal approaches, having different selection criteria, advantages, and disadvantages. Despite complete resection and radiotherapy, CPs are inclined to recur causing high morbidity and mortality.

Part of the book: Central Nervous System Tumors

By Mustafa Caglar Sahin and Gokhan Kurt

Pituitary neuroendocrine tumors (PitNETs) arising from adenohypophyseal cells are generally accepted as benign. It is a very heterogeneous group of tumors according to their origin, biological behavior, and growth patterns. It is the third most common intracranial tumor type after meningiomas and gliomas. Transsphenoidal surgery (TSS) is the primary treatment of choice in all PitNETs except for lactotroph tumors, which are primarily treated with dopamine agonists. In this book section, surgical approaches in the treatment of PitNETs will be explained. In addition, PitNET radiosurgery will be explained in detail by using current literature information.

Part of the book: Central Nervous System Tumors

By Zeynep Balaban and Gokhan Kurt

Autonomic nervous system (ANS) regulates the physiologic process in the body and has essential role in the systems such as blood pressure regulation, respiration, heart rate, and sexual arousal. ANS is divided into the sympathetic nervous system and the parasympathetic nervous system and regulates whole organism functions in the body. Although the main neurotransmitters in the ANS are norephinephrine, epinephrine, and acetilcholine, many other different agents and chemicals play an important role of the neurotransmitters function. These molecules act on many different receptors and sides. This chapter provides a detailed evaluation of neurotransmitters, related molecules, their receptors and how they function to maintain autonomic functions in both the central and peripheral parts of the systems.

Part of the book: Topics in Autonomic Nervous System