Basis of the Brain and Cranial Nerves

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Unit 11: Basis of the brain and cranial nerves Chapters 7 and 9 (Head and cranial nerves) and lecture/seminar material GENERAL OBJECTIVES: - Understand the organization of the brainstem. - Understand how the ‘inner structures’ (nuclei, tracts, ventricles) affect the surface of the brainstem. - Distinguish, basis of the brainstem, tegmentum and tectum. - Understand the principle of the organization of cranial nerve nuclei. SPECIFIC OBJECTIVES: Medulla -Describe principle features on ventral and dorsal views of medulla -Describe features of the rhomboid fossa (anterior wall of the fourth ventricle) -Describe how ‘opening’ of the ventricular system in fourth ventricle affect distribution of motor and sensory nuclei distributed in tegmentum of medulla and pons -Which cranial nerves leave anterior/lateral aspect of medulla and in which order? Pons -Describe principle features on ventral and dorsal views of the pons -Which cranial nerves leave the brainstem on the ventral border between pons and medulla and in which order? -Describe how cerebellum connects to the brainstem segments. -What is facial colliculus and where is it located? Mesencephalon -Describe principle features on ventral and dorsal aspects of mesencephalon -What are cerebral crura and what is interpeduncular fossa? -What are superior and inferior colliculi? -Which cranial nerves leave ventral and dorsal aspects of mesencephalon? Cranial nerves Describe location of cranial nerve nuclei according to the segment of the brainstem (pons, medulla, mesencephalon) and their nature (in relation to sulcus limintans): Motor: somatic, branchial and visceral Sensory: visceral, special and general For each and every cranial nerve name the nature of fibers they contain, how they leave the surface of the brainstem and how they leave cranial cavity. .

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Role of Endoscopy in Management of Hydrocephalus
8 Role of Endoscopy in Management of Hydrocephalus Nasser M. F. El-Ghandour Department of Neurosurgery, Faculty of Medicine, Cairo University Egypt 1. Introduction Management of hydrocephalus is the most beneficial indication for endoscopy. To cure hydrocephalus and thereby render an individual shunt independent is a great achievement. The standard and the most commonly performed endoscopic procedure is endoscopic third ventriculostomy. However, the field of neuroendoscopy is prepared to extend itself beyond just the ventriculostomy procedure. The neuroendoscope plays other important roles in the management of hydrocephalus. Although the literature is focusing mainly on the role of endoscopic third ventriculostomy in the treatment of aqueduct stenosis, the indications for endocopy continues to increase rapidly. With increasing experience, and improved endoscopic instruments, another important role of endoscopy has been emerged in approaching intraventricular tumors which may be completely removed without microsurgical brain dissection (Gaab & Schroeder, 1998). In addition to tumor removal it is usually possible to restore obstructed cerebrospinal fluid pathways using the same approach by performing ventriculostomies, septostomies or stent implantation (Oka et al., 1994). The goal of this chapter is to present the role of endoscopy in the management of hydrocephalus. The following chapter gives a comprehensive review about the indications, outcome, complications, and advantages of endoscopy. Various procedures which can be performed endoscopically for the management of hydrocephalus will be discussed. 2. Historical perspectives Endoscopy was introduced in the neurosurgical speciality at the beginning of this century. In 1910, L’Espinasse used the cystoscope to perform the first registered endoscopic procedure. He explored the lateral ventricle and coagulated the choroid plexus in 2 infants with hydrocephalus (Walker, 2001).
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