Category Archives: Neurological Diseases and Diseases of Voluntary Muscle

THE TRIGEMINAL NERVE (FIFTH CRANIAL NERVE)

The trigeminal nerve is mainly sensory but contains some motor fibres. Sensory fibres from the three divisions-ophthalmic (VI)’ maxillary (V2) and mandibular (V,) – pass to the trigeminal ganglion at the apex of the petro us temporal bone. From here central fibres enter the brain stem. Ascending fibres transmitting the sensation of light touch enter the nucleus in the pons. Descending fibres carry

The pupils

Sympathetic impulses from fibres in the nasociliary nerve stimulate the dilator muscle of the pupil (dilator pupillae). Preganglionic sympathetic fibres to the eye (and face) {yiginate in the hypothalamus, pass uncrossed through re midbrain and lateral medulla and emerge finally from the spinal cord at Tl (close to the lung apex). Postganglionic fibres begin in the superior cervical ganglion. These pass to t

The cranial nerves

THE OLFACTORY NERVE (FIRST CRANIAL NERVE) This sensory nerve arises from olfactory (smell) receptors in the nasal mucosa. Branches pierce the cribriform plate and synapse in the olfactory bulb. The olfactory tract then passes to the olfactory cortex in the anteromedial surface of the temporal lobe. Loss of the sense of smell (anosmia) occurs with head injury andtumours of the olfactory groove (e.g. meningioma

The Cerebral Cortex

CEREBRAL LOCALIZATION This subject causes everyone considerable difficulty. The following paragraphs summarize the areas of principal clinical importance in general medicine . The dominant hemisphere The concept of cerebral dominance arose with the observation that right-handed stroke (and other) patients with acquired language disorders had destructive lesions within the left hemisphere. Almost all right-hand

Functional Anatomy

The functional unit of the nervous system is the neurone, with its cell body and axon, which terminates at a synapse. The specificity, size and type of each group of neurones varies greatly. For example, an ex motor neurone of the anterior horn cell of the lumbar spinal cord has an axonal length of over 1 m and innervates several hundred to 2000 muscle fibres-to form the motor unit. By contrast, a spinal or

Investigation

The history and examination remain most valuable ‘tests’ in neurology, but computed tomography (CT), magnetic resonance imaging (MRI), and other non-invasive tests have revolutionized the management of patients. Grades of muscle weakness (Medical ResearchCouncil). look at the patient: General demeanour Speech Gait Arm swinging Examine head: Fundi Pupils Eye movements Facial movements Tongue Examine u

Neurological examination

The following headings summarize the essential elements of the clinical examination: 1 State of consciousness, arousal 2 Appearance, attitude, insight 3 Mental state 4 Orientation in time and place 5 Recall of recent and distant events/memory 6 Level of intellect 7 Language and speech/cerebral dominance 8 Disorders of higher function (e.g. apraxia) 9 Gait 10 Romberg’s test 11 The skull-shape, circumference,

Symptoms

There are two essential questions in any neurological diagnosis: 1 What is/are the site(s) of the lesion(s)? 2 What is the likely pathology? Most of the diagnoses in neurology are made on a detailed history alone. The method of recording the details is beyond the scope of this chapter, but an important point is that the history should read chronologically and portray the story of the disease. A summary should

Neurological Diseases and Diseases of Voluntary Muscle

Introduction The wide range of neurological conditions seen in the UK is summarized in Table 18.1. The pattern of practice has changed much in the last 40 years with the disappearance of poliomyelitis, and (almost) of neurosyphilis, the treatment for Parkinson’s disease, the use of newer anticonvulsants and now, the emergence of AIDS. Despite clinical neurology being primarily concerned with the organic