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Clinical Features :Intracranial tumors produce three kinds of symptoms: a) General symptoms - related to intracranial pressure (ICP) - Headache: brain itself is not pain sensitive, tumour headache arise from stretching of dura-matter and intracranial vessels.- Nausea & vomiting.- Seizures.b) False localizing signs- sixth cranial nerve palsy, headache. It does not depend only on site of lesion, but on other factors like rapidity of growth of tumour, duration of disease. c) Local symptoms- specific to the tumour's location. 1) Frontal lobe syndrome: · Anterior frontal tumours : changes in personality, loss of initiative, and abulia.· Posterior frontal lobe tumours: contra-lateral weakness, with expressive aphasia.· Bifrontal disease :impairment of memory, lability of mood, urinary incontinence, and frank dementia.2) Temporal lobe syndromes: severe memory impairment, homonymous superior quadrantanopsia, auditory hallucinations, abnormal behavior and fluent (Wernicke's-like) aphasia. 3) Parietal lobe tumours: affect sensory and perceptual functions more than motor modalities. Stereoagnosis, hemianesthesia, poor proprioception, homonymous inferior quadrantanopsia, · Non-dominant parietal lobe tumors: contralateral neglect, anosognosia and apraxia for self-dressing.· Dominant parietal lobe tumors : alexia, dysgraphia, and apraxia.4) Occipital lobe tumours: contra-lateral homonymous hemianopsia; complex visual aberrations affecting perception of color, object size, or location. · Bilateral occipital disease - cortical blindness.5) Classic corpus callosum disconnection syndromes :rare disorder · Interruption of the anterior part of the corpus callosum- failure of the left hand to carry out spoken commands.· Lesions in the posterior corpus callosum - inability to read or name colours.6) Thalamic tumours:both local effects and obstructive hydrocephalus. · Basal ganglia involvement: "Thalamic" pain disorders or motor syndromes.7) Brainstem disease : · ‘Long tract sign, cranial nerve palsies, ataxia with less than 2 month disease duration’.· Pontine astrocytoma (glioma)- cranial nerve VI and VII palsies. Also, hemiplegia, unilateral limb ataxia, ataxia of gait, paraplegia, hemisensory syndromes, gaze disorders, and hiccups.· Midbrain-Tectal involvement : Parinaud's syndrome, Peduncular lesions: contralateral motor impairment,obstruction of the aqueduct causes hydrocephalus. · Medulla - fulminant course with cranial nerve palsy of VII, IX, and X. dysphagia, dysarthria, respiratory distress.8) Cerebellar tumours : localizing presentations. · Midline lesions- truncal and gait ataxia,· Lateral hemispheric lesions : unilateral appendicular ataxia,abnormal head position, bilateral VI cranial nerve palsiesCerebral Herniation -Herniation syndromes with respiratory arrest and death or paraplegia or quadriplegia. Types: 1) Subfalcine, 2) Transtentorial, 3) Tonsillar. § Subfalcine herniation - from a unilateral frontal tumour, is often asymptomatic.§ Transtentorial (temporal lobe) herniation - compressing cranial nerve III and the ipsilateral cerebral peduncle. Coma usually follows.§ Tonsillar herniation - increasing posterior fossa mass effect displaces one or both cerebellar tonsils into the foramen magnum, causing posturing, coma, and respiratory arrest.
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Brain Tumour Foundation Of India Tata Memorial Hospital,
Ernest Borges Marg, Parel, Mumbai - 400 012, INDIA
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