NEUROSURGERY SIGNS OF NEUROSURGICAL DISEASE RAISED INTRACRANIAL PRESSURE MENINGEAL IRRITATION BRAIN TUMOURS HEAD INJURY

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1 11 NEUROSURGERY SIGNS OF NEUROSURGICAL DISEASE RAISED INTRACRANIAL PRESSURE MENINGEAL IRRITATION BRAIN TUMOURS HEAD INJURY

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3 NEUROSURGERY SIGNS OF NEUROSURGICAL DISEASE FOCAL NEUROLOGY Frontal /parietal regions speech plus motor function on dominant side Parietal/occipital regions sensory plus spatial orientation Occipital visual field Temporal speech(dominant side) plus visual, epilepsy Cerebellum coordination/balance Cranial nerves I XII RAISED INTRACRANIAL PRESSURE (ICP) Normal <200 mmh 2 O Increased volume of CSF Obstruction of normal flow in ventricles, obstructive hydrocephalus Obstruction of normal flow in subarach space communicating hydrocephalus Excessive CSF production papilloma of choroid plexus Increased cranial contents Space-occupying lesion Tumour Abscess Cyst Haematoma Increased volume of intracranial blood Venous obstruction of intracranial sinuses Vasodilatation in hypercapnia Decreased skull size craniosynostosis CLINICAL FEATURES OF RAISED ICP Headache, especially in the morning Vomiting Drowsiness Papilloedema plus retinal haemorrhages Fontanelle bulging in children LATE SIGNS DUE TO DISTORTION OF BRAIN SHAPE Tentorial notch pressure Ipsilateral IIIrd nerve dilated pupil Pyramidal tract motor weakness Posterior cerebral art occipital lobe infarction> permanent homonymous hemianopia Downward pressure on brainstem Bilatera VIth nerve Cerebellar tonsillar herniation Neck stiffness Bradycardia, hypertension (Cushing response) Respiratory arrest 243

4 SURGERY: FACTS AND FIGURES MENINGEAL IRRITATION Features Headache Neck stiffness Nausea, vomiting Photophobia Causes (cf. peritonitis) Blood subarachnoid haemorrhage Pus Spontaneous Post-head injury (especially damage to paranasal sinuses), pneumococcal meningitis Dermoid fistula (midline lesion over vertex of skull) Malignant cells primary or secondary Chemical Post-LP Cholesterol meningitis leakage of cholesterol via dermoid, epidermoid cyst or craniopharyngioma Investigations Skull XR CT scan MRI/MRA scans Angiography Lumbar puncture BRAIN TUMOURS PRIMARY OR SECONDARY Overall incidence 5/100,000 Neuroepithelial 50% Metastatic 15% Menigioma 15% Pituitary 8% Risk factors Non-firm genetic or environmental link established Increased incidence of tumours in: Neurofibromatosis glioma, meningioma, acoustic neuroma Tuberous sclerosis astrocytoma Von Hippel Lindau haemangioblastoma Extracerebral Meninges meningiomas, pressure symptoms, good prognosis Nerves neuroma (especially acoustic neuroma), tinnitus, vertigo, facial pain Vascular haemangioblastoma (2%), cerebellum, highly vascular 244

5 NEUROSURGERY Pituitary anterior, adenoma Optic chiasm compression, bitemporal hemianopia Pituitary function decreased, hypothyroid, adrenal, gonad Secreting prolacatin, corticotrophin or growth hormone Bone chordoma <1%, embryo notochord remnant Intracerebral Gliomas grade 1 4 depending on histology, rapid presentation, poor prognosis grade 4 (glioblastoma multiforme) Astrocytoma Oligodendroglioma Ependymoma Medulloblastoma Lymphoma Pineal gland tumour <1% Parinaud syndrome(upward gaze ocular convergence paralyses) Germinoma (80 90%), choricarcinoma, endodermal sinus tumour Raised AFP, HCG Papilloma of choroid plexus Metastases NON-MALIGNANT SPACE-OCCUPYING LESIONS Abscess Congenital cysts Parasitic cysts Granuloma, e.g. TB Vascular anomalies Management principles Establish diagnosis Treat raised ICP Anti-convulsant therapy Preoperative devascularization of tumours, e.g. large meningioma via embolization Surgical tumour biopsy /removal Stereotactic Craniotomy Adjuvant treatment radiotherapy METASTATIC TUMOURS Present in 30% of patients with systemic cancer Lesions in distal arterial fields, especially mid cerebral articulation Multiple Approximate primary origin Lung 40% Melanoma 11% Kidney 11% Colon 8% 245

6 SURGERY: FACTS AND FIGURES CEREBRAL ABSCESS 75% local spread of infection frontal sinus/middle ear 25% systemic spread, congenital heart lesion Treat with Burr hole aspiration Antibiotics Other management as for tumour HEAD INJURY Blunt Penetrating Cause of trauma, e.g. collapse, post-epilepsy Most common cause of death in children High morbidity post-major head injury Damage to: Brain acceleration deceleration Diffuse brain injury Mild = concussion Severe = dementia, spasticity Pathological neuronal damage due to rotatory shear forces Local brain injury Contracoup damage Localized intracerebral/subarachnoid bleeding and oedema Skull fractures Linear Basal Compound Depressed Complications of head injury Intracranial bleed extradural/subdural/subarachnoid/intracerebral Cerebral ischaemia Respiratory failure Circulatory failure Cranial nerve damage II, III, V VIII CSF rhinhorea CSF otorrhoea Brain abscess Meningitis Epilepsy Diabetes insipidus Traumatic fat embolism (in major trauma) Carotico-cavernous fistula (rare) 246

7 NEUROSURGERY Basic management of head injuries Trauma protocol A Airway assessment intubate and ventilate in unable to maintain own airway B/C Breathing/ventilation respiratory rate, pulse, BP, O 2 saturation and resuscitate as appropriate D Disability conscious level (GCS), pupil size and reaction, peripheral neurology E Exposure/environmental control head, scalp, ear and nose examination Further assessment Need to exclude intracranial bleed or serious brain injury CT scan indications Skull fracture plus decreasing GCS/confusion/focal neurology/seizures Persistent confusion/decreased GCS Deteriorating conscious level Depressed skull fracture Penetrating/open skull fracture with CSF Leak Difficult assessment, e.g. alcohol Skull X-ray indications Loss of consciousness/amnesia Suspected fracture CSF leak Admission and observation indications Confused, decreased conscious level but stable Persistent headache, nausea, vomiting Difficult assessment Poor social support. INTRACRANIAL BLEEDS Extradural Damage to middle meningeal artery or large venous sinus Usually present within 24 h post-injury, occurs after lucid interval History of trauma Swelling +/ skull fracture over site Deteriorating conscious level late signs ipsilateral pupil dilation, contralateral motor weakness Need craniotomy and clot evacuation Subdural Acute post-trauma to frontal/temporal lobes, assigned with brain swelling, damage to bridging veins Chronic infantile <6 months or elderly >60 years of age, cerebral atrophy, coagulopathy Decreased conscious level Meningeal irritation Need craniotomy and clot evacuation 247

8 SURGERY: FACTS AND FIGURES Figure 11.1 Axial CT showing a large right temporal extradural haematoma. The fresh blood is highly dense (white). From: Sports Medicine: Problems and Practical Management (Eds. E. Sherry & D. Bokor); Greenwich Medical Media, 1997: page 81. Figure 11.2 Axial CT of a subdural haematoma with midline shift. Note the haematoma is characteristically more extensive and crescenteric in shape. From: Sports Medicine: Problems and Practical Management (Eds. E. Sherry & D. Bokor); Greenwich Medical Media, 1997: page 81. Subarachnoid Post-traumatic severe head injury Spontaneous Rupture of saccular intracranial aneurysm Present in 3% of individuals, circle of Willis Sudden onset headache Meningism Deteriorating conscious level Focal neurological signs Complications 248

9 NEUROSURGERY Death in massive bleed Irreversible cerebral ischaemic damage Rebleed 4% in 24 h; 19% in 2 weeks Cerebrovascular vasospasm Hydrocephalus Electrolyte disturbance Cardiac arrhythmia Diagnosis History Examination CT presence of blood in subarachnoid space LP xanthochromia Anterior communicating (28%) Terminal carotid (8%) Middle cerebral (27%) Basilar (3%) Posterior communicating (30%) Superior cerebellar (1%) Posterior inferior cerebellar (1%) Figure 11.3 Anatomical distribution of cerebral aneurysms (figures denote percentage of total). MRA Angiography identify possible site of lesion Treatment Medical Resuscitation intubate and ventilate if required Anti-hypertensives nimodipine, decreases risk of neurological deficit and death Anti-convulsants phenytoin Raised ICP steroids 249

10 SURGERY: FACTS AND FIGURES 13 cm 3 cm 4 cm 8 cm 4 cm 4 cm 3 cm Figure 11.4 Sites of burr holes. Hypervolaemic haemodilution > reduces vasospasm and cerebral ischaemia Surgical Venticulostomy in progressive hydrocephalus Lesion identifies and ablated via craniotomy and clipping Alternative technique; endovascular occlusion CEREBRAL ANEURYSM Incidental findings >10 mm high risk of rupture = elective treatment advised <5 mm, or difficult to approach surgically monitor wct scans Infectious aneurysm Subacute endocarditis Antibiotics and monitoring 250