INVESTIGATIO NS NEUROSURGICAL INVESTIGATIONS A Cerebrospinal fluid

INVESTIGATIO NS

NEUROSURGICAL INVESTIGATIONS A. Cerebrospinal fluid examination CSF B. imaging study • Plain X-rays • CT scan • MRI • Cranial and Spinal Angiography. • Myelography • Positron emision tomography • MR spectroscopy • MR tractography C. Electroencephalography (EEG). D. Nerve conduction Studies/Electromyography (EMG). E. Nerve and muscle biopsy F. Hormonal tests

CEREBROSPINAL FLUID(CSF) INVESTIGATION It can be obtained by 1. 2. Spinal : lumber puncture LP Cranial : lateral ventricular puncture fluid can be accessed most safely in the lumbar cistern, where the spinal cord has terminated into the cauda equina (between the level of the first and second lumbar vertebrae. The lumbar cistern extends into the sacrum.

LUMBAR PUNCTURE

LUMBAR PUNCTURE

LUMBAR PUNCTURE INDICATIONS 1. 2. 3. 4. 5. 6. 7. suspected meningitis subarachnoid hemorrhage SAH cytology in neoplastic diseases measurement of intracranial pressure ICP therapeutic CSF aspiration (benign raised intracranial pressure)(pseudotumor cerebri). conventional myelography by contrast injection Spinal anesthesia

MEASUREMENT OF INTRACRANIAL PRESSURE

CONTRAINDICATIONS TO LUMBAR PUNCTURE 1. raised intracranial pressure other than pseudotumor cerebri. Features suggestive of raised ICP are 1. 2. 3. 4. 5. focal neurological deficit recent seizure papilloedema. Sepsis at the site of LP Bleeding tendency like coagulopathy and thrombocytopenia less than 50 × 109 /L Abnormal respiration i. e. moribund patient Vertebral deformities ( kyphosis and scoliosis )

COMPLICATIONS OF LUMBAR PUNCTURE 1. 2. 3. 4. 5. 6. 7. Post spinal headache triad treatment Cerebellar tonsillar herniation if there is raised ICP. Injury to the neural structure Back pain infection and meningitis Implantation of cutaneous tissue with subsequent epidermoid cyst Bleeding

IMAGING INVESTIGATIONS • Plain X-rays • CT scan • MRI • Angiography. • Myelography • Positron emmision tomography • MR spectroscopy • MR tractography

PLAIN X-RAY A. Skull X-ray: AP and lateral view B. Plain X-rays of the spine: a. X-rays of cervical spines b. X-ray of thoracic (dorsal) spines c. X-ray of the lumbosacral spines

The major abnormalities to look for on a skull X-ray are: 1. Fractures linear and depressed 2. Hyperostosis, e. g. meningioma. 3. Bone erosion due to skull vault tumours. 4. 5. Abnormal calcification, e. g. tumours such as meningioma, oligodendroglioma, craniopharyngioma or calcified wall of an aneurysm. Signs of long-standing raised intracranial pressure v erosion of the dorsum sellae v Double floor sella torcica v copper beating appearance of the skull vault.

PLAIN X-RAYS OF THE SPINE Particular 1. 2. 3. 4. 5. note should be taken of: Vertebral alignment. Presence of degenerative disease with narrowing of the neural foramina and spinal canal. Evidence of metastatic tumour with erosion or sclerosis of the vertebral body, pedicles or lamina. Enlargement of a neural foramen indicating a spinal schwannoma. Congenital abnormalities such as spina bifida.

COMPUTED TOMOGRAPHY (CT)SCAN Indications for Computed Tomography in Neurosurgery: A. 1. Cranial CT: Diagnosis of acute neurosurgical lesions in the head and spine, including: Skull and spinal fractures. b. Intracranial hemorrhage: like extradural haematoma, subdural haematoma, intracerebral haematoma. 2. Oedema: brain oedema whether due to trauma or other cause. 3. Mass lesions: mainly brain mass lesions like tumours and brain abscess. 4. Hydrocephalus 5. Stroke: differentiate between infarction and intracranial haemorrhage.

INDICATIONS FOR MAGNETIC RESONANCE IMAGING 1. Intracranial tumous. 2. cerebral abscess. 3. Arteriovenous malformations. 4. Venous sinus thrombosis. 5. Craniospinal abnormalities such as the Chiari malformation. 6. Syringomyelia. 7. Spinal tumours. 8. Disc prolapse (including cervical, lumbar and dorsal disc prolapse). 9. Spinal canal stenosis (lumbar or cervical stenosis) and cervical myelopathy.

$CT IS BETTER THAN MRI Diagnoses of bone related pathologies like fractures and bone$

CT IS BETTER THAN MRI Diagnoses of bone related pathologies like fractures and bone tumors. Better for acute hemorhagic lesions Less time is needed to perform CT than MRI (few minutes) critically ill patients.

MRI IS BETTER THAN CT 1. Sellar pathology (pituitary) 2. Posterior fossa tumours (cerebellar and brain stem tumours). 3. Spinal cord pathology (compression and tumours), and one can do myelography with non invasive method (no need for lumbar puncture). 4. Infarction can be diagnosed as early as few hours whereas CT needs 48 hours to diagnose it. 5. No ionizing radiation. Can be repeated safely

CT VERSUS MRI

CONTRAINDICATIONS TO MRI 1. Metallic foreign bodies anywhere in the body like plating and screwing, shells , cardiac pace maker, intracranial clips 2. Claustrophobia. 3. Gross obesity 4. Uncontrolled movement disorders (Parkinson’s disease). 5. Respiratory disease that require assisted ventilation or carry risk of apnea

CRANIAL AND SPINAL ANGIOGRAPHY images of blood vessels … arteriovenous malformations and aneurysms

ELECTROENCEPHALOGRAPHY(EEG) Ø Diagnosis and follow up of epileptic patients with seizure focus localization Ø sleep disorders, coma, encephalopathies. Ø To differentiate epileptic seizures from other types of spells, such as psychogenic non-epileptic seizures Ø to characterize seizures for the purposes of treatment

ELECTROENCEPHALOGRAPHY( EEG)

NERVE CONDUCTION STUDIES/ ELECTROMYOGRAPHY(EMG) Carpal tunnel syndrome Guillain-Barré syndrome Peripheral neuropathy Spinal disc herniation

NERVE CONDUCTION STUDIES/ ELECTROMYOGRAPHY(EMG)

POSITRON EMISSION TOMOGRAPHY PET A positron emission tomography (PET) scan is an imaging test that can map tissue biochemistry and physiology i. e functional test The most commonly used PET tracer being a labeled form of glucose ( Fludeoxyglucose (18 F) (FDG). Useful in differentiating ischemic from neoplastic areas.

MR SPECTROGRAPHY non-invasive, ionizing radiation free analytical technique that has been used to study metabolic changes in brain tumors, strokes, seizure disorders, Alzheimer's disease, depression and other diseases affecting the brain.

MR TRACTOGRAPHY Visual representation of neural tracts

NERVE AND MUSCLE BIOPSY

HORMONAL ASSAY