Neuroimaging Techniques Quiz

Assessment of Neuro Function

• CT: X-ray imaging showing cross-sectional brain views. A rotating machine scans the patient's head. The procedure is painless and quick, requiring the patient to remain very still. No talking or face movements are allowed. Radiation is used. Remember IV contrast precautions and aftercare.
• MRI: Powerful magnetic imaging for detailed brain images. Particularly useful for diagnosing brain tumors, stroke, and multiple sclerosis. No radiation is used. The procedure can take an hour or more, and is generally not used for emergencies. Remove all metal objects, including earrings and medication patches.
• PET: Organ function imaging. Patients inhale or are injected with radioactive gas. Measures blood flow and brain function which can be used to identify Alzheimer's disease, tumors, and lesions. Potential side effects include dizziness, lightheadedness, and headaches.
• Cerebral Angiography: X-ray study of cerebral circulation utilizing a contrast agent injected into a selected artery. Helpful in diagnosing vascular diseases. Similar to a cardiac catheterization, with puncture in the carotid, femoral, or arterial arteries. Contrast is essential in assessing kidney function. Pre-op and post-op site monitoring and comparison with the opposite extremity is necessary.
• Myelography: X-ray image of the spinal subarachnoid space after contrast injection via lumbar puncture. Used to identify spinal cord abnormalities such as tumors, discs, lesions, and cysts. Post-procedure, elevate the head of the bed 30-45 degrees for 4-24 hours, ensuring adequate hydration to prevent lumbar puncture headache). Nausea, vomiting, headache, fever, stiff neck, seizures, and loss of consciousness or changes in LOC are possible complications.
• Electroencephalography (EEG): Noninvasive assessment of cerebral electrical activity using electrodes placed on the scalp or within brain tissues. EEG is used for analyzing seizure activity, confirming mental disorders, and determining brain death. The process is painless. A standard EEG lasts 45-60 minutes. Avoid caffeine and other stimulants prior to the procedure.
• Electromyography (EMG): Determines neuromuscular disorders by inserting needles into skeletal muscles to measure electrical potentials. The needle insertion technique is similar to an intramuscular (IM) injection..
• Doppler: Noninvasive ultrasound imagery, performed at the patient's bedside, evaluates cranial vessel function. Dopplers are used on the neck and eye orbits.
• Evoked Potential Studies: External stimuli are applied to specific peripheral receptors (e.g., flashing lights). An EEG device monitors the response. The patient must remain still throughout the procedure.
• Lumbar Puncture: Used for detecting syphilis, meningitis, infections, and malignancies. CSF pressure assessment and contrast administration for diagnostic procedures or direct drug/chemotherapy administration into CSF are potential applications.

Increased Intracranial Pressure (IICP)

• Normal ICP: 10-20 mm Hg.
• IICP: Compression of brain tissues and blood vessels due to increased pressure within the skull. Causes include reduced blood flow, cerebral edema, and abnormal autoregulation,
• Early Signs (IICP): Changes in level of consciousness (LOC). PERRLA changes, one-sided weakness, or persistent headache that worsens with movement.
• Late Signs (IICP): Cushing's triad (hypertension, bradycardia, bradypnea), projectile vomiting, worsening LOC, loss of brainstem reflexes.
• IICP Management: Prioritizing airway management and ensuring sufficient oxygenation. Implementing measures to maintain cerebral perfusion pressure (CPP) within normal ranges(70-100 mmHg).

Other Neuro Conditions

• Strokes: Differentiating ischemic (clot blocking blood flow) and hemorrhagic (bleeding in the brain) strokes. The types, signs/symptoms, treatment, and complications of each are important considerations. Important factors in determining treatment are whether a stroke was caused by injury, and whether the patient is a candidate for TPA (tissue plasminogen activator).
• Head Injuries: Acute and secondary types of brain injuries. Important to recognize the different types of injuries and the potential complications are important to consider in assessing any head injury patient. Intracranial hemorrhages, such as epidural and subdural hematomas, require critical assessment.
• Seizures: Understanding the types (focal, generalized), pre-ictal and post-ictal phases of seizure, and appropriate treatments, especially in cases of status epileptics
• Meningitis: Inflammation of the meninges causing headache, stiff neck, Kernig, and Brudzinski signs are important diagnostic indicators.
• Brain Abscess: Collection of infectious material within the brain, most commonly arising from untreated otitis media or rhinosinusitis.
• Myasthenia Gravis: Autoimmune disease affecting the myoneural junction. Diagnosis often involves a Tensilon test. Causes include double vision, ptosis, facial muscle weakness, difficulty swallowing and dysphonia, and possible complications. This is a progressive disease.
• Guillain-Barre Syndrome: Autoimmune disorder often following a viral infection. Results in ascending paralysis, threatening respiratory function.
• Other Conditions: Various other neurological conditions, such as Bell's Palsy, Tic Douloureux, and specific types of dementia like Alzheimers and Parkinsons, necessitate a complete understanding of each condition, clinical presentation, diagnostic methods, treatment, and prognosis.

Test your knowledge on various neuroimaging techniques including CT, MRI, PET, and cerebral angiography. This quiz covers the procedures, uses, and precautions associated with each imaging method. Gain a deeper understanding of how these techniques assist in diagnosing neurological conditions.