PRELIMS: Diagnostic Test

Question 1

Skull X-Ray Uses?

Answer 1

Detect fractures, dislocations, lytic lesions, blastic lesions, and foreign bodies.

Question 2

Spine X-Ray: Cervical?

Answer 2

: Assess curve, alignment, vertebra, IV discs, foramina, fractures, dislocations, osteophytes, spondylosis, spondylolisthesis, DDD, foreign bodies, fusion, scoliosis.

Question 3

Spine X-Ray: Thoracic & Lumbar?

Answer 3

Assess similar features as cervical; focus on fractures, alignment, and degenerative changes.

Question 3

CT Scan Use?

Answer 3

Identify acute hemorrhage, bones of skull/spine; limitations in posterior fossa.

Question 4

MRI: Lumbar?

Answer 4

Focuses on lumbar vertebrae, disc herniations, and spinal canal.

Question 4

CT Scan Advantages?

Answer 4

: Cost-effective, fast, widely available; useful for acute stroke, head injury, infections, calcifications.

Question 4

Contrast-Enhanced CT Uses?

Answer 4

: Breakdown of BBB, detect tumors, infections, inflammatory conditions, rule out cerebral metastasis.

Question 4

CT Scan Limitations?

Answer 4

Limited in posterior fossa; not ideal for some detailed soft tissue evaluations.

Question 5

CT Angiography (CTA) Advantages?

Answer 5

Identifies vascular abnormalities, available technology, requires less specialized skill.

Question 5

CT Scan Uses?

Answer 5

Cost-effective, fast, widely available. Good for acute stroke, head injury, infections, calcifications. Useful for neurologically unstable patients, mechanical ventilator use, metallic implants, pacemakers.

Question 6

Contrast-Enhanced CT Uses?

Answer 6

Detects breakdown of BBB, brain/spinal tumors, infections, inflammatory conditions, rules out cerebral metastasis.

Question 7

MRI: Gold Standard for?

Answer 7

Intracranial, spinal, multiple sclerosis (MS).

Question 7

MRI: Cervical/Thoracic Spine?

Answer 7

Evaluates spinal cord, vertebrae, and surrounding structures for lesions and alignment.

Question 8

MRI-DWI Use?

Answer 8

Acute stroke imaging; detects cerebral ischemia.

Question 9

MRI Disadvantages?

Answer 9

Requires patient cooperation, metal implants, pregnancy concerns, claustrophobia.

Question 9

Magnetic Resonance Spectroscopy (MRS) Uses?

Answer 9

Assesses metabolic disorders, MELAS, MS plaques, hippocampal seizure foci, degenerative diseases, neoplasms. Measures choline, NAA, lactate levels.

Question 9

Single Photon Emission Computed Tomography (SPECT) Use?

Answer 9

: Tomographic imaging of injected radioisotopes for cerebral perfusion. Widely available, cost-effective, useful post-tracer injection.

Question 9

Functional MRI (fMRI) Use?

Answer 9

Maps cerebral activation; assesses motor, sensory, language functions. Guides surgery, embolization, radiation therapy, stroke recovery, cognitive changes.

Question 9

Magnetic Resonance Angiography (MRA) Use?

Answer 9

Evaluates intracranial circulation patency, stroke/TIA, venous sinus thrombosis, AVM, vascular tumors, altered hemodynamics.

Question 10

MRA vs. Other Techniques?

Answer 10

CTA: Non-invasive, no specialized catheter skills, avoids neuro complications. MRI: Better soft tissue contrast, multiplanar imaging, demonstrates physiological processes, visualizes posterior fossa/intra-spinal lesions.

Question 10

Lumbar Tap/Puncture Use?

Answer 10

Analyzes cerebrospinal fluid (CSF), drains CSF, and reduces CSF pressure. Normal pressure: 100-150 mm CSF.

Question 10

MRI Advantages?

Answer 10

Greater soft tissue contrast, multiplanar, demonstrates physiological processes, lacks ionizing radiation.

Question 11

Myelogram Use?

Answer 11

Screens spinal canal and cord. Detects root compression. Complications: arachnoiditis, subdural injection, hematoma, spinal tumor impaction.

Question 11

: Positron Emission Tomography (PET) Use?

Answer 11

Tomographic imaging of injected radioisotopes. Measures cerebral blood flow (CBF), oxygen utilization, protein synthesis, and turnover.

Question 11

Transcranial Ultrasonography Use?

Answer 11

Evaluates hemodynamics, vasospasm, and stenosis.

Question 11

Catheter Angiography Use?

Answer 11

Detailed evaluation of intracranial vascular disease. Preoperative assessment of intracranial vessels. Diagnosis of ischemic stroke in hyperacute phase.

Question 12

Evoked Potentials (EP) Use?

Answer 12

Assesses CNS activity in response to specific stimuli. Extends neurologic examination.

Question 12

Intracranial Pressure Monitoring Use?

Answer 12

Monitors and treats increased intracranial pressure (ICP). Useful in conditions like normal pressure hydrocephalus (NPH), post-op edema, traumatic hematoma.

Question 12

CT Myelogram Use?

Answer 12

Identifies compressive and expanding lesions in the spine.

Question 12

Needle Biopsy: Muscle Indications?

Answer 12

Limb weakness, infantile hypotonia, exercise intolerance, myoglobinuria, cramps.

Question 12

Nerve Biopsy Use?

Answer 12

Diagnoses peripheral neuropathy. Sural nerve is most commonly studied.

Question 12

Electroencephalogram (EEG) Use?

Answer 12

Measures brain electrical activity. Useful for diagnosing epilepsy and in obtunded patients.

Question 12

Spinal Fluid Analysis Components?

Answer 12

Bacteriological, biochemical protein (0.15-0.45 g/l), biochemical glucose (0.45-0.79 g/l).

Question 12

Electromyography-Nerve Conduction Velocity Studies (EMG-NCV) Use?

Answer 12

Assesses nerve and muscle activity, NMJ function. NCV measures conduction in nerves; EMG measures electrical activity in muscles.

Question 12

Skin Punch Biopsy Use?

Answer 12

Assesses extensive cutaneous sensory and autonomic nerves. Detects painful or small-fiber neuropathy. Minimally invasive, can be taken from multiple sites.

Question 12

Excision Biopsy: Muscle Locations?

Answer 12

Proximal: vastus lateralis, biceps. Distal: gastrocnemius, tibialis anterior, peroneus brevis.