NCS Traumatic Brain Injury 3 — Questions and Answers
Question 1: Diffuse axonal injury (DAI) after TBI is best visualized on which MRI sequence?
- T1-weighted imaging
- FLAIR (Fluid-Attenuated Inversion Recovery)
- Susceptibility-weighted imaging (SWI) (Correct answer)
- Diffusion tensor imaging (DTI)
Correct answer: Susceptibility-weighted imaging (SWI)
SWI is the most sensitive conventional MRI sequence for detecting microhemorrhages associated with DAI due to its sensitivity to blood products and iron.
Question 2: In the acute management of severe TBI, the Brain Trauma Foundation recommends maintaining cerebral perfusion pressure (CPP) within which range?
- 40–50 mmHg
- 50–70 mmHg (Correct answer)
- 70–90 mmHg
- 90–110 mmHg
Correct answer: 50–70 mmHg
The Brain Trauma Foundation guidelines recommend targeting CPP of 60–70 mmHg (50–70 mmHg range accepted) to optimize cerebral blood flow while avoiding secondary injury.
Question 3: Paroxysmal sympathetic hyperactivity (PSH) after severe TBI is characterized by episodic increases in which combination of signs?
- Heart rate, blood pressure, temperature, sweating, and posturing (Correct answer)
- Heart rate, intracranial pressure, pupil dilation, and bradypnea
- Blood pressure, respiratory rate, miosis, and salivation
- Temperature, heart rate, urinary retention, and bradycardia
Correct answer: Heart rate, blood pressure, temperature, sweating, and posturing
PSH is defined by simultaneous paroxysmal increases in heart rate, blood pressure, temperature, diaphoresis, and tachypnea, often accompanied by extensor posturing.
Question 4: A 30-year-old patient with moderate TBI develops elevated serum sodium (160 mEq/L) with large urine output and low urine osmolality 5 days post-injury. The most likely diagnosis is:
- Syndrome of inappropriate antidiuretic hormone (SIADH)
- Cerebral salt wasting (CSW)
- Central diabetes insipidus (CDI) (Correct answer)
- Hyperaldosteronism
Correct answer: Central diabetes insipidus (CDI)
Central diabetes insipidus results from hypothalamic/pituitary damage causing ADH deficiency, leading to hypernatremia, polyuria, and dilute urine after TBI.
Question 5: The Disorders of Consciousness Scale (DOCS) is designed to assess patients at which level of recovery?
- Rancho Los Amigos Levels I–III (coma to localized response) (Correct answer)
- Rancho Los Amigos Levels IV–VI (confusion to appropriate behavior)
- Rancho Los Amigos Levels VII–VIII (automatic to purposeful behavior)
- Post-acute community reintegration
Correct answer: Rancho Los Amigos Levels I–III (coma to localized response)
The DOCS is a standardized scale used with patients in coma or vegetative/minimally conscious states (Rancho Levels I–III) to assess and track sensory responsiveness.
Question 6: Which finding on the Glasgow Coma Scale (GCS) at 24 hours post-injury is most predictive of poor outcome in adults with severe TBI?
- Motor score of 1 (no motor response) (Correct answer)
- Eye-opening score of 2 (to pain)
- Verbal score of 2 (incomprehensible sounds)
- Total GCS score of 8
Correct answer: Motor score of 1 (no motor response)
A motor score of 1 (no motor response) on the GCS at 24 hours is one of the strongest single predictors of poor neurological outcome after severe TBI.
Question 7: Post-traumatic hydrocephalus (PTH) after severe TBI most commonly presents as which clinical triad?
- Headache, papilledema, and vomiting
- Cognitive decline, gait disturbance, and urinary incontinence (Correct answer)
- Seizures, focal weakness, and aphasia
- Fever, nuchal rigidity, and photophobia
Correct answer: Cognitive decline, gait disturbance, and urinary incontinence
Normal pressure hydrocephalus-type presentation (cognitive decline, gait ataxia, urinary incontinence) is the classic triad of post-traumatic communicating hydrocephalus.
NCS Traumatic Brain Injury 3
Diffuse axonal injury (DAI) after TBI is best visualized on which MRI sequence?