FMGE 2023 Practice Questions

Q: In the sagittal section of the brain given below the colored area represents the paracentral lobule. Which of the following structures are affected in a lesion to this area?

Perineum and leg. ***Perineum and leg*** - The **paracentral lobule**, located on the medial surface of the cerebral hemisphere, contains the primary motor and somatosensory cortical areas for the contralateral **leg**, **foot**, and **perineum**. - A lesion in this area, often due to an **anterior cerebral artery (ACA) stroke**, typically results in motor and sensory deficits in the contralateral leg and foot, and may also cause **urinary incontinence** due to involvement of the cortical micturition center. *Scapular region and neck* - The cortical representations for the scapular region and neck are located on the **superolateral surface** of the precentral and postcentral gyri, not on the medial surface where the paracentral lobule lies. - These areas are supplied by the **middle cerebral artery (MCA)**, not the ACA. *Trunk and shoulder* - According to the **motor and sensory homunculus**, the trunk and shoulder areas are located more superiorly and laterally on the cerebral cortex, lateral to the paracentral lobule. - A lesion affecting these areas would involve the superolateral convexity of the hemisphere, which has a different vascular supply (MCA). *Face and neck* - The cortical areas for the face and neck are situated on the **inferolateral aspect** of the precentral and postcentral gyri. - Lesions here are characteristic of an **MCA stroke** and would result in contralateral facial weakness and sensory loss, sparing the lower limbs.

Q: What is the most common cause of death in children with Diabetic ketoacidosis?

Cerebral edema. ***Cerebral edema*** - It is the **most common cause of mortality** in pediatric DKA, occurring in 0.5-1% of cases with a mortality rate of 20-25% [1] - Occurs due to rapid changes in **plasma osmolality** during treatment - the rapid decrease of blood glucose and effective osmolarity creates an osmotic gradient, causing fluid shifts into brain cells - Leads to potentially fatal **intracranial pressure** elevation with clinical features of headache, altered mental status, bradycardia, and respiratory depression - Risk factors include: new-onset diabetes, younger age, severe acidosis, and rapid fluid administration *Hypokalemia* - Potassium levels often drop dramatically during DKA treatment as insulin drives potassium into cells, potentially causing life-threatening **cardiac arrhythmias** [1] - This complication is highly anticipated and routinely managed by **potassium replacement therapy** with close monitoring [3] - While potentially fatal if unrecognized, it is a **preventable and treatable** condition with proper electrolyte management *Dehydration* - Severe dehydration causing **hypovolemic shock** is a major factor contributing to morbidity in DKA [2] - Effectively managed by aggressive **IV fluid resuscitation** with careful monitoring [3] - In treated pediatric DKA, the failure leading to death is typically the development of **cerebral edema** rather than persistent volume depletion [1] *Sepsis* - While sepsis can precipitate DKA, it is an underlying **trigger** or precipitating factor, not the direct physiological cause of death during DKA itself - The overwhelming fatality **in** pediatric DKA (as opposed to from the precipitating illness) is generally attributed to **cerebral edema** from rapid fluid shifts leading to central nervous system complications [1]

Question 1

In the sagittal section of the brain given below the colored area represents the paracentral lobule. Which of the following structures are affected in a lesion to this area?

Accepted Answer

Perineum and leg

Answer

Face and neck

Answer

Trunk and shoulder

Answer

Scapular region and neck

Question 2

What is the most common cause of death in children with Diabetic ketoacidosis?

Accepted Answer

Cerebral edema

Answer

Hypokalemia

Answer

Dehydration

Answer

Sepsis

FMGE 2023

Anatomy

Internal Medicine