Pediatric Radiology Practice Questions

Q: Investigation of choice for the diagnosis of congenital hypertrophic pyloric stenosis is:

USG. ***USG*** - **Ultrasound** is the preferred initial imaging modality due to its non-invasiveness, lack of radiation, and high accuracy in visualizing the thickened pyloric muscle. - The classic ultrasound findings include a **pyloric muscle thickness** of ≥ 4 mm and a **pyloric channel length** of ≥ 14 mm. *Barium meal* - While a barium meal can show findings like the "string sign" or "shoulder sign," it involves **radiation exposure** and is generally considered a second-line investigation. - Its diagnostic accuracy is good, but it is less convenient and riskier than ultrasound for this condition. *Barium meal follow through* - This procedure tracks barium through the entire gastrointestinal tract, which is **excessive and unnecessary** for diagnosing pyloric stenosis, which is a localized obstruction. - It also involves significant **radiation exposure** and a prolonged examination time. *CT scan with contrast* - A **CT scan** involves significant **radiation exposure** and is not typically used for diagnosing congenital hypertrophic pyloric stenosis. - It is also less sensitive than ultrasound for visualizing the specific soft tissue changes in the pyloric muscle.

Q: What is the most common cause of periventricular calcification?

Cytomegalic infection. ***Cytomegalic infection*** - **Periventricular calcification** is a classic finding in congenital Cytomegalovirus (CMV) infection due to the virus's predilection for the **subependymal germinal matrix**. - CMV is the **most common congenital infection** and the leading infectious cause of **sensorineural hearing loss** and neurodevelopmental delay, often presenting with such calcifications. *Toxoplasmosis* - Congenital toxoplasmosis typically causes **diffuse scattered intracranial calcifications** rather than the periventricular pattern seen with CMV. - While it is a significant cause of congenital neurological damage, its calcification pattern is usually **randomly distributed** throughout the brain parenchyma. *Congenital syphilis* - Congenital syphilis primarily affects the **bones, skin, liver, and eyes**, but typically does not cause intracranial calcifications. - Neurological manifestations in congenital syphilis are more commonly related to **meningitis** or **hydrocephalus**, without characteristic calcifications. *Tuberous sclerosis* - Tuberous sclerosis causes **subependymal nodules** that may calcify and can appear in a periventricular distribution. - However, these are **hamartomas** (non-infectious lesions) and are part of a broader neurocutaneous syndrome, distinguished from CMV by associated features like **cortical tubers**, **cardiac rhabdomyomas**, and **skin findings** (ash-leaf spots, shagreen patches).

Q: A child presents with unilateral white reflex (leukocoria) and raised intraocular pressure, raising suspicion of retinoblastoma. Which of the following investigations is the most appropriate to perform?

Detailed examination under anesthesia. ***Detailed examination under anesthesia*** - A **detailed examination under anesthesia (EUA)** is crucial for accurately assessing the extent of intraocular lesions in children, particularly those with suspected retinoblastoma. It allows for a thorough and precise evaluation of tumor size, location, and multifocality that is otherwise difficult to achieve in an awake child. - EUA often includes fundus photography, ultrasonography, and sometimes anterior segment examination, all performed systematically without the child moving. It is the gold standard for **diagnosing and staging retinoblastoma**. *Ultrasound imaging of the eye* - **Ocular ultrasound** is a key component of the investigation and can help identify the intraocular mass and detect calcifications, which are characteristic of retinoblastoma. - However, ultrasound alone is often insufficient to fully characterize the tumor's extent or for precise staging, and it doesn't replace the need for direct visualization and comprehensive examination. *Measurement of intraocular pressure* - **Raised intraocular pressure** is a symptom that can be present in retinoblastoma but is not a diagnostic tool for the condition itself; it indicates secondary glaucoma due to the tumor. - While important for clinical management, measuring IOP does not directly visualize or characterize the tumor to confirm the diagnosis of retinoblastoma. *CT imaging of the orbit and head* - While **CT imaging** can detect orbital and intracranial extension of retinoblastoma, it involves **ionizing radiation**, which is a significant concern in children, especially those with an increased genetic risk for secondary cancers. - **MRI** is generally preferred over CT for assessing extraocular extension and possible central nervous system involvement due to its superior soft tissue contrast and lack of radiation exposure.

Q: Features of periostitis on X-ray of the hip in a child suggest

Syphilis. ***Syphilis*** - **Congenital syphilis** is known to cause **periostitis**, especially in long bones, which can be visualized on X-rays as new bone formation. - Features often include **widespread bony lesions**, including periosteal thickening, osteitis, and metaphysitis due to the systemic nature of the infection. *Toxoplasma (affects CNS and eyes)* - **Congenital toxoplasmosis** primarily affects the **central nervous system** (e.g., hydrocephalus, intracranial calcifications) and eyes (e.g., chorioretinitis). - It does not typically cause **periostitis** or bony changes visible on X-ray of the hip. *CMV (typically leads to systemic disease)* - **Congenital cytomegalovirus (CMV)** infection often presents with **systemic manifestations** like hepatosplenomegaly, thrombocytopenia, and neurological deficits. - While CMV can cause **bony lesions** in severe cases, classical periostitis, especially as a prominent isolated feature on hip X-ray, is not characteristic. *Rubella (primarily causes cardiac and ocular abnormalities)* - **Congenital rubella syndrome** classically involves a triad of **cardiac defects** (e.g., patent ductus arteriosus), **ocular abnormalities** (e.g., cataracts, glaucoma), and **sensorineural hearing loss**. - While it can cause some bone lesions (e.g., "celery stalk" appearance in metaphyses), **periostitis** of the hip is not a primary or common finding associated with rubella.

Q: What is the cardiothoracic ratio in children?

50-55%. ***50-55%*** - The normal **cardiothoracic ratio** in children is generally considered to be **50-55%** on a **posterior-anterior (PA) chest X-ray**. - In **infants and young children (under 2 years)**, the ratio can be **up to 55-60%** due to relatively larger cardiac size and more horizontal positioning of the heart. - In **older children (over 2 years)**, the normal ratio approaches adult values of **less than 50%**. - A ratio consistently greater than 55% could indicate **cardiomegaly**, which warrants further investigation. *30-35%* - This range is typically too low and would suggest an **unusually small heart** for the chest cavity, which is not a normal finding in children. - A very low ratio like this is not characteristic of the pediatric population and may indicate technical issues with the radiograph. *40-45%* - While this range approaches normal values for **older children and adults**, it is generally on the lower side for the average **pediatric cardiothoracic ratio**. - This percentage alone is not the best answer when considering the entire pediatric age spectrum, including infants and younger children. *60-65%* - A cardiothoracic ratio in this range would typically be considered **abnormal** and indicative of **cardiomegaly** in children beyond infancy. - Such an elevated ratio would suggest an enlarged heart, prompting further cardiac evaluation including **echocardiography** to assess for structural heart disease.

Question 1

Investigation of choice for the diagnosis of congenital hypertrophic pyloric stenosis is:

Accepted Answer

USG

Answer

Barium meal

Answer

Barium meal follow through

Answer

CT scan with contrast

Question 2

What is the most common cause of periventricular calcification?

Accepted Answer

Cytomegalic infection

Answer

Toxoplasmosis

Answer

Congenital syphilis

Answer

Tuberous sclerosis

Question 3

A child presents with unilateral white reflex (leukocoria) and raised intraocular pressure, raising suspicion of retinoblastoma. Which of the following investigations is the most appropriate to perform?

Accepted Answer

Detailed examination under anesthesia

Answer

Ultrasound imaging of the eye

Answer

Measurement of intraocular pressure

Answer

CT imaging of the orbit and head

Question 4

Features of periostitis on X-ray of the hip in a child suggest

Accepted Answer

Syphilis

Answer

Toxoplasma

Answer

CMV

Answer

Rubella

Question 5

What is the cardiothoracic ratio in children?

Accepted Answer

50-55%

Answer

30-35%

Answer

40-45%

Answer

60-65%

Pediatric Radiology — MCQs

Pediatric Radiology — MCQs

On this page

Practice by Chapter

Want unlimited practice?