Pediatric Radiology Practice Questions

Q: The "triangular cord sign" on ultrasonography is indicative of which condition in a neonate?

Biliary atresia. **Explanation:** The **triangular cord sign** is a highly specific ultrasonographic finding for **Biliary Atresia (BA)**. It represents a cone-shaped or triangular fibrotic mass of the cranial part of the extrahepatic biliary tree. On ultrasound, it appears as an echogenic (hyperechoic) area located anterior to the bifurcation of the portal vein. A thickness of **>4 mm** is generally considered diagnostic. **Why Biliary Atresia is correct:** In BA, there is progressive fibro-obliterative destruction of the extrahepatic biliary system. The "triangular cord" is the sonographic visualization of this fibrous remnant at the porta hepatis. When combined with an absent or small, irregular gallbladder (ghost gallbladder sign), it is a pathognomonic finding. **Why other options are incorrect:** * **Galactosemia:** This is a metabolic disorder. While it can cause neonatal jaundice and hepatomegaly, it does not involve anatomical obliteration of the bile ducts; diagnosis is via enzyme assays and urine reducing sugars. * **Hepatitis (Neonatal):** This is the primary differential for BA. On ultrasound, neonatal hepatitis typically shows a patent biliary tree and a normal-sized gallbladder. It lacks the specific fibrous cord seen in BA. **High-Yield Clinical Pearls for NEET-PG:** * **Gold Standard Diagnosis:** Intraoperative Cholangiogram (IOCG). * **Best Initial Screening:** Ultrasound (looking for the triangular cord sign). * **Functional Imaging:** HIDA scan (shows uptake by the liver but **no excretion** into the bowel even after 24 hours). * **Surgical Management:** Kasai Procedure (Hepatoportoenterostomy), ideally performed before 60 days of life. * **Liver Biopsy:** Shows bile duct proliferation and portal fibrosis.

Q: An X-ray of a neonate's abdomen reveals which of the following findings?

Pneumatosis intestinalis. ***Pneumatosis intestinalis*** - Appears as **linear or cystic gas collections** within the bowel wall on X-ray, indicating **necrotizing enterocolitis (NEC)**. - Often accompanied by **portal venous gas** and **pneumoperitoneum** in severe cases, representing bowel wall necrosis. *Duodenal atresia* - Characterized by the classic **"double bubble" sign** with **gastric and duodenal distension** only. - Shows **absence of distal bowel gas** due to complete obstruction at the duodenum. *Jejunal atresia* - Presents with **"triple bubble" sign** or **multiple dilated bowel loops** proximal to the obstruction. - Shows **minimal to absent distal bowel gas** with dilated proximal small bowel loops. *Hirschsprung's disease* - Demonstrates **dilated proximal colon** with **narrow distal rectosigmoid segment** creating a **transition zone**. - Shows **retained stool** in dilated bowel with **absence of normal rectal gas shadow**.

Q: What could be the cause of the condition highlighted by the arrow in the occlusal radiograph of an 8-year-old child?

Mesiodens. ***Mesiodens*** - **Mesiodens** is the most common **supernumerary tooth** found in the **maxillary midline**, typically visible on occlusal radiographs in children. - It appears as an **extra tooth structure** between the central incisors and can cause **delayed eruption** or **displacement** of permanent teeth. *Non-vital tooth* - A **non-vital tooth** would show signs of **pulpal necrosis** or **periapical pathology** but would not appear as an additional tooth structure. - This condition involves **existing teeth** losing vitality, not the presence of **supernumerary teeth**. *Impacted tooth* - An **impacted tooth** is part of the **normal dentition** that fails to erupt properly due to **lack of space** or **obstruction**. - It would not appear as an **extra tooth** but rather as a **displaced normal tooth** in an abnormal position. *Ghost tooth* - **Ghost tooth** refers to **regional odontodysplasia**, characterized by **hypocalcified** and **hypoplastic** tooth structure with a **ghostly appearance**. - This condition affects **existing teeth** making them appear **radiolucent** and malformed, not creating **additional tooth structures**.

Q: The lung-head ratio is useful in the diagnosis of which of the following conditions?

Congenital diaphragmatic hernia. **Explanation:** The **Lung-to-Head Ratio (LHR)** is a critical prenatal ultrasonographic parameter used primarily to assess the severity of pulmonary hypoplasia in fetuses with **Congenital Diaphragmatic Hernia (CDH)**. In CDH, abdominal viscera herniate into the thoracic cavity, compressing the developing lungs. The LHR is calculated by measuring the area of the contralateral (healthy) lung at the level of the four-chamber view of the heart and dividing it by the fetal head circumference. A lower LHR indicates more severe pulmonary hypoplasia and correlates with a poorer prognosis and higher need for postnatal ECMO (Extracorporeal Membrane Oxygenation). **Analysis of Incorrect Options:** * **Sequestration:** While this is a bronchopulmonary malformation, it is characterized by non-functional lung tissue with an anomalous systemic blood supply. Diagnosis is usually based on identifying the feeding systemic artery via Doppler, not LHR. * **Ileal Atresia:** This is a distal bowel obstruction. Antenatal ultrasound typically shows dilated bowel loops and polyhydramnios, but it does not involve lung measurement. * **Esophageal Atresia:** This is suggested prenatally by a "small or absent stomach bubble" and polyhydramnios. It does not directly impact lung volume in a way that requires LHR measurement. **High-Yield Clinical Pearls for NEET-PG:** * **Most common type of CDH:** Bochdalek hernia (Posterolateral, more common on the **Left** side). * **Morgagni Hernia:** Anterior/Retrosternal, usually occurs on the right side. * **Observed/Expected LHR (o/e LHR):** A more modern refinement of LHR that accounts for gestational age to better predict survival. * **Scaphoid abdomen:** A classic physical exam finding in newborns with CDH.

Q: Given the provided X-ray of a neonate, what is the diagnosis?

Congenital diaphragmatic hernia. ***Congenital diaphragmatic hernia*** - Classic neonatal chest X-ray shows **bowel loops in the thoracic cavity** with **mediastinal shift** away from the affected side, typically left-sided. - Associated with **pulmonary hypoplasia** and immediate respiratory distress in newborns due to lung compression. *Malrotation* - Primarily an **abdominal condition** affecting bowel positioning around the **superior mesenteric artery**. - Chest X-ray would be normal; diagnosis requires **upper GI series** showing abnormal duodenal positioning. *Pulmonary sequestration* - Shows a **well-defined lung mass** with abnormal **systemic arterial supply** from the aorta. - Does not cause **bowel loops in chest** or immediate severe respiratory distress in neonates. *Pneumatoceles* - Appear as **thin-walled air-filled cysts** within the lung parenchyma, typically following pneumonia. - Do not show **bowel gas patterns** in the chest or cause mediastinal shift.

Q: Which imaging modality is considered the gold standard for diagnosing hypertrophic pyloric stenosis?

Ultrasonography (USG). **Explanation:** **Hypertrophic Pyloric Stenosis (HPS)** is a condition characterized by the hypertrophy of the circular muscle layers of the pylorus, leading to gastric outlet obstruction. **1. Why Ultrasonography (USG) is the Gold Standard:** USG is the investigation of choice because it is non-invasive, avoids ionizing radiation, and allows for real-time visualization of the pyloric muscle. The diagnostic criteria on USG are highly specific: * **Pyloric muscle thickness:** >3 mm (most sensitive) * **Pyloric channel length:** >14 mm * **Pyloric diameter:** >10 mm * **Target Sign/Donut Sign:** Seen on transverse sections. **2. Why other options are incorrect:** * **CT Scan & MRI:** These are expensive, time-consuming, and often require sedation in infants. They are unnecessary because USG provides superior detail of the pyloric muscle. * **X-ray Abdomen:** While it may show a "single bubble" (distended stomach) or a "caterpillar sign" (hyperperistaltic waves), it is non-specific and cannot confirm the diagnosis of muscle hypertrophy. **Clinical Pearls for NEET-PG:** * **Classic Presentation:** A 3–6 week-old male infant with **non-bilious, projectile vomiting** and a palpable "olive-shaped" mass in the epigastrium. * **Metabolic Profile:** Hypochloremic, hypokalemic, metabolic alkalosis with **paradoxical aciduria** (High-yield). * **Barium Swallow (if USG is inconclusive):** Shows the "String sign" (narrowed canal), "Beak sign," or "Shoulder sign." * **Management:** Initial stabilization with IV fluids (Normal Saline) followed by **Ramstedt’s Pyloromyotomy**.

Q: What is the investigation of choice for posterior urethral valve?

Micturition cystourethrogram. **Explanation:** **Posterior Urethral Valve (PUV)** is the most common cause of lower urinary tract obstruction in male infants. It involves obstructing mucosal folds in the prostatic urethra. **1. Why Micturition Cystourethrogram (MCUG/VCUG) is the Correct Answer:** MCUG is the **gold standard** and investigation of choice because it captures the anatomy during the voiding phase. The classic findings on MCUG include: * **Dilatation and elongation of the posterior urethra** (proximal to the valve). * A sharp transition to a narrow caliber in the anterior urethra. * Secondary changes like a "Christmas tree" bladder (trabeculations) and **vesicoureteral reflux (VUR)**, which is seen in approximately 50% of cases. **2. Why Other Options are Incorrect:** * **Retrograde Urethrography (RGU):** This is primarily used to evaluate anterior urethral strictures in adults. It involves injecting dye against the flow of urine, which may fail to demonstrate the valve mechanism or the dilated posterior urethra effectively. * **Ultrasound:** While often the initial screening tool (showing bilateral hydronephrosis or a thick-walled bladder), it cannot definitively diagnose the valve or its exact location. The "keyhole sign" on prenatal USG is suggestive but not confirmatory. * **Intravenous Pyelogram (IVP):** This is rarely used in neonates due to immature renal concentrating ability and poor visualization. It does not provide the necessary detail of the urethral anatomy. **Clinical Pearls for NEET-PG:** * **Initial Management:** Catheterization (using a small feeding tube) to decompress the bladder. * **Definitive Treatment:** Endoscopic primary valve ablation (Fulguration). * **Keyhole Sign:** Refers to the dilated posterior urethra and thick-walled bladder seen on ultrasound. * **Most common cause** of chronic kidney disease (CKD) in children.

Q: The TRIANGULAR CORD Sign is seen in which condition?

Biliary Atresia. **Explanation:** The **Triangular Cord Sign** is a pathognomonic ultrasonographic finding for **Biliary Atresia**. It represents a cone-shaped or triangular fibrotic mass of the cranial part of the extrahepatic biliary tree. On ultrasound, it appears as an echogenic (hyper-echoic) area located anterior to the bifurcation of the portal vein. A thickness of **>4 mm** is considered a positive sign and is highly specific for diagnosing biliary atresia in a neonate with conjugated jaundice. **Analysis of Options:** * **Biliary Atresia (Correct):** Characterized by the obliteration of the extrahepatic biliary tree. Other USG findings include a small/absent gallbladder (Ghost Gallbladder sign) and the absence of a common bile duct. * **Caroli’s Disease:** A congenital disorder characterized by multifocal segmental dilatation of large intrahepatic bile ducts. The classic radiological sign is the **"Central Dot Sign"** (portal vein branches surrounded by dilated bile ducts). * **Serous Cystadenoma:** A benign pancreatic neoplasm. On imaging, it typically shows a **"Sunburst" calcification** or a honeycomb appearance, not related to the biliary cord. * **Hydatid of Liver:** Caused by *Echinococcus granulosus*. Key USG findings include the **"Water Lily Sign"** (detached endocyst) or the presence of daughter cysts. **NEET-PG High-Yield Pearls:** * **Gold Standard Diagnosis:** Intraoperative Cholangiogram (IOC). * **Surgery of Choice:** Kasai Procedure (Hepatoportoenterostomy), ideally performed before 60 days of life. * **Most Common Cause:** Biliary atresia is the most common cause of neonatal cholestasis requiring surgery. * **Associated Sign:** The "Ghost Gallbladder" sign (length <19 mm, irregular contour).

Q: A premature infant born at 34 weeks presented with acute onset lethargy and cessation of feeding. What is the imaging modality of choice to screen for intraventricular haemorrhage?

Transcranial USG. **Explanation:** **1. Why Transcranial USG is the Correct Choice:** In premature neonates, the **Germinal Matrix** (a highly vascularized area near the caudate nucleus) is prone to hemorrhage due to fragile vessels and impaired autoregulation. **Transcranial Ultrasonography (USG)** is the gold standard screening modality because: * **Open Fontanelle:** The anterior fontanelle acts as a perfect acoustic window to visualize the periventricular structures. * **Bedside Utility:** It is portable, allowing imaging in the NICU without moving a critically ill, unstable neonate. * **Safety:** It involves no ionizing radiation and requires no sedation. * **Sensitivity:** It is highly sensitive for detecting Germinal Matrix Hemorrhage (GMH) and grading Intraventricular Hemorrhage (IVH) using the **Papile Classification**. **2. Why Other Options are Incorrect:** * **NCCT (A):** While sensitive for blood, it involves significant ionizing radiation, which is avoided in neonates unless there is trauma or a need to rule out posterior fossa bleeds not seen on USG. * **MRI (B):** MRI is the most sensitive for white matter injury (Periventricular Leukomalacia), but it is not a screening tool. It requires transporting the infant and often necessitates sedation, making it impractical for acute screening. * **Plain Radiograph (D):** X-rays cannot visualize soft tissue structures or intracranial hemorrhages. **3. High-Yield Clinical Pearls for NEET-PG:** * **Screening Protocol:** All infants born **<30-32 weeks** or **<1500g** should undergo screening USG at 7–14 days of life. * **Acoustic Window:** The **Anterior Fontanelle** is the primary window; the Mastoid fontanelle is used to view the cerebellum. * **Grading (Papile):** * Grade I: Isolated Germinal Matrix Hemorrhage. * Grade II: IVH without ventricular dilatation. * Grade III: IVH with ventricular dilatation. * Grade IV: IVH with intraparenchymal extension.

Question 1

The "triangular cord sign" on ultrasonography is indicative of which condition in a neonate?

Accepted Answer

Biliary atresia

Answer

Galactosemia

Answer

Hepatitis

Answer

None of the above

Question 2

An X-ray of a neonate's abdomen reveals which of the following findings?

Accepted Answer

Pneumatosis intestinalis

Answer

Duodenal atresia

Answer

Jejunal atresia

Answer

Hirschsprung's disease

Question 3

What could be the cause of the condition highlighted by the arrow in the occlusal radiograph of an 8-year-old child?

Accepted Answer

Mesiodens

Answer

Non-vital tooth

Answer

Impacted tooth

Answer

Ghost tooth

Question 4

The lung-head ratio is useful in the diagnosis of which of the following conditions?

Accepted Answer

Congenital diaphragmatic hernia

Answer

Sequestration

Answer

Ileal atresia

Answer

Esophageal atresia

Question 5

Given the provided X-ray of a neonate, what is the diagnosis?

Accepted Answer

Congenital diaphragmatic hernia

Answer

Malrotation

Answer

Pulmonary sequestration

Answer

Pneumatoceles

Question 6

Which imaging modality is considered the gold standard for diagnosing hypertrophic pyloric stenosis?

Accepted Answer

Ultrasonography (USG)

Answer

CT scan

Answer

X-ray of the abdomen in supine position

Answer

MRI

Question 7

What is the investigation of choice for posterior urethral valve?

Accepted Answer

Micturition cystourethrogram

Answer

Retrograde urethrography

Answer

Ultrasound

Answer

Intravenous pyelogram (IVP)

Question 8

The TRIANGULAR CORD Sign is seen in which condition?

Accepted Answer

Biliary Atresia

Answer

Caroli's Disease

Answer

Serous Cystadenoma

Answer

Hydatid of Liver

Question 9

What is the most likely diagnosis in a child with the following Chest X-ray finding?

Accepted Answer

Tetralogy of Fallot (TOF)

Answer

Transposition of the Great Arteries (TGA)

Answer

Total Anomalous Pulmonary Venous Connection (TAPVC)

Answer

Ebstein's Anomaly

Question 10

A premature infant born at 34 weeks presented with acute onset lethargy and cessation of feeding. What is the imaging modality of choice to screen for intraventricular haemorrhage?

Accepted Answer

Transcranial USG

Answer

NCCT

Answer

MRI

Answer

Plain radiograph

Pediatric Radiology — MCQs

Pediatric Radiology — MCQs

On this page

Practice by Chapter

Want unlimited practice?