Future of AI in Radiology — MCQs
What is the investigation of choice for diagnosing a stress fracture?
A GSP4 woman comes for routine sonography for the first time. She has four daughters and expresses a desire for a boy this time, asking for sex determination. To abide by ethical guidelines, what should you do?
What is the investigation of choice for whole body imaging in metastatic breast cancer?
Which of the following statements about the DOTS treatment for tuberculosis is correct?
Based on the provided image, which of the following is the correct diagnosis?
Gold standard investigation for breast carcinoma screening in a patient with silicone breast implants
What is the classification of intelligence corresponding to an IQ score of 90-109?
Radiation-induced necrosis can be diagnosed by:
A research team develops an AI algorithm using 100,000 CT scans from multiple institutions. The algorithm shows excellent performance (AUC 0.96) but requires extensive computational resources. To deploy it in resource-limited settings, they propose model compression techniques. Evaluate the potential trade-offs and propose the most balanced approach.
A radiology department is evaluating two AI algorithms for fracture detection. Algorithm A has AUC-ROC of 0.95, while Algorithm B has AUC-ROC of 0.92 but provides explainable results showing which image regions influenced its decision. Considering clinical implementation and medicolegal aspects, which statement best evaluates the choice?
Future of AI in Radiology Indian Medical PG Practice Questions and MCQs
Question 1: What is the investigation of choice for diagnosing a stress fracture?
- A. X-ray
- B. CT scan
- C. MRI (Correct Answer)
- D. Bone scan
Explanation: ***MRI*** - **Magnetic Resonance Imaging (MRI)** is the most sensitive and specific imaging modality for diagnosing **stress fractures**, especially in their early stages. - It can detect **bone marrow edema** and **periosteal reactions** indicative of stress injury before cortical changes are visible on plain radiographs. *X-ray* - **X-rays** are often the initial investigation, but they have low sensitivity for **stress fractures** in the early stages as bone changes may not be apparent for several weeks. - A positive X-ray for stress fracture typically shows a **sclerotic line** or **periosteal reaction**, but this indicates a more advanced injury. *CT scan* - **CT scans** provide excellent detail of **cortical bone** and can detect subtle fractures not seen on X-rays. - While more sensitive than X-rays, CT has **higher radiation exposure** and is generally less sensitive than MRI for early detection of **bone marrow edema** associated with stress injuries. *Bone scan* - **Bone scans** (scintigraphy) are highly sensitive for detecting increased **osteoblastic activity** associated with stress fractures. - However, they are **less specific** as various conditions can cause increased uptake, and they do not provide detailed anatomical information, making MRI superior for definitive diagnosis and staging.
Question 2: A GSP4 woman comes for routine sonography for the first time. She has four daughters and expresses a desire for a boy this time, asking for sex determination. To abide by ethical guidelines, what should you do?
- A. Check routine ANC and sex for developmental abnormalities and do not reveal gender to the patient (Correct Answer)
- B. Check routine ANC and sex for developmental abnormalities and do reveal gender to the patient
- C. Do reveal gender if a girl
- D. Check only routine ANC, do not check sex
Explanation: ***Check routine ANC and sex for developmental abnormalities and do not reveal gender to the patient*** - It is **illegal** and **unethical** to reveal the sex of the fetus in many countries, including India, to prevent **sex-selective abortions**. - The primary purpose of a routine antenatal ultrasound is to assess fetal **health** and **developmental abnormalities**, not to determine sex for parental preference. *Check routine ANC and sex for developmental abnormalities and do reveal gender to the patient* - Revealing the gender to the patient directly facilitates **sex-selective abortion**, which is medically unethical and illegal due to the potential for harm to the fetus and society. - This practice would violate the **Pre-Conception and Pre-Natal Diagnostic Techniques (PCPNDT) Act** in India, which prohibits gender determination. *Do reveal gender if a girl* - Revealing the gender, regardless of whether it is a boy or a girl, can lead to **gender-biased selective abortions**, particularly in cultures with a strong preference for male offspring. - This action undermines the ethical principles of **non-maleficence** and **justice** by potentially facilitating harm based on gender preference. *Check only routine ANC, do not check sex* - While the primary focus is routine antenatal care, avoiding the assessment of fetal sex entirely could lead to **missing potential developmental abnormalities** that might be identifiable through observation of external genitalia. - A thorough ultrasound examination routinely includes a visual check of fetal anatomy, which can incidentally reveal gender, but this information should not be shared with the parents for selection purposes.
Question 3: What is the investigation of choice for whole body imaging in metastatic breast cancer?
- A. Angiography
- B. Venography
- C. Magnetic Resonance Imaging
- D. CT Scan (Correct Answer)
Explanation: ***CT Scan (Correct answer for NEET 2013)*** - **Contrast-enhanced CT scan** was the standard imaging modality for **whole-body staging** in metastatic breast cancer at the time of this exam (2013). - CT offers **excellent spatial resolution** for detecting metastases in **bone, lung, liver, and lymph nodes**. - It is widely available, relatively quick, and provides comprehensive anatomical information. - **Modern Update:** While CT was the standard in 2013, **PET-CT (FDG-PET/CT) is now considered the gold standard** for whole-body staging in metastatic breast cancer due to its combined metabolic and anatomical imaging capabilities. However, PET-CT was not among the options in this historical question. *Magnetic Resonance Imaging* - **MRI** is highly sensitive for specific sites, particularly for **brain metastases** and **bone metastases (especially spine and bone marrow)**. - **Whole-body MRI** protocols are emerging but require longer acquisition times and specialized equipment. - Not ideal as a single first-line modality for comprehensive whole-body staging compared to CT (or modern PET-CT). *Angiography* - **Angiography** is an invasive vascular imaging procedure used to visualize **arterial blood flow**. - It has **no role in routine metastatic screening or staging** of breast cancer. - Reserved for specific indications like preoperative vascular mapping or interventional procedures. *Venography* - **Venography** specifically visualizes **venous structures** and is used to detect venous thrombosis or venous obstructions. - It is **not applicable** for detecting solid organ metastases, bone lesions, or lymph node involvement in cancer staging.
Question 4: Which of the following statements about the DOTS treatment for tuberculosis is correct?
- A. Case finding 80%, cure rate 85%
- B. Case finding 80%, cure rate 80%
- C. Case finding 70%, cure rate 75%
- D. Case finding 70%, cure rate 85% (Correct Answer)
Explanation: ***Case finding 70%, cure rate 85%*** - The **DOTS strategy** set a global target of detecting at least **70% of new sputum smear-positive TB cases** and curing at least **85% of these cases**. - Achieving these targets was considered crucial for controlling the spread of **tuberculosis** at a population level. *Case finding 80%, cure rate 85%* - While a **cure rate of 85%** is a key target of the DOTS strategy, the **case finding target was not 80%**. - Setting a higher case finding target might be desirable, but the **established goal** for DOTS was slightly lower to be more achievable. *Case finding 80%, cure rate 80%* - Neither the **case finding target nor the cure rate target** for DOTS was 80%. - The **cure rate target** was specifically emphasized as being higher to ensure effective treatment outcomes and prevent drug resistance. *Case finding 70%, cure rate 75%* - While **case finding 70%** aligns with the DOTS target, the **cure rate target was higher than 75%**. - A lower cure rate would indicate less effective treatment management, potentially leading to **treatment failures** and the emergence of **multidrug-resistant TB**.
Question 5: Based on the provided image, which of the following is the correct diagnosis?
- A. Uterus didelphys
- B. Bicornuate Uterus
- C. Unicornuate Uterus (Correct Answer)
- D. Septate uterus
Explanation: ***Unicornuate Uterus*** - The image distinctly shows **only one fallopian tube and one rudimentary uterine horn** on the right side, indicating a unicornuate uterus. - This malformation results from the **incomplete development of one Müllerian duct**, leading to a single, banana-shaped uterine cavity. *Uterus didelphys* - This condition involves **two completely separate uteri**, each with its own cervix and vagina. - The image does not show evidence of two distinct uterine bodies or cervices. *Bicornuate Uterus* - A bicornuate uterus is characterized by **two uterine horns that fuse caudally**, creating a heart-shaped appearance with a shared cervix. - The image clearly lacks the characteristic heart shape and shows only one functional horn. *Septate uterus* - A septate uterus has a **fibrous or muscular septum** dividing the uterine cavity, while the external uterine contour remains normal. - The image does not show a septum or a normal external uterine contour with an internal division; instead, it presents with a single underdeveloped horn.
Question 6: Gold standard investigation for breast carcinoma screening in a patient with silicone breast implants
- A. Mammography
- B. CT scan
- C. USG
- D. MRI (Correct Answer)
Explanation: ***MRI*** - **MRI** is considered the **gold standard** for breast cancer screening in patients with silicone breast implants due to its superior ability to visualize breast tissue through the implant and detect subtle lesions. - It offers **high sensitivity** in detecting both implant rupture and early malignancies, often providing better clarity than mammography in augmented breasts where implants can obscure tissue. *Mammography* - While a standard screening tool, **mammography** can be limited in patients with silicone implants because the implants can **obscure adjacent breast tissue**, making detection of small masses challenging. - Special views (e.g., **Eklund views**) can be used, but sensitivity is still reduced compared to MRI in augmented breasts. *CT scan* - **CT scans** are not routinely used for primary breast cancer screening due to their use of **ionizing radiation** and lower sensitivity for detecting early breast lesions compared to MRI. - CT is more commonly used for **staging** advanced cancers or evaluating complex masses detected by other modalities. *USG* - **Ultrasound (USG)** is a valuable complementary tool, especially for evaluating palpable lumps or clarifying findings from mammography, but it is **operator-dependent** and has a lower overall sensitivity for general screening compared to MRI. - It is particularly useful for differentiating between **cystic and solid masses** and detecting implant ruptures but is not the gold standard for comprehensive screening in augmented breasts.
Question 7: What is the classification of intelligence corresponding to an IQ score of 90-109?
- A. Below average
- B. Average (Correct Answer)
- C. Slightly below average
- D. Above average
Explanation: ***Average*** - An **IQ score** range of **90-109** is traditionally classified as **Average** intelligence. - This range represents the **mean** and surrounding **standard deviation** of IQ scores in the general population. *Below average* - This classification usually corresponds to IQ scores in the range of **70-79** or **80-89**, depending on the specific scale. - It does not represent the central tendency of the population's intelligence. *Slightly below average* - This category typically corresponds to IQ scores in the range of **80-89**. - It falls just below the average range but is not as low as the "below average" classification. *Above average* - This classification is typically assigned to IQ scores that are in the range of **110-119** or higher. - It signifies cognitive abilities that are greater than the majority of the population.
Question 8: Radiation-induced necrosis can be diagnosed by:
- A. MRI
- B. CT
- C. PET
- D. Biopsy (Correct Answer)
Explanation: ***Biopsy*** - A **biopsy** is the definitive diagnostic method for radiation-induced necrosis, allowing for histological examination of tissue to confirm necrosis and rule out residual or recurrent tumor. [1], [2] - It provides a direct view of cellular changes, identifying **necrosis, atypical cells**, and ruling out **malignancy**. *MRI* - While **MRI** can show structural changes indicative of necrosis (e.g., mass effect, edema), it often cannot definitively differentiate between **radiation necrosis** and **tumor recurrence.** [2] - It often shows **T1 hypointensity** and **T2 hyperintensity**, but these findings are not specific. *CT* - **CT scans** are useful for detecting gross changes like **mass effect** and **edema** but have limited sensitivity for distinguishing necrosis from tumor recurrence. - It may show **low-density lesions** but lacks the resolution and specificity for precise diagnosis. *PET* - **PET scans** measure metabolic activity and can help distinguish between **tumor recurrence** (high uptake) and **radiation necrosis** (low uptake) in some cases. - However, false positives can occur, as some inflammatory processes in necrosis can also show increased uptake, making it **less definitive** than a biopsy. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1307-1308. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 340-341.
Question 9: A research team develops an AI algorithm using 100,000 CT scans from multiple institutions. The algorithm shows excellent performance (AUC 0.96) but requires extensive computational resources. To deploy it in resource-limited settings, they propose model compression techniques. Evaluate the potential trade-offs and propose the most balanced approach.
- A. Model compression always maintains performance while reducing size
- B. Use knowledge distillation to train a smaller model that mimics the larger model while accepting minimal performance decrease (Correct Answer)
- C. Avoid compression as any performance loss is unacceptable in medical AI
- D. Random pruning of neural network connections is sufficient
Explanation: ***Use knowledge distillation to train a smaller model that mimics the larger model while accepting minimal performance decrease*** - **Knowledge distillation** allows a "student" model to learn the complex features of a "teacher" model, significantly reducing **computational footprint** while preserving high **diagnostic accuracy**. - This approach is the most balanced for **resource-limited settings**, as it optimizes the trade-off between **model size** and the high **AUC** required for clinical safety. *Model compression always maintains performance while reducing size* - This is incorrect because compression techniques like **quantization** or **pruning** often result in some degree of **information loss** or degradation in metric sensitivity. - The goal of compression is to minimize this loss, but it is not a guaranteed consequence of the process. *Avoid compression as any performance loss is unacceptable in medical AI* - While accuracy is critical, failing to compress the model makes it unusable in **edge devices** or areas with low **processing power**, hindering medical access. - Medical AI deployment requires a pragmatic balance between **idealistic performance** and **practical utility** in real-world clinical environments. *Random pruning of neural network connections is sufficient* - **Random pruning** is suboptimal and lacks the strategic precision needed to maintain the **AUC 0.96** performance level required for radiology. - Effective model optimization requires **structured pruning** or **weight-based selection** to ensure critical diagnostic features are not inadvertently deleted.
Question 10: A radiology department is evaluating two AI algorithms for fracture detection. Algorithm A has AUC-ROC of 0.95, while Algorithm B has AUC-ROC of 0.92 but provides explainable results showing which image regions influenced its decision. Considering clinical implementation and medicolegal aspects, which statement best evaluates the choice?
- A. Algorithm A should always be chosen due to superior performance metrics
- B. Algorithm B may be preferred despite lower AUC due to interpretability and accountability (Correct Answer)
- C. AUC-ROC is the only relevant metric for clinical decision making
- D. The difference in AUC is clinically insignificant so both are equivalent
Explanation: ***Algorithm B may be preferred despite lower AUC due to interpretability and accountability*** - **Explainable AI (XAI)** is critical in medicine because it allows clinicians to verify the **reasoning process**, ensuring the algorithm isn't relying on irrelevant artifacts. - High **interpretability** facilitates **medicolegal accountability** and builds trust, which are often prioritized over marginal gains in statistical performance metrics like **AUC-ROC**. *Algorithm A should always be chosen due to superior performance metrics* - Relying solely on **performance metrics** ignores the "black box" problem, where a model may have high accuracy but fail unexpectedly in **real-world clinical scenarios**. - Without **spatial localization** or explanation, clinicians cannot easily distinguish between a true positive and a **spurious correlation** detected by the AI. *AUC-ROC is the only relevant metric for clinical decision making* - **AUC-ROC** measures general discriminatory power but does not account for **clinical utility**, workflow integration, or the safety implications of **false negatives**. - Other metrics such as **Positive Predictive Value (PPV)** and **Explainability** are equally vital for determining if a tool is safe and effective for bedside use. *The difference in AUC is clinically insignificant so both are equivalent* - A difference between **0.95 and 0.92** can be statistically and clinically significant depending on the **prevalence** of the condition and the volume of images processed. - Labeling them as **equivalent** overlooks the qualitative advantage of **explainability**, which fundamentally changes how the radiologist interacts with the software.
Want unlimited practice?
Get full access to all questions, explanations, and performance tracking.
Start For Free