FMGE 2023 — Radiology

Q: A patient presented to OPD with complaints of fatigue, loss of appetite, constipation, urinary symptoms of kidney stone, and increased urination. The patient has a history of psychiatric disorder; you suspect a case of hyperparathyroidism. Which of the following investigations is useful in this condition?

Sestamibi scan. ***Sestamibi scan*** - This is the standard **nuclear medicine study** used for localizing hyperfunctioning **parathyroid adenomas** prior to surgery (parathyroidectomy), essential for confirming the source of hypercalcemia [1]. - The scan is highly sensitive because the tracer (**Technetium-99m Sestamibi**) is retained longer in the hyperactive parathyroid tissue than in the surrounding thyroid tissue [1]. *USG neck* - **Ultrasonography** is an anatomical study that is often used as a basic initial imaging step due to its non-invasiveness, but it has lower overall sensitivity (50-80%) in localization. - It is poor at locating **ectopic or deep-seated adenomas** and cannot confirm if the lesion is truly hyperfunctioning, which is critical for diagnosis. *CT neck* - **Computed Tomography** is generally reserved for situations where non-invasive methods fail, especially when trying to localize **ectopic glands** deep in the **mediastinum** or neck. - It is not preferred as a first-line investigation due to the associated **radiation exposure** and lack of functional information regarding the glandular activity. *PET scan* - Standard **FDG-PET scans** are mostly ineffective for localizing benign parathyroid adenomas because they rarely exhibit the high metabolic activity required for tracer uptake. - Specialized PET tracers, such as **11C-methionine**, may be used in complicated cases of persistent or recurrent hyperparathyroidism, but are not routine for initial diagnosis. Note: The patient's presentation of kidney stones, psychiatric symptoms, and polyuria is consistent with primary hyperparathyroidism secondary to hypercalcemia [2, 3].

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Q11

A patient presented to OPD with complaints of fatigue, loss of appetite, constipation, urinary symptoms of kidney stone, and increased urination. The patient has a history of psychiatric disorder; you suspect a case of hyperparathyroidism. Which of the following investigations is useful in this condition?