A 48-year-old female complains of tingling sensation in her fingertips as well as the skin around her mouth which woke her up from sleep. She is in the postoperative floor as she just underwent a complete thyroidectomy for papillary thyroid cancer. Her temperature is 37° C (98.6° F), respirations are 15/min, pulse is 67/min, and blood pressure is 122/88 mm Hg. While recording the blood pressure, spasm of the muscles of the hand and forearm is seen. What is the next best step in the management of this patient?

No treatment is necessary, this is expected following surgery

A 55-year-old man presents to the physician with tiredness, lethargy, bone pain, and colicky right abdominal pain for 1 month. He has no comorbidities. He does not have any significant past medical history. His height is 176 cm (5 ft 7 in), weight is 88 kg (194 lb), and his BMI is 28.47 kg/m2. The physical examination is normal, except for mild right lumbar region tenderness. Laboratory studies show: Hemoglobin 13.5 g/dL Serum TSH 2.2 mU/L Serum calcium 12.3 mg/dL Serum phosphorus 1.1 mg/dL Serum sodium 136 mEq/L Serum potassium 3.5 mEq/L Serum creatinine 1.1 mg/dL Urine calcium Elevated An ultrasound of the abdomen reveals a single stone in the right ureter without hydroureteronephrosis. Clinically, no evidence of malignancy was observed. An X-ray of the long bones reveals diffuse osteopenia with subperiosteal bone resorption. The serum parathyroid hormone level is tested and it is grossly elevated. What is the most appropriate next step in his management?

99mTc sestamibi scan with ultrasound of the neck

A 68-year-old man comes to the physician because of a 6-month history of difficulty swallowing pieces of meat and choking frequently during meal times. He also sometimes regurgitates foul-smelling, undigested food particles. Examination shows a 3 x 3 cm soft cystic, immobile mass in the upper third of the left side of his neck anterior to the left sternocleidomastoid muscle that becomes prominent when he coughs. A barium swallow shows an accumulation of contrast on the lateral aspect of the neck at the C5 level. Which of the following is the most likely underlying cause for this patient's condition?

Increased intrapharyngeal pressure

Remnant of the embryological omphalomesenteric duct

Inadequate relaxation of lower esophageal sphincter

Remnant of the thyroglossal duct

Remnant of the second branchial cleft

A 67-year-old woman with tertiary hyperparathyroidism and end-stage renal disease on hemodialysis has persistent hypercalcemia (calcium 12.8 mg/dL) despite maximal medical management with cinacalcet and vitamin D restriction. She has severe pruritus, calciphylaxis, and vascular calcifications. All four parathyroid glands are enlarged on imaging. Evaluate the optimal surgical strategy considering her complex medical status and need for ongoing dialysis access.

Total parathyroidectomy with forearm autotransplantation

Single adenoma resection guided by sestamibi

Subtotal parathyroidectomy (3.5 gland resection)

Total parathyroidectomy without autotransplantation

Medical management escalation with denosumab

A 30-year-old man presents with a 6 cm adrenal mass discovered incidentally. Biochemical workup shows elevated 24-hour urine metanephrines and plasma free metanephrines. He also has elevated serum calcium, PTH, and a pancreatic head mass on CT. Genetic testing confirms MEN 2B syndrome. Evaluate the management priorities and sequencing of interventions.

Adrenalectomy first, then thyroidectomy, then other tumors

Simultaneous thyroidectomy and bilateral adrenalectomy

Medical management of pheochromocytoma then parathyroidectomy

Immediate thyroidectomy followed by staged procedures

Pancreatic surgery first due to mass effect

A 38-year-old woman with primary hyperparathyroidism (calcium 11.8 mg/dL, PTH 185 pg/mL) has negative sestamibi scan and ultrasound. She desires surgical cure and has no medical contraindications. She has a Z-score of -2.8 on DEXA scan and a history of recurrent kidney stones. Evaluate the surgical approach and expected outcomes.

Bilateral neck exploration with identification of all four glands

Defer surgery until localization studies are positive

Minimally invasive parathyroidectomy of the largest gland

Medical management with cinacalcet and bisphosphonates

Intraoperative PTH-guided focused exploration

Radioguided parathyroidectomy for USMLE Step 3: High-Yield Surgery Lessons

☢️ Gland Hunt Guidance

Radiotracer: Technetium-99m ($^{99m}$Tc) Sestamibi is injected pre-op, localizing the adenoma.
Mechanism: Concentrates in mitochondria-rich, hyperfunctioning parathyroid tissue. Thyroid uptake washes out faster than parathyroid uptake.
Intra-op Tool: A handheld gamma probe detects gamma radiation, guiding the surgeon to the "hot" gland.
Goal: Facilitates minimally invasive parathyroidectomy (MIP) by avoiding extensive neck exploration, especially for ectopic glands.

⭐ Successful excision is confirmed by a >50% drop in intraoperative PTH (ioPTH) from baseline 10 minutes post-excision (Miami criterion).

💎 Anatomy - Neck's Hidden Gems

Glands: Typically 4 pea-sized glands on the posterior thyroid surface.
- Superior (x2): More constant. Located posterior to the Recurrent Laryngeal Nerve (RLN), near the cricothyroid junction.
- Inferior (x2): More variable. Located anterior to the RLN, often near the lower thyroid pole.
Blood Supply: Primarily from branches of the Inferior Thyroid Artery (ITA).
Ectopic Locations: Thymus, mediastinum, carotid sheath, retroesophageal space.
Nerve at Risk: RLN runs in the tracheoesophageal groove.

⭐ The inferior parathyroids (and thymus) arise from the 3rd pharyngeal pouch, explaining their variable descent. The superior glands (and thyroid C-cells) arise from the 4th pouch.

Parathyroid glands, thyroid, and recurrent laryngeal nerve

☢️ Radiology - Tag, Track, Target

This technique enables minimally invasive parathyroidectomy (MIP) by precisely locating the adenoma.

Radiotracer: Technetium-99m ($^{99m}$Tc) Sestamibi is injected preoperatively. It is preferentially retained by hyperfunctioning parathyroid tissue (adenomas/hyperplasia).
Gamma Probe: A handheld device used intraoperatively to detect gamma radiation from the tagged adenoma, guiding a focused, minimally invasive excision.
Intraoperative PTH (ioPTH): Essential biochemical confirmation of successful removal.

⭐ Miami Criterion: A >50% drop in intraoperative PTH (ioPTH) from the highest pre-excision baseline, measured 10 minutes after gland removal, indicates a high likelihood of surgical cure.

Sestamibi scan showing parathyroid adenoma uptake

🎯 Management - The Surgical Snipe

Radioguided surgery localizes a pre-operatively identified adenoma for minimally invasive parathyroidectomy (MIP).

Radiotracer: Technetium-99m ($^{99m}$Tc) Sestamibi is injected pre-op.
- It concentrates in mitochondria-rich oxyphil cells of the adenoma.
Tool: A handheld gamma probe detects radioactivity intraoperatively, guiding the surgeon to the "hot" gland.
Goal: Smaller incision, focused dissection, reduced operative time.

⭐ Miami Criterion: A >50% drop in intraoperative PTH (ioPTH) from the highest pre-excision level, 10 minutes after gland removal, confirms successful resection.

⚠️ Complications - Post-Op Pitfalls

Hypocalcemia: Most common pitfall.
- Due to parathyroid stunning, devascularization, or inadvertent removal.
- "Hungry Bone Syndrome": Severe, prolonged ↓Ca²⁺ in patients with severe pre-op bone disease.
- Presents with perioral numbness, Chvostek/Trousseau signs.
Recurrent Laryngeal Nerve (RLN) Injury: Unilateral → hoarseness; Bilateral → stridor/airway compromise.
Neck Hematoma: Can cause acute airway compression.

⭐ Persistent hyperparathyroidism is defined as elevated calcium and PTH levels within 6 months post-op, indicating surgical failure (e.g., missed adenoma, multiglandular disease).

⚡ Biggest Takeaways

Primary use: Locating a solitary parathyroid adenoma for minimally invasive parathyroidectomy (MIP).

Radiotracer: Technetium-99m sestamibi concentrates in hyperactive parathyroid tissue before surgery.

Intraoperative guidance: A handheld gamma probe detects radioactivity, pinpointing the adenoma.

Success confirmation: A >50% drop in intraoperative PTH (ioPTH) at 10 minutes post-excision.

Key benefit: Enables focused surgery, avoiding routine four-gland exploration and reducing morbidity.

Limitation: Not ideal for multi-gland disease or parathyroid hyperplasia.

Continue reading on Oncourse

CONTINUE READING — FREE

or get the app

App Store|Google Play