313.2 🩺 國考版

313.2.1 高頻考點

313.2.1.1 Anterior Mediastinum — 4 Ts

  • Thymoma (myasthenia gravis 30-40%)
  • Teratoma / germ cell (β-hCG, AFP)
  • Thyroid (substernal goiter)
  • Terrible lymphoma (Hodgkin, DLBCL, PMBCL)

313.2.1.2 Posterior Mediastinum

  • Neurogenic tumors (schwannoma adults, neuroblastoma kids)
  • NF1 association with neurofibromas

313.2.1.3 Middle Mediastinum

  • Lymphadenopathy (sarcoid, lymphoma, infection)
  • Bronchogenic cyst (subcarinal common)
  • Aortic aneurysm

313.2.1.4 Acute Mediastinitis Causes

  • Esophageal rupture (Boerhaave, vomiting; high amylase pleural fluid)
  • Post-cardiac surgery
  • Iatrogenic (endoscopy, biopsy)
  • Penetrating trauma

313.2.1.5 Pneumomediastinum

  • Macklin effect (alveolar rupture)
  • Asthma, vomiting (rule out Boerhaave), mechanical ventilation, drug inhalation
  • Hamman sign
  • Self-limited usually

313.2.1.6 Diaphragm Paralysis

  • Unilateral: phrenic nerve injury (cardiac surgery); often asymptomatic
  • Bilateral: severe respiratory failure, orthopnea
  • Sniff test (paradoxical movement on fluoroscopy)
  • Plication for symptomatic

313.2.1.7 Chest Wall Disorders

  • Pectus excavatum: Haller index > 3.25; Nuss procedure
  • Kyphoscoliosis: restrictive
  • Ankylosing spondylitis: restrictive + upper lobe fibrosis
  • ALS / GBS / MG / muscular dystrophy: NIV for respiratory failure

313.2.1.8 OHS (Obesity Hypoventilation Syndrome)

  • BMI ≥ 30 + PaCO2 > 45 awake
  • NIV + weight loss (bariatric surgery effective)
  • Often OSA + OHS overlap

313.2.1.9 CCHS / Ondine’s Curse

  • PHOX2B mutation
  • Lifelong nocturnal ventilation

313.2.2 易混淆比范

Mass Location Common Mass Workup
Anterior Thymoma, lymphoma, germ cell, thyroid CT + biopsy + markers
Middle LAD, bronchogenic cyst, aortic aneurysm CT + MR + LN biopsy
Posterior Neurogenic, esophageal duplication CT + MRI

313.2.3 Special Topics

313.2.3.1 Thymoma + Paraneoplastic

  • MG (30-40%) — most common
  • Pure red cell aplasia
  • Hypogammaglobulinemia (Good syndrome)
  • SIADH
  • Cushing’s
  • Systemic autoimmune

313.2.3.2 Germ Cell Tumors

  • Seminoma: PLAP, c-kit; RT + cisplatin
  • NSGCT: AFP (yolk sac), β-hCG (choriocarcinoma); chemo cisplatin + BEP

313.2.3.3 Mediastinal Lymphoma vs LAD

  • PET helps distinguish from sarcoid (less FDG avid in sarcoid)
  • Biopsy definitive