Anatomy clinical correlates: Mediastinum


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Anatomy clinical correlates: Mediastinum

Subspeciality surgery

Cardiothoracic surgery

Valvular heart disease: Clinical (To be retired)

Chest trauma: Clinical (To be retired)

Anatomy clinical correlates: Thoracic wall

Anatomy clinical correlates: Heart

Anatomy clinical correlates: Pleura and lungs

Anatomy clinical correlates: Mediastinum

ENT (Otolaryngology)

Anatomy clinical correlates: Bones, fascia and muscles of the neck

Anatomy clinical correlates: Skull, face and scalp

Anatomy clinical correlates: Trigeminal nerve (CN V)

Anatomy clinical correlates: Facial (CN VII) and vestibulocochlear (CN VIII) nerves

Anatomy clinical correlates: Glossopharyngeal (CN IX), vagus (X), spinal accessory (CN XI) and hypoglossal (CN XII) nerves

Anatomy clinical correlates: Ear

Anatomy clinical correlates: Temporal regions, oral cavity and nose

Anatomy clinical correlates: Vessels, nerves and lymphatics of the neck

Anatomy clinical correlates: Viscera of the neck


Traumatic brain injury: Clinical (To be retired)

Brain tumors: Clinical (To be retired)

Lower back pain: Clinical (To be retired)

Anatomy clinical correlates: Vertebral canal

Anatomy clinical correlates: Spinal cord pathways

Anatomy clinical correlates: Cerebral hemispheres

Anatomy clinical correlates: Anterior blood supply to the brain

Anatomy clinical correlates: Cerebellum and brainstem


Eye conditions: Refractive errors, lens disorders and glaucoma: Pathology review

Eye conditions: Retinal disorders: Pathology review

Eye conditions: Inflammation, infections and trauma: Pathology review

Anatomy clinical correlates: Olfactory (CN I) and optic (CN II) nerves

Anatomy clinical correlates: Oculomotor (CN III), trochlear (CN IV) and abducens (CN VI) nerves

Anatomy clinical correlates: Eye

Orthopedic surgery

Anatomy clinical correlates: Clavicle and shoulder

Anatomy clinical correlates: Axilla

Anatomy clinical correlates: Arm, elbow and forearm

Anatomy clinical correlates: Wrist and hand

Anatomy clinical correlates: Median, ulnar and radial nerves

Anatomy clinical correlates: Bones, joints and muscles of the back

Anatomy clinical correlates: Hip, gluteal region and thigh

Anatomy clinical correlates: Knee

Anatomy clinical correlates: Leg and ankle

Anatomy clinical correlates: Foot

Plastic surgery

Burns: Clinical (To be retired)


Penile conditions: Pathology review

Prostate disorders and cancer: Pathology review

Testicular tumors: Pathology review

Kidney stones: Clinical (To be retired)

Renal cysts and cancer: Clinical (To be retired)

Urinary incontinence: Pathology review

Testicular and scrotal conditions: Pathology review

Anatomy clinical correlates: Male pelvis and perineum

Anatomy clinical correlates: Other abdominal organs

Androgens and antiandrogens

PDE5 inhibitors

Adrenergic antagonists: Alpha blockers

Vascular surgery

Peripheral vascular disease: Clinical (To be retired)

Leg ulcers: Clinical (To be retired)

Aortic aneurysms and dissections: Clinical (To be retired)


Anatomy clinical correlates: Mediastinum

USMLE® Step 1 questions

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USMLE® Step 2 questions

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USMLE® Step 1 style questions USMLE

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USMLE® Step 2 style questions USMLE

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A 55-year-old man presents for follow-up evaluation after a recent myocardial infarction. The patient had a high-grade occlusion of the left anterior descending artery with stent placement. The patient has been compliant with medications. However, he has pain and weakness in the left upper extremity with exercise. The patient states, “I know something is not right. My arm turns ghost white every time I get on the treadmill, and I feel like I will pass out.” Past medical history includes hypertension, diabetes, and hyperlipidemia. Medications include aspirin, carvedilol, amlodipine, metformin, atorvastatin, and clopidogrel. He has a twenty-pack-year smoking history. Temperature is 37.0°C (98.6°F), pulse is 62/min, respirations are 14/min, and blood pressure is 140/70 mmHg in the right arm compared with 121/65 mmHg in the left arm. The left radial pulse demonstrates arrival delay compared to the right radial pulse. The patient's left hand presents a brisk capillary refill. The patient’s cardiologist subsequently orders an ultrasound of the heart and upper extremities. Which of the following findings is most likely to be found on ultrasonographic evaluation?  



Anca-Elena Stefan, MD

Evan Debevec-McKenney

Ursula Florjanczyk, MScBMC

We all know how important the heart is, but everyone forgets about the mediastinum, which is the area between the two lungs where the heart actually sits!

The mediastinum doesn't just house the heart, but many important structures in the thoracic cavity from the superior thoracic aperture down to the diaphragm.

So let's take a closer look at the clinical conditions that can affect the mediastinum and the structures within it.

First up, there is widening of the mediastinum, which can be seen on a chest x-ray.

Since the mediastinum contains so many structures, each of them can contribute to pathological widening.

It can be observed after a trauma that causes laceration or dissection of the great-vessels, typically the aorta, which can cause hemorrhaging into the mediastinum.

Other times, malignant tumors such as lymphomas can produce massive enlargement of mediastinal lymph nodes and widening of the mediastinum.

Another cause of mediastinal widening is heart hypertrophy due to congestive heart failure.

Now, next up, there’s the esophagus.

The esophagus may have up to four normal anatomic constrictions as it descends, however there are three sites of constriction that can occur specifically in the posterior mediastinum caused by three structures it meets on its way down: two thoracic constrictions with the first being where the esophagus is crossed by the arch of the aorta, and second where it is crossed by the left main bronchus, and one diaphragmatic constriction where it passes through the esophageal hiatus of the diaphragm.

The fourth site of constriction occurs in the cervical region before the esophagus enters the mediastinum, where constriction may be caused by the cricopharyngeus muscle.

At these locations, there’s a slower passage of substances and is where foreign objects that are swallowed are most likely to lodge.

These narrowings can be seen in chest radiographs of a person who underwent a barium swallow study.

These areas are also at risk of stricture after ingesting caustic liquids such as cleaning products.


  1. "Comprehensive Cytopathology E-Book: Expert Consult: Online and Print" Saunders (2007)
  2. "Gray's Anatomy for Students" Churchill Livingstone (2004)
  3. "The Epiaortic Ultrasound Diagnosis of Iatrogenic Subadventitial Hematoma" A&A Practice (2020)
  4. "An unexpected finding late after repair of coarctation of the aorta" Netherlands Heart Journal (2008)
  5. "Management of acute aortic dissection" The Lancet (2015)
  6. "Risk Factors for Aneurysm Rupture in Patients Kept Under Ultrasound Surveillance" Annals of Surgery (1999)
  7. "Prevalence and Impact of the Subclavian Steal Syndrome" Annals of Surgery (2010)

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