Clinical and Radiological Examination of the Esophagus

Introduction to Clinical Examination of the Esophagus

• Anatomical Location Challenges: The esophagus is situated deep within the neck and thorax before extending into the abdominal cavity. Because of this deep-seated position, direct physical examination is notoriously difficult.

• Direct Visualization: Only the opening of the esophagus can be visualized using conventional methods such as Indirect Laryngoscopy or Direct Laryngoscopy.

• Modern Diagnostic Modalities: Comprehensive evaluation requires advanced modalities including:

  • Barium Meal/Barium Swallow.

  • Endoscopy (Rigid and Flexible).

  • Computed Tomography (CT) Scan.

  • Magnetic Resonance Imaging (MRI) Scan.

  • Positron Emission Tomography (PET) Scan.

  • Oesophageal Manometry.

  • pH-metry.

  • Oesophageal Echocardiography.

Clinical Importance of Neck Examination

• Lymphatic and Metastatic Spread: It is imperative to examine the neck for any masses or lymph nodes. This identifies the potential spread of infection or metastasis of Oesophageal Carcinoma.

• Palpable Esophageal Pathologies: Certain swellings arising from the esophagus, such as a pharyngeal pouch, can be palpated deep to the larynx in the neck.

• Procedural Completeness: A thorough examination of the neck is considered an essential component to finish the clinical assessment of the esophagus.

Oesophagoscopy: Indications and Types

Diagnostic Indications

• Identification of lesions.

• Obtaining biopsy samples in cases of suspected Carcinoma Oesophagus.

• Diagnosing varied esophageal conditions through direct visualization.

Therapeutic Indications

• Removal of foreign bodies.

• Dilation of strictures.

• Placement of endostents for inoperable Carcinoma Oesophagus.

• Injection of sclerosants for the treatment of esophageal varices.

Rigid Oesophagoscopy (Negus type)

• Procedure: Performed under general anesthesia. The patient's head is extended, and the head end of the table is tilted upwards.

• Scope Passage: The scope is passed behind the epiglottis and cricoid through the cricopharyngeal opening. Negotiating the cricopharyngeal opening is the most difficult stage of the procedure; advancement thereafter is generally easier.

• Technical Details:

  • A $25\,cm$ rigid scope is typically adequate for most procedures.

  • A light carrier is inserted into a specialized slot on the side of the oesophagoscope.

Flexible Fibre optic Oesophagoscopy

• Procedure: Can be performed under local anesthesia (LA) and is often done on an Outpatient Department (OPD) basis.

• Strengths: Superior identification of reflux and hiatus hernia. It allows for the visualization of the stomach. It is easier to pass, safer, and less traumatic.

• Drawbacks: Biopsy tissue samples are typically smaller than those obtained by rigid scopes, and the removal of foreign bodies is more difficult.

Comparative Advantages: Rigid vs. Flexible Oesophagoscopy

Strengths of Rigid Oesophagoscopy

• Superior for the removal of foreign bodies.

• Better for examining the upper esophagus.

• Allows for the use of Lasers (Flexible scopes typically do not have this provision unless using the latest advanced equipment).

Strengths of Flexible Oesophagoscopy

• Better for examining the lower esophagus.

• Avoids the immediate need for Barium swallow and CT scan in some diagnostic scenarios.

• Can be performed under Local Anesthesia (Rigid requires GA).

• Can be performed in patients with cervical spine abnormalities or those with thick necks (where rigid scopes are contraindicated).

Surgical Technique for Rigid Oesophagoscopy

• Anatomic Alignment: The proximal esophagus follows the lordosis of the cervical and thoracic spine. These must be brought into a straight line by elevating the head. Note: Prominent osteophytes (e.g., $C6/C7$) may impair advancement.

• Instructional Positioning:

  • Extension increases lordosis and curvature.

  • Flexion reduces lordosis and curvature, making the scope passage easier.

• Manual Protection: The thumb of the non-dominant hand is used as a fulcrum to protect the patient's teeth.

• Advancement: Elevate the tip of the scope against the posterior surface of the cricoid with the non-dominant thumb. Ensure the bevel of the scope points upward.

• Managing Obstruction: The scope reaches a "dead-stop" at the cricopharyngeal sphincter. The clinician must wait for the esophageal lumen to appear while applying steady, firm pressure against the contracted cricopharyngeus muscle.

• Internal Inspection: Once the scope is passed entirely, inspect the mucosa for pathology or trauma while slowly retracting the scope.

Practical Measurements in Oesophagoscopy

Pathology is recorded based on the distance from the upper incisors:

• Cricopharyngeus (Cervical Oesophagus): $15-18\,cm$ from incisors (begins at the level of the $6th$ cervical vertebra/lower edge of cricoid).

• Upper thoracic: $18-23\,cm$ (extends to the thoracic inlet).

• Mid-thoracic: $23-32\,cm$ (at the level of the tracheal bifurcation).

• Lower thoracic (Gastroesophageal junction): $32-40\,cm$.

Complications of Oesophagoscopy

• Mucosal Trauma: Tears and lacerations.

• Esophageal Perforation: A surgical emergency.

  • Most common site of perforation: The level of the cricopharyngeus.

  • Pathophysiology: Rapid leakage of gastric and esophageal contents into the mediastinum leads to mediastinitis, sepsis, and multiorgan failure.

• Clinical Signs of Perforation:

  • Pain in the chest, back, and neck.

  • Odynophagia, dysphagia, tachycardia, tachypnoea, pyrexia, and crepitus.

  • Mackler's Triad: Vomiting, severe chest pain, and subcutaneous emphysema.

  • Hamman's Mediastinal Crunch: A crunching sound heard over the precordium on auscultation during pneumomediastinum.

• Diagnosis of Perforation: Confirmed via Chest X-ray or Gastrografin swallow.

Imaging Modalities: Contrast Studies

Contrast Media Characteristics

• Barium Sulphate ($80\%$ suspension): Superior contrast qualities; preferred unless contraindicated (e.g., suspected perforation).

• Gastrografin: Water-soluble contrast. Used if perforation is suspected but MUST NOT be used if tracheo-oesophageal fistula or aspiration is possible.

• Gastromiro (Iopamidol): Non-ionic water-soluble contrast.

Specific Findings on Barium Swallow

• Achalasia Cardia: Characterized by a "Bird Beak" appearance (dilated esophagus above a narrow cardia). Long-standing cases show a "Sigmoid Oesophagus."

• Diffuse Oesophageal Spasm: Characterized by a "Corkscrew" appearance.

• Esophageal Carcinoma: Characterized by an irregular stenosing lesion with shouldering, known as a "Rat Tail" appearance.

• Pharyngeal Pouch: Visualized as a Zenker's diverticulum, separated from the esophagus by the cricopharyngeal bar.

• External Compression: Indentation of the barium column by mediastinal masses or an enlarged left atrium (as seen in mitral stenosis).

Advanced Imaging and Nuclear Medicine

• Endoscopic Ultrasound (EUS):

  • Modality of choice for T-staging of esophageal cancer (superior to CT).

  • Visualizes the distinct layers of the esophageal wall (alternating hyperechoic and hypoechoic bands).

  • Facilitates Fine Needle Aspiration (FNA) or biopsy of suspicious lymph nodes or growths.

  • Uses Staining: Iodine stains normal cells (containing glycogen) brown; carcinoma cells do not take up iodine and appear pale.

• Computed Tomography (CT): The gold standard for evaluating extraluminal disease and nodal metastasis in carcinoma.

• Magnetic Resonance Imaging (MRI): Utility is limited due to cardiac gating requirements and difficulties with breath-hold sequences, though fast sequences have slightly increased its utility.

• PET-CT: Used for detecting metastasis and the full extent of malignant spread.

• Radionuclide Scans: Primary role is assessing motility disorders and reflux, particularly in children.

• Chest X-ray: Limited role in normal esophageal imaging but can provide clues for perforation (pneumomediastinum), foreign bodies, or achalasia.