What endoscopic findings are characteristic of Barrett's esophagus?

Endoscopic Findings in Barrett's Esophagus

On endoscopy, Barrett's esophagus is diagnosed by visualizing salmon-pink or reddish columnar epithelium extending at least 1 cm above the gastroesophageal junction, replacing the normal pale squamous lining of the distal esophagus. 1

Key Endoscopic Features

Primary Diagnostic Criterion

• Columnar epithelium must be clearly visible endoscopically (≥1 cm) above the gastroesophageal junction (GOJ), measured using the Prague C&M classification system 1
• The columnar-lined segment appears as salmon-pink or reddish mucosa, distinctly different from the pale, glossy squamous epithelium 2, 3

Identifying the Gastroesophageal Junction

The GOJ must be accurately identified to diagnose Barrett's esophagus. The proximal limit of the longitudinal gastric folds with minimal air insufflation is the easiest and most reliable landmark 1:

• Gastric folds have a reliability coefficient of 0.88 for identifying the GOJ 1
• The distal end of palisade vessels can also mark the GOJ, but this has poor reproducibility (κ = 0.14) 1

Prague C&M Classification (Required Documentation)

All Barrett's esophagus findings must be documented using the Prague classification 1:

• C (Circumferential extent): Length in centimeters of circumferential columnar lining above the GOJ
• M (Maximum extent): Maximum length in centimeters of any tongues of columnar epithelium extending above the GOJ
• Example notation: C3M5 indicates 3 cm of circumferential Barrett's with tongues extending to 5 cm
• This system has a reliability coefficient of 0.72 for Barrett's ≥1 cm 1

Distinguishing from Irregular Z-Line

Barrett's esophagus should NOT be diagnosed if only an irregular Z-line is present 1:

• Irregular Z-line shows tongues of columnar epithelium <1 cm with no confluent segment 1
• The 1 cm minimum threshold is critical—anything less should not receive a Barrett's diagnosis 1
• If uncertain whether findings represent irregular Z-line versus Barrett's, do not make the diagnosis 1

Associated Endoscopic Findings

Common Complications Visible at Endoscopy

Barrett's esophagus frequently presents with complications 4:

• Reflux esophagitis (56% of cases) at the squamocolumnar junction 4
• Stricture formation (38%) at the squamocolumnar junction or within columnar epithelium 4
• Ulceration (36%) within the Barrett's segment 4
• Hiatal hernia present in the majority of cases 4

Visible Lesions Requiring Documentation

Any visible mucosal abnormalities must be recorded 1:

• Document number and distance from incisors
• Classify using Paris classification: 0-Ip (pedunculated), 0-Is (sessile), 0-IIa (elevated), 0-IIb (flat), 0-IIc (depressed), 0-III (excavated) 1
• Targeted biopsies of visible lesions should be taken BEFORE random biopsies to avoid obscuring the view with bleeding 1

Advanced Imaging Techniques (Not Routinely Required)

Image-Enhanced Endoscopy

While standard white-light endoscopy remains the gold standard, several adjunctive techniques exist 1:

• Methylene blue chromoendoscopy: Selectively stains intestinal metaplasia blue while squamous and gastric mucosa remain pale, but there is insufficient evidence to support routine use 1
• Narrow-band imaging (NBI): Enhances visualization of surface glandular structures and vascular patterns, but remains investigational 1
• These techniques may improve dysplasia detection but are operator-dependent and not standard practice 1

Critical Pitfalls to Avoid

• Inadequate air insufflation can cause gastric folds to extend into the esophagus, leading to underestimation of Barrett's length 1
• Excessive insufflation can flatten gastric folds and obscure the GOJ 1
• Confusing irregular Z-line with Barrett's esophagus—if columnar epithelium is <1 cm, do not diagnose Barrett's 1
• Failing to document Prague classification—this is essential for surveillance planning and risk stratification 1

Histologic Confirmation Required

Endoscopic appearance alone is insufficient—diagnosis requires histologic confirmation of columnar metaplasia from esophageal biopsies 1:

• The British Society of Gastroenterology requires intestinal metaplasia for definitive diagnosis 1
• The American Gastroenterological Association accepts either intestinal-type or cardia-type epithelium, though only intestinal metaplasia has established cancer risk 1
• Seattle biopsy protocol (four-quadrant biopsies every 2 cm plus targeted biopsies) should be performed 1