continuous between the tops of two or more mucosal folds but involves <75% of the circumference.

Grade D is defined as one or more mucosal break that involves ≥75% of the circumference.

Barrett esophagus is a pathologic condition in which the tubular esophagus is lined with columnar

epithelium as opposed to the normal squamous epithelium. It is suspected at endoscopy when there has

been separation of the squamocolumnar junction from the gastroesophageal junction. When columnar

metaplasia is observed, it must be biopsied to confirm the presence of intestinal metaplasia in order to

make the diagnosis of Barrett esophagus; the finding of cardiac metaplasia without goblet cells does not

meet this criteria in the United States. On histologic examination, it appears as columnar mucosa with

goblet cells and is called intestinal metaplasia. Early metaplasia is often manifest as an irregular or

eccentric squamocolumnar junction. Routine four-quadrant biopsies with jumbo forceps are necessary

every 2 cm of columnar metaplasia. In addition, the likelihood of identifying goblet cells is greatest at

the cephalad portion of a columnar segment, especially at the squamocolumnar junction.45 Barrett

esophagus is susceptible to ulceration, bleeding, stricture formation, and malignant degeneration. The

earliest histologic sign of malignant degeneration is high-grade dysplasia (HGD) or intramucosal

adenocarcinoma. These dysplastic changes have a patchy distribution, so a minimum of four biopsy

specimens every 2 cm should be taken from the Barrett mucosa–lined portion of the esophagus. A study

of intramucosal adenocarcinomas arising in Barrett esophagus showed that most of the tumors arose in

the distal Barrett segment, closer to the stomach.46

Abnormalities of the cardia or gastroesophageal junction can be visualized by retroflexion of the

endoscope and provide a complementary assessment regarding the competency of the gastroesophageal

barrier. Hill et al. have graded the appearance of the gastroesophageal valve from I to IV according to

the degree of unfolding or deterioration of the normal architecture (Fig. 42-17).47 This commonly used

grading system has allowed endoscopists to maintain uniformity in their reporting. The Hill grade

correlates well with the competence of the gastroesophageal barrier, with increasing acid exposure

prevalent in patients with worsening Hill grade.

A hiatal hernia is diagnosed by observing separation of the gastroesophageal junction from the crura.

By definition, a hiatal hernia is present when at least 2 cm of the top of the rugal folds has migrated

above the pinch of the diaphragmatic crura. A prominent sliding hiatal hernia is frequently associated

with GERD. When a hernia is observed, particular care is taken to exclude Cameron ulcers or gastritis

within the herniated stomach.

As the endoscope is slowly withdrawn, the esophagus is again examined, and biopsy samples are

taken. The location of the cricopharyngeus is identified, and the larynx and vocal cords are visualized.

Acid reflux may result in inflammation of the larynx. Vocal cord movement should also be recorded,

both as a reference for subsequent surgery and as an assessment of the patient’s ability to protect the

airway.

Esophageal Manometry

Fundamental to the evaluation of a patient with benign esophageal disease is the assessment of

esophageal contractility, coordination, and sphincter function. Manometry is indicated whenever an

abnormality of the esophagus is suggested by the symptoms of dysphagia, odynophagia, chest pain,

heartburn, and regurgitation. It is particularly necessary to confirm the diagnosis of specific primary

esophageal motility disorders, such as achalasia, diffuse esophageal spasm, nutcracker esophagus, or

hypertensive LES. It can also identify ineffective esophageal body motility as a result of GERD or

systemic diseases such as scleroderma, dermatomyositis, polymyositis, or mixed connective tissue

disorders. In patients with symptomatic GERD, esophageal manometry can identify a mechanically

defective LES and evaluate the adequacy of the esophageal body contraction amplitudes and waveform.

Finally, manometry is mandatory for accurate placement of an ambulatory pH monitor in relationship

to the upper border of the LES.

High-resolution manometry (HRM) has now become standard technology over the past several years

and represents an improvement in methodology that leads to a more detailed data collection and

simpler data interpretation, especially with regard to the esophageal body. The concept behind this

technology is that by vastly increasing the number of sensors and reducing the space between the

sensors, it can provide representation of the entire pressure profile along the esophagus from the

pharynx to the proximal stomach without the need to reposition or to pull back the catheter as in

conventional manometry.

The most commonly used HRM system is a solid-state manometric assembly with 36 circumferential

sensors spaced at 1-cm intervals and are available from different manufacturers. These transducers

1052