Achalasia and diffuse esophageal spasm (DES) are 2 of the more well-known esophageal motility disorders diagnosed on barium studies and manometry. The purpose of this article is to review the spectrum of clinical, radiographic, and manometric findings in patients with achalasia (including primary and secondary achalasia) and DES and to discuss the complementary roles of barium studies and manometry in diagnosing these esophageal motility disorders.
is the Chief of Gastrointestinal Radiology, Department of
Radiology, Hospital of the University of Pennsylvania, and a
Professor of Radiology and an Advisory Dean, University of
Pennsylvania School of Medicine, Philadelphia, PA. He is also on
the editorial board of this journal.
Achalasia and diffuse esophageal spasm (DES) are two of the more
well-known esophageal motility disorders diagnosed on barium
studies and manometry. Classically, achalasia is characterized by
incomplete relaxation of the lower esophageal sphincter (LES) with
absent peristalsis in the body of the esophagus,
whereas DES is characterized by normal relaxation of the LES with
periods of normal peristalsis interspersed with periods of weakened
or absent peristalsis and abnormal simultaneous contractions.
However, some patients with achalasia have complete relaxation of
the LES, whereas others with DES have incomplete relaxation of the
LES, so it is important to be aware of the various permutations of
these esophageal motility disorders. In patients with achalasia, it
is also important to differentiate the primary or idiopathic form
of the disease from a secondary form caused by a malignant tumor
involving the gastroesophageal junction. The purpose of this
article is to review the spectrum of clinical, radiographic, and
manometric findings in patients with achalasia (including primary
and secondary achalasia) and DES and to discuss the relative roles
of barium studies and manometry in diagnosing these esophageal
Primary achalasia is an idiopathic condition in which there is
loss of the ganglion cells in the myenteric plexuses of the
This motility disorder leads to the absence of peristalsis in the
body of the esophagus and incomplete relaxation of the LES.
Primary achalasia usually develops in young or middle-aged
adults <50 years of age.
Achalasia is an insidious disease that progresses slowly over a
period of many years. As a result, affected individuals typically
present with long-standing dysphagia, which has a mean duration of
4 to 5 years at the time of diagnosis.
Most patients are able to maintain their nutritional intake with
little, if any, weight loss.
Less frequently, these individuals may present with chest pain,
regurgitation of undigested food, or recurrent aspiration
Because symptoms are caused by incomplete relaxation of the LES,
these patients usually have a marked clinical response to
procedures for improving LES function, including endoscopic balloon
dilation of the LES, botulinum toxin injections at the
gastroesophageal junction, and, if necessary, laparoscopic or open
Primary achalasia is classically characterized on manometry by
absent peristalsis in the body of the esophagus and incomplete
relaxation of the LES, often accompanied by elevated LES resting
pressures (ie, a hypertensive LES).
However, some patients with achalasia have nonperistaltic
contractions in the esophagus, and others have normal LES function
on manometry. "Vigorous" achalasia, a common variant of achalasia
that is characterized by simultaneous, ineffective, relatively
high-amplitude contractions, has been found to account for as many
as 30% of all cases of achalasia.
The degree of relaxation of the LES on manometry is not a reliable
criterion for diagnosing this condition, as some patients with
typical clinical and radiographic findings of achalasia are found
to have complete relaxation of the LES on manometry.
Therefore, it is important to be aware of the spectrum of
manometric findings in these patients.
Primary achalasia is characterized on barium studies by a
dilated, flaccid esophagus with absent primary peristalsis in the
esophageal body and impaired opening of the LES, causing a smooth,
tapered, beaklike narrowing of the distal esophagus at or directly
adjacent to the gastroesophageal junction (Figure 1).
In patients with vigorous achalasia, barium studies may also reveal
repetitive nonperistaltic contractions in the esophagus, which
manifested as multiple indentations on the barium column that vary
in size and shape at fluoroscopy. Depending on the degree of LES
dysfunction, a standing column of barium typically develops in the
esophagus, with emptying of barium into the stomach only after the
column reaches a critical height. In patients with more
long-standing dysphagia, the esophagus becomes progressively more
dilated (sometimes with considerable retained fluid and debris),
eventually assuming a tortuous or so-called "sigmoid" configuration
(Figures 2 and 3).
Barium studies versus manometry
In various studies, it has been shown that 20% to 30% of
patients with typical features of achalasia on barium studies have
complete relaxation of the LES and, in some cases, normal LES
resting pressures on manometry (Figure 4).
Despite the variable manometric findings, dysphagia in these
individuals usually resolves after endoscopic or surgical treatment
for achalasia. Thus, some patients with achalasia on barium studies
may have no evidence of LES dysfunction on manometry. These
observations raise questions about the role of manometry in
patients with dysphagia and suspected achalasia. If barium studies
reveal typical findings of achalasia, such patients can probably be
treated without need for manometry, avoiding the cost,
inconvenience, and discomfort of this procedure. Nevertheless,
manometry may still be required for patients with clinically
suspected achalasia who have equivocal or negative radiographic
examinations. Therefore, in patients with typical radiographic
findings of achalasia, the barium study can be used to guide
treatment without need for manometry. If the radiographic findings
are equivocal, however, manometry should be performed for a more
Secondary achalasia (also known as pseudoachalasia) is caused by
a malignant tumor at the gastroesophageal junction,
or, less commonly, by benign conditions such as Chagas' disease.
Nearly 75% of patients with secondary achalasia are found to have
an underlying carcinoma of the cardia,
but secondary achalasia may also be caused by carcinoma of the
esophagus or by other malignant tumors that metastasize to the
gastroesophageal junction, including carcinoma of the lung, breast,
pancreas, uterus, ovary, colon, and prostate.
Because secondary achalasia is usually caused by malignant
tumor, affected individuals tend to be older patients (>60 years
of age), with recent onset of dysphagia (<6 months in duration)
and substantial weight loss.
These clinical parameters contrast strikingly with those of primary
achalasia, which tends to occur in younger people with
long-standing dysphagia and little or no weight loss.
Therefore, the clinical presentation is extremely helpful in
differentiating the primary and secondary forms of the disease in
patients with radiographic or manometric findings of achalasia.
Nevertheless, overlap in these clinical parameters has been
In various studies, as many as 28% to 38% of patients with primary
achalasia have been found to be >60 years of age,
so patient age is not an infallible criterion for differentiating
primary from secondary achalasia.
The manometric findings in secondary achalasia may be
indistinguishable from those in primary achalasia. At endoscopy,
however, it is more difficult to advance the endoscope into the
stomach in patients with secondary achalasia than it is in those
with primary achalasia because of tumor circumferentially encasing
the gastroesophageal junction.
This observation, therefore, should increase the endoscopist's
suspicion of secondary achalasia.
In patients with secondary achalasia, barium studies usually
reveal absent primary peristalsis in the body of the esophagus with
tapered, beaklike narrowing of the distal esophagus near the
gastroesophageal junction, mimicking the appearance of primary
achalasia (Figure 5). However, other radiographic findings (such as
eccentricity, nodularity, angulation, straightening, or shouldering
of the narrowed distal segment) should raise concern about the
possibility of secondary achalasia (Figure 6).
Although these classic findings of secondary achalasia are present
in only a small percentage of cases, investigators recently found
that the narrowed distal esophageal segment is >3.5 cm in 80% of
patients with secondary achalasia but rarely exceeds 3.5 cm in
patients with primary achalasia (Figures 6 and 7).
Thus, the length of the narrowed segment appears to be the single
best criterion for differentiating primary achalasia from secondary
achalasia on barium studies. Also, the esophagus tends to be
considerably more dilated in primary achalasia than in secondary
presumably because of the more gradual course of the disease that
allows the esophagus to progressively dilate over a period of
When achalasia is detected on barium studies, it is extremely
important to evaluate the gastric cardia and fundus to rule out
malignant tumor at the gastroesophageal junction as the cause of
these findings. An advanced tumor at the cardia may be manifested
on barium studies by a polypoid or ulcerated mass in this region or
by an infiltrating or scirrhous lesion encasing the gastric fundus
In other patients, barium studies may reveal thickened, lobulated
folds and irregular areas of nodularity or ulceration that distort
or obliterate the normal cardiac rosette,
so optimal double-contrast technique is required to detect these
lesions. Nevertheless, the cardia and fundus cannot be adequately
evaluated on radiographic studies in many patients with secondary
achalasia because of delayed emptying of barium from the esophagus
(so, paradoxically, the stomach empties faster than it fills with
Radiologists, therefore, should be aware of the limitations of
barium studies in evaluating the cardia and fundus in patients with
Computed tomography (CT) may reveal asymmetric thickening of the
distal esophageal wall, a soft tissue mass at the cardia, or
mediastinal adenopathy in patients with secondary achalasia.
In contrast, CT typically reveals little or no esophageal wall
thickening and no evidence of a mass at the cardia in patients with
Therefore, CT may be extremely helpful in differentiating primary
achalasia from secondary achalasia when the clinical or
radiographic findings are equivocal. CT may also be helpful in
identifying the site of the primary tumor or other evidence of
metastatic disease in patients with secondary achalasia caused by
Diffuse esophageal spasm
Some investigators believe that DES is a distinct esophageal
motility disorder characterized by intermittently abnormal
esophageal peristalsis with normal function of the LES. However,
others believe that it may progress over time to the classic form
of achalasia with absent peristalsis in the body of the esophagus
and impaired relaxation of the LES.
It has been postulated that degeneration of the vagal nerve in the
parasympathetic system is the common underlying pathway for the
development of both DES and achalasia.
Patients with DES classically present with chest pain,
dysphagia, or both.
When patients with DES have chest pain because of high-amplitude
esophageal contractions, drugs such as calcium-channel blockers,
long-acting nitrates, and anticholinergics have been shown to
decrease the amplitude of these contractions, sometimes
ameliorating the patient's symptoms.
However, recent work has shown that dysphagia is a more common
finding in patients with DES, at least partly because of the high
frequency of LES dysfunction in these individuals (see discussion
of manometric findings and radiographic findings in this article).
Such patients may experience marked relief of dysphagia from
endoscopic balloon dilatation of the LES or injection of the
botulinum toxin at the gastroesophageal junction.
Diffuse esophageal spasm is characterized on manometry by
intermittently abnormal primary peristalsis associated with a
pattern of repetitive, simultaneous, ineffective contractions of
However, manometric studies have also shown that DES is frequently
associated with LES dysfunction and that more than one third of
these patients have incomplete relaxation of the LES during
Another related condition, vigorous achalasia (see discussion of
achalasia), may closely resemble DES with associated LES
dysfunction on manometry, except that patients with vigorous
achalasia have no episodes of normal peristalsis, whereas patients
with DES have some episodes of normal peristalsis.
In the past, some investigators have even questioned the existence
of vigorous achalasia as a separate disease entity, instead
hypothesizing that achalasia and DES represent opposite ends of a
spectrum of related esophageal motility disorders, with vigorous
achalasia occurring as a transitional phase between DES and
The classic description of DES on barium studies includes the
presence of repetitive, simultaneous, lumen-obliterating
nonperistaltic contractions that compartmentalize the esophagus,
producing a distinctive "corkscrew," "rosary bead," or "shish
kebab" appearance (Figure 8).
In a recent study, however, lumen-obliterating nonperistaltic
contractions were detected on barium studies in <15% of all
patients with DES.
Instead, most patients had nonperistaltic contractions of varying
magnitude that did not obliterate the esophageal lumen (Figure 9).
Thus, radiologists should recognize that the severity of
nonperistaltic contractions can vary in patients with DES and that
the absence of a "corkscrew esophagus" on barium studies in no way
excludes this diagnosis.
Although DES is not traditionally thought to be associated with
LES dysfunction on barium studies,
recent literature suggests that the majority of patients with DES
have impaired LES opening on barium studies with the tapered,
beaklike distal esophageal narrowing that is typically associated
with achalasia (Figure 10).
In a recent study, nearly two thirds of all patients with DES were
found to have impaired LES opening on barium studies.
Thus, it should be recognized that DES is characterized
radiographically by frequent LES dysfunction with nonperistaltic
contractions of varying severity, rather than a classic corkscrew
appearance on barium studies.
Hiatal hernias appear to be more common in patients with DES and
associated LES dysfunction than in those with achalasia (Figure
10). In one study, 89% of patients with DES and impaired opening of
the LES had hiatal hernias on barium studies.
Although hiatal hernias are uncommon in patients with achalasia,
another study found an increased frequency of hiatal hernias in
patients with achalasia who were >50 years of age.
Thus, the higher frequency of hiatal hernias in patients with DES
and LES dysfunction could be related to the older age of these
Barium studies versus manometry
Although there may be discordance between the findings on barium
studies and manometry in the evaluation of DES, most patients with
impaired opening of the LES on barium studies or incomplete
relaxation of the LES on manometry who were treated with endoscopic
balloon dilatation or botulinum toxin injections at the
gastroesophageal junction have had a positive response to therapy.
These data suggest that barium studies and manometry have
complementary roles in the evaluation of patients with DES.
Radiologists and gastroenterologists should be aware of the
radiographic and manometric features of LES dysfunction in patients
with DES, so they can guide proper treatment of these
Barium studies and manometry have complementary roles in the
evaluation of achalasia and DES. Furthermore, these motor
abnormalities should be considered opposite ends of a spectrum of
related esophageal motility disorders, with many patients having
combined radiographic and manometric features of achalasia and