DOI:10.2214/AJR.07.3747
AJR 2008; 191:758-763
© American Roentgen Ray Society
Diffuse Esophageal Spasm: CT Findings in Seven Patients
Michael F. Goldberg1,
Marc S. Levine and
Drew A. Torigian
1 All authors: Department of Radiology, Hospital of the University of
Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104.
Received January 29, 2008;
accepted after revision March 22, 2008.
M. S. Levine is a consultant for E-Z-EM.
Address correspondence to M. S. Levine
(marc.levine{at}uphs.upenn.edu).
Abstract
OBJECTIVE. The purpose of this study was to determine the frequency
and appearance of esophageal wall thickening on CT scans in a series of
patients with findings of diffuse esophageal spasm on barium studies.
CONCLUSION. CT revealed marked esophageal wall thickening in seven
(21%) of 33 patients who had findings of diffuse esophageal spasm on barium
studies. CT showed significantly greater esophageal wall thickening in the
lower thoracic esophagus 5 cm above the gastroesophageal junction than in the
upper thoracic esophagus at the level of the aortic arch or in the midthoracic
esophagus at the level of the carina (p < 0.01). This esophageal
wall thickening corresponded to the presence of multiple strong nonperistaltic
contractions in the lower thoracic esophagus on barium studies. Our findings
suggest that diffuse esophageal spasm should be included in the differential
diagnosis when CT shows smooth circumferential wall thickening in the lower
half of the thoracic esophagus, particularly in elderly patients with
dysphagia or chest pain.
Keywords: barium study • CT • diffuse esophageal spasm • esophageal cancer • esophageal motility disorder
Introduction
Diffuse esophageal spasm (DES) is an uncommon primary motility disorder of
the esophagus that causes chest pain and dysphagia, primarily in elderly
persons [1,
2]. The diagnosis can be
established with manometric evidence of intermittently abnormal primary
esophageal peristalsis associated with a pattern of repetitive simultaneous
ineffective contractions of varying amplitude
[1,
2]. DES also can be diagnosed
when a barium study shows intermittent weakening or absence of primary
peristalsis interspersed with numerous nonperistaltic contractions of varying
severity and frequent dysfunction of the lower esophageal sphincter (LES)
[3].
We encountered a patient in whom CT revealed marked esophageal wall
thickening worrisome for esophageal cancer, but a subsequent barium study
revealed DES as the cause of this finding. To our knowledge, the radiologic
literature contains only one report
[4] of a similar situation, in
which CT of three patients with DES revealed smooth circumferential esophageal
wall thickening. The purpose of our investigation was to determine the
frequency and appearance of esophageal wall thickening on CT in a series of
patients in whom DES had been found on barium studies.
Materials and Methods
Patient Population
A computerized search of the radiology database at our university hospital
by one author revealed 113 patients with a diagnosis of DES on barium studies
during the 9-year period January 1998 through December 2006. As describ ed in
the literature [3], DES is
characterized radiographically by intermittently weakened or absent primary
esophageal peristalsis and multiple simultaneous nonperistaltic contrac tions
of varying severity with or without LES dysfunction. Thirty-three (29%) of the
113 patients also underwent CT of the chest within 1 month of the barium
study. The mean interval between CT and barium study was 9 days (range,
1–21 days). Subsequent review of the CT scans by one author revealed
that seven (21%) of the 33 patients had esophageal wall thickening, defined as
an esoph ageal wall thickness of more than 3 mm
[5]. Esophageal wall thickness
was assessed at each of three levels: the aortic arch, the carina, and 5 cm
above the gastroesophageal junction. The seven patients constituted our study
group. Our insti tutional review board approved all aspects of this
retrospective study and did not require informed consent for patients whose
records were included. A HIPAA waiver was obtained before the study was
initiated.
Medical records were reviewed to determine the clinical presentations of
the seven patients and the indications for CT. Three (43%) of the seven
patients underwent esophageal manometry within 1 month of barium study (mean
interval, 10 days; range, 2–23 days). In two of these three patients,
manometry revealed multiple simultaneous esophageal contractions and a
hypertensive LES compatible with DES and associated LES dysfunction. In the
third patient, manometry revealed poor primary peristalsis without evidence of
simultaneous esophageal contractions.
Examination Technique
Barium study—All seven patients underwent biphasic
esophagography that included upright double-contrast views obtained with an
effervescent agent (Baros, Lafayette Pharmaceuticals) and a 250% weight/volume
barium suspension (E-Z-HD, E-Z-EM) and prone single-contrast views obtained
with a 50% weight/volume barium suspension (Entrobar, Mallinckrodt Imaging).
For all studies, patients were asked to take multiple discrete swallows in the
prone right anterior oblique position for evaluation of esophageal motility.
The studies were performed by residents, fellows, or one of three attending
gastrointesti nal radiologists. All of the studies were interpreted by the
attending radiologists.
CT—All seven patients underwent helical CT of the chest
(HiSpeed Advantage or HiSpeed CT/iscanner, GE Healthcare) according to an
established protocol. All seven patients received 100 mL of 60% iodinated
contrast material (diatrizoate meglumine, Hypaque, GE Healthcare; iohexol,
Omnipaque 300, GE Healthcare) IV, and one patient received 500 mL of
2–3% oral contrast material (diatrizoate meglumine and diatrizoate
sodium solution, Gastrografin, Bracco Diagnostics) before the study. CT images
were routinely obtained with the patient in the supine position during full
inspiration. Axial images were obtained with a slice thickness of 5 or 7 mm
and were reconstructed with a soft-tissue algorithm.
Review of Images
Although videotapes of swallowing studies are not stored by our department
on a long-term basis, the original radiographic reports from these seven
barium studies provided a relatively detailed assessment of esophageal
motility. In all cases, the reports were used to determine whether primary
peristalsis was intermittently weakened or absent. Weakened peristalsis was
defined as delayed propagation or variable disruption of the peristaltic
stripping wave as it traversed the esophagus, often associated with incomplete
clearance of barium from the esophagus when the peristaltic wave reached the
gastroesophageal junction. In contrast, absent peristalsis was defined as
complete absence of the peristaltic stripping wave in the esophagus. Motility
was considered abnormal if an abnormal peristaltic wave or esophageal
aperistalsis was found at fluoroscopy on two or more of five separate swallows
of barium in the prone right anterior oblique position, as described by Ott et
al. [6].
The reports and images from the seven barium studies were reviewed to
determine the strength, frequency, and location of nonperistaltic
contractions, which were classified as occasional or numerous and as mild,
moderate, or marked (i.e., lumen obliterating or nearly lumen obliterating) in
severity. We also looked for tapered beaklike narrowing of the distal
esophagus, a radiographic sign of impaired LES opening in patients with DES
[7]. Finally, the images were
reviewed to determine whether any of the patients had a hiatal hernia.
The chest CT scans of the seven patients were reviewed retrospectively at a
PACS workstation (Centricity, GE Healthcare) by consensus of all three
authors. The workstation enabled interpretation and scrolling of CT images in
the axial plane. The scans were reviewed to determine the maximal esophageal
wall thickness at three levels in the esophagus: the aortic arch, the carina,
and 5 cm above the gastroesophageal junction. Eso phageal wall thickening was
characterized as smooth versus nodular and as circumferential versus
asymmetric. Luminal diameter was measured at each of the three levels. Other
relevant abnormalities, such as presence or absence of a mediastinal mass or
increased periesophageal fat, were documented.
Spreadsheet software (Excel, Microsoft) was used to analyze the data with a
paired Student's t test to determine the presence of significant
differences in mean esophageal wall thicknesses on CT at the levels of the
aortic arch, carina, and 5 cm above the gastroesophageal junction in the seven
patients with DES.
Results
Clinical Findings
Five (71%) of the seven patients were men, and two (29%) were women. The
mean age was 73 years (range, 55–93 years). Five patients had dysphagia,
but none had chest pain. The indications for CT included abnormalities on
chest radiographs in four (57%) of the patients (recurrent infiltrates in two,
mediastinal mass in one, possible lung nodule in one); evaluation of possible
extrinsic masses involving the gastroesophageal junction in two (29%) of the
patients; and staging of colon cancer in one (14%) of the patients. Among the
four patients with abnormalities on chest radiographs, CT showed evidence of
aspiration pneumonia in two patients, substernal goiter in one patient, and no
evidence of a lung nodule in one patient. In the two patients with
questionable masses involving the gastroesophageal junction, CT showed no
evidence of extrinsic lesions in this region. Finally, in the patient with
colon cancer, CT showed no evidence of metastatic disease in the chest.
Radiographic Findings
Barium study—Barium studies revealed findings of DES with
intermittently abnormal motility characterized by weakened peristalsis in one
(14%) of the patients, lack of peristalsis in four (57%), and weakened
peristalsis on some swallows and lack of peristalsis on others in two (29%) of
the patients. All patients had associated nonperistaltic contractions; the
contractions were numerous in six (86%) and occasional in one (14%) of these
patients, and they were marked (nearly lumen-obliterating) in two (29%) (Figs.
1A and
2A), moderate in three (43%)
(Fig. 3A), and mild in two
(29%) of these patients. In all seven patients, these nonperistaltic
esophageal contractions were found in the lower thoracic esophagus below the
level of the carina. All seven patients also had variable beaklike narrowing
of the distal esophagus at or adjacent to the gastroesophageal junction caused
by impaired opening of the LES (Figs.
1A,
2A, and
3A). Five (71%) of the seven
patients had hiatal hernias.
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Fig. 1A —55-year-old man with diffuse esophageal spasm and dysphagia.
Single-contrast prone right anterior oblique esophagram shows diffuse
esophageal spasm with marked (nearly lumen-obliterating) nonperistaltic
contractions (white arrows) and narrowing of distal esophagus
(small black arrow) due to incomplete opening of lower esophageal
sphincter. Large black arrow denotes small hiatal hernia.
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Fig. 2A —60-year-old man with diffuse esophageal spasm and dysphagia.
Single-contrast prone right anterior oblique esophagram shows diffuse
esophageal spasm with marked nonperistaltic contractions (black
arrows) and short segment of tapered narrowing in distal esophagus
(small white arrow) due to incomplete opening of lower esophageal
sphincter. Large white arrow denotes small hiatal hernia.
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Fig. 3A —72-year-old man with diffuse esophageal spasm but no
dysphagia who was only patient in study with asymmetric wall thickening of
lower thoracic esophagus. Single-contrast prone right anterior oblique
esophagram shows diffuse esophageal spasm with moderate nonperistaltic
contractions (black arrows) and tapered narrowing of distal esophagus
(small white arrow) due to incomplete opening of lower esophageal
sphincter. Large white arrow denotes small hiatal hernia.
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CT—CT revealed esophageal wall thickening in seven (21%) of
33 patients with evidence of DES on barium studies (Figs.
1B,
1C,
1D,
2B,
2C,
2D, and
3B,
3C,
3D)
(Table 1). In these patients,
the mean maximal esophageal wall thickness at the level of the aortic arch was
5 mm (range, 2–7 mm); carina, 7 mm (range, 4–13 mm); and 5 cm
above the gastroesophageal junction, 11.9 mm (range, 5–15 mm). On CT,
the mean thickness of the esophageal wall therefore was significantly greater
in the lower thoracic esophagus 5 cm above the gastroesophageal junction (11.9
mm) than in the upper thoracic esophagus at the level of the aortic arch (5
mm) and in the midthoracic esophagus at the level of the carina (7 mm)
(p < 0.01). With these measurements, esophageal wall thickening
was detected in five (71%) of the patients at the level of the aortic arch and
in all seven patients at the levels of the carina and 5 cm above the
gastroesophageal junction. The mean luminal diameters at the three levels were
21 mm (range, 10–58 mm), 19.1 mm (range, 5–39 mm), and 10.9 mm
(range, 0–34 mm) (Table
1).
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Fig. 1B —55-year-old man with diffuse esophageal spasm and dysphagia.
Contrast-enhanced axial CT scan at level of aortic arch shows moderate smooth
symmetric thickening (arrow) of esophageal wall. Mediastinal goiter
with mass effect on trachea and esophagus is partially depicted.
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Fig. 1D —55-year-old man with diffuse esophageal spasm and dysphagia.
Axial CT scan 5 cm above gastroesophageal junction shows greatest degree of
esophageal wall thickening (arrow) at this level, although thickened
wall is still smooth and symmetric.
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Fig. 2B —60-year-old man with diffuse esophageal spasm and dysphagia.
Unenhanced axial CT scan near level of aortic arch shows moderate smooth
symmetric thickening (arrow) of esophageal wall at this level.
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Fig. 2D —60-year-old man with diffuse esophageal spasm and dysphagia.
Axial CT scan 5 cm above gastroesophageal junction shows greatest degree of
esophageal wall thickening (arrow) at this level, although thickened
wall is still smooth and symmetric. As shown in Figures
1A,
1B,
1C,
1D and
2A,
2B,
2C, 2D, a relatively long
segment of smooth, circumferential wall thickening in lower half of thoracic
esophagus is characteristic of diffuse esophageal spasm on CT.
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Fig. 3B —72-year-old man with diffuse esophageal spasm but no
dysphagia who was only patient in study with asymmetric wall thickening of
lower thoracic esophagus. Contrast-enhanced axial CT scan near level of aortic
arch shows moderate smooth symmetric thickening (arrow) of esophageal
wall at this level.
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Fig. 3C —72-year-old man with diffuse esophageal spasm but no
dysphagia who was only patient in study with asymmetric wall thickening of
lower thoracic esophagus. Axial CT scan at level of carina shows nodular
asymmetric esophageal wall thickening (arrow) at this level.
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Fig. 3D —72-year-old man with diffuse esophageal spasm but no
dysphagia who was only patient in study with asymmetric wall thickening of
lower thoracic esophagus. Axial CT scan 5 cm above gastroesophageal junction
shows greatest degree of esophageal wall thickening (arrow) at this
level with considerable nodularity and asymmetry of thickened wall.
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TABLE 1: Esophageal Wall Thickness (mm) and Luminal Diameter (mm) on CT in Seven
Patients with Diffuse Esophageal Spasm
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Five (71%) of the patients had CT evidence of smooth wall thickening, and
two (29%) had nodular thickening at the level of the aortic arch; six (86%)
had smooth thickening, and one (14%) had nodular thickening at the level of
the carina; and six (86%) had smooth thickening, and one (14%) had nodular
thickening 5 cm above the gastroesophageal junction (Figs.
1A,
1B,
1C,
1D,
2A,
2B,
2C,
2D,
3A,
3B,
3C,
3D). Five patients had CT
evidence of circumferential wall thickening, and two had asymmetric thickening
at the level of the aortic arch; six patients had circumferential thickening,
and one had asymmetric thickening at the level of the carina; and six had
circumferential thickening, and one had asymmetric thickening 5 cm above the
gastroesophageal junction. Six of the seven patients with CT evidence of a
thickened esophageal wall therefore had smooth circumferential esophageal wall
thickening that was most marked over a long segment of the esophagus extending
distally from the carina to the gastroesophageal junction (Figs.
1A,
1B,
1C,
1D and
2A,
2B,
2C,
2D). One patient had CT
evidence of a substernal goiter, and six had no evidence of a mediastinal
mass. None of the patients had a CT finding of increased periesophageal
fat.
Correlation of Barium Study and CT Findings
At fluoroscopy, in all seven patients with DES, nonperistaltic contractions
were found only below the level of the carina. This finding corresponded to
the CT finding of significantly greater mean esophageal wall thickness in the
lower thoracic esophagus 5 cm above the gastroesophageal junction (11.9 mm)
than in the upper thoracic esophagus at the level of the aortic arch (5 mm)
and in the midthoracic esophagus at the level of the carina (7 mm) (p
< 0.01). Furthermore, the two patients with marked nonperistaltic
contractions had CT findings of a mean maximal esophageal wall thickness of 14
mm at 5 cm above the gastroesophageal junction (Figs.
1A,
1B,
1C,
1D and
2A,
2B,
2C,
2D), whereas the five patients
with mild or moderate nonperistaltic contractions had a mean maximal
esophageal wall thickness of 11.0 mm at this level (p > 0.05). Our
data suggest that multiple strong nonperistaltic contractions in the lower
thoracic esophagus in patients with DES contribute to the development of
esophageal wall thickening found on CT.
Discussion
DES is an uncommon condition, accounting for only 5–15% of cases of
primary esophageal motility disorders
[1]. DES is characterized
radiographically and manometrically by intermittently weakened or absent
primary esophageal peristalsis interspersed with multiple repetitive
nonperistaltic contractions
[1–3].
Some patients with DES have lumen-obliterating or nearly lumen-obliterating
nonperistaltic contractions, producing a classic corkscrew esophagus on barium
studies [3], but other patients
have nonperistaltic contractions of varying magnitude that are not
lumen-obliterating [7]. It
therefore is important to recognize that nonperistaltic contractions can be of
varying severity in DES and that the absence of a corkscrew esophagus on
barium studies in no way excludes this diagnosis.
Patients with DES tend to be elderly persons presenting with chest pain,
dysphagia, or both [1,
2]. When patients with DES have
chest pain due to high-amplitude nonperistaltic esophageal contractions, drugs
such as calcium channel blockers and long-acting nitrates have been shown to
decrease the amplitude of the contractions, sometimes ameliorating the
symptoms [2]. However,
manometric and radiographic studies of patients with DES have shown that these
patients often have impaired relaxation of the LES
[7,
8] (Figs.
1A,
2A, and
3A). Prabhakar et al.
[7] found that dysphagia was
more common than chest pain in patients with DES, at least partly because of
the high frequency of LES dysfunction in these patients. Such patients may
experience marked relief of dysphagia from endoscopic balloon dilation of the
LES or injection of botulinum toxin at the gastroesophageal junction
[7,
9].
In our study, seven (21%) of 33 patients with evidence of DES on barium
studies had CT evidence of esophageal wall thickening, which was most marked
at the level of the carina and 5 cm above the gastroesophageal junction (Figs.
1A,
1B,
1C,
1D,
2A,
2B,
2C,
2D,
3A,
3B,
3C,
3D). Esophageal wall
thickening on CT is a nonspecific imaging finding resulting from a variety of
causes, including esophagitis and benign and malignant tumors involving the
esophagus. As in our study, however, the pattern of wall thickening can
suggest the correct diagnosis. Six (86%) of our seven patients with DES had
smooth circumferential esophageal wall thickening that extended over a long
segment of the thoracic esophagus from the carina distally toward the
gastroesophageal junction (Figs.
1A,
1B,
1C,
1D and
2A,
2B,
2C,
2D). In a CT study, Nino-Murcia
et al. [4] found smooth
circumferential esophageal wall thickening in three patients with DES. We
therefore believe that DES should be included in the differential diagnosis
when CT shows a relatively long segment of smooth circumferential wall
thickening in the lower half of the thoracic esophagus, particularly in
elderly patients with dysphagia or chest pain. Neoplastic lesions such as
esophageal carcinoma cannot be excluded, however, so a barium study or
endoscopy may be needed for further evaluation.
The cause of the CT finding of marked esophageal wall thickening in
patients with DES is uncertain. The esophageal wall is lined by striated
muscle in the upper third of the esophagus and by smooth muscle in the lower
two thirds. Previous clinical and pathologic studies have shown that because
of hypertrophy of the muscularis propria, esophageal wall thickening occurs in
the lower two thirds of the esophagus in patients with DES and other primary
esophageal motility disorders
[10–13].
In our investigation, CT showed significantly greater esophageal wall
thickening in the lower thoracic esophagus 5 cm above the gastroesophageal
junction than in the upper thoracic esophagus at the level of the aortic arch
or in the midthoracic esophagus at the level of the carina (p <
0.01) in patients with evidence of DES on barium studies. These findings also
corresponded to the presence on barium studies of multiple nonperistaltic
contractions below the level of the carina in all seven patients with DES. We
therefore believe that progressively severe nonperistaltic contractions in the
lower thoracic esophagus in patients with DES cause gradual hypertrophy of the
muscularis propria manifested by esophageal wall thickening on CT scans.
Our investigation had the inherent limitations of a retrospective study,
including selection and interpretation bias. We also had a relatively small
series of patients, because only a minority of those with barium study
findings of DES underwent CT. Patients with more severe symptoms also were
more likely to undergo barium studies, causing additional selection bias.
Because of these biases, our observed frequency of esophageal wall thickening
on CT should not be used as an indication of the prevalence of this CT finding
in patients with DES. Another limitation was the lack of optimal luminal
distention of the esophagus by positive or negative CT contrast agents.
Because underdistention of the lumen can exaggerate apparent esophageal wall
thickening on CT, we might have overestimated the degree of wall thickening in
some patients. Regardless of the degree of luminal distention, however, it is
believed that normal esophageal wall thickness should not exceed 3 mm
[8]. Finally, our study was
limited by the lack of manometry as the reference standard for the diagnosis
of DES. Ott et al. [6],
however, found that fluoroscopic examinations have an accuracy greater than
90% in comparison with manometry for the diagnosis of esophageal motility
disorders. At our hospital, patients are often treated without manometry when
typical findings of DES or other esophageal motility disorders are seen on
barium studies.
In summary, CT revealed marked esophageal wall thickening in seven (21%) of
33 patients who had evidence of DES on barium studies. Furthermore, CT showed
significantly greater esophageal wall thickening in the lower thoracic
esophagus 5 cm above the gastroesophageal junction than in the upper thoracic
esophagus at the level of the aortic arch or in the midthoracic esophagus at
the level of the carina (p < 0.01). This wall thickening
corresponded to the barium study finding of multiple strong nonperistaltic
contractions in the lower thoracic esophagus. Our findings suggest that DES
should be included in the differential diagnosis of the CT finding of smooth
circumferential wall thickening of the lower half of the thoracic esophagus,
particularly in elderly patients with dysphagia or chest pain.
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Abstract
Introduction
