AJR 2002; 178:1275-1279
© American Roentgen Ray Society
Imaging Findings in Pediatric Patients with Persistent Airway Symptoms After Surgery for Double Aortic Arch
Robert J. Fleck1,2,
Preeyacha Pacharn1,3,
Bradley L. Fricke1,
Matthew A. Ziegler1,
Robin T. Cotton4 and
Lane F. Donnelly1
1 Department of Radiology, Children's Hospital Medical Center, 3333 Burnet Ave.,
Cincinnati, OH 45229-3039.
2 Present address: Department of Radiology, Naval Medical Center, San Diego, CA
92134-1204.
3 Present address: Department of Radiology, Mahidol University, Bangkok,
Thailand 10700.
4 Division of Otolaryngology, Children's Hospital Medical Center, Cincinnati, OH
45229.
Received August 30, 2001;
accepted after revision October 22, 2001.
Address correspondence to L. F. Donnelly.
Abstract
OBJECTIVE. The purpose of this study was to review the imaging
findings of children referred for cross-sectional imaging to evaluate
persistent airway symptoms after surgical therapy for double aortic arch.
CONCLUSION. Airway narrowing is clearly shown on cross-sectional
imaging in patients with persistent airway symptoms after surgical therapy for
double aortic arch. Two patterns of airway compression are typically seen:
narrowing of the trachea at the level of the postsurgical arch and narrowing
of the left main bronchus as a result of compression from a midline descending
aorta. Both patterns may be seen in patients regardless of whether the left or
the right arch has been ligated.
Introduction
Extrinsic tracheal compression caused by vascular rings, such as double
aortic arch, can present with life-threatening episodes of stridor, cyanosis,
or apnea. Surgical correction of the underlying vascular ring has been shown
to be an effective treatment for such patients, with 70-86% of patients having
complete resolution of symptoms after the surgery
[1,2,3,4,5].
However, as many as 30% of pediatric patients may have persistent airway
symptoms after initial surgical relief of the vascular ring
[1,2,3,4,5].
These symptoms may be related to tracheomalacia, persistent extrinsic airway
compression, or a combination of the two. Some of these patients who have
persistent symptoms may benefit from a second operation, such as aortopexy,
other vascular suspension procedures, or airway resection or reconstruction
[1,
2,
4]. In one series, 11% of
patients required a second operation to relieve airway symptoms
[1]. It has been suggested that
the patient with persistent airway symptoms after surgical therapy of a
vascular ring be evaluated with both bronchoscopy and cross-sectional imaging,
such as MR imaging or helical CT
[1,
2]. The purpose of our study
was to review the imaging findings of children referred for cross-sectional
imaging who had persistent airway symptoms after surgical therapy for double
aortic arch.
Materials and Methods
We reviewed the records of CT and MR imaging examinations in pediatric
patients referred to our institution to evaluate for extrinsic airway
compression for persistent airway symptoms after surgery for double aortic
arch. MR imaging studies from a 5-year period (1996-2000) were reviewed. All
MR imaging studies were performed on a 1.5-T scanner (General Electric Medical
Systems, Milwaukee, WI) with sequences including, at minimum, T1-weighted
images in the axial, sagittal, and coronal planes. CT examinations were
reviewed from a 1-year period (1999-2000) after the installation of a
multidetector CT scanner (Light-Speed; General Electric Medical Systems). CT
studies were performed after the administration of IV contrast material. CT
parameters included 2.5-mm slice thickness; 120 kV; and weight-based, low-dose
tube current [6].
Patient charts and imaging studies were reviewed in identified cases.
Parameters recorded included the age of the patient at the time of diagnosis
of double aortic arch by imaging, the type of imaging performed (CT or MR
imaging), the aortic arch ligated at surgery (left vs right), the duration of
time between surgical repair of the double aortic arch and the time of
reimaging, symptoms leading to reimaging, and treatment after imaging was
performed. The imaging studies were reviewed for abnormal caliber of the
airway and extrinsic structures causing compression at the level of airway
narrowing. Patterns of extrinsic compression were reviewed between patients.
Imaging findings were compared with findings seen at bronchoscopy. The
retrospective review of this material was approved by our institutional review
board.
Results
Our review of these studies yielded four patients (three males and one
female, whose ages at diagnosis ranged from 2 days to 1 year) who had been
referred for imaging because of persistent airway symptoms after surgical
treatment for double aortic arch (Table
1). All patients had stridor or other noisy breathing. Two also
experienced symptoms of obstructive sleep apnea. Two of the patients had poor
growth and failure to thrive.
View this table:
[in this window]
[in a new window]
|
TABLE 1 Summary of Findings in Four Patients with Persistent Airway Symptoms
After Surgery for Double Aortic Arch
|
|
Concerning the initial surgery, two of the patients had ligation of the
left and two had ligation of the right aortic arch. The interval from the
initial diagnosis and treatment of the double aortic arch and the request for
reimaging ranged from 1 month to 13 years. All patients referred for imaging
were evaluated with bronchoscopy during the same time period.
MR imaging was used to evaluate the persistent symptoms in three patients
and CT was used in one patient. All patients showed at least one area of
abnormal airway caliber, and two patients had two discrete areas of
abnormality. We found two discrete patterns of airway narrowing and extrinsic
compression. Three patients had narrowing of the airway at the level of the
remaining aortic arch. The airway narrowing was immediately abutting the
intact aortic arch and the remaining anterior portion of the ligated arch that
was retained to connect to the ipsilateral subclavian and common carotid
arteries (Fig.
1A,1B,1C,1D).
In two patients, the left arch was present, and in two patients the right arch
was present.
View larger version (94K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1A. —Airway compression at level of trachea in 1-year-old girl
after repair of double aortic arch. Contrast-enhanced CT image obtained at
time of initial diagnosis shows double aortic arch (arrowheads) with
marked airway compression (arrow).
|
|
View larger version (78K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1B. —Airway compression at level of trachea in 1-year-old girl
after repair of double aortic arch. Contrast-enhanced CT image obtained at
time of reimaging 1 month after surgery shows trachea (large arrow)
to be narrowed between left arch (small arrows) and persistent
portion of right arch (arrowhead), which was retained to connect to
right subclavian and common carotid arteries.
|
|
View larger version (109K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1C. —Airway compression at level of trachea in 1-year-old girl
after repair of double aortic arch. Surface-rendered three-dimensional CT
image shows narrowing (arrows) of caliber of trachea (T) at level of
arch. Esophagus (E) is also dilated and air-filled above this level. Some
aerated lung is also present.
|
|
Three patients had narrowing of the left main bronchus. In all three
patients, the descending aorta was in an abnormal midline position,
immediately anterior to the spine, instead of in the typical paraspinal
location. In such patients, the abnormal position of the descending aorta
caused abnormal stacking of structures in the confined space between the spine
and the manubrium, which led to compression of the left main bronchus between
the abnormally positioned descending aorta posteriorly and the pulmonary
arteries anteriorly (Fig.
2A,2B,2C,2D,2E).
View larger version (97K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2A. —Airway compression at level of trachea and left main bronchus
in 17-month-old boy after repair of double aortic arch. CT image from time of
initial diagnosis at 1 week of life shows double aortic arch compressing
trachea. Left arch (arrows) is larger than right arch
(arrowheads). Endotracheal tube is in trachea. Patient underwent
surgical ligation of smaller, right arch.
|
|
View larger version (127K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2B. —Airway compression at level of trachea and left main bronchus
in 17-month-old boy after repair of double aortic arch. Axial T1-weighted MR
image obtained after surgery at level of persistent left arch (A) and anterior
segment of right arch (arrowhead) shows trachea (arrow) to
be oblong and slightly narrowed.
|
|
View larger version (133K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2D. —Airway compression at level of trachea and left main bronchus
in 17-month-old boy after repair of double aortic arch. Axial T1-weighted MR
image obtained at lower level shows descending aorta (D) to be in midline
position, immediately anterior to spine. Left main bronchus (arrow)
is compressed between abnormally positioned descending aorta and right
pulmonary artery (P) and is much narrower in diameter than right main bronchus
(arrowhead).
|
|
View larger version (105K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2E. —Airway compression at level of trachea and left main bronchus
in 17-month-old boy after repair of double aortic arch. Endoscopic image,
oriented as MR images in B and D, shows compression of left main
bronchus (arrows), which is much smaller in diameter than right main
bronchus (arrowheads). Narrowing was fixed and pulsatile.
|
|
Two of the patients required tracheotomy to treat their airway symptoms.
Two patients were treated without surgery, but they did require continuous
positive-pressure ventilation during sleep for treatment of their obstructive
sleep apnea.
Discussion
Cross-sectional imaging has an important role in the evaluation of children
with potential extrinsic airway compression, and MR imaging has traditionally
been the imaging modality of choice in evaluating these patients
[7,
8]. However, with the recent
increases in speed of acquisition and multiplanar reformat capability, helical
CT has begun to play an increasingly larger role in the evaluation of these
patients [7]. CT now can
usually provide all of the needed anatomic information on the potential of
extrinsic airway compression that is provided by MR imaging but with a lower
incidence of examinations in which sedation is required
[9]. The choice of which
modality is used—CT or MR imaging—is often made on an
institutional basis. Cross-sectional imaging has also been shown to be helpful
in the evaluation of potential extrinsic airway compression after surgical
procedures [10].
As many as 30% of pediatric patients who undergo surgical therapy for
vascular rings may have persistent airway symptoms
[2]. In one review specifically
of patients with double aortic arch, 24% had persistent airway symptoms after
surgery. Cross-sectional imaging plays an important role in the evaluation of
such patients [1,
2]. We have described the
cross-sectional imaging findings in four patients who had persistent airway
symptoms and were referred for cross-sectional imaging. All four of these
patients had at least one area of airway narrowing seen on imaging and two of
the patients had two discrete areas of narrowing shown.
Two patterns of airway compression were identified, and these were not
mutually exclusive. One pattern was extrinsic compression of the trachea at
the level of the aortic arch. The intact arch and remaining anterior portion
of the ligated arch were immediately abutting the airway at the level of
narrowing consistent with extrinsic airway compression. The endoscopic
evaluation also revealed fixed, pulsatile compression of the airway consistent
with extrinsic compression, rather than tracheomalacia. We define
tracheomalacia as an underlying weakness of the trachea, in the absence of
extrinsic compression, that results in dynamic decrease in the airway caliber.
A component of malacia, or airway wall weakening, is often associated with
long-standing extrinsic airway compression. We are not able to exclude the
presence of a concurrent component of airway wall weakening in addition to the
extrinsic compression. It has been reported that patients with extrinsic
airway compression after initial repair for double aortic arch do benefit from
aortopexy, also suggesting that persistent extrinsic compression does play
some role [1,
2,
4]. This pattern was seen both
in patients who had the right arch ligated surgically and in those who had the
left arch ligated, suggesting that the arch ligated is not a predisposing
factor to developing this type of airway narrowing.
The other pattern of airway narrowing identified was that of left main
bronchus narrowing associated with a midline positioned descending aorta.
Midline descending aorta was first described as a cause of airway compression
in 1995 [11]. Other
investigators then showed that a midline position of the descending aorta was
more often present in children with left main bronchus compression than in
nonsymptomatic patients [12].
Normally, the descending aorta sits in a paraspinal location. When the
descending aorta lies immediately anterior to the spine, there is abnormal
stacking of structures in the confined space between the spine and the
anterior chest wall. In such patients, the airway—most typically the
left main bronchus—is extrinsically compressed between the abnormally
positioned descending aorta posteriorly and the pulmonary arteries anteriorly
[11]. Midline descending
aorta—airway compression syndrome has been described as an isolated
lesion [11], but it has also
been reported to occur as a phenomenon associated with hypoplastic right lung
and resultant mediastinal shift or with a right arch and left-sided descending
aorta [8]. Anatomically,
patients with double aortic arch are probably prone to have a midline position
of the descending aorta related to dual-sidedness of their bilateral arches.
This pattern of airway compression was seen in patients with the left aortic
arch ligated and in those with the right aortic arch ligated, suggesting that
the pattern is independent of the dominant arch.
In conclusion, we found that airway narrowing is clearly shown on
cross-sectional imaging in patients with persistent airway symptoms after
surgical therapy for double aortic arch. Such patients typically show two
patterns of airway compression: narrowing of the trachea at the level of the
postoperative arch and narrowing of the left main bronchus caused by
compression from a midline descending aorta. These patterns may be seen in
patients regardless of whether the left or right arch was ligated.
References
-
Erwin EA, Gerber ME, Cotton RT. Vascular compression of the airway:
indications for and results of surgical management. Int J Pediatr
Otorhinolaryngol
1997;40:155
-162[Medline]
-
Anand R, Dooley KJ, Williams WH. Vincent RN. Follow-up of surgical
correction of vascular anomalies causing tracheobronchial compression.
Pediatr Cardiol
1994;15:58
-61[Medline]
-
Horvath P, Hucin B, Hruda J, et al. Intermediate to late results of
surgical relief of vascular tracheobronchial compression. Eur J
Cardiothorac Surg
1992;6:366
-371[Abstract]
-
Han MT, Hall DG, Manche A, Rittenhouse EA. Double aortic arch
causing tracheoesophageal compression. Am J Surg
1993;165:628
-631[Medline]
-
Sebening C, Jakob H, Tochtermann U, et al. Vascular
tracheobronchial compression syndromes: experience in surgical treatment and
literature review. Thorac Cardiovasc Surg
2000;48:164
-174[Medline]
-
Donnelly LF, Emery KH, Brody AS, et al. Minimizing radiation dose
for pediatric body applications of single-detector helical CT: strategies at a
large children's hospital. AJR
2001;176:303
-306[Free Full Text]
-
Katz M, Konen E, Rozenman J, Szeinberg A, Itzchak Y. Spiral CT and
3D image reconstruction of vascular rings and associated tracheobronchial
anomalies. J Comput Assist Tomogr
1995;19:564
-568[Medline]
-
Donnelly LF, Strife JL, Bisset GS III. The spectrum of extrinsic
lower airway compression in children: MR imaging. AJR
1997;168:59
-62[Free Full Text]
-
Pappas JN, Donnelly LF, Frush DP. Reduced frequency of sedation of
young children with multisection helical CT. Radiology
2000;215:897
-899[Abstract/Free Full Text]
-
Donnelly LF, Strife JL, Bailey WW. Extrinsic airway compression
secondary to pulmonary arterial conduits: MR findings. Pediatr
Radiol 1997;27:268
-270[Medline]
-
Donnelly LF, Bisset GS III, McDermott B. Anomalous midline location
of the descending aorta: a cause of compression of the carina and left
mainstem bronchus in infants. AJR
1995;164:705
-707[Free Full Text]
-
Hungate RG, Newman B, Meza MP. Left mainstem bronchial narrowing: a
vascular compression syndrome? Evaluation by magnetic resonance imaging.
Pediatr Radiol
1998;28:527
-532[Medline]
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
|
|
 
K. Alsenaidi, R. Gurofsky, T. Karamlou, W. G. Williams, and B. W. McCrindle
Management and Outcomes of Double Aortic Arch in 81 Patients
Pediatrics,
November 1, 2006;
118(5):
e1336 - e1341.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. S. M. Chan, W. C. W. Chu, K. L. Cheung, A. A. Arifi, and W. W. M. Lam
Angiography and Dynamic Airway Evaluation with MDCT in the Diagnosis of Double Aortic Arch Associated with Tracheomalacia
Am. J. Roentgenol.,
November 1, 2005;
185(5):
1248 - 1251.
[Full Text]
[PDF]
|
|
|
|
|
|
|
G. Shanmugam, K. Macarthur, and J. Pollock
Surgical Repair of Double Aortic Arch: 16-year Experience
Asian Cardiovasc Thorac Ann,
March 1, 2005;
13(1):
4 - 10.
[Abstract]
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
