VASCULAR RINGS A CASE - BASED REVIEW Beverley Newman, BSc. MB.Bch. FACR Professor of Radiology Stanford University and Lucile Packard Children s Hospital
Q1,2,3 Frontal chest radiographs on three different individuals. For each case suggest the most likely diagnosis. a. No ring or sling b. Vascular ring very likely c. Vascular ring unlikely d. Pulmonary sling very likely e. Pulmonary sling unlikely
Case 1: 16month girl with respiratory distress
Case 2: 16month girl with respiratory distress
Case 3: 2.5 month girl with respiratory distress
Q4,5,6 Additional lateral chest radiographs on the same three children. For each case suggest the most likely diagnosis. a. No ring or sling b. Vascular ring very likely c. Vascular ring unlikely d. Pulmonary sling very likely e. Pulmonary sling unlikely
Case 1:16month girl with respiratory distress
Case 2: 16month girl with respiratory distress
Case 3: 2.5 month girl with respiratory distress
Q7,8,9 Contrast esophagrams on the same three children. For each case suggest the most likely diagnosis. a. No ring or sling b. Vascular ring very likely c. Vascular ring unlikely d. Pulmonary sling very likely e. Pulmonary sling unlikely
Case1: 16month girl with respiratory distress
Case 2: 16month girl with respiratory distress
Case 3: 2.5 month girl with respiratory distress
Q10,11,12 CT axial images on the 3 cases. For each case suggest the most likely diagnosis. a. No ring or sling b. Vascular ring very likely c. Vascular ring unlikely d. Pulmonary sling very likely e. Pulmonary sling unlikely
Case1: 16month girl with respiratory distress
Case 2: 16month girl with respiratory distress
ase 3: 2.5 month girl with respiratory distress
Chest Radiographic Findings Suggestive of a Vascular Ring Right Aortic arch Descending Aorta on opposite side of arch Anterior bowing of trachea (lateral view)
6 month old with recurrent respiratory infections
Vascular Ring ESOPHAGRAM Not necessary if plain film suggests ring Confirms likely presence of ring May suggest type but not definitive
Imaging Vascular Rings CT Angiography Fast - decreased need for sedation.6mm-1mm axial spiral Timed/triggered dynamic IV contrast (2-3cc/Kg) 2 and 3-D reconstruction Pay attention to parameters and radiation dose Lower kvp (80-100) Automodulation of mas (ref mas 150) Breast shield in girls
Imaging Vascular Rings MR Imaging/Angiography Multiplanar capability/many sequence options. Need specific sequences to optimally evaluate airway Timed/triggered dynamic IV contrast for MRA 2 and 3-D reconstruction of images No ionizing radiation Long study/sedation often required
Vascular Ring combination of vascular/ ligamentous structures encircling the airway COMMON Double Aortic Arch Right arch, aberrant left subclavian artery + ductus UNCOMMON - Left arch, aberrant right subclavian artery + ductus - Right or left circumflex aorta and ductus aberrant subclavian artery - Mirror image right arch + ductus
Imaging Vascular Rings KEY FEATURES Arch location Branching of aorta Compression of airway Diverticulum of Kommerel Descending aorta
DOUBLE AORTIC ARCH DOUBLE AO ARCH WITH ATRETIC LEFT SEGMENT AA ANTERIOR AA C C S DA S DA POSTERIOR
DOUBLE AORTIC ARCH 4 symmetric vessels Bilateral Arches Ipsilateral carotid and subclavian Branches S c C S Compressed trachea
DOUBLE AORTIC ARCH L R R L Compressed airway Descending aorta on left
RIGHT ARCH ABERRANT LEFT SUBCLAVIAN ARTERY AA ANTERIOR DA DK
AAo T E DAo 2.5yo RAA ABERRANT LSCA BRANCH, Mild tracheal Compression, Diverticulum, Lt descending AO
LAA ABERRANT RSCA PLUS DIVERTICULUM
LAA ARSCA BRANCH Mild Tracheal Compression Diverticulum behind trachea ( prior TEF repair) Lt SVC
MIRROR IMAGE RIGHT ARCH RING AA ANTERIOR AA LT INNOM DA DA A
Mirror image right Arch Branching Mild tracheal Compression In Diverticulum Right descending aorta In
Mirror image Rt Arch Branching Mild tracheal Compression Diverticulum Circumflex aorta descending on left
Left Pulmonary Artery Sling Left pulmonary artery arises from RPA Courses posteriorly between the trachea and esophagus
Type I PA Sling Higher level of sling N bronchial branching or tracheal bronchus Associated compression/malacia (trachea/rmsb)
15yo girl with known VSD
15yo girl with known VSD
Type 1 PA sling
LPA Sling Chest Radiographic Findings May be normal Mass posterior to trachea on lateral view Unilateral hyperinflation (Type I) Bilateral hyperinflation or small right lung (Type II). Low T carina
Type II PA Sling ( Ring/Sling complex) Low position of PA sling Horizontal low carina Abnormal airway branching Associated long segment airway stenosis May be right lung hypoplasia/agenesis
5week old male with severe stridor
Newborn male with severe respiratory distress
Newborn male with severe respiratory distress 1 Type IIA LPAS 3 2
49 YO F PREVIOUS TOF REPAIR RIGHT DIAPHRAGMATIC PARALYSIS DECREASED EXERCISE TOLERANCE Previously unrecognized Type IIA PA sling and tracheal stenosis
Tracheal stenosis
LPA Sling Pre &Post
10 day old with tachypnea
10 day old with tachypnea
5 month old male with persistent respiratory symptoms
SUMMARY Vascular rings and slings are often first suspected on the basis of plain chest radiographs There is a wide spectrum of lesions and radiographic appearances Cross-sectional angiography provides the detailed anatomy needed for operative planning of vascular lesions compressing the airway Carefully evaluate and report vascular & airway appearance and relationships Multiple planes, 2D and 3D reconstructions are useful in understanding and communicating the important anatomy
References Vascular Ring/Pulmonary Artery Sling 1. Berdon WE. Rings, slings, and other things: Vascular compression of the infant trachea updated from the mid-century to the millennium the legacy of Robert E. Gross, MD, and Edward B.D. Neuhauser, MD. Radiology 2000; 216:624-632 2. Chan, MS, Chu WC, Cheung KL, Arifi AA, Lam WW. Angiography and dynamic airway evaluation with MDCT in the diagnosis of double aortic arch associated with tracheomalacia. AJR 2005; 185(5): 1248-1251 3. Dodge-Khatami A, Tulevski II, Hitchcock JF, et al. Vascular rings and pulmonary arterial sling: from respiratory collapse to surgical cure, with emphasis on judicious imaging in the hi-tech era. Cardiol Young 2002; 12:96-104. 4. Eichhorn J, Fink C, Delorme S, et al. Rings, slings and other vascular abnormalities. Ultra fast computed tomography and magnetic resonance angiography in pediatric cardiology. Z Kardiol 2004; 93:201-208
References Vascular Rings (cont.) 5. Hernanz-Schulman M. Vascular rings: a practical approach to imaging diagnosis. Pediatric Radiology 2005; 35:961-979 6. Mahboubi S, Meyer JS, Hubbard AM, et al. Magnetic resonance imaging of airway obstruction resulting from vascular anomalies. International J of Pediatric Otorhinolaryngology 1994; 28:111-123. 7. Dillman JR, Attili AK, Agarwal PP, Dorfman AL, Hernandez RJ, Strouse PJ. Common and uncommon vascular rings and slings: a multi-modality review Pediatr Radiol. 2011 Nov;41(11):1440-54 8. Newman B, Cho YA. Left Pulmonary Artery Sling-Anatomy and Imaging. Semin Ultrasound CT MR 2010; 31:158-170.