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2012-07-20-09 Case of the week #333 © Ventriglia www.TheFetus.net


Answer to the case of the week #333


December 6th, 2012 - December 20th, 2012


Flavia Ventriglia*; Vanessa Martucci*; Albana Cerekja**; Angela Caiaro***; Imbornone Orsola***; Lucia Manganaro***.

*   Pediatric Cardiology. Policlinico Umberto I. University “La Sapienza” Rome, Italy;
**  Ultrasound Division, ASL Roma B, Rome, Italy;
*** Radiology Department. Policlinico Umberto I. University “La Sapienza” Rome, Italy.

(Edited by F.G.)

 


Case report

This is the case of a 32-year-old G2P1 with non-contributive familial history. She had been taken Euthyrox treatment due to hypothyroidism and was referred to our cardiology unit for evidence of a chest mass at anomaly scan.

The first examination at our service was performed at 22 weeks. A hyperechoic mass of 22 x 11 mm was evidenced posteriorly to the heart. The mass embraced almost the whole left atrium and part of the left ventricle. Four chamber view and outflow tracts looked normal and there was no obstruction to flow neither in the big arteries nor in the pulmonary veins. The hyperechoic mass had a synchronous motion with the heart. Normal appearance of the heart chambers and outflow tracts and mass pulsation synchronous with the heartbeat suggested an extracardiac intrapericardial mass.

An anechoic area of 10 x 5 mm was evidenced almost centrally in the mass. Color flow didn’t show vascularity at first temptation. Only after decreasing PRF, we could detect some flow with low velocities (30 cm/sec) in the anechoic area. Trying to follow that vascular area, we found that it communicated with the adjacent thoracic aorta by means of a small vascular channel and it bifurcated inside the mass, thus representing an aberrant feeding vessel.

Although findings suggested a lung sequestration, a differential diagnosis with a pericardial teratoma couldn’t be made immediately.

At subsequent examinations performed at 24, 26 and 31 weeks the mass presented an inconsiderable growth (respectively 24, 27 and 29 mm) in agreement with fetal heart growth. At 24 weeks some supraventricular extrasystoles were recorded, some of them blocked, but those disappeared in the following examinations. Furthermore, at 31 weeks only a minimal quantity of pericardial fluid posteriorly to the left ventricle was found and there were no signs of congestive heart failure. All these findings reduced the possibility of an intrapericardial teratoma.

Magnetic resonance imaging was performed at 34 weeks. It demonstrated the extracardiac origin and intrapericardial presence of the mass, which showed an inhomogeneous hyperintensity of signal in T2-weighted images and hypointensity of signal in T1-weighted images.

A planned cesarean section was performed at 38 weeks. A male newborn of 3050 gr of Apgar score of 9/9 at 1/5 min respectively was born.

The mass and its intrapericardial location were confirmed with the echocardiogram soon after the birth. The neonate was asymptomatic until 1 month of age when elective surgery was performed. Median sternotomy, longitudinal pericardiotomy and mass resection were done. At surgery a mass of an ovoid shape was seen, that was adherent to the posterior pericardium in the area corresponding to the dome of the left atrium and in front of the tracheal carina. Furthermore, the mass exteriorized bilaterally embracing posteriorly both pulmonary arteries. It presented an arterial peduncle that originated from the aortic arch.

Histology described the mass as follows:

Macroscopically the mass had a brownish color, spongy consistence and sections presented randomly distributed cystic areas. The external surface of the mass was smooth and covered by pleural tissue. Microscopic examination of the sequestered lung revealed that the mass was formed totally of normal lung tissue with normal bronchi and bronchioles surrounded by incomplete cartilaginous rings. The cystic areas, irregular at times, were lined by ciliated cylindrical epithelium and in the lumen there were frothy mucophagi.

Postoperative recovery was uneventful. Now the little boy is 2 years old, he thrives well and he is symptoms free.

Conclusions

Extralobar pulmonary sequestration should be considered in the presence of a fetal intrapericardial mass.

Images 1, 2: The images show transverse scans of the fetal thorax with a hyperechoic mass of the extralobar intrapericardial lung sequestration located posterior to the heart obtained at 22nd and 24th week of pregnancy.

 

Images 3, 4: 24 weeks of pregnancy; the image 3 shows cystic area within the mass of the intrapericardial extralobar lung sequestration. The image 4 shows Doppler waveform at the level of vascular pedicle feeding the mass of the extralobar intrapericardial lung sequestration.

 

Images 5, 6: The image 5 (26 weeks of pregnancy) shows transverse scan of the fetal thorax with a hyperechoic mass of the extralobar intrapericardial lung sequestration located posterior to the heart. The longest diameter of the lesion was 29 mm.  The image 6 demonstrates small pericardial effusion visible at 31st week of pregnancy.

 

Videos 1, 2, 3, 4, 5, 6, and 7: 22 weeks; the videos 1 and 2 demonstrate normal four chamber view of the heart, while slightly tilted scanning planes depict hyperechoic mass of the intrapericardial lung sequestration (images 3, 4, 5, and 6). The video 7 demonstrates vascularity of the sequestered intrapericardial pulmonary mass.

 

 

 



Definition

Pulmonary sequestration or accessory lung is a congenital anomaly in which a mass of pulmonary parenchyma is separated from the normal lung.

Pulmonary sequestration is classified as extralobar (ELPS) in which a mass of the lung parenchyma possesses a distinct pleural covering separate from the tracheobronchial tree with an arterial blood supply from the systemic vasculature or intralobar (ILS), in which the mass of lung parenchyma is contiguous with the adjacent normal lung. Extralobar pulmonary sequestrations are usually thoracic or abdominal lesions. The accessory lung constituting the sequestration is found lying mostly at the base of the left side of the thorax, but could be found on the right side and in the mediastinum at any level from the neck to below the diaphragm. Intrapericardial lung sequestration is rare with a few cases reported in literature and very few ones diagnosed in utero.

Sonographic diagnosis of intrapericardial lung sequestration

Due to exiguity of cases reported in literature, few is known about ultrasound characteristics of these masses, however they reproduce characteristics of pulmonary sequestrations situated elsewhere. The diagnosis can be achieved as early as the second trimester.

The findings include: a homogeneous echogenic pulsatile mass, well circumscribed, with smooth surface and variable size. Cystic areas or punctuate calcifications may be found within the lesion. Doppler may be helpful to demonstrate the systemic arterial blood supply and define the venous drainage pattern. Multiple supply arteries can be found. Demonstration of a dominant feeding vessel, usually from the aorta or its major vessels, and venous drainage to the pulmonary veins suggests the diagnosis. The mass can displace or compress the heart chambers. Pericardial effusion is not as characteristic as in teratomas. Congestive heart failure or can be demonstrated by pulsed Doppler. Hydrops may occur in case of obstruction to flow.

Differential diagnosis

When a thoracic mass is identified in the fetus, the differential diagnoses of cystic adenomatoid malformations, extralobar pulmonary sequestration, as well as cardiac tumors should be considered.

Associated anomalies

Extralobar sequestration is frequently associated with other congenital extrapulmonary anomalies such as diaphragmatic hernia, pectus excavatum, tracheo­esophageal fistula esophageal duplication, esophageal cyst, bronchogenic cyst, megacolon and congenital heart disease etc.

References

Ahn CM, Kim HJ, Cho HK, et al. A case of intrapericardial extralobar pulmonary sequestration–first case in Korea. Korean J Intern Med 1991;6:85-89.
De Vreede I, Bilardo CM, van Rijn RR, Clur SA, Heij HA. Intrapericardial extralobar pulmonary sequestration presenting as a prenatal intrathoracic mass. Pediatr Cardiol. 2008;29(5):980-2.
Hayashi AH, McLean DR, Peliowski A, Tierney AJ, Finer NN. A rare case of intrapericardial mass in a neonate J Pediatr Surg 1992;27:1361-3.
Heithoff KB, Sane SM, Williams HJ, Jarvis CJ, Carter J, Kane P. et al. Bronchopulmonary forgut malformations: a unifying ethiological concept. AJR 1976; 126:46-55.
Levi A, Findler M, Dolfin T, Di Segni E, Vidne BA. Intrapericardial extralobar pulmonary sequestration in a neonate. Chest 1990;98(4):1014-5.
Romero-Pilu-Jeanty-Ghidini-Hobbins. The lungs. www.sonoworld.com/Client/Fetus/Files/pcda/PDCA_lungs.pdf ©1987-2002
Sade RM, Clouse M, Ellis FH Jr: The spectrum of pulmonary sequestration. Ann Thorac Surg 1974;18:644.
Spencer H. Pathology of the lung, 2nd ed. London: Pergamon Press, 1968;79.
Wax JR, Pinette MG, Landes A, Blackstone J, Cartin A. Intrapericardial extralobar pulmonary sequestration-ultrasound and magnetic resonance prenatal diagnosis. Am J Obstet Gynecol. 2002;187(6):1713-4.
Witlox RS, Lopriore E, Oepkes D. Prenatal interventions for fetal lung lesions. Prenat Diagn 2011; 31:628–636.
Yildiz K, Özcan N, Çebi M, Köse N, Karakaya F. Intrapericardial Extralobar Pulmonary Sequestration: Unusual Cause of Hydrops Fetalis. JUM 2005;24:391-393.

 

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