European Journal of Radiology, 13 (1991) 138-142
138
EURRAD
0 1991 Elsevier Science Publishers
B.V. All rights reserved.
0720-048X/91/$03.50
00181
CT diagnosis of isolated systemic supply to the lung: a congenital broncho-pulmonary vascular malformation Josep M. Mata ‘, Jo& Cheres ‘Servicio de Radiodiagnhtico
’
and Xavier Lucaya2
de1 Hospital de la Santa Creu i Sam Pau J. and 2Servicio de Radiodiagnhtico Vail d’tlebrh,
(Received
Give&tat
16 October
Authoma
1990; accepted
Key words: Thorax, CT; Thorax, anomalies;
de Barcelona,
Barcelona,
after revision
19 February
Thorax, vascular malformation;
Introduction Isolated systemic supply to the normal lung (ISSNL) is a rare congenital anomaly, first described by Hurber in 1777 [ 11. Many cases have since been published, diagnoses being made by necropsy, surgery or more recently by angiography [l-15]. However, only one case in the literature has been studied by CT and the description of the findings were schematic [ 151. We present the CT findings in two patients with this rare malformation. In both cases CT provided sufficient data for the diagnosis. Case 1 A 5-year-old boy presented with a 2-year history of continuous murmur in the lower right hemithorax. A chest radiography (Fig. la) showed several tubular shadows in the right lower lobe, partially hidden by the diaphragm. Contrast-enhanced CT (Fig. lb and c) showed vascular structures arising from the aorta, perfusing the posterior segments of the right lower lung which were aerated and without any signs of disease. Aortography (Fig. Id) confirmed the existence of an anomalous artery originating in the abdominal aorta
Address for reprints: J.M. Mata, M.D., Servicio de Radiodiagnostico, Hospital de la Santa Creu i Sant Pau, Avda. S. Antoni M. Claret, 167, 08025 - Barcelona, Spain.
de la Clinica Infant2 de la C.S.
Spain
1991)
Computed
tomography,
lung
and perfusing the right basal segments. Venous return was by the right lower pulmonary vein. Pulmonary arteriography demonstrated a lack of perfusion of the segments supplied by the systemic artery. With the diagnosis of IS SNL a right thoracotomy was performed and the anomalous vessel was ligated. Ischemia during surgery motivated partial resection of the right lower lobe. The removed pulmonary parenchyma was normal. Case 2 A 28-year-old woman presented with a murmur in the left hemithorax first detected at 15 years of age. History disclosed hemoptysis at 7 years of age. Hemoptysis appeared again 5 months before the first visit to our centre. Alveolar condensation was detected in the left lower lobe at that time. Two months later she had a third episode of hemoptysis. On admission, the chest radiograph showed a nodular shadow in the left lower lobe. Bronchoscopy was normal. Contrastenhanced CT (Fig. 2a and b) revealed an anomalous artery arising from the aorta coursing into the pulmonary ligament and perfusing the basal segments of the left lower lobe. The pulmonary parenchyma appeared totally aerated and free of disease. Aortography (Fig. 2c) confirmed these findings. Venous return was via the left inferior pulmonary vein. Pulmonary arteriography (Fig. 2d) demonstrated lack of perfusion of the area supplied by the systemic artery. The patient refused surgery.
a
b
Fig. 1. (a) Multiple tubular images (arrows) in the right lower lobe converging towards the lowest portion of the cardiophrenic angle. (b) The anomalous vessel (arrow) is visible in CT crossing the mediastinum and entering the right lower lobe. (c) Lung window shows no signs of disease in the pulmonary parenchyma. The branches of the anomalous artery (arrow) are visible. (d) Aortography confirms the presence of an anomalous artery (arrows) arising from the abdominal aorta.
Fig. 2. (a) CT at the level of the pulmonary ligament shows a thick artery (arrows) arising from the descending aorta and penetrating into the pulmonary ligament. (b) Lung window shows the branches of the systemic vessels. There are no signs of pulmonary disease. The frontier between the segment irrigated by the systemic artery and by the pulmonary artery (arrows) is clearly visible. (c) Aortography confirms the presence of a large systemic artery (arrows) irrigating part of the left lower lobe. (d) The pulmonary arteriogram demonstrates lack of vascularization of the segments irrigated by the systemic artery and a decrease in the calibre of the left lower lobar artery.
141
Discussion Aberrant systemic arterial supply to a lobe of the lung can occur as an isolated finding or be associated with anomalous pulmonary tissue [ 91. Pryce [ 1,161 was the first to classify pulmonary malformations with systemic perfusion and to employ the term “sequestration”. He classified systemic vascularization of the lung into three types according to whether it perfused normal lung, abnormal lung with no connection to the bronchial tree, or both. In the seventies, the term ‘sequestration spectrum’ [ 17-191 was used to encompass all pulmonary malformations either isolated or combining cystic pulmonary disease and anomalies of arterial or venous vascularization. In 1987 Clements and Warner proposed a new approach to pulmonary congenital malformations [ 201. They introduced the term ‘pulmonary malinosculation’ to describe a congenital abnormal connection or opening of one or more components of the bronchopulmonary-vascular complex. The various combinations of these components give rise to a wide spectrum of abnormalities. The lesions thus formed can then be classified simply according to their abnormal anatomical components. The classification is constructed in three steps. The first step describes the abnormality of the bronchopulmonary airway or arterial blood supply, or both. The possible combinations of these two components form a spectrum of lesions. At one end of the spectrum is absence or abnormality of bronchopulmonary airway with normal blood supply (bronchial pulmonary malinosculation). At the other end of the spectrum is an anomalous arterial supply to an area of normal lung (arterial pulmonary malinosculation). In between are all the combinations of abnormal bronchial and arterial connections (bronchoarterial pulmonary malinosculation). Heitzman [21] proposes a similar classification, with a normal lung perfused by systemic arteries at one end of the sequestration spectrum. At the opposite end there is anomalous pulmonary tissue similar to that found in sequestration, but without systemic perfusion. Between the two there are six pathological processes (congenital lobar emphysema, bronchogenic cyst, congenital cystic adenomatoid malformation, hypogenetic lung syndrome, bronchopulmonary sequestration and pulmonary arteriovenous malformation) with a high degree of overlapping between them, rendering classification difficult and in some cases making it impossible to group the pathologic findings into a definite entity. The prototype of these anomalies is pulmonary sequestration, defined as a congenital pulmonary malformation in which there is a mass of nonfunctioning pulmonary tissue, unattached to the bronchial tree, per-
fused by systemic arteries. If the anomalous arteries perfuse normal pulmonary tissue, it is considered a different malformation, called isolated systemic supply to normal lung (ISSNL) [ 121. In ISSNL, patients are usually asymptomatic, although there may exist a continuous murmur on the thoracic wall or left ventricular growth and heart failure secondary to left-to-left shunt [ 111. Hemoptysis has occasionally been described, as in our second case [ 1.51. Associated diaphragmatic defects may occasionally be seen [2,9]. Chest radiography shows increased density in the affected lung. It is sometimes possible to recognize well-defined tubular or rounded images produced by the anomalous vessels. The pulmonary parenchyma does not present any other changes, apart from the exceptional cases of bleeding. Bronchoscopy and bronchography are normal. Aortography shows the systemic vessel arising from the aorta and perfusing the affected lung without direct communication between the systemic artery and the pulmonary vein. Pulmonary angiography shows a decrease in the calibre or absence of the pulmonary branches perfusing the anomalous zone. CT has been used successfully in the study of congenital pulmonary malformations [ 221. The only case of ISSNL studied by CT in the literature [ 151 did not include a detailed description of the findings. In our two cases, CT enabled a definitive diagnosis revealing the characteristic signs of ISSNL, a systemic artery and absence of pathology of the underlying lung. In other entities with systemic vascularization, namely pulmonary sequestration, the anomalous artery is identified by CT in only 40% of cases [22], perhaps due to the fact that pulmonary disease hampers visualization of the artery. Visualization of the anomalous vessel and its intrapulmonary pathway in ISSNL is probably facilitated by the absence of pulmonary involvement. The majority of cases of IS SNL appear to have a single artery with a thick calibre, probably yet another factor enabling easy identification by CT. Differential diagnosis with sequestration is possible as pulmonary involvement is always seen by CT in true sequestration [ 22-261. Differential diagnosis with other vascular malformations without parenchymatous involvement is not required as the AV malformation comes from the pulmonary artery, has an anomalous venous return and does not perfuse the pulmonary parenchyma. Although our findings need confirmation in further studies, we believe CT should be the initial method of study when ISSNL is suspected as it provides rapid, non-invasive identification of the systemic vascularization and demonstrates the absence of pulmonary involvement, both characteristic signs of this entity.
142
References 1 Pryce DM, Holmes Sellers T, Blair LG. Intralobar sequestration of lung associated with an abnormal pulmonary artery. Br J Surg 1947; 35: 18-29. 2 Cole FH, Alley FH, Jones. Aberrant systemic arteries to the lower lung. Surg Gynecol Obstet 1951: 93: 589-596. 3 Campbell DC, Murney JA, Dominy DE. Systemic arterial blood supply to a normal lung. JAMA 1962; 182: 497-499. 4 Painter RL, Billig DM, Epstein I. Anomalous systemic arterialization of the lung without sequestration. N Engl J Med 1968; 279: 866-867. 5 Scott LP, Perry LW. Systemic artery-pulmonary vein listulas. Am J Cardiol 1969; 23: 872-876. 6 Litwin SB, Plauth WH, Nadas AS. Anomalous systemic arterial supply to the lung causing pulmonary-artery hypertension. N Engl J Med 1970; 283: 1098-1099. 7 Hessel EA, Boyden EA, Stamm SJ, Sauvage LR. High systemic origin of the sole artery to the basal segments of the left lung: findings, surgical treatment, and embryologic interpretation. Surgery 1970; 67: 624-632. 8 Ennis JT, Moule NJ, Woo-Ming M. Intralobar pulmonary sequestration in association with bilateral systemic arterialization of the lungs. Br J Radio1 1972; 45: 945-948. 9 MacPherson RI, Whytehead L. Pseudosequestration. J Can Assoc Radio1 1977: 28: 17-25. 10 Currarino G, Willis K, Miller W. Congenital fistula between an aberrant systemic artery and a pulmonary vein without sequestration. J Pediatr 1975; 87: 554-557. 11 Levine MM, Nude1 DB, Gootman N, Wolpowitz A, Wisoff BG. Pulmonary sequestration causing congestive heart failure in infancy. Ann Thorac Surg 1982: 34: 581-585. 12 Kirks DR, Kane PE, Free EA, Taybi H. Systemic arterial supply to normal basilar segments ofthe left lower lobe. AJR 1976; 126: 817-821. 13 Ishihara Y, Fukuda R, Awaya Y et al. Anomalous systemic arterial supply to the basal segments of the lung presenting with a murmur. Eur J Pediatr 1979; 131: 125-131. 14 Makinen ED, Merikanto J, Rikalainen J, Satokari K. Intralobar
15
16
17 18
19 20
21
22
23
24
25 26
pulmonary sequestration without alteration of pulmonary parenchyma. Pediatr Radio1 1981; 10: 237-240. Flisak ME, Chorasekar AJ, Marsan RE, Mumtaz ALI M. Systemic arterialization of lung without sequestration. AJR 1982; 138: 751-753. Pryce DM. Lower accessory pulmonary artery with intralobar sequestration of lung: report of seven cases. J Path01 Bacterial 1946; 58: 457-461. Sade RM, Clouse M. Ellis FH. The spectrum of pulmonary sequestration. Ann Thorac Surg 1974; 18: 644-658. Zumbro GL, Treasure RL, Seitter G, Strevey TE, Brott W, Green DC. Pulmonary sequestration: a broad spectrum of bronchopuhnonary foregut abnormalities. AnnThorac Surg 1975; 20: 161-169. Flye MW, Conley M, Silver D. Spectrum of pulmonary sequestration. Ann Thorac Surg 1976; 22: 478-482. Clements BS, Warner JO. Pulmonary sequestration and related congenital bronchopulmonary-vascular malformations: nomenclature and classification based on anatomical and embryological considerations. Thorax 1987; 42: 401-408. Heitzman ER. Anomalies of pulmonary parenchymal and peripheral vascular development: the sequestration spectrum. In: Heitzman ER, ed. The lung. Radiologic-pathoIogic correlations, 2nd edn. St. Louis: Mosby Company, 1984; 17-19. Mata JM, Caceres J, Lucaya J, Garcia-Conesa JA. CT in congenital malformations of the lung. RadioGraphics 1990; 10: 65 l-674. Hochhauser L, Gray RR, St. Louis EL et al. Computed tomographic diagnosis of pulmonary sequestration. Comput Radio1 1983; 7: 295-299. Pedersen ML, Lequire MH, Spies JB, Lado WA. Computed tomography of intralobar bronchopulmonary sequestration supplied from the renal artery. J Comput Assist Tomogr 1988; 12: 874-875. Paul DJ, Mueller CF. Pulmonary sequestration. J Comput Assist Tomogr 1982; 6: 163-165. Miller PA, Williamson BRJ, Minor GR, Buschi AJ. Pulmonary sequestration: visualization of the feeding artery by CT. J Comput Assist Tomogr 1982; 6: 828-830.
138
EURRAD
0 1991 Elsevier Science Publishers
B.V. All rights reserved.
0720-048X/91/$03.50
00181
CT diagnosis of isolated systemic supply to the lung: a congenital broncho-pulmonary vascular malformation Josep M. Mata ‘, Jo& Cheres ‘Servicio de Radiodiagnhtico
’
and Xavier Lucaya2
de1 Hospital de la Santa Creu i Sam Pau J. and 2Servicio de Radiodiagnhtico Vail d’tlebrh,
(Received
Give&tat
16 October
Authoma
1990; accepted
Key words: Thorax, CT; Thorax, anomalies;
de Barcelona,
Barcelona,
after revision
19 February
Thorax, vascular malformation;
Introduction Isolated systemic supply to the normal lung (ISSNL) is a rare congenital anomaly, first described by Hurber in 1777 [ 11. Many cases have since been published, diagnoses being made by necropsy, surgery or more recently by angiography [l-15]. However, only one case in the literature has been studied by CT and the description of the findings were schematic [ 151. We present the CT findings in two patients with this rare malformation. In both cases CT provided sufficient data for the diagnosis. Case 1 A 5-year-old boy presented with a 2-year history of continuous murmur in the lower right hemithorax. A chest radiography (Fig. la) showed several tubular shadows in the right lower lobe, partially hidden by the diaphragm. Contrast-enhanced CT (Fig. lb and c) showed vascular structures arising from the aorta, perfusing the posterior segments of the right lower lung which were aerated and without any signs of disease. Aortography (Fig. Id) confirmed the existence of an anomalous artery originating in the abdominal aorta
Address for reprints: J.M. Mata, M.D., Servicio de Radiodiagnostico, Hospital de la Santa Creu i Sant Pau, Avda. S. Antoni M. Claret, 167, 08025 - Barcelona, Spain.
de la Clinica Infant2 de la C.S.
Spain
1991)
Computed
tomography,
lung
and perfusing the right basal segments. Venous return was by the right lower pulmonary vein. Pulmonary arteriography demonstrated a lack of perfusion of the segments supplied by the systemic artery. With the diagnosis of IS SNL a right thoracotomy was performed and the anomalous vessel was ligated. Ischemia during surgery motivated partial resection of the right lower lobe. The removed pulmonary parenchyma was normal. Case 2 A 28-year-old woman presented with a murmur in the left hemithorax first detected at 15 years of age. History disclosed hemoptysis at 7 years of age. Hemoptysis appeared again 5 months before the first visit to our centre. Alveolar condensation was detected in the left lower lobe at that time. Two months later she had a third episode of hemoptysis. On admission, the chest radiograph showed a nodular shadow in the left lower lobe. Bronchoscopy was normal. Contrastenhanced CT (Fig. 2a and b) revealed an anomalous artery arising from the aorta coursing into the pulmonary ligament and perfusing the basal segments of the left lower lobe. The pulmonary parenchyma appeared totally aerated and free of disease. Aortography (Fig. 2c) confirmed these findings. Venous return was via the left inferior pulmonary vein. Pulmonary arteriography (Fig. 2d) demonstrated lack of perfusion of the area supplied by the systemic artery. The patient refused surgery.
a
b
Fig. 1. (a) Multiple tubular images (arrows) in the right lower lobe converging towards the lowest portion of the cardiophrenic angle. (b) The anomalous vessel (arrow) is visible in CT crossing the mediastinum and entering the right lower lobe. (c) Lung window shows no signs of disease in the pulmonary parenchyma. The branches of the anomalous artery (arrow) are visible. (d) Aortography confirms the presence of an anomalous artery (arrows) arising from the abdominal aorta.
Fig. 2. (a) CT at the level of the pulmonary ligament shows a thick artery (arrows) arising from the descending aorta and penetrating into the pulmonary ligament. (b) Lung window shows the branches of the systemic vessels. There are no signs of pulmonary disease. The frontier between the segment irrigated by the systemic artery and by the pulmonary artery (arrows) is clearly visible. (c) Aortography confirms the presence of a large systemic artery (arrows) irrigating part of the left lower lobe. (d) The pulmonary arteriogram demonstrates lack of vascularization of the segments irrigated by the systemic artery and a decrease in the calibre of the left lower lobar artery.
141
Discussion Aberrant systemic arterial supply to a lobe of the lung can occur as an isolated finding or be associated with anomalous pulmonary tissue [ 91. Pryce [ 1,161 was the first to classify pulmonary malformations with systemic perfusion and to employ the term “sequestration”. He classified systemic vascularization of the lung into three types according to whether it perfused normal lung, abnormal lung with no connection to the bronchial tree, or both. In the seventies, the term ‘sequestration spectrum’ [ 17-191 was used to encompass all pulmonary malformations either isolated or combining cystic pulmonary disease and anomalies of arterial or venous vascularization. In 1987 Clements and Warner proposed a new approach to pulmonary congenital malformations [ 201. They introduced the term ‘pulmonary malinosculation’ to describe a congenital abnormal connection or opening of one or more components of the bronchopulmonary-vascular complex. The various combinations of these components give rise to a wide spectrum of abnormalities. The lesions thus formed can then be classified simply according to their abnormal anatomical components. The classification is constructed in three steps. The first step describes the abnormality of the bronchopulmonary airway or arterial blood supply, or both. The possible combinations of these two components form a spectrum of lesions. At one end of the spectrum is absence or abnormality of bronchopulmonary airway with normal blood supply (bronchial pulmonary malinosculation). At the other end of the spectrum is an anomalous arterial supply to an area of normal lung (arterial pulmonary malinosculation). In between are all the combinations of abnormal bronchial and arterial connections (bronchoarterial pulmonary malinosculation). Heitzman [21] proposes a similar classification, with a normal lung perfused by systemic arteries at one end of the sequestration spectrum. At the opposite end there is anomalous pulmonary tissue similar to that found in sequestration, but without systemic perfusion. Between the two there are six pathological processes (congenital lobar emphysema, bronchogenic cyst, congenital cystic adenomatoid malformation, hypogenetic lung syndrome, bronchopulmonary sequestration and pulmonary arteriovenous malformation) with a high degree of overlapping between them, rendering classification difficult and in some cases making it impossible to group the pathologic findings into a definite entity. The prototype of these anomalies is pulmonary sequestration, defined as a congenital pulmonary malformation in which there is a mass of nonfunctioning pulmonary tissue, unattached to the bronchial tree, per-
fused by systemic arteries. If the anomalous arteries perfuse normal pulmonary tissue, it is considered a different malformation, called isolated systemic supply to normal lung (ISSNL) [ 121. In ISSNL, patients are usually asymptomatic, although there may exist a continuous murmur on the thoracic wall or left ventricular growth and heart failure secondary to left-to-left shunt [ 111. Hemoptysis has occasionally been described, as in our second case [ 1.51. Associated diaphragmatic defects may occasionally be seen [2,9]. Chest radiography shows increased density in the affected lung. It is sometimes possible to recognize well-defined tubular or rounded images produced by the anomalous vessels. The pulmonary parenchyma does not present any other changes, apart from the exceptional cases of bleeding. Bronchoscopy and bronchography are normal. Aortography shows the systemic vessel arising from the aorta and perfusing the affected lung without direct communication between the systemic artery and the pulmonary vein. Pulmonary angiography shows a decrease in the calibre or absence of the pulmonary branches perfusing the anomalous zone. CT has been used successfully in the study of congenital pulmonary malformations [ 221. The only case of ISSNL studied by CT in the literature [ 151 did not include a detailed description of the findings. In our two cases, CT enabled a definitive diagnosis revealing the characteristic signs of ISSNL, a systemic artery and absence of pathology of the underlying lung. In other entities with systemic vascularization, namely pulmonary sequestration, the anomalous artery is identified by CT in only 40% of cases [22], perhaps due to the fact that pulmonary disease hampers visualization of the artery. Visualization of the anomalous vessel and its intrapulmonary pathway in ISSNL is probably facilitated by the absence of pulmonary involvement. The majority of cases of IS SNL appear to have a single artery with a thick calibre, probably yet another factor enabling easy identification by CT. Differential diagnosis with sequestration is possible as pulmonary involvement is always seen by CT in true sequestration [ 22-261. Differential diagnosis with other vascular malformations without parenchymatous involvement is not required as the AV malformation comes from the pulmonary artery, has an anomalous venous return and does not perfuse the pulmonary parenchyma. Although our findings need confirmation in further studies, we believe CT should be the initial method of study when ISSNL is suspected as it provides rapid, non-invasive identification of the systemic vascularization and demonstrates the absence of pulmonary involvement, both characteristic signs of this entity.
142
References 1 Pryce DM, Holmes Sellers T, Blair LG. Intralobar sequestration of lung associated with an abnormal pulmonary artery. Br J Surg 1947; 35: 18-29. 2 Cole FH, Alley FH, Jones. Aberrant systemic arteries to the lower lung. Surg Gynecol Obstet 1951: 93: 589-596. 3 Campbell DC, Murney JA, Dominy DE. Systemic arterial blood supply to a normal lung. JAMA 1962; 182: 497-499. 4 Painter RL, Billig DM, Epstein I. Anomalous systemic arterialization of the lung without sequestration. N Engl J Med 1968; 279: 866-867. 5 Scott LP, Perry LW. Systemic artery-pulmonary vein listulas. Am J Cardiol 1969; 23: 872-876. 6 Litwin SB, Plauth WH, Nadas AS. Anomalous systemic arterial supply to the lung causing pulmonary-artery hypertension. N Engl J Med 1970; 283: 1098-1099. 7 Hessel EA, Boyden EA, Stamm SJ, Sauvage LR. High systemic origin of the sole artery to the basal segments of the left lung: findings, surgical treatment, and embryologic interpretation. Surgery 1970; 67: 624-632. 8 Ennis JT, Moule NJ, Woo-Ming M. Intralobar pulmonary sequestration in association with bilateral systemic arterialization of the lungs. Br J Radio1 1972; 45: 945-948. 9 MacPherson RI, Whytehead L. Pseudosequestration. J Can Assoc Radio1 1977: 28: 17-25. 10 Currarino G, Willis K, Miller W. Congenital fistula between an aberrant systemic artery and a pulmonary vein without sequestration. J Pediatr 1975; 87: 554-557. 11 Levine MM, Nude1 DB, Gootman N, Wolpowitz A, Wisoff BG. Pulmonary sequestration causing congestive heart failure in infancy. Ann Thorac Surg 1982: 34: 581-585. 12 Kirks DR, Kane PE, Free EA, Taybi H. Systemic arterial supply to normal basilar segments ofthe left lower lobe. AJR 1976; 126: 817-821. 13 Ishihara Y, Fukuda R, Awaya Y et al. Anomalous systemic arterial supply to the basal segments of the lung presenting with a murmur. Eur J Pediatr 1979; 131: 125-131. 14 Makinen ED, Merikanto J, Rikalainen J, Satokari K. Intralobar
15
16
17 18
19 20
21
22
23
24
25 26
pulmonary sequestration without alteration of pulmonary parenchyma. Pediatr Radio1 1981; 10: 237-240. Flisak ME, Chorasekar AJ, Marsan RE, Mumtaz ALI M. Systemic arterialization of lung without sequestration. AJR 1982; 138: 751-753. Pryce DM. Lower accessory pulmonary artery with intralobar sequestration of lung: report of seven cases. J Path01 Bacterial 1946; 58: 457-461. Sade RM, Clouse M. Ellis FH. The spectrum of pulmonary sequestration. Ann Thorac Surg 1974; 18: 644-658. Zumbro GL, Treasure RL, Seitter G, Strevey TE, Brott W, Green DC. Pulmonary sequestration: a broad spectrum of bronchopuhnonary foregut abnormalities. AnnThorac Surg 1975; 20: 161-169. Flye MW, Conley M, Silver D. Spectrum of pulmonary sequestration. Ann Thorac Surg 1976; 22: 478-482. Clements BS, Warner JO. Pulmonary sequestration and related congenital bronchopulmonary-vascular malformations: nomenclature and classification based on anatomical and embryological considerations. Thorax 1987; 42: 401-408. Heitzman ER. Anomalies of pulmonary parenchymal and peripheral vascular development: the sequestration spectrum. In: Heitzman ER, ed. The lung. Radiologic-pathoIogic correlations, 2nd edn. St. Louis: Mosby Company, 1984; 17-19. Mata JM, Caceres J, Lucaya J, Garcia-Conesa JA. CT in congenital malformations of the lung. RadioGraphics 1990; 10: 65 l-674. Hochhauser L, Gray RR, St. Louis EL et al. Computed tomographic diagnosis of pulmonary sequestration. Comput Radio1 1983; 7: 295-299. Pedersen ML, Lequire MH, Spies JB, Lado WA. Computed tomography of intralobar bronchopulmonary sequestration supplied from the renal artery. J Comput Assist Tomogr 1988; 12: 874-875. Paul DJ, Mueller CF. Pulmonary sequestration. J Comput Assist Tomogr 1982; 6: 163-165. Miller PA, Williamson BRJ, Minor GR, Buschi AJ. Pulmonary sequestration: visualization of the feeding artery by CT. J Comput Assist Tomogr 1982; 6: 828-830.
