Anatomical associations and radiological characteristics of Scimitar syndrome on CT and MR

PurposeTo report the anatomical associations and radiological characteristics of Scimitar syndrome on CT and MR.Materials and methodsRetrospective review of the medical records between February 2001 and February 2016 was performed. To identify patients, radiological reports were queried for “Scimitar” or “partial anomalous pulmonary venous return.” Patients with radiological findings of Scimitar syndrome were included. Patients without cross-sectional imaging were excluded. Patients' demographics, radiologic images, and medical notes were reviewed. Two radiologists re-read the available imaging studies. Images were reviewed for Scimitar syndrome confirmation, number and location of Scimitar vein drainage, number of lobes drained by the Scimitar vein, and right pulmonary artery and lung hypoplasia. In addition, the number of pulmonary veins draining into the left atrium, left sided anomalous pulmonary veins, congenital heart disease, aortic arch anomalies, cardiac dextroposition, right ventricular enlargement, pulmonary artery enlargement, and elevated QP:QS ratios were identified. Other associated anomalies including the presence of an anomalous feeding artery and pulmonary sequestration, abnormal lobar pattern, localized bronchiectasis, horseshoe lung, accessory diaphragm, diaphragmatic hernia, vertebral anomalies, and genitourinary tract anomalies were reviewed.ResultsSixteen patients (3 males, 13 females; mean age 39.5 years, range 14 days–72 years) with confirmed Scimitar syndrome on CT and MR imaging were identified. The Scimitar vein drained to the infra-diaphragmatic inferior vena cava (IVC) in ten patients and to the supra-diaphragmatic IVC in six patients. The most common associated anomalies were right ventricle enlargement (93.3%), variant lobar pattern of the right lung (92.9%), enlarged pulmonary arteries (60%), and cardiac dextroposition (50%).ConclusionRecognizing the radiologic characteristics and anatomical associations of Scimitar syndrome is important as features of the primary condition and associated anomalies may have implications in surgical management.     

Scimitar syndrome – An incidental diagnosis in a case of fibroadenoma

Scimitar syndrome is a rare congenital anomaly which is characterised by anomalous pulmonary venous drainage of the either entire right lung or part of it into the inferior vena cava or portal vein or hepatic vein or right atrium occasionally. This can be associated with hypoplasia of the right lung, dextroposition, underdevelopment of right pulmonary artery and anomalous systemic arterial supply from the descending aorta to the hypoplastic lung. A 36 year old female came with history of swelling in the right breast which turned up to be right breast fibroadenoma. Routine chest radiograph revealed scimitar syndrome which was confirmed on CECT chest.     

Role of multi slice computed tomography in the evaluation of congenital anomalies of tracheobronchial tree and lungs

ObjectiveTo evaluate the role of MSCT in the evaluation of congenital anomalies of tracheobronchial tree and lungPatients and methodsTwenty nine patients with congenital anomalies of tracheobronchial tree and lung were examined using four and six MDCT.ResultsSeven patients (24%) had congenital cystic adenomatoid malformation where successful differentiation of the type was possible. Three patients (10.3%) with bronchopulmonary sequestration were categorized as two (7%) intralobar and one (3.5%) extralobar sequestrations. Four patients (14%) had congenital lobar overinflation. Four patients had Scimitar syndrome with right pulmonary artery hypoplasia, right sided lung hypoplasia, anomalous arterial supply and anomalous pulmonary venous drainage together with pulmonary hypertension. Abnormal bronchial anatomy was revealed in two patients with pulmonary isomerism and one patient with situs inversus. Bronchogenic cyst, tracheal bronchus, Kertagner's syndrome, pulmonary agenesis and horse shoe lung were seen in one patient each. Dynamic MSCT shows the lunate configuration of the trachea during forced expiration in one patient with tracheomalacia. In one patient with tracheo-esophageal fistula, the extent of fistulous tract and the resulting bronchial aspiration were demonstrated.ConclusionMSCT proved to be indispensable as a preoperative planning modality and an essential investigation for congenital anomalies of the lung and tracheobronchial tree.     

Scimitar syndrome: confirmation of diagnosis by a noninvasive technique (MRI)

Scimitar syndrome is a rare congenital pulmonary anomaly that is characterized by hypoplasia of the right lung and the right pulmonary artery with anomalous pulmonary venous drainage to the inferior vena cava or the right atrium. Very few reports are available that analyze the value of magnetic resonance imaging (MRI) in establishing the diagnosis. We present a case with Scimitar syndrome in which anomalous pulmonary venous return was confirmed by cine MRI.     

Anomalous systemic venous drainage occurring in association with the hypogenetic lung syndrome

A case in which anomalous systemic venous drainage occurred in association with the hypogenetic lung syndrome (scimitar syndrome) is described. The chest radiograph appearances of the anomalous systemic vein mimicked an anomalous pulmonary or scimitar vein. Angiography demonstrated that the patient also had a small anomalous pulmonary vein draining and a systemic artery supplying, the right lung. As the right lung was hypoplastic, all three features of the hypogenetic lung syndrome were present, in addition to partial anomalous systemic venous drainage.     

Embolization of the Systemic Arterial Supply via a Detachable Silicon Balloon in a Child with Scimitar Syndrome

Scimitar syndrome is a rare congenital disorder. It is characterized by partial or total abnormal venous drainage of the right lung into the inferior vena cava, which is often associated with anomalous systemic arterial supply to the right lung, congenital cardiac anomalies, hypoplasia of the right lung and bronchial anomalies. Symptoms depend on the degree of the shunt and severity of the associated anomalies, which determine the treatment. We present a 6-year-old boy who was diagnosed as having the adult form of scimitar syndrome during evaluation for recurrent pulmonary infections, and underwent embolization with a detachable silicon balloon of the anomalous systemic arterial supply from the abdominal aorta to the right lower lung lobe. Successful elective surgery was performed 6 months later, in which right pulmonary veins were directed to the left atrium using a Gore-Tex patch by creating an intra-atrial tunnel. The patient has been symptom-free period during 6 months of follow-up, which supports the idea that recurrent pulmonary infections can be eliminated by embolization of the anomalous arterial supply.     

24例镰刀综合征心血管造影征象分析

笔者分析了２４例镰刀综合征心肺血管病变的造影征象及其病理生理意义，并与手术（１４例）和尸解（４例）资料对照。２４例心血管造影示全部或部分右肺静脉异常引流，分别为１７例和７例。异常引流静脉近端局限性狭窄９例，其中２例异常和正常引流静脉间有侧支吻合，右下肺异常体动脉侧支供血１８例。并存各种心脏病变者１８例，马蹄肺６例，右下肺肺隔离症３例，下腔静脉闭锁和狭窄分别为２和１例。右下肺异常体动脉侧支和心脏病变是患者严重症状和肺动脉高压的主要因素。除肺隔离症外，经导管栓塞异常体动脉侧支可使用者明显受益。异常引流静脉狭窄具有限制血液分流的作用。     

Scimitar syndrome associated with gallbladder duplication

Scimitar syndrome is a rare congenital anomaly associated with the venous drainage of the lung to the inferior vena cava through a systemic vein. Chest radiography of an asymptomatic patient, aged 36, showed a linear opacity extending from the pulmonary hilum to the diaphragm, on the right chest (Scimitar sign). Computerized tomography of the thorax exposed that the cause of that image was Scimitar vein. Abdominal ultrasonography revealed duplication in the gallbladder. The literature holds no reports of an association between Scimitar syndrome and gallbladder duplication. Secondary gastrointestinal malformations can also be found in patients suffering from this syndrome.     

Partial anomalous pulmonary venous return in Turner syndrome

PurposeThe aim of this study is to describe the prevalence, anatomy, associations and clinical impact of partial anomalous pulmonary venous return in patients with Turner syndrome.Methods and resultsAll Turner patients who presented at our Turner clinic, between January 2007 and October 2015 were included in this study and underwent ECG, echocardiography and advanced imaging such as cardiac magnetic resonance or computed tomography as part of their regular clinical workup. All imaging was re-evaluated and detailed anatomy was described. Partial anomalous pulmonary venous return was diagnosed in 24 (25%) out of 96 Turner patients included and 14 (58%) of these 24 partial anomalous pulmonary venous return had not been reported previously. Right atrial or ventricular dilatation was present in 11 (46%) of 24 partial anomalous pulmonary venous return patients.ConclusionWhen studied with advanced imaging modalities and looked for with specific attention, PAPVR is found in 1 out of 4 Turner patients. Half of these patients had right atrial and/or ventricular dilatation. Evaluation of pulmonary venous return should be included in the standard protocol in all Turner patients.     

Remodelado cardíaco inverso en pacientes con hipertensión pulmonar tras trasplante bipulmonar. Estudio con tomografía computarizada multidetector

ObjectiveTo use multidetector computed tomography (MDCT) to evaluate the structural changes in the right heart and pulmonary arteries that occur in patients with severe pulmonary hypertension treated by double lung transplantation.Material and methodsThis was a retrospective study of 21 consecutive patients diagnosed with severe pulmonary hypertension who underwent double lung transplantation at our center between 2010 and 2014. We analyzed the last MDCT study done before lung transplantation and the first MDCT study done after lung transplantation. We recorded the following variables: diameter of the pulmonary artery trunk, ratio of the diameter of the pulmonary artery trunk to the diameter of the ascending aorta, diameter of the right ventricle, ratio of the diameter of the left ventricle to the diameter of the right ventricle, and eccentricity index. Statistical analysis consisted of the comparison of the means of the variables recorded.ResultsIn all cases analyzed, the MDCT study done a mean of 24 ± 14 days after double lung transplantation showed a significant reduction in the size of the right heart chambers, with improved indices of ventricular interdependency index, and reduction in the size of the pulmonary artery trunk (p < 0.001 for all the variables analyzed).ConclusionPatients with pulmonary hypertension treated by double lung transplantation present early reverse remodeling of the changes in the structures of the right heart and pulmonary arterial tree. MDCT is useful for detecting these changes.     

3D multidetector CT angiographic evaluation of extralobar pulmonary sequestration with anomalous venous drainage into the left internal mammary vein in a paediatric patient

Pulmonary sequestration is a congenital lung malformation, defined by dysplastic and non-functioning lung tissue lacking normal tracheobronchial connections and accompanied by an anomalous systemic blood supply. Recognition of anomalous arteries and veins in pulmonary sequestration is paramount to making the correct diagnosis. In contrast to intralobar pulmonary sequestration, where anomalous venous drainage is usually into the pulmonary venous system, the pattern of anomalous venous drainage is more varied in extralobar pulmonary sequestration. To the best of our knowledge, anomalous venous drainage to the internal mammary vein in extralobar sequestrations has not been reported. We report an anomalous venous drainage into the internal mammary vein in an extralobar sequestration which was evaluated with 3D multidetector CT angiography.     

Horseshoe lung: clinical, pathologic, and radiologic features and a new plain film finding

Horseshoe lung is a rare congenital malformation in which an isthmus of pulmonary parenchyma extends from the right lung base across the midline behind the pericardium and fuses with the base of the left lung. Six cases are presented and eight previously published case reports are reviewed. Eleven of these 14 cases occur in conjunction with scimitar syndrome, the complex of anomalies including hypoplasia of the right lung, anomalous right pulmonary venous return, and anomalous arterial supply to the right lung. Differentiation of scimitar syndrome from horseshoe lung can be made on the plain chest film, if, in addition to the typical radiographic findings of scimitar syndrome, there is evidence of a fine linear density in the medial aspect of the left base representing the lateral extent of the pulmonary isthmus. Recognition of horseshoe lung is important because children present in the first few years of life with significant respiratory symptoms, whereas the scimitar syndrome alone is usually discovered fortuitously after the first decade of life.     

Scimitar etcetera--the dysmorphic right lung

'Dysmorphic lung' is introduced as a term to describe any complex congenital malformation which involves both abnormal vascular morphology and disordered growth of a whole lung. The major group within this definition is the scimitar syndrome, which we choose to mean a hypoplastic lung with anomalous venous drainage and various degrees of collateral arterial supply. Nine typical cases of scimitar are presented, with three closely related cases. Six other cases of dysmorphic lungs are also present. The relationships between the groups are discussed, and an effort is made to clarify the nomenclature used in this condition.     

Normal pulmonary venous anatomy and non-anomalous variations demonstrated on CT angiography: what the radiologist needs to know?

Variations in pulmonary venous anatomy (in the absence of any anomalous pulmonary venous connections) is not uncommon. Commonly occurring variations include presence of conjoined pulmonary veins (PV), supernumerary PVs and ostial PVs. Variant PV anatomy is often asymptomatic; however, it may assume importance in the pre-procedural planning prior to cardiothoracic surgeries and radiofrequency catheter-directed ablation for PV isolation. It is therefore important that the radiologist is aware of the conventional normal and variant PV anatomy in addition to obvious abnormalities like anomalous PV drainage or PV stenosis/ occlusion. Multidetector CT (MDCT) is often used as the first-line imaging modality for pre-procedural PV mapping as it provides high quality images with short acquisition times and availability of numerous post-processing tools.This pictorial review focusses on the MDCT-based PV imaging describing the reporting nomenclature, the conventional normal as well as non-anomalous variant PV anatomy along with their clinical significance.     

MRI of partial anomalous pulmonary venous return (scimitar syndrome)

We report a case of anomalous pulmonary venous drainage into the inferior vena cava (scimitar syndrome). Cine MRI and 3-D contrast-enhanced MR angiography provides an non-invasive diagnostic technique in the evaluation of anomalous pulmonary venous return.     

Scimitar syndrome: morphological diagnosis and assessment of hemodynamic significance by magnetic resonance imaging

Scimitar syndrome has a variable presentation depending on the age at which the diagnosis is made. We report a case of a young woman (age 18 years) with suspected right pulmonary hypoplasia in whom a scimitar syndrome was diagnosed. Using MRI morphological findings and hemodynamic significance of the syndrome were assessed. Left-to-right shunt was calculated from blood flow measurements performed in the ascending aorta, the main pulmonary artery, and the aberrant scimitar vein.

     

Reliability of MDCT in characterizing pulmonary venous drainage, diameter and distance to first bifurcation: an interobserver study

RATIONALE AND OBJECTIVES: To evaluate the interobserver agreement of readers in evaluating pulmonary venous anatomy and in measuring pulmonary vein ostial diameters and distance to first bifurcation. MATERIALS AND METHODS: This study was approved by our institutional review board. Thin-section contrast material-enhanced multidetector computed tomography examinations of the thorax were retrospectively reviewed in 200 consecutive patients (38 females and 162 males), age 24-79 years (mean, 52.8) referred for imaging before radiofrequency ablation therapy for atrial fibrillation. For each patient, pulmonary venous anatomy and drainage patterns including the number of venous ostia was assessed independently by experienced cardiothoracic radiologists. Pulmonary vein ostial diameter and distance to the first bifurcation of the four major pulmonary veins (right inferior and superior, left inferior and superior), the middle lobe pulmonary vein, and any anomalous pulmonary veins (common trunks and accessory veins) were measured independently at a workstation. Interreader assessment of pulmonary venous anatomy was evaluated using the Kappa statistic. Interreader variation in measurements of venous diameter and distant to first bifurcation were estimated by Bland-Altman plots and Pitman's test of difference in variance. RESULTS: Very good to excellent interreader agreement in detection of anomalous pulmonary venous anatomy, middle lobe pulmonary venous drainage, and other thoracic venous anomalies. No significant variation between readers in pulmonary vein ostial diameter measurements for the four major and middle lobe pulmonary veins, or the anomalous pulmonary veins. Significant interreader variability was noted in measurements of the pulmonary vein distance to first bifurcation for the right inferior (P = .017), middle lobe (P = .005), and left inferior (P = .015) pulmonary veins. CONCLUSIONS: There is excellent interobserver agreement when evaluating normal and anomalous pulmonary venous drainage patterns, and when measuring normal or anomalous pulmonary vein diameters. However, measurements of distances to first bifurcation were less reliable across readers.     

Uncommon congenital extracardiac vascular anomalies detected on MSCT (Multi-Slice Computed Tomography) aortic angiography with 64-multislice technology

Objective

The purpose of this study was to evaluate the role of CT angiography in different encountered congenital vascular anomalies of pediatric age groups using 64 multislice CT scanner.

Subjective and methods

Through one year, a total of 15 patients having congenital extracardiac anomalies were encountered from those attending big trauma and emergency center and were studied in this work. Each patient’s parent was thoroughly asked about the detailed clinical history after reviewing the referring imaging request and laboratory findings. Exclusion criteria for CT were as follows: previous allergic reactions to iodine contrast media and severe renal insufficiency. CT examination was performed using 64 multislice CT machine.

Results

CTA examination was performed in a total of 15 patients. The age of the patients was ranging from 2 days to 14 yrs and 5 cases were females. Four cases came with cyanosis; one case came with follow up after operation for transposition of great arteries, while the remaining cases were suffering from medical problems such as respiratory distress or hypertension. Aortic arch hypoplasia, right sided aortic arch with mirror image or with aberrant left subclavian artery, hypoplastic left pulmonary artery with left sided aortic arch and aberrant right subclavian artery, hypoplastic left heart chambers, retrotracheal left pulmonary artery with patent ductus arteriosus (PDA), right superior partial anomalous pulmonary venous drainage (PAPVD) with ASD sinus venosum, postoperative assessment of transposition of great arteries (TGA), fibromuscular dysplasia involving the renal and common iliac arteries, and bilateral double renal arteries with ectopic right kidney were the different extracardiac vascular anomalies encountered in this work.

Conclusion

CTA provides an excellent means to detect a number of extracardiac vascular anomalies and allows accurate and fast noninvasive characterization of extracardiac vascular anatomy. It is a helpful tool in establishing the primary diagnosis, defining anatomic landmarks and relationships, identifying vascular anomalies and helping in postoperative follow-up.     

Acquired anomalous intrapulmonary venous connection secondary to pulmonary venous stenosis

An unusual case of acquired development of anomalous intrapulmonary venous connection with pulmonary venous stenosis is presented. Appearances on a chest radiograph resembled the "scimitar" sign in a patient with previous surgery for partial anomalous pulmonary venous return. Spiral CT and pulmonary arteriography showed stenosis of the right upper pulmonary vein and an anomalous intrapulmonary venous connection between the right upper pulmonary vein and the right lower pulmonary vein. We consider the slow progression of pulmonary vein stenosis led to anomalous intrapulmonary venous connection as an intrapulmonary collateral.     

Normative analysis of pulmonary vein drainage patterns on multidetector CT with measurements of pulmonary vein ostial diameter and distance to first bifurcation

RATIONALE AND OBJECTIVES: To document the frequency of normal and anomalous drainage patterns of the pulmonary veins, and to establish normal values for pulmonary vein ostial diameters, and distance to first bifurcation using multidetector computed tomography, as pertinent to ablation procedures for atrial fibrillation. MATERIALS AND METHODS: Two cardiothoracic radiologists retrospectively reviewed thin-section contrast material-enhanced multidetector computed tomography examinations of the thorax in 200 consecutive patients (38 females and 162 males), age 24-79 years (mean 52.8) referred for imaging before radiofrequency ablation therapy for atrial fibrillation. Pulmonary vein anatomy was based on both the number of venous ostia and the drainage patterns of pulmonary veins. Pulmonary vein ostial diameters and distance to first bifurcation of the four major pulmonary veins (right inferior and superior, left inferior and superior) and any additional pulmonary veins were measured at a workstation using both axial images and multiplanar reconstructions by two experienced cardiothoracic radiologists; the mean pulmonary vein diameter and the shortest distance to first bifurcation of the two measurements are reported. RESULTS: The majority of patients, 82% (164 patients) had four pulmonary veins, with a superior and inferior ostium on the right and a superior and inferior ostium on the left. Of the remainder, 9% (18 patients) had five veins, 4.5% (9 patients) had three veins, 3% (6 patients) had two anomalies each, and 0.5% (1 patient) had three anomalies. The middle lobe pulmonary vein drained into the right superior pulmonary vein in 83.5% of patients, directly into the left atrium in 11% of patients, and into the right inferior pulmonary vein in 5.5% of patients; 6.5% of patients had a single left pulmonary vein ostium. Mean pulmonary vein diameters with 95% confidence intervals at the ostia were as follows: right superior 17.6 (13.64-15.36) mm; left superior 16.6 (16.03-17.08) mm; right inferior 17.1 (16.58-17.55) mm; left inferior 14.8 (14.25-15.27) mm, and independent middle lobe 8.6 (8.27-8.86) mm. Mean distance to first bifurcation with 95% confidence intervals were: right superior 14.5 (17.02-18.23) mm; left superior 17.6 (16.63-18.53) mm; right inferior 7.0 (6.49-7.46) mm; left inferior 13.5 (12.83-14.16) mm, and independent middle lobe 8.4 (7.7-9.17) mm. CONCLUSION: Thin-section thoracic computed tomography demonstrates a greater variability of pulmonary venous drainage than previously described. There is greater variability of the right lung venous drainage compared to the left lung. Eighty-two percent of people have four standard pulmonary veins. There is significant variability in pulmonary vein diameter and distance to first bifurcation.