Current imaging of prenatally diagnosed congenital lung lesions

MRI and ultrasound fusion imaging for prenatal diagnosis

OBJECTIVE

A combination of magnetic resonance imaging (MRI) images with real time high-resolution ultrasound known as fusion imaging may improve prenatal examination. This study was undertaken to evaluate the feasibility of using fusion of MRI and ultrasound (US) in prenatal imaging.

STUDY DESIGN

This study was conducted in a tertiary referral center. All patients referred for prenatal MRI were offered to undergo fusion of MRI and US examination. All cases underwent 1.5 Tesla MRI protocol including at least 3 T2-weighted planes. The Digital Imaging and Communications in Medicine volume dataset was then loaded into the US system for manual registration of the live US image and fusion imaging examination.

RESULTS

Over the study period, 24 patients underwent fusion imaging at a median gestational age of 31 (range, 24-35) weeks. Data registration, matching and then volume navigation was feasible in all cases. Fusion imaging allowed superimposing MRI and US images therefore providing with real time imaging capabilities and high tissue contrast. It also allowed adding a real time Doppler signal on MRI images. Significant fetal movement required repeat-registration in 15 (60%) cases. The average duration of the overall additional scan with fusion imaging was 10 ± 5 minutes.

CONCLUSION

The combination of fetal real time MRI and US image fusion and navigation is feasible. Multimodality fusion imaging may enable easier and more extensive prenatal diagnosis.

The role of CT angiography in the evaluation of pediatric renovascular hypertension

Historically, the evaluation of renovascular hypertension has been accomplished by US, renal scintigraphy and digital subtraction angiography. Based on its high accuracy reported in adults renal CT angiography (CTA) with pediatric-appropriate low radiation dose techniques has become an important tool in the workup of renovascular hypertension in children. Renal CTA has several advantages over more conventional imaging modalities, including rapid and non-invasive acquisition, high resolution and easy reproducibility. Additionally, in our experience high-quality renal CTA can be performed using low-dose radiation exposures and can be acquired without sedation in most instances. This article illustrates by examples the usefulness of renal CTA for diagnosis of childhood renovascular hypertension and provides an overview of renal CTA findings in the most common childhood renovascular diseases.

Prenatal diagnosis of fetal unilateral lung agenesis complicated with cardiac malposition

BACKGROUND

Fetal unilateral lung agenesis, complicated with cardiac shifting, is a rare anomaly, the diagnosis of which remains a challenge for many sonographers in routine screening programs. The present study describes a systematic approach for the diagnosis of fetal unilateral lung agenesis and cardiac malpositions in routine prenatal screening.

METHODS

A total of 18 cases of fetal unilateral lung agenesis complicated with cardiac malposition were reviewed. A systematic method was proposed to identify the fetal left side and right side according to the fetal head position and posture by acquiring a long axis and transverse view of the fetus. Fetal unilateral lung agenesis was diagnosed by evaluation of the ipsilateral pulmonary artery. The diagnosis was confirmed by postnatal echocardiography, digital radiology, and computed tomography after birth or by autopsy findings.

RESULTS

The left-sided fetal heart with the cardiac apex rotating to the left and posterior were confirmed in all 7 left lung agenesis cases, while the rightward shifting of the fetal heart together with the cardiac axis deviating to the right were confirmed in all 11 cases of right lung agenesis. The disappearance of the ipsilateral pulmonary artery was confirmed in all 18 cases of unilateral lung agenesis. Cardiac anomalies were present in a total of 7 of the 18 cases of lung agenesis with 4 of 7 in cases of left lung agenesis and 3 of 11 in cases of right agenesis.

CONCLUSIONS

The systematic approach introduced in the current report is helpful in the diagnosis of fetal unilateral lung agenesis complicated with cardiac malposition. The information provided by this study may be helpful to better understand unilateral lung agenesis anatomically and to facilitate its potential examination.

Ultrasound of the pediatric chest

Historically, the evaluation of the pediatric chest has been accomplished via CT and conventional radiography. Our objective is to discuss and illustrate the role of US as a non-ionizing radiation alternative in the evaluation of the pediatric chest. US is a valuable tool in the evaluation of the pediatric chest. It can be used as a first-line modality in the evaluation of superficial lumps and bumps of the chest wall, diaphragmatic motion, the thymus and pleural effusions, and it can play a valuable secondary role in evaluation of mediastinal masses and pulmonary parenchymal disease.

Antenatal and postnatal management of congenital cystic adenomatoid malformation

Congenital thoracic malformations (CTMs) are a heterogeneous group of rare disorders that may involve the airways or lung parenchyma. The authors have focused on the condition that causes the most controversy, namely, congenital cystic adenomatoid malformation (CCAM). The reported incidence is 3.5 and 0.94 per 10,000 live births for CTMs and CCAMs respectively. Ultrasound is the antenatal imaging modality of choice for screening for CCAMs whilst magnetic resonance imaging is complimentary for morphological and volumetric evaluation of the foetal lung. Most CCAMs are detected antenatally with only a small proportion presenting postnatally. Only a few CCAMs cause foetal problems, with foetal hydrops being the best predictor of death. Although many CCAMs regress during pregnancy, most remain detectable postnatally by CT scans. Surgical excision of symptomatic lesions is relatively straightforward, but management of asymptomatic lesions is controversial. Some surgeons adopt a "wait and see" approach operating only on those patients who develop symptoms, but others operate on asymptomatic patients usually within the first year of life. Due to the potential of malignant transformation, children should have long term follow up. There is an urgent need to delineate the natural history of antenatally detected CCAMs to guide future management.

Intradiaphragmatic pulmonary sequestration: advantages of the thoracoscopic approach

Pulmonary sequestrations are accessory foregut lesions that are most commonly located within the thorax and occasionally in the abdominal cavity. Sequestrations arising within the diaphragm are exceedingly rare. We describe 2 patients found to have left peridiaphragmatic lesions on prenatal ultrasound and postnatal computed tomography. In the first patient, an initial laparoscopic approach was abandoned in favor of a thoracoscopic approach after no intraabdominal mass was found. The second patient had an uncomplicated thoracoscopic resection of a similar lesion. To our knowledge, these represent the first intradiaphragmatic pulmonary sequestrations to be resected via a minimally invasive approach. The rarity of these lesions makes definitive diagnosis without operative intervention challenging. Thoracoscopy appears to be a reasonable approach for resection of such intradiaphragmatic lesions.

[Congenital malformations of the lung, the radiologist's point of view]

Congenital lung malformations include a complex range of developmental abnormalities. Currently, most are diagnosed prenatally or during early childhood. They may, however, be discovered later, incidentally or in connection with non-specific symptoms, sometimes severe. Knowledge of their radiological appearances is necessary for their detection. Proper technique and analysis of cross-sectional imaging, computed tomography and magnetic resonance imaging, allow a definitive diagnosis in most patients and pre-treatment evaluation of surgical cases. This review will describe the radiological aspects of congenital pulmonary malformations, especially those which may occur in late childhood or adult life. When present, alternative diagnoses will be discussed. A distinction will be made between anomalies originating from bronchopulmonary structures, such as bronchial atresia, bronchogenic cyst, congenital lobar overinflation, cystic adenomatoid malformation, and forms related to vascular anomalies (vascular rings, anomalous left pulmonary artery, pulmonary underdevelopment, proximal interruption of the pulmonary artery, pulmonary sequestration, scimitar syndrome).

Complex communicating bronchopulmonary foregut malformation with pancreatic heterotopy depicted with fetal magnetic resonance imaging: a case report

Bronchopulmonary foregut malformation (BPFM) is a group of rare congenital anomalies that affect the respiratory and upper gastrointestinal tracts. We report here the first case of prenatal depiction of communicating BPFM, including extrapulmonary sequestration and foregut cyst, both with pancreatic differentiation. Magnetic resonance imaging on the fetus confirmed a polymalformative syndrome with right-lung and gastric cysts and allowed the detection of respiratory and alimentary tracts communication and aberrant feeding vessels. Diagnosis was confirmed after birth by multidetector computed tomography and postnatal pathologic findings. The patient, a boy, underwent surgery for respiratory distress at 4 weeks of life. This singular case confirms the benefits of early surgery for communicating BPFM.

Congenital cystic adenomatoid malformation: is there a need for pregnancy termination?

Aim. Congenital cystic adenomatoid lung malformation is a rare unilateral dysplasia of the lung. Three pathologic types are described in the literature: type I with cysts >2 cm, type II with cysts <1 cm, and type III with microcysts. The aim of this paper is to present a case of a fetus with congenital cystic adenomatoid lung malformation and discuss the necessity for pregnancy termination according to its prognosis and future mortality. Case. A 36-year-old pregnant woman (para: 1, gravida: 1) presented in our department for anatomy ultrasound screening at 20 + 1 weeks of gestation. The ultrasound detected a cystic adenomatoid right lung malformation measuring 1.45 × 1.67 cm which caused mediastinal shift of the heart and the lung to the left side. Other findings were cysts of the choroid plexus and echogenic intracardiac foci. The parents after genetic counseling decided pregnancy termination. The pregnant received cabergoline for ablactation. Conclusion. Congenital cystic adenomatoid lung malformation has different prognosis according to the type (69% in type I, 0% in types II and III). Fetal hydrops, cardiac and skeletal anomalies, Potter's syndrome, and gastrointestinal atresia are common cofindings. Genetic counseling is necessary, and pregnancy termination is proposed to the cases with poor prognosis.

Prenatal diagnosis of congenital lung malformations

Prenatal diagnosis of congenital lung anomalies has increased in recent years as imaging methods have benefitted from technical improvements. The purpose of this pictorial essay is to illustrate typical imaging findings of a wide spectrum of congenital lung anomalies on prenatal US and MRI. Moreover, we propose an algorithm based on imaging findings to facilitate the differential diagnosis, and suggest a follow-up algorithm during pregnancy and in the immediate postnatal period.

Imaging of fetal chest masses

Prenatal imaging with high-resolution US and rapid acquisition MRI plays a key role in the accurate diagnosis of congenital chest masses. Imaging has enhanced our understanding of the natural history of fetal lung masses, allowing for accurate prediction of outcome, parental counseling, and planning of pregnancy and newborn management. This paper will focus on congenital bronchopulmonary malformations, which account for the vast majority of primary lung masses in the fetus. In addition, anomalies that mimic masses and less common causes of lung masses will be discussed.

Fetal MRI for prediction of neonatal mortality following preterm premature rupture of the fetal membranes

BACKGROUND

Lung MRI volumetrics may be valuable for fetal assessment following early preterm premature rupture of the foetal membranes (pPROM).

OBJECTIVE

To evaluate the predictive value of MRI lung volumetrics after pPROM.

MATERIALS AND METHODS

Retrospective cohort study of 40 fetuses after pPROM in a large, tertiary, perinatal referral center. Fetuses underwent MRI lung volumetrics. Estimated lung volume was expressed as percentage of expected lung volume (our own normal references). Primary outcome was neonatal mortality due to respiratory distress before discharge from hospital.

RESULTS

Gestational age range was 16-27 weeks. Estimated-to-expected lung volume was 73% in non-survivors and 102% in survivors (P < 0.05). There were no survivors with a lung volume less than 60% of expected. By logistic regression, mortality could be predicted with a sensitivity of 80%, specificity of 86% and accuracy of 85%.

CONCLUSION

Fetal MR lung volumetrics may be useful for predicting mortality due to respiratory distress in children with early gestational pPROM.

Malformações pulmonares congênitas

As malformações congênitas do pulmão são raras e variam muito na sua forma de apresentação clínica e gravidade, dependendo principalmente do grau de envolvimento pulmonar e de sua localização na cavidade torácica. Elas podem se manifestar em qualquer idade e podem ser fonte de importante morbidade e mortalidade em lactentes e crianças. Os indivíduos com malformações congênitas do pulmão podem apresentar sintomas respiratórios ao nascimento, enquanto outros podem permanecer assintomáticos por longos períodos. Atualmente, com o uso rotineiro da ultrassonografia pré-natal, vem ocorrendo um aumento no diagnóstico mais precoce dessas malformações. A manifestação clínica dessas malformações varia desde uma disfunção respiratória pós-natal imediata a um achado acidental na radiografia de tórax. O diagnóstico precoce e o tratamento imediato oferecem a possibilidade de um desenvolvimento pulmonar absolutamente normal. Quando assintomáticos, a conduta para o tratamento dos pacientes com malformações pulmonares ainda é controversa, uma vez que o prognóstico dessas afecções é imprevisível. O manejo dessas lesões depende do tipo de malformação e de sintomas. Devido ao risco de complicação, a maioria dos autores sugere a ressecção da lesão no momento em que essa é identificada. A lobectomia é o procedimento de escolha, fornecendo excelentes resultados a longo prazo. Este artigo descreve as principais malformações pulmonares congênitas, seu diagnóstico e controvérsias quanto o tratamento.