Diagnostic value of chest CT combined with x-ray for premature infants with bronchopulmonary dysplasia

Improving early diagnosis of bronchopulmonary dysplasia

INTRODUCTION

Bronchopulmonary disease (BPD) is associated with long-term neurodevelopmental and cardiorespiratory complications, often requiring significant use of resources. To reduce this healthcare burden, it is essential that those at high risk of BPD are identified early so that strategies are introduced to prevent disease progression. Our aim was to discuss potential methods for improving early diagnosis in the first week after birth.

AREAS COVERED

A narrative review was undertaken. The search strategy involved searching PubMed, Embase and Cochrane databases from 1967 to 2024. The results of potential biomarkers and imaging modes are discussed. Furthermore, the value of scoring systems is explored.

EXPERT OPINION

BPD occurs as a result of disruption to pulmonary vascular and alveolar development, thus abnormal levels of factors regulating those processes are promising avenues to explore with regard to early detection of high-risk infants. Data from twin studies suggests genetic factors can be attributed to 82% of the observed difference in moderate to severe BPD, but large genome-wide studies have yielded conflicting results. Comparative studies are required to determine which biomarker or imaging mode may most accurately diagnose early BPD development. Models which include the most predictive factors should be evaluated going forward.

Imaging of bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is a multifactorial disease with many associated co-morbidities, responsible for most cases of chronic lung disease in childhood. The use of imaging exams is pivotal for the clinical care of BPD and the identification of candidates for experimental therapies and a closer follow-up. Imaging is also useful to improve communication with the family and objectively evaluate the clinical evolution of the patient's disease. BPD imaging has been classically performed using only chest X-rays, but several modern techniques are currently available, such as lung ultrasound, thoracic tomography, magnetic resonance imaging and electrical impedance tomography. These techniques are more accurate and provide clinically meaningful information. We reviewed the most recent evidence published in the last five years regarding these techniques and analyzed their advantages and disadvantages.

Early severity prediction of BPD for premature infants from chest X-ray images using deep learning: A study at the 28th day of oxygen inhalation

BACKGROUND AND OBJECTIVE

Bronchopulmonary dysplasia is a common respiratory disease in premature infants. The severity is diagnosed at the 56th day after birth or discharge by analyzing the clinical indicators, which may cause the delay of the best treatment opportunity. Thus, we proposed a deep learning-based method using chest X-ray images of the 28th day of oxygen inhalation for the early severity prediction of bronchopulmonary dysplasia in clinic.

METHODS

We first adopted a two-step lung field extraction method by combining digital image processing and human-computer interaction to form the one-to-one corresponding image and label. The designed XSEG-Net model was then trained for segmenting the chest X-ray images, with the results being used for the analysis of heart development and clinical severity. Therein, Six-Point cardiothoracic ratio measurement algorithm based on corner detection was designed for the analysis of heart development; and the transfer learning of deep convolutional neural network models were used for the early prediction of clinical severities.

RESULTS

The dice and cross-entropy loss value of the training of XSEG-Net network reached 0.9794 and 0.0146. The dice, volumetric overlap error, relative volume difference, precision, and recall were used to evaluate the trained model in testing set with the result being 98.43 ± 0.39%, 0.49 ± 0.35%, 0.49 ± 0.35%, 98.67 ± 0.40%, and 98.20 ± 0.47%, respectively. The errors between the Six-Point cardiothoracic ratio measurement method and the gold standard were 0.0122 ± 0.0084. The deep convolutional neural network model based on VGGNet had the promising prediction performance, with the accuracy, precision, sensitivity, specificity, and F1 score reaching 95.58 ± 0.48%, 95.61 ± 0.55%, 95.67 ± 0.44%, 96.98 ± 0.42%, and 95.61±0.48%, respectively.

CONCLUSIONS

These experimental results of the proposed methods in lung field segmentation, cardiothoracic ratio measurement and clinic severity prediction were better than previous methods, which proved that this method had great potential for clinical application.

Relationship between bronchopulmonary dysplasia phenotypes with high-resolution computed tomography score in early preterm infants

OBJECTIVE

To assess the relationship between high-resolution computed tomography (HRCT) abnormalities and clinical phenotypes of bronchopulmonary dysplasia (BPD).

METHODS

A retrospective, single-center study was carried out at the Children's Hospital of Fudan University between 2013 and 2020. Preterm infants born at ≤ 32 weeks' gestation who were diagnosed with BPD and had HRCT between 40 and 50 weeks postmenstrual age (PMA)were included in the study. HRCT images from six pulmonary lobes were scored based on seven types of pulmonary lesions from two categories: hyperaeration lesions and parenchymal lesions. The hyperaeration score (HS) included scores of decreased attenuation, mosaic attenuation, and bulla/bleb, while the parenchymal score (PS) included those of linear lesion, consolidation, bronchial wall thickening, and bronchiectasis. All seven scores were summed up to create the total score (TS). One-way ANOVA testing or Kruskal-Wallis testing was adopted for the comparison of HRCT scores with BPD severity and clinical phenotypes. The correlation between HRCT scores and clinical phenotypes was evaluated by Spearman's correlation analysis.

RESULTS

A total of 81 cases were included in the study. Cases with more severe BPD had a higher TS (p = 0.01), HS (p = 0.02), PS (p = 0.02), mosaic attenuation score (p = 0.03), bulla/Bleb score (p = 0.03), and linear density score (p = 0.01). TS (r = 0.28), PS (r = 0.35), linear density (r = 0.34), and consolidation (r = 0.24) were correlated with pulmonary hypertension (PH). However, no HRCT score was significantly different between the patients with or without tracheobronchomalacia (TBM). BPD patients with a combination of lung parenchymal disease, PH, and TBM had the highest TS and HS.

CONCLUSION

HRCT scores correlated with BPD severity and PH in our study. HS might be a useful tool in the assessment of BPD severity while linear densities and consolidation might be helpful in predicting PH.

Lung growth and pulmonary function after prematurity and bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) still carries a heavy burden of morbidity and mortality in survivors of extreme prematurity. The disease is characterized by simplification of the alveolar structure, involving a smaller number of enlarged alveoli due to decreased septation and a dysmorphic pulmonary microvessel growth. These changes lead to persistent abnormalities mainly affecting the smaller airways, lung parenchyma, and pulmonary vasculature, which can be assessed with lung function tests and imaging techniques. Several longitudinal lung function studies have demonstrated that most preterm-born subjects with BPD embark on a low lung function trajectory, never achieving their full airway growth potential. They are consequently at higher risk of developing a chronic obstructive pulmonary disease-like phenotype later in life. Studies based on computer tomography and magnetic resonance imaging, have also shown that in these patients there is a persistence of lung abnormalities like emphysematous areas, bronchial wall thickening, interstitial opacities, and mosaic lung attenuation also in adult age. This review aims to outline the current knowledge of pulmonary and vascular growth in survivors of BPD and the evidence of their lung function and imaging up to adulthood.

Lung ultrasound predicts the development of bronchopulmonary dysplasia: a prospective observational diagnostic accuracy study

This study aimed to evaluate the predictive ability of lung ultrasound (LU) in the development of bronchopulmonary dysplasia (BPD) in very low birth weight (VLBW) infants. A total of 130 VLBW infants with gestational age < 32 weeks were included; LU was performed at days 1, 2, 3, 6, 9, 12, and 15 postnatally. We calculated the LU score by 12-region, 10-region, and 6-region protocols. The incidence of BPD according to the National Institutes of Health (NIH) 2001 definition and 2019 criteria was 38.5% and 64.6%, respectively. By 12-region and 10-region protocols, LU predicted BPD from the 9^th to 15^th days of life (DOLs) regardless of the criteria used, with an area under the curve (AUC) ranging from 0.826 (95% confidence interval (CI): 0.750-0.887) to 0.877 (95% CI: 0.807-0.928). According to the 2019 BPD definition, the LU score incorporated gestational age, and invasive mechanical ventilation >6 days predicted BPD on the 6^th DOL with an AUC of 0.862 (95% CI: 0.790-0.916). The 6-region protocol had significantly smaller AUC values on the 6^th and 9^th DOLs than the other two protocols.Conclusion: The 12-region and 10-region LU scoring protocols are superior to the 6-region protocol in the prediction of BPD. LU can predict the development of BPD from the 9^th to 15^th DOLs. With the addition of clinical variables, the earliest prediction time was the 6^th DOL. What is Known: • Bronchopulmonary dysplasia is the most common and adverse complication of prematurity. Recent four studies found that lung ultrasound score or findings predicted the development of bronchopulmonary dysplasia. What is New: • We present analysis by classical 6-region and the other two lung ultrasound score (10-region and 12-region) which include an assessment of the posterior lung to allow to understand what is the best score to be used. In addition, we explore whether LU-incorporated clinical variables could improve the predictive value for BPD.

Clinical Characteristics and Outcomes Until 2 Years of Age in Preterm Infants With Typical Chest Imaging Findings of Bronchopulmonary Dysplasia: A Propensity Score Analysis

Objective: The goal of the current study was to assess the associations of typical chest imaging findings of bronchopulmonary dysplasia (BPD) in preterm infants with clinical characteristics and outcomes until 2 years of age. Method: This retrospective cohort study enrolled 256 preterm infants with BPD who were admitted between 2014 and 2018. A propensity score analysis was used to adjust for confounding factors. The primary outcomes were the severity of BPD, home oxygen therapy (HOT) at discharge and mortality between 28 days after birth and 2 years of age. A multivariate logistic regression analysis was performed to identify related variables of mortality. Results: Seventy-eight patients with typical chest imaging findings were enrolled, of which 50 (64.1%) were first found by CXR, while 28 (35.9%) were first found by CT. In addition, 85.9% (67/78) were discovered before 36 weeks postmenstrual age (PMA) (gestational age [GA] < 32 weeks) or before 56 days after birth (GA > 32 weeks). After propensity score matching, the matched groups consisted of 58 pairs of patients. Those with typical imaging findings had a remarkably higher mortality rate (29.3 vs. 12.1%, p = 0.022, OR 3.021), higher proportion of severe BPD (32.8 vs. 12.1%, p = 0.003, OR 4.669) and higher rate of HOT at discharge (74.1 vs. 46.6%, p = 0.002, OR 3.291) than those without typical imaging findings. The multivariate logistic regression analysis showed that typical imaging findings ≤ 7 days and typical typical imaging findings >7 days were independent risk factors for mortality in preterm infants with BPD (OR 7.794, p = 0.004; OR 4.533, p = 0.001). Conclusions: More attention should be given to chest imaging findings of BPD, especially in the early stage (within 7 days). Early recognition of the development of BPD helps early individualized treatment of BPD. Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT04163822.

Lung Ultrasonography to Diagnose Bronchopulmonary Dysplasia of Premature Infants

Background: Bronchopulmonary dysplasia (BPD) is a common severe respiratory problem in premature infants, and imaging information has important reference value for its diagnosis. Recently, lung ultrasonography (LUS) has been successfully used for the diagnosis and differential diagnosis of neonatal lung diseases (NLDs), but the study of the diagnosis of BPD is still rare. Objectives: The purpose of this study was to investigate the ultrasonographic characteristics of BPD and its value for the diagnosis and differential diagnosis of premature infants’ BPD. Methods: From January 2015 to December 2019, 25 premature infants diagnosed with early-stage BPD and 32 infants diagnosed with late-stage BPD according to their medical history, clinical manifestation, and chest X-ray were included in this study. The LUS examinations were performed on each infant. The LUS findings were recorded and compared with those of 40 premature infants without lung diseases. Results: The gestational age of 25 early-stage BPD infants was 26+1 – 31+6 weeks, and their birth weight was between 730 and 1,810 g. The gestational age of 32 late-stage BPD infants was 26 - 32 weeks, and their birth weight was 750 - 1,760 g. The gestational age of 40 control infants was 25+6 - 32+1 weeks, and their birth weight was 810 - 2,050 g. There was no difference in the proportion of primary lung diseases (including RDS, TTN, pneumonia, etc.) between the three groups. The proportions of infants receiving invasive and/or non-invasive respiratory support at admission in the three groups of early BPD, late BPD, and normal control were 20/25 (80.0%), 26/32 (81.2%), and 33/40 (77.5%), respectively, with no significant difference (P > 0.05). The mechanical ventilation duration over one week in three groups was 15/20 (75%), 21/26 (80.7%), and 24/33 (72.7%), respectively, with no significant difference (P > 0.05). Nonspecific pleural line abnormalities were seen in all early and late BPD patients (100%), alveolar-interstitial syndrome (AIS) in 16 cases (64%) of early BPD and 32 cases of late BPD infants (100%), pleural insect erosion-like change (PIE-like change) in two cases of early-stage BPD infants (8.0%) and 20 cases (62.5%) of late-stage BPD infants, and air vesicle signs (AVS) only in 17 cases of late-stage BPD infants. The sensitivity and specificity of PIE-like change for the diagnosis of late-stage BPD were 62.5% and 92.0%, respectively, and the sensitivity and specificity of AVS for the diagnosis of late-stage BPD were 53.1 and 100%, respectively. Conclusions: Lung ultrasonography is not specific for the diagnosis of early-stage BPD, but has a high reference value and specificity for the diagnosis of late-stage BPD when combined with obvious pulmonary fibrosis and pulmonary vesicle formation, which is mainly manifested by AIS, PIE-like change, and AVS.

Pediatric Pulmonary Hypertension: Definitions, Mechanisms, Diagnosis, and Treatment

Pediatric pulmonary hypertension (PPH) is a multifactorial disease with diverse etiologies and presenting features. Pulmonary hypertension (PH), defined as elevated pulmonary artery pressure, is the presenting feature for several pulmonary vascular diseases. It is often a hidden component of other lung diseases, such as cystic fibrosis and bronchopulmonary dysplasia. Alterations in lung development and genetic conditions are an important contributor to pediatric pulmonary hypertensive disease, which is a distinct entity from adult PH. Many of the causes of pediatric PH have prenatal onset with altered lung development due to maternal and fetal conditions. Since lung growth is altered in several conditions that lead to PPH, therapy for PPH includes both pulmonary vasodilators and strategies to restore lung growth. These strategies include optimal alveolar recruitment, maintaining physiologic blood gas tension, nutritional support, and addressing contributing factors, such as airway disease and gastroesophageal reflux. The outcome for infants and children with PH is highly variable and largely dependent on the underlying cause. The best outcomes are for neonates with persistent pulmonary hypertension (PPHN) and reversible lung diseases, while some genetic conditions such as alveolar capillary dysplasia are lethal. © 2021 American Physiological Society. Compr Physiol 11:2135-2190, 2021.