Congenital lung abnormality quantification by computed tomography: The CLAQ method

Imaging Diagnosis for Intradiaphragmatic Pulmonary Sequestration: A Pilot Study

OBJECTIVES

Extrapulmonary sequestration (EPS) within the diaphragm (ID-EPS) is rare and requires additional procedures such as incision or detachment of the diaphragm from the lesion for diagnosis. This study aimed to describe the imaging findings and evaluate the diagnostic accuracy of ultrasonography and computed tomography (CT) for ID-EPS.

MATERIAL AND METHODS

Split diaphragm sign, shape of lesion edge, drainage vein into intra-abdomen on ultrasound and CT, and lesion characteristics on ultrasound were compared between patients with ID-EPS and with above-diaphragm EPS (AD-EPS) using Fisher's exact test.

RESULTS

Three and nine patients were diagnosed with ID-EPS and AD-EPS, respectively. Significant differences were observed between the two groups in the split diaphragm sign on ultrasound (presence/absence in patients with ID-EPS vs AD-EPS, 2/1 vs 0/9, P = .046), shape of lesion edge on ultrasound/CT (round/beak in patients with ID-EPS vs AD-EPS, 3/0 vs 0/9, P = .005 on both CT and ultrasound), lesion characteristics on ultrasound (presence/absence of cystic area within lesion in patients with ID-EPS vs AD-EPS, 0/3 vs 7/2, P = .046), and the drainage vein into the abdomen on CT (presence/absence in patients with ID-EPS vs AD-EPS; 2/1 vs 0/9, P = .046). No drainage veins were visualized in the abdomen on ultrasonography and no significant differences in the presence/absence of the split-diagram sign on CT (presence/absence in patients with ID-EPS vs AD-EPS and ID-EPS; 0/3 vs 0/9, P > .999; 1/2 vs 0/9, P = .250) were observed between the two groups.

CONCLUSION

A combination of postnatal ultrasonography and CT was useful in predicting EPS located within the diaphragm.

The impact of undergoing elective pediatric lung resection during respiratory syncytial virus peak season on patient outcomes: A nationwide retrospective analysis

OBJECTIVES

Observational data to support delaying elective pediatric thoracic surgery during peak respiratory viral illness season is lacking. This study evaluated whether lung surgery during peak viral season is associated with differences in postoperative outcomes and resource utilization.

METHODS

A retrospective observational cohort study was performed using the Pediatric Health Information System (PHIS). Patients with a congenital lung malformation (CLM) who underwent elective lung resection between 1 January 2016 and 29 February 2020 were included. Respiratory syncytial virus (RSV) incidence was used as a proxy for respiratory viral illness circulation. Monthly hospital-specific RSV incidence was calculated from PHIS data, and peak RSV season was defined by Centers for Disease Control data. Multivariable regression models were built to identify predictors of postoperative mechanical ventilation, which was the main outcome measure, as well as secondary outcomes including 30-day readmission after lung resection, postoperative length of stay (LOS) and hospital billing charges.

RESULTS

Of 1542 CLM patients identified, 344 (22.3%) underwent lung resection during peak RSV season. 38% fewer operations were performed per month during peak RSV season than during off-peak months (p < .001). Children who underwent surgery during peak RSV season did not differ from the off-peak group in terms of age at operation, race, or comorbid conditions (i.e., congenital heart disease, newborn respiratory distress, and preoperative pneumonia). There was no association between hospital-specific RSV incidence at the time of surgery and postoperative mechanical ventilation, postoperative LOS, 30-day readmission rate or hospital billing charges.

DISCUSSION

Performing elective lung surgery in children with CLMs during peak viral season is not associated with adverse surgical outcomes or increased utilization of healthcare resources.

Diagnostic accuracy of imaging compared to histology in congenital lung malformations

INTRODUCTION

The aim of this study was to evaluate the accuracy of imaging tests (prenatal ultrasound [US] and postnatal computed tomography [CT]) in comparison to histology for diagnosis of congenital lung malformations (CLMs).

MATERIAL AND METHODS

Retrospective study of patients with a prenatal diagnosis of CLM whose postnatal follow-up included thoracic CT scan and histological examination of the lesion. We collected data on demographic variables, gestational age at diagnosis, US findings and the history of multiple gestation. We used the kappa coefficient to determine the level of agreement between the findings of prenatal US and postnatal tests (CT and histology).We analysed paired data on the size of the lesion, its location and the presence or absence of systemic arterial vascularization.

RESULTS

The sample included 56 patients with 57 lesions. The mean gestational age at diagnosis was 22.42 weeks (SD, 3.94) and 57% were male. Malformations most frequently involved the left lung and the lower lobes. The agreement between CT and histology in the detection of cystic lesions was moderate (κ = 0.55) but stronger compared to the agreement between US and histology (κ = 0.10). The agreement between CT and histology was substantial (κ = 0.66) in the detection of systemic vascularization of the lesion and stronger compared to the agreement between US and histology. Both imaging methods were highly accurate in the identification of the location of the pulmonary lesions.

CONCLUSIONS

postnatal CT offers a substantial concordance with histological findings, especially in the detection of systemic vascularization, and an accurate prediction of the anatomy of the lesion.

Congenital lung abnormalities on magnetic resonance imaging: the CLAM study

OBJECTIVES

Follow-up of congenital lung abnormalities (CLA) is currently done with chest computer tomography (CT). Major disadvantages of CT are exposure to ionizing radiation and need for contrast enhancement to visualise vascularisation. Chest magnetic resonance imaging (MRI) could be a safe alternative to image CLA without using contrast agents. The objective of this cohort study was to develop a non-contrast MRI protocol for the follow-up of paediatric CLA patients, and to compare findings on MRI to postnatal CT in school age CLA patients.

METHODS

Twenty-one CLA patients, 4 after surgical resection and 17 unoperated (mean age 12.8 (range 9.4-15.9) years), underwent spirometry and chest MRI. MRI was compared to postnatal CT on appearance and size of the lesion, and lesion associated abnormalities, such as hyperinflation and atelectasis.

RESULTS

By comparing school-age chest MRI to postnatal CT, radiological appearance and diagnostic interpretation of the type of lesion changed in 7 (41%) of the 17 unoperated patients. In unoperated patients, the relative size of the lesion in relation to the total lung volume remained stable (0.9% (range - 6.2 to + 6.7%), p = 0.3) and the relative size of lesion-associated parenchymal abnormalities decreased (- 2.2% (range - 0.8 to + 2.8%), p = 0.005).

CONCLUSION

Non-contrast-enhanced chest MRI was able to identify all CLA-related lung abnormalities. Changes in radiological appearance between MRI and CT were related to CLA changes, patients' growth, and differences between imaging modalities. Further validation is needed for MRI to be introduced as a safe imaging method for the follow-up of paediatric CLA patients.

KEY POINTS

• Non-contrast-enhanced chest MRI is able to identify anatomical lung changes related to congenital lung abnormalities, including vascularisation. • At long-term follow-up, the average size of congenital lung abnormalities in relation to normal lung volume remains stable. • At long-term follow-up, the average size of congenital lung abnormalities associated parenchymal abnormalities such as atelectasis in relation to normal lung volume decreases.

COllaborative Neonatal Network for the first European CPAM Trial (CONNECT): a study protocol for a randomised controlled trial

INTRODUCTION

Consensus is lacking on the optimal management of asymptomatic congenital pulmonary airway malformation (CPAM). For future studies, the CONNECT consortium (the COllaborative Neonatal Network for the first European CPAM Trial)-an international collaboration of specialised caregivers-has established consensus on a core outcome set of outcome parameters concerning respiratory insufficiency, surgical complications, mass effect and multifocal disease. These outcome parameters have been incorporated in the CONNECT trial, a randomised controlled trial which, in order to develop evidence-based practice, aims to compare conservative and surgical management of patients with an asymptomatic CPAM.

METHODS AND ANALYSIS

Children are eligible for inclusion after the CPAM diagnosis has been confirmed on postnatal chest CT scan and they remain asymptomatic. On inclusion, children are randomised to receive either conservative or surgical management. Subsequently, children in both groups are enrolled into a standardised, 5-year follow-up programme with three visits, including a repeat chest CT scan at 2.5 years and a standardised exercise tolerance test at 5 years.The primary outcome is exercise tolerance at age 5 years, measured according to the Bruce treadmill protocol. Secondary outcome measures are molecular genetic diagnostics, validated questionnaires-on parental anxiety, quality of life and healthcare consumption-, repeated imaging and pulmonary morbidity during follow-up, as well as surgical complications and histopathology. This trial aims to end the continuous debate surrounding the optimal management of asymptomatic CPAM.

ETHICS AND DISSEMINATION

This study is being conducted in accordance with the Declaration of Helsinki. The Medical Ethics Review Board of Erasmus University Medical Centre Rotterdam, The Netherlands, has approved this protocol (MEC-2022-0441). Results will be disseminated through peer-reviewed scientific journals and conference presentations.

TRIAL REGISTRATION NUMBER

NCT05701514.

Quantitative CT imaging analysis to predict pathology features in patients with a congenital pulmonary airway malformation

BACKGROUND

Risk for infection and potential malignant degeneration are the most common arguments for resecting asymptomatic Congenital Pulmonary Airway Malformations (CPAM). We aimed to investigate if CT- imaging characteristics can be used to predict histopathological features, by using an objective quantitative CT scoring method.

METHODS

Archival CPAM tissue samples were histologically re-assessed and patients who had a pre-operative volumetric CT-scan were included. Lung disease was quantified using the newly-developed congenital lung abnormality quantification(CLAQ) scoring method and obtained percentages were used to predict histopathological signs of inflammation and presence of mucinous proliferation (MP). Because MP is presumed a precursor for mucinous adenocarcinoma in situ (AIS) this method was also used to compare CT-scans of patients with AIS to those with only CPAM.

RESULTS

Thirty-three CPAM patients were included of which 13(39%) had histological signs of inflammation and 8(24%) had a MP. Patients with inflammation had a significantly smaller lesion (14% vs 38%) while those with MP had more extensive disease (54%vs17%). Patients with AIS had a significantly smaller lesion compared to CPAM patients (5%vs29%). Significant predictors for inflammation were smaller lesion size and percentage hypodensity within lesions while a larger lesion size and percentage parenchymal hyperdensity (solid lung tissue components) were predictors for MP as well as AIS.

CONCLUSIONS

Smaller CPAM lesions may be more susceptible to inflammation while larger lesions may be associated with the presence of MP. Parenchymal hyperdensity is found as a predictor for MP as well as AIS and should therefore elicit more extensive gross sampling.

LEVEL OF EVIDENCE

Level III.

The Management of Asymptomatic Congenital Pulmonary Airway Malformation: Results of a European Delphi Survey

Consensus on the optimal management of asymptomatic congenital pulmonary airway malformation (CPAM) is lacking, and comparison between studies remains difficult due to a large variety in outcome measures. We aimed to define a core outcome set (COS) for pediatric patients with an asymptomatic CPAM. An online, three-round Delphi survey was conducted in two stakeholder groups of specialized caregivers (surgeons and non-surgeons) in various European centers. Proposed outcome parameters were scored according to level of importance, and the final COS was established through consensus. A total of 55 participants (33 surgeons, 22 non-surgeons) from 28 centers in 13 European countries completed the three rounds and rated 43 outcome parameters. The final COS comprises seven outcome parameters: respiratory insufficiency, surgical complications, mass effect/mediastinal shift (at three time-points) and multifocal disease (at two time-points). The seven outcome parameters included in the final COS reflect the diversity in priorities among this large group of European participants. However, we recommend the incorporation of these outcome parameters in the design of future studies, as they describe measurable and validated outcomes as well as the accepted age at measurement.

Congenital lung abnormality quantification by computed tomography: The CLAQ method

INTRODUCTION

To date, no consensus has been reached on the optimal management of congenital lung abnormalities, and factors predicting postnatal outcome have not been identified. We developed an objective quantitative computed tomography (CT) scoring method, and assessed its value for clinical decision-making.

METHODS

Volumetric CT-scans of all patients born with a congenital lung abnormality between January 1999 and 2018 were assessed. Lung disease was quantified using the newly-developed congenital lung abnormality quantification (CLAQ) scoring method. In 20 equidistant axial slices, cells of a square grid were scored according to the abnormality within. The scored CT parameters were used to predict development of symptoms, and SD scores for spirometry and exercise tolerance (Bruce treadmill test) at 8 years of age.

RESULTS

CT-scans of 124 patients with a median age of 5 months were scored. Clinical diagnoses included congenital pulmonary airway malformation (49%), bronchopulmonary sequestration (27%), congenital lobar overinflation (22%), and bronchogenic cyst (1%). Forty-four patients (35%) developed symptoms requiring surgery of whom 28 (22%) patients became symptomatic before a CT-scan was scheduled. Lesional hyperdensity was found as an important predictor of symptom development and decreased exercise tolerance. Using receiver operating characteristic analysis, an optimal cut-off value for developing symptoms was found at 18% total disease.

CONCLUSION

CT-quantification of congenital lung abnormalities using the CLAQ method is an objective and reproducible system to describe congenital lung abnormalities on chest CT. The risk for developing symptoms may increase when more than a single lung lobe is affected.