Congenital lung abnormality quantification by computed tomography: The CLAQ method

Abstract

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 cutoff 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.

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

“…The relation between mediastinal shift and long-term outcome is yet to be investigated. Somewhat surprisingly, the COS produced in this study does not include outcome parameters directly linked to lesion size, even though several studies found a correlation between lesion size and symptom development [ 40 , 41 ]. However, lesion size can be linked to mediastinal shift to a certain degree, as a large lesion will have a higher chance of causing this shift.…”

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

“…CPAM development/postsurgical appearance on chest CT imaging—scored according to the congenital lung abnormality quantification (CLAQ) method. 51 …”

“…The radiological appearance of the CPAM on CT imaging will be scored according to the previously published CLAQ-method, and compared between the treatment groups using the Mann-Whitney U test. 51 …”

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

“…Hybrid samples meeting aforementioned histological criteria as well as systemic arterial blood supply, were also included. Patients were excluded if CT-scans did not allow reliable scoring, such as CT-scans with a slice thickness exceeding 3 mm, or with poor image quality, or a large pneumothorax [36] .…”

“…Clinical data were obtained from the electronic patient records and included neonatal data and information on the surgical procedure. In our center, we adhere to a wait-and-see policy for all CLA patients unless they exhibit symptoms, such as respiratory distress, recurrent infections or cardiac volume overload [36] . Lung disease on chest CT was quantified using the newly-developed congenital lung abnormality quantification (CLAQ) scoring method [36] .…”