Lymphatic plastic bronchitis: a study based on CT and MR lymphangiography

Abstract

Objectives: To investigate the diagnostic value of CT lymphangiography (CTL) and non-contrast MR lymphangiography (MRL) in lymphatic plastic bronchitis.

Materials and methods: The clinical and imaging data of 31 patients with lymphatic plastic bronchitis diagnosed by clinical, imaging and pathological results were retrospectively analyzed. All patients underwent CTL and MRL. The imaging findings of patients include: (i) abnormal lymphatic reflux of the bronchial mediastinal trunk, the subclavian trunk, the cervical trunk, the thoracic duct and the right lymphatic duct; Abnormal CTL reflux refers to abnormal iodide deposition outside the normal lymphatic reflux pathway; If the MRL can observe abnormal lymphatic dilatation, hyperplasia, or morphological abnormalities, it is assumed that abnormal lymphatic reflux may be present.; (ii) abnormal morphological changes of lymphatic vessels at the extremity of the thoracic duct, the extremity of the right lymphatic duct and the mediastinum, such as spot-like or tubular, cystic changes; (iii) abnormal CTL and MRL signs in the lungs. The Mcnemar test was used to compare the parameters between CTL and MRL. P< 0.05 was statistically significant. The Kappa test was used to evaluate the consistency of CTL and MRL in evaluating lymphatic plastic bronchitis.

Results: MRL was superior to CTL in detecting abnormal lymphatic reflux in the right lymphatic vessel, thoracic duct, cervical trunk and subclavian trunk (P< 0.05).and the diagnostic consistency was general (Kappa < 0.40). There was no significant difference between MRL and CTL in the detection of abnormal lymphatic reflux in the bronchial mediastinal trunk (P> 0.05), and the diagnostic consistency was good (Kappa > 0.60). MRL was superior to CTL in detecting lymphatic abnormalities such as cystic changes at the extremity of the thoracic duct, spot-like or tubular changes at the extremity of the right lymphatic duct, cystic changes at the extremity of the right lymphatic duct, and cystic changes in the mediastinum (P< 0.05), and the diagnostic consistency was poor, fair, fair, and moderate (Kappa < 0.60), respectively. MRL and CTL showed abnormal signs in the lung: CTL was superior to MRL in showing the thickening of interlobular septum, lung nodules and airway stenosis (P< 0.05), and the diagnostic consistency was moderate, moderate and poor (Kappa < 0.60). There was no significant difference between CTL and MRL in atelectasis, consolidation in lobar and segmental distribution, consolidation in non-lobar and segmental distribution, and the thickening of the bronchovascular bundle (P> 0.05), and the diagnostic consistency was very good, very good, good, good (Kappa > 0.60). There was no significant difference between CTL and MRL in ground glass opacity, airway wall thickening and intralobular interstitial thickening (P> 0.05), and the diagnostic consistency was average, fair and poor (Kappa < 0.40).

Conclusion: The MRL is superior to CTL in showing the abnormalities of the thoracic duct, the right lymphatic duct and other abnormal lymphatic vessels. CTL is superior to MRL in the detection of pulmonary abnormalities. The combination of CTL and MRL can provide more comprehensive imaging information for diagnosing and treating lymphatic plastic bronchitis.

Keywords: Lymphangiography; Lymphatic; Magnetic resonance imaging; Plastic bronchitis; Tomography, X-ray.

Fig. 1

Flow diagram of study cohort

Fig. 2

A The coronal MRL shows cystic and tortuous lymphatic vessels in the extremity of thoracic duct (white short arrow) and bilateral hilum (white long arrow). B The coronal CTL shows abnormal contrast medium accumulation in the bilateral hilum (white long dashed arrow) and subclavian region (white arrowhead)

Fig. 3

A The coronal MRL shows multiple cystic hyperintense in the upper mediastinum (black arrowhead), left neck (white short arrow), right neck (black short arrow), and spleen (white arrowhead). Multiple tubular hyperintense were found in bilateral chest walls (white asterisks) and bilateral hilum (white long arrows). B The coronal CTL shows abnormal contrast medium accumulation in the bilateral hilum (black asterisk), and cystic hypodensity in the spleen (black long arrow)

Fig. 4

A MRL shows hyperintense in the right lower lung (white short arrow). B CTL shows increased transmittance of the lungs and diffuse distribution of GGO (black short arrow)

Fig. 5

The axial chest CT of lung window shows diffuse nodules in the lungs, with blurred edges and centered on acini (black short arrow)

Fig. 6

The chest CT of the lung window shows thickening of the right bronchovascular bundle (black long arrow) and ground glass opacity in the posterior segment of the right upper lobe (asterisk)

Fig. 7

The chest CT of the lung window shows multiple punctate nodules near the oblique fissure of the posterior segment of the right upper lobe, which was called "frog-spawn sign" (white short arrow)