The value of MRI in the diagnosis of pediatric head and neck lymphatic malformations: A study of 46 surgical cases

Objective To discuss the value of MRI in diagnosing and evaluating the pediatric head and neck lymphatic malformations (HNLMs). Methods We performed a retrospective review of 46 children who were referred to our hospital in the last decade for the treatment of HNLMs. Results About 34 cases confirmed with intralesional hemorrhage while the capsule contents were dark red or light bloody liquid. The remaining 12 pure HNLMs were filled with yellow clear or watery liquid. The multilocular HNLMs accounted for 95.7 % (44/46). The accuracy of contrast enhanced MRI (CE-MRI) diagnosis of HNLMs was 100 %. On MRI, the HNLMs appeared as irregular shape [95.7 % (44/46)], clear boundary [91.3 % (42/46)], infiltrative growth [91.3 % (42/46)] cystic masses. The cystic wall and septa were hyperintense on T1WI and hypointense on T2WI (100 %), and displayed enhancement. The capsule contents had hypointense on T1WI and hyperintense on T2WI in 18 cases (pure HNLMs,12; intracystic hemorrhage,6), while that of mixed signal in 28 cases (pure HNLMs,0; intracystic hem-orrhage,28). Capsule contents were enhanced in 22 cases (pure HNLMs,1; intracystic hemorrhage,21), while the remaining 24 without enhancement (pure HNLMs,11; intracystic hemorrhage,13). Liquid-liquid levers were found in 21 cases (pure HNLMs,0; intracystic hemorrhage,21). There were statistical differences in capsule contents signal, enhancement, and liquid-liquid levels between the two groups (P < 0.05). Conclusions On MRI, HNLMs typically show a thin-walled, well-circumscribed, irregularly shaped, infiltrative, unenhanced, multi-locular cystic mass with hypointense on T1WI and hyperintense on T2WI. The capsule wall and septa are hyperintense on T1WI, hypointense on T2WI, and display enhancement. Changes in the signal of capsule con-tents or appearance of liquid-liquid levels indicate intracystic hemorrhage.