Objective: Underconnectivity in the resting brain is not consistent in autism spectrum disorder (ASD). However, it is known that the functional connectivity of the default mode network is mainly decreased in childhood ASD. This study investigated the brain network topology as the changes in the connection strength and network efficiency in childhood ASD, including the early developmental stages. Methods: In this study, 31 ASD children aged 2–11 years were compared with 31 age and sex-matched children showing typical development. We explored the functional connectivity based on graph filtration by assessing the single linkage distance and global and nodal efficiencies using resting-state functional magnetic resonance imaging. The relationship between functional connectivity and clinical scores was also analyzed. Results: Underconnectivities within the posterior default mode network subregions and between the inferior parietal lobule and inferior frontal/superior temporal regions were observed in the ASD group. These areas significantly correlated with the clinical phenotypes. The global, local, and nodal network efficiencies were lower in children with ASD than in those with typical development. In the preschool-age children (2–6 years) with ASD, the anterior-posterior connectivity of the default mode network and cerebellar connectivity were reduced. Conclusion The observed topological reorganization, underconnectivity, and disrupted efficiency in the default mode network subregions and social function-related regions could be significant biomarkers of childhood ASD.

Adenoid cystic carcinoma formerly called cylindroma is rare tracheal tumor. Characteristics of adenoid cystic carcinoma are infiltrative nature with local recurrence tendency and long natural course of the disease. Adenoid cystic carcinomas develop most commonly in the trachea. Primary resection and end-to-end anastomosis of the involved airway are treatment of choice. And postoperative radiation therapy might be useful, particularly when the surgical margins are not ample. We report two cases of adenoid cystic carcinoma of trachea diagnosed by flow-volume curve.
Adenoids* ; Carcinoma, Adenoid Cystic* ; Recurrence ; Trachea*