The central tegmental tract refers mainly to the extrapyramidal tracts connecting between the red nucleus and the inferior olivary nucleus. This tract is one of the earliest regions in which myelination begins (9 months after conception) (3). The symmetrical CTT hyperintensities seen on T2-weighted images are an uncommon imagiologic finding (2).
The symmetrical central tegmental tract hyperintensity occurs more frequently during the early childhood between 1 and 5 years of age 2,3. It is encountered in a variety of settings including 2:
Occasionally it is found in children with no clinical neurological finding 2,3.
The aetiology of high T2W signal is unclear. Numerous theories for the pathogenesis have been suggested, for including intramyelination oedema, gliosis or secondary degeneration of the cerebral white matter 1.
Some authors, instead, have suggested that the majority of imaging findings simply represent a physiological maturation-related process 3.
- T2: symmetrical hyperintensities in the central tegmental tracts
- DWI/ADC: may show restricted diffusion
Treatment and prognosis
The meaning of this finding, its clinical correlation with various neurologic deficits and prognosis remains unclear, and in some instances it is reversible 3,4.
- 1. Shoko Yoshida, Katsumi Hayakawa, Akira Yamamoto, Noriko Aida, Souzo Okano, Hiroko Matsushita, Toyoko Kanda, Yuriko Yamori, Naoko Yoshida, Haruyo Hirota. Symmetrical central tegmental tract (CTT) hyperintense lesions on magnetic resonance imaging in children. (2009) European Radiology. 19 (2): 462. doi:10.1007/s00330-008-1167-7 - Pubmed
- 2. Paramdeep Singh, Amarpreet Kaur, Rupinderjeet Kaur, Simmi Aggarwal, Ramandeep Singh. Symmetrical central tegmental tract hyperintensities on magnetic resonance imaging. (2015) Journal of Pediatric Neurosciences. 10 (3): 235. doi:10.4103/1817-1745.165666 - Pubmed
- 3. Sergio Aguilera-Albesa, Andrea Poretti, Dagmar Honnef, Meral Aktas, Maria Eugenia Yoldi-Petri, Thierry A. G. M. Huisman, Martin Häusler. T2 hyperintense signal of the central tegmental tracts in children: disease or normal maturational process?. (2012) Neuroradiology. 54 (8): 863. doi:10.1007/s00234-012-1006-z - Pubmed
- 4. Takanashi J, Kanazawa M, Kohno Y. Central tegmental tract involvement in an infant with 6-pyruvoyltetrahydropterin synthetase deficiency. (2006) AJNR. American journal of neuroradiology. 27 (3): 584-5. Pubmed