J Yeungnam Med Sci.  2022 Oct;39(4):332-335. 10.12701/yujm.2021.01172.

Recovery of the ascending reticular activating system and consciousness following comprehensive management in a patient with traumatic brain injury: a case report

• Jang SH
• Kwon YH

• KMID: 2534661
• DOI: http://doi.org/10.12701/yujm.2021.01172

Abstract

We report on changes in the ascending reticular activating system (ARAS) concurrent with the recovery of impaired consciousness following rehabilitation and cranioplasty in a patient with traumatic brain injury (TBI), which were demonstrated on diffusion tensor tractography (DTT). A 34-year-old male patient was diagnosed with a traumatic intracerebral hemorrhage after falling from a height of approximately 7 m and underwent a right frontoparietotemporal decompressive craniectomy and hematoma removal. At 5 months after onset, when starting rehabilitation, the patient showed impaired consciousness, with a Glasgow Coma Scale (GCS) score of 4. Comprehensive rehabilitative therapy was provided until 14 months after onset, and his GCS score improved to 8. Cranioplasty was performed using auto-bone at 14 months after onset. One month after cranioplasty, his GCS score improved to 12. On the 15-month DTT, the deviated lower dorsal ARAS was restored on both sides, and the right side had become thicker. The right lower ventral ARAS was reconstructed, and increased neural connectivity of the upper ARAS was detected in both the prefrontal cortices. Thus, changes in the ARAS were demonstrated in a patient with TBI during recovery of consciousness following rehabilitation and cranioplasty.

Keyword

Ascending reticular activating system; Consciousness; Diffusion tensor tractography; Minimally conscious state; Vegetative state

Figure

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  Fig. 1. (A) Brain magnetic resonance images taken at 5 months and 15 months after onset show leukomalactic lesions in the right parietal and occipital lobes, both frontal and temporal lobes, and left basal ganglia. (B–D) Results of diffusion tensor tractography (DTT) for the ascending reticular activating system (ARAS) of the patient. On 5-month DTT, in the lower dorsal ARAS, the upper portions are deviated to the left side and thin on the right side (black arrow). The lower ventral ARAS is not reconstructed on both sides, and decreased neural connectivity of the upper ARAS is detected in both prefrontal cortices and both basal forebrains. By contrast, on 15-month DTT, the deviated lower dorsal ARAS is restored on both sides and the thinned right side has become thicker (black arrow). The right lower ventral ARAS (yellow arrow) is reconstructed and increased neural connectivity of the upper ARAS is detected in both prefrontal cortices (pink arrows) and anterior cingulums (green arrows).

Reference

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