Traumatic trigeminal neuropathy after whiplash injury: A case report

RATIONALE: Many studies using diffusion tensor tractography (DTT) have reported trigeminal neuropathy in various neurological diseases. However, no study on traumatic trigeminal neuropathy following whiplash has been reported. PATIENT CONCERNS: A 51-year old female suffered an indirect head trauma resulting from a flexion-hyperextension injury. At approximately 30 minutes after onset, she began to sense a headache in the left frontal area and sensory changes in the left facial area, signs that intensified with the passage of time. At 7 days after onset, she visited the rehabilitation department of our university hospital and described the characteristics and severity of pain as follows: headache on the left frontal area including the forehead with intermittent squeezing and numbness sensations. Her visual analog scale pain score was 6 with her left cheek having a continuous, dull, swelling sensation (visual analog scale score: 1). On neurological examination, she revealed mild allodynia without hyperalgesia or somatosensory change on the head, cheek, tongue, and oral cavity. DIAGNOSIS: Diffusion tensor imaging data were acquired 7 days after onset. On DTT, the left trigeminal nerve showed discontinuation in the middle portion compared to that of the right trigeminal nerve. Traumatic trigeminal neuropathy was diagnosed based on her clinical features and DTT findings. INTERVENTION: She was prescribed carbamazepine (200 mg/day) and pregabalin (150 mg/day), and her facial pain was well-controlled to a tolerable level. OUTCOMES: These drugs were stopped after approximately 7 month's administration, however, she did not complain of facial pain. LESSONS: By using DTT, we demonstrated traumatic trigeminal neuropathy in a patient with whiplash. We suggest that DTT would be a useful tool for detection of traumatic trigeminal neuropathy in patients who show clinical features of trigeminal neuropathy following whiplash.