Asymptomatic traumatic rupture of an intracranial dermoid cyst: A case report

Abstract

Background: Previous studies reported that most of the intracranial dermoid cyst ruptures were spontaneous, and only a few were traumatic, with asymptomatic much rarer than the symptomatic ruptures. Hence, how to deal with the asymptomatic traumatic rupture of intracranial dermoid cyst remains a challenge in the clinic.

Case summary: A 59-year-old man was accidentally diagnosed with intracranial dermoid cyst through a cranial computed tomography (CT) scan due to a car accident. A mixed-density lesion with fat and a calcified margin was observed in the midline of the posterior fossa, accompanied with lipid droplet drifts in brain sulci, fissures, cisterns, and ventricles. After 1 wk of conservative observation, no change was observed on the updated cranial CT scan. After 2 wk of conservative observation, magnetic resonance imaging examination confirmed that the lesion was a traumatic rupture of a posterior fossa dermoid cyst with lipid droplet drifts. As the patient exhibited no adverse symptoms throughout the 2 wk, a 6-mo follow-up visit was arranged for him instead of aggressive treatment. Nonetheless, the patient did not show any abnormal neurological symptoms in the 6 mo of follow-up visits.

Conclusion: Asymptomatic traumatic rupture of intracranial dermoid cyst could be just followed or treated conservatively rather than treated aggressively.

Keywords: Case report; Computed tomography; Intracranial dermoid cyst; Magnetic resonance imaging; Rupture; Traumatic.

Figure 1

Cranial computed tomography scan showed a mixed-density lesion in the midline of the posterior fossa (arrow), with a fat-density area inside and calcified margin (arrow), as well as lipid droplet drifts in sulci, cisterns, and lateral ventricles (arrows).

Figure 2

Cranial magnetic resonance imaging at 2 wk after injury. A: The lesion presented hyperintensity on axial T2-weighted imaging (arrow); B: The lesion presented hyperintensity on diffusion weighted imaging (arrow); C: The lesion presented hypointensity on T1-fluid attenuated inversion recovery (FLAIR) (arrow); D: The lesion presented hypointensity on T2-FLAIR (arrow); E: No enhancement in the cystic lesion area was observed on axial T1-FLAIR (arrow); F: On the enhanced sagittal T1-FLAIR, no enhancement was observed in the cystic lesion, while the fat area presented hyperintensity and extended to the subarachnoid space (arrow).