case_images: PMC11311167_01
case_images: Preoperative computed tomography image shows a round, cranial hypodense dermoid cyst on the midline of the posterior fossa.
case_images: 10.1177_2050313X241266427-fig1.jpg
case_images: PMC11311167_01_10.1177_2050313X241266427-fig1.jpg
case_images: fig1-2050313X241266427
case_images: The CT scan revealed a well-defined, rounded, cranial hypodense lesion on the midline of the posterior fossa (Figure 1).
case_images: (a) and (b) Sagittal and axial cranial magnetic resonance imaging shows a median, rounded, cystic, subtentorial mass in the posterior fossa with ring enhancement of the cystic walls AND a linear dermal sinus connecting with the dura.
case_images: 10.1177_2050313X241266427-fig2.jpg
case_images: PMC11311167_01_10.1177_2050313X241266427-fig2.jpg
case_images: fig2-2050313X241266427
case_images: These clinical findings, correlated with the prior MRI results (Figure 2), which demonstrated a cyst communicating from the meninges to the skin surface, led to the suspicion of an infection in the cyst.
case_images: Intraoperative photograph indicates, the sinus tract (thick arrow), and the dermoid cyst (thin arrow).
case_images: 10.1177_2050313X241266427-fig3.jpg
case_images: PMC11311167_01_10.1177_2050313X241266427-fig3.jpg
case_images: fig3-2050313X241266427
case_images: Subsequently, the patient underwent a sub-occipital craniotomy, during which a midline dermal cyst connected to a complete cerebellar fistula was identified and completely resected (Figure 3).