Benign intracerebellar cyst without epithelial lining

Appearance of cerebellar cyst following microvascular decompression to treat hemifacial spasm: a report of two cases and literature review

Microvascular decompression (MVD) is an effective and safe approach for treating hemifacial spasm (HFS). Postoperative complications may include facial nerve palsy, hearing loss, intracerebral haematoma, and brainstem infarction. The occurrence of intracranial cyst following MVD is extremely rare, with few cases documented in the literature. Herein, the cases of two patients with HFS who developed ipsilateral cerebellar cyst following MVD are reported. The first patient was a 50-year-old male presenting with a 6-year history of HFS on the right side of his face. MVD was performed, and 12 days postoperatively he developed dizziness and nausea. Magnetic resonance imaging (MRI) showed a cyst in the ipsilateral cerebellum. Antibiotic treatment provided no benefit, and the cyst was drained. The second patient was a 44-year-old female presenting with a 4-year history of HFS on the right side of her face. MVD was performed, and 18 days following surgery, she developed dizziness and nausea. MRI showed an ipsilateral cerebellar cyst. Conservative treatment was applied and the cyst shrunk. At the 2-month follow-up appointment, symptoms were completely resolved in both patients. Cerebellar cyst is a rare complication following MVD. Timely diagnosis and appropriate treatment should be emphasized, and surgical treatment may be unnecessary.

Iatrogenic postoperative cerebellar cyst

Cerebellar cyst is a known but uncommon entity. It is congenital in most cases, or may develop after brain parenchyma injuries or interventions. To our knowledge, de novo cerebellar cyst after extra-axial tumor excision, has not been described in the literature. We present the first reported case of a de novo cerebellar cyst developing in a 70-year-old woman following retrosigmoid craniotomy for vestibular schwannoma excision, and discuss the possible causes. Following cyst fenestration, there was no clinical or radiological evidence of a residual cyst.

Rare occurrence of intracerebellar colloid cyst. Case report

Colloid cysts are rare intracerebral lesions that are preferentially encountered within the third ventricle. There are only a few reports in which colloid cysts are described in other locations such as the fourth ventricle. A symptomatic intracerebellar colloid cyst in a 45-year-old woman is described. The patient presented with headache, gait disturbance, and nausea. Neuroradiological imaging revealed compression of the fourth ventricle, hydrocephalus, and an intracerebellar cystic lesion measuring 4 x 5 cm that had a small peripheral solid portion. The cyst was successfully removed via a paramedian suboccipital approach. Postoperatively, the patient recovered quickly. The findings in the present report represent an additional example of the broad spectrum of cystic lesions encountered in the cerebellum.