Rapidly progressive medulloblastoma initially mimicking idiopathic intracranial hypertension and Chiari I malformation: A case report

Abstract

Introduction Medulloblastoma (MDB) often causes signs and symptoms of elevated intracranial pressure (ICP) with imaging findings of mass lesion. Here, we report a case of MDB who initially presented with clinical features imitating idiopathic intracranial hypertension (IIH) and Chiari I malformation (CIM). Case presentation A 19-year-old man had clinical symptoms of elevated ICP without mass lesion on imaging. He was initially diagnosed with IIH and CIM, which underwent shunt surgery and posterior fossa decompression. Later on, he had recurrent symptoms, and the new imaging revealed the development of MDB in the right cerebellar hemisphere. After tumor resection, the patient rapidly deteriorated with spinal metastases. Discussion and conclusion Management of the coexistence between IIH and CIM in patients with rising ICP is complicated. MDB is one of the aggressive malignant brain tumors showing a wide range of imaging features, including non-enhancing mass. Therefore, recognizing the possibility of brain tumors mimicking IIH or CIM is crucial.

Primary Leptomeningeal Medulloblastoma in Adults: A Diagnostic Challenge—Case Report and Systematic Review

“… 11 19 While some authors have demonstrated the presence of contrast-enhancing leptomeninges on CT 4 7 and MRI, 6 8 9 10 12 in our case, no variation was recognized after contrast administration both before and after the endoscopic procedure. Our neuroradiological investigations demonstrated only a Chiari-like malformation 11 16 with triventricular hydrocephalus 6 11 16 and nonspecific cerebellar swelling with some hyperintensities in FLAIR and T2-weighted sequences. 9 11 …”

“… 5 In most cases, it appears to be secondary to the primary mass. 7 16 Although subarachnoid seeding is common, occurring in approximately 33% of MB at the time of diagnosis, 5 purely diffuse leptomeningeal tumor spread without mass lesion in an adult patient is rare, 4 5 6 7 8 9 10 11 12 17 and has, to the best of our knowledge, been only reported few times in the literature, 4 5 6 7 8 9 10 11 12 and all the described patients had very unfavorable prognosis. 4 5 6 7 8 9 10 11 12 …”

“…5 In most cases, it appears to be secondary to the primary mass. 7,16 Although subarachnoid seeding is common, occurring in approximately 33% of MB at the time of diagnosis, 5 purely diffuse leptomeningeal tumor spread without mass lesion in an adult patient is rare, [4][5][6][7][8][9][10][11][12]17 and has, to the best of our knowledge, been only reported few times in the literature, 4-12 and all the described patients had very unfavorable prognosis. [4][5][6][7][8][9][10][11][12] Generally, PL-MB manifests with headache 4,6,8,10,12,18 and visual abnormalities 4,6,8,10,18 lasting a few months, and may also result in rapid neurologic deterioration.…”

“…Thus, we initially treated her for chronic triventricular hydrocephalus, similar to the authors who used a ventriculoperitoneal shunt. 8 16 In contrast, in subjects with rapid neurological deterioration, Rushing et al 11 preferred an external ventricular drainage for an acute-onset hydrocephalus, while Ferrara et al 7 and Guo et al 8 opted for an emergent posterior fossa decompression.…”

“…Contemporary evaluation procedures in MB include MRI of the brain and spinal cord, histological examination of biopsy or resected tumor specimens, and analysis of CSF cytology. 14 On MRI, MB appears as a heterogeneous enhancing well-defined mass lesion, 5 13 16 often with surrounding cystic degeneration of necrosis. 5 It is generally iso- or hyperintense on FLAIR and T2-weighted sequences, and commonly appears heterogeneous because of cyst formation, calcification, and necrosis.…”