Pseudotumour cerebri due to a torcular epidermoid cyst

Acute-onset diplopia from intracranial hypertension due to torcular herophili obstruction by an hemorrhagic intradiploic epidermoid cyst

BACKGROUND

Epidermoid cysts are benign slow-growing congenital lesions, constituting approximately 1% of all cranial tumors. Most of these lesions are located intradurally, while about 10-25% of them are located within the diploic spaces. Intradiploic epidermoid cysts are usually discovered incidentally and may remain asymptomatic for many years, but in rare instances, they may grow intracranially and produce brain compression. Sometimes, intradiploic epidermoid cysts may occlude the main cranial venous sinuses causing intracranial hypertension.

CASE DESCRIPTION

We present the case of a 24-year-old male harboring a paramedian right occipital intradiploic cyst with erosion of both outer and inner bony tables, which occluded the torcular herophili producing a worsening symptomatology with acute-onset diplopia from right sixth cranial nerve palsy; the patient also presented bilateral papilledema, but only reported mild headache and dizziness. Neuroradiological studies evidentiated a lesion compatible with intradiploic epidermoid cyst with intralesional hemorrhagic component, overlying and almost completely occluding the torcular herophili. Considering the fast worsening of symptomatology and the evidence of intracranial hypertension, the patient was operated on immediately after completion of clinical and radiological assessment. The lesion was radically removed with almost immediate reversal of signs and symptoms. Histopathology confirmed the diagnosis of epidermoid cyst with intralesional hemorrhagic components.

CONCLUSION

Intradiploic epidermoid cysts may cause intracranial hypertension by occlusion of main cranial venous sinuses; intralesional hemorrhage may act as precipitating factor in occlusion of the torcular herophili, producing rapidly worsening intracranial hypertension, which requires prompt surgical treatment to reverse symptomatology. Radical surgical resection is necessary to avoid recurrence.

Epidermoid Cyst with Torcular Herophili Obstruction and Unusual Venous Drainage

BACKGROUND

An epidermoid cyst arising from diploic space in the skull can cause an intracranial mass effect with compression of the underlying venous sinuses.

CASE DESCRIPTION

A 66-year-old woman came to us with a persistent headache and unsteadiness. Computed tomography demonstrated an occipital bone cystic lesion with an intracranial mass effect overlying the torcular herophili, with high-intensity findings in diffusion-weighted magnetic resonance imaging. Cerebral angiogram demonstrated obstruction of the torcular herophili with development of diploic venous drainage. The patient underwent removal of the lesion and a cranioplasty procedure. The diagnosis was torcular epidermoid cyst. The postoperative course was uneventful, and the symptoms were resolved.

CONCLUSIONS

Development of diploic venous drainage contributed to avoidance of critical intracranial hypertension during slow growth of a torcular epidermoid cyst.

Atraumatic epidural hematoma secondary to a venous sinus thrombosis: a novel finding

Venous sinus thrombosis is a rare entity that usually arises secondary to underlying thrombophilia, neoplasm, head injury, or infection. Tympanic infection accounts for the majority of infectious etiologies, and the sigmoid sinus becomes the likely anatomical site of thrombosis. The authors report a case involving a child with recurrent otitis media who presented with an atraumatic epidural hematoma secondary to sigmoid sinus thrombosis. Intraoperative evaluation revealed epidural hemorrhage that originated from the venous sinus, with hemorrhagic products of varying ages. To the authors' knowledge, this is the first reported case of a venous sinus thrombosis resulting in an epidural hematoma.

Extradural hematoma causing venous sinus obstruction and pseudotumor cerebri syndrome

CASE REPORT

The case of a small right occipital extradural hematoma in a 10-year-old girl is presented. The patient had bifrontal occipital headache out of proportion to the size of the hematoma, as well as diplopia. MR venography revealed compression and occlusion of the dominant right transverse sinus resulting in a pseudotumor cerebri syndrome.

DISCUSSION

The relationship between venous sinus obstruction and the pseudotumor syndrome is discussed. Clinicians should be aware of the possible effects of an extra-axial collection on the cerebral venous sinuses.

Cranial venous outflow obstruction and pseudotumor Cerebri syndrome

The pathophysiology of PTS including idiopathic intracranial hypertension or 'BIH', remains controversial. The older literature frequently referred to pathology in the cerebral venous drainage but more modern imaging techniques (CT and early MR) failed to reveal gross venous pathology. The role of impaired cranial venous outflow has recently been re-examined in the light of new methods of investigation (advanced MR venography and direct microcatheter venography with manometry) and of treatment (venous sinus stenting). Venous sinus obstruction in PTS is a more common factor in the pathogenesis of the condition than previously recognised. Venous obstruction may be primary, that is, it is the underlying aetiological factor in PTS. Venous sinus obstruction may also be secondary to raised CSF pressure which may exacerbate problems with intracranial compliance and raised CSF pressure. Early experience with venous stenting suggests that it may be a helpful treatment for patients with PTS but more experience and longer follow-up is required to define the subgroups of patients for whom it is most appropriate.