Background: Peripheral nerve sheath tumors are benign or malignant. Schwannoma is a benign peripheral nerve sheath tumor originating from the Schwann cells that slowly grows eccentric to the nerve axis. Malignant transformation of a schwannoma is rare. Case presentation: A 73 years old women that presented in our medical service for other medical problems was diagnosed with a tumor of the lower...

Objective To present a case of successful repair of a spontaneous cerebrospinal fluid leak in a previously unreported anatomic site. Methods Retrospective chart review. Results A 48-year-old woman developed a spontaneous cerebrospinal fluid leak from the optic nerve sheath and underwent a multilayer endoscopic closure with no damage to the optic nerve. Conclusion Endoscopic surgeons can s...

The optic nerves are well demonstrated by high-resolution computed tomography. Involvement of the optic nerve by optic gliomas and optic nerve sheath meningiomas is well known. However, nonneoplastic processes such as increased intracranial pressure, optic neuritis, Grave ophthalmopathy, and orbital pseudotumor may also alter the appearance of the optic nerve/sheath on computed tomography. Cert...

Fractionated stereotactic radiation has become the standard treatment of meningioma of the optic nerve sheath. The mechanism responsible for improvement in visual function is unclear, because neuroimaging after treatment usually shows no discernable change in tumor appearance. We report immediate regression of optociliary shunt vessels in a patient after radiation treatment of an optic nerve sh...

Malignant peripheral nerve sheath tumor (MPNST) is a rare soft tissue sarcoma arising from neuroectoderm-derived cells comprising the outer coverings of peripheral nerves. Given the diverse cell types comprising the peripheral nerve sheath, both benign and malignant nerve sheath tumors display a wide range of histologic appearances. MPNST can arise either in association with proximal nerve trun...

Purpose To use finite element (FE) analysis to predict the optic nerve sheath traction forces that act on the optic nerve head (ONH) following horizontal eye movements, and the resulting stress levels in the peripapillary connective tissues of the ONH (Bruch's membrane [BM] and sclera). Methods An FE model of a healthy eye was reconstructed in primary gaze position that included details from ...

PNI describes a microscopic finding of tumor infiltration along a nerve, and is distinguished from Perineural Spread (PNS), which describes the presence of gross tumor growth along a nerve distinct from the main tumor mass on imaging. PNI is defined as cancer cell invasion in, around, and through nerves where tumor cells are seen within any of the layers (epineurium, perineurium, endoneurium) o...

First proposed by De Wecker! in 1872 as a treatment for neuroretinitis, optic nerve sheath decompression (or fenestration) is an operation that has caused much controversy. This surgical therapy was not seriously considered until Davidson" and Smith, Hoyt, and Newton" reintroduced it in 1969 as an alternative therapy for chronic disk edema. Over the next 19 years, however, only about 60 cases o...

STUDY OBJECTIVE We investigate the test performance of emergency physician-performed sonographic measurement of optic nerve sheath diameter for diagnosis of increased intracranial pressure. METHODS Children between the ages of 0 and 18 years with suspected increased intracranial pressure were prospectively recruited from the emergency department and ICU of an urban, tertiary-level, freestandi...

BACKGROUND Optic nerve sheath meningiomas account for only 2% of orbital lesions and 42% of optic nerve tumors. Diagnosis remains difficult because histologic confirmation carries a high risk of visual loss. Therefore, a less invasive and specific diagnostic method for differentiating optic nerve sheath meningiomas from other optic nerve lesions is needed to overcome the limitations of computed...