Progress in the application of optic nerve sheath fenestration in the treatment of intracranial hypertensive optic neuropathy / 国际眼科杂志(Guoji Yanke Zazhi)

@#Optic nerve sheath fenestration(ONSF), also known as optic nerve sheath decompression, was first proposed by Wecker. The procedure involves cutting incisions or windows in the retrabulbar optic nerve sheath to release the cerebral spinal fluid from the subarachnoid space of the optic nerve, reducing the pressure surrounding the optic nerve. With the development of surgical instruments and procedures, the safety of ONSF has been significantly improved with infrequent complications. Through the past three decades, more and more ophthalmologists realized that ONSF is an effective surgical treatment to stabilize or improve visual loss in idiopathic intracranial hypertension(IIH). Additionally, much progress in the use of ONSF has been made on secondary intracranial hypertension due to cerebral venous sinus occlusion, <i>Cryptococcal</i> meningitis, and intracranial mass or tumors. In this paper we review the application of ONSF in IIH, and secondary intracranial hypertension. From the review, it indicates ONSF is a good surgical alternative for ophthalmologists. It also indicates that ONSF can be used to prevent or halt progressive visual loss associated with intracranial hypertension, particularly when other treatment modalities fail to protect vision.

Controversies: Optic nerve sheath fenestration versus shunt placement for the treatment of idiopathic intracranial hypertension.

Background: Idiopathic intracranial hypertension (IIH) has been increasing in prevalence in the past decade, following the obesity epidemic. When medical treatment fails, surgical treatment options must be considered. However, controversy remains as to which surgical procedure is the preferred surgical option – optic nerve sheath fenestration (ONSF) or cerebrospinal fluid (CSF) shunting – for the long‑term treatment of this syndrome. Purpose: To provide a clinical update of the pros and cons of ONSF versus shunt placement for the treatment of IIH. Design: This was a retrospective review of the current literature in the English language indexed in PubMed. Methods: The authors conducted a PubMed search using the following terms: Idiopathic IIH, pseudotumor cerebri, ONSF, CSF shunts, vetriculo‑peritoneal shunting, and lumbo‑peritoneal shunting. The authors included pertinent and significant original articles, review articles, and case reports, which revealed the new aspects and updates in these topics. Results: The treatment of IIH remains controversial and lacks randomized controlled clinical trial data. Treatment of IIH rests with the determination of the severity of IIH‑related visual loss and headache. Conclusion: The decision for ONSF versus shunting is somewhat institution and surgeon dependent. ONSF is preferred for patients with visual symptoms whereas shunting is reserved for patients with headache. There are positive and negative aspects of both procedures, and a prospective, randomized, controlled trial is needed (currently underway). This article will hopefully be helpful in allowing the reader to make a more informed decision until that time.

Vertical lid split approach for optic nerve sheath decompression.

We describe a vertical lid split orbitotomy approach to perform optic nerve sheath fenestration which was done in a patient with idiopathic intracranial hypertension. A vertical lid split incision was used to enter the superomedial orbit and approach the optic nerve sheath. This approach resulted in a successful nerve sheath fenestration, with improvement in the patient's symptoms. The vertical lid split incision provides access to the optic nerve sheath with minimal morbidity and may be an option for optic nerve sheath decompression.

"La obstrucción estaba abajo": tumores de la médula espinal e hipertensión intracraneal

Aumento de la presión intracraneal, hidrocéfalo y papiledema son observados ocasionalmente en pacientes portadores de tumores medulares en la región cervical o en la unión craneocervical, y entre otros, la obstrucción mecánica de la circulación del líquido cefalorraquídeo es asumida como responsable para tales síntomas y signos. No obstante, la hipertensión intracraneal es un raro fenómeno en tumores espinales de localización tóracolumbar. Los autores describen dos pacientes en quienes un tumor en tal localización (schwannoma benigno y paraganglioma) se asoció a síntomas de hipertensión intracraneal, hidrocefalia y papiledema. Se piensa que este tipo de lesiones puede interferir activamente en la dinámica del flujo del líquido cefalorraquídeo en razón de que la ocupación de espacio impide la expansión del saco dural y espacio subaracnoideo espinal que se piensa juegan algún papel en la compensación de los cambios de volumen y la presión intracraneal

Increased intracranial pressure, hydrocephalus and papilledema are occasionally observed in patients harboring spinal tumors in the cervical region or at the craniocervical junction, and among others, the mechanical obstruction to the cerebrospinal fluid circulation is assumed to be responsible for such symptoms and signs. However, increased intracranial pressure is very rare in spinal tumors located in the thoraco-lumbar region. Two patients are described by the authors in whom a benign thoracolumbar tumor (benign schwannoma and paraganglioma) was associated with symptoms of increased intracranial pressure, hydrocephalus and papiledema. It has been suggested that this kind of lesions could actively interfere with cerebrospinal fluid dynamics by their mass effect, especially by preventing the expansion of the dural sac and spinal subarachnoid space which may play some roce in compensating for volume changes and intracranial pressure