The Role of Endonasal Endoscopic Optic Nerve Decompression as the Initial Management of Primary Optic Nerve Sheath Meningiomas

Gross-total resection in optic nerve sheath meningiomas: minimally invasive and cosmetic pleasing

PURPOSE

The optic nerve sheath meningioma (ONSM) is one of the most challenging tumors in orbital surgery. From the perspective of mental health and patient needs, we analyzed the necessity and importance of the endoscopic transnasal approach (ETA) combined with optic nerve transection (ONT) in gross-total resection (GTR) in ONSM patients with residual vision and aim to broaden the use of ONT for specific people.

METHODS

The authors included patients with ONSMs who were treated between 2014 and 2022. We divided those cases into two groups named ETA group and lateral orbitotomy approach (LOA) group. We present the application of ETA and analyze the preoperative indication of the ONT and compared the advantages and disadvantages between ETA and LOA. The degree of tumor resection was based on imaging and surgical evaluation.

RESULTS

A total of 23 patients with ONSM were included. Sixteen patients underwent ETA, and seven underwent LOA. Among ETA cases, GTR was achieved in 14 patients with ONT and most patients maintained normal eye movement function (75%) and morphology (93.75%). In the ETA group, 14 patients experienced vision loss, while two other patients saw improvements in vision. And proptosis was alleviated (5.20 ± 2.34 vs 0.27 ± 0.46, p < 0.0001). Six patients with blindness and proptosis of the LOA group resulted in GTR with ONT and ophthalmectomy. Although intracranial extension and recurrence included no cases in the two groups, a significant psychological gap was presented due to cosmetic problems.

CONCLUSIONS

Under the premise of reducing damage and improving aesthetics, the selection of ETA combined with ONT to gross-total resect ONSMs successfully provides a minimally invasive access with acceptable complications. As an important adjunct to GTR in the surgical treatment of ONSM, the scope of ONT application should be expanded to relieve the patient's psychological burden.

Treatment of Meningiomas Involving the Optic Canal with Endoscopic Transnasal Decompression of the Optic Nerve

BACKGROUND

Management of patients with optic nerve sheath meningiomas (ONSMs) is controversial and the treatment strategy in this patient group is still up for discussion. Transnasal endoscopic orbital and optic nerve decompression aims to reduce the pressure in the orbit and on the optic nerve and thereby prevent vision loss. This article presents material from 7 cases of transnasal endoscopic orbital decompression.

METHODS

The study design is a retrospective cohort study. The aim was to include all patients with a meningioma residing along the nerve sheath and who were operated using endoscopic transnasal decompression of the orbit and if needed the optic canal at Odense University Hospital. Data from the medical records were collected and pre- and postoperative eye examinations were compared. In addition, it was recorded whether there were complications to the procedure and whether additional treatments were given.

RESULTS

In total, 4 women and 3 men were included in the study. Four out of 7 patients experienced improvement in vision after the operation. One patient experienced unchanged vision and 2 patients experienced deterioration of vision after surgery.

CONCLUSIONS

The current report of 7 patients with ONSM shows promising results for this surgical procedure as 4 out of 7 patients experienced improvement in their vision at follow-up examinations. The 2 patients who experienced deterioration of vision already had severely reduced vision preoperatively, which indicates that surgery should be considered before the vision becomes significantly reduced.

Endoscopic endonasal optic nerve sheath decompression (EONSD) for idiopathic intracranial hypertension: Technical details and meta-analysis

BACKGROUND

The neurosurgical management of idiopathic intracranial hypertension (IIH) remains controversial. Although shunting and newer endovascular stenting techniques are part of the neurosurgical armamentarium to treat medically refractory IIH symptoms, optic nerve sheath fenestration has traditionally been performed by ophthalmologists.

OBJECTIVE

We present a detailed cadaveric dissection that simulates the endoscopic endonasal optic nerve sheath decompression (EONSD) technique along with the literature review.

METHODS

EONSD was performed in four freshly injected cadaveric specimens. Additionally, a systematic review from different electronic databases has been done.

RESULTS

Bilateral EONSD was performed in all specimens without significant technical difficulties. Based on our experience, there is no need to expose the periorbita or orbital apex. The primary anatomic landmarks were the optic canal, the lateral opticocarotid recess, the tuberculum, the limbus, and the clinoid segment of the internal carotid artery. Based on the systematic review, 68 patients (77.9% female) underwent EONSD, with a mean age of 33.4 ± 6.9 years in adult patients. Follow-up ranged from 3 to 58 months across different studies. The pooled meta-analysis showed headache, papilledema, and visual disturbance improvement in 78% [95%CI 0.65-0.90], 72% [95%CI 0.61-0.83], and 88% [95%CI 0.80-0.96] of cases who underwent EONSD, respectively. The subgroup analysis showed there was no statistically significant difference between unilateral and bilateral EONSD in terms of different measured outcomes.

CONCLUSION

EONSD is a feasible surgical procedure that may obviate the need for shunting in patients with IIH. Although clinical studies showed that EONSD is a safe and effective technique, further studies are required to establish the preferences of either unilateral or bilateral approaches.

The use of an endoscopic endonasal approach for a secondary intraorbital meningioma: illustrative case

BACKGROUND

Meningiomas are the most frequent primary tumors in the central nervous system (CNS), but intraorbital location is uncommon and accounts for only 0.2% to 4% of all CNS meningiomas. Lesions in this compartment could be classified as primary, secondary, or ectopic. The close relationship with the optic nerve sheath is a landmark to identify the tumor as primary, whereas secondary tumors commonly come from an extension of an intracranial meningioma, and ectopic meningioma is a concept not yet completely established.

OBSERVATIONS

The authors present a rare case of a secondary intraorbital meningioma operated through an endoscopic endonasal approach. Secondary meningiomas at the medial orbit are very uncommon, given their more common superior and lateral location as an extension of sphenoid meningiomas. The endoscopic endonasal route provides direct access to the medial orbit. The authors present an illustrative case of a meningioma located at the medial orbit and resected through an endoscopic endonasal approach that provided excellent visualization and anatomical exposure. Additionally, the authors review the concept and possible similarities between secondary and ectopic intraorbital meningiomas.

LESSONS

An endoscopic endonasal approach should be considered as a feasible treatment option for intraorbital meningiomas, especially if they are in the medial orbital wall.

Does Endoscopic Transnasal Optic Nerve Decompression Followed by Radiosurgery Improve Outcomes in the Treatment of Parasellar Meningiomas?

Introduction: The clinical management of parasellar meningiomas (PM) is challenging due to their intimate association with critical neurovascular structures. Consensus regarding the recommended treatment protocol is lacking. This study will evaluate patients’ visual outcomes following endoscopic transnasal optic nerve decompression (ETOND) and will investigate the possibility of reducing the rate of complications associated with stereotactic radiosurgery (SRS). Methods: Retrospective analysis was conducted on all patients who underwent ETOND for PM between 2013 and 2020. The study comprised 12 patients (7 women and 5 men aged 36–75 years; mean, 55.2 years; median, 57.6 years) in which 14 optic nerve decompression procedures were carried out. Patients were followed up for 6 to 86 months (mean, 29.3 months; median, 25 months). There were five cases of spheno-orbital meningioma, four cases of cavernous sinus meningioma, and one case each of petro-clival meningioma, optic nerve sheath meningioma, and planum sphenoidale/tuberculum sellae meningioma. Visual outcome was evaluated and any postoperative complications noted. Results: Improvements in visual acuity were noted in 10 of 14 eyes (71.4%) 3 to 6 months postoperation. Visual acuity remained stable in the remaining four eyes. No deterioration of visual acuity was noted during the follow-up period. In total, 9 of the 12 patients underwent SRS. No tumor growth was determined, while reduction in tumor volume was noted in five patients following SRS. No complications associated with SRS or the surgical procedure were noted. Conclusions: ETOND appears to be a promising technique for increasing rates of improved visual function, while reducing the risk of post SRS-related complications. In combination with subsequent SRS, it is an ideal treatment modality in the management of parasellar meningiomas. Confirmation of our findings would require a larger, prospective multicenter study.

Radiotherapy and Radiosurgery in the Management of Optic Nerve Sheath Meningiomas: An International Systematic Review and Meta-Analysis of Twenty Studies

BACKGROUND

Optic nerve sheath meningiomas (ONMs) are often managed with radiotherapy (RT) with the goal of achieving radiographic local control (LC) and preventing deterioration of visual acuity (VA). We aimed to perform a systematic review and meta-analysis of outcomes for patients with ONM treated with RT.

METHODS

The PICOS/PRISMA/MOOSE selection criteria were used to identify studies. Primary outcomes were stable or improved VA and radiographic LC at last follow-up. The secondary outcomes were incidences of radiation-induced retinopathy and xerophthalmia and stable or improved visual fields (VFs). Weighted random-effects meta-analyses using the DerSimonian and Laird methods were conducted to characterize effect sizes. Mixed-effects regression models were used to examine potential correlations between gross tumor volume (GTV) and outcomes.

RESULTS

In total, 444 patients with ONM across 20 published studies were included. The estimated LC rate was 99.8% (95% confidence interval [CI], 98.3%-100%), and the estimated proportion of patients with stable or improved VA or VF was 89.7% (95% CI, 86.2%-92.4%) and 93.3% (95% CI, 89.5%-95.8%), respectively. Estimated incidences of radiation-induced retinopathy and xerophthalmia were 7.2% and 10.1%, respectively. GTV was significantly associated with VA (P = 0.014) with estimated VA rates of 96.4%, 91.4%, and 80.5% for GTVs of 2.0, 3.0, and 4.0 cm³, respectively.

CONCLUSIONS

RT was well tolerated, with excellent LC achieved. Nearly 90% of patients noted either stability or improvement in VA and VF. Larger ONMs were associated with poorer VA.

Optic nerve injury in preoperative imaging is associated with visual improvement outcome in endoscopic optic nerve decompression

Objective

To evaluate potential clinical parameters having an impact on visual outcome after endoscopic optic nerve decompression in acute optic neuropathy patients.

Methods

A retrospective chart review of patients with acute optic neuropathy, who underwent endoscopic optic nerve decompression between June 2001 and November 2018 at an academic center was performed. Patients were divided into groups according to visual improvement after surgical treatment (yes/no). Following clinical parameters were compared between groups: perioperative steroid use, evidence of optic nerve affection in preoperative neuroimaging, additional optic nerve sheath incision, surgery delay and preoperative C-reactive protein (CRP) levels. Further subgroups analyses were conducted based on etiology (trauma/tumor).

Results

Among 32 included cases, 16 patients (50%) reported visual improvement after endoscopic optic nerve decompression. There was no significant difference in visual improvement between etiology subgroups (trauma: n = 9/20 (45%) vs. tumor: n = 7/12 (58.3%), p = 0.465). Tumor subgroup patients with visual improvement had a significantly higher prevalence of optic nerve affection in preoperative neuroimaging than those without visual improvement (p = 0.018, φ = 0.683). Perioperative steroid administration was negatively associated with visual outcome (p = 0.034, φ = 0.375). Nerve sheath incision, surgery delay and preoperative CRP levels did not have a significant impact on visual outcome (p > 0.05).

Conclusion

Radiological findings can help as an indicator for surgical treatment since an affected optic nerve in preoperative neuroimaging resulted in better visual outcome after surgery. The use of steroids should be considered more carefully since it did not show any beneficial effect.

Primary and Secondary Optic Nerve Sheath Meningioma

Objective  This study was aimed to review issues relating to the recognition, radiographic diagnosis, monitoring, and management of primary and secondary optic nerve sheath meningioma (ONSM). Design  This study is a review of peer-reviewed literature combined with illustrative case studies. Participants and Methods  A literature search was conducted via the PubMed database using pertinent search terms. Selected articles were limited to those written or translated into English. Additional works cited within articles were also included. Individual cases were drawn from the experience of a tertiary academic neuroophthalmic and orbital practice. Tables summarize radiotherapeutic and surgical studies, excluding single case reports and studies focusing on meningioma of intracranial origin. Main Outcome Measurements  Review of reported surgical and radiotherapeutic series is the primary measurement. Results  The natural history of optic nerve sheath meningiomas is primarily characterized by progressive ipsilateral vision loss. Diagnosis is typically based on radiographic imaging findings, with biopsy remaining indicated in some patients. Management strategies may include observation, radiation, and/or surgical intervention, or a combination of these approaches. The role of surgery, especially with respect to primary ONSM (pONSM), remains controversial. Advancement of radiotherapy techniques has shifted modern treatment paradigms in pONSM toward radiation as primary treatment, as surgical outcomes are inferior in major studies. Although radiation remains the treatment of choice in many cases, selected patients may benefit from surgery, especially in the setting of secondary ONSM (sONSM). Conclusion  A wide variety of radiotherapeutic and surgical treatment modalities for ONSM exist. The specific indications for each management strategy continue to be redefined.

Optic nerve sheath meningioma

PURPOSE OF REVIEW

Optic nerve sheath meningiomas (ONSMs) are rare benign tumors of the anterior visual pathway which present with slowly progressive and painless vision loss and account for approximately 2% of all orbital tumors. This article provides an overview as well as an update on the ONSMs with regards to cause, epidemiology, clinical presentation, diagnosis, and management in adults and pediatric population.

RECENT FINDINGS

The clinical presentation and prognosis of ONSMs can vary and largely depend on the location of tumor as well as the histologic type. Overall, the diagnosis is based on clinical presentation, examination, and neuroimaging findings. Nevertheless, delays in diagnosis or misdiagnosis are not uncommon and can result in higher morbidity rates. Recent advances in diagnostic as well as more effective and less-invasive treatment options are discussed in this review.

SUMMARY

ONSMs are a rare cause of slowly progressive and inexorable visual loss. Although ONSM diagnosis depends on the characteristic clinical and radiologic findings, prompt diagnosis, and appropriate management is critical for favorable visual outcomes. Thus, current focus is optimizing diagnostic as well-treatment methods for patients with ONSMs.