Endoscopic Optic Nerve Decompression Research Articles

How I do it - endoscopic endonasal optic nerve decompression for traumatic optic nerve neuropathy.

Traumatic optic neuropathy (TON) consists of damage to the optic nerve following head injury and affects about 0.5-5% of patients with closed head injuries. It is characterized by a sudden decrease in visual acuity and/or visual field loss. Surgical treatment is usually warranted when ongoing compression occurs at the level of the optic canal. We describe the technical nuances of endoscopic endonasal approach for compressive TON and add evidence supporting this approach as a valid option to treat this condition.

Sudden Blindness as the Only Symptom Caused by a Small Sphenoid Sinus Mucocele in a Young Child.

Background: Sphenoid sinus mucocele (SSM) represents a relatively rare disease among pediatric population as compared to adults, with a 1% to 3% incidence of all paranasal sinus mucoceles. Since the initial symptoms varied often, SSM caused blindness was scarcely seen. Case Presentation: Here we described an unusual case of small, isolated SSM causing acute visual loss in a 9-year-old girl. The patient first consulted an ophthalmologist for her right blindness. A diagnosis of SSM was suspected indicated by an orbital MRI scan. Thereafter the patient was referred to our department and an endoscopic sphenoidotomy and optic nerve decompression was performed. Surprisingly, her vision was relieved immediately after surgery, followed by dramatic improvement during the postoperative 20-month follow-up period. Conclusion: To our knowledge, a better understanding of SSM in pediatrics is essential for clinicians, including neurologists, ophthalmologists, and otolaryngologists to make early diagnoses and correct treatment by MRI and CT scan. Prompt surgical intervention of endoscopic transnasal sphenoidectomy is a quite safe, effective, and minimally invasive method for patients.

Surgical Intervention Outcome for Patients With Acute Vision Loss Due to Allergic Fungal Rhinosinusitis: A Systematic Review and Meta-Analysis.

Allergic fungal rhinosinusitis (AFRS) is a severe type of chronic rhinosinusitis (CRS) characterized by a high risk of acute vision loss resulting from the affection of optic nerves. This vision loss results from direct pressure upon the optic nerve by the sinus tissues and bone degradation. This is why early involvement of a professional is significant so as not to result in a permanent disability. This systematic review and meta-analysis will analyze the efficacy of surgical operations in enhancing visual outcomes in patients with acute vision loss due to AFRS. A systematic search was carried out based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using PubMed, Embase, Cochrane Library, and Scopus with the keywords "acute vision loss," "allergic fungal rhinosinusitis," and "surgical intervention." The studies included patients who developed AFRS-related acute vision loss, those assessing the outcomes of the surgical interventions, and those published in English. Two separate researchers extracted data and conducted quality assessments. The data synthesis process employed the R studio software (Posit, Boston, MA). The identified studies for the review constituted 12 and involved 320 patients. The mean pooled event rate regarding acute vision loss of AFRS patients was 33.1%. Ear, nose, and throat surgeries, including functional endoscopic sinus surgery (FESS) and optic nerve decompression, had a mean pooled success in vision recovery of 68%. Early treatment and utilization of other types of corticosteroids were utilized to enhance the results. Hence, early and proper surgery like FESS, optic nerve decompression, and corticosteroid treatment have better visual prognosis in AFRS patients. Standard early diagnosis and management guarantee the prevention of irreversible blindness, which stresses the need for an interdisciplinary approach and further studies.

Importance of Preoperative Pupillary Reflex in Traumatic Optic Neuropathy.

Traumatic optic neuropathy (TON) refers to a pathological condition caused by direct or indirect injury to the optic nerves. In the case of patients with traumatic brain injury, adequate vision evaluation is difficult in many cases due to altered mentality. In order to address this problem, we investigated preoperative pupillary light reflex in TON patients as a predictive factor of surgical outcomes after optic nerve decompression. From April 2020 to September 2022, we enrolled patients who were diagnosed with TON and underwent endoscopic optic nerve decompression at our institution. Vision and pupil reflex tests were performed by an ophthalmologist before and after surgery. Seven patients were enrolled. Their ages ranged from 9 to 78 years and all were male. Among the 7 patients, the patient whose pupillary light reflex was 6mm with sluggish and 7mm with fixated pupil before surgery showed no improvement in vision. Patients with some response to direct reflex or contralateral indirect reflex testing preoperative showed vision improvement postoperative. Direct and indirect pupillary reflexes can be important factors determining treatment for TON. In unconscious patients with a fracture involving the optic canal, timely surgical intervention based on pupillary reflex can prevent permanent loss of vision.

Salvaging Vision: A Study of Non-Traumatic Optic Neuropathies

Background and Objectives: Various ear, nose, and throat (ENT) conditions can result in vision loss. The purpose of this study is to identify the etiologies, presentations, and radiological findings associated with impaired vision in the context of ENT. Additionally, this article discusses management protocols, including optic nerve decompression and orbital decompression.Methods: In a retrospective study, we examined the period from 2016 to 2022 at a tertiary care hospital in Mumbai, India. The analysis included 11 patients who presented with progressive diminution of vision. All patients received a regimen of broad-spectrum intravenous antibiotics and high-dose intravenous steroids. This was followed by either endoscopic optic nerve decompression or orbital decompression. Subsequent improvements in vision were documented, and any complications were evaluated.Results: A total of 11 patients were treated with medical management followed by successful surgery, with 10 patients demonstrating significant vision improvement.Conclusion: Identifying the etiology of vision loss and managing the condition can present challenges for otorhinolaryngologists. A thorough grasp of the underlying pathophysiology, combined with active surveillance of clinical and radiological indicators, can enable these clinicians to achieve effective and rewarding outcomes.

Endoscopic endonasal optic nerve decompression in children younger than 2 years old with congenital optic canal stenosis: illustrative cases.

Congenital optic canal stenosis causing compressive optic neuropathy is a rare disorder that presents unique diagnostic and treatment challenges. Endoscopic endonasal optic nerve decompression (EOND) has been described for optic nerve compression in adults and adolescents but has never been reported for young children without pneumatized sphenoid sinuses. The authors describe preoperative and intraoperative considerations for three patients younger than 2 years of age with congenital optic canal stenosis due to genetically confirmed osteopetrosis or chondrodysplasia. Serial ophthalmological examinations, with a particular focus on object tracking ability, fundoscopic examination, and visual evoked potential trends in preverbal children, are important for detecting progressive optic neuropathy. The lack of pneumatization of the sphenoid sinus presents unique challenges and requires the surgical creation of a sphenoid sinus with the use of neuronavigation to determine the limits of bony exposure given the lack of easily identifiable anatomical landmarks such as the opticocarotid recess. There were no perioperative complications. EOND for congenital optic canal stenosis is safe and technically feasible even given the lack of pneumatization of the sphenoid sinus in young patients. The key operative step is surgically creating the sphenoid sinus through careful bony removal with the aid of neuronavigation. https://thejns.org/doi/10.3171/CASE23559.

Our Experience in Endoscopic Transnasal Optic Nerve Decompression

INTRODUCTION: Traumatic optic neuropathy (TON), a severe complication following head injury, affects about 0.5% to 5% of patients with closed head injuries.1 Visual acuity (VA) loss associated with TON can be partial or complete and temporary or permanent. Increased intracanalicular pressure after an injury is considered to be one of the main pathophysiological manifestations.2 Mucoceles involving the Onodi cell and the sphenoidal sinus are rare, and optic nerve compression with decreased visual acuity may be the first presenting symptom.3. Endonasal endoscopic optic nerve decompression is a safe and highly effective treatment to reduce the hydrostatic pressure on the optic nerve in cases of optic neuropathies of various etiologies. This is to share our experience on transnasal endoscopic optic nerve decompression done for optic neuropathy due to traumatic optic neuropathy and non-traumatic optic neuropathy. CASE SERIES: A case series of three patients with traumatic optic neuropathy and one patient with non-traumatic optic neuropathy over a period of two years were studied. All four patients underwent endoscopic transnasal optic nerve decompression and surgical outcome in terms of visual recovery was observed. DISCUSSION: Endoscopic transnasal optic nerve decompression is a minimally invasive , safe and efficient method of treatment for traumatic and non-traumatic optic neuropathy .4 Our experience also suggest that surgical intervention need to be considered as early as possible especially for traumatic cases to enhance visual recovery.

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

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. 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. 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. 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.

Surgical management of pseudotumor cerebri syndrome: A single center experience with endoscopic optic nerve decompression and CSF diversion procedures

ObjectivesPseudotumor cerebri syndrome (PTC) is a chronic disorder, which is initially treated by conservative measures, yet surgery is inevitable in case of progressive worsening of vision or headache despite medical treatment. The surgical management is controversial including CSF diversion procedures and optic decompression. The purpose of this study was to evaluate the efficacy of different surgeries in PTC and to present surgical outcomes in a single center. MethodsThis retrospective study included the patients with PTC who were operated by endoscopic optic nerve decompression (EOND), ventriculoperitoneal (VP) and lumboperitoneal (LP) shunting. Surgical outcomes, i.e. visual acuity, visual field, papilledema and headache were compared according to type of surgery. Surgical complications were noted. ResultsSeventeen of 36 patients were treated with shunting, 14 with EOND and 5 patients with both EOND and shunting. No statistical significance was observed between CSF diversion procedures and EOND concerning clinical outcomes. The improvement rate of papilledema was higher with VPS (p = 0574) while more patients benefitted from LPS regarding visual field and acuity (p = 0471 and p = 0718, respectively). The best treatment response for headache was in shunt implemented patients (VPS and LPS) with a rate of 88.2% followed by EOND (78.6%) and both surgeries (60%)(p = 0.294). Gender and BMI were significant predictors of improved papilledema (p = 0.034). ConclusionsOur study demonstrated comparable results between shunting and EOND, regarding the efficacy on surgical outcomes. EOND is quite effective for headache besides its advantage on treatment-refractory visual loss. Shunting may offer sustained relief of symptoms when compared with EOND.

Endonasal Endoscopic Optic Canal Decompression for Nontraumatic Optic Neuropathy: Long-Term Visual Outcomes in 36 Patients

Background: The management of compressive optic neuropathy (CON) arising from nontraumatic compression of the optic nerve within the optic canal (OC) remains a topic of controversy. In this study, our aim was to assess the effectiveness and safety of endonasal endoscopic optic nerve decompression (EEOND). In addition, we conducted an analysis of prognostic factors that could potentially influence visual outcomes. Methods: This retrospective cohort study was conducted between January 2015 and December 2021, involving adult patients (age > 18) diagnosed with CON and treated with EEOND at our specialized skull base expert center. The study evaluated the impact of surgery on visual acuity (VA), mean deficit (MD), and foveal threshold (FT) of the visual field (VF). These parameters were assessed preoperatively and at 3- and 12-month postoperative follow-ups. The relationship between clinical variables and the differences in postoperative to preoperative VA, MD, and FT of the visual field was analyzed through univariate and multivariate approaches. Results: Thirty-six patients (38 eyes) were included, with a mean age of 52 (±12) years, and a female predominance (78%). The mean ophthalmologic follow-up duration was 38 (±32) months. At the 12-month follow-up, 39% of the patients exhibited a VA improvement of ≥0.2 LogMAR. Partial VF improvement (MD improvement ≥25%) was observed in 55% of the patients, whereas 19% experienced complete recovery. In multivariate analysis, the presence of a type 4 OC was identified as the sole negative prognostic factor for visual improvement (VA and VF) at 12 months. Six patients (17%) encountered minor surgical complications, all of which were managed conservatively and had no impact on visual outcomes. Conclusions: Our study demonstrates that EEOND is a safe and effective procedure, even in cases of severe and long-lasting CON caused by nontraumatic compression of the optic nerve at the level of the OC.

Surgical Outcome in Patients with Traumatic and Atraumatic Optic Neuropathy Following Endoscopic Optic Nerve Decompression.

Endoscopic optic nerve decompression is a highly effective and reliable approach for patients with select cases of optic neuropathy. It reduces the hydrostatic pressure and helps in relieving the compressive forces within the intracanalicular portion of the optic nerve consequently preserving and arresting the deterioration of vision. The advantages of the endoscopic approach over other procedures include preservation of olfaction, quick recovery, lack of external scars and less morbidity. The objective of the study isto assess the surgical outcome of endoscopic optic nerve decompression in patients with traumatic and atraumatic optic neuropathy. The case records of consequent patients attending ENT department with defective vision due to traumatic and atraumatic causes were reviewed. The outcome was measured in terms of improvement in visual acuity by log MAR scale. Among the 14 patients studied, 57% were females and the median age of presentation was 33 years. As compared to preoperative baseline visual acuity, the overall improvement was achieved in 11 patients, with an effective rate of 78.5% postoperatively. Patients presenting with no light perception and residual vision had significant improvement in visual acuity after surgery. Trans-nasal endoscopic surgery helps in decompressing the optic nerve with proper exposure of the orbital apex and optic canal without any intracranial or intra-orbital complications. Further, being a minimally invasive procedure has great advantage in cases of optic neuropathy.

Endoscopic Endonasal Optic Nerve Decompression in Idiopathic Intracranial Hypertension: When to Implement Optic Nerve Sheath Fenestration.

Idiopathic intracranial hypertension (IIH) is a syndrome characterized with increased intracranial pressure and normal cerebrospinal fluid (CSF) composition. Treatment is mainly conservative, whereas CSF diversion surgery is the most frequently used surgical intervention. Endoscopic endonasal optic nerve decompression (EOND) is a newer surgical treatment of this patient group. This study presents a single clinic's case series with comparative results of unilateral an bilateral EOND with or without optic nerve fenestration. Sixteen patients with IIH syndrome who underwent 18 EOND procedures by a single neurosurgeon were evaluated with MRI and digitally subtracted angiography preoperatively. Both preoperative and postoperative visual acuity and perimetry and fundoscopy examinations were routinely performed. All patients underwent sphenoidotomy using the endoscopic binostril approach; however, unilateral or bilateral optic nerve decompression and accompanying optic sheath fenestration was determined on a case-by-case basis, after which all patients were also evaluated for the outcome of headaches. Most of the patients were female, and the mean age was 30.28 ± 9.78 years. CSF pressure was increased in all patients (406.43 ± 112.91 mm of H 2 O), and the follow-up period was 61.72 ± 21.67 months. In patients with unilateral EOND, visual fields improved in 83%, visual acuity in 70%, headache in 75%, and papilledema in 27% of cases. In patients with bilateral EOND, perimetry improved in 86%, visual acuity in 43%, headache in 50%, and papilledema in 57% of cases. EOND is an effective surgical option in the treatment of IIH. Bilateral decompression is preferable in patients with bilateral visual involvement, and optic nerve fenestration may prove to be helpful in patients with IIH whose primary complaint is headache.

Diagnosis and treatment of transnasal endoscopic optic canal decompression for traumatic optic neuropathy.

To investigate the clinical efficacy and prognostic factors of transnasal endoscopic optic decompression in the treatment of traumatic optic neuropathy (TON). A retrospective analysis was performed on 13 TON patients in The Seventh Affiliated Hospital of Sun Yat-sen University and Shenzhen Eye Hospital in Shenzhen City (China) from June 2020 to April 2022. These patients had received transnasal endoscopic optic decompression, and hormonal and neurotrophic drugs were given after surgery. Visual acuity (VA) improvement was used as the criterion to judge clinical efficacy. In a total of 13 patients, 13 injured eyes (12 men and 1 woman; mean age, 28.0 ± 11.8 years) received transnasal endoscopic optic decompression. After surgery, nine patients had improved VA, whereas four patients failed to show any improvement, resulting in a total effective rate of 69.2%. Of the six patients with no light perception preoperatively, three had effective results after the operation, giving an effective rate of 50.0%. Of the seven patients with residual light sensation preoperatively, six had effective results after the operation, giving an effective rate of 85.7%. Of the 10 patients operated on within 7 days after injury, seven had effective results, giving an effective rate of 70%. Of the three patients injured and operated on after 7 days, two had effective results, giving an effective rate of 66.7%. Transnasal endoscopic optic nerve decompression is an effective treatment method for TON. The presence of residual light perception and the timing of surgery within 7 days are crucial to the prognosis.

Endoscopic endonasal optic nerve decompression: treatment of fibrous dysplasia in a pediatric population.

Patients with fibrous dysplasia (FD) of the anterior skull base can experience progressive visual loss and impairment. The authors reviewed their experience with endonasal decompression of the optic nerve (ON) in this patient population. Endoscopic ON decompression (EOND) is a feasible surgical approach for children with FD and visual deficit due to structural ON compression. Electronic medical records of children between 1 and 17 years of age with unilateral FD of the anterior skull base and concomitant ON compression, who required EOND between 2017 and 2022 (n = 4), were reviewed for demographic data, both pre- and postoperative imaging, and evaluations by an otolaryngologist, neurosurgeon, and ophthalmologist in a multidisciplinary fashion. EOND was found to be a safe and effective surgery for children with FD. Visual acuity was stable in 80% of the eyes postoperatively. Visual fields improved in 40% of the eyes and remained stable in the rest. EOND is beneficial for progressive optic neuropathy that is unresponsive to steroid therapy and can prevent permanent disability if performed prior to irreversible damage to the nerve. EOND can decompress the edematous ON with proper exposure of the optic canal and orbital apex, without any major complications.

Lateral optico-carotid recess as an anatomical landmark for optimal endoscopic optic nerve decompression

Lateral optico-carotid recess as an anatomical landmark for optimal endoscopic optic nerve decompression

Efficacy and prognostic factors of endoscopic optic canal decompression in children with traumatic optic neuropathy

Objective: To explore the efficacy and prognostic factors of endoscopic optic canal decompression in children with traumatic optic neuropathy (TON). Methods: The clinical data of 47 children with TON treated with endoscopic optic nerve decompression in the Department of Neurosurgery of Beijing Tongren Hospital from November 2010 to October 2021 were retrospectively analyzed, and the visual acuity before and after treatment was compared. The clinical factors were taken as independent variables, and visual improvement was taken as dependent variable for multivariate Cox regression analysis to observe the factors that may affect the efficacy. Results: There were 47 patients in this study, including 35 males and 12 females, and the age ranged from 3.0 to 12.0 (7.2±2.3) years. After surgery and hormone treatment, 28 (59.6%) cases obtained visual improvement. Univariate analysis showed that the improvement rate of visual acuity in patients with residual vision after injury was higher than that in patients without vision [85.0% (17/20) vs 40.7% (11/27), P=0.002], while the improvement rate of visual acuity in patients with dislocated optic canal fracture was lower than that in those without fracture [42.1% (8/19) vs 71.4% (20/28), P=0.044]. The improvement rate of visual acuity in patients with operation time interval ≤7 d was higher than that in patients with operation time interval>7 d [80.8% (21/26) vs 33.3% (7/21), P=0.001]. Multivariate Cox regression analysis showed that post-traumatic residual visual acuity (HR=3.805, 95%CI: 1.087-13.318, P=0.037) and operation time interval≤7 d (HR=2.883, 95%CI: 1.084-7.662, P=0.034) were protective factors for post-surgical visual acuity. Conclusions: Endoscopic optic nerve decompression can effectively improve the visual acuity of children with TON. Post-traumatic residual visual acuity and operation time interval ≤7 d are independent protective factors for post-surgical visual acuity.

Endoscopic Optic Nerve Decompression for Direct Traumatic Optic Neuropathy : Our 10 Years Experience.

Traumatic optic neuropathy (TON) can be classified into direct or indirect types. Direct optic injury usually results from optic nerve avulsion ,laceration or compression by fracture, fracture segment impingement or a resultant hematoma. Indirect optic injury is caused by increased intracanalicular pressure resulting in ischemia and disruption of neurofeedback channels. The prognosis of TON is usually quite poor. To date, no standardized treatment protocol has been developed for TON. In this study we are assessing the visual improvement in patients with direct TON who underwent endoscopic optic nerve decompression in the last 10 years. A retrospective study of 32 cases of optic nerve decompression for direct TON in the last 10 years. Preoperative and postoperative visual assessment were done and followed up for 3 months. There was complete improvement in vision in 17% of patients when optic nerve decompression was done within 72h of trauma; whereas 31% cases had only partial improvement when done between 3 and 7 days. And there was no improvement when done after 7 days. Endoscopic optic nerve decompression is a minimally invasive surgery for direct traumatic optic neuropathy; with minimal or no complications when done by an experienced ENT surgeon. Other important prognostic factors include timing of surgery and preoperative visual status.

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.

A novel adaptation of endoscopic optic nerve decompression in non-traumatic optic neuropathy: A retrospective case series.

A novel adaptation of endoscopic optic nerve decompression in non-traumatic optic neuropathy: A retrospective case series.

Management Strategies of Fibrous Dysplasia Involving the Paranasal Sinus and the Adjacent Skull Base.

Current management of fibrous dysplasia (FD) involving the paranasal sinuses and the adjacent skull base is currently controversial. This study aims to present our experience in the management strategy of FD that involves the paranasal sinuses and the adjacent skull base. Twenty three patients from 2006 to 2019 with monostotic fibrous dysplasia (MFD), polyostotic fibrous dysplasia (PFD), or McCune-Albright syndrome (MAS) involving the paranasal sinuses and the adjacent skull base were retrospectively reviewed. This study series was divided into 3 groups based on management strategies: the observation group, the surgery group, and the optic nerve decompression group. The observation group included 9 patients with asymptomatic MFD with stable condition during the follow-up period of 15 to 164 months. The surgery group included 10 symptomatic patients with MFD who had personalized endoscopic endonasal surgery. The symptoms of the patients were relieved after surgery. The optic nerve decompression group included 4 patients with visual loss, who underwent endonasal endoscopic optic nerve decompression (EOND) with the aid of image-guided navigation. Their vision improved after surgery. Clinical observation and periodic computed tomography (CT) scan are adopted for asymptomatic patients. Surgery is indicated in symptomatic patients. Optic nerve decompression is recommended as soon as possible if the patient has visual loss, whereas prophylactic decompression is not recommended if the optic nerve is encroached by FD without visual loss. Navigation plays an important role in endoscopic surgery involving the paranasal sinuses and the adjacent skull base, especially in FD resection and optic nerve decompression.