Visual outcomes comparing surgical techniques for management of severe idiopathic intracranial hypertension

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

OBJECTIVES

Pseudotumor 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.

METHODS

This 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.

RESULTS

Seventeen 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).

CONCLUSIONS

Our 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.

Stenting versus medical treatment for idiopathic intracranial hypertension: a matched-control study

BACKGROUND

This prospective cohort study compared the outcomes of stenting and medical treatment for patients with idiopathic intracranial hypertension (IIH) and venous sinus stenosis (VSS).

METHODS

In this single-center cohort study, patients with IIH and VSS were evaluated between January 2014 and December 2019 with follow-up periods of 1, 3, and 6 months. The patients received either stenting or medical treatment. The two groups underwent 1:1 matching using propensity score analysis, and the clinical outcomes were compared.

RESULTS

Following 1:1 matching, 36 patients who underwent stenting and 36 who underwent medical treatment were matched. The median improvements in the papilledema Frisén grade were greater in the stenting group at 1 month (-2 vs 0), 3 months (-3 vs -1), and 6 months (-3 vs -1) than in the medical treatment group. Patients who received stenting treatment had a significantly higher prevalence of complete resolution of their respective symptoms (headache, tinnitus, or visual disturbances) at 3 months (58.3% vs 13.9%, OR 8.68, 95% CI 2.74 to 27.52) and 6 months (80.6% vs 22.2%, OR 14.50, 95% CI 4.64 to 45.32) than those receiving medical treatment.

CONCLUSIONS

This matched-control study shows that stenting has a greater efficacy rate and rapid resolution of papilledema and its respective symptoms compared with medical treatment.

Venous sinus stenting for idiopathic intracranial hypertension patients with functioning ventriculoperitoneal shunts: A case series

Idiopathic intracranial hypertension (IIH) is a disease defined by increased intracranial pressure and associated with a variety of symptoms ranging from headaches to tinnitus. Ventricular peritoneal shunting has been the mainstay treatment for patients with IIH. Although VPS's have shown efficacy in treating IIH, some patients complain of refractory symptoms even with functioning VPS's. Venus stenting has emerged as a new technique for treating these refractory symptoms. Despite the scarce literature pertaining its efficacy and safety profile, several small studies have shown promising results. In this case series, four patients with IIH complained of refractory symptoms despite functioning VPS's and were treated with venous stenting.

Optic atrophy secondary to minocycline-induced idiopathic intracranial hypertension

An early adolescent female presented with blurry vision, ocular 'fullness', pulsatile tinnitus and gait difficulty due to poor vision. She was found to have florid grade V papilloedema, 2 months after the use of minocycline for the treatment of confluent and reticulated papillomatosis for 2 months. MRI of the brain without contrast showed fullness of the optic nerve heads concerning for increased intracranial pressure, which was confirmed on lumbar puncture with an opening pressure greater than 55 cm H2O. She was initially started on acetazolamide, but due to high opening pressure and severity of visual loss, a lumboperitoneal shunt was placed in 3 days. This was complicated by a shunt tubal migration 4 months later, leading to worsening vision of 20/400 in both eyes for which she underwent shunt revision. By the time she presented to the neuro-ophthalmology clinic, she was legally blind with her exam consistent with bilateral optic atrophy.

Optic nerve sheath fenestration: Current status in France and comparison of 6 different surgical approaches

PURPOSE

Optic nerve sheath fenestration (ONSF) is a surgical procedure commonly performed in the Anglo-Saxon countries for the treatment of medically refractory idiopathic intracranial hypertension (IIH). We chose to compare 6 different trans-orbital surgical approaches to ONSF. We also desired to determine the number of optic nerve decompression procedures performed in France in 2019 and 2020.

METHODS

Four fresh frozen orbits were dissected at the University of Nice anatomy laboratory. We performed the following surgical approaches: (i) eyelid crease, (ii) lid-split, (iii) medial transconjunctival with medial rectus disinsertion, (iv) medial transconjunctival without rectus disinsertion, (v) lateral transconjunctival and (vi) lateral orbitotomy. For each surgical approach, we measured the distance between the incision and the optic nerve dura mater. We also extracted data from the French National PMSI (Programme de Médicalisation des Systèmes d' Information) database from January 2019 through December 2020 to determine the annual number of optic nerve decompression procedures.

RESULTS

The lid crease and medial transconjunctival approaches provided the shortest distance to the optic nerve (average 21mm and 24mm, respectively) and the lowest levels of difficulty compared to the other surgical routes. A total of 23 and 45 optic nerve decompressions were performed in France in 2019 and 2020, respectively. Among them, only 2 and 7 procedures, respectively, were performed through a trans-orbital approach.

CONCLUSION

Upper lid crease incision and medial transconjunctival approaches are the most direct and easiest surgical routes when performing an ONSF. We found that ONSF was rarely performed in France. We strongly recommend close cooperation between ophthalmologists, neurologists, neurosurgeons and interventional radiologists.

Idiopathic Intracranial Hypertension and Endoscopic Optic Nerve Sheath Fenestration

Idiopathic intracranial hypertension (IIH), also called as benign intracranial hypertension is a disorder, which is  considered benign in its course except its' ill effects on vision. Ocular findings in IIH such as papilledema, macular changes, retinal micro haemorrhages, cotton wool spots and tortuosity of vessels are the prominent features in funduscopy examination in these patients. Papilledema is a hallmark feature for evaluation of response to treatment. Ophthalmological rescue is a primary goal of management of idiopathic intracranial hypertension. Among the treatment options described in literature, optic nerve sheath fenestration is a minimally invasive endoscopic technique for the rescue of vision. We present this case-report, which will help ophthalmologists and the surgeons to determine the significance of the funduscopy changes after optic nerve sheath fenestration and help in decision making.

Visual recovery after unilateral optic nerve sheath fenestration for pseudotumor cerebri syndrome

PURPOSE

To evaluate the effect of optic nerve sheath fenestration (ONSF) on the rate of visual function improvement in patients with pseudotumor cerebri syndrome (PTCS).

METHODS

Retrospective chart review of patients with PTCS who underwent ONSF between 1998 and 2017. Visual function was evaluated by evaluating visual field (VF), mean deviation (MD), retinal nerve fiber layer (RNFL) thickness, papilledema grade, and visual acuity (VA) prior to and after ONSF.

RESULTS

Seventeen female patients aged 17 to 36 years underwent unilateral ONSF. Follow-up averaged 40.1 months. VF MD improved steadily in both eyes up to 12 months. Average RNFL thickness improved in the operated eye from 347 ± 166 mm to 92 ± 27 mm (p < .001) and the non-operated eyes from 306 ± 165 mm to 109 ± 46 mm (p < .001). The grade of papilledema improved in the operated eye from 3.3 ± 1.3 to 0.3 ± 0.7 and the non-operated eye from 3.0 ± 1.6 to 0.18 ± 0.4. There was an exponential rate of improvement in papilledema and RNFL thickness, with the greatest improvement occurring within the first 30 days. Average visual acuity remained intact in both eyes before and after surgery.

CONCLUSIONS

ONSF in appropriately selected patients leads to rapid improvement in papilledema and a steady recovery in VF.

A New Perspective on the Pathophysiology of Idiopathic Intracranial Hypertension: Role of the Glia-Neuro-Vascular Interface

Idiopathic intracranial hypertension (IIH) is a neurological disease characterized by symptoms and signs of increased intracranial pressure (ICP) of unknown cause. Most attention has been given to the role of cerebrospinal fluid (CSF) disturbance and intracranial venous hypertension caused by sinus vein stenosis. We previously proposed that key pathophysiological processes take place within the brain at the glia-neuro-vascular interface. However, the relative importance of the proposed mechanisms in IIH disease remains unknown. Modern treatment regimens aim to reduce intracranial CSF and venous pressures, but a substantial proportion of patients experience lasting complaints. In 2010, the first author established a database for the prospective collection of information from individuals being assessed for IIH. The database incorporates clinical, imaging, physiological, and biological data, and information about treatment/outcome. This study retrieved information from the database, asking the following research questions: In IIH subjects responding to shunt surgery, what is the occurrence of signs of CSF disturbance, sinus vein stenosis, intracranial hypertension, and microscopic evidence of structural abnormalities at the glia-neuro-vascular interface? Secondarily, do semi-quantitative measures of abnormal ultrastructure at the glia-neurovascular differ between subjects with definite IIH and non-IIH (reference) subjects? The study included 13 patients with IIH who fulfilled the diagnostic criteria and who improved following shunt surgery, i.e., patients with definite IIH. Comparisons were done regarding magnetic resonance imaging (MRI) findings, pulsatile and static ICP scores, and immune-histochemistry microscopy. Among these 13 IIH subjects, 6/13 (46%) of patients presented with magnetic resonance imaging (MRI) signs of CSF disturbance (empty sella and/or distended perioptic subarachnoid spaces), 0/13 (0%) of patients with IIH had MRI signs of sinus vein stenosis, 13/13 (100%) of patients with IIH presented with abnormal preoperative pulsatile ICP [overnight mean ICP wave amplitude (MWA) above thresholds], 3/13 (23%) patients showed abnormal static ICP (overnight mean ICP above threshold), and 12/13 (92%) of patients with IIH showed abnormal structural changes at the glia-neuro-vascular interface. Comparisons of semi-quantitative structural variables between IIH and aged- and gender-matched reference (REF) subjects showed IIH abnormalities in glial cells, neurons, and capillaries. The present data suggest a key role of disease processes affecting the glia-neuro-vascular interface.

New Options (or not) for Treatment of Idiopathic Intracranial Hypertension

PURPOSE OF REVIEW

Idiopathic intracranial hypertension (IIH) is a disorder primarily affecting obese women of childbearing age and, if left untreated, can lead to irreversible vision loss. No consensus exists on the best management strategy for IIH. Weight loss is advocated and few useful medical options exist. There is an unmet need to discover new treatment options for this increasingly prevalent condition. This article reviews the recent advances and research on the treatment of IIH.

RECENT FINDINGS

Venous sinus stenting (VSS) is now performed in many experienced centers, and there is growing interest in bariatric surgery as a treatment modality. Newly approved anti-obesity drugs are showing effectiveness in weight loss, and novel targeted disease-modifying IIH therapies are being explored. Further evaluation of these novel therapeutic strategies as well as studies exploring the use of anti-obesity drugs in IIH is needed. While VSS is gaining popularity due to its efficacy and low complication rate, there is insufficient evidence to support any surgical procedure over another. Bariatric surgery is appealing for patients with non-sight-threatening IIH and needs to be further explored.

The management of elevated intracranial pressure and sinus vein thrombosis associated with mastoiditis: the experience of eighteen patients

PURPOSE

Cerebral sinus vein thrombosis (CSVT) associated with acute mastoiditis is a rare complication of acute otitis media. Elevated intracranial pressure (ICP) frequently occurs secondary to CSVT. The study aims to review the 5 years of experience of four medical centres to treat sigmoid sinus thrombosis and elevated intracranial pressure in children.

METHODS

Patients with CSVT that developed secondary mastoiditis from 2016 through 2021 were evaluated in four centres from Turkey. Patients diagnosed with a preceding or synchronous mastoiditis and intracranial sinus thrombosis were included in the study. Magnetic resonance imaging (MRI), magnetic resonance venography (MRV), ICP measurements, ophthalmological examinations, thrombophilia studies and treatments for increased ICP have also been recorded.

RESULTS

The study group comprises 18 children. Twelve patients were diagnosed with right-sided, six patients with left-sided sinus vein thrombosis. All of the patients had ipsilateral mastoiditis. The most common presenting symptoms were fever, ear pain, headache, visual disorders and vomiting. The most encountered neurologic findings were papilledema, strabismus and sixth cranial nerve palsy. ICP was over 20 cm H₂O in eleven patients. Anticoagulant treatment, antibiotics, pressure-lowering lumbar puncture and lumboperitoneal shunt were among the treatment modalities.

CONCLUSION

Elevated ICP can damage the brain and optic nerve irreversibly, without treatment. For treating elevation of ICP associated with cerebral sinus thrombosis, pressure-lowering lumbar puncture (LP), acetazolamide therapy, optic nerve sheath fenestration (ONSF) and cerebrospinal fluid (CSF)-shunting procedures are suggested in case of deteriorated vision.

The Pre-Lumbar puncture Intracranial Hypertension Scale (PLIHS): A practical scale to identify subjects with normal cerebrospinal fluid pressure in the management of idiopathic intracranial hypertension

BACKGROUND

Idiopathic Intracranial Hypertension (IIH) diagnosis requires lumbar puncture to measure cerebrospinal fluid (CSF) pressure. The Pre-Lumbar puncture Intracranial Hypertension Scale (PLIHS) is aimed to detect cases that will show raised or normal CSF opening pressure.

METHODS

Retrospective analysis of records of patients who underwent lumbar puncture for suspect IIH. The target was CSF opening pressure ≥ 250 mmH2O, whereas a set of known neurological, neuro-ophthalmological and neuro-radiological parameters, plus obesity, were used as predictors in a logistic regression model. The PLIHS was based on significant predictors and a cut-off was validated using chi-squared test around CSF opening pressure ≥ 250 and < 200 mmH2O.

RESULTS

Records of 162 patients were included: CSF opening pressure was <200 mmH2O in 40 and ≥ 250 mmH2O in 95 patients; 85 fulfilled IIH diagnosis. PLIHS is based on Frisén grade 2 or higher papilledema, tinnitus, empty sella, perioptic subarachnoid space distension, and obesity. Score range is 0-7: correlation with CSF opening pressure is 0.508 (p < .001), and PLIHS score is different between subjects not diagnosed with IIH, and those diagnosed with IIH both with and without papilledema (p < .001). PLIHS score ≤ 2 identifies cerebrospinal fluid pressure < 200 mmH2O; PLIHS score ≥ 3 identifies CSF opening pressure ≥ 250 mmH2O, IIH diagnosis, visual acuity ≤0.7, and optic nerve atrophy.

CONCLUSIONS

The PLIHS, can be used to identify patients who will particularly need LP, thus helping with the organization of the diagnostic work-up by optimising healthcare resources and potentially limit the likelihood to incur in LP-related adverse events.

A 270-Degree Decompression of Optic Nerve in Refractory Idiopathic Intracranial Hypertension Using an Ultrasonic Aspirator - A Prospective Institutional Study

Background

Although the nonsurgical treatment for idiopathic intracranial hypertension (IIH) involves weight loss, diuretics, and steroids, surgical intervention is required if there is a worsening of symptoms or visual deterioration.

Objective

To determine the efficacy and complications of transcranial optic nerve sheath fenestration (ONSF) using an ultrasonic aspirator as an adjunct in the treatment of refractory IIH.

Material and Methods

This prospective study included all patients with medically refractory IIH with visual deterioration from November 2017 to June 2019. Pterional craniotomy was followed by extradural clinoidectomy and optic foramen bony decompression using an ultrasonic aspirator. All the cases were followed up for changes in visual acuity and field and surgical outcomes.

Results

A total of 21 consecutive patients who underwent ONSF in the study period were included for analysis. Improvement in visual acuity was noted in 19/21 (90.47%) patients. Improvement in visual fields was noted in 17/21 (80.95%). Headache improved in 66.67% of patients. Improvement in the fundus picture was noted in 90.47%. Symptoms < 6 months showed better results compared to > 6 months symptom, although statistically nonsignificant (P = 0.2556). A 270-degree optic canal decompression was achieved in all the cases.

Conclusion

Transcranial optic nerve sheath decompression with a bone ultrasonic aspirator is a safe and direct decompression of the optic nerve in malignant/refractory cases of IIH.

Utility of CT venography in monitoring stent patency in idiopathic intracranial hypertension: retrospective single-center study

BACKGROUND

Cerebral venous sinus stenting is an established treatment for patients with idiopathic intracranial hypertension (IIH), refractory to medical management and with stenotic venous sinus on conventional cerebral venography. Currently, there are no clear guidelines on optimal noninvasive imaging modality for routine post-stenting follow-up. We investigated diagnostic yield of CT venography (CTV) for evaluation of stent patency.

METHODS

We reviewed our clinical database of patients with a diagnosis of IIH, who underwent stenting of stenotic transverse or transverse/sigmoid sinus junction. Patients who had follow-up CTVs after more than 30 days were included in the final study group. All CTVs were reviewed by two readers for in-stent thrombosis, extrinsic stent compression, juxta-stent stenosis, and new contralateral venous sinus stenosis. Inter-observer agreement and association of stent patency with clinical outcomes (headache and papilledema) were assessed.

RESULTS

In all 36 included patients with 38 cerebral venograms for stenting, follow-up CTVs demonstrated adequate opacifications of the venous sinuses and stents for confident evaluation for in-stent thrombosis, extrinsic stent compression, juxta-stent stenosis, and new contralateral venous sinus stenosis, with inter-observer agreement coefficient of 0.7, 1.0, 0.8, and 1.0 respectively. Association between abnormal CTV and higher rates of persistent headache and lower rates of headache improvement/resolution was statistically significant (P-value of 0.01).

CONCLUSION

CTV is a reliable noninvasive imaging modality for evaluation of cerebral venous sinuses and stent patency following treatment of idiopathic intracranial hypertension with venous sinus stenting and could be used as a routine follow-up study.

Outcome of idiopathic intracranial hypertension after laparoscopic sleeve gastrectomy

BACKGROUND

Idiopathic intracranial hypertension (IIH) predominantly affects young, obese women and presents with signs and symptoms of increased intracranial pressure, such as headaches and visual impairment.

OBJECTIVE

We aim to present our experience in the management of IIH.

SETTING

University Hospital.

METHODS

Obese IIH patients who had a laparoscopic sleeve gastrectomy during the study period (2 years) were included. Data were retrieved from prospectively collected database. Headaches, visual alterations, and medications or interventions used to treat are discussed.

RESULTS

The study included 16 obese women with IIH. Mean age was 31 ± 2 years (range, 25-44 yr) and mean body mass index was 46 ± 4 kg/m² (range, 42-53 kg/m²). Main symptoms and signs were chronic headaches (14), impaired vision (15), vision loss (1), papilledema (6), and field defects in 4 patients. Symptoms were present for a mean of 5 years (4-11). History of medical treatment with carbonic anhydrase inhibitor (acetazolamide) and thecoperitoneal shunting was present in 12 and 9 patients, respectively. Mean lumbar puncture opening pressure was 41.2 ± 21- (range, 30-64) cm water. At 12 months after laparoscopic sleeve gastrectomy, body mass index and percentage excess weight loss were 27.8 ± 1 kg/m² and 75.2 ± 2%, respectively. Symptoms gradually improved with complete resolution in all but 2 patients (87.5%).

CONCLUSION

The present work emphasizes the role of bariatric surgery in the management of obese patients with IIH. Larger, prospective, controlled studies are needed.

Update on the Diagnosis and Treatment of Idiopathic Intracranial Hypertension

Advances in ophthalmic diagnostics and results of interventional clinical trials are shifting diagnosis and management of idiopathic intracranial hypertension (IIH) to be more technology- and evidence-based. In this article, the evidence supporting current diagnostic criteria, evaluation, and medical and surgical management of IIH are reviewed.

Understanding the complex pathophysiology of idiopathic intracranial hypertension and the evolving role of venous sinus stenting: a comprehensive review of the literature

Idiopathic intracranial hypertension (IIH) is a disease defined by elevated intracranial pressure without established etiology. Although there is now consensus on the definition of the disorder, its complex pathophysiology remains elusive. The most common clinical symptoms of IIH include headache and visual complaints. Many current theories regarding the etiology of IIH focus on increased secretion or decreased absorption of cerebrospinal fluid (CSF) and on cerebral venous outflow obstruction due to venous sinus stenosis. In addition, it has been postulated that obesity plays a role, given its prevalence in this population of patients. Several treatments, including optic nerve sheath fenestration, CSF diversion with ventriculoperitoneal or lumboperitoneal shunts, and more recently venous sinus stenting, have been described for medically refractory IIH. Despite the availability of these treatments, no guidelines or standard management algorithms exist for the treatment of this disorder. In this paper, the authors provide a review of the literature on IIH, its clinical presentation, pathophysiology, and evidence supporting treatment strategies, with a specific focus on the role of venous sinus stenting.

Characteristics of the cerebrospinal fluid pressure waveform and craniospinal compliance in idiopathic intracranial hypertension subjects

BACKGROUND

Idiopathic intracranial hypertension (IIH) is a condition of abnormally high intracranial pressure with an unknown etiology. The objective of this study is to characterize craniospinal compliance and measure the cerebrospinal fluid (CSF) pressure waveform as CSF is passively drained during a diagnostic and therapeutic lumbar puncture (LP) in IIH.

METHODS

Eighteen subjects who met the Modified Dandy Criteria, including papilledema and visual field loss, received an ultrasound guided LP where CSF pressure (CSFP) was recorded at each increment of CSF removal. Joinpoint regression models were used to calculate compliance from CSF pressure and the corresponding volume removed at each increment for each subject. Twelve subjects had their CSFP waveform recorded with an electronic transducer. Body mass index, mean CSFP, and cerebral perfusion pressure (CPP) were also calculated. T-tests were used to compare measurements, and correlations were performed between parameters.

RESULTS

Cerebrospinal fluid pressure, CSFP pulse amplitude (CPA), and CPP were found to be significantly different (p < 0.05) before and after the LP. CSFP and CPA decreased after the LP, while CPP increased. The craniospinal compliance significantly increased (p < 0.05) post-LP. CPA and CSFP were significantly positively correlated.

CONCLUSIONS

Both low craniospinal compliance (at high CSFP) and high craniospinal compliance (at low CSFP) regions were determined. The CSFP waveform morphology in IIH was characterized and CPA was found to be positively correlated to the magnitude of CSFP. Future studies will investigate how craniospinal compliance may correlate to symptoms and/or response to therapy in IIH subjects.

Recommendations for the selection and treatment of patients with idiopathic intracranial hypertension for venous sinus stenting

INTRODUCTION

Although venous sinus stenting (VSS) has emerged as a promising treatment option for patients with idiopathic intracranial hypertension (IIH) and associated venous sinus stenosis, there is considerable ambiguity regarding patient selection criteria, treatment protocols, and management strategies.

METHODS

An extensive literature review was performed to identify all reports of VSS in patients with IIH using PubMed. Recommendations for the selection and treatment of patients with IIH with VSS are outlined as determined based on author opinion from supporting studies. Due to the lack of randomized trials and few published prospective studies, standard grading scales for recommendations and level of evidence are not fully applicable and therefore a revised grading scale has been provided for recommendations.

RESULTS

The literature review identified a total of eight systematic reviews or meta-analyses and 29 published patient series on VSS. Recommendations for patient selection for diagnostic catheter angiography, angiography procedural considerations, stenting procedural considerations, and retreatment are provided based on the literature. Recommendations that were considered strong included: performance of venous sinus manometry to assess candidacy for treatment prior to stenting; administration of antiplatelet agents prior to stenting and for a follow-up period of at least 3-6 months; performance of post-stenting manometry to confirm resolution of pressure gradient; and performance of repeat angiography and manometry on patients with recurrence of symptoms after resolution with stenting to evaluate for recurrent stenosis.

CONCLUSION

VSS for patients with IIH with venous sinus stenosis is now an established and effective treatment option. These recommendations have been provided, based on a summative review of the available published literature, to assist in standardizing care for patients with IIH undergoing VSS.

Update on Idiopathic Intracranial Hypertension

PURPOSE OF REVIEW

This review presents a critical appraisal of current therapeutic strategies for patients with idiopathic intracranial hypertension (IIH). We present the reader with the most recent evidence to support medical and surgical interventions in patients with IIH and provide recommendations about treatment initiation and escalation. We also indicate areas where knowledge gaps exist regarding therapeutic efficacy and superiority of one intervention over another.

RECENT FINDINGS

A double-masked, randomized prospective study of medical management of patients with mild IIH (Idiopathic Intracranial Hypertension Treatment Trial-IIHTT) has established that acetazolamide therapy has additional efficacy when compared to weight loss alone. Furthermore, management of IIH-related headache, even in patients with papilledema, may require treatment other than ICP lowering for patients to experience symptomatic relief. Finally, a number of uncontrolled interventional studies have shown transverse sinus stenting to be a potentially effective treatment for medically refractory IIH. Medical therapy with acetazolamide should be considered in addition to structured weight loss in patients with mild IIH. Surgical treatment for patients with vision-threatening disease IIH can be performed by either optic nerve sheath fenestration or cerebrospinal fluid diversion, with venous sinus stenting emerging as an alternate therapy. Headache relief from ICP lowering therapy is variable and often not sustained.

Update on the application of optic nerve sheath fenestration

BACKGROUND

With the ongoing development of surgical procedures and instruments, the safety of optic nerve sheath fenestration (ONSF) has been improved.

OBJECTIVE

Through the past three decades, progress has been made in preventing visual loss from chronic optic nerve swelling in idiopathic intracranial hypertension (IIH), secondary intracranial hypertension and local optic nerve diseases. We now review the updated application of ONSF in those diseases.

METHODS

The application of ONSF in papilledema due to IIH, secondary intracranial hypertension to cerebral venous sinus occlusion, Cryptococcal meningitis, and intracranial mass or tumors is reviewed. Additionally, the potential benefits of ONSF in local optic neuropathy from optic nerve sheath meningioma, optic nerve drusen, traumatic optic neuropathy and optic nerve/sheath biopsy are also described.

RESULTS

Although ONSF has little or no effect on intracranial pressure, it is a safe, relative easy and effective surgical procedure to prevent or reverse visual loss in IIH. When other treatment modalities fail to timely protect vision, ONSF can be useful in protecting visual function or delay visual loss in secondary intracranial hypertension.

CONCLUSION

We recommend that ONSF should be considered as a meaningful alternative or an adjunct therapy to reduce or delay the visual morbidity of these diseases, although the use of ONSF for some of them remains controversial.

Ultrasound for the assessment of distal shunt malfunction in adults with internal ventricular shunts

Shunts that are used for the treatment of hydrocephalus have a propensity towards malfunction, however, diagnosing a shunt malfunction can sometimes be a challenge. The purpose of this study was to investigate whether ultrasound technology can be safely and effectively used to assess for distal shunt malfunction. This was a prospective cohort study at a single institution. Eighteen adult patients that received a radionuclide shunt patency study also underwent an ultrasound shunt patency study. Ultrasound with Doppler technology was used to visualize flow through the shunt tubing following manual compression of the shunt reservoir. A peak flow speed was recorded and the results were compared to the results of the radionuclide shunt patency study. A Receiver Operating Characteristic (ROC) curve comparing the ultrasound to the radionuclide shunt patency study was generated, revealing an Area Under the Curve (AUC) of 0.95 (95% CI: 0.84-1.00). The ultrasound test performed maximally with a cutoff speed of ≤10cm/s as the criteria for malfunction, with a sensitivity of 100.00%, specificity of 90.91%, accuracy of 94.44%, positive likelihood ratio of 11.000 and negative likelihood ratio of 0.000 using the radionuclide study results as criteria for comparison. Overall, ultrasound has the potential to be a safe, quick, available and cost-effective screening test for patients with suspected distal shunt malfunction. The high sensitivity of the test makes it an attractive option for use as a screening method that could potentially reduce the number of cases requiring radionuclide shunt patency study.

An update on idiopathic intracranial hypertension

BACKGROUND

Idiopathic intracranial hypertension (IIH) is still a grey area in the knowledge of the aetiology, diagnosis and management of neurosurgical diseases. The definition of IIH has been reviewed over time and many hypotheses have been expressed as cause of the disease. The literature supplies very little evidence-based information to guide our decision-making process when it comes to treat the disease. In this review we sum up the latest information regarding the aetiology and therapy of IIH. Additionally, we make an attempt to unify the diagnostic criteria of Dandy, Friedman and Wall established from 1937 to date.

METHOD

In this narrative review, we attempt to update the current standpoint to IIH, evaluate the input until now and consider future directions for research. The vast majority of the literature consisted of cohort studies, case control studies, systematic reviews and other narrative reviews.

RESULTS

Pathophysiology: The incidence of IIH is steadily increasing. Several pathophysiological theories have been proposed in the literature based on the flow of cerebrospinal fluid.

DIAGNOSIS

We attempt to fuse all the three diagnostic approaches published in the literature that detect IIH, while preserving the individual characteristics of each approach.

TREATMENT

Based on evidence-based trials, the current use of acetazolamide in comparison with placebo or with topiramate has been evaluated. In the interventions' field, there seems to be a consonance about the alarming symptoms and what the most suitable operation is in each case. There is some disagreement about the indications for venous sinus transversus stenting and its risk/benefit ratio.

CONCLUSIONS

Until now there is no class I guideline to which our decision-making can be based on for the management of IIH. A lack of systematic reviews and randomised control trials has been noted. If we focused our research on that, we could develop a standardised treatment protocol.

Dural venous sinus stenting for medically and surgically refractory idiopathic intracranial hypertension

Background Idiopathic intracranial hypertension (IIH) is a syndrome defined by elevated intracranial hypertension without radiographic evidence of a mass lesion in the brain. Dural venous sinus stenosis has been increasingly recognized as a treatable cause, and dural venous sinus stenting (DVSS) is increasingly performed. Methods A 5 year single-center retrospective analysis of consecutive patients undergoing DVSS for medically refractory IIH. Results There were 43 patients with a mean imaging follow-up of 6.5 months and a mean clinical follow-up period of 13.5 months. DVSS was performed as the first procedure for medically refractory IIH in 81.4% of patients, whereas 18.6% of patients included had previously had a surgical procedure (ventriculoperitoneal (VP) shunt or optic nerve sheath fenestration (ONSF)). Headache was present in all patients and after DVSS improved or remained stable in 69.2% and 30.8%, respectively. Visual acuity changes and visual field changes were present in 88.4% and 37.2% of patients, respectively. Visual field improved or remained unchanged in 92%, but worsened in 8% after stenting. There was a stent patency rate of 81.8%, with an 18.2% re-stenosis rate. Of the 43 procedures performed, there was a 100% technical success rate with zero major or minor complications. Conclusion Based on this single-center retrospective analysis, DVSS can be performed with high technical success and low complication rates. A majority of patients presented primarily with headache, and these patients had excellent symptom relief with DVSS alone. Patients presenting with visual symptoms had lower success rates, and this population, if stented, should be carefully followed for progression of symptoms.

Efficacy, complications and cost of surgical interventions for idiopathic intracranial hypertension: a systematic review of the literature

BACKGROUND

To define the efficacy, complication profile and cost of surgical options for treating idiopathic intracranial hypertension (IIH) with respect to the following endpoints: vision and headache improvement, normal CSF pressure restoration, papilloedema resolution, relapse rate, operative complications, cost of intervention and quality of life.

METHODS

A systematic review of the surgical treatment of IIH was carried out. Cochrane Library, MEDLINE and EMBASE databases were systematically searched from 1985 to 2014 to identify all relevant manuscripts written in English. Additional studies were identified by searching the references of retrieved papers and relative narrative reviews.

RESULTS

Forty-one (41) studies were included (36 case series and 5 case reports), totalling 728 patients. Three hundred forty-one patients were treated with optic nerve sheath fenestration (ONSF), 128 patients with lumboperitoneal shunting (LPS), 72 patients with ventriculoperitoneal shunting (VPS), 155 patients with venous sinus stenting and 32 patients with bariatric surgery. ONSF showed considerable efficacy in vision improvement, while CSF shunting had a superior headache response. Venous sinus stenting demonstrated satisfactory results in both vision and headache improvement along with the best complication profile and low relapse rate, but longer follow-up periods are needed. The complication rate of bariatric surgery was high when compared to other interventions and visual outcomes have not been reported adequately. ONSF had the lowest cost.

CONCLUSIONS

No surgical modality proved to be clearly superior to any other in IIH management. However, in certain contexts, a given approach appears more justified. Therefore, a treatment algorithm has been formulated, based on the extracted evidence of this review. The traditional treatment paradigm may need to be re-examined with sinus stenting as a first-line treatment modality.

Pseudotumor cerebri: an update on treatment options

Aims:

The aim was to identify Pseudotumor cerebri treatment options and assess their efficacy.

Setting and Design:

Review article.

Materials and Methods:

Existing literature and the authors’ experience were reviewed.

Results:

Treatment options range from observation to surgical intervention. Weight loss and medical treatment may be utilized in cases without vision loss or in combination with surgical treatment. Cerebrospinal fluid shunting procedures and/or optic nerve sheath decompression is indicated for severe vision loss or headache unresponsive to medical management. The recent use of endovascular stenting of transverse sinus stenoses has also demonstrated benefit in patients with pseudotumor cerebri.

Conclusion:

While each treatment form may be successful individually, a multimodal approach is typically utilized with treatments selected on a case-by-case basis.

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.

Cortical astrogliosis and increased perivascular aquaporin-4 in idiopathic intracranial hypertension

The syndrome idiopathic intracranial hypertension (IIH) includes symptoms and signs of raised intracranial pressure (ICP) and impaired vision, usually in overweight persons. The pathogenesis is unknown. In the present prospective observational study, we characterized the histopathological changes in biopsies from the frontal brain cortical parenchyma obtained from 18 IIH patients. Reference specimens were sampled from 13 patients who underwent brain surgery for epilepsy, tumors or acute vascular diseases. Overnight ICP monitoring revealed abnormal intracranial pressure wave amplitudes in 14/18 IIH patients, who underwent shunt surgery and all responded favorably. A remarkable histopathological observation in IIH patients was patchy astrogliosis defined as clusters of hypertrophic astrocytes enclosing a nest of nerve cells. Distinct astrocyte domains (i.e. no overlap between astrocyte processes) were lacking in most IIH biopsy specimens, in contrast to their prevalence in reference specimens. Evidence of astrogliosis in IIH was accompanied with significantly increased aquaporin-4 (AQP4) immunoreactivity over perivascular astrocytic endfeet, compared to the reference specimens, measured with densitometry. Scattered CD68 immunoreactive cells (activated microglia and macrophages) were recognized, indicative of some inflammation. No apoptotic cells were demonstrable. We conclude that the patchy astrogliosis is a major finding in patients with IIH. We propose that the astrogliosis impairs intracranial pressure-volume reserve capacity, i.e. intracranial compliance, and contributes to the IIH by restricting the outflow of fluid from the cranium. The increased perivascular AQP4 in IIH may represent a compensatory mechanism to enhance brain fluid drainage.

A comparison of lumboperitoneal and ventriculoperitoneal shunting for idiopathic intracranial hypertension: an analysis of economic impact and complications using the Nationwide Inpatient Sample

OBJECT

Complications following lumboperitoneal (LP) shunting have been reported in 18% to 85% of cases. The need for multiple revision surgeries, development of iatrogenic Chiari malformation, and frequent wound complications have prompted many to abandon this procedure altogether for the treatment of idiopathic benign intracranial hypertension (pseudotumor cerebri), in favor of ventriculoperitoneal (VP) shunting. A direct comparison of the complication rates and health care charges between first-choice LP versus VP shunting is presented.

METHODS

The Nationwide Inpatient Sample database was queried for all patients with the diagnosis of benign intracranial hypertension (International Classification of Diseases, Ninth Revision, code 348.2) from 2005 to 2009. These data were stratified by operative intervention, with demographic and hospitalization charge data generated for each.

RESULTS

A weighted sample of 4480 patients was identified as having the diagnosis of idiopathic intracranial hypertension (IIH), with 2505 undergoing first-time VP shunt placement and 1754 undergoing initial LP shunt placement. Revision surgery occurred in 3.9% of admissions (n = 98) for VP shunts and in 7.0% of admissions (n = 123) for LP shunts (p < 0.0001). Ventriculoperitoneal shunts were placed at teaching institutions in 83.8% of cases, compared with only 77.3% of first-time LP shunts (p < 0.0001). Mean hospital length of stay (LOS) significantly differed between primary VP (3 days) and primary LP shunt procedures (4 days, p < 0.0001). The summed charges for the revisions of 92 VP shunts ($3,453,956) and those of the 6 VP shunt removals ($272,484) totaled $3,726,352 over 5 years for the study population. The summed charges for revision of 70 LP shunts ($2,229,430) and those of the 53 LP shunt removals ($3,125,569) totaled $5,408,679 over 5 years for the study population.

CONCLUSIONS

The presented results appear to call into question the selection of LP shunt placement as primary treatment for IIH, as this procedure is associated with a significantly greater likelihood of need for shunt revision, increased LOS, and greater overall charges to the health care system.

Endoscopic endonasal optic nerve decompression in a patient with pseudotumor cerebri

Pseudotumor cerebri (idiopathic intracranial hypertension) is a syndrome characterized by intracranial pressure elevation and associated signs and symptoms in the absence of a space-occupying intracranial lesion. The most common symptoms are visual loss and headache. Sometimes, surgical therapy is needed in patients who have no apparent response to medical therapy and exhibit a progressive course. Optic nerve decompression is an effective and recommended treatment approach for patients with pseudotumor cerebri in whom visual loss predominates. With the growing experience with endoscopic skull base approaches, this method has begun to be used as an alternative and effective treatment modality. In this study, we aimed to present the outcome of endoscopic endonasal optic nerve decompression and to review the literature on this treatment modality in 2 patients diagnosed with pseudotumor cerebri that was unresponsive to medical therapy and associated with progressive visual loss.

[Treatment of idiopathic intracranial hypertension by endovascular improvement of venous drainage of the brain]

Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is a syndrome of elevated intracranial pressure (ICP) in the absence of any known causative factor. Most patients with IIH respond to weight reduction, repeated lumbar punctures and carbonic anhydrase inhibitors, such as acetazolamide and topiramate to reduce cerebrospinal fluid (CSF) production. Despite a number of pathogenetic theories, the cause of IIH remains unknown. With the availability of magnetic resonance (MR) venography and cerebral angiography, venous disease is increasingly being discussed as the etiology of IIH, with a high proportion of patients presenting with nonthrombotic unilateral or bilateral dural venous sinus stenoses. Based on this observation, endovascular stenting of stenotic dural sinuses in patients with IIH has gained popularity. Whether dural venous sinus stenoses are the cause or the consequence of increased ICP is still under debate. In patients with failure of conservative treatment or non-compliance, a more aggressive treatment, such as CSF shunting or surgical optic nerve fenestration, should be performed. For approximately 13 years endovascular stenting of the stenotic sinuses has been used and discussed as an alternative and effective treatment of IIH. Since the first report in 2002, individual cases and case series have been published demonstrating that stents immediately lower the venous pressure gradient, which is associated with clinical improvement. This effect occurs within days or weeks and is permanent in many cases.

Papilledema: epidemiology, etiology, and clinical management

Papilledema is optic disc swelling due to high intracranial pressure. Possible conditions causing high intracranial pressure and papilledema include intracerebral mass lesions, cerebral hemorrhage, head trauma, meningitis, hydrocephalus, spinal cord lesions, impairment of cerebral sinus drainage, anomalies of the cranium, and idiopathic intracranial hypertension (IIH). Irrespective of the cause, visual loss is the feared morbidity of papilledema, and the main mechanism of optic nerve damage is intraneuronal ischemia secondary to axoplasmic flow stasis. Treatment is directed at correcting the underlying cause. In cases where there is no other identifiable cause for intracranial hypertension (ie, IIH) the available options include both medical and surgical modalities. Weight loss and diuretics remain the mainstays for treatment of IIH, and surgery is typically reserved for patients who fail, are intolerant to, or non-compliant with maximum medical therapy.

Management of idiopathic intracranial hypertension with a programmable lumboperitoneal shunt: Early experience

OBJECTIVE

To evaluate the clinical outcomes and complications rate among idiopathic intracranial hypertension (IIH) patients who underwent lumboperitoneal (LP) shunt insertion with a programmable Strata valve.

METHODS

We retrospectively evaluated patients who underwent LP shunt with a programmable Strata valve insertion at the University of Ottawa Civic Hospital from November 2012 to June 2013. The demographic data, clinical symptoms, opening pressure, pre-operative and post-operative visual fields, neuroimaging, visual acuity, disc status, and complications were recorded and analyzed.

RESULTS

Seven female patients with IIH underwent insertion of an LP shunt with a programmable Strata valve. The mean opening pressure was 35.8 cm H2O. The initial valve setting was 1.5, and four patients required post-operative valve pressure adjustment. All patients showed significant improvement in objective visual testing at follow-up as well as less frequent headaches. None of the patients developed intra- or post-operative complications.

CONCLUSION

LP shunts with programmable Strata valve systems are a potential alternative to conventional LP and programmable ventriculoperitoneal shunt systems as well as optic nerve sheath fenestration, due to their potential in avoiding brain injury, lower failure and complication rates, lower intracranial hypotension incidence, and flexibility in adjusting valve pressure settings post-operatively evading under- and overdrainage complications. They should be considered for the management of IIH instead of early design LP systems and VP shunts. A randomized multi-center trial should be conducted to compare the efficacy of these surgical techniques.

Ventriculoperitoneal shunt as a treatment of visual loss in idiopathic intracranial hypertension

BACKGROUND

The aims of this study were to evaluate visual function outcomes in idiopathic intracranial hypertension (IIH) patients who underwent ventriculoperitoneal (VP) shunt for visual loss and to determine a VP shunt survival curve over time.

METHODS

A retrospective medical record review was performed of all new IIH patients first evaluated at our institution who underwent VP shunt placement over a 7-year period (2004-2010). There were 2 primary outcome measures: the first being visual acuity (VA) and the second being shunt survival. Patients who received VP shunt for visual loss were included in the visual outcome analysis, and all patients who received VP shunt for any reason were included in the shunt survival analysis.

RESULTS

Of the 338 new patients with IIH, 19 patients (6%) met the inclusion criteria and 17 underwent VP shunt for visual loss and 2 for headaches. Average follow-up was 21.2 months (range, 5-1,342 days). Of the 17 patients who had VP shunt for visual loss, 5 patients had optic nerve sheath fenestration (ONSF) surgery before VP shunt, and 1 patient had bilateral ONSF surgery after VP shunt. Median VA before shunt was 20/200 in the worse eye (range, 20/20 to NLP) and 20/40 in the better eye (20/20 to HM). Median VA after shunt was 20/60 in the worse eye (20/20 to lumboperitoneal) and 20/30 in the better eye (20/20 to 20/800). The improvement in VA was statistically significant in both worse eyes (P = 0.002, Wilcoxon signed-rank test) and better eyes (P = 0.028). The mean automated visual field (AVF) mean deviation (MD) of available AVFs before shunt was 223.36 dB (range, 233.38 to 27.01 dB) for the worse eye (n = 11) and 219.66 dB (230.11 to 25.91 dB) for the better eye (n = 11). Mean AVF MD deviation of available AVFs after shunt was 220.68 dB (232.13 to 23.97 dB) for the worse eye (n = 11) and 216.35 dB (232.13 to 21.00 dB) for the better eye (n = 11): this improvement was not significant (P = 0.27, P = 0.26, respectively). Independent masked record reviews by 3 neuro-ophthalmologists showed that 9 (53%) patients improved, 5 (29%) unchanged, 1 (6%) worsened, and 2 (12%) were indeterminate. Kaplan-Meier analysis showed a persistent steady decrease of functioning VP shunts over the entire period of 36 months with 80%, 65%, and 48% of VP shunts functioning without replacement, removal, or revision at 12, 24, and 36 months, respectively.

CONCLUSION

VP shunts improve or stabilize most IIH patients presenting with severe progressive visual loss or those with visual loss refractive to medical treatment and ONSF. Survival analysis shows persistent decrease of functioning shunts over time.

Visual Outcomes from Shunting for Idiopathic Intracranial Hypertension

A retrospective notes review was conducted for 50 consecutive patients who underwent shunt surgery for idiopathic intracranial hypertension (IIH). The decimal visual acuity and the mean radial degrees (MRD) of the I4e isopter of the Goldmann visual field were measured pre-operatively and after a mean follow-up period of 1123 days (range: 13-3551 days). A ventriculo-peritoneal shunt was the first procedure in 38 patients and a lumbo-peritoneal shunt in 12. The mean decimal visual acuity of the worse affected eye improved from 0.75 to 0.84, p = 0.011. The MRD score of the worse affected eye improved on average from 25.6° to 35.5°, p < 0.0001. In those with significant pre-operative visual impairment in their worse affected eye (defined as an MRD score ≤30°), the MRD score improved on average from 10.3° to 26.5°, p = 0.0008. The mean number of surgical procedures for each patient was 2.8 (range: 1-15). Taking all surgical procedures into account, post-operative complications were experienced by 30 patients. At last follow-up, 28 patients still complained of headache, 8 of whom had the intervention performed primarily for headache. Shunting can improve visual function in patients with IIH. There is significant post-operative morbidity and often the need for repeated procedures. Headache also commonly remains in these patients. There is a need for a randomised controlled trial of operative interventions in IIH. Sample size calculations for such a trial to treat significant vision loss are presented.

Papilledema and idiopathic intracranial hypertension

PURPOSE OF REVIEW

Papilledema is one of the most concerning physical examination findings in neurology: it has a broad differential diagnosis of intracranial (and occasionally spinal) pathology associated with increased intracranial pressure. Papilledema impairs axoplasmic flow within the optic nerves and compresses the optic nerves externally; it may lead to profound visual loss. Thus, detection of papilledema and assessment of visual function are essential to patient management. This article reviews the treatment of papilledema-related visual loss in pseudotumor cerebri syndrome, one of the most common causes of papilledema encountered by neurologists.

RECENT FINDINGS

Results from the Idiopathic Intracranial Hypertension Trial (IIHTT), the first randomized, double-masked, placebo-controlled trial for the treatment of patients with mild visual loss from idiopathic intracranial hypertension, were published in April 2014. The IIHTT provides the first evidence-based treatment recommendations, showing the benefit of acetazolamide and weight loss for improving visual status in patients with mild visual field loss from idiopathic intracranial hypertension.

SUMMARY

A detailed ophthalmic examination, including perimetry, is critical to the evaluation, treatment, and assessment of treatment response in patients with papilledema.

Unilateral endoscopic optic nerve decompression for idiopathic intracranial hypertension: a series of 10 patients

OBJECTIVE

Several surgical treatment modalities, including lumboperitoneal or ventriculoperitoneal shunt surgery, subtemporal decompression, endovascular venous sinus stenting, optic nerve decompression (OND), were used in the management of idiopathic intracranial hypertension (IIH). Each surgical technique has different advantages and disadvantages. Endoscopic OND is rarely used in the management of IIH. There are only four reported cases. The aim of this study is to describe the surgical results of patients treated with this less invasive surgical technique.

METHODS

A series of 10 consecutive cases of unilateral OND was reviewed. Between December 2008 and December 2012 these patients underwent the endoscopic approach without nerve sheath opening. Presenting symptoms, neurological examination findings, magnetic resonance venography imaging results, fundoscopic and visual acuity examination findings, and automated perimetry test results were recorded. Perioperative results, including complications and length of hospital stay, were evaluated. Findings at follow-up evaluations were also recorded.

RESULTS

This report is the first series of unilateral OND performed using the endoscopic approach. The mean patient age was 34.1 years (range, 9-49 years); there were nine female and one male patients. Visual impairment was the main symptom in this patient group, whereas headache was a secondary complaint. The patients were first managed with medical treatment for at least 3 months. Unilateral endoscopic OND was performed on the side with the most visual failure. Mean follow-up was 28.4 months (range, 8-55 months). The visual field defects and visual acuity improved in eight of nine patients, whereas papilloedema improved in seven of nine patients. Also headaches resolved in four of seven patients. There were no complications in this relatively small series.

CONCLUSIONS

The surgical treatment of IIH by using the unilateral endoscopic OND technique is a safe and effective method in the hands of experienced surgeons with advanced endoscopic skills. A collaboration with the ophthalmology team is needed for the follow-up. Further studies with larger patient numbers is needed to compare unilateral endoscopic OND technique with the current techniques used in the surgical management of IIH.