Idiopathic intracranial hypertension: Contemporary review and implications for the otolaryngologist

Deep learning to predict risk of lateral skull base cerebrospinal fluid leak or encephalocele

PURPOSE

Skull base features, including increased foramen ovale (FO) cross-sectional area, are associated with lateral skull base spontaneous cerebrospinal fluid (sCSF) leak and encephalocele. Manual measurement requires skill in interpreting imaging studies and is time consuming. The goal of this study was to develop a fully automated deep learning method for FO segmentation and to determine the predictive value in identifying patients with sCSF leak or encephalocele.

METHODS

A retrospective cohort study at a tertiary care academic hospital of 34 adults with lateral skull base sCSF leak or encephalocele were compared with 815 control patients from 2013-2021. A convolutional neural network (CNN) was constructed for image segmentation of axial computed tomography (CT) studies. Predicted FO segmentations were compared to manual segmentations, and receiver operating characteristic (ROC) curves were constructed.

RESULTS

295 CTs were used for training and validation of the CNN. A separate dataset of 554 control CTs was matched 5:1 on age and sex with the sCSF leak/encephalocele group. The mean Dice score was 0.81. The sCSF leak/encephalocele group had greater mean (SD) FO cross-sectional area compared to the control group, 29.0 (7.7) mm2 versus 24.3 (7.6) mm2 (P = .002, 95% confidence interval 0.02-0.08). The area under the ROC curve was 0.69.

CONCLUSION

CNNs can be used to segment the cross-sectional area of the FO accurately and efficiently. Used together with other predictors, this method could be used as part of a clinical tool to predict the risk of sCSF leak or encephalocele.

Frontonasal Encephalocele Complicated With Pseudotumor Cerebri: A Case Report and Literature Review

Primary pseudotumor cerebri syndrome (PPTS) is a rare disorder of elevated intracranial pressure (ICP) in the absence of an identifiable underlying etiology. Afflicted patients are usually obese women in their reproductive age presenting with symptoms of elevated ICP. Seldom, patients can present with an encephalocele. We reported a case of a 31-year-old female who initially presented to our center with complaints of headaches, foreign body sensation in the nasal cavity, and decreased ability to smell. Brain computed tomography (CT) scan showed a large intranasal encephalocele and defect along the frontal skull base, through which brain tissue was herniating. The patient was successfully treated surgically by implantation of a lumboperitoneal shunt to manage the high ICP caused by her PPTS. In combination, reconstruction of the frontal skull base defect for the encephalocele was performed. Currently, the patient is doing well despite some on-and-off headaches.

Dural sinus narrowing in patients with spontaneous anterior skull base cerebrospinal fluid leak

Objectives

Current evidence suggests a link between idiopathic intracranial hypertension (IIH) and spontaneous cerebrospinal fluid (sCSF) leak, as well as between IIH and dural venous sinus (DVS) narrowing. However, there are limited data linking DVS narrowing and sCSF leak. This study aims to determine the prevalence of DVS narrowing in patients with sCSF leak.

Methods

A retrospective review of all patients with sCSF leak that presented to a tertiary academic center from 2008 to 2019. Preoperative imaging was independently reviewed by two neuroradiologists to evaluate for DVS narrowing. Available literature was used to estimate the prevalence of DVS narrowing in the general population to allow for comparison. Data were analyzed using Exact binomial test.

Results

Analysis of 25 patients with appropriate imaging revealed the majority were women (21/25, 84%) with a mean age of 51.89 years (SD 13.96). The majority of these patients were found to have narrowing of the DVS (20/25, 80%). In patient with sCSF leaks, there was a significantly higher proportion of patients with DVS narrowing compared with published literature examining this condition in the general population (80% vs. 40%, CI 0.59-0.93, p < .001).

Conclusion

The prevalence of DVS narrowing in patients with sCSF leaks is substantial and likely greater than the general population. Moreover, there appears to be narrowing in most patients with sCSF leak. Preoperative radiological evaluation of the DVS using MR venography may be useful in patients with sCSF leaks as DVS stenosis may be an underdiagnosed etiology. Further study is needed to evaluate this.

Level of Evidence

IV.

Management of recurrent cerebrospinal fluid leak, current practices and open challenges. A systematic literature review

Cerebrospinal fluid leak (CSFL) is a rare pathological condition which requires prompt and adequate management due to the high rate of associated major complications. At present, CSFL can be successfully treated through endoscopic endonasal approaches with success rates higher than 90%. Despite this, CSFL recurrence may occur, and its management is critical and still represents a matter of debate. A systematic review of the literature on the management of recurrent CSFL was conducted. It included a cohort of 1,083 cases of CSFL treated with surgical or conservative approaches; 112 cases of recurrence were reported for an overall recurrence rate of 10.3%. Most of the leaks were localised in the anterior skull base (68.3%) and identification of recurrent CSFL may be troublesome. Therefore, the entire skull base must be meticulously examined and long-term follow-up is mandatory. The risk for CSFL recurrence is higher in patients affected by idiopathic intracranial hypertension (IIH), but its role in CSFL recurrence is yet to be understood. Recurrent CSFL must be repaired as soon as possible in order to reduce the risk of intracranial complications. The use of early post-operative CSF diversion by lumbar drain (LD) is currently a matter of debate even in case of CSFL recurrences.

Cerebrospinal Fluid Shunting for Idiopathic Intracranial Hypertension: A Systematic Review, Meta-Analysis, and Implications for a Modern Management Protocol

BACKGROUND

Cerebrospinal fluid (CSF) shunting is widely used in refractory idiopathic intracranial hypotension (IIH). Although multiple reviews have assessed its efficacy compared with other surgical treatments, there is no detailed analysis that evaluates the clinical outcomes after CSF shunting.

OBJECTIVE

To conduct a meta-analysis of the clinical impact of CSF shunting for refractory IIH and use this in conjunction with existing information on other treatment modalities to develop a modern management protocol.

METHODS

PubMed and Embase were systematically searched for studies describing CSF shunting for medically refractory IIH. Relevant information including study characteristics, patient demographics, clinical outcomes, periprocedural complications, and long-term outcomes were subjected to meta-analysis.

RESULTS

Fifteen studies published between 1988 and 2019 met our inclusion and exclusion criteria, providing 372 patients for analysis. The mean age was 31.2 years (range 0.5-71) with 83.6% being female. The average follow-up was 33.9 months (range 0-278 months). The overall rate of improvement in headache, papilledema, and visual impairment was 91% (95% CI 84%-97%), 96% (95% CI 85%-100%), and 85% (95% CI 72%-95%), respectively. Of 372 patients, 155 had 436 revisions; the overall revision rate was 42% (95% CI 26%-59%). There was no significant correlation between average follow-up duration and revision rates in studies ( P = .627). Periprocedural low-pressure headaches were noted in 74 patients (20%; 95% CI 11%-32%).

CONCLUSION

CSF shunting for IIH is associated with significant improvement in clinical symptoms. Shunting rarely causes periprocedural complications except overdrainage-related low-pressure headache. However, CSF shunting has a relatively high revision rate.

Optic Disc Edema and Elevated Intracranial Pressure (ICP): A Comprehensive Review of Papilledema

Papilledema is a swelling of the optic disc secondary to elevated intracranial pressure (ICP). We analyzed 79 peer-review journal articles and provided a concise summary of the etiology, epidemiology, pathophysiology, clinical presentation, evaluation, natural history, differential diagnosis, treatment, and prognosis of papilledema. Only studies written in English with the full text available were included. Although many etiologies of papilledema exist, idiopathic intracranial hypertension is the most common and, thus, a large focus of this review.

Idiopathic Intracranial Hypertension: Implications for the Otolaryngologist

Idiopathic intracranial hypertension (IIH) is a triad of headaches, visual changes, and papilledema in the absence of a secondary cause for elevated intracranial pressure. There is an association with obesity, and the incidence is rising in parallel with the obesity epidemic. Sometimes these patients present to an otolaryngologist with complaints like tinnitus, dizziness, hearing loss, and otorrhea or rhinorrhea from cerebrospinal fluid leak. IIH diagnosis in conjunction with neurology and ophthalmology, including neuroimaging and lumbar puncture with opening pressure, is key to managing of this condition. Otolaryngologists should recognize IIH as a possible diagnosis and initiate appropriate referrals and treatment.

Exploring Vestibular Assessment in Patients with Headache and Dizziness

Patients often report symptoms of headache and dizziness concomitantly. Symptoms of dizziness can be explored with a comprehensive vestibular assessment, allowing for the investigation of central and peripheral vestibular system contributions to symptoms of dizziness. Patients who report both symptoms of headache and dizziness demonstrate abnormalities of the vestibular system which can be measured quantitatively. Completion of comprehensive vestibular testing can help to guide diagnosis and strategies for intervention.

Postoperative Radiologic Assessment and Long-Term Clinical Results of Tegmen Mastoideum Defects

Objective

Tegmen defects occur mainly due to cholesteatoma and iatrogenic trauma, and the intervention for the related defects is still a debate. In this study, we aimed to discuss our clinical experience on the management of the tegmen defects which were revealed during the mastoidectomy surgeries.

Methods

This study was designed as a retrospective chart review study and patients who were operated between 2007-2017 were included. The causes of the defects, repair technics, and results of the long-term follow up were evaluated. The perioperative and postoperative defect sizes which were obtained from the radiological studies were analyzed.

Results

Total number of 62 patients had tegmen defects, and their etiologic factors were cholesteatoma in 31 (50%), iatrogenic factors in 29 (46.7%), and chronic infection in 2 (3.3%) patients. The number of the tegmen defects was higher in intact canal wall technic. All of the tegmen defects were repaired with different materials, and no complication was detected. The obtained data from the postoperative radiological images revealed that the related perioperative defects were significantly decreased (p<0.001).

Conclusion

The perioperative bone defects were observedly decreased significantly in postoperative period. Early detection of the defect and appropriate interventions may help to manage this problem without any complication in the long term.

An Exploration of Online Support Community Participation Among Patients With Vestibular Disorders

OBJECTIVES/HYPOTHESIS

To formally document online support community (OSC) use among patients with vestibular symptoms and gain an appreciation for the perceived influence of participation on psychosocial outcomes and the impact on medical decision-making.

STUDY DESIGN

Self reported internet-based questionnaire.

METHODS

The Facebook search function was paired with a comprehensive list of vestibular diagnoses to systematically collect publicly available information on vestibular OSCs. Next, a survey was designed to gather clinicodemographic information, OSC characteristics, participation measures, perceived outcomes, and influence on medical decision-making. The anonymous instrument was posted to two OSCs that provide support for patients with general vestibular symptoms.

RESULTS

Seventy-three OSCs were identified with >250,000 cumulative members and >10,000 posts per month. The survey was completed by 549 participants, a cohort of primarily educated middle-aged (median = 50, interquartile range 40-60), non-Hispanic white (84%), and female (89%) participants. The participants' most cited initial motivation and achieved goal of participants was to hear from others with the same diagnosis (89% and 88%, respectively). Daily users and those who reported seeing ≥5 providers before receiving a diagnosis indicated that OSC utilization significantly influenced their requested medical treatments (72% daily vs. 61% nondaily, P = .012; 61% <5 providers vs. 71% ≥5 providers P = .019, respectively). Most participants agreed that OSC engagement provides emotional support (74%) and helps to develop coping strategies (68%). Membership of ≥1 year was associated with a higher rate of learned coping skills (61% membership <1-year vs. 71% ≥1-year P = .016).

CONCLUSIONS

The use of OSCs is widespread among vestibular diagnoses. A survey of two OSCs suggests these groups provide a significant source of peer support and can influence users' ability to interface with the medical system.

LEVEL OF EVIDENCE

N/A Laryngoscope, 2021.

Large Primary Transethmoidal Encephalocele Presenting in an Adult

Transethmoidal encephaloceles are rare and most commonly present at birth with congenital abnormalities, cerebrospinal fluid rhinorrhea, or visual symptoms. Here, we report the case of a 43-year-old presenting with longstanding headache, blurry vision, anosmia, and rhinorrhea. Magnetic resonance imaging confirmed a transethmoidal encephalocele. The patient underwent craniotomy for resection of the encephalocele and repair of the cribriform defect. The postoperative course was uneventful, and the patient was discharged home with the resolution of rhinorrhea and headache. This report highlights a rare case of primary transethmoidal encephalocele undiagnosed until adulthood despite longstanding symptoms and successful treatment with resolution of symptoms.

Imaging Characteristics of Sigmoid Sinus Wall Anomalies, Idiopathic Intracranial Hypertension, and Spontaneous CSF Leaks

OBJECTIVE

To assess the frequency of radiographic features of elevated intracranial pressure (ICP) in patients with sigmoid sinus wall anomalies (SSWA) and compare to those in idiopathic intracranial hypertension (IIH) and spontaneous CSF (sCSF) leaks.

STUDY DESIGN

Retrospective review.

SETTING

Tertiary care center.

PATIENTS

110 patients - 62 SSWAs, 19 IIH, 29 sCSF leaks.

MAIN OUTCOME MEASURES

Demographics, comorbidities and radiographic features by diagnosis.

RESULTS

Imaging findings indicative of elevated ICP were similar across all three groups, as were body mass index, hyperlipidemia and diabetes. On univariate analysis, sCSF leak patients were significantly older than SSWA (60 vs. 41 years, p < 0.001) and IIH (60 vs. 40 years, p < 0.001) patients. They had a greater prevalence of arachnoid granulations than SSWA (75.8% vs. 37.1%, p < 0.01) and tegmen dehiscence than both SSWA and IIH (93.1% vs. 75.8% vs. 57.8%, p = 0.01), though a lower prevalence of empty sella than SSWA (44.8% vs. 72.5%, p < 0.001). SSWAs were present in roughly 44.3% of IIH and sCSF leak patients, and IIH in roughly 15.8% of SSWA and sCSF leak patients. Age (OR = 1.1, p = 0.001), hypertension (OR = 8.3, p = 0.01) and empty sella (OR = 0.1, p = 0.01) were predictive of sCSF leaks compared to SSWAs on multivariate analysis.

CONCLUSIONS

Many radiographic and clinical features of elevated ICP are found at similar rates among patients with SSWA, IIH and sCSF leaks, suggesting a common underlying process. SSWAs seem to present earlier along this spectrum of phenotypes, while sCSF leaks present later. Differences in age, metabolic syndrome and ICP may influence a patient's clinical presentation.

Spontaneous cerebrospinal fluid leaks of the temporal bone - clinical features and management outcomes

OBJECTIVE

METHODS: A retrospective cohort study over seven-years from 2013 to 2020 was conducted at five tertiary referral centres. Patients identified with biochemically confirmed spontaneous cerebrospinal fluid leaks of the temporal bone manifesting as middle ear fluid with no other obvious cause were included. Demographics (age, gender, body-mass-index), symptomatology, past medical history, examination, investigation (biochemical and radiological), management and outcomes were recorded.

RESULTS

90 adult patients with spontaneous cerebrospinal fluid otorrhoea were identified. Right sided leaks were most common (58%), and a majority of the cohort overweight (mean body-mass-index = 29.2 kg/m²). Unilateral hearing loss was the commonest presenting symptom (81%). Two patients presented to hospital with meningitis presumed secondary to spontaneous cerebrospinal fluid otorrhoea. Over half (54%) of patients were observed who tended to be older (mean age of 71 years vs 62 years) whilst the remainder underwent surgical repair with middle-fossa craniotomy the most common approach (87%). Eight patients managed surgically had recurrent leaks (21%).

CONCLUSIONS

This is one of the largest cohorts of spontaneous cerebrospinal fluid otorrhoea reported in the literature and reiterates the importance for clinicians to have a high index of suspicion for this condition in patients presenting with a unilateral middle ear effusion, especially in those who are overweight. Surgical intervention carries a risk of recurrence and further studies are needed to determine the risk of intra-cranial infection in order to guide management.

Etiology, pathogenesis and management of idiopathic intracranial hypertension, and role of optic canal size in asymmetric papilledema: A review

Idiopathic intracranial hypertension (IIH) is characterized by raised intracranial pressure of unknown origin that primarily afflicts obese women of childbearing age. There are several treatment options, but currently there are none that are effective for the entire affected population. The lack of a universally effective treatment is related to an incomplete understanding of the etiology of the condition and the lack of a well-defined pathophysiological mechanism for the disease process. Classically, IIH has been thought of as a diagnosis of exclusion once radiographical imaging has ruled out all other causes of elevated intracranial pressure. Today, we know that imaging does capture subtle changes, and might provide keys to finally understand the pathogenesis of IIH so that a definitive treatment can be discovered or developed. Recently, advancements in radiography, optical coherence tomography, and electroretinography have shown promise for the future of IIH evaluation. A topic within IIH imaging that has recently sparked interest is the possibility that the severity of papilledema may have an association with the size of the optic canal. In this article, we also discuss the recent studies on the relationship between asymmetric papilledema and optic canal size.

Primary empty sella: The risk factors and associations with the cerebral small vessel diseases-An observational study

OBJECTIVE

To investigate the risk factors of primary empty sella (PES) and its associations with cerebral small vessel diseases (CSVD).

METHODS

A total of 132 consecutive patients were recruited from Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University from December 2018 to January 2020, including 69 cases of PES, and age, gender-matched 63 subjects without PES. Demographics and clinical characteristics were recorded. Enlarged perivascular spaces (PVS) and white matter hyperintensities (WMH), which are image markers for CSVD, were assessed. Univariate logistic regression models and multivariate logistic regression models were performed to predict the independent risk factors of PES.

RESULTS

There was a significant difference in baseline characteristics in terms of hypertension (p < 0.001) and pregnancy (p = 0.019) between PES and the control group; among markers of CSVD, whole WMH (p = 0.030) and periventricular hyperintensities (PVH) (p = 0.027) were significantly different; however, no significant differences concerning deep WMH, total PVS, basilar ganglia-PVS and centrum semiovale-PVS (p > 0.05). After adjusting relevant potential confounders, multivariate logistic regression revealed hypertension (OR=3.158, 95 %CI: 1.452∼6.865, p = 0.004) and pregnancy (OR=2.236, 95 %CI: 1.036-4.826, p = 0.040) were independent risk factors for PES.

CONCLUSION

Hypertension and pregnancy are independent risk factors of PES. There is a possible correlation between PES and WMH, especially PVH, however, further studies are required to confirm these findings.

Outcomes after mini-craniotomy middle fossa approach combined with mastoidectomy for lateral skull base defects

PURPOSE

Controversy exists regarding the ideal approach for repair of lateral skull base defects. Our goal is to report the outcomes following middle cranial fossa (MCF) mini-craniotomy combined with mastoidectomy for patients with superior semicircular canal dehiscence (SSCD), spontaneous cerebrospinal fluid (CSF) leak, and cholesteatoma.

MATERIALS AND METHODS

A retrospective database from chart review was formed consisting of 97 patients who met surgical criteria: SSCD, spontaneous CSF leak, and cholesteatoma. Mini-craniotomy MCF approach (<4 × 2 cm in size) combined with mastoidectomy was performed. All patients were admitted directly to the ICU postoperatively. Multiple factors were assessed, including need for revision surgery, duration of surgery, length of post-operative stay, and hospital readmission.

RESULTS

Average surgery time was 110 min with no intraoperative complications. The average length of hospitalization was 2 days with an average ICU stay of 1 day. There were no neurologic complications; however, there were 3 inpatient complications (3%) which included 1 patient (1%) that had wound breakdown and 2 patients (2%) that had severe post-operative vertigo. A total of 8 patients (8%) required revision surgery and these were primarily for SSCD. The 30-day readmission rate was 3%.

CONCLUSION

In the current series, all patients that underwent mini-craniotomy MCF surgery combined with mastoidectomy had minimal complications, short surgical time, limited hospital stay, low revision surgery rate and few hospital readmissions. This combined approach offers superior visualization of lateral skull base defects without the morbidity and risk typically associated with traditional, extensive MCF surgery.

Transtemporal Venous Decompression for Idiopathic Venous Pulsatile Tinnitus

Objective To evaluate the clinical characteristics and present surgical outcomes of transtemporal venous decompression technique in the treatment of pulsatile tinnitus (PT).

Study Design This is a prospective cohort study.

Setting This study was done at the tertiary private neurotologic skull base clinic.

Participants The primary author, between March 2012 and February 2013, evaluated 55 patients with the complaint of PT. Seven out of the 55 patients were diagnosed with severe, unrelenting idiopathic pulsatile tinnitus (IPT), and were placed into the study. These seven patients had temporal bone computed tomography, magnetic resonance imaging, arteriogram, videonystagmography, electrocochleography, and lumbar puncture based on the symptoms. All the seven patients underwent transtemporal venous decompression surgery.

Main Outcome Measure Resolution of PT was determined as the primary outcome measure.

Results Six out of seven patients had complete resolution of their PT immediately after surgery and at 3 to 4 years follow-up. One patient developed intracranial hypertension after 3 months requiring ventriculoperitoneal shunt, which resolved PT as well. No complications occurred.

Conclusion A significant subset of the PT patient population has known reversible causes. The more common includes conductive hearing loss, superior canal dehiscence, benign intracranial hypertension, jugulosigmoid venous anomalies, stapedial myoclonus, etc. There exists a subset of patients who have IPT. Transtemporal venous decompression is a surgical technique that can be employed to give patients with IPT long-term relief.

The relationship between spontaneous cerebrospinal fluid leak and idiopathic intracranial hypertension

Surgical treatment of spontaneous cerebrospinal fluid (CSF) leak is now performed by ENT surgeons, endonasal endoscopy being preferred to craniotomy as less invasive. However, it is often the symptom of underlying idiopathic intracranial hypertension, which lies outside the traditional sphere of ENT competence. Surgery is a necessary step, but should not obscure the need to treat the underlying pathology. This treatment is complex, and requires multidisciplinary team-work between otorhinolaryngologist, ophthalmologist, neurologist, neurosurgeon, radiologist, dietician, endocrinologist and psychotherapist. The present update details this multidisciplinary management to which the ENT surgeons must be attentive before and after spontaneous CSF leak repair.

Multiple spontaneous skull base cerebrospinal fluid leaks: some insights from an international retrospective collaborative study

PURPOSE

Spontaneous skull base cerebrospinal fluid leaks occurring without any apparent cause are rare. But those patients that present such leaks simultaneously, or successively, in multiple locations are even rarer. Given the rarity of this condition, we collected data from other groups in a multicentre study to reach an adequate number of patients and draw some preliminary considerations.

METHODS

We carried out a multicentre retrospective study on a cohort of patients treated at third level hospitals in Italy, Spain, United Kingdom and Greece for multiple spontaneous-CSF leaks and we compared them with a control group of patients treated for recurrent spontaneous-CSF leaks. Data regarding clinical aspects, radiological findings, surgical techniques and outcome were collected and preliminary considerations on the results were discussed.

RESULTS

A total of 25 patients presented multiple simultaneous spontaneous CSF leaks while 18 patients fit with the criteria of recurrent spontaneous CSF leaks. Data analysis was conducted separately.

CONCLUSIONS

Our understanding of the pathogenesis of this condition is currently very limited. A causative role of IIH may be present but the differences that emerged from the comparison with patients with recurrent fistulas seem to promote the possible role of other cofactors. A longer follow-up period is needed, and, in our opinion, prospective and multicentre studies are the only solution to seriously deal with such a complex topic.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Middle Cranial Fossa Repair of Temporal Bone Spontaneous CSF Leaks With Hydroxyapatite Bone Cement

OBJECTIVES

To determine the safety and effectiveness of the middle cranial fossa (MCF) approach in repairing spontaneous cerebrospinal fluid (sCSF) leaks.

STUDY DESIGN

Retrospective cohort study.

METHODS

Patient with sCSF leaks repaired by MCF approach between January 1, 2014 and August 31, 2019 were included. Demographic information, clinical and surgical findings, and postoperative outcomes were recorded.

RESULTS

The cohort (n = 45) included 24 tegmen repairs by multilayer reconstruction using hydroxyapatite cement and 21 cases of multilayer repair without hydroxyapatite cement. Ten MCF repairs were performed on patients ≥65 years old. Twenty (53%) ears had multiple tegmen defects (range, 1-9 tegmen defects) and 78% of patients had ≥1 encephaloceles. All sCSF leaks were resolved with one surgical intervention. There were no major intracranial complications. Transient expressive aphasia occurred in 2 patients. Medical complications occurred in four patients. There were no short-term postoperative CSF leaks with bone cement reconstruction and two postoperative leaks without bone cement. One resolved with lumbar drain (LD) and the other resolved without treatment. The average (SD) length of stay (LOS) with bone cement was shorter than in patients without bone cement (2.54 [0.83] days vs. 3.52 [1.99] days, P < .05). There have been no long-term CSF leak recurrences with an average (SD) follow-up of 13.5 (12.9) months (range 0.25-46 months).

CONCLUSIONS

MCF approach for sCSF repairs demonstrate efficacious outcomes, particularly with tegmen reconstruction using hydroxyapatite cement. The approach exhibited no serious adverse events and few complications requiring intervention. Therefore, MCF is a safe and effective approach to resolve sCSF leaks.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:624-632, 2021.

Hemifacial Spasm as a Rare Clinical Presentation of Idiopathic Intracranial Hypertension: Case Report and Literature Review

OBJECTIVES

To report a rare case of idiopathic intracranial hypertension (IIH) presenting with hemifacial spasm (HFS) and review the current literature.

METHODS

Case report and literature review. The patient's medical record was reviewed for demographic and clinical data. For literature review, all case reports or other publications published in English literature were identified using PUBMED.

RESULTS

A 43-year-old obese female presented with a 2-year history of left HFS.Electroencephalography and head computed tomography were unremarkable. Magnetic resonance imaging demonstrated bilateral anterior inferior cerebellar artery vascular loops involving the internal auditory canals as well as IIH-associated findings. A lumbar puncture was performed and revealed an elevated opening pressure of 26 cm H₂0 cerebrospinal fluid. Acetazolamide treatment was then initiated, resulting in complete resolution of the HFS.

CONCLUSION

HFS may be a rare presenting manifestation of IIH, and treatment of IIH may result in improvement of HFS symptoms. This is the first report of IIH presenting with HFS in the absence of headache or visual change. As a result, this is the first report of HFS as a presenting manifestation of IIH in Otolaryngology literature.

Spontaneous cerebrospinal fluid leak and idiopathic intracranial hypertension

PURPOSE OF REVIEW

To review the most recent literature on the relationship of spontaneous cerebrospinal fluid (CSF) leak with idiopathic intracranial hypertension (IIH) and considerations in management of these conditions.

RECENT FINDINGS

A link has been proposed between spontaneous CSF leak and IIH based on similar demographics, radiologic, and clinical findings in these patients, and on a plausible mechanism of skull base erosion in the setting of high CSF pressure over time. IIH patients with CSF leak may not present with classic IIH signs and symptoms as the leak can alleviate excess pressure; however, they may develop these after a leak is repaired. There may also be a higher risk of leak recurrence if intracranial hypertension is not treated postoperatively.

SUMMARY

A growing body of evidence supports an association between IIH and spontaneous CSF leak. However, this relationship is still not fully elucidated, and there is no current agreement on how to incorporate screening, management, or counseling guidelines for CSF leak into the care of IIH patients. There are also no specific guidelines for evaluation/management of IIH in patients with spontaneous CSF leak. Further interdisciplinary research is needed to explore this connection and to establish screening, evaluation, and management guidelines.

Impact of Obesity and Obstructive Sleep Apnea in Lateral Skull Base Cerebrospinal Fluid Leak Repair

OBJECTIVE

To investigate the prevalence and impact of obstructive sleep apnea (OSA) and obesity in lateral skull base cerebrospinal fluid leak repair (LSBR) of various etiologies.

METHODS

Retrospective case review at a tertiary skull base center was conducted of consecutive adults undergoing LSBR via transmastoid, middle cranial fossa, or combined approach between 2013-2018. The following data were collected: demographics, comorbidities, radiology and intraoperative findings, and surgical outcomes including complications and need for revision surgery or shunt placement. Patients with incomplete data or leaks following skull base surgery, trauma or chronic ear disease were excluded.

RESULTS

Ninety-four patients (67.4% female, mean age 53.5 ± 12.9 years) underwent repair for spontaneous (sCSFL, 44%) and other etiology (nsCSFL) leaks. nsCSFL served as a comparison group consisting of leaks status-post lateral skull base surgery, temporal bone fractures, and chronic ear disease. Class III obesity (P = .02), OSA (P = .03), and imaging findings of empty sella (OR = 3.32, P = .02), and skull base thinning including contralateral tegmen thinning (31%, OR = 4.3, P = .02), arachnoid granulations (26%, OR = 4.35, P = .02), and superior canal dehiscence (15.8%, OR = 8.57, P = .04) were more common in sCSFL. Four patients (4.2%) required surgical revision for recurrence, and another four (4.2%) resolved with shunting. Evidence of elevated intracranial hypertension was present in nine patients with sCSF leaks and was predictive of need for revision or shunt procedures (P < .01).

CONCLUSION

Obesity, OSA, and imaging consistent with elevated intracranial pressures were more common among patients with sCSFL. Elevated intracranial pressure predicted outcomes following multilayer repair of spontaneous CSF leaks LEVEL OF EVIDENCE: 4 Laryngoscope, 130:2234-2240, 2020.

Endoscopic Endonasal Repair of Spontaneous Cerebrospinal Fluid Leaks Using Multilayer Composite Graft and Vascularized Pedicled Nasoseptal Flap Technique

Background

Endoscopic repair of cerebrospinal fluid (CSF) fistulas is a fundamental practice in anterior skull base surgery due to high success rates and low morbidity profile. However, spontaneous CSF (sCSF) leaks have the highest recurrence rate compared to other etiologies. The most effective management is undetermined due to variations in graft materials and limited evidence.

Objective

We present the largest study of a standardized endoscopic repair technique for sCSF leaks.

Methods

Single-institution retrospective review of patients who underwent endoscopic sCSF leak repair between October 2011 and January 2018. All patients underwent repair using a temporary lumbar drain, intrathecal fluorescein, and multilayer reconstruction using bilayered fascia lata autograft and vascularized nasoseptal flap.

Results

Twenty patients (100% female, mean age: 53.2 years) with 25 separate sCSF leak sites were included. Obesity was present in 15 of 20 patients (mean body mass index [BMI] = 35.3). No patients had previous sinus surgery. Locations of skull base defects included: cribriform plate (44%), ethmoid (32%), lateral sphenoid (12%), and planum sphenoidale (12%). The mean follow-up was 22.8 months and 92% of the leak sites (23/25) were successfully repaired primarily. There were no neurological complications or cases of meningitis. Two patients (mean BMI = 52) with persistent postoperative CSF leaks and elevated intracranial pressure were successfully managed with ventriculoperitoneal shunt placement. BMI was associated with likelihood of repair failure (P = .003).

Conclusions

At our institution, endoscopic repair of sCSF leaks using a composite autograft of fascia and a nasoseptal flap demonstrates high success rates. Elevated BMI was a statistically significant risk factor for revision.

The Bone Mineral Density of the Lateral Skull Base and its Relation to Obesity and Spontaneous Cerebrospinal Fluid Leaks

OBJECTIVES

Evaluate the bone mineral density (BMD) of the lateral skull base by thin sliced computed tomography (CT) scans.Determine the BMD and its relation in patients who are obese or who have spontaneous cerebrospinal fluid (CSF) leaks.

STUDY DESIGN

Blinded retrospective case control series.

SETTING

Tertiary care university setting.

PATIENTS

A control group consisting of age and sex matched non-obese patients were compared with obese and CSF leak patients.

INTERVENTIONS

Three blinded reviewers measured the BMD at multiple locations along the lateral skull base using thin sliced high-resolution CT scans. Additional BMD measurements were obtained from the temporal bone squamosal and otic capsule. The BMD was compared between the groups.

MAIN OUTCOME MEASURE

Lateral skull base BMD in patients who are obese or have CSF leaks as compared with non-obese controls.

RESULTS

Sixty-five (n = 65) patients were included in the study. The control group (n = 21) had a median density along the tegmen of 499.4 (178.8) HU, obese (n = 26) had an average HU of 559.5 (207.2), and CSF leak group (n = 18) had an average 472.9 (154.9), respectively (p = 0.35). The BMD in the temporal bone squamosa (p = 0.07) was not significantly different, however, the otic capsule was denser in the CSF leak group (p = 0.01) compared with the control group or the obese group. The intraclass correlation coefficient of the CT reviewers' measurements were moderate to strong (k = 0.69-0.99).

CONCLUSION

There appears to be no difference between the BMD of the lateral skull base as it relates to obesity or spontaneous CSF leaks compared with normal weight controls. These findings suggest the BMD does not have a significant role in the development of lateral skull base thinning or dehiscence leading to CSF leaks.

Neuro-Ophthalmologic MRI Findings in the Detection of Rhinorrhoea Aetiology

The purpose of this study is to evaluate the importance of neuro-ophthalmological magnetic resonance imaging (MRI) findings in the identification of the aetiology of rhinorrhoea, and the differentiation of spontaneous rhinorrhoea from non-spontaneous rhinorrhoea. MR images of 25 patients with spontaneous and 21 patients with non-spontaneous rhinorrhoea were evaluated for the presence of neuro-ophthalmological findings of intracranial hypertension (IHT). These include optic nerve vertical tortuosity, optic nerve sheath enlargement, flattening of the posterior sclera and optic nerve protrusion, as well as other MRI findings of ICH, such as partial empty sella, dilatation of Meckel's cave and the presence of arachnoid pits. IHT findings were more common in the spontaneous group. Six criteria (optic nerve distention, optic nerve vertical tortuosity, posterior flattening of the sclera, partial empty sella, Meckel's cave dilatation and presence of arachnoid pits) differentiate between patient and control groups. Patients with spontaneous cerebrospinal fluid (CSF) leaks should be evaluated for signs of IHT on MRI, as they are present in the majority of spontaneous CSF leaks and are representative of increased intracranial pressure.

Postoperative management of patients with spontaneous cerebrospinal fluid leak

PURPOSE OF REVIEW

To explore key management principles and outcomes following surgical intervention for spontaneous CSF leaks of the lateral skull base.

RECENT FINDINGS

Outcomes following surgery for spontaneous CSF leaks of the lateral skull base depend on the surgical approach utilized. The approach reported most frequently in the literature is currently the middle fossa approach. Mean leak recurrence rates, regardless of approach, were approximately 6%. The lowest leak recurrence rates were associated with the combined middle cranial fossa-transmastoid approach. A multilayer closure was employed in all of the reviewed investigations, but the choice of reconstructive material did not significantly affect outcomes. Direct surgical complications rates, overall, were low at less than 2%. Meningitis, intracranial hemorrhage, and perioperative seizure activity were only rarely encountered. A concomitant diagnosis of idiopathic intracranial hypertension was found to be associated with increased rates of leak recurrence and sequential leak development at other skull base sites.

SUMMARY

Postoperative management of patients with spontaneous CSF leaks of the lateral skull base has unique challenges. Observation of key treatment principles can lead to good outcomes and limit morbidity. A high index of suspicion should exist for concomitant idiopathic intracranial hypertension.

Hormonal Fertility Therapy as Potential Risk Factor for Cerebrospinal Fluid Leak After Endoscopic Endonasal Surgery: Case Study and Literature Review

BACKGROUND

Endoscopic endonasal approaches have been shown to be as effective as transcranial approaches for sinonasal malignancies involving the skull base. Although they are associated with less risk than an open cranial resection, cerebrospinal fluid (CSF) leaks remain a main concern. Some drugs can raise the intracranial pressure and exacerbate the risk of a postoperative CSF leak. In this case report, we present a 32-year-old woman who was treated via endoscopic endonasal approach for an olfactory neuroblastoma and later underwent fertility preservation treatment with leuprolide, which likely led to a delayed CSF leak.

CASE DESCRIPTION

A 32-year-old woman diagnosed with a large invasive olfactory neuroblastoma underwent resection via an endonasal transcribriform approach and repair of skull base defect using a pericranial flap. Forty-seven days post operation the patient returned, presenting with a clear nasal discharge. Magnetic resonance imaging raised concern for focal flap necrosis, while computed tomography cisternogram revealed a defect in the pericranial flap. The defect was debrided and repaired; a postoperative lumbar drain was placed and showed an opening pressure of 26 cm of water. Discussion with the patient revealed that she received fertility preservation treatment with leuprolide followed by oocyte retrieval 32 days before presentation of her delayed CSF leak.

CONCLUSIONS

Leuprolide or any drug that can potentially increase intracranial pressure should be held for 3 months after surgery or until after a skull base defect has fully healed.

Management of sphenoid lateral recess encephalocoeles

PURPOSE OF REVIEW

Sphenoid sinus lateral recess encephalocoeles (SSLRE) are rare occurrences and pose unique challenges due to limited surgical access for endoscopic endonasal repair and also the lack of consensus on optimal perioperative managements specifically in the spontaneous cases, which are also believed to be a variant of idiopathic intracranial hypertension (IIH). Endoscopic endonasal approaches have largely replaced the transcranial route and the techniques are continuously being refined to reduce the neurovascular morbidity and improve outcome.

RECENT FINDINGS

Transpetrygoid is the most utilized approach with modifications suggested to limit bone removal, exposure and preservation of the neurovascular structures as dictated by the extent of the lateral recess. As more experience is gained, extended transphenoidal techniques were also successfully used for access. Lateral transorbital is a new approach to the lateral recess investigated in cadavers. IIH treatment is still controversial in the setting of SSLRE, but it appears rationale to evaluate, monitor and treat if necessary.

SUMMARY

SSLRE management should be tailored to the specific anatomical variances and cause. Modifications of techniques have been described giving different options to access the lateral recess. Successful repair for spontaneous SSLRE may require treatment of IIH if present, but the long-term outcome is still unclear.

Two cases of pulsatile tinnitus: Key points for the clinician

INTRODUCTION

Pulsatile tinnitus is a sound generated by an acoustic source from within the body, which is perceived by the auditory system of the patient.

CASES SUMMARY

We report two puzzling cases of pulsatile tinnitus with normal ENT examinations: the first was due to a cervical internal carotid artery dissection, and the second to the compression of the foramina of Monro by a craniopharyngioma, leading to hydrocephalus.

DISCUSSION

We review the systematic management and emphasize the decisive role of the ENT clinician regarding this pulsatile tinnitus complaint, because of the potentially severe complications of its underlying pathology.

Ventriculo-peritoneal shunting is a safe and effective treatment for idiopathic intracranial hypertension

PURPOSE

To determine the outcome of ventriculo-peritoneal shunts as a treatment for idiopathic intracranial hypertension (IIH) Materials and Methods: Retrospective case series of 28 patients with IIH and evidence of raised intracranial pressure (ICP) who underwent shunt insertion. Patients were identified from a prospectively updated operative database. A case-notes review was performed and data on type of shunt, pre- and post-operative symptoms, ophthalmological findings and post-operative complications were recorded.

RESULTS

All patients had symptoms of IIH that had failed medical management. Twelve patients had previous lumbo-peritoneal shunts and 2 patients had previous venous sinus stents. All patients had evidence of raised ICP as papilloedema and raised CSF pressure on lumbar puncture. Twenty-seven patients received a ventriculo-peritoneal shunt and 1 patient a ventriculo-atrial shunt. Twenty-six patients received Orbis Sigma Valves and 2 patients Strata valves. At follow-up all patients (100%) had improvement/resolution of papilloedema, 93% had improved visual acuity and 84% had improved headaches. Mean time to last follow-up was 15 (range 4-96) months. Complications occurred in 3 patients (11%): 2 patients required revision of their peritoneal catheters and 1 patient had an anti-siphon device inserted.

CONCLUSIONS

Previous literature reported a ventricular shunt revision rate of 22-42% in the management of IIH. We demonstrate ventriculo-peritoneal shunts to be an effective treatment with a revision rate of 11% compared to the previously reported 22-42%.

Utility of Intracranial Pressure Monitoring for Diagnosis of Idiopathic Intracranial Hypertension in the Absence of Papilledema

BACKGROUND

Idiopathic intracranial hypertension (IIH) is characterized by headaches, visual obscurations, and papilledema, and the diagnosis involves lumbar puncture (LP) with an elevated opening pressure (OP) ≥20 cm H₂0. When papilledema is absent, the diagnosis becomes less clear. Some physicians have argued that the absence of papilledema rules out IIH, whereas others maintain that elevated OP is sufficient for diagnosis.

METHODS

The authors performed a single-institution 4-year retrospective analysis of patients who underwent invasive intracranial pressure (ICP) monitoring for presumed IIH.

RESULTS

A total of 22 patients were reviewed, and 13 had classic symptoms of IIH, documented elevated OP, and absence of papilledema; 5/13 (38%) patients had proven intracranial hypertension as shown by invasive ICP monitoring, whereas 8/13 (62%) had normal ICP.

CONCLUSIONS

With the use of current diagnostic algorithms of clinical presentation and elevated OP, over half of patients without papilledema in our series would be falsely diagnosed with IIH, which could result in unnecessary medical and surgical intervention. Thus, elevated OP as determined by LP is insufficient to diagnose IIH. On the other hand, the absence of papilledema does not rule out intracranial hypertension.

Surgical Outcomes and Postoperative Management in Spontaneous Cerebrospinal Fluid Rhinorrhea

Background  The etiology of spontaneous cerebrospinal fluid (CSF) rhinorrhea remains unknown, though emerging evidence suggests that this likely represents a variant of idiopathic intracranial hypertension. Long-term success rates for repair and postoperative management strategies remain variable. Methods  Retrospective review of patients undergoing surgical management of spontaneous CSF rhinorrhea was conducted over a 5-year period. Analysis was performed to correlate recurrence with demographics and perioperative variables. Lumbar puncture usage and neuro-ophthalmological examinations in clinical management were also assessed. Results  Forty-eight patients were included in the study. The mean age was 51.4 years with 94% females. Leaks were most commonly located in the sphenoid (43.8%) and cribriform region (33.3%). The most common findings on magnetic resonance imaging were empty sella (48%) and Meckel's cave diverticula (24%). Nine patients (18.8%) had recurrent CSF leaks. Six occurred >1 month postoperatively. Three had repeat endoscopic repairs, two received ventriculoperitoneal shunts, and one was managed with a lumbar drain, with overall success rate of 93.8%. Acetazolamide was utilized in 19 cases (39.6%) postoperatively. Overall, 59% of patients had elevated opening pressures on postoperative lumbar puncture ( n  = 32). Neuro-ophthalmology evaluated 28 patients; 25% had visual field deficits, and 7.1% had papilledema. Conclusions  Management of spontaneous CSF leaks remains a significant challenge. Endoscopic repair is successful in most patients with little morbidity; however, postoperative management remains inconsistent, and further studies are warranted to establish consensus on post-surgical care. The association with elevated intracranial pressure and visual field deficits/papilledema suggests opening pressures, and neuro-ophthalmologic evaluation should be considered in the treatment algorithm.