Adult spontaneous CSF otorrhea: correlation with radiographic empty sella

Symptoms Underestimate the Presence of Obstructive Sleep Apnea in Patients with Spontaneous Cerebrospinal Fluid Leaks of the Temporal Bone

OBJECTIVE

To determine the severity of symptoms and degree of obstructive sleep apnea (OSA) in patients with spontaneous cerebrospinal fluid (sCSF) leaks of the temporal bone given the known association between sCSF leaks and OSA.

STUDY DESIGN

Retrospective case review.

SETTING

Ambulatory clinics in tertiary referral centers.

PATIENTS

Polysomnogram testing in 34 consecutive patients who had been diagnosed with sCSF leaks of the temporal bone was examined. Diagnosis of sCSF leak was defined as biochemically confirmed CSF from middle ear fluid with no other obvious source.

INTERVENTION

Diagnostic.

MAIN OUTCOMES MEASURES

Patient characteristics (age, sex, body mass index, Epworth Sleepiness Scale score, presence of hypoxia, overnight change in blood pressure, and apnea hypopnea index [AHI]) were recorded. Diagnosis of OSA was defined as mild when AHI ≥5 and <15/h, moderate when AHI ≥15 and <30/h, and severe when AHI ≥30/h.

RESULTS

Of the 34 patients, 28 (82%) had a confirmed diagnosis of OSA. There was a male predisposition in those with OSA, and 17 of 28 (61%) were male. A majority were overweight, and the mean body mass index was 30.1 (SD, 4.8; range, 23.2-40) kg/m2. The mean severity of OSA was moderate, and the mean AHI was 28.7 (SD, 21.9; range, 5.4-92.8). Of the 28 patients, 13 with OSA (46%) had Epworth Sleepiness Scale scores higher than 8, suggesting that many were asymptomatic for excessive daytime sleepiness at the time of presentation.

CONCLUSION

OSA is highly prevalent among patients with sCSF leaks of the temporal bone. Patients with sCSF leaks irrespective of symptoms of OSA should undergo formal polysomnogram testing.

Expansion of the Foramen Ovale in Patients With Cerebrospinal Fluid Leak or Encephalocele

OBJECTIVE

Spontaneous cerebrospinal fluid (CSF) leaks are associated with elevated intracranial pressure and idiopathic intracranial hypertension (IIH). Skull base erosion and widening of the foramen ovale have been reported in patients with IIH. This study sought to investigate changes in the size of the foramen ovale and foramen spinosum in patients with IIH, spontaneous CSF leak, and encephalocele.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary care academic medical center.

PATIENTS

Adult patients treated from 2014 to 2018 with computed tomographic imaging of the head and who were diagnosed with IIH, encephalocele, or CSF leak.

INTERVENTION

Two blinded observers measured the long and short axes of the foramen ovale and foramen spinosum on axial computed tomographic images. Measurements were used to calculate the approximate elliptical cross-sectional area of the foramina.

MAIN OUTCOME MEASURES

Length, width, and area of the foramen ovale and foramen spinosum.

RESULTS

A total of 264 patients were identified meeting the inclusion criteria and were placed into three groups. There were 170 patients with IIH, 48 with spontaneous CSF leak or encephalocele (CSF/E group), and 46 with traumatic or iatrogenic CSF leak (control group). Mean foramen ovale short axis (4.85 ± 1.00 mm) and cross-sectional area (30.17 ± 9.25 mm2) in the CSF/E group were significantly increased compared with measurements in patients with IIH or the control groups. Foramen ovale size was positively correlated with age in the CSF/E group. No significant difference in foramen spinosum size was found.

CONCLUSION

Skull base defect resulting in spontaneous CSF leak or encephalocele is associated with enlargement of the foramen ovale on axial computed tomography.

A Comparison of Diagnostic Accuracy of Superior Semicircular Canal Dehiscence in MDCT and MRI, and Coexistence with Tegmen Tympani Dehiscence

Objective  Tegmen tympani dehiscence in temporal multidetector computed tomography (MDCT) and superior semicircular canal dehiscence may be seen together. We investigated superior semicircular canal dehiscence in temporal MDCT and temporal magnetic resonance imaging (MRI). Methods  In this retrospective study, 127 temporal MRI and MDCT scans of the same patients were reviewed. In all, 48.8% ( n  = 62) of cases were male, and 51.2% ( n  = 65) of cases were female. Superior semicircular canal dehiscence and superior semicircular canal-temporal lobe distance were evaluated by both MDCT and MRI. Tegmen tympani dehiscence was evaluated by MDCT. Results  Superior semicircular canal dehiscence was detected in 14 cases (5.5%) by temporal MDCT and 15 cases (5.9%) by temporal MRI. In 13 cases (5.1%), it was detected by both MDCT and MRI. In one case (0.4%), it was detected by only temporal MDCT, and in two cases (0.8%), it was detected by only temporal MRI. Median superior semicircular canal-to-temporal distance was 0.66 mm in both males and females in temporal MDCT and temporal MRI. In both temporal MDCT and temporal MRI, as superior semicircular canal-to-temporal lobe distance increased, the presence of superior semicircular canal dehiscence in temporal MDCT and temporal MRI decreased. Tegmen tympani dehiscence was detected in eight cases (6.3%) on the right side and six cases (4.7%) on the left side. The presence of tegmen tympani dehiscence in temporal MDCT and the presence of superior semicircular dehiscence in MDCT and MRI increased. Conclusion  Superior semicircular canal dehiscence was detected by both MDCT and MRI. Due to the accuracy of the MRI method to detect superior semicircular dehiscence, we recommend using MRI instead of MDCT to diagnose superior semicircular canal dehiscence. Moreover, there is no radiation exposure from MRI.

Middle Cranial Fossa Approach to Repair Tegmen Dehiscence Using Self-setting Calcium Phosphate Cement: A Retrospective Case Review

OBJECTIVES

To review the outcomes of repairing tegmen dehiscence using the middle cranial fossa approach with a self-setting bone cement.

STUDY DESIGN

Retrospective case series.

SETTING

Two academic tertiary hospitals.

PATIENTS

All patients presenting for surgical repair of tegmen dehiscence and with postoperative follow-up for at least 6 months between October 2015 and July 2019.

INTERVENTION

Surgical repair using a middle cranial fossa approach using a layered reconstruction with temporalis fascia and self-setting calcium phosphate bone cement.

MAIN OUTCOME MEASURES

Perioperative complications, recurrence of presenting symptoms/disease, hearing, and facial nerve grade.

RESULTS

The cohort consisted of 22 patients with 23 tegmen dehiscence repairs (1 sequential bilateral repair). There were 16 males and 6 females with an average age at operation of 52.6 years. Repairs were left sided in 9, right sided in 12 patients, and bilateral in 1 patient. No patients had recurrence of presenting symptoms or disease at most recent follow-up. Preoperative hearing was maintained in all patients. Two patients (9% of repairs) experienced delayed partial temporary facial nerve weakness House-Brackman grade 2 and 4 which had recovered by 8 weeks postoperative.

CONCLUSION

We demonstrate a technique for repairing tegmen dehiscence of the middle cranial fossa floor that has excellent postoperative outcomes. We highlight potential technical challenges in this approach as well as the need for counseling for potential partial transient facial nerve dysfunction.

Petrous Apex Cephaloceles: Radiology Features and Surgical Management of a Rare Entity

OBJECTIVE

To characterize the radiologic findings of petrous apex cephalocele (PAC) in a patient cohort, and report the surgical management for three symptomatic PAC patients and cerebrospinal fluid (CSF) leak via the middle cranial fossa approach.

STUDY DESIGN

Retrospective case series.

SETTING

Academic center.

PATIENTS

Thirty-five patients with PAC were identified by review of the imaging archive between 2008 and 2019 (29 females; mean, 55 yrs; range, 4-86 yrs). All patients underwent magnetic resonance imaging of the skull base and/or computed tomography examination.

INTERVENTIONS

Surgical repair of PAC.

MAIN OUTCOME MEASURES

Radiologic features of PAC.

RESULTS

Radiological features of PAC: 25.7% bilateral; partial or expanded empty sella in 82.9%; arachnoid pits in 14.2%; and enlarged CSF space of optic nerve sheath in 20.0%. Coexisting pathology included temporal, sphenoid, and bilateral jugular foramen meningocele; as well as cribriform, middle crania fossa, and right temporal defect. Three case studies describing the surgical course of spontaneous CSF leak secondary to PAC were managed with the middle cranial fossa approach.

CONCLUSIONS

PAC is an exceedingly unusual cause for CSF leak in the adult and pediatric population. A middle fossa approach may be used to treat CSF leak as a result of PAC. Typically, CSF otorrhea originates from an encephalocele that extends via a bony defect in the tegmen tympani or tegmen mastoideum. However, on occasion the source of the CSF otorrhea is not via the tegmen, instead defects in the middle fossa floor, medial to the ridge for the gasserian ganglion (tubercle of Princeteau), need to be considered.

The Role of Obesity in Iatrogenic Encephaloceles of the Temporal Bone

OBJECTIVE

Acquired encephaloceles of the temporal bone may be traumatic, spontaneous, or from chronic ear disease or previous surgery. Iatrogenic encephaloceles arise in the setting of previous mastoidectomy and traditionally involve both bony dehiscence and dural injury. We aim to classify and analyze the pathogenesis, clinical presentation, and treatment options for patients with iatrogenic tegmen defects and encephaloceles of the temporal bone.

STUDY DESIGN

Retrospective chart review.

SETTING

Single tertiary academic center.

PATIENTS

Subjects with iatrogenic tegmen defects and encephaloceles of the temporal bone were included.

INTERVENTION

Patient demographics, history, symptoms, radiographic data, intraoperative findings, management, follow-up, and outcomes were recorded.

OUTCOME MEASURES

Primary outcome measures included patient characteristics, time from primary otologic surgery to surgical repair, location of the defect, and management strategy including surgical approach, methods, and follow-up.

RESULTS

Iatrogenic tegmen injuries or encephaloceles were identified in 18 patients and divided into intentional or unintentional. The latter group presented immediately, early, or late, as determined by intraoperative identification or from delayed symptoms. Eleven patients presented late with previously unrecognized encephaloceles. Compared with patients presenting with incidentally noted tegmen dehiscence during revision mastoidectomy, a significant proportion of patients with late encephaloceles had BMI ≥30 kg/m (p = 0.03).

CONCLUSION

The majority of iatrogenic encephaloceles are unintentional, unrecognized, and may present many years after primary surgery. Similar to spontaneous encephaloceles of the temporal bone, obesity is associated with iatrogenic encephaloceles, although the rate of progression and timing is unclear. We recommend primary repair of any unintentional tegmen defect encountered during mastoid surgery, especially in obese patients.

Bilateral Sequential Spontaneous Otogenic Pneumocephalus, Lessons in Pathophysiology, and Management of a Rare Case

OBJECTIVE

Report the details of an unusual case of initially unilateral intradural spontaneous otogenic pneumocephalus in which the patient developed contralateral pneumocephalus after surgical repair of temporal bone and dural defects on the initial side. Discuss the lessons learned concerning management and pathophysiology of this rare case.

PATIENT

A 73-year-old male presenting with bilateral retro-orbital pain and headache was found to have unilateral intradural pneumocephalus in the temporal lobe with an adjacent defect in the temporal bone.

INTERVENTION

Surgical repair of the initial defect in the temporal bone and dura via a middle cranial fossa approach with obliteration of the mastoid cavity.

RESULTS

The patient's symptoms and degree of pneumocephalus on first affected side decreased initially after surgery. Two weeks after surgery he developed worsening pneumocephalus on the contralateral side in the temporal and frontal lobes with weakness and mild somnolence. This side was repaired via a similar technique without mastoid obliteration. Two weeks after surgery the patient recovered to normal level of consciousness with mild residual weakness.

CONCLUSIONS

Spontaneous otogenic intradural pneumocephalus is an extremely rare but serious condition related to defects in the temporal bone and dura. The precise mechanism by which this occurs is poorly understood. This unusual case where there were bilateral defects presenting with spontaneous otogenic pneumocephalus in sequence illustrates that it represents a rare sequelae of processes which thin the skull base. These processes should be addressed in addition to acute management of the defect and intracranial air.

Low incidence of true Sternberg's canal defects among lateral sphenoid sinus encephaloceles

BACKGROUND

Spontaneous sphenoid sinus cerebrospinal fluid (CSF) encephaloceles have been postulated to arise from a persistent Sternberg's canal. However, recent evidence has questioned this embryological etiology. We examined the anatomic location of a series of lateral sphenoid sinus encephaloceles to determine if they corresponded with the location of Sternberg's canal.

METHODS

We queried a prospectively acquired database of surgically treated spontaneous CSF leaks and identified those arising from the sphenoidal sinus. Images were reviewed to characterize the leaks with respect to the foramen rotundum (FR) and the vidian canal (VC). Four leak types were classified of which Type I (medial to FR and VC entering nasopharynx) was theoretically located in the precise location of Sternberg's canal. Type II was medial to FR; Type III was lateral to FR; Type IV passed through an enlarged FR into sphenoid sinus. Demographic data were analyzed.

RESULTS

Of 103 repaired CSF leaks, 17 arose from the lateral sphenoid sinus. There were no true Type I leaks, 3 Type II leaks, 12 Type III leaks, and 2 Type IV leaks. No differences were found with respect to sphenoid pneumatization, BMI, age, sex, arachnoid pits, or postoperative leak between different types.

CONCLUSIONS

No evidence was found to support the existence of a classic Sternberg canal CSF leak, supporting the hypothesis that most sphenoid spontaneous leaks likely occur secondary to chronically elevated ICP. Rare cases may be related to a weakness in the sphenoid wall in the region of Sternberg's canal.

[Exudative otitis media as a manifestation of spontaneous otoliquorrhea]

Spontaneous otoliquorrhea (SOL) often mimics the picture of exudative otitis media (EOM), which leads to delayed diagnosis of the underlying disease.

PURPOSE OF STUDY

Is to evaluate causes, clinical features and diagnostic algorithm for patients with SOL.

PATIENTS AND RESEARCH METHODS

From 2007 to 2018, 33 patients with SOL underwent examination and treatment in the Department of Ear Microsurgery of the Institute. At the preoperative stage, all patients underwent a complete examination, including examination of ENT organs, anthropometric, biochemical, audiological, ultrasound and radiological tests, which made it possible to make the correct diagnosis.

RESULTS

SOL was more likely to occur in women over 50 who are obese (69.7%, stage II-III). The disease onset in 51.6% of patients was preceded by conditions accompanied by a short-term or prolonged increase in intracranial pressure. SOL was manifested by the clinical picture of EOM in 72.7% of cases, only in 45.5% of cases was accompanied by release from the ear and nose, was often intermittent and complicated by meningitis in 12.1% of patients. Difficulties in diagnosing the disease are caused by clinical manifestations of exudative or acute otitis media in the absence of a causative factor, which led to the verification of SOL from 1 to 4 years in 81.9% of patients who received long-term treatment for other ENT diseases.

CONCLUSION

The master factors in the diagnosis of SOL are otomicroscopy and endoscopy of the nasopharynx, Halo test and screening determination of glucose level in the obtained discharge, as well as high-resolution CT of the temporal bone, which allows to localize the cerebrospinal fluid fistula and to determine the size of the defect.

Do Most Patients With a Spontaneous Cerebrospinal Fluid Leak Have Idiopathic Intracranial Hypertension?

BACKGROUND

The association between cerebrospinal fluid (CSF) leaks at the skull base and raised intracranial pressure (ICP) has been reported since the 1960s. It has been suggested that spontaneous CSF leaks might represent a variant of idiopathic intracranial hypertension (IIH). We review the evidence regarding the association between spontaneous CSF leaks and IIH, and the role of ICP in the pathophysiology of nontraumatic skull base defects. We also discuss the management of ICP in the setting of CSF leaks and IIH.

EVIDENCE ACQUISITION

References were identified by searches of PubMed from 1955 to September 2018 with the terms "idiopathic intracranial hypertension" and "cerebrospinal fluid leak." Additional references were identified using the terms "pseudotumor cerebri," "intracranial hypertension," "benign intracranial hypertension," and by hand search of relevant articles.

RESULTS

A CSF leak entails the egress of CSF from the subarachnoid spaces of the skull base into the surrounding cavitary structures. Striking overlaps exist regarding demographic, clinical, and radiological characteristics between IIH patients and those with spontaneous CSF leaks, suggesting that some (if not most) of these patients have IIH. However, determining whether a patient with spontaneous CSF leak may have IIH may be difficult, as signs and symptoms of raised ICP may be obviated by the leak. The pathophysiology is unknown but might stem from progressive erosion of the thin bone of the skull base by persistent pulsatile high CSF pressure. Currently, there is no consensus regarding the management of ICP after spontaneous CSF leak repair when IIH is suspected.

CONCLUSIONS

IIH is becoming more widely recognized as a cause of spontaneous CSF leaks, but the causal relationship remains poorly characterized. Systematic evaluation and follow-up of patients with spontaneous CSF leaks by neuro-ophthalmologists will help clarify the relation between IIH and spontaneous CSF leaks.

Giant Cephalocele Case Mimicking Cystic Neoplasia in Skull Base

Petrous apex cephalocel, also called arachnoid cyst or meningocele, is a rare cephalocele caused by protrusion of the posterolateral wall of the Meckel cave to the petrous apex. Increased intracranial pressure is thought to play a role in etiopathogenesis and is generally asymptomatic. Radiologically, they are expansile lesions with the same density or intensity as cerebrospinal fluid and may mimic cystic masses. The diagnosis is made by showing the continuity with Meckel cave on magnetic resonance imaging. No intervention is required in asymptomatic patients; surgical treatment is applied in symptomatics.

Diagnosis and management of spontaneous cerebrospinal fluid fistula and encephaloceles

PURPOSE OF REVIEW

To describe the current state in the diagnosis and management of spontaneous cerebrospinal fluid (sCSF) fistula and encephaloceles.

RECENT FINDINGS

The increased incidence of obesity has resulted in more cases of sCSF fistula and encephaloceles. Obesity results in increased intracranial pressure and a greater chance of developing a sCSF fistula or encephalocele. Obstructive sleep apnea can also result in transient increase in intracranial pressure and has been shown to be common in patients with sCSF fistula. Treatment of CSF fistula is usually necessary because of the increased risk of meningitis. The use of hydroxyapatite bone cements to repair the temporal bone defects has been described with a high success rate of closing the fistula and a low complication rate. Concurrent superior semicircular canal dehiscent can be seen in up to 15% of cases and should be suspected during the surgical approach to avoid potential sensorineural hearing loss and chronic imbalance.

SUMMARY

sCSF fistula and encephaloceles are an uncommon cause of hearing loss, middle ear effusion, and otorrhea, but should be recognized and repaired because of the risk of meningitis.

In Patients with Unexplained Non-Epidemic Recurrent Meningitis a Direct Communication between the Subarachnoid Space and the Outside Must Be Sough

Cerebrospinal fluid (CSF) rhinorrhea is not an uncommon condition, and it may lead to recurrent attacks of meningitis. The detection of the leakage site is an essential part of the investigations performed for the patient. In some cases, an anterior skull base site cannot be detected despite continuous leakage. In these cases, a more distal site must be sought. Furthermore, in some cases, the leakage occurs in the temporal bone. In such patients, a history of hearing loss or previous ear complaints indicates a hidden CSF otorhinorrhea. We present two adult cases of congenital hearing loss due to unilateral inner ear anomalies who presented later in life with repeated meningitis attacks and CSF otorhinorrhea.

Deossification of the Otic Bone in High Pressure CSF Otorhinorrhea: A New Radiological Finding

To highlight a new radiological feature in a patient with labyrinthine malformation presenting with bilateral spontaneous high pressure cerebrospinal fluid (CSF) otorhinorrhea. Study design-retrospective case review. Setting-academic, tertiary cochlear implant center. A cochlear implantee with Incomplete Partition Defect (Type 1) presented with meningitis and CSF otorhinorrhea for which she initially underwent medical treatment. High resolution computed tomography (HRCT) of the temporal bone with CT cisternography was performed for identifying the site of the CSF leak. HRCT and CT cisternography revealed a defect in the region of the stapes foot plate and marked thinning/deossification of the cochlear promontory. These two findings were absent in the pre-implant imaging of the patient done 3 years ago. Surgery by endaural approach was undertaken to close the site of CSF leak. Intraoperatively, marked thinning of the cochlear promontory was observed, corresponding to 'blue lining' of the labyrinth in otologic surgery. This intraoperative finding indicating high intralabyrinthine CSF pressure correlated well with the imaging findings. Primary surgical repair resulted in successful CSF leak closure followed by theco-peritoneal shunting to prevent recurrence of the leak. The patient is using her cochlear implant and doing well with auditory verbal therapy. She is asymptomatic till date. Thinning and deossification of the otic capsule on HRCT is an important indicator of high CSF pressure in patients with labyrinthine malformations. Our case study highlights the need for heightened radiological and clinical vigilance in this subgroup of patients to predict complications and ensure prompt intervention.

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.

Are Patients with Spontaneous CSF Otorrhea and Superior Canal Dehiscence Congenitally Predisposed to Their Disorders?

Objectives (1) Compare lateral skull base (LSB) height/thickness in patients with spontaneous cerebrospinal fluid otorrhea (CSF), superior canal dehiscence (SCD), acoustic neuromas (AN), and otosclerosis (OTO). (2) Perform correlations between age, body mass index (BMI), sex, and LSB height/thickness. Study Design Case series with chart review. Setting Tertiary referral center. Subjects and Methods Patients with CSF, SCD, AN, and OTO diagnosed from 2006 to 2016 were included if they had high-definition temporal bone computed tomography (CT) and absence of trauma, radiation, chronic ear disease, and/or congenital anomaly. CT-based measurements included LSB height/thickness and pneumatization rates overlaying the external auditory canal (EAC), tegmen tympani (TgT), perigeniculate region (PG), and internal auditory canal (IAC). LSB height/thickness, age, sex, and BMI were statistically correlated. In total, 256 patients and 493 ears (109 CSF, 115 SCD, 269 AN/OTO) were measured. Results Patients with CSF had significantly higher BMIs than the other groups ( P < .001). Patients with CSF and SCD had similar radiographic LSB phenotypes at most measured locations. Both groups exhibited a significantly lower LSB height compared to the AN and OTO groups (mean, 3.9-4.2 mm vs 4.9-5.6 mm; P < .001). Patients with CSF and SCD also demonstrated significantly lower pneumatization rates, as low as 17% to 23% overlaying the PG and IAC ( P < .001). There were no statistically significant correlations found between age, sex, BMI, and LSB height/thickness at any measurement location in any group. Conclusions Patients with CSF and SCD exhibit similar radiographic LSB phenotypes. Age, sex, and BMI do not significantly correlate with LSB height/thickness. These data support the theory that CSF and SCD arise via similar congenital pathoetiologic mechanisms.

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.

Idiopathic intracranial hypertension: Contemporary review and implications for the otolaryngologist

OBJECTIVES

1) Review controversies pertaining to the pathophysiology, diagnosis, and treatment of idiopathic intracranial hypertension. 2) Discuss the evolving role of otolaryngologists in managing this disease and related disorders.

DATA SOURCES

Primary literature review, Centers for Disease Control and Prevention website, International Classification of Headache Disorders, Second Edition.

METHODS

A comprehensive review of the primary literature was performed from 1990 to 2016 utilizing keywords idiopathic intracranial hypertension, pseudotumor cerebri, benign intracranial hypertension, spontaneous cerebrospinal fluid leak, and encephalocele. Articles were included at the discretion of the authors based on novel and/or historical contributions to the literature.

RESULTS

The incidence of idiopathic intracranial hypertension is increasing along with the obesity epidemic. Undiagnosed patients may present to otolaryngologists with pulsatile tinnitus, dizziness, sleep apnea, and spontaneous cerebrospinal fluid leaks. Although diagnosis is predicated upon imaging findings and lumbar puncture, radiographic signs including empty sella, optic nerve dilation, and globe flattening may suggest the diagnosis. The most effective intervention is weight loss combined with acetazolamide. Surgery is reserved for severe or refractory symptoms and can be highly morbid. Otolaryngologists are increasingly responsible for managing a number of secondary disorders including cerebrospinal fluid rhinorrhea and otorrhea. Failure to manage intracranial hypertension may lead to adverse surgical outcomes.

CONCLUSIONS

The knowledge base for idiopathic intracranial hypertension has greatly expanded over the past 25 years. This disease is associated with a number of conditions directly relevant to otolaryngologists. A keen understanding of this disorder and its management may optimize outcomes in a growing number of patients. Laryngoscope, 128:248-256, 2018.

Brain Imaging in Idiopathic Intracranial Hypertension

BACKGROUND

The primary role of brain imaging in idiopathic intracranial hypertension (IIH) is to exclude other pathologies causing intracranial hypertension. However, subtle radiologic findings suggestive of IIH have emerged with modern neuroimaging. This review provides a detailed description of the imaging findings reported in IIH and discusses their possible roles in the pathophysiology and the diagnosis of IIH.

EVIDENCE ACQUISITION

References were identified by searches of PubMed from 1955 to January 2015, with the terms "idiopathic intracranial hypertension," "pseudotumor cerebri," "intracranial hypertension," "benign intracranial hypertension," "magnetic resonance imaging," "magnetic resonance venography," "computed tomography (CT)," "CT venography," "imaging," and "cerebrospinal fluid (CSF) leak." Additional references were identified by hand search of relevant articles. When possible, we extracted the number of patients and control subjects from each study for each radiological finding. When at least 2 studies used the same criteria to define a radiological finding, all patients from these studies were pooled to obtain a mean sensitivity and specificity with 95% confidence interval.

RESULTS

Specific neuroimaging findings may suggest long-standing IIH, including empty sella, flattening of the posterior globes, optic nerve head protrusion, distention of the optic nerve sheaths, tortuosity of the optic nerve, cerebellar tonsillar herniation, meningoceles, CSF leaks, and transverse venous sinus stenosis.

CONCLUSION

Although IIH remains a diagnosis of exclusion, the most recently proposed diagnostic criteria have included neuroimaging findings to suggest IIH when major diagnostic criteria are not fulfilled. However, these findings are not diagnostic of IIH, and their presence is not required for the diagnosis of definite IIH. Their incidental discovery on brain imaging should not prompt invasive procedures, unless other signs of IIH, such as papilledema, are present.

Obesity related complications in surgery

PURPOSE OF REVIEW

This article aims to review relevant implications of obesity and associated comorbid conditions for the otology and neurotology surgical subspecialties.

RECENT FINDINGS

Both the incidence and prevalence of obesity are rising worldwide. This condition, along with its many associated comorbidities, can adversely affect the perioperative management of patients undergoing otologic and neurotologic procedures. Preoperative assessment of the cardiopulmonary system and airway are imperative as compromise of either may lead to death. Physiologic changes found in patients with obesity have been shown to predispose to hemodynamic instability, intolerance of hypoxia, bleeding, thrombo-embolism, poor wound healing, and decreased drug clearance. An 'obesity paradox' may exist in which patients who are overweight or obese may have less perioperative morbidity and mortality. Patients who are underweight or morbidly obese seem to have worse surgical outcomes. Obesity has been associated with intracranial hypertension, risk of cerebrospinal fluid (CSF) leak recurrence, and skull base erosion leading to multiple pathologic conditions. These include spontaneous CSF otorrhea, semicircular canal dehiscence syndrome, and sigmoid sinus diverticulum.

SUMMARY

The obese habitus and physiology significantly affects patients undergoing otologic and neurologic surgeries. A thorough understanding of this condition is paramount to successful outcomes.

Idiopathic temporal bone encephaloceles in the obese patient

Objectives

Our aims were to introduce temporal bone encephalocele (TBE) to the differential diagnosis of persistent middle ear effusion, cerebrospinal fluid otorrhea, or chronic otitis media in obese adults and to demonstrate the basic pathophysiologic principles of morbid obesity as it may lead to the cascade of increased intra-abdominal pressure, increased central venous pressure, benign increased intracranial pressure, and TBE.

Methods

A retrospective review of the medical records was performed to determine the location, nature, and etiology of the encephaloceles identified at our institution from 1989 to 2005. Body mass index was calculated from the patient height and weight data.

Results

Eight patients with spontaneous, idiopathic TBE were identified. Body mass index values ranged from 32.0 to 67.5 kg/m2 with a mean of 48.6 kg/m2. All patients identified with a spontaneous, idiopathic TBE were obese.

Conclusion

TBE is associated with morbid obesity in our population and should be considered in the differential diagnosis when evaluating mastoid and middle ear disease in the morbidly obese. © 2007 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

Association between Lateral Skull Base Thickness and Surgical Outcomes in Spontaneous CSF Otorrhea

OBJECTIVES

(1) Correlate skull base thickness with perioperative outcomes for spontaneous cerebrospinal fluid (CSF) otorrhea. (2) Augment perioperative counseling of patients with abnormally thin skull bases.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary center. Patients with spontaneous CSF otorrhea have thin skull bases. This is associated with obesity and/or idiopathic intracranial hypertension. The influence of skull base thinning on perioperative outcomes is unknown.

SUBJECTS AND METHODS

A retrospective review was conducted from 2004 to 2014. Forty-eight cases of spontaneous CSF otorrhea met the inclusion criteria of primary surgery by the senior authors: preoperative dedicated temporal bone computed tomography, absence of other leak etiologies, and follow-up >6 months. Patients were stratified into thin (<0.9 mm) and thick (>0.9 mm) groups based on computed tomography measures of their tegmen. Primary outcomes measures were as follows: postoperative meningitis, recurrent leak, second site leak (contralateral ear/anterior fossa), and permanent shunt placement. Hearing outcomes were not assessed in this study.

RESULTS

Thirty and 15 patients composed the thin and thick groups, respectively. Both the incidence (P < .0001) and the rate (P = .005) of adverse outcomes were significantly higher in the thin group. Only 2 patients in the thick group experienced an adverse outcome. Eleven patients underwent multiple procedures for spontaneous leaks. The recurrence rate was 14.5%. All but 1 recurrence occurred in the thin group.

CONCLUSIONS

An abnormally thin tegmen was significantly associated with adverse perioperative outcomes in cases of spontaneous CSF otorrhea. A thick skull base and the presence of an encephalocele may be protective against recurrence. The effect of untreated intracranial hypertension on the results is unknown.

Lateral Skull Base Attenuation in Patients with Anterior Cranial Fossa Spontaneous Cerebrospinal Fluid Leaks

Objective

(1) Determine if patients with anterior fossa spontaneous cerebrospinal fluid (SCSF) leaks demonstrate lateral skull base bone attenuation. (2) Examine the relation between body mass index (BMI; kg/m2) and skull base thickness.

Study Design

Retrospective cohort study.

Setting

Tertiary care hospital.

Subjects and Methods

Retrospective review from 2004 to 2013 identified 96 patients with anterior cranial fossa SCSF leaks. A control group was identified from a consecutive series of clinic patients. Controls had no history of chronic sinonasal or temporal bone pathology and were divided according to BMI into nonobese (<30 kg/m2) and obese (≥30 kg/m2) groups. Composite skull base thickness was calculated for lateral and anterior subsites through predefined points according to previously published protocols.

Results

Thirty-two patients were included in each group. Composite lateral skull base thickness was less in patients with SCSF leaks(0.7 ± 0.1 mm) when compared with nonobese controls (0.8 ± 0.1 mm, P = .004); no differences were apparent when SCSF leaks were compared with obese controls (0.7 ± 0.1 mm, P = .99). A direct relation was observed between anterior skull base and lateral skull base thickness ( r = 0.48, P < .0001). An inverse correlation was noted between BMI and lateral skull base ( r =−0.40, P < .0001).

Conclusions

Patients with anterior fossa SCSF leaks demonstrate attenuation of the lateral skull base. A significant correlation between anterior skull base thickness and lateral skull base thickness was observed. BMI was inversely related to lateral skull base thickness. Taken together, SCSF leaks are associated with obesity, which appears to be partly responsible for diffuse skull base erosion observed in patients with this condition.

Petrous apex cephalocoele: contribution of coexisting intracranial pathologies to the aetiopathogenesis

OBJECTIVE

The aim of this study was to show the MRI findings of petrous apex cephalocoele (PAC) and the other intracranial pathologies that coexist with PAC, and to discuss the contribution of the co-existing pathologies to aetiopathogenesis.

METHODS

A retrospective analysis of our imaging archive for the period from January 2012 to October 2013 revealed 13 patients with PAC (12 females and 1 male; age range, 26-69 years). 11 patients underwent MRI examination of the cranium, and 2 patients underwent MRI examination of the sellar region. We evaluated the lesions for content, signal intensity, enhancement, relation to petrous apex and Meckel's cave. Images were also evaluated for coexisting pathologies.

RESULTS

The presenting symptoms included headache, vertigo, cerebrospinal fluid (CSF) leak and trigeminal neuropathy. All patients had PAC. All lesions were located posterolateral to the Meckel's cave and were isointense with CSF signal on all pulse sequences. All lesions were continuous with Meckel's cave. Coexisting pathologies included intracranial aneurysmal dilatation, empty sella, mass in hypophysis, arachnoid cyst, inferior herniation of parahippocampal gyrus and optic nerve sheath CSF distension.

CONCLUSION

Coexistence with other intracranial pathologies supports the possibility of CSF imbalance and/or intracranial hypertension in the aetiopathogenesis of PAC.

ADVANCES IN KNOWLEDGE

This study examined the contribution of the co-existing intracranial pathologies to the aetiopathogenesis of PAC.

Novel radiographic measurement algorithm demonstrating a link between obesity and lateral skull base attenuation

OBJECTIVES

(1) To describe a validated algorithm for measuring tegmen thickness on computed tomography scans. (2) To compare the tegmen thickness in 3 groups: patients with spontaneous cerebrospinal fluid (CSF) leaks, obese controls, and nonobese controls.

STUDY DESIGN

Retrospective review.

SETTING

Patients with spontaneous CSF otorrhea often have highly attenuated tegmen plates. This is associated with obesity and/or idiopathic intracranial hypertension (IIH). No evidence exists, however, that objectively links obesity and/or IIH with skull base attenuation.

SUBJECTS AND METHODS

This was a retrospective review from 2004 to the present. Patients with spontaneous CSF otorrhea and matched obese (body mass index [BMI] >30 kg/m(2)) and nonobese (BMI <30 kg/m(2)) controls were selected. Tegmen thickness was measured radiographically. Interrater validity was assessed.

RESULTS

Ninety-eight patients were measured: 37 in the CSF group (BMI, 36.6 kg/m(2)), 30 in the obese group (BMI, 34.6 kg/m(2)), and 31 in the nonobese group (BMI, 24.2 kg/m(2)). The CSF group had a significantly thinner tegmen compared to both the obese control (P < .01) and nonobese control (P = .0004) groups. Obese controls had a thinner tegmen than nonobese controls (P < .00001). A significant inverse correlation was detected between skull base thickness and BMI. Signs/symptoms of IIH were most commonly found in the CSF group. Good to very good strength of agreement was detected for measures between raters.

CONCLUSION

This is the first study to (1) quantify lateral skull base thickness and (2) significantly correlate obesity with lateral skull base attenuation. Patients who are obese with spontaneous CSF leaks have greater attenuation of their skull base than matched obese controls. This finding supports theories that an additional process, possibly congenital, has a pathoetiological role in skull base dehiscence.

ICP, BMI, surgical repair, and CSF diversion in patients presenting with spontaneous CSF otorrhea

OBJECTIVE

To assess intracranial pressure (ICP), body mass index (BMI), surgical repair, and cerebrospinal fluid (CSF) diversion in patients presenting with spontaneous CSF otorrhea.

STUDY DESIGN

Retrospective series review.

SETTING

Tertiary referral center.

PATIENTS

Thirty-two patients were treated surgically from 2004 to 2013 for spontaneous CSF otorrhea by the principal investigators. Patients with a history of chronic ear disease and cholesteatoma, previous mastoid surgery, head trauma, or iatrogenic injury were excluded. Average age was 56 years. Twenty-two patients (69%) were female.

INTERVENTION(S)

Middle fossa repair, transmastoid repair, lumbar puncture, V-P shunt, L-P shunt, and magnetic resonance imaging.

MAIN OUTCOME MEASURE(S)

Patients underwent middle fossa or transmastoid repair of tegmen defects. Intracranial pressures were determined with lumbar puncture at time of surgical repair or shortly after surgery. CSF diversion procedures were performed in patients who were found to have elevated ICP, which was not controlled medically, presented with recurrent leak or had ICP of 25 cm or greater of H2O. Preoperative BMI was calculated.

RESULTS

Thirty-two patients underwent 37 operations. Average BMI was 35.0 kg/m2 (median, 34.7; range, 18.7-53.2 kg/m2). There were 21 repairs on the left and 16 on the right. The majority underwent a middle fossa craniotomy for repair (27/32). Two patients had bilateral repairs. Three patients (8%) underwent revision surgery, of which, 2 had untreated intracranial hypertension (ICP 24.5 and 24 cm H2O). ICP measurements were available for 29 patients. The mean ICP was 23.4 cm H2O (median, 24; range, 13-36 cm H20). Twenty-two patients (69%) had ICP of 20 cm or greater of H20; of those, 13 had an ICP of 25 cm or greater of H20. Seventeen patients (53%) underwent CSF diversion procedures.

CONCLUSION

Our findings of elevated ICP and BMI in patients presenting with spontaneous CSF otorrhea are consistent with previous reports in the literature. The percentage of patients that underwent CSF diversion procedures was high at 53% and represents an aggressive stance in managing elevated ICP in a population that may be at risk for subsequent leaks.

Management of spontaneous cerebrospinal fluid leaks of the sphenoid sinus: our experience

BACKGROUND

Closure of spontaneous sphenoid sinus cerebrospinal fluid leaks can be challenging because of the relative inaccessibility of the lateral recess and the presence of intracranial hypertension. We present our experience of such cases and highlight factors associated with a successful outcome.

METHODS

Eleven patients with spontaneous, laboratory confirmed, sphenoid sinus cerebrospinal fluid leaks were included. All patients underwent endoscopic closure by either a three-layer technique or fat obliteration.

RESULTS

In all but one patient, the leak was successfully sealed (success rate, 90.9 per cent; mean follow up, 37.1 months). Elevated intracranial pressure was measured in eight patients, two of whom did not exhibit relevant clinical or radiological characteristics. Five patients received diuretics and dietary advice for weight reduction. In one patient with recurrence two weeks after repair, successful revision was performed by additional placement of a ventriculoperitoneal shunt (follow up, 67 months).

CONCLUSION

Long-lasting cerebrospinal fluid fistula sealing in the sphenoid sinus requires stable reconstruction of the defect in three layers or fat obliteration if the anatomy is unfavourable. All patients should be intra- and post-operatively screened for elevated intracranial pressure to identify those who need additional intracranial pressure reduction measures.

Primary spontaneous cerebrospinal fluid leaks and idiopathic intracranial hypertension

INTRODUCTION

Idiopathic intracranial hypertension (IIH) is increasingly recognized as a cause of spontaneous cerebrospinal fluid (CSF) leak in the otolarnygological and neurosurgical literature. The diagnosis of IIH in patients with spontaneous CSF leaks typically is made a few weeks after surgical repair of the leak when symptoms and signs of elevated intracranial pressure (ICP) appear.

METHODS

Case reports and literature review. Two young obese women developed spontaneous CSF rhinorrhea related to an empty sella in one and a cribriform plate encephalocele in the other. Both patients underwent surgical repair of the CSF leak. A few weeks later, they developed chronic headaches and bilateral papilledema. Lumbar punctures showed elevated CSF opening pressures with normal CSF contents, with temporary improvement of headaches. A man with a 3-year history of untreated IIH developed spontaneous CSF rhinorrhea. He experienced improvement of his headaches and papilledema after a CSF shunting procedure, and the rhinorrhea resolved after endoscopic repair of the leak.

RESULTS

These cases and the literature review confirm a definite association between IIH and spontaneous CSF leak based on: 1) similar demographics; 2) increased ICP in some patients with spontaneous CSF leak after leak repair; 3) higher rate of leak recurrence in patients with raised ICP; 4) patients with intracranial hypertension secondary to tumors may develop CSF leak, confirming that raised ICP from other causes than IIH can cause CSF leak.

CONCLUSIONS

CSF leak occasionally may keep IIH patients symptom-free; however, classic symptoms and signs of intracranial hypertension may develop after a CSF leak is repaired, exposing these patients to a high risk of recurrence of the leak unless an ICP-lowering intervention is performed.

Combined approach for tegmen defects repair in patients with cerebrospinal fluid otorrhea or herniations: our experience

Objectives To describe our departmental experience in the surgical repair of tegmen tympani defects using a combined transmastoid/minicraniotomic approach. Design Retrospective review of videos from surgery and patients' charts. Setting Tertiary university referral center. Participants Twenty-two patients who underwent surgical repair of tegmen defects associated with cerebrospinal fluid (CSF) leakage and/or meningocele/meningoencephalocele by a combined transmastoid/minicraniotomic approach. Main Outcome Measures A retrospective review of videos of surgery and charts of patients with tegmen tympani or tegmen antri defects and CSF leakage, temporal lobe encephalocele, and/or meningoencephalocele. Results All patients underwent the combined approach and had their defects closed, without significant intraoperative or postoperative complications. Conclusions Mastoidectomy with temporal minicraniotomy represents an effective approach in patients with tegmen tympani dehiscence; the advantages of this technique are the control of the floor of the middle cranial fossa and the possibility to reach bony defects located anteriorly without manipulation of the ossicular chain and temporal lobe.

Recurrent meningitis secondary to a petrous apex meningocele

This case report describes a patient who was found to have a cerebrospinal fluid (CSF) leak originating from the petrous apex. The patient initially presented with multiple bouts of meningitis. The patient was treated surgically via a middle cranial fossa approach but presented five years later with recurrent meningitis and was found to have an osseous defect of the petrous apex which was not recognized prior to the initial surgery.

Spontaneous lateral sphenoid cephaloceles: anatomic factors contributing to pathogenesis and proposed classification

SUMMARY

Spontaneous lateral sphenoid cephaloceles arise from bony defects in the lateral sphenoid, in the absence of predisposing factors such as trauma, surgery, mass, or congenital skull base malformation. We reviewed CT and MR imaging findings and clinical data of 26 patients with spontaneous lateral sphenoid cephaloceles to better understand anatomic contributions to pathogenesis, varying clinical and imaging manifestations, and descriptive terminology. Two types of spontaneous lateral sphenoid cephaloceles were identified. In 15 of 26 patients, a type 1 spontaneous lateral sphenoid cephalocele was noted, herniating into a pneumatized lateral recess of the sphenoid sinus, and typically presenting with CSF leak and/or headache. In 11 of 26 patients, a type 2 spontaneous lateral sphenoid cephalocele was noted, isolated to the greater sphenoid wing without extension into the sphenoid sinus, presenting with seizures, headaches, meningitis, cranial neuropathy, or detected incidentally. All patients had sphenoid arachnoid pits, and 61% of patients had an empty or partially empty sella, suggesting that altered CSF dynamics may play a role in their genesis.

Transmastoid approach to spontaneous temporal bone cerebrospinal fluid leaks: hearing improvement and success of repair

OBJECTIVE

To determine whether the transmastoid approach to repair of spontaneous temporal bone cerebrospinal fluid (CSF) leak is safe and effective and if improvement in conductive hearing loss is an achievable goal with this approach.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary academic medical center.

SUBJECTS AND METHODS

Fifteen consecutive patients (16 ears) presented with spontaneous temporal bone CSF leaks over a 6-year period. Clinical data, imaging, audiometry, operative reports, and postoperative course were reviewed.

RESULTS

Median age was 59.5 years. Mean body mass index was 40.7 kg/m2. All presented with chronic otorrhea after tympanostomy tube placement and conductive/mixed hearing loss. The mean preoperative air-bone gap was 19 dB. A transmastoid approach alone was used in 15 cases; 1 underwent middle fossa craniotomy. Most defects were located in the tegmen mastoideum and tympani. All repairs were multilayered, typically using autologous mastoid bone, temporalis fascia, and tissue sealant. Primary repair was successful in 15 cases; 1 patient with persistent postoperative otorrhea subsequently underwent middle fossa craniotomy, but no frank leakage was found. No serious complications were encountered. Following transmastoid repair, postoperative audiograms were available for 14 patients. The mean improvement in air-bone gap was 12 dB. Closure of the air-bone gap to ≤12 dB occurred in 100% of cases.

CONCLUSION

The transmastoid approach to repair of spontaneous temporal bone CSF leak is highly successful. Furthermore, patients in this series had excellent hearing results with closure of their air-bone gap to ≤12 dB, which has not been previously described.

Spontaneous cerebrospinal fluid effusion of the temporal bone: repair, audiological outcomes, and obesity

OBJECTIVES/HYPOTHESIS

Spontaneous occurrence of otogenic cerebrospinal fluid (CSF) effusion is now far more prevalent than causes related to infections, prior surgeries, or trauma-trends that may be increasing because of higher rates of obesity and improved diagnostic awareness. In our patient cohort with spontaneous CSF effusion, we report its association with obesity and audiological findings before and after surgery.

STUDY DESIGN

Retrospective study.

METHODS

In our 45 patients (46 ears) with CSF effusion (with or without lateral skull base meningoencephaloceles), we report clinical data, imaging studies, audiogram results, operative techniques, and recurrence rates. Causes included 33 spontaneous, 10 due to chronic otitis media, one iatrogenic, and one traumatic.

RESULTS

Body mass index (BMI) averaged 35 overall (37 for spontaneous type and 32 for nonspontaneous type). Surgical repair of skull base defect was performed using three middle fossa approaches, 24 combined transmastoid/middle fossa, and 19 transmastoid alone. Overall recurrence of CSF leaks was 6.5%. Thirty patients had audiograms available. Sensorineural hearing loss occurred in 10% of patients. Air-bone gap improved by ≥ 15 dB in 20% of patients and worsened by ≥ 15 dB in 6.7% of patients.

CONCLUSION

Patients with spontaneous CSF effusion had a BMI higher than in the nonspontaneous group, but the difference was not statistically significant. However, the dramatic trend toward spontaneous CSF effusion heightens the need for clinician's acumen for diagnosis, particularly in overweight/obese patients. Our audiological outcomes confirm the efficacy of surgical approaches in correcting conductive hearing loss and preserving bone conduction, although hearing loss is a risk during surgical repair.

LEVEL OF EVIDENCE

4. Laryngoscope, 124:1204-1208, 2014.

Elevated intracranial pressure in patients with spontaneous cerebrospinal fluid otorrhea

OBJECTIVES/HYPOTHESIS

To determine the prevalence of elevated intracranial hypertension in patients with spontaneous cerebrospinal fluid otorrhea (SCSFO).

STUDY DESIGN

Case series with chart review at a tertiary care academic medical center following institutional review board approval.

METHODS

A retrospective review was performed of patients undergoing operative repair of SCSFO between January 2007 and May 2012.

RESULTS

Thirty-eight patients underwent operative repair of SCSFO. Of these, 22 underwent postoperative lumbar puncture with measurement of opening pressure. The opening pressure was elevated (> 20 cm/H2 0) in eight patients (36.4%). Preoperative magnetic resonance imaging was available for review by a neuroradiologist in 27 patients. Radiographic evidence of elevated intracranial pressure (ICP) was present in 48.1% of patients.

CONCLUSION

Elevated ICP is common in patients with SCSFO. However, as only a minority of patients have elevated ICP, it is not the sole factor in the development of SCSFO.

Association of benign intracranial hypertension and spontaneous encephalocele with cerebrospinal fluid leak

OBJECTIVE

To determine the incidence of intracranial hypertension in patients with spontaneous encephalocele with cerebrospinal fluid (CSF) leak.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary care neurotology practice.

PATIENTS

Patients presenting between 2008 and 2011 with spontaneous encephalocele and CSF leak in the temporal bone.

INTERVENTION(S)

Lumbar puncture with opening pressure measurement after encephalocele repair.

MAIN OUTCOME MEASURES

Patient age, sex, postoperative course, body mass index, and postoperative intracranial pressure.

RESULTS

Of the 26 patients identified with spontaneous encephalocele with CSF leak, 9 patients had postoperative lumbar puncture data. Of those 9, 89% were female subjects, and 11% were male, with a mean age of 57 and a mean BMI of 41 kg/m (morbidly obese). The mean opening pressure was 24.5 cm H(2)O. Approximately 33% had normal intracranial pressure (mean, 15 cm H(2)O; range, 10-17 cm H(2)O); 67% had elevated intracranial pressure (mean, 29 cm H(2)O; range, 23.5-40 cm H(2)O). The incidence of BIH in the general population is 0.001%. Of the 6 with intracranial hypertension, 3 (50%) were placed on acetazolamide for fundoscopic findings, postoperative headache, and/or visual changes. Mean time to LP after repair of encephalocele was 13 months (range, 4 days to 75 months).

CONCLUSION

This study shows that benign intracranial hypertension is prevalent in a significant number of patients presenting with spontaneous encephalocele with CSF otorrhea at a rate much higher than is found in the general population. This finding has direct clinical implications and suggests that all patients with spontaneous encephalocele/CSF leak warrant evaluation for benign intracranial hypertension.

Surgical management of temporal meningoencephaloceles, cerebrospinal fluid leaks, and intracranial hypertension: treatment paradigm and outcomes

OBJECT

Thinning of the tegmen tympani and mastoideum components of the temporal bone may predispose to the development of meningoencephaloceles and spontaneous CSF leaks. Surgical repair of these bony defects and associated meningoencephaloceles aids in the prevention of progression and meningitis. Intracranial hypertension may be a contributing factor to this disorder and must be fully evaluated and treated when present. The purpose of this study was to establish a treatment paradigm for tegmen defects and elucidate causative factors.

METHODS

The authors conducted a retrospective review of 23 patients undergoing a combined mastoidectomy and middle cranial fossa craniotomy for the treatment of a tegmen defect.

RESULTS

The average body mass index (BMI) among all patients was 33.2 ± 7.2 kg/m(2). Sixty-five percent of the patients (15 of 23) were obese (BMI > 30 kg/m(2)). Preoperative intracranial pressures (ICPs) averaged 21.8 ± 6.0 cm H(2)O, with 10 patients (43%) demonstrating an ICP > 20 cm H(2)O. Twenty-two patients (96%) had associated encephaloceles. Five patients underwent postoperative ventriculoperitoneal shunting. Twenty-two CSF leaks (96%) were successfully repaired at the first attempt (average follow-up 10.4 months).

CONCLUSIONS

Among all etiologies for CSF leaks, those occurring spontaneously have the highest rate of recurrence. The surgical treatment of temporal bone defects, as well as the recognition and treatment of accompanying intracranial hypertension, provides the greatest success rate in preventing recurrence. After tegmen dehiscence repair, ventriculoperitoneal shunting should be considered for patients with any combination of the following high-risk factors for recurrence: spontaneous CSF leak not caused by another predisposing condition (that is, trauma, chronic infections, or prior surgery), high-volume leaks, CSF opening pressure > 20 cm H(2)O, BMI > 30 kg/m(2), preoperative imaging demonstrating additional cranial base cortical defects (that is, contralateral tegmen or anterior cranial base) and/or an empty sella turcica, and any history of an event that leads to inflammation of the arachnoid granulations and impairment of CSF absorption (that is, meningitis, intracranial hemorrhage, significant closed head injury, and so forth).

Spontaneous Cerebrospinal Fluid Leak through the Posterior Aspect of the Petrous Bone

Spontaneous cerebrospinal fluid (CSF) leak through the posterior fossa (PF) aspect of the petrous bone is exceedingly rare. A case series allows analysis of etiologies and how they may differ from the more common middle fossa (MF) route of leakage. The design was a retrospective case series. The setting was a tertiary care institution. A series of three patients with PF spontaneous CSF leaks was identified. High-resolution imaging (CT and MRI) and intraoperative observations were evaluated. Both in this series and in previously reported cases, patients share the demographics typically found in the MF leak population. In our series, two patterns of PF CSF leak were identified: (1) large unilateral with cerebellar encephalocele and (2) small punctate defects just lateral to the endolymphatic sac. Two presented with simultaneous MF and PF leaks suggesting a shared etiology, at least in some cases, with a role for increased intracranial pressure. In spontaneous CSF leaks, it is important to evaluate the posterior petrous bone along with the tegmen. The concomitant appearance of MF with PF leaks points out the risk that repair via MF craniotomy could fail to identify a leakage site in the vicinity of the endolymphatic sac.

Radiographic evaluation of the tegmen in patients with superior semicircular canal dehiscence

OBJECTIVE

To determine a radiographic association between superior semicircular canal dehiscence (SSCD) and tegmen dehiscence (TD).

STUDY DESIGN

Retrospective case-control series.

SETTING

Tertiary referral center.

PATIENTS

Patients seen between 2003 and 2010 with radiographic SSCD were compared with cochlear implant recipient controls.

INTERVENTION

The tegmen and superior semicircular canal were evaluated on computed tomographic temporal bone scans.

MAIN OUTCOME MEASURE

If detected, the widest point of the SSCD was measured. The tegmen was graded on a 5-point scale. After analysis, a radiographic TD was defined as any single area of absent tegmen greater than 5 mm, multiple areas of absent tegmen, or evidence of meningocele. Age, sex, and body mass index were also noted.

RESULTS

Thirty-eight patients with SSCD and 41 cochlear implant controls were identified. Seventy-six percent (29/38) of patients with unilateral or bilateral SSCD had a radiographic TD on at least 1 side compared with 22% (9/41) of the comparison group. Ninety-four percent (7/18) of patients with bilateral SSCD had a TD on at least 1 side. Patients with SSCD had a 10.2 times (p < 0.001) higher odds of having radiographic TD in either ear compared to the controls. Among patients with any SSCD, for every millimeter increase in the width of dehiscence, the relative risk for any TD increased more than 2-fold (odds ratio, 2.5; p = 0.019). Age, sex, and a body mass index greater than 30 did not confound the association between SSCD and TD.

CONCLUSION

There is a strong radiologic association between SSCD and TD, suggesting a similar etiologic process. The tegmen should be carefully evaluated in patients with SSCD. We have also proposed a new system for radiographically grading the integrity of the tegmen.

Management of cerebrospinal fluid otorrhea

INTRODUCTION

Cerebrospinal fluid otorrhea results from an abnormal communication between the subarachnoid space and tympanomastoid compartment; most of them are of traumatic aetiology. They have clinical interest due to the potential risk of meningitis, directly related to the aetiology. Our aim was to show our experience in the management of this process.

METHODS

A total of 17 patients diagnosed and treated for cerebrospinal fluid otorrhea from 2003 to 2011.

RESULTS

In our study, the highest percentage of cases was spontaneous cerebrospinal fluid otorrhea, with a wide clinical presentation. The diagnosis was based on the determination of beta-2-transferrin and radiological studies, especially important for its locator value. The treatment of choice was surgery.

CONCLUSIONS

Cerebrospinal fluid otorrhea is a rare entity in otorhinolaryngological pathology. Its diagnosis is suspected through otorrhea, hearing loss and aural fullness, while computed tomography and magnetic resonance help us to locate the defect. Surgery is the preferred technique, and its success is based on multilayer technology with 2 or more support materials.

Transmastoid approach to temporal bone cerebrospinal fluid leaks

PURPOSE

The aim of the study was to evaluate various presentations and treatment options for spontaneous cerebrospinal fluid (CSF) leakage originating in the temporal bone.

MATERIALS AND METHODS

Clinical data and imaging results for 18 ears (15 patients) presenting with spontaneous CSF leakage originating in the temporal bone were reviewed. Average follow-up period was 13.5 months. The main outcome measure was presence of persistent CSF leak postoperatively. A standard postauricular mastoidectomy was performed.

RESULTS

Fifteen patients diagnosed with spontaneous CSF leakage over an 8-year period including 3 treated for bilateral disease were included in the study. The age ranged between 33 and 83 years. Presenting symptoms included serous otitis media (44%), persistent otorrhea after tympanostomy tube placement (28%), and meningitis (28%). Preoperative diagnosis was made using imaging studies and was substantiated by observation of CSF leakage and dural herniation intraoperatively. Treatment was eustachian tube plugging (5%), mastoidectomy with fat obliteration (61%), middle fossa approach with extradural (17%), intradural repair (5%), or combined middle fossa and transmastoid (TM) approach (11%). Successful treatment was obtained in 17 of the 18 cases. The last 9 patients in the series underwent TM approach alone for repair with no treatment failures.

CONCLUSIONS

Repair of defects in tegmen mastoideum and posterior fossa can be successfully achieved on an outpatient basis without regard to size and multitude of defects via TM approach. This approach obviates the need for a craniotomy or lumbar drain.

Arachnoid granulations of the temporal bone: a histologic study of dural and osseous penetration

HYPOTHESIS

Arachnoid granulations (AG) are more prevalent along the middle fossa surface of the temporal bone, where they produce larger bony defects than those occurring on the posterior surface.

BACKGROUND

Dural and bony defects formed by AGs are proposed to lead to spontaneous meningoencephaloceles and cerebrospinal fluid otorrhea. They most commonly occur at the tegmen and in individuals older than 40 years.

METHODS

Vertically sectioned temporal bones were evaluated using light microscopy to determine AG histology, distribution, and morphometry and to determine the prevalence of AG penetration in the donor population.

RESULTS

AGs were observed to penetrate the dura mater and make direct contact with cortical surfaces in 12.7% of donors in the Johns Hopkins Temporal Bone Collection. AGs occurred at middle fossa sites 13% more frequently than at posterior fossa sites. At middle fossa sites AGs produced significantly larger bony openings and were more likely to be associated with herniating brain tissue. Donors with AGs were significantly older, and all were in the late 30s or older.

CONCLUSION

Erosion of the temporal bone by AGs is not a rare occurrence in the population and becomes increasingly prevalent with age. It is estimated that 14 in 1,000 donors were at greatest risk of eventual cerebrospinal fluid leakage at the tegmen. The age and anatomic distribution described in this study strengthens the notion that AG penetration plays a role in the pathophysiology of spontaneous cerebrospinal fluid leaks and meningoencephaloceles of the temporal bone.

Double skull base defects with primary spontaneous cerebrospinal fluid leaks in a single patient: temporal and sphenoid bones

Primary spontaneous cerebrospinal fluid leaks occurring in the absence of any apparent cause are rare. Patients may present such leaks simultaneously, or successively, in multiple locations. We report here the sixth case of anterior and lateral skull base defects presented in a single patient. Although rhinoliquorrhea and otoliquorrhea were reported separately in the literature, we postulated that the pathophysiology is the same for the whole skull base; obesity seems to contribute to the development of such primary spontaneous cerebrospinal fluid leak. Consequently, management is similar and regular follow-up is very important.

Transtemporal management of temporal bone encephaloceles and CSF leaks: review of 56 consecutive patients

CONCLUSIONS

This report details our experience in the management of 56 consecutive patients with mastoid encephaloceles and cerebrospinal fluid (CSF) leaks. The majority were managed through the transmastoid route with temporalis fascia and calvarial bone graft. Among the patients operated on at least 18 months before analysis, there was a median follow-up of 54 months with no intracranial complications. The average body mass index (BMI) of patients with spontaneous CSF leaks was found to be statistically significantly greater than that of patients with CSF leaks with traumatic, infectious or iatrogenic etiologies.

OBJECTIVES

To investigate the long-term follow-up of patients with spontaneous, iatrogenic, and traumatic temporal bone encephaloceles and CSF leaks to determine the effectiveness of the repair, late intracranial complications, and recurrent lesions.

METHODS

This is a retrospective review from a tertiary care center of 56 consecutive patients managed with CSF otorrhea, encephaloceles, and spontaneous pneumocephalus. All patients were repaired through transtemporal, middle cranial fossa or combined approaches for extradural repair and bone grafting.

RESULTS

Of the 56 consecutive cases, 12 had CSF otorrhea alone, 19 had encephaloceles, and 23 had both. Two patients presented with spontaneous pneumocephalus without CSF leak. Thirty-three patients had spontaneous onset of their lesion without any history of temporal bone surgery or trauma. The average BMI of patients with spontaneous CSF leaks was found to be greater than the average BMI of patients with CSF leaks due to traumatic, infectious or iatrogenic causes. This difference was found to be statistically significant. Six of these had either preceding or subsequent contralateral mastoid or anterior fossa (sphenoid, ethmoid) CSF leak. Intracranial pressure was evaluated in these cases and most underwent VP shunting to reduce their intracranial pressure. Sixteen cases followed previous mastoid surgery or chronic ear disease and seven were attributed to previous temporal bone trauma. Lesions were repaired with the transtemporal approach (42), middle fossa (4), and combined (5) approaches. Five cases required petrosectomy and fat obliteration. There was one recurrent CSF leak 4 years after initial repair; the leak was anterior to the previously placed bone graft.