Cerebrospinal Fluid Leakage from Tegmen Tympani Defects Repaired via the Middle Cranial Fossa Approach

The Role of Lumbar Drains in the Perioperative Management of Primary Spontaneous Temporal Lobe Encephaloceles and Cerebrospinal Fluid Leaks

OBJECTIVE

To examine the role of lumbar drains (LDs) in the success of spontaneous temporal cerebrospinal fluid (CSF) leak and encephalocele repair.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary academic health system.

PATIENTS

Patients undergoing repair of spontaneous temporal lobe encephaloceles or middle fossa CSF leaks during years 2017 to 2023.

INTERVENTIONS

Transmastoid, middle fossa craniotomy, or combination approaches to CSF leak repair.

OUTCOME MEASURES

Failure rate, complication rate, length of stay (LOS), readmission.

RESULTS

Sixty-nine patients were included, with a combination approach performed in 78.3%, transmastoid in 17.4%, and isolated middle fossa craniotomy in 4.3%. Mean body mass index was 33.2, mean bony defect size width was 6.51 mm, and defect locations included the epitympanum, antrum, mastoid, and petrous apex. Multilayer closure with three or more layers was performed in 87.0%. LD was used in 73.9% of cases for a mean duration 2.27 days and was associated with longer LOS (3.27 vs. 1.56 d, p = 0.006) but not with failure rate, complications, discharge destination, or readmission. Only one major complication occurred as a result of the drain, but low-pressure headache was anecdotally common.

CONCLUSIONS

Use of LD in the repair of spontaneous CSF leaks and temporal lobe encephaloceles is associated with longer LOS but not failure rates or other admission-level outcomes.

Meningitis Risk and Role of Prophylactic Antibiotics in Spontaneous Lateral Skull Base CSF Leaks

OBJECTIVE

To review the literature and our institutional experience regarding the risk of meningitis in patients with spontaneous lateral skull base cerebrospinal fluid (sCSF) leaks awaiting surgical repair, and the roles of antibiotic prophylaxis and pneumococcal vaccination, if known.

METHODS

A retrospective chart review and systematic review of the literature was undertaken to identify the incidence of meningitis in patients with sCSF leaks awaiting surgical repair. Adults managed surgically for sCSF leaks at an academic tertiary care center over a 10-year period were included. Data was collected on receipt of prophylactic antibiotics and/or pneumococcal vaccines during the timeframe between diagnosis and surgical repair.

RESULTS

Institutional review identified 87 patients who underwent surgical repair of spontaneous leaks, with a 0% incidence of meningitis over a median duration of 2 months while awaiting surgery (mean 5.5 months, range 0.5-118 months). Eighty-eight percent of patients did not receive prophylactic antibiotics. No studies in the published literature demonstrated the impact of prophylactic antibiotics or pneumococcal vaccine on meningitis risk.

CONCLUSIONS

There appears to be a low risk of meningitis among patients with lateral skull base sCSF leaks awaiting surgery for short durations (≤2 months), even in the absence of prophylactic antibiotics. There is a substantial gap in the published literature assessing the risk of meningitis and roles of antibiotics and vaccination in this patient population, indicating the need for large-scale study to conclusively elucidate the nature of this risk.

Anterior and Lateral Skull Base Spontaneous CSF Leaks: Evaluation of Comorbidities and Treatment Outcomes

OBJECTIVES

To evaluate clinical characteristics and outcomes of patients diagnosed with anterior (ASB) or lateral skull base (LSB) spontaneous cerebrospinal fluid (sCSF) leak.

METHODS

Single center retrospective review of patients diagnosed with sCSF leaks of ASB or LSB between 1/1/2009 and 11/1/2019 (n = 69). Body mass index (BMI), gender, age at diagnosis, origin of CSF leak (ASB vs LSB), surgical approach, lumbar drain use, recurrence, pre-operative diagnosis of diabetes mellitus (DM), and obstructive sleep apnea (OSA) were collected.

RESULTS

69 patients included in this study met criteria for sCSF leak without a traumatic or iatrogenic cause (Female: 51 (74%); average BMI: 37.0 ± 7.9). Forty-eight (70.0%) presented with sCSF leaks of the lateral skull base. All ASB leaks were treated with an endoscopic transnasal approach. Eleven (22.9%) LSB leak patients were treated using transmastoid approaches and 35 (72.9%) patients with a middle cranial fossa approach. Eleven patients (15.9%) reported sCSF leak recurrence. Two patients (9.5%) with anterior skull base and 9 patients (18.8%) with lateral skull base leaks had recurrence. LSB sCSF leaks had a relative risk of 2.192 of recurrence compared to ASB leaks (95% CI: 0.431-11.157, P = .483). A 5.017 times increased risk (95% CI: 1.285-19.583, P = .020) was reported for patients with OSA, while the risks for DM and BMI were 1.351 (95% CI: 0.67-9.105, P = .177) and 1.026 (95% CI: 0.963-1.094, P = .426) respectively. Patients with sCSF leak recurrence had significantly lower lumbar drain use (33.3%) than those without recurrence (72.7%) (P = .049).

CONCLUSION

Spontaneous CSF leak recurrence is complex and multifactorial, and while patients with both DM and OSA had the higher risk of recurrence, OSA is likely an independent clinical risk factor for sCSF leak recurrence in this patient population.

A Comparison of Outcomes Using Combined Intra- and Extradural versus Extradural-Only Repair of Tegmen Defects

Objective  Tegmen tympani or tegmen mastoideum defects involve dehiscence of the temporal bone that can be a source of cerebrospinal fluid (CSF) otorrhea. Herein, we compare a combined intra-/extradural repair strategy with an extradural-only repair as it pertains to surgical and clinical outcomes. Design  A retrospective review from our institution was performed of patients with tegmen defects requiring surgical intervention. Participants  Patients with tegmen defects who underwent surgery (combined transmastoid and middle fossa craniotomy) for repair of tegmen defects between 2010 and 2020 were inclined in this study. Results  A total of 60 patients with 40 intra-/extradural (mean follow-up time: 1,060 ± 1,103 days) and 20 extradural-only (mean follow-up time: 519 ± 369 days) repairs were identified. No major differences in demographic factors or presenting symptoms were identified between the two cohorts. There was no difference in hospital length of stay between the two patient cohorts (mean: 4.15 vs. 4.35 days, p  = 0.8). In the extradural-only repair technique, synthetic bone cement was more frequently used (100 vs. 7.5%, p  < 0.01), whereas in the combined intra-/extradural repair, synthetic dural substitute was used more often (80 vs. 35%, p  < 0.01), with similar successful surgical outcomes achieved. Despite disparities in the techniques and materials used for repair, there were no differences in complication rates (wound infection, seizures, and ossicular fixation), 30-day readmission rates, or persistent CSF leak between the two treatment cohorts. Conclusion  The results of this study suggest no difference in clinical outcomes between combined intra-/extradural versus extradural-only repair of tegmen defects. A simplified extradural-only repair strategy can be effective, and may reduce the morbidity of intradural reconstruction (seizures, stroke, and intraparenchymal hemorrhage).

Surgical management of spontaneous middle cranial fossa defects: a systematic review and meta-analysis of available reconstructive techniques and materials

Different materials and techniques have been proposed for surgical repair of spontaneous middle cranial fossa (MCF) defects. However, conclusive evidence supporting their selection and impact on clinical outcomes is lacking. The study aims to conduct a systematic review and meta-analysis on materials and techniques employed to repair MCF defects and evaluate complications and rates of recurrent cerebrospinal fluid (CSF) leaks. A PRISMA-guided systematic review and meta-analysis were performed using MESH terms and specific keywords including studies published before May 2022. Primary outcomes included recurrence of CSF leak and complication rates by type of reconstructive material and technique utilized. Meta-analyses of proportions were performed using random effects and confidence intervals for individual proportions were calculated using the Clopper-Pearson method. Twenty-nine studies were included (n = 471 cases). Materials employed for repair were categorized according to defect size: 65% of defects were of unknown size, 24% were small (< 1 cm), and 11% were large (≥ 1 cm). Rigid reconstruction (RR) was significantly favored over soft reconstruction (SR) for larger defects (94% of cases, p < 0.05). Complications and recurrent CSF leak rates of SR and RR techniques were comparable for defects of all sizes (p > 0.05). Complication rates reported for these procedures are low regardless of technique and material. RR was universally preferred for larger defects and analysis of complication and recurrence rates did not reveal differences regardless of defect size. While RR was more frequently reported in smaller defects, SR was used by several centers, particularly for smaller MCF floor defects.

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.

Fetal Bovine Collagen Grafts for Repair of Tegmen Defects and Encephaloceles Via Middle Cranial Fossa Approach

To evaluate the use of commercially available allogenic dural graft materials made of fetal bovine collagen, we present an analysis of our case series with use of autologous and allogenic graft materials. Patients who underwent surgical repair of a tegmen tympani defect associated with ipsilateral conductive hearing loss and cerebrospinal fluid (CSF) otorrhea using a middle cranial fossa (MCF) approach from 2004 to 2018 at Loyola University Medical Center were included. Resolution of CSF otorrhea, audiologic outcomes, facial nerve preservation, and surgical complications was analyzed. Thirty-three patients with an average age of 55.3 years (range: 21-78, standard deviation [SD]: 12.9) and body mass index of 34.4 (range: 22-51, SD: 7.4) underwent an MCF repair of a tegmen and dural defect. All patients presented with CSF otorrhea and conductive hearing loss ipsilateral to the defect. Repairs were made with combinations of allograft and autograft in 17 cases, allograft only in 15 cases, and autograft only in 5 cases. Improvement in hearing was noted in 33 cases, and resolution of CSF otorrhea was noted in 36 cases; one patient required repeat surgery which resolved CSF otorrhea. Three patients had minor complications; all these were in the autograft group. The MCF approach coupled with the use of fetal bovine collagen grafts is a safe and viable method to repair tegmen tympani and associated dural defects with salutary outcomes and low morbidity.

Giant Temporal Lobe Abscess in a Patient With Ectodermal Dysplasia

OBJECTIVE

To present the first reported case of a temporal lobe abscess in a patient with ectodermal dysplasia (ED). To increase awareness among neurotologists of the otological manifestations and complications of ED, we describe a conservative approach in comparison with the surgical strategies to repair bony defects of the tegmen tympani.

STUDY DESIGN

Clinical capsule report.

PATIENT

A 44-year-old man with ED presented with retroauricular pain and high-grade fever after Eustachian tube catheterizations to treat an effusive otitis media. Since many signs indicated meningitis, a computed tomography (CT) scan of the brain was performed, and an extensive intraparenchymal mass was detected. Magnetic Resonance Images (MRI) confirmed a brain abscess of the right temporal lobe.

INTERVENTIONS

Surgical drainage of the abscess through craniotomy, antimicrobial therapy, and strict follow-up.

MAIN OUTCOME MEASURES

Clinical symptoms and radiological signs.

RESULTS

After craniotomy, the antimicrobial therapy was administered for 8 weeks. Postoperative high resolution TC of the petrous bone showed the presence of material with a soft tissue signal in the right middle ear and dehiscent anterior tegmen tympani. The location of the bony defect in association with the good clinical outcome with medical therapy mitigated against a first choice otosurgical approach to repair the dehiscence. Serial MRI scans provided proof of complete remission and no relapse occurred during a 2-year follow-up.

CONCLUSIONS

Patients with ED can present with chronic otitis media and tegmen tympani defects, predisposing them to serious complications. Imaging is mandatory, and the optimum treatment requires assessment of various factors.

Recurrent Otogenic Intracranial Sepsis: A Key Radiological Finding, Not to Be Missed

Introduction. Otogenic intracranial sepsis is a well-known and established complication of otitis media. It is a major cause of morbidity and mortality from otitis media. We present a case of recurrent otogenic intracranial sepsis and key findings on imaging. Case Report. A 64-year-old male presented with two episodes of severe sepsis secondary to right sided otitis media. During the first episode, he suffered an episode of otogenic pneumococcal sepsis requiring intensive care admission. A year later, he suffered another episode of otogenic intracranial sepsis with evidence of encephalitis, which also required intensive care input. He underwent surgical management of his otitis media with a right myringotomy followed by grommet insertion. Findings. Both computerised tomography and magnetic resonance imaging of the temporal bones demonstrated a defect in the right tegmen tympani, through which a cyst herniated into the epitympanum. Postinfective changes were also noted in the right inferior temporal lobe. Discussion. Tegmen tympani defects are a rare but important risk factor for the spread of intracranial infections from the middle ear. In cases of recurrent otogenic intracranial sepsis, it is crucial to look for evidence of this finding on imaging.

Pneumocephalus in lightning injury with additional neurologic sequelae

Lightning strike injury may present with a variety of injuries including burns and the sequelae of falls following the strike, and any pneumocephalus is usually as a result of a basal skull fracture following a fall. We present a case of pneumocephalus without skull fracture following lightning strike in a 58-year-old male. He suffered bilateral tympanic membrane rupture and the air entered his skull via a congenital defect in petrous tegmen tympani. The patient suffered a range of neurologic symptoms that were not fully resolved six months following injury.

Collagen matrix as an inlay in endoscopic skull base reconstruction

BACKGROUND

Multi-layer reconstruction has become standard in endoscopic skull base surgery. The inlay component used can vary among autografts, allografts, xenografts and synthetics, primarily based on surgeon preference. The short- and long-term outcomes of collagen matrix in skull base reconstruction are described.

METHODS

A case series of patients who underwent endoscopic skull base reconstruction with collagen matrix inlay were assessed. Immediate peri-operative outcomes (cerebrospinal fluid leak, meningitis, ventriculitis, intracranial bleeding, epistaxis, seizures) and delayed complications (delayed healing, meningoencephalocele, prolapse of reconstruction, delayed cerebrospinal fluid leak, ascending meningitis) were examined.

RESULTS

Of 120 patients (51.0 ± 17.5 years, 41.7 per cent female), peri-operative complications totalled 12.7 per cent (cerebrospinal fluid leak, 3.3 per cent; meningitis, 3.3 per cent; other intracranial infections, 2.5 per cent; intracranial bleeding, 1.7 per cent; epistaxis, 1.7 per cent; and seizures, 0 per cent). Delayed complications did not occur in any patients.

CONCLUSION

Collagen matrix is an effective inlay material. It provides robust long-term separation between sinus and cranial cavities, and avoids donor site morbidity, but carries additional cost.

Use of titanium mesh for middle cranial fossa skull base reconstruction

Objectives Temporal bone encephaloceles are usually encountered in the setting of a congenital defect of the tegmen or as an acquired defect after mastoid surgery. A variety of methods have been described in the literature for rigid reconstruction of tegmen defects. We introduce a new method of repair using orbital floor titanium mesh reconstruction plates to reconstruct the floor of the middle cranial fossa, and evaluate the outcomes, complications, and recurrence rates of temporal bone encephaloceles with this technique. Design Retrospective chart review of consecutively treated patients. Setting Tertiary care academic center. Participants Eight patients with middle cranial fossa skull base defects from January 2007 to February 2011. Main Outcome Measures Outcome measures included resolution of cerebrospinal fluid leak (CSF) and development of postoperative infection. Results One of nine patients had a postoperative CSF (cerebrospinal fluid) leak. There were no long-term complications of CSF leak or infection. Conclusions Titanium mesh is a safe and effective substitute for bone grafts in reconstruction of the middle cranial fossa skull base when rigid reconstruction is required.