Cerebral venous sinus thrombosis after vestibular schwannoma surgery: a call for evidence-based management guidelines.

OBJECTIVE Postoperative cerebral venous sinus thrombosis (CVST) is an uncommon complication of posterior fossa surgery. The true incidence of and optimal management strategy for this entity are largely unknown. Herein, the authors report their institutional incidence and management experience of postoperative CVST after vestibular schwannoma surgery. METHODS The authors undertook a retrospective review of all vestibular schwannoma cases that had been treated with microsurgical resection at a single institution from December 2011 to September 2017. Patient and tumor characteristics, risk factors, length of stay, surgical approaches, sinus characteristics, CVST management, complications, and follow-up were analyzed. RESULTS A total of 116 patients underwent resection of vestibular schwannoma. The incidence of postoperative CVST was 6.0% (7 patients). All 7 patients developed lateral CVST ipsilateral to the lesion. Four cases occurred after translabyrinthine approaches, 3 occurred after retrosigmoid approaches, and none occurred following middle cranial fossa approaches. Patients were managed with anticoagulation or antiplatelet therapy. Although patients were generally asymptomatic, one patient experienced intraparenchymal hemorrhage, epidural hemorrhage, and obstructive hydrocephalus, likely as a result of the anticoagulation therapy. However, all 7 patients had a modified Rankin scale score of 1 at the last follow-up. CONCLUSIONS Postoperative CVST is an infrequent complication, with an incidence of 6.0% among 116 patients who had undergone vestibular schwannoma surgery at one institution. Moreover, the management of postoperative CVST with anticoagulation therapy poses a serious dilemma to neurosurgeons. Given the paucity of reports in the literature and the low incidence of CVST, additional studies are needed to better understand the cause of thrombus formation and help to establish evidence-based guidelines for CVST management and prevention.

Middle fossa approach for resection of vestibular schwannoma.

BACKGROUND: Surgical approaches for removal of vestibular schwannoma are done through retrosigmoid, translabyrinthine, or middle fossa approaches, depending on the tumor size, preoperative hearing status, surgical team experience, and patient preference. The middle fossa approach (MFA) for the vestibular schwannoma (VS) route preserves hearing and can be done with minimal morbidity and mortality. METHOD: The authors discuss the surgical anatomy of the middle fossa, internal auditory canal localization techniques, MFA indications and the procedure for VS removal, and outcome. CONCLUSION: Unlike otolaryngologists, who use the MFA to treat various pathological processes that involve the inner or middle ear, many neurosurgeons are unfamiliar with the MFA. Nevertheless, learning the technical nuances of the MFA adds to the neurosurgeon's armamentarium, especially for treatment of small intracanalicular VSs in young patients who wish to preserve hearing.

Transtemporal approach to the removal of a lateral pontine tumor.

This video demonstrates a very useful trajectory to a pontine lesion. A 68-year-old man presented with tongue numbness and weakness. The approach used was a transtemporal presigmoid retrolabyrinthine approach to enable an orthogonal trajectory to the lateral pons. Following the transtemporal opening, the root entry zone of the trigeminal nerve and the root exit zone of the facial nerve are identified. The lateral pons is incised to access the tumor, which upon histological analysis was found to be a metastasis. Excellent visualization of the lateral pons is achieved. The opening, relevant anatomy, and closure are illustrated. The video can be found here: http://youtu.be/vS5fCOY6vp8 .

Surgical approaches for resection of vestibular schwannomas: translabyrinthine, retrosigmoid, and middle fossa approaches.

Surgical removal remains one of the key treatment modalities for vestibular schwannomas. A team approach between a neurotologist and a neurosurgeon offers the patient the expertise of both specialties and maximizes the chances for an optimal outcome. Vestibular schwannomas can typically be resected through 1 of 3 main surgical approaches: the translabyrinthine, the retrosigmoid, or the middle fossa approaches. In this report and videos, the authors describe and illustrate the indications and surgical techniques for the removal of these tumors.

Combined Petrosal Approach for Resection of Petroclival Meningioma: 2-Dimensional Operative Video.

Petroclival meningiomas are rare skull base lesions, which originate at the upper two thirds of the clivus, medially to cranial nerves V-XI. Interposition of the cranial nerves between the tumor and surgeon and the proximity/involvement of the basilar artery and brainstem make surgical treatment challenging. Nevertheless, documented growth, brainstem compression, and neurologic symptoms argue in favor of resection. Depending on the size of the lesion, its medial origin along the clivus, extension into the middle fossa, and preoperative hearing, different approaches have been described. A 44-year-old male had a large petroclival meningioma with brainstem compression, which was diagnosed during work-up for stroke. On examination he only had facial numbness in the V2 distribution, but normal hearing and facial function. Due to the size of the lesion, extensive dural attachment along the petroclival junction, a significant middle fossa component, and preserved hearing, a combined petrosal approach using presigmoid, retrolabyrinthine, and subtemporal exposures was chosen. The chosen approach provides a wide exposure with multiple degrees of freedom in both the petroclival region and middle fossa. Furthermore, it allows for hearing preservation without limiting surgical exposure. Gross total resection (Simpson grade II) was achieved. Intraoperatively, the fourth cranial nerve was transected and treated with primary end-to-end neurorrhaphy. The patient had a good neurologic outcome, with a trochlear nerve deficit, which partially improved over 12 months.

Factors associated with hearing outcomes after a middle fossa approach in 131 consecutive patients with vestibular schwannomas.

OBJECTIVE: The middle fossa approach is an effective option for the treatment of small (Koos grade I and II) vestibular schwannomas (VSs) when the goal is hearing preservation. The authors evaluated the rates of hearing preservation and examined the factors associated with improved hearing outcomes after the middle fossa approach for VSs. METHODS: In this retrospective, single-center cohort study evaluating the clinical outcomes after resection of small VSs using the middle fossa approach, consecutive adult patients (> 18 years) who underwent surgery between January 2000 and December 2021 were included. Clinical and imaging characteristics were analyzed, including baseline hearing status, duration of surgery, anesthetic parameters, and imaging characteristics of the surgically treated tumors. RESULTS: Among the 131 included patients, 102 had valid and discoverable pre- and postoperative audiology assessments. The mean follow-up was 26 months (range 1-180 months). There were 85 patients with serviceable hearing preoperatively, defined as American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) class A or B, of whom 78% retained class A or B hearing at the last follow-up. Binary logistic regression demonstrated that preoperative hearing AAO-HNS class (OR 0.19, 95% CI 0.05-0.77; p = 0.02), overlap between fundus and cochlea (OR 0.32, 95% CI 0.11-0.96; p = 0.04), and duration of anesthesia (OR 0.98, 95% CI 0.97-0.99; p = 0.03) were independent predictors of hearing outcomes. Additionally, 75% of patients with high diffusion-weighted imaging signal in the tumor (p = 0.009) and 67% of patients with the tumor originating at the modiolus of the cochlea (p = 0.004) had poor hearing outcomes. CONCLUSIONS: The hearing preservation rates after microsurgical resection of small VSs using the middle fossa approach are high, with 78% of patients maintaining AAO-HNS class A or B hearing. Poor hearing status at baseline, longer duration of anesthesia, and large overlap between the fundus of the internal auditory canal and the cochlea were independently associated with unfavorable hearing outcomes. Imaging characteristics can be used to stratify patients' risk of hearing loss.

The Medially-Invasive Cholesteatoma: An Aggressive Subtype of a Common Pathology.

OBJECTIVE: Describe the outcomes of treatment for patients with cholesteatomas that are medially invasive to the otic capsule, petrous apex, and/or skull base. STUDY DESIGN: Retrospective case series. SETTING: Two tertiary care academic centers. PATIENTS: Patients surgically managed for medially-invasive cholesteatoma at two tertiary care institutions from 2001 to 2017. INTERVENTIONS: Surgical management of medially-invasive cholesteatomas. MAIN OUTCOME MEASURES: The presenting symptoms, imaging, pre- and post-operative clinical course, and complications were reviewed. RESULTS: Seven patients were identified. All patients had pre-operative radiographic evidence of invasive cholesteatoma with erosion into the otic capsule beyond just a lateral semicircular canal fistula. Five patients had a complex otologic history with multiple surgeries for recurrent cholesteatoma including three with prior canal wall down mastoidectomy surgeries. Average age at the time of surgery was 41.3 years (range 20-83). Two patients underwent a hearing preservation approach to the skull base while all others underwent a surgical approach based on the extent of the lesion. Facial nerve function was maintained at the pre-operative level in all but one patient. No patient developed cholesteatoma recurrence. CONCLUSIONS: The medially-invasive cholesteatoma demonstrates an aggressive, endophytic growth pattern, invading into the otic capsule or through the perilabyrinthine air cells to the petrous apex. Surgical resection remains the best treatment option for medially-invasive cholesteatoma. When CSF leak is a concern, a subtotal petrosectomy with closure of the ear is often necessary.

Are Opioids Necessary in Middle Ear Surgery? Comparing the Transcanal and Postauricular Approach.

OBJECTIVE: Understand opioid-prescribing patterns in otologic surgery and the difference in opioid use between transcanal and postauricular surgery. STUDY DESIGN: Prospective survey. SETTING: Multihospital network. PATIENTS: All patients undergoing otologic surgery from March 2017 to January 2019. INTERVENTION: Patients undergoing otologic surgery were surveyed regarding postoperative opioid use and their level of pain control. Patients were divided by surgical approach (transcanal vs. postauricular). Those who underwent mastoid drilling were excluded. Narcotic amounts were converted to milligram morphine equivalents (MME) for analysis. MAIN OUTCOME MEASURES: Amount of opioid was calculated and compared between the two groups. Mann-Whitney U test and Chi-square testing were used for analysis. RESULTS: Fifty-five patients were included in the analysis; of these 18 (33%) had a postauricular incision. There was no difference in age (p = 0.85) or gender (p = 0.5) between the two groups. The mean amount of opioid prescribed (MME) in the postauricular and transcanal groups was 206.4 and 143 (p = 0.038) while the mean amount used was 37.7 and 37.5 (p = 0.29) respectively. There was no difference in percentage of opioid used (p = 0.44) or in patient-reported level of pain control (p = 0.49) between the two groups. CONCLUSION: Patients in both the transcanal and postauricular groups used only a small portion of their prescribed opioid. There was no difference in the amount of opioid used or the patient's reported level of pain control based on the approach. Otologic surgeons should be aware of these factors to reduce narcotic diversion after ear surgery.

Internal Auditory Canal Lipoma: An Unusual Intracranial Lesion.

BACKGROUND: Internal auditory canal (IAC) lipomas are rare intracranial lesions. Consequently, preoperative imaging is essential in differentiating IAC lipomas from more common tumors such as vestibular schwannomas. The hallmark of lipomas on magnetic resonance imaging (MRI) is hyperintensity on T1-weighted images that suppresses on fat-suppressed sequences and does not enhance with gadolinium administration. CASE DESCRIPTION: The present case describes a 53-year-old woman who was misdiagnosed with a vestibular schwannoma because of the lack of appropriate MRI sequences. CONCLUSIONS: This case demonstrates the importance of ensuring that both fat-suppressed and non-fat-suppressed T1-weighted pregadolinium images are obtained in the diagnostic process of IAC lesions. It is therefore recommended that imaging centers ensure that such sequences are included in their MRI protocols.

Internal Auditory Canal Variability: Anatomic Variation Affects Cisternal Facial Nerve Visualization.

BACKGROUND: The internal auditory canal (IAC) is an important landmark during surgery for lesions of the cerebellopontine angle. There is significant variability in the position and orientation of the IAC radiographically, and the authors have noted differences in surgical exposure depending on the individual anatomy of the IAC. OBJECTIVE: To test the hypothesis that IAC position and orientation affects the surgical exposure of the IAC and facial nerve, especially when performing the translabyrinthine approach. METHODS: The authors retrospectively reviewed magnetic resonance imaging studies of 50 randomly selected patients with pathologically confirmed vestibular schwannomas. Measurements, including the anterior (APD) and posterior (PPD) petrous distances, the anterior (APA) and posterior (PPA) petro-auditory angles, and the internal auditory angle (IAA), were obtained to quantify the position and orientation of the IAC within the petrous temporal bone. RESULTS: The results quantitatively demonstrate tremendous variability of the position and orientation of the IAC in the petrous temporal bone. The measurement ranges were APD 10.2 to 26.1 mm, PPD 15.1 to 37.2 mm, APA 104 to 157°, PPA 30 to 96°, and IAA -5 to 40°. CONCLUSION: IAC variability can have a substantial effect on the surgical exposure of the IAC and facial and vestibulocochlear nerves. Specifically, a horizontally oriented IAC with a small IAA may have significant impact on visualization of the facial nerve within its cisternal segment with the translabyrinthine approach. The retrosigmoid approach is less affected with IAC variability in position and angle.

Increasing Frailty, Not Increasing Age, Results in Increased Length of Stay Following Vestibular Schwannoma Surgery.

OBJECTIVE: Understand the frailty of vestibular schwannoma surgical patients and how frailty impacts clinical course. STUDY DESIGN: Retrospective Cohort. SETTING: Single-tertiary academic hospital. PATIENTS: All patients undergoing vestibular schwannoma surgery. INTERVENTION: The modified frailty index (mFI) was calculated for all patients undergoing surgery for vestibular schwannoma between 2011 and 2018. Patient demographics and medical history, perioperative course, and postoperative complications were obtained from the medical record. MAIN OUTCOME MEASURES: The primary endpoint was hospital length of stay (LOS). Secondary endpoint was postoperative complications. Basic statistical analysis was performed including multivariate linear regressions to determine independent predictors of LOS. RESULTS: There were 218 patients included and the mean age was 48.1 ±â€Š0.9 (range 12-77). One-hundred ten patients were male (50.5%). The mean ICU LOS was 1.6 ±â€Š0.1 days while mean total hospital LOS was 4.3 ±â€Š0.2. There were 145 patients (66.5%) who were robust (nonfrail) with an mFI of 0, while 73 (33.5%) had an mFI of ≥1. Frailty (mFI≥2) was associated with longer hospital LOS compared with the prefrail (p = 0.0014) and robust (p = 0.0004) groups, but was not associated with increased complications (OR = 1.3; 95% CI: 0.5-3.7; p = 0.5925) or ICU LOS (p > 0.05). In multivariate analysis, increased mFI, and NOT increased age, was an independent risk factor for increased hospital LOS (p = 0.027). CONCLUSION: Increasing frailty, and not increasing age, is an independent risk factor for longer hospital LOS, but not for increased postoperative complications. Patients' frailty status may be useful preoperatively in counselling patients about postoperative expectations and frail vestibular schwannoma patients may require increased health spending costs given their increased hospital LOS.

Primary Petrous Apex Epidermoids With Skull Base Erosion.

OBJECTIVE: To describe the clinical course and treatment outcomes for patients with petrous apex epidermoid with skull base erosion. STUDY DESIGN: Retrospective case series. SETTING: Tertiary-care academic center. PATIENTS: Patients surgically managed for petrous apex epidermoids at a single-tertiary care institution from 2001 to 2017. INTERVENTIONS: Surgical management of primary petrous apex epidermoids. MAIN OUTCOME MEASURES: The presenting symptoms, imaging, pre- and postoperative clinical course, and complications were reviewed. RESULTS: Seven patients were identified. The most common presenting symptoms included: sudden sensorineural hearing loss (n = 3), headaches (n = 1), vertigo (n = 2), and facial paralysis/paresis (n = 2). An epidermoid was discovered in two patients as an incidental finding after a head trauma and one patient after admission for altered mental status and meningitis. Two patients presented with complete facial paralysis (House-Brackmann 6/6). Preoperative normal hearing (pure-tone average < 25 db) was identified in three patients and serviceable hearing (pure-tone average 25-60 dB) in one patient. Three patients with nonserviceable hearing underwent a transcochlear or transotic approach. The remaining four patients underwent an attempted hearing preservation approach. Postoperatively, one patient developed delayed facial paralysis, improving within 3 months. Hearing was preserved in three patients. Two patients developed recurrence of disease within 4 and 7 years respectively. CONCLUSIONS: Surgical management of aggressive petrous apex epidermoid is effective to preserve facial function and prevent recurrence. In our series different surgical approaches were used with variable outcomes.

Variations in Stapes Surgery Cost within a Multihospital Network.

OBJECTIVE: To identify costs and operative times for stapedotomy and evaluate factors influencing cost variation. STUDY DESIGN: Case series with cost analysis. SETTING: Multihospital network. SUBJECTS AND METHODS: A multihospital network's standardized activity-based accounting system was used to determine costs and operative times of all patients undergoing stapedotomy from 2013 to 2017. Subjects with additional procedures were excluded. Correlations between variable factors and cost were calculated by Spearman correlation coefficients. Audiometric and cost data were compared with a Mann-Whitney U test. RESULTS: The study cohort included 176 stapedotomies performed by 23 surgeons at 10 hospitals. Mean ± SD patient age was 44.3 ± 17.4 years. Mean cut-to-close time was 61.1 ± 23.55 minutes. Mean total encounter cost was $3542.14 ± $1258.78 (US dollars). Significant factors correlating with increased total encounter cost were surgical supply cost (r = 0.74, P < .0001) and cut-to-close time (r = 0.66, P < .0001). Laser utilization ($563.37 ± $407.41) was the highest-cost surgical supply, with the carbon dioxide laser being significantly more costly than the potassium titanyl phosphate (KTP; $852.60 vs $230.55, P < .001). Additionally, the carbon dioxide laser was associated with a significantly higher mean total encounter cost than the KTP laser ($4645.43 vs $2903.00, P < .001) and cases where no laser was used ($4645.43 vs $2932.47, P < .001). There was no difference in mean total encounter cost between the KTP laser and cases of no laser use ($2903.00 vs $2932.47, P = .75). CONCLUSIONS: Significant cost variation exists in stapes surgery. Surgical supply cost, specifically laser use, may be associated with significantly increased costs. Reducing variation in costs while maintaining outcomes may improve health care value.

Reduced Purposeful Head Movements During Community Ambulation Following Unilateral Vestibular Loss.

BACKGROUND: Individuals with unilateral vestibular hypofunction (UVH) alter their movement and reduce mobility to try to stabilize their gaze and avoid symptoms of dizziness and vertigo. OBJECTIVE: To determine if individuals with UVH 6 weeks after surgery demonstrate altered head and trunk kinematics during community ambulation. METHODS: A total of 15 vestibular schwannoma patients with documented postoperative unilateral vestibular loss and 9 healthy controls with symmetrical vestibulo-ocular reflexes participated in this cross-sectional study. Head kinematics (head turn frequency, amplitude, and velocity) and head-trunk coordination during community ambulation were obtained from inertial measurement units for all head movements and within specific amplitudes of head movement. RESULTS: Individuals with UVH made smaller (mean 26° [SD = 3°] vs 32° [SD = 6°]), fewer (mean 133 [SD = 59] vs 221 [SD = 64]), and slower (mean 75°/s [SD = 8°/s] vs 103°/s [SD = 23°/s]) head turns than healthy individuals ( P < .05) but did not demonstrate significantly increased head-trunk coupling (mean 38% [SD = 18%] vs 31% [SD = 11%], P = .22). When small (≤45°) and large (>45°) head turns were considered separately, individuals with UVH demonstrated increased head-trunk coupling compared with healthy individuals for large head turns (mean 54% [SD = 23%] vs 33% [SD = 10%], P = .005). CONCLUSIONS: This study demonstrated that although walking at an adequate speed, individuals with UVH made fewer, smaller, and slower head movements symmetrically in both directions compared with healthy individuals and did not decouple their head movement relative to their trunk when required to make larger purposeful head turns during community ambulation.

What Is the Safety and Efficacy of Chemical Venous Thromboembolism Prophylaxis Following Vestibular Schwannoma Surgery?

OBJECTIVE: The benefit of routine chemical prophylaxis use for venous thromboembolism (VTE) prevention in skull base surgery is controversial. Chemical prophylaxis can prevent undue morbidity and mortality, however there are risks for hemorrhagic complications. STUDY DESIGN: Retrospective case-control. METHODS: A retrospective chart review of patients who underwent surgery for vestibular schwannoma from 2011 to 2016 was performed. Patients were divided by receipt of chemical VTE prophylaxis. Number of VTEs and hemorrhagic complications (intracranial hemorrhage, abdominal hematoma, and postauricular hematoma) were recorded. RESULTS: One hundred twenty-six patients were identified, 55 received chemical prophylaxis, and 71 did not. All the patients received mechanical prophylaxis. Two patients developed a deep vein thrombosis (DVT) and one patient developed a pulmonary embolism (PE). All patients who developed a DVT or PE received chemical prophylaxis. There was no difference in DVT (p = 0.1886) or PE (p = 0.4365) between those who received chemical prophylaxis and those who did not. Five patients developed a hemorrhagic complication, two intracranial hemorrhage, three abdominal hematoma, and zero postauricular hematoma. All five patients with a complication received chemical prophylaxis (p = 0.00142). The relative risk of a hemorrhagic complication was 14.14 (95% CI = 0.7987-250.4307; p = 0.0778). CONCLUSION: There was a significant difference between the number of hemorrhagic complications but not between numbers of DVT or PE. Mechanical and chemical prophylaxis may lower the risk of VTE but in our series, hemorrhagic complications were observed. These measures should be used selectively in conjunction with early ambulation.

Variation in Tympanoplasty Cost in a Multihospital Network.

OBJECTIVES: Identify costs and operative times for tympanoplasty, and evaluate factors influencing cost and time variation. STUDY DESIGN: Retrospective cohort study. SETTING: Multihospital network. PATIENTS: Patients undergoing tympanoplasty from 2008 to 2016. Subjects with additional procedures were excluded. INTERVENTIONS: A multihospital network's standardized activity-based accounting system was used to determine costs and operative times of tympanoplasty. MAIN OUTCOME MEASURES: Correlation between variable factors and cost was calculated by Spearman correlation coefficients. Statistical comparisons of cost and time were made between surgeons and hospitals using an ANOVA test (Kruskal-Wallis) followed by Dunn's test to correct for multiple comparisons. All providers or hospitals with single cases were excluded for statistical comparison. RESULTS: The study cohort included 487 tympanoplasties performed by 44 surgeons at 13 hospitals. Mean patient age was 18.2 ±â€Š17.4 years. Mean cut-to-close time was 85.8 ±â€Š56.7 minutes. Mean total encounter cost was $3491 ±â€Š$1,627. Substantial factors associated with total encounter cost were anesthesia cost (r = 0.8782; 95% CI 0.852-0.900, p < 0.001) and cut-to-close time (r = 0.7543; 95% CI 0.707-0.7949, p < 0.001). The total itemized supply cost was less correlated with total encounter cost (r = 0.3176; 95% CI 0.2128-0.4151, p < 0.001). Laser utilization (mean cost $541 ±â€Š$343) and artificial graft material (mean cost $199 ±â€Š$94) were the major supply costs. CONCLUSION: Significant variation in tympanoplasty costs exists among different surgeons and hospitals within a multihospital network. Reducing variation in costs while maintaining outcomes may improve healthcare value and eliminate waste.

Multifocal cavernous hemangioma of the jugular foramen: a rare skull base vascular malformation.

Jugular foramen cavernous hemangiomas are extremely rare vascular malformations, and, to the best of the authors' knowledge, their occurrence as multifocal lesions involving both intra- and extracranial compartments has never been reported before. Here, the authors describe the case of a 60-year-old woman with a complex multifocal jugular foramen cavernous hemangioma. The patient presented with signs and symptoms concerning for jugular foramen syndrome, as well as a right neck mass. Surgical extirpation of the lesion was achieved by a multidisciplinary team via a right infratemporal fossa approach (Fisch type A) with concurrent high neck dissection and a closure buttressed with an autologous fat graft and a temporoparietal fascial flap. Although rare, cavernous hemangiomas should be included in the differential diagnosis of jugular foramen masses.

Transient facial nerve palsy after topical papaverine application during vestibular schwannoma surgery. Case report.

Some evidence in the literature supports the topical application of papaverine to the cochlear nerve to prevent internal auditory artery vasospasm and cochlear ischemia as a method of enhancing the ability to preserve hearing during acoustic neuroma surgery. The authors report a case of transient facial nerve palsy that occurred after papaverine was topically applied during a hearing preservation acoustic neuroma removal. A 58-year-old woman presented with tinnitus and serviceable sensorineural hearing loss in her right ear (speech reception threshold 15 dB, speech discrimination score 100%). Magnetic resonance imaging demonstrated a 1.5-cm acoustic neuroma in the right cerebellopontine angle (CPA). A retrosigmoid approach was performed to achieve gross-total resection of the tumor. During tumor removal, a solution of 3% papaverine soaked in a Gelfoam pledget was placed over the cochlear nerve. Shortly thereafter, the quality of the facial nerve stimulation deteriorated markedly. Electrical stimulation of the facial nerve did not elicit a response at the level of the brainstem but was observed to elicit a robust response more peripherally. There were no changes in auditory brainstem responses. Immediately after surgery, the patient had a House-Brackmann Grade V facial palsy on the right side. After several hours, this improved to a Grade I. At the 1-month follow-up examination, the patient exhibited normal facial nerve function and stable hearing. Intracisternal papaverine may cause a transient facial nerve palsy by producing a temporary conduction block of the facial nerve. This adverse effect should be recognized when topical papaverine is used during CPA surgery.

The surgical learning curve in aural atresia surgery.

OBJECTIVE: The objective of this retrospective case review is to examine the effect of surgical learning on hearing outcomes and complications in congenital aural atresia surgery. PATIENTS: Sixty-four consecutive ears (in 60 patients) operated on during the period of 1994 to 2004 at a tertiary referral center were studied. INTERVENTION(S): Intervention consisted of aural atresiaplasty through an anterior approach by the same surgeon (C.S.). MAIN OUTCOME MEASURE(S): Hearing outcomes and complication rates were compared between four temporally sequential groups of 16 ears. Acceptable hearing and complication rate outcomes were defined as results comparable to larger series in the literature. RESULTS: Hearing results, in the short term, comparable to larger series were achieved during the first group of ears (nos. 1-16). A plateau in the learning curve for short-term hearing outcomes was achieved after the first two groups, that is, after 32 ears. Hearing outcomes, in the long term (>1 year) comparable to larger series, were achieved in the second group of ears (nos. 16-32). The learning curve for long-term hearing demonstrated a significant improvement in outcomes in the final group of 16 ears compared with the first 48 ears. Long-term hearing results for the final group show closure of the postoperative air-bone gap to less than 30 dB in 94% of cases. Postoperative complication rates were equivalent to larger series in the first group of 16 ears and showed no statistically significant difference between the four groups. There was one patient with sensorineural hearing loss after surgery; there were no anacoustic ears and no facial palsies in the study group. CONCLUSIONS: A learning curve of at least 32 ears was required to achieve stable short-term hearing results. To achieve stable long-term hearing results required a learning curve of at least 48 patients in our series. Complication rates remained stable throughout the study period.

Eliminating the limitations of manual crimping in stapes surgery: mid-term results of 90 patients in the Nitinol stapes piston multicenter trial.

OBJECTIVE: To present our mid-term results of our multicenter study using the Nitinol self-crimping stapes piston, focusing on the interindividual variations of postoperative air-bone gap closures (ABGC), postoperative hearing results, and postoperative recurrences of conductive hearing loss and to compare these findings with our pilot group of patients. STUDY DESIGN: Prospective, multicenter cohort study involving three academic tertiary care referral centers from Australia, Switzerland, and the United States. METHODS: Ninety patients with otosclerosis undergoing laser-stapedotomy with the Nitinol stapes piston were matched to reference patients from our titanium piston database. The effects of the self-crimping Nitinol piston on the postoperative ABGC, the postoperative interindividual air-bone gap (ABG) variations, and the postoperative hearing results were investigated 3, 6, 12, 18, and 24 months postoperatively. These data were statistically compared with the results of the control patients in our titanium stapes piston database and the results of our previously published pilot study. RESULTS: The mean postoperative ABG and the interindividual variations of the postoperative ABG continue to be significantly smaller in the Nitinol group; the extent of ABGC now is significantly larger in the Nitinol piston group. The postoperative mid-term stability of ABGC was similar in both groups. No adverse reactions occurred during follow-up. CONCLUSION: Our mid-term results continue to show that the self-crimping shape memory alloy Nitinol stapes piston overcomes the limitations of manual malcrimping in stapedotomy, thus simplifying and optimizing the surgical procedure. This so far has allowed reliable, safe, and consistent ABGC in patients with otosclerosis.