Management of intralabyrinthine schwannomas

OBJECTIVES

Our protocol to manage the intralabyrinthine schwannoma (ILS).

METHODS

Retrospective chart review of 7 consecutive patients managed for ILS.

RESULTS

Five patients underwent surgical removal of the lesions and none experienced significant complications or recurrent disease. One patient refused surgical treatment and was closely followed by serial MRI scans with no signs of tumor growth. One patient is presently managed conservatively due to a good hearing.

CONCLUSIONS

Diagnosis of ILS is based on high resolution MRI scans and should be included in the differential diagnosis of patients investigated for cochleovestibular symptoms. Treatment modality of ILS is controversial and depends patients' age, severity of vertigo and hearing loss. In the authors' experience surgery is indicated in all cases with invalidating vertigo and in the young patients with severe hearing loss. Conservative strategy is advised in older patients and in cases with preserved good hearing and no invalidating vertigo. These patients must be followed up using high resolution MRI because of the risk of tumor growth into the internal auditory canal. While tumors with exclusive involvement of the inner ear may be removed by means of a completely extradural approach, tumor growth with involvement of the internal auditory canal dictates the necessity of opening the dura exposing the patients to the potential risks associated with the procedure.

Posterior petrous face meningiomas: an algorithm for surgical management

OBJECTIVE

The objective of the present study was to report our surgical strategy in the management of 81 patients with posterior petrous face meningiomas.

STUDY DESIGN

Retrospective study.

SETTING

This study was conducted at a quaternary private otology and cranial base center.

PATIENTS

Of 139 patients with posterior fossa meningioma, 81 occurred on the posterior petrous face of the temporal bone and were the object of this study.

INTERVENTIONS

Thirty-one patients were approached by the enlarged translabyrinthine approach. The enlarged translabyrinthine approach with transapical extension Type II was performedin 29 patients. The combined retrosigmoid-retrolabyrinthine approach was chosen in 8 cases. The modified transcochlear approach Type A with permanent posterior transposition of the facial nerve (FN) was performed in 6 patients. Two patients underwent a retrolabyrinthine subtemporal transapical approach. One patient underwent a transpetrous middle cranial fossa approach. Four patients with intracanalicular meningiomas were operated on through the enlarged middle cranial fossa approach.

RESULTS

Total removal of the tumor (Simpson Grades I and II) was achieved in most patients (92.5%). The FN was anatomically preserved in 79 of the 81 (97.5%) patients. Five patients had less than 1 year follow-up, and 2 patients were lost to follow-up and were excluded in evaluation of the final FN outcome. At 1-year follow-up, 46 patients (63%) had Grade I to II, 19 (26%) had Grade III, 4 (5.4%) had Grade IV, 1 (1.3%) had Grade V, and 3 (4.1%) had Grade VI. Hearing-preserving surgery was attempted in 15 patients (18.5%) with preoperative serviceable hearing. Of these 15 patients, 11 had their hearing preserved at the same preoperative level, and 4 experienced postoperative deafness. Postoperatively, a new deficit of 1 or more of the lower cranial nerves was recorded in 3 patients. One patient experienced subcutaneous cerebrospinal fluid collection that required surgical management.

CONCLUSION

Total tumor removal (Simpson Grades I-II) remains our treatment of choice and takes priority over hearing preservation. Subtotal resection is indicated for older and debilitated patients with giant lesions to relieve the tumor compression on the cerebellum and brainstem. Subtotal removal is also preferred in the face of the absence of a plane of cleavage between the tumor and the brainstem, in the presence of encasement of vital neurovascular structures, in elderly patients with tumors adherent to preoperatively normal facial or lower cranial nerves.

Surgical Management of Jugular Foramen Meningiomas: A Series of 13 Cases and Review of the Literature

OBJECTIVE

Primary meningiomas occurring within the jugular foramen are exceedingly rare lesions presumed to originate from arachnoid-lining cells situated within the jugular foramen. The objective of this study is to analyze the management and outcome in a series of 13 primary jugular foramen meningiomas collected at a single center.

STUDY DESIGN

Retrospective study.

SETTING

Quaternary referral otology and skull base private center.

METHODS

Charts belonging to 13 consecutive patients with pathologically confirmed jugular foramen meningioma surgically treated between September 1991 and May 2005 were examined retrospectively. The follow-up of the series ranged from 12 to 120 (mean, 42.8 +/- 27.5) months.

RESULTS

Four (28.5%) patients underwent single-stage tumor removal through the petro-occipital transigmoid (POTS) approach. In two patients with preoperative unserviceable hearing, a combined POTS-translabyrinthine approach was adopted. Two patients underwent a combined POTS-transotic approach because of massive erosion of the carotid canal. A modified transcochlear approach type D with posterior rerouting of the facial nerve and transection of the sigmoid sinus and jugular bulb was performed in two patients with a huge cerebellopontine angle tumor component with extension to the prepontine cistern together with massive involvement of the petrous bone and middle ear and encasement of the vertical and horizontal segments of the intrapetrous carotid artery. In one patient with evidence of a dominant sinus on the site of the tumor, a subtotal tumor removal via an enlarged translabyrinthine approach (ETLA) was planned to resect the intradural component of the tumor. Two patients in our series underwent a planned staged procedure on account of a huge tumor component in the neck. One of these patients underwent a first-stage infratemporal fossa approach type A to remove the tumor component in the neck; the second-stage intradural removal of the tumor was accomplished via an ETLA. The last patient underwent a first-stage modified transcochlear type D approach to remove the intradural tumor component followed by a second-stage transcervical procedure for removal of the extracranial component. Gross total tumor removal (Simpson grade I-II) was achieved in 11 (84.6%) cases. Subtotal removal of the tumor was accomplished in two patients. Good facial nerve function (grades I and II) was achieved in 46.1% of cases, whereas acceptable function (grade III) was achieved in the remaining cases 1 year after tumor removal. Hearing was preserved at the preoperative level in all four patients who underwent surgery via the POTS approach. After surgery, no patient recovered function of the preoperatively paralyzed lower cranial nerves. A new deficit of one or more of the lower cranial nerves was recorded in 61.5% of cases.

CONCLUSIONS

Surgical resection is the treatment of choice for jugular foramen meningiomas. Among the various surgical techniques proposed for dealing with these lesions, we prefer the POTS approach alone or combined with the translabyrinthine or transotic approaches. Despite the advances in skull base surgery, new postoperative lower cranial nerve deficits still represent a challenge.

Intraoperative Cochlear Nerve Monitoring in Vestibular Schwannoma Surgery – Does It Really Affect Hearing Outcome?

OBJECTIVE

The objective of this study was to examine the usefulness of intraoperative cochlear nerve monitoring (ICNM) in the preservation of normal and social hearing in vestibular schwannoma (VS) removal.

METHODS

A retrospective chart review was conducted. Of 1315 patients operated for VS between June 1988 and December 2005, 150 patients were subjected to hearing preservation surgery. Among these, 99 patients with preoperative normal and social hearing (class A and B in the modified Sanna classification) and with a small tumor <1.5 cm in size were included in the analysis. The difference in hearing preservation rates between patients operated with and without ICNM was statistically examined using Fisher's exact test. An initial analysis was conducted for the total group. Patients were then divided into two subgroups according to the surgical approach (middle cranial fossa and retrosigmoid-retrolabyrinthine). The effectiveness of ICNM in each subgroup was analyzed.

RESULTS

The hearing preservation rate was 26.7% in cases operated with ICNM and 20.8% in cases without ICNM. The difference did not reach statistical significance (p = 0.79). In subgroup analyses, the ICNM did not prove to contribute to the significantly higher hearing preservation rate.

CONCLUSIONS

ICNM did not increase the ratio of patients with postoperative normal and social hearing in VS surgery.

Decision Making for Solitary Vestibular Schwannoma and Contralateral Meniere’s Disease

The existence of dual inner ear pathology such as unilateral Meniere's disease (MD) with a contralateral vestibular schwannoma (VS) is very rare, but provides the otologist with a significant management dilemma. In this study, we present 5 cases of unilateral disabling MD with a contralateral VS in the better hearing ear. Conservative management of the VS is mandated unless there are impending complications, with management directed toward controlling the vertigo attributed to MD. If and when the VS requires intervention, or the hearing in that ear deteriorates to unserviceable levels, cochlear implant of the ear affected by MD prior to addressing the VS provides optimal management.

Intratympanic gentamicin: a 1-day protocol treatment for unilateral Meniere's disease

PURPOSE

The objective of this study was to assess the usefulness of low-dose intratympanic gentamicin administration in patients with Meniere's disease (MD).

MATERIALS AND METHODS

We carried out a retrospective review of the charts of 55 patients with definite MD in accordance with the AAO-HNS (American Academy of Otolaryngology-Head and Neck Surgery) Diagnostic Scale who were treated at Gruppo Otologico (Piacenza, Rome, Italy). The treatment protocol consisted of 3 intratympanic injections of gentamicin at a 12-hour interval between each administration.

RESULTS

Results were resumed in accordance with AAO-HNS criteria and showed complete control of vertigo spells in 60% (class A), good control in 16% (class B), moderate control in 4% (class C), poor control in 16% (class D), and no control in 4% (class E) of the patients. Audiological assessment showed unchanged thresholds in 61%, improvement in 22%, and worsening in 17% of the cases.

CONCLUSION

Administration of gentamicin is a good alternative to medical and surgical procedures in the treatment of intractable MD. One-day treatment allows for adequate control of vertigo attacks without compromising hearing and quality of life and with reduced costs.

Absence of the Contralateral Internal Carotid Artery: A Challenge for Management of Ipsilateral Glomus Jugulare and Glomus Vagale Tumors

OBJECTIVE

Extensive involvement of the internal carotid artery (ICA) by jugular and vagal paragangliomas represents a challenging problem for skull-base surgeons: radical tumor resection and preservation of the vessel often cannot be achieved in these cases. The aim of this article was to report the management of a complex case of right ipsilateral jugular and vagal paragangliomas in a patient with absence of the contralateral ICA due to a previous removal of a left carotid body tumor. Surgical removal of the lesions was performed after stenting of the cervical and intratemporal segment of the ICA.

METHODS

The charts and all the examinations of the patient were retrospectively reviewed. The patient, a 40-year-old man, was treated at the Gruppo Otologico, a private quaternary referral center for neurotology and skull-base surgery.

RESULTS

The tumors were completely resected during surgery and manipulation of the ICA was greatly facilitated by the stent. No complication occurred during or immediately after surgery; after a follow-up period of 24 months there was no sign of recurrence and imaging studies demonstrated patency of the stented vessel.

CONCLUSION

This report suggests that placement of endovascular stents in the cervical and temporal segments of the ICA has the potential of changing the whole therapeutic management in cases of temporal and vagal paragangliomas that surround and invade the vessel, especially in those cases in which permanent balloon occlusion of the ICA is not feasible.

Intracanalicular Meningioma

OBJECTIVE

Intracanalicular meningiomas are extremely rare, and only 36 cases have been reported to date. The aim of this study is to describe the clinical, radiologic, and histopathologic features of 13 intracanalicular meningiomas highlighting important aspects of tumor diagnosis and treatment.

STUDY DESIGN

Retrospective study.

SETTING

Quaternary referral otology and cranial base private center.

PATIENTS

Thirteen consecutive patients with pathologically confirmed intracanalicular meningioma surgically treated between December 1988 and July 2006. The follow-up of the series ranged from 13 to 60 months.

INTERVENTIONS

Nine patients with unserviceable hearing were operated on through the translabyrinthine approach. Four patients underwent enlarged middle cranial fossa approach with the intention of preserving their hearing.

RESULTS

Total tumor removal was achieved in all cases. The postoperative facial nerve function was either excellent or good (House-Brackmann Grade I or II) in 10 cases (77%) and acceptable (Grade III) in one case. Two patients with preoperative facial paresis showed no improvement in their facial nerve function. In patients who underwent surgery via the enlarged middle cranial fossa, hearing was preserved at the preoperative level in two cases, but serviceable hearing was lost in the remaining two.

CONCLUSION

Primary meningiomas of the internal auditory canal are extremely rare. On account of a lack of specific symptoms and the limited diagnostic findings, preoperative diagnosis of intracanalicular meningioma still represents a diagnostic challenge. Intraoperative findings may help in differentiating meningiomas from other intracanalicular lesions.

Surgical Management of Jugular Foramen Schwannomas With Hearing and Facial Nerve Function Preservation: A Series of 23 Cases and Review of the Literature

OBJECTIVE

Schwannomas of the jugular foramen are rare lesions and controversy regarding their management still exists. The objective of this retrospective study was to analyze the management and outcome in a series of 23 cases collected at a single center.

SETTING

This study was conducted at a quaternary private otology and skull base center.

METHODS

Charts belonging to patients with a diagnosis of jugular foramen schwannoma attending our center between May 1988 and April 2006 were examined retrospectively.

RESULTS

The study group consisted of 23 patients. One patient (a 73-year-old woman) with normal lower cranial nerves function was managed with watchful expectancy and regular clinical and radiologic follow ups. The infratemporal fossa approach-type A (IFTA-A) was performed in 3 cases. One patient underwent a transcochlear-transjugular approach. Of the 22 patients surgically treated, 12 patients were operated on by the petrooccipital transsigmoid approach (POTS). In one patient with a preoperative dead ear, a combined POTS-translabyrinthine approach was adopted. Two patients were operated on through the POTS approach combined with the transotic approach. In another case (a 67-year-old woman), a subtotal tumor removal through a transcervical approach was planned to resect a 10-cm mass in the neck. One patient underwent a first-stage combined transcervical-subtotal petrosectomy approach to remove a huge tumor in the neck; the second-stage intradural removal of the tumor was accomplished through a translabyrinthine-transsigmoid-transjugular approach. The last patient underwent a first-stage combined transcervical-subtotal petrosectomy approach to remove the neck tumor component; this patient is now waiting for the second-stage intradural removal of the tumor. Complete tumor removal was accomplished in 21 cases and in one case, a residual schwannoma was left in place in the area of the jugular foramen. The 3 patients who were operated on by IFTA-A underwent permanent anterior transposition of the facial nerve. At 1-year follow up, 2 of these patients had House-Brackmann grade I and 1 reached grade IV. The patient who underwent a transcochlear-transjugular approach had a permanent posterior transposition of the facial nerve. At 1-year follow up, he had grade III facial nerve function. Postoperative facial nerve function was normal (House-Brackmann grade I) in all patients operated on by the POTS approach. Twelve patients had hearing-preserving surgery using the POTS approach. Good hearing was preserved in 10 cases (83.3%), the majority of whom (58.3%) maintained their preoperative hearing level. There was no perioperative mortality. One patient (4.5%) experienced a postoperative cerebrospinal fluid leak. After surgery, all patients did not recover the function of the preoperatively paralyzed lower cranial nerves. A new deficit of one or more of the lower cranial nerves was recorded in 50% of cases. So far, no patient has experienced recurrence during the follow-up period as ascertained by computed tomography or magnetic resonance imaging.

CONCLUSIONS

Surgical resection is the treatment of choice for jugular foramen schwannomas. The POTS approach allowed single-stage, total tumor removal with preservation of the facial nerve and of the middle and inner ear functions in the majority of cases. Despite the advances in skull base surgery, new postoperative lower cranial nerve deficits still represent a challenge.

Auditory Brainstem Implant in a Child with Severely Ossified Cochlea

OBJECTIVE

The hearing outcome after implanting a severely ossified cochlea has always been less satisfactory than implanting a patent one. The aim of our study is to present a case where brainstem implantation was successfully performed as an alternative to cochlear implantation in a child with bilateral severe ossification of the cochlea.

STUDY DESIGN

Case presentation. This study was conducted at Gruppo Otologico, Rome, Italy, a private referral center for neurotology and skull base surgery.

METHODS

The subject of our study was a 12-year-old female child with postmeningitic deafness and bilaterally ossified cochleae. This case is the first brainstem implantation performed at our center with the indication of severe ossification of the cochlea.

RESULTS

Successful brainstem implantation of a device was carried out, and the hearing of the patient was restored to the degree that she can freely use the telephone after 8 months of implantation.

CONCLUSION

Although more cases are needed before establishing the exact outcome of brainstem implantation in cases of deafness in the presence of severe bilateral cochlear ossification, preliminary results show the superiority of brainstem implants to conventional or even customized cochlear implants.

Revision Glomus Tumor Surgery

The infratemporal fossa approach type A is the best way to deal with recurrent tympano-jugular paragangliomas because facial nerve rerouting is fundamental to reaching the area of the internal carotid artery, where recurrence is likely to occur. Preservation of lower cranial nerve function is not feasible when there is tumor infiltration of the medial wall of the jugular bulb; any attempt at nerve dissection increases the risk of leaving some tumor remnants. Correct management of the internal carotid artery, including preoperative stent insertion or permanent preoperative balloon occlusion, is usually a fundamental step when dealing with these highly vascularized lesions. Because of the tumor tendency to infiltrate the bony structures, aggressive drilling of the temporal bone is also advised, especially at the level of the petrous apex. Patients affected by uncontrolled recurrences still die of this disease.

Technique to prevent post-operative CSF leak in the translabyrinthine excision of vestibular schwannoma

Cerebrospinal fluid (CSF) leak following VS removal is a challenging complication. With experience, it can be seen that anatomical factors such as the extent of pneumatization of the petrous temporal bone and posterior wall of the internal auditory canal play animportant role in contributing to CSF leak. Nevertheless, the risk of post-operative CSF leak remains a major concern for both the surgeon and patient. This paper describes a technique, which we have used since 1994, and which has helped us to achieve the lowest reported rate of post-operative CSF leak in translabyrinthine excision of vestibular schwannoma in the world literature.

Surgical Removal of Jugular Paragangliomas After Stenting of the Intratemporal Internal Carotid Artery: A Preliminary Report

OBJECTIVE

Jugular paragangliomas with extensive involvement of the internal carotid artery (ICA) represent a true challenge for surgeons, especially in the presence of inadequate collateral circulation through the circle of Willis. The aim of our study is to present a preliminary report of our experience with the surgical removal of three such cases using the stenting of the ICA as the method of choice for protecting and preserving the integrity of the artery.

METHODS

This retrospective study was conducted at Gruppo Otologico, a private referral center for neurotology and skull base surgery. The subjects of our study are three cases of jugular paragangliomas with extensive involvement of the ICA and inadequate collateral circulation. These cases are the first three cases operated at our center after stenting of the intratemporal portion of the ICA.

RESULTS

Complete surgical removal of the tumor, including the part involving the ICA, was achieved in all cases. Over a follow-up period of 22 to 30 months, no complications occurred and the patency of the stented arteries was preserved.

CONCLUSION

Although more follow-up is still needed before establishing the exact long-term outcome of stenting the intratemporal ICA, our preliminary report shows that the stent has facilitated the complete surgical removal of the tumor, preserving the integrity of the ICA.

Petrous bone cholesteatoma: management and outcomes

OBJECTIVE

Cholesteatoma of the petrous bone is a rare pathology that grows slowly and is often asymptomatic. High clinical suspect is recommended for its diagnosis. With the advancement of imaging, clinical diagnosis is confirmed and follow up is assured. The present study is presented to state our experience in management of petrous bone cholesteatoma (PBC) and an overview of the outcome results.

METHODS

This study was a retrospective case review conducted at a private quaternary referral center. From January 1984 to October 2004, 93 of 2,739 patients with chronic otitis media with cholesteatoma were treated surgically for PBC with varying location types.

RESULTS

The mean age in this study was 46 years. Ninety-four percent of patients presented with hearing loss. Facial paralysis constituted 55% of the presented manifestations and grade VI palsy was the most common. A massive type of PBC was found to affect 45% of patients and it was mainly the acquired pathology. The surgical approaches varied according to the class type of PBC. Postoperative complications were minimal, and follow up was carried out after 1 year from the surgery date.

CONCLUSION

Petrous bone cholesteatoma presents difficulties in its diagnosis and treatment. Adequate history-taking, high clinical suspicious, with the advancement of imaging techniques made its diagnosis more feasible. Improvement of the lateral skull base approaches rendered possible safe, adequate, and complete removal of the pathology.

Quality of Life After Acoustic Neuroma Surgery

OBJECTIVE

The aim of this study is to assess patients' quality of life after acoustic neuroma surgery, and if some patients' characteristics, parameters of tumor and surgical parameters affect patients' quality of life.

STUDY DESIGN

Retrospective study.

SETTING

Tertiary care center.

PATIENTS

A group of 386 patients who underwent acoustic neuroma surgery.

INTERVENTION

Patients included were derived from a population of 459 subjects operated for acoustic neuroma by the Otologic Group of Piacenza.

MEAN OUTCOME MEASURE

The outcome of the questionnaires on quality of life (SF 36), the Dizziness Handicap Inventory (DHI) and a questionnaire of patients' histories were analyzed.

RESULTS

In our sample a group of 231 patients were asymptomatic after surgery, while 155 patients reported very really disabling symptoms. Hearing loss was perceived as the most disabling symptom. The scores of questionnaire on quality of life were lower than scores for the normal population. The indices of disablement influenced the perception of quality of life.

CONCLUSION

Our study has shown that patients perceived a worsening of their quality of life, in particular women and patients over 45. Surgery caused a higher percentage of disability. Patients' quality of life can be used as a parameter for the timing of surgery. Our data indicate that an early surgical approach for intrameatal tumor is better than waiting for an increase in the tumor size. A "wait-and-scan" strategy for extrameatal neuromas which do not affect the brainstem is preferable, since these patients have a worsening of their quality of life after surgery independently of the tumor size.

Hearing preservation surgery in vestibular schwannoma

OBJECTIVES

To study the effect of pre-operative hearing level and tumour size on the hearing outcome of hearing preservation surgery for vestibular schwannoma.

STUDY DESIGN AND SETTING

A review of literature conducted at Gruppo Otologico, a tertiary referral centre for neurotology and skull base surgery.

RESULTS

A total of 1993 patients in 16 publications addressing the topic of hearing preservation surgery in vestibular schwannoma were analysed. The American Academy of Otolaryngology-Head and Neck Surgery hearing classification system was the classification upon which we based our analysis.

CONCLUSION

Defining hearing preservation as class-A hearing, there was a strong inverse relationship between pre-operative hearing and post-operative hearing levels and between tumour size and post-operative hearing levels.

Transapical extension in difficult cerebellopontine angle tumours: preliminary report

Difficult cerebellopontine angle (CPA) tumours namely large/giant vestibular schwannomas, vestibular schwannomas with a significant anterior extension and meningiomas of the posterior surface of the petrous bone extending anterior to the internal auditory canal (IAC) have always posed a problem for the otoneurosurgeon. Modifications of the enlarged translabyrinthine approach (ETLA) specifically aimed at dealing with these tumours are not reported. The aim of this paper is to introduce the transapical extension of ETLA which involves increased circumferential drilling around the IAC beyond 270°C. The extension allows enhanced surgical control over the tumour as well as the anterior aspect of the CPA including the prepontine cistern, the Vth and VIth cranial nerves. The extension is further classified into Type I and II depending upon the extent of drilling. Type I extension entails drilling around the IAC for 300–320° and is indicated for large/giant vestibular schwannomas (large vestibular schwannoma extrameatal diameter 3–3.9 cm, giant vestibular schwannoma extrameatal diameter [ges ]4 cm) and vestibular schwannomas with significant anterior extension. Type II extension involves complete drilling around the canal for 360° and is indicated for meningiomas of the posterior surface of the petrous bone extending anterior to the IAC.

Preoperative predictive factors for hearing preservation in vestibular schwannoma surgery

OBJECTIVES

We performed a retrospective chart review to evaluate the various predictive factors for postoperative hearing preservation in the surgical management of vestibular schwannoma.

METHODS

Of 792 patients operated on for vestibular schwannoma between April 1987 and July 2002, 107 were candidates for hearing preservation surgery. These patients were divided into group 1 (hearing preserved) and group 2 (hearing not preserved), and both of these groups were evaluated for age, sex, pure tone average, sound discrimination score, tumor size, and auditory brain stem response parameters. A corrected chi2 test and a corrected t-test were used for statistical analysis. Multiple regression analysis was further done to evaluate independent predictive factors, either alone or in combination. The results were evaluated by use of the modified Sanna classification and the guidelines of the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS).

RESULTS

Preoperative pure tone average and tumor size were the 2 predictive factors in our study. A Pearson correlation test showed that there was no multicollinearity between the factors. On multiple regression analysis by backward elimination of nonsignificant factors, we found that tumor size is an independent predictive factor for postoperative hearing. According to the modified Sanna classification, postoperative hearing was preserved in 11.2% of patients (equivalent to class A of AAO-HNS guidelines).

CONCLUSIONS

In our series, preoperative pure tone average and tumor size were found to be predictors of postoperative hearing levels.