Facial nerve outcome in non-vestibular schwannoma tumour surgery.

Problems/objectives: Tumour size, intra-operative electrophysiologic thresholds and postoperative facial nerve function have been demonstrated to be important predictors of ultimate facial nerve function after vestibular schwannoma surgery. In general little attention has been given to the prediction of outcome of facial nerve function in non-vestibular schwannoma tumour surgery of the cerebellopontine angle (CPA).

Methodology: A prospective study was performed to assess the predictive value of patient, tumour histology and electrophysiologic factors in the estimation of ultimate facial nerve outcome after this form of surgery.

Predictive factors of long-term facial nerve function after vestibular schwannoma surgery.

Objective: To assess predictive factors of long-term facial nerve function in a series of patients undergoing vestibular schwannoma surgery and to evaluate the reproducibility of the relevant parameters.

Study Design: Prospective.

Setting: Three tertiary referral neurotology units in two separate countries.

Delayed facial palsy after vestibular schwannoma surgery.

Objective: there is a lack of uniformity in the literature of the definition of delayed facial palsy (DFP) after vestibular schwannoma surgery. The aim of this study was to attempt to provide a clear definition of this clinical entity.

Methods: a prospective study was undertaken of all patients, with an intact facial nerve postoperatively, undergoing vestibular schwannoma surgery during a 16-month period.

Translabyrinthine removal of large acoustic neuromas in young adults.

Objective: the authors reviewed the clinical manifestations and the surgical outcomes in a series of young patients who underwent removal of large acoustic neuromas via the translabyrinthine approach.

Methods: 40 young adults who underwent a translabyrinthine removal of acoustic neuromas 3 cm or greater in size were analyzed. The patient's age ranged from 17 to 30 years.

[Auditory evoked potentials from brain stem determined in acoustic nerve neurinomas].

An analysis of the studies of Brain Stem Electric Response Audiometry of patients operated on Bachaumont Clinic or in Cochin hospital in Paris, because of acoustic neurinoma, was carried out. The studies comprised 88 patients divided into groups according to the size of tumour. A group of small intrameatal tumours, a group of up to 2 cm tumours, a group of between 2 and 3 cm tumours and a group of above 3 cm tumours.

Bilateral facial nerve schwannomas.

Facial nerve schwannoma is an uncommon tumor and bilateral facial nerve tumors are extremely rare. A case is presented in which neuromas affecting the intra-canalicular and labyrinthine portions of both facial nerves occurred. Radiologic assessment demonstrated the origin of these tumors.

Slow-growing labyrinthine masses: contribution of MRI to diagnosis, follow-up and treatment.

We report the use of MRI in the diagnosis, follow-up and therapeutic management of three cases of intralabyrinthine Schwannoma. The diagnosis was based on the history and initial and follow-up MRI findings. The main feature suggesting the diagnosis was a nodular intralabyrinthine mass of low signal intensity on T2-weighted images, and high or isointense signal on T1-weighted images (relative to cerebrospinal fluid), which showed contrast enhancement.

[Hemangioma of the facial nerve].

In this retrospective study the respective values of MRI and CT in the location and nature diagnoses of facial nerve haemangiomas were evaluated. The four male patients examined were 31, 44, 56 and 62 years old; they presented with facial nerve pals and/or cochlear-vestibular dysfunction. The haemangiomas were located in the internal auditory canal, the geniculate ganglion, the tympanic segment of the facial nerve and the petrous bone apex.

Unusual presentations of acoustic tumours.

A series of 238 consecutive patients with acoustic neuromas, operated on in Paris has been studied to identify unusual presentations and varied symptomatology. The most common history was that of a progressive unilateral hearing loss (in 68.1%), with tinnitus (in 49.

Screening for germ-line mutations in the NF2 gene.

Neurofibromatosis type 2 (NF2) is a monogenic dominantly inherited disease that predisposes to the development of tumors of the nervous system, particularly meningiomas and schwannomas. The gene which, when altered, causes NF2, is localized on chromosome 22 and has recently been identified. The NF2 gene is also the site of somatic mutation in tumors, suggesting that it might have a tumor suppressor activity.

[Surgery for meningioma of the posterior skull base. 135 cases. Choice of approach and results].

One hundred and thirty-five patients with posterior skull base meningiomas were seen and treated by a neurosurgical-neurotological team over the last 12 years. Ten tumors were "true" clival meningiomas and 125 were posterior petrous meningiomas: 25 were located anterior to the internal auditory meatus (IAM) (zone A); 29 were located around the IAM (zone M) and 18 were posterior to the IAM (zone P). 53 tumors had a larger zone of implantation and are accordingly called AM (31 cases), MP (15 cases), AMP (7 cases).

Preservation of facial, cochlear, and other nerve functions in acoustic neuroma treatment.

Between March 1966 and September 1992, 1400 acoustic neuromas were treated in Paris, France, by surgical excision. The findings over the last 7 years are presented. The translabyrinthine approach has been used in more than 85% of cases.

Retrosigmoid transmeatal approach: an anatomic study of an approach used for preservation of hearing in acoustic neuroma surgery and vestibular neurotomy.

The limitations of the transmeatal phase of the retrosigmoid transmeatal approach are shown, and the problems of opening the internal acoustic meatus via this approach and the criteria for its use are discussed.

[Acoustic neuroma].

The progress of the diagnostic and treatment of the acoustic tumors have begin in the years 1960. From this time, radio imaging, surgical and anasthesic techniques have improved in such a way that the lethality of the surgery is almost equal to 0% and the preservation of the facial mimic have reached a point that was never attained before. It must be emphasized that this surgery requires a surgical staff well trained and an appropriate structure.

Magnetic resonance imaging of acoustic neuromas: pitfalls and differential diagnosis.

A total of 162 patients with suspected acoustic neuromas underwent MR imaging at 1.5 T. All patients were injected with Gd DTPA or DOTA.

Magnetic resonance findings in 92 acoustic neuromas.

A retrospective analysis of the MR findings in 92 cases of acoustic neuromas is presented. The method of examination included in all cases intravenous injection of Gadolinium (Gd-DTPA or DOTA) with realization of sections in the axial and coronal planes. In 21 cases native MR studies were performed in the axial plane, before Gadolinium injection, with T1WI (n = 21), and T2WI (n = 6) images.

[Unusual circumstances of disclosure of acoustic neurinoma].

While progressive unilateral deafness remains the most typical symptom of the development of acoustic neuroma, the study of at least 1,200 cases operated since 1966 shows that in at least 16.5% of all cases, the triggering signal to seek medical advice was either otologic but atypical, or non-otologic but including symptoms in another pair of cranial nerves, or without any apparent relationship with the area showing a tumor of the eight pair, or even occurring under etiological circumstances that were misleading at first.

[Surgical technical note: apropos of cerebrospinal fluid fistula of the skull base].

Signs of a fistula of the C.S.F.

[Anastomosis of the facial nerve using fibrin glue, apropos of 60 cases].

The facial nerve was repaired with only fibrin glue anastomosis in 60 cases. The facial nerve was repaired by end-to-end (21 cases) or cable graft (28 cases) anastomosis. In 11 cases, a hypoglosso-facial anastomosis was performed.

[MRI in the diagnosis of recurrent cholesteatoma of the petrous bone].

Nine cases of recurrent petrous cholesteatomas have been studied by a 1,5 T MR unit. Gadolinium was injected in 1 case. In all cases, comparison between MR, CT and clinical findings were made.

[Life-threatening complications and severe neurologic sequelae in surgery of acoustic neurinoma].

Surgical treatment of acoustic neurinoma carries a high risk of mortality. Recent history of successful management sparing the facial, mixed, and even cochlear nerves, as well as of a substantially lower incidence of postoperative complications or neurological sequelae, should not give grounds for any false sense of security to undermine one's alertness during the pre, peri- and postoperative phases of the intervention. The overall mortality rate for surgical neurinoma cases was 0.