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At least 19 recordsLinked to original sources
PubMed2002

A case of multiple schwannomas of the trigeminal nerves, acoustic nerves, lower cranial nerves, brachial plexuses and spinal canal: schwannomatosis or neurofibromatosis?

In most cases, while schwannoma is sporadically manifested as a single benign neoplasm, the presence of multiple schwannomas in one patient is usually indicative of neurofibromatosis 2. However, several recent reports have suggested that schwannomatosis itself may also be a distinct clinical entity. This study examines an extremely rare case of probable schwannomatosis associated with intracranial, intraspinal and peripheral involvements. A 63-year-old woman presented with a seven-year history of palpable lumps on both sides of the supraclavicular area and hearing impairment in both ears. On physical examination, no skin manifestations were evident. Facial sensory change, deafness in the left ear and decreased gag reflex were revealed by neurological examination. Magnetic resonance imaging revealed multiple lesions of the trigeminal nerves, acoustic nerves, lower cranial nerves, spinal accessory nerve, brachial plexuses, and spinal nerves. Pathological examination of tumors from the bilateral brachial plexuses, the spinal nerve in the T8 spinal position and the neck mass revealed benign schwannomas. Following is this patient case report of multiple schwannomas presenting with no skin manifestations of neurofibromatosis.

Brachial Plexus Neuropathies↗
PubMed1985

MR imaging of the acoustic nerves and small acoustic neuromas at 0.6 T: prospective study.

To evaluate the capability of magnetic resonance (MR) in imaging normal acoustic nerves, 12 volunteers without signs or symptoms of intracranial disease were examined using a 0.6 T superconductive system. Several spin-echo (SE) pulse sequences were tested to identify the optimal sequence for demonstration of the acoustic nerve bundle. Repetition times (TRs) varied from 300 to 2000 msec and echo times (TEs) from 30 to 120 msec. A single-slice technique was used with 5 and 8 mm sections, one or two data acquisitions per projection, and axial and coronal imaging. The normal acoustic nerves were demonstrated readily by MR in axial and/or coronal sections. The distal parts of the nerves and tumors were imaged best with SE 1500/60. The medial extremities of the seventh and eighth nerves tended to be obscured in this sequence by brightening the cerebrospinal fluid signal adjacent to the brainstem, but they were demonstrated clearly with 500 or 800 msec TR and 30 msec TE. Five patients were studied who had hearing loss and evidence of retrocochlear disease. In four patients, MR imaging demonstrated five acoustic nerve tumors ranging in size from purely intracanalicular to a 12 mm cisternal component. In the fifth case, no tumor was identified by MR imaging or gas computed tomographic (CT) cisternography. Contrast-enhanced CT using a Siemens Somatom DR 3 or GE CT/T 8800 scanner failed to provide convincing evidence of tumor in any case, while gas CT cisternography was positive in all five tumors. All five acoustic neuromas were identified readily using the SE sequences that proved optimal for demonstration of normal nerves. This experience revealed that MR imaging can demonstrate the eighth nerve complex well and reliably. Single-slice (5 or 8 mm) technique is adequate, but multislice without tissue gaps (used recently) is more efficient. Small, even intracanalicular, acoustic neuromas are imaged effectively, indicating that the method is capable of superseding contrast CT cisternography, particularly with improving technology.

Atrophy↗
PubMed1987

[Intracranial schwannomas of the cranial nerves. The acoustic nerve excluded].

The schwannomas of the cranial nerves (except the IId and VIIIth nerves) are known to be infrequent although progress in diagnosis of these tumors have been obtained by C.T. scan. We report twelve cases involving the facial nerve and five cases of the caudal nerves that were developed into the foramen jugulare, and two cases of trigeminal schwannomas. One may suspect these tumors in presence of any minimal, unilateral defect of otological, facial, and pharyngo-laryngeal functions. The surgical approach to the tumors depends on both its location and symptomatology.

Adult↗
PubMed1983

Malignant nerve sheath tumor of acoustic nerve.

A malignant nerve sheath tumor of the acoustic nerve was found in a 54-year-old man whose right acoustic nerve signs had shown gradual worsening during the previous five years. No stigmata of von Recklinghausen's disease were noted. The tumor at autopsy extensively involved the brain stem, cerebellar hemisphere, tentorium of cerebellum, and cerebral occipitotemporal lobe on the right side. Histologically, the tumor was characterized by extreme hypercellularity, pleomorphism, and high mitotic activity. Ultrastructurally, there was an external lamina around the interdigitated cytoplasm of the tumor cells. Long-spacing collagens and junctional devices were also noted. This case is, to our knowledge, the first reported of a malignant nerve sheath tumor in the acoustic nerve.

Brain Neoplasms↗
PubMedDate not supplied

Pressure-induced modifications of the acoustic nerve. Part I: The acoustic reflex.

It is commonly thought that as an acoustic neuroma grows it exerts pressure on the acoustic nerve resulting in alterations of the acoustic reflex and brain stem audiometry. This hypothesis has not been confirmed. In this study in an animal model, acute pressure was applied to the nerves of the internal auditory canal, and changes in the acoustic reflex were measured. Our results support the theory that pressure on the acoustic nerve causes an increase in the rate of adaptation and a decrease in the amplitude of the acoustic reflex. The contralateral reflex appears to be the most sensitive indicator of these effects. We feel that this animal model can be useful to investigate the effects of pressure on the acoustic nerve.

Acoustic Impedance Tests↗
PubMed1975

[Bilateral tumors of the acoustic nerve and Recklinghausen's disease observed in several generations. Considerations on heriditary acoustic nerve tumors].

Since 1933, four families have been found in Marseilles with bilateral tumours of the acoustic nerve spread over three generations in three families. The fourth only showing a cutaneous neuro-fibromatosis in the second generation. The authors recall briefly the clinical characteristics and compare their cases with similar ones found in the literature. Bilateral and familial neurinomas of the VIIIth cranial verbes were found in 21 families, making a total of 111 cases, unilateral neurinoma being used as a term of comparison. Among the groups of cases published, the family observed by Gardner and Frazier is the most remarkable (43 cases over 6 generations). From the hereditary point of view, the phenomenon of antiposition is not always constant. From the evolutionary point of view, bilateral neurinomas manifest themselves earlier clinically than unilateral ones. As far as associations are concerned, cutaneous manifestations of neuro-fibromatosis are the most frequent if the neurinomas are bilateral and non familia. Among tumors of the nervous system, meningiomas and gliomas have been found, other dysembryoplastic or degenerative tumoral associations being rare. The incidence of cutaneous symptoms is very low when the neurioma is unilateral. The association of cutaneous symptoms with bilateral and familial neurinomas does not worsen the prognosis, but the presence of such cutaneous signs is significantly more serious if the neurinoma is isolated. These considerations do no more than touch the fringes of the problems raised by these sporadic or hereditary tumours of the VIII the cranial nerves, developing within the framework of phacomatosis. Great caution is necessary in assessing the correlations observed in view of the narrow range of statistics available.

Deafness↗
PubMed2000

[Malignant peripheral nerve sheath tumor with divergent cartilage differentiation from the acoustic nerve: case report].

Malignant peripheral nerve sheath tumors(MPNSTs) of the acoustic nerve are very rare. Only seven cases of MPNST arising from the acoustic nerve have been reported. The authors present a case of MPNST with divergent cartilage and melanotic differentiation of the acoustic nerve. The patient was a 69 year old man admitted to our neurosurgical service in January 1999 complaining of left facial nerve palsy and hearing difficulty of his left ear. The initial CT showed a tumor at the left cerebellopontine angle region. On MRI the tumor was depicted as low intensity on T 1-weighted image and high intensity on T 2-weighted image, the mass was heterogeneously enhanced after administration of Gd-DTPA. The partial removal of the tumor was performed in January 1999. He was discharged February 1999. But he was admitted again because of progressive cerebellar ataxia. MRI showed the rapid regrowth of the residual tumor. In March 1999, complete removal of the tumor was performed. Histopathological analysis revealed a malignant spindle cell neoplasm with divergent cartilage and melanotic differentiation. We review the relevant literature concerning MPNST of the acoustic nerve and discuss the clinical features of malignant eighth cranial nerve tumor.

Aged↗
PubMed1980

[Acoustic nerve adaptation in chronic acoustic trauma].

The adaptation phenomenon of the the cochlear nerve in the highest frequency region was studied by means of electrocochleography in the group of 32 persons exposed to prolonged noise and with noise-induced, mild hearing loss (in the 4--6 kHz region) and in 19 persons under the same conditions of noise-exposure but, without any evidence of the hearing loss. The same investigations were performed in the group of 27 normal-hearing persons and non-exposed to noise. In the whole group of persons exposed to prolonged noise, disregarding their hearing condition the amplitude-decrease of the action potential of the cochlear nerve due to the adaptation procedure, was twofold in comparison to the non-exposed persons. The latency of this potential was longer in the whole group of exposed to noise persons than in the intact persons. It was presumed that this type of auditory nerve adaptation results infinitial, ultrastructural noise-damage within the basal turn of the cochlea. Basing on the obtained results it was postulated that the adaptation phenomenon in the highest-frequency region can serve as an indicator of early noise-induced malfunction of the cochlea which probably precedes the highest-frequency threshold elevation in conventional audiometry.

Adaptation, Physiological↗
PubMed1982

Facial nerve preservation during surgery for removal of acoustic nerve tumors.

A series of 33 patients with 35 acoustic nerve tumors is reviewed. Tumor size was estimated from computerized tomography (CT) scans, and its influence on anatomical and functional preservation of the facial nerve was assessed. Six tumors (one invading the petrous bone, three medium and two large tumors) were not detected on CT scans. The translabyrinthine approach was used in seven instances (one small and six medium tumors) and the suboccipital transmeatal approach for 28 tumors (seven medium and 21 large tumors). Anatomical preservation of the facial nerve was achieved in 83% of operations for tumor removal, two of which were subtotal. A further two patients underwent subtotal removal, but the facial nerve was destroyed. Large tumors carried an increased risk of damage to the facial nerve, but even in this group the nerve was preserved anatomically intact in 70% of cases. Damage to the facial nerve occurred more frequently in patients with preoperative evidence of facial weakness; however, this factor did not appear to influence functional recovery of the facial nerve, provided that the nerve was intact at the end of the operation. A simple grading system for facial nerve function is described. Ony 76% of anatomically intact facial nerves showed any evidence of function 1 month after surgery. Postoperatively, facial function improved with time. At the latest review, 45% of these patients had normal facial function or mild facial weakness (Grades I and II).

Adolescent↗
PubMedDate not supplied

[Recovery of facial nerve function using sural nerve transplantation after its injury in acoustic nerve surgery].

INTRODUCTION: Statoacoustic n. neurinoma is a benign, slow-growing and usually unilateral tumor. During its growth the tumor exerts pressure on the surrounding anatomic forms within the pontocerebellar angle: cranial nerves, pons, cerebellum. Therefore the first clinical symptoms are ear buzzing and deafness, vision disorders, occipital headache or walking difficulties. The diagnosis of such conditions must be precise, whereas CT (computerized tomography) and MRI (magnetic resonance imaging) are the methods of choice. Surgical tumor removal is the only therapy, but during surgery facial nerve injury occurs. The objective of this paper is a case report of a facial nerve injury and sural nerve transplantation during acoustic neurinoma surgery and recovery of facial nerve function. CASE REPORT: A 23-year-old male patient suffered from ear buzzing in the right ear for a year and a half with gradual development of deafness. Due to frequent headaches and after ophthalmologic examination, the patient was urgently hospitalized at the Neurology Clinic of the Faculty of Medicine in Novi Sad where MRI of the endocranium was performed revealing a tumor of the pontocerebellar right angle, 3 x 3.5 cm in size. The patient has undergone surgery at the Neurosurgery Clinic of the Faculty of Medicine in Pees in Hungary, with suboccipital craniotomy and tumor ablation. During surgery facial nerve injury occurred in the premeatal segment and intraoperative transplantation of sural nerve grafts from the left leg to the distal parts of the facial nerve was performed. The histopathologic finding revealed an acoustic neurinoma (Schwannoma). After surgery a control CT was performed revealing a complete tumor removal. The wound healed per primam intentionem and the patient was released from hospital two weeks later. During the postoperative period physical therapy was performed in the aim of rehabilitation of the facial nerve due to peripheral paralysis. After electrodiagnostic tests using GALVOMED 20 apparatus, massage was performed in the periorbital and perioral regions. Kinesitherapy was also done in front of a mirror several times a day. 6 months after surgery an EMG (electromyography) of m. frontalis dx., m. orbicularis oculi dx. and m. orbicularis oris dx. were performed. The EMG revealed evident reinnervation possibilities. A year after surgery the control MR finding of the endocranium was regular, as well as the control MR two years after surgery (postoperative cyst without signs of recurrence of the removed neurinoma). Control EMG of the m. frontalis dx., m. orbicularis oculi dx., m. orbicularis oris dx. showed signs of reinnervation. DISCUSSION: Tumors of the pontocerebellar angle are usually acoustic nerve neurinomas. 8% of intracranial tumors are Schwannomas. They originate from neurilemmal cells, by rule they grow slowly and are benign tumors. Therefore, for years the only signs pointing to them are ear buzzing and gradual development of deafness. That is why these anamnestic data are important for diagnosis. Headaches, walking difficulties, vision disorders are the usual difficulties due to which patients seek doctor's help. Computerized tomography and magnetic resonance imaging represent the diagnostic methods of choice in establishing the diagnosis. In this case MRI was performed on time. Surgery is the only therapy, but during tumor ablation the facial nerve was injured in the premeatal region. Intraoperative transplantation of grafts taken from sural nerve to proximal and distal parts of the facial nerve provides possibilities for injured nerve regeneration. The process of regeneration of such a nerve is long-term and often permanent 40% axon loss occurs. This is the reason to perform a control EMG two years after surgery. During peripheral paralysis rehabilitation is performed in the aim of preventing contractures. It is achieved by passive exercises in front of a mirror a few times a day. (ABSTRACT TRUNCATED)

Adult↗