Diagnosis Of Facial Nerve Schwannoma Research Articles

A Case of Supralabyrinthine Petrous Bone Cholesteatoma Mimicking Facial Nerve Schwannoma

We report the case of a 31-year-old woman with a supralabyrinthine petrous bone cholesteatoma who presented with acute facial paralysis, without other symptoms; she had first noticed the symptoms 2 months earlier. She was prescribed oral steroid therapy at a previous clinic, which had proved ineffective. Examination revealed a normal appearance of the tympanic membrane, and pure tone audiometry showed no evidence of hearing loss. Computed tomography (CT) revealed a spindle-shaped soft-tissue lesion occupying the labyrinthine segment of the facial nerve coursing to the epitympanum. Gadolinium-enhanced magnetic resonance imaging (MRI) revealed a non-enhancing mass in the same region. A provisional diagnosis of facial nerve schwannoma was made on clinical and radiological grounds, and surgical resection was performed via a middle fossa approach. Keratin debris was found along the labyrinthine segment of the facial nerve coursing to the ossicles, which led us to make the diagnosis of cholesteatoma. The lesion was completely resected along with the head of the malleus and incus by mastoidectomy, and ossiculoplasty was performed. Histological examination confirmed the diagnosis of cholesteatoma. The patient’s facial paralysis failed to recover. In patients with a small lesion in the petrous bone who present with isolated facial palsy as the only clinical manifestation, it is often difficult to differentiate between a cholesteatoma and facial nerve schwannoma, and gadolinium-enhanced MRI is a useful imaging examination to differentiate between the two diseases. In the present case, facial nerve schwannoma was suspected as the most likely diagnosis based on the clinical presentation and CT findings; however, the lack of enhancement on gadolinium MRI pointed to the diagnosis of cholesteatoma. Physicians should be aware of these clinical aspects for appropriate treatment planning.

Unusual acute hearing loss after gamma knife surgery for a facial schwannoma

A 34-year-old female patient suffering from right-sided facial palsy presented to our hospital. Her hearing range was within normal limits. She had undergone GKS after receiving a diagnosis of facial nerve schwannoma (FNS). On the fourth day after GKS, the patient experienced sudden onset hearing loss on the right side without aggravation of the facial palsy. Intravenous corticosteroids were administered, and her hearing function improved gradually over the course of 15 days. This is the first case report of hyperacute hearing loss after GKS for FNS.

Schwannomas along Different Segments of Facial Nerve: Case Series with Review of Literature

ABSTRACTFacial nerve schwannomas are rare conditions which can mimic many other conditions. A series of patients with facial nerve schwannomas were treated in our department, all of whom had a delay in diagnosis resulting in a significant morbidity. This prompted us to present this rare case series of schwannomas along different segments of facial nerve and also review the literature on such tumors—the different presentations, work-up issues in management and rehabilitation. A wide text and PubMed English literature-based search was done on the existing literature on facial nerve schwannomas and the summary presented. Facial nerve schwannomas can have multiple clinical presentations with or without a facial paresis. Only a high degree of clinical suspicion and early imaging can lead to this diagnosis. An early diagnosis of facial nerve schwannoma is important as the morbidity associated with the condition as well as the surgery increases with the delay in diagnosis.

Diagnosis of Facial Nerve Schwannoma by Magnetic Resonance Imaging Enhancement of the Geniculate Ganglion

diagnosis of facial nerve schwannoma was based on this enhancement pattern. The patient had a retromastoid craniotomy and intentional subtotal tumor resection. Intraoperatively, the normal-appearing portion of the right facial nerve was identified and noted to be contiguous with the tumor. The pathologicdiagnosiswasschwannoma.No operative complications occurred. Ten months postoperatively, the patient had radiosurgery of the residual tumor. One year after radiosurgery, the patient had full facial sensation, no eye dryness, and mild facial asymmetry. Follow-up imaging showed that the residual tumor had decreased in size (Figure 2), and the patient has returned to work. COMMENT

Facial Nerve Schwannoma Presenting as a Mass in the Middle Cranial Fossa: Typical Neuroradiological Patterns for a Preoperative Diagnosis

Facial nerve schwannoma is a rare primary neurogenic tumour that may originate anywhere along the VII(th) nerve course. The clinical presentation is highly dependent on the location of the lesion along the nerve course and this makes the pre-operative diagnosis difficult without radiologic examination. The most common presentation is facial palsy and even though tumours are responsible for only 5% of facial palsies, if a patient does not recover within six months a complete work-up for neoplasm is recommended. On the basis of clinical presentation and imaging characteristics radiologists should try to make a preoperative diagnosis, to help in the patient's management and possibly to plan the surgical approach. We describe the case of a successful preoperative diagnosis of facial nerve schwannoma. The aim is to describe the main CT and MRI findings which may help the radiologist to establish a correct differential diagnosis.

Intraoperative diagnosis of facial nerve schwannoma at parotidectomy

Objective Our objective was to provide a diagnostic algorithm for facial nerve schwannomas presenting as a parotid mass. Study design The study is a case report and literature review. Methods A clinical case of a patient with an asymptomatic parotid mass diagnosed as a facial nerve schwannoma intraoperatively is presented. The patient's presentation and the diagnostic algorithm and surgical rationale are discussed. A review of the literature on facial nerve schwannomas is presented. Conclusions Intraparotid facial nerve schwannomas are an extremely rare entity and are rarely diagnosed preoperatively. Most of these benign lesions can be managed conservatively with the goal of preserving facial nerve function. Intraoperatively, fine-needle aspiration and/or conservative biopsy in a nonstimulating portion of the lesion can be used to make the diagnosis.

Facial nerve schwannoma in the inner auditory canal and geniculate ganglion

Schwannoma of the vestibular nerve is the most common tumor found in the inner auditory canal. If a schwannoma of the facial nerve is found unexpectedly during surgery, the original surgical plan may have to be changed. In our series, we describe the symptoms, diagnostic procedures and therapy of this infrequent, benign tumor. In particular, we want to analyse the influence of diagnostic techniques, such as magnetic resonance tomography and electrophysiology, on the diagnosis of these tumors. Between 1975 and 2001, we diagnosed 17 cases of facial nerve schwannoma in the inner auditory canal or the geniculate ganglion. All patients were treated surgically. In 16 cases, we used the enlarged middle fossa approach and in the remaining patient the translabyrinthine approach was used. In 11 cases, the facial nerve could be saved but in six the nerve had to be rebuilt with a transplant. During the first years of our study, palsy of the facial nerve was a frequent finding. In the later years, a hearing impairment and tinnitus became the most frequent symptoms. Advances in magnetic resonance imaging have, in many cases, facilitated the differentiation between schwannomas of the facial nerve and the vestibular nerve over the last years. Signal enhancement at the geniculate ganglion is important for the diagnosis of facial nerve schwannoma. In individual cases, we found significant findings using electrophysiological procedures. In three cases, the temporal delay was elongated. Based on these findings, the therapeutic procedures can be discussed together with the patients.