30 research outputs found
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Is surgical excision of facial nerve schwannomas always indicated?
The Long-term Follow-up of Drainage Procedures for Petrous Apex Cholesterol Granulomas
OBJECTIVE: To determine the long-term effectiveness of various approaches to surgical drainage of petrous apex cholesterol granulomas. DESIGN: A retrospective cohort study in which patients treated by surgical drainage for petrous apex cholesterol granulomas were followed up for a minimum of 1 year (mean, 4.6 years). SETTING: House Ear Clinic, an otologic tertiary care center in Los Angeles, Calif. PATIENTS: A total of 25 patients who underwent either transcanal infracochlear, infralabyrinthine, middle fossa, or translabyrinthine drainage and who had at least 1 year of clinical and, in some cases, radiologic postoperative follow-up. MAIN OUTCOME MEASURES: Relief or recurrence of symptoms, need for revision surgery, postoperative hearing, appearance on postoperative imaging studies. RESULTS: Twenty-three patients had improvement or complete resolution of preoperative noncranial nerve VIII nerve dysfunction. Hearing was preserved in cases of middle fossa, infralabyrinthine, and infracochlear approaches with serviceable preoperative hearing. Hearing did not improve in cases of total preoperative hearing loss. Of the patients who underwent postoperative imaging, over three fourths had reduction in lesion size and one third developed aeration of the petrous apex. Revision surgery was required in three patients. Recently developed, the infracochlear approach has shown excellent early results. Lesion size was reduced in five of five patients, and the petrous apex contained air in three of five patients who underwent the infracochlear approach. CONCLUSION: Drainage via the infracochlear and infralabyrinthine approaches offers effective long-term decompression of petrous apex cholesterol granulomas, while preserving hearing.(Arch Otolaryngol Head Neck Surg. 1995;121:426-430
Treatment of Recurrent and Residual Glomus Jugulare Tumors
Residual and recurrent glomus jugulare tumors are rare but challenging. Treatment options include microsurgical resection, stereotactic radiotherapy, a combination of modalities, and “observation.” Choice of treatment must be made on a case-by-case basis, considering patient age, health status, location and size of tumor, status of the lower cranial nerves, and, of course, patient desire. Surgery is preferred when total resection of the tumor with preservation of function is deemed achievable. When function of the lower cranial nerves has been compromised, total surgical resection may also be possible, provided that the patient's health allows it. Cases where function is still preserved despite presence of a large tumor are more challenging, and a combination modality may be most effective. The goal of treatment is to provide tumor control with low morbidity. Current surgical techniques and the availability of stereotactic radiotherapy make this possible in the majority of cases
Nerve crush but not displacement-induced stretch of the intra-arachnoidal facial nerve promotes facial palsy after cerebellopontine angle surgery
Little is known about the reasons for occurrence of facial nerve palsy after removal of cerebellopontine angle tumors. Since the intra-arachnoidal portion of the facial nerve is considered to be so vulnerable that even the slightest tension or pinch may result in ruptured axons, we tested whether a graded stretch or controlled crush would affect the postoperative motor performance of the facial (vibrissal) muscle in rats. Thirty Wistar rats, divided into five groups (one with intact controls and four with facial nerve lesions), were used. Under inhalation anesthesia, the occipital squama was opened, the cerebellum gently retracted to the left, and the intra-arachnoidal segment of the right facial nerve exposed. A mechanical displacement of the brainstem with 1 or 3 mm toward the midline or an electromagnet-controlled crush of the facial nerve with a tweezers at a closure velocity of 50 and 100 mm/s was applied. On the next day, whisking motor performance was determined by video-based motion analysis. Even the larger (with 3 mm) mechanical displacement of the brainstem had no harmful effect: The amplitude of the vibrissal whisks was in the normal range of 50A degrees-60A degrees. On the other hand, even the light nerve crush (50 mm/s) injured the facial nerve and resulted in paralyzed vibrissal muscles (amplitude of 10A degrees-15A degrees). We conclude that, contrary to the generally acknowledged assumptions, it is the nerve crush but not the displacement-induced stretching of the intra-arachnoidal facial trunk that promotes facial palsy after cerebellopontine angle surgery in rats