Bilateral acoustic neuromas

This article reviews 12 patients with bilateral acoustic neuromas. The sex incidence was equal and the mean age at diagnosis was 26.2 years. The family history was positive in nine of the patients. Five patients have had incomplete surgical removal of acoustic neuromas on both sides. Two of them are completely deaf and the other three have severe sensorineural hearing loss in one ear and no hearing in the other ear. In five patients the tumour on one side has been operated on and the other side is being observed with at least short-term preservation of good hearing. The remaining two patients died of intra-cranial complications, one of them post-operatively. Four patients developed facial palsy immediately following surgery and one developed facial weakness 6 months after surgery. Guidelines are discussed for the care of these patients including the timing of surgery and alternative treatment options (observation, radio-surgery adn chemotherapy). This is essentially a group of young individuals who have had multiple operations for bilateral acoustic tumours and associated manifestations and for whom the disease and the sequelae of treatment can be tragic.     

Computed tomography for small acoustic neuromas

Summary The minimal size of acoustic neuromas detectable by computed tomography (CT) is, according to the available literature, 1.5 to 2 cm. The new otoneurosurgical technic using the transtemporal and translabyrinthine approach necessitates an early diagnosis of neuromas protruding 1 cm or less into the cerebellopontine angle cistern. This seemed impossible with the available CT equipment. Eight proven acoustic neuromas 1 cm or less in diameter, detected with CT, are reported. Diagnostic criteria are elaborated. The study shows that small cerebellopontine angle tumors can be detected by use of CT machines of the newer generation which perform scanning with thin and overlapping slices.     

Hypoglossofacial anastomosis for facial palsy after resection of acoustic neuroma

Twelve patients with facial palsy after resection of acoustic neuromas were treated by hypoglossofacial anastomosis. The nerve anastomosis were performed 1-2 months after resection of the tumor in 10 cases (group A). Two cases (group B) had the anastomosis performed more than 2 years after damage to the facial nerve. All the cases had been followed for more than 9 months. The results of reinnervation of the paralyzed facial muscles were quite satisfactory, i.e., over 80% of the cases obtained a good functional recovery. Although there was a 2-month delay in functional recovery of group B patients, the final results were practically the same in both groups. Therefore, the effect of the duration of the paralysis of the facial nerve seems to be less important in facial nerve surgery than in nerve surgery of the extremities. The procedures of anastomosis of descendens hypoglossi to the distal stump to the hypoglossal in 7 of the 10 patients using the hypoglossal as the donor nerve was of little help in prevention or restoration of the hemiatrophy of the tongue. In spite of long-term inconvenience in speaking and eating after section of the hypoglossal, all the patients were able to make enough adjustments about 2-3 months after nerve surgery.     

小脑桥脑角占位性病变的CT表现和诊断

分析１１４例经手术病理或脑血管造影证实的ＣＰＡ占位性病变的ＣＴ表现。ＣＰＡ脑外病变的定位征象有脑组织受压移位，患侧桥池和／或环池增宽，宽基底与岩骨相贴，岩骨侵蚀破坏，肿瘤轮廓清晰，瘤周水肿少见且程度轻。脑内病变延伸至ＣＰＡ表现为病变大部分位于一侧小脑半球或脑干，向患侧ＣＰＡ延伸，患侧桥池和／或环池受压变窄或闭塞。患侧桥池和／或环池增宽与否是鉴别ＣＰＡ病变来自脑外或脑内的重要征象。     

听神经瘤切除术的护理体会

听神经瘤是颅内较少见的肿瘤,由于其位置深,局部解剖复杂,手术难度大,我院过去做此手术较少,近年来,随着脑外科技术的改进,特别是双极电凝及显微技术的发展,使听神经瘤的患者,在我院能得到手术切除并取得成功[1]。我院自2001年至2005年3 a中共收治听神经瘤病人20例,现将手术护理体会总结如下。1临床资料本组20例,男12例,女8例,年龄26岁64岁,平均45.2岁。病程6个月8 a,平均3.8 a。首发症状为病侧耳鸣、耳聋16例(80%),步态不稳14例(70%),眼睑闭合不全12例(60%),声嘶、吞咽困难4例(20%)。本组均在全麻下经枕下入路行听神经瘤切除术,无死亡。2术…     

伽玛刀治疗听神经瘤28例初步报告

本文报告28例听神经瘤的伽玛刀治疗，28例中，属于术后残留或复发者占11例，双侧者1例。本组病例治疗后随访1－4月，尚未见不良反应．初步认为，对于一些年龄大不适合手术，或手术后残留肿瘤复发患者，病人不愿再手术者，采用r－刀治疗是一种安全简便的治疗方法。     

Acoustic neuroma surgery and delayed facial palsy

Delayed onset of facial palsy is possibly an underestimated but distressing complication of acoustic neuroma surgery. The incidence of this complication reported in the literature has varied from 11.7 to 41%.This study reviewed retrospectively 60 primary acoustic neuroma surgeries performed by a single neurotologist. The deelayed onset of facial dysfunction was defined according to the guidelines described by of Lalwani Butt, Jackler, Pitts and Jingling in 1995. They considered either a deterioration of facial function from normal to abnormal or an increased severity of the degree of facial paralysis, which was grouped using the House-Brackmann scale system. Fifteen of the 60 patients (25%) were found to have a deterioration of facial function. The incidence of delayed facial palsy was not influenced by age, sex or tumor size. The majority of the patients had a favorable prognosis. Only three patients had a grade III–IV facial function at 1 year. It is possible that these latter cases might have benefited from intraoperative meatal facial nerve decompression, as advocated by Sargent, Kartush and Graham. Received: 27 August 1997 / Accepted: 31 October 1997     

Amputation neuroma of the orbit. Report of two cases and review of the literature

Two patients developed proptosis and a slowly enlarging mass with increasing discomfort in the orbital socket 17 and 25 years following enucleation. Preoperative CT scans revealed a single cystic structure within the orbits of each case with distinct soft tissue tumors adjacent to the cysts. The cystic structures and the adjacent solid masses were removed en bloc necessitating reconstruction of the orbits with a dermal fat pad (case 1) and a mucous membrane graft (case 2). Postoperatively the patients were free of complaints. Microscopically, the cystic structures were identified as conjunctival inclusion cysts while the soft tissue masses were traumatic neuromas with irregular tangles and whorls composed of proliferated axons, Schwann cells and connective tissue. Only seven amputation neuromas of the orbit have been reported. Pain related to the neuroma is rarely encountered and is probably caused by mechanical irritation of the amputation neuroma, by retracting scar tissue, or compression from an adjacent cystic mass as in one of our cases.     

Mobile phone use and acoustic neuroma risk in Japan

Objectives

The rapid increase of mobile phone use has increased public concern about its possible health effects in Japan, where the mobile phone system is unique in the characteristics of its signal transmission. To examine the relation between mobile phone use and acoustic neuroma, a case‐control study was initiated.

Methods

The study followed the common, core protocol of the international collaborative study, INTERPHONE. A prospective case recruitment was done in Japan for 2000–04. One hundred and one acoustic neuroma cases, who were 30–69 years of age and resided in the Tokyo area, and 339 age, sex, and residency matched controls were interviewed using a common computer assisted personal interview system. Education and marital status adjusted odds ratio was calculated with a conditional logistic regression analysis.

Results

Fifty one cases (52.6%) and 192 controls (58.2%) were regular mobile phone users on the reference date, which was set as one year before the diagnosis, and no significant increase of acoustic neuroma risk was observed, with the odds ratio (OR) being 0.73 (95% CI 0.43 to 1.23). No exposure related increase in the risk of acoustic neuroma was observed when the cumulative length of use (<4 years, 4–8 years, >8 years) or cumulative call time (<300 hours, 300–900 hours, >900 hours) was used as an exposure index. The OR was 1.09 (95% CI 0.58 to 2.06) when the reference date was set as five years before the diagnosis. Further, laterality of mobile phone use was not associated with tumours.

Conclusions

These results suggest that there is no significant increase in the risk of acoustic neuroma in association with mobile phone use in Japan.