前庭诱发的肌源性电位原理与应用

前庭诱发电位的引出较脑干、视觉和体感诱发电位困难.争论主要集中在:(1)在旋转刺激中,眼震反应是加速与减速的均值;(2)记录到的反应是双侧反应,无法识别受累侧别;(3)反应是否来源于前庭还有争议;(4)方法复杂、引起受试者明显不适.所有这些都表明前庭诱发电位尚不能应用于临床,而实际上目前也只是处于动物实验的水平.尽管神经源性的前庭诱发电位还有争议,但晚近出现的声诱发肌源性电位强烈提示来源于前庭.这种电位被命名为短声诱发的前庭丘脑反应或前庭诱发的肌源性电位(vestibular evoked myogenic potentials,VEMPs)用以与神经源性的前庭诱发电位相区别.     

前庭终器损害前后瘘管刺激前庭诱发电位的观察

目的在以往工作的基础上,进一步证明瘘管刺激前庭诱发电位的应用价值.方法14只健康白色红目豚鼠分成用药组(8只)和正常对照组(6只).用药组每天肌肉注射庆大霉素230mg/kg,持续5d.记录两组动物的前庭诱发电位.结果扫描电镜证实该组动物壶腹嵴、囊斑毛细胞出现不同程度病理改变,基底膜毛细胞形态正常,瘘管刺激前庭诱发电位测试,见该诱发电位P1～P4各波振幅明显下降,与正常对照组比较有显著差异,而听性脑干反应(ABR)测试结果两组未见显著性改变.结论瘘管刺激前庭诱发电位可以作为显示前庭系病变客观和直接的观察指标,并有定位诊断价值.     

实验性瘘管刺激前庭诱发电位面神经管电极记录

目的研究在颅顶电极引导瘘管刺激前庭诱发电位基础上,进行面神经管电极引导方法的实验观察。方法取６只健康纯白豚鼠,同时安放颅顶电极和右面神经管电极,进行瘘管刺激前庭诱发电位测试记录。前庭刺激方法为上半规管开窗,藉特殊设计的瘘管刺激探针机械刺激壶腹嵴,诱发前庭电位。结果发现面神经管电极前庭诱发电位主要由一个振幅很大的Ｐ波构成,该波与颅顶电极法的Ｐ１波潜伏期相同。结论二者潜伏期及波宽呈正相关,提示二波源于同一神经结构,考虑到面神经管电极ＥＣｏｃｈＧ以显示听神经动作电位为主,推测Ｐ波和Ｐ１波很可能代表了前庭神经的动作电位。     

豚鼠电刺激诱发前庭神经核场电位特征

目的 探讨电刺激前庭诱发电位的特征.方法 双银丝刺激电极放置于圆窗表面,在电刺激条件下采用玻璃微电极记录前庭神经核的场电位.结果 电刺激诱发的前庭场电位主要由一个负波(N1)构成,其振幅随微电极在前庭神经核的位置而变化.电流和电压刺激的阈强度分别为0.59±0.07 mA和0.90±0.50 V,1.5倍阈强度的电流刺激时N1波的潜伏期为1.20±0.13 ms,对间隔小于4 ms的双刺激中的第二次刺激无反应或者反应减低.结论 迷路刺激能有效地兴奋前庭神经诱发前庭神经核神经元的场电位,且电位相当稳定.     

前庭诱发电位的现状

经过晚近十年的努力，世界各国有志于前庭诱发电位事业的学们已采用多种刺激在实验动物及人类记录出较为满意的前庭诱发电位，本就各种刺激诱发的电位的特点，所记录电位前庭源性的证实、各波起源以及潜伏期前庭诱发电位的初步应用进行综述。     

前庭诱发电位

前庭诱发电位，又称前庭诱发肌源性电位(vestbular evoked myogenic potentials，VEMPs)，是指用高强度声刺激一侧球囊并在紧张的胸锁乳突肌(SCM)上记录肌源性电位来反映人前庭丘脑通路完整性的一种客观、无创的电生理测试技术，对于前庭系统及其相关疾病的诊断具有重要的临床应用价值。现从VEMPs的起源、检测方法、波形意义、影响因素及其临床应用等方面加以阐述。     

前庭诱发肌源性电位

前庭器官及与之关联的脑内各级中枢组成前庭系统,司体位感觉及平衡,各种平衡失调及表现不一的眩晕病是耳科及神经科的多发病,病因常不易确诊.由于技术上的难度,前庭功能的检查方法一直较为落后.惯用的大幅度旋转方法虽然也不断在改进,但通用的眼震等类指标都较为间接.虽然加速度刺激及电刺激记录前庭诱发电位是一项新技术,可直接提供有关前庭系统各级结构功能状态的信息,但目前尚无可用于临床检查的商品仪器.所以寻找其它的方法反映前庭功能是当前面临的重要任务.短声刺激前庭(球囊)诱发肌源性(颈肌)电位,能间接地反映前庭系统的功能,且操作方法简单易行,反应具有单侧性,是一个很有前景的临床检查方法.本文就其概念、研究概况及实验对象、方法、电位的起源、传导途径、影响因素及临床应     

《前庭诱发肌源性电位的实践：方法、常见错误和临床应用》摘译与解读

前庭诱发肌源性电位（VEMP）是一项评估耳石器及前庭神经传导通路的检查技术。通过气导声或振动刺激耳石器，在颈部和眼部肌肉部位记录的电反应活动，分别称为颈肌前庭诱发肌源性电位（cervical VEMP，cVEMP）和眼肌前庭诱发肌源性电位（ocular VEMP，oVEMP）。由于测试条件不同，可导致测试质量和结果出现较大差异，因此规范检查技术的质量是应用于临床检测的重要前提要素。本文在Papathanasiou等cVEMP临床指南（2014年）基础上，系统的介绍了VEMP的操作和临床应用测试方案。特别是对刺激和记录等参数设置，DOI: 10.16066/j.1672-7002.2020.08.006 全民健康助力全面小康·前庭诱发肌源性电位检查技术专题：继续教育园地提供相应的理论依据；列举出操作中一些常见的错误及解决方案；最后概述VEMP的临床应用。与此同时，中国康复医学会眩晕康复专业委员会联合中国医药教育协会眩晕专业委员会于2019年在《中华耳科学杂志》也发布《前庭诱发肌源性电位临床检测技术专家共识》，希望将VEMP技术进一步规范，促进该技术在国内临床和科研机构的规范应用。     

直流电刺激诱发的前庭诱发肌源性电位儿童检测方法的建立

目的 建立健康儿童直流电刺激诱发(galvanic vestibular stimulation, GVS)的颈肌前庭诱发肌源性电位(cervical vestibular evoked myogenic potential, cVEMP)和眼肌前庭诱发肌源性电位(ocular vestibular evoked myogenic potential, oVEMP)的检测方法,并确定正常范围。方法 对健康儿童20例(3～14岁)和健康成人24例(18～30岁)分别进行GVS-cVEMP和GVS-oVEMP检测,儿童组直流电刺激强度不超过3 mA,成人组最大刺激强度5 mA,记录两组GVS-cVEMP和GVS-oVEMP的引出率和特点,并进行不同刺激强度下的疼痛评分。结果 GVS-cVEMP和GVS-oVEMP在儿童组和成人组的引出率均为100.0%。儿童组GVS-cVEMP的p1潜伏期、n1潜伏期和p1-n1波间期分别为10.46±1.84 ms、16.98±2.12 ms和6.52±1.42 ms, n1潜伏期和p1-n1波间期较成人组明显缩短(P<0.05)。儿童组GVS-o...     

声刺激诱发麻醉豚鼠前庭咬肌反射及起源的研究

目的 建立声诱发前庭咬肌反射的动物模型,探讨咬肌反射电位的特征及起源.方法 20只豚鼠,随机分为正常对照组(10只)、单侧前庭下神经切断组(5只)、单侧耳蜗神经破坏组(5只).3组动物分别在麻醉下于豚鼠下颌骨及颅顶之间用金属夹夹住,使咬肌保持一定的张力,记录click声诱发的咬肌反射电位,并进行听性脑干反应(ABR)测试.结果正常对照组豚鼠声诱发咬肌反射电位的负波(negative peak,NP)阈值为92±7.68dB nHL.给予100、90、80、70 dB nHL单侧声刺激时,同侧记录咬肌反射NP引出率分别为100%、7O%、40%、0%.给予100、90、80 dB nHL单侧声刺激时,同侧记录咬肌反射NP平均潜伏期分别为6.57±0.26、6.64±0.23、6.69±0.19 ms,不同刺激强度下NP潜伏期差异无统计学意义(P>0.05).ABR的平均反应阈为31±7.88 dBnHL.单侧前庭下神经切断组术侧声诱发咬肌反射消失,ABR反应阈在正常范围内.单侧耳蜗神经破坏组术侧声诱发咬肌反射存在,NP阈值及潜伏期与正常对照组差异无统计学意义(P>0.05),ABR消失.结论 在豚鼠下颌骨及颅顶之间应用金属夹使咬肌保持一定的张力,同时给予click声刺激,可以建立一个理想的声刺激诱发前庭咬肌反射的动物模型;声刺激诱发的豚鼠咬肌反射电位NP来源于前庭,且该反射是肌源性的.     

A Decrease in Maxillary Sinus Pressure,as Seen in Upper Airway Allergy or Infection,Results in an Increase in Upper Airway Nitric Oxide Levels

The paranasal sinuses are connected to the nasal cavity via small osties. Ostial occlusion, caused by mucosal swelling, will result in a slowly increasing negative pressure inside the sinus cavity. In parallel, the oxygen content in the sinus will decrease, resulting in the development of relative hypoxia. Hypoxia is a powerful inducer of nitric oxide (NO) synthase, and inducible NO synthase has been shown to be present in considerable amounts in the upper airways, including the sinuses. The present study was designed to investigate whether a reduction in sinus pressure would affect upper airway NO production. Thirteen healthy volunteers were investigated. A pressure chamber was used to lower the ambient pressure to-4.9 kPa. NO was sampled from one nostril or via a drainage tube inserted into the maxillary sinus before, during and after the hypobaric exposure. When the pressure was decreased, NO levels increased from 256 &#45 15 to 316 &#45 19 ppb ( n =13, p <0.001). The NO levels remained elevated (282 &#45 21 ppb; p <0.05) when measurements were repeated 20 min after leaving the chamber. The nasal airway resistance (V2 tot ) also increased as a result of the chamber session (from 16 &#45 2° before to 21 &#45 3° after; p <0.05). An increase in NO levels was also found when the experiments were repeated with NO sampled directly from the maxillary sinus (225 &#45 6 before and 265 &#45 9 ppb after; n =6, p <0.001). For control purposes the nasal analyses were repeated again, this time under hyperbaric conditions (+4.9 kPa). This resulted in a slight decrease in the NO levels (from 273 &#45 22 to 241 &#45 17 ppb; n =10, p <0.001), but there was no change in the nasal airway resistance. We conclude that a reduction in sinus pressure, as seen in upper airway allergy or infection, may result in an increase in upper airway NO production.     

One‐stop neck lump clinic: phase 2 of audit. How are we doing?

One‐stop neck lump clinic: phase 2 of audit. How are we doing? Regular monitoring and audit of a service are integral to ensuring maintenance of efficiency and standards. This is particularly important where the quality of the service is operator dependent, as is the case in the clinical diagnosis of neck lumps and fine needle aspiration cytology. The one‐stop neck lump clinic has now been running in the department for more than 20 months. A previous article described the results of the first phase audit carried out at 6 months and had identified a waiting time to be seen that was longer than that recommended by the British Association of Otorhinolaryngologists, Head and Neck Surgeons. Measures were implemented to reduce this waiting time and a second audit was carried out after another 10 months with the aims of assessing if modification of the means of referral reduces waiting time and if the outcomes of clinical performance in phase 1 could be maintained or improved. We discuss the results of phase 2 in the audit spiral.     

Physiologische Grundlagen einer Hörprothese

Zusammenfassung Im Bemühen, eine Hörprothese zu entwickeln, die ein Sprachverständnis erlaubt, erscheint es zumindest fürs erste am zweckmäßigsten, durch künstliche elektrische Reizung des Hörnerven die natürlichen Verhältnissen so gut als möglich zu imitieren. Der normale Hörnerv enthält etwa 30000 Nervenfasern, die sich qualitativ gleich, quantitativ jedoch unterschiedlich verhalten, wobei über die Eigenschaften der von den ÄHZ kommenden Spiralfasern im Augenblick sichere Aussagen nicht möglich sind (siehe 2.3). Die quantitativen Unterschiede zwischen den einzelnen Hörnervenfasern beziehen sich auf deren Frequenzabstimmung, Frequenzselektivität, Schwellen, Intensitätsfunktionen und — wichtig insbesondere für das Vorhaben einer künstlichen elektrischen Reizung — in Zeitunterschieden in den Aktivitätsmustern, die durch Laufzeitunterschiede auf der Basilarmembran bedingt sind (2.3). Diese Zeitunterschiede in der Aktivität einzelner Fasern liegen im Bereich mehrerer ms (2.3.6; 2.3.7). Die durch Schallreize im normalen Hörnerven ausgelösten Aktionspotentiale haben überdies einen probabilistischen Charakter, d. h. ihr Auftreten ist keineswegs streng determiniert. Es versteht sich von selbst, daß man bei künstlicher, elektrischer Reizung nicht alle verbliebenen Nervenfasern selektiv reizen kann. Somit wird eine Reizelektrode immer eine Gruppe von Nervenfasern erregen müssen. Bei jeder denkbaren elektrischen Reizung wären alle Fasern im Reizbereich einer Elektrode synchron und streng deterministisch aktiviert, was einen außerordentlich ernstzunehmenden Unterschied zu natürlichen Verhältnissen darstellt (3.2).Um die Zahl der zum Sprachverständnis mindestens notwendigen Reizkanäle abzuschätzen, wird man, in Ermangelung anderer experimenteller Daten, von psychoakustischen Untersuchungen an Normalhörenden auszugehen haben. Diese haben gezeigt, daß das Gehör neben einer außerordentlichen Fähigkeit verschiedene Tonhöhen zu unterscheiden, andererseits die Fähigkeit besitzt, bestimmte Frequenzgebiete zu sogenannten Frequenzgruppen zu integrieren. Die in eine solche Frequenzgruppe fallende Schallenergie wird zu einem einheitlichen Höreindruck verarbeitet. Es scheint also sinnvoll, die für einen Prothesenbau notwendige Zusammenfassung von Gruppen von Fasern des Hörnerven in verschiedene Reizkanäle entsprechend diesen Frequenzgruppen vorzunehmen (3.1). Demnach müßte der Sprachbereich in 15 Reizkanäle aufgeteilt werden, was wiederum, wenn man in der Cochlea reizen will, 1,2 mm Abstand von Kanal zu Kanal erlauben würde. Dabei müßte der Reizerfolg sauber auf die einzelnen Kanäle beschränkt bleiben, d.h. eine optimale Kanaltrennung erreicht werden. In Anbetracht der groben Abweichungen der neuronalen Aktivität vom normalen Verhalten, die bei künstlicher, elektrischer Reizung unvermeidlich sind, ist freilich unsicher, ob die angegebene Zahl ausreichen würde. Andererseits ist es in Anbetracht der zu erwartenden Stromverteilung im Sprachbereich kaum vorstellbar, mehr als die angegebene Zahl von Kanälen realisieren zu können.Was die Kodierung der Schallparameter innerhalb eines Elektrodenkanals betrifft, wird vorgeschlagen, die Frequenzkodierung nach dem Ortsprinzip optimal auszunutzen, und im Hinblick auf die Periodizitätsanalyse und die Lautheitskodierung sich soweit als möglich den natürlichen Verhältnissen anzunähern (3.3). Dabei wären Laufzeitunterschiede zwischen den Kanälen und der probabilistische Charakter der neuronalen Entladungen soweit als möglich einzuführen, um die Dominanz eines periodicity pitch zu vermeiden.Eine für Sprachverständnis ausreichende Prothese ist auch nur denkbar, wenn eine Prothese die zur Sprachübertragung notwendige Übertragungskapazität besitzt. Ergebnisse der Kanal-Vocoder-Technik zeigen, daß Sprache noch mit 1500 bit/s befriedigend übertragen werden kann. Eine Abschätzung der möglichen Leistungsfähigkeit einer 15-kanaligen Prothese (3.4), basierend auf der Zahl der möglichen unterscheidbaren Unterschiedsstufen der Hörempfindung, ergibt, daß diese Übertragungskapazität knapp erreicht werden könnte. Allerdings ist damit noch nicht gesagt, daß das Zentralnervensystem die angebotene Information auch im Sinne einer Phonemanalyse auswertet und damit für ein Sprachverständnis maximal ausschöpft. Nur für diesen Fall wäre ein Sprachverständnis zu erwarten.Als Reizort erscheint in erster Linie die Cochlea (5.1) geeignet. Für den Fall einer Degeneration der primären afferenten Fasern des Hörnerven ist aufgrund physiologischer Überlegungen auch der Nucleus cochlearis ventralis (5.5) interessant, allerdings würde so nur der ventrale Anteil der Hörbahn stimuliert. Doch besitzen auch andere Reizorte spezifische Vorteile (5.2–5.4).Theoretische Überlegungen (6.1) und experimentelle Messungen an implantierten Elektrodensätzen (6.3) zeigen, daß die Forderung der Kanaltrennung nur schwer zu erreichen sein wird. Deswegen wird der dynamische Bereich (im Hinblick auf Veränderung des Reizstromes) eines nach den obigen Kriterien konstruierten Reizkanals auf maximal 3 dB zu beschränken sein, so daß Erregungsausbreitung auf weitere Bereiche der Cochlea durch Ansteuerung von mehreren Reizkanälen zu imitieren wäre.Die Chancen, eine Prothese zu verwirklichen, die befriedigendes Sprachverständnis auf der Basis einer quasinatürlichen Reizung des Hörnerven erlaubt, wird von uns in Anbetracht der geschilderten mannigfaltigen Schwierigkeiten als sehr niedrig angesehen. In Anbetracht des großen Nutzens, der andererseits eventuell resultieren könnte, halten wir die Erforschung des Problems jedoch für angebracht.Es wird von uns vorgeschlagen, auch zu untersuchen, ob sich für eine prothetische Versorgung vorverarbeitete Sprache besser eignet (7.). Für Prothesen, die ein Sprachverständnis nicht anstreben, halten wir eine Implantation in die Cochlea für überflüssig. Hier erscheint uns die Implantation von Reizelektroden am runden Fenster (Douek et al., 1977; Fourcin et al., 1978; s. a. 1. und 7.) wegen des geringeren Risikos der überlegenere Weg.Die zitierten eigenen Arbeiten der Autoren wurden mit Unterstützung der DFG durchgeführt (DFG-K1 219).     

The expression of vascular endothelial growth factor (VEGF) and VEGF‐C in early laryngeal cancer: relationship with radioresistance

The expression of vascular endothelial growth factor (VEGF) and VEGF‐C in early laryngeal cancer: relationship with radioresistance Angiogenesis is essential for tumour growth and invasion. Vascular endothelial growth factor (VEGF) is a prime mediator of tumour angiogenesis. VEGF‐C is a closely related protein that effects lymphatic endothelial cells and may be important in the process of lymphatic metastasis. The purpose of this study was to evaluate the expression of these cytokines in patients with T1 and T2a glottic, squamous cell carcinoma, in comparison with normal epithelial control tissue, to ascertain any association with radioresistance. Twenty‐two tumours treated by radiotherapy (13 radiosensitive, nine radioresistant) and seven normal control tissues were studied. The minimum follow‐up was 2 years after radiotherapy. Expression of VEGF and VEGF‐C was evaluated by immunohistochemistry of formalin‐fixed, paraffin‐embedded biopsy specimens. Analysis was carried out using a quantitative computer image analyser. Both VEGF and VEGF‐C were detectable in tumour and normal control specimens. There was increased expression in tumour specimens of both VEGF (P = 0.03) and VEGF‐C (P < 0.001). In addition, the expression of VEGF‐C was associated with tumours of higher histological grade (P = 0.021). There was, however, no difference in VEGF and VEGF‐C expression between radioresistant and radiosensitive tumours. The expression of VEGF and VEGF‐C is increased in early laryngeal squamous cell carcinoma (SCC). However, measuring the expression of these proteins cannot predict radioresistance in this tumour group.     

Limited Surgery for Cancer of the Larynx and Hypopharynx: Options and Consequences

We reviewed surgical options for laryngeal preservation (limited surgery) in laryngeal and hypopharyngeal cancers and the consequences of the options. Of 44 patients with laryngeal cancer, 11 (25%) received limited surgery and 33 (75%) received total laryngectomy. The survival rates were 91% for the limited surgery group and 73% for the total (radical) surgery group. Of 31 patients with hypopharyngeal cancer, 7 (23%) received limited surgery and 24 (77%) received total laryngopharyngectomy. The survival rates were 53% for the limited surgery group and 40% for the total (radical) surgery group. The survival rates associated with limited surgery were thus better than those for total (radical) surgery for cancers of both the larynx and hypopharynx. This was attributed to the limited surgery group comprising well-selected patients with confined lesions. Organ preservation surgery should be technically simple, reliable in terms of its functional impact and, above all, should not jeopardize the patient's survival. Supracricoid subtotal laryngectomy with cricohyoidoepiglottopexy or cricohyoido-pexy has great potential for laryngeal preservation and will become the major limited surgery modality for treating cancer of the larynx. Limited surgery, however, needs to be performed with great care and is indicated only for very well-selected patients with cancer of the hypopharynx.     

Treatment of Maxillary Sinus Carcinoma: Clinical Results Using the Kitasato Modality

The conventional therapeutic regimen for maxillary sinus carcinoma consists of dissection of the maxilla, full-dose irradiation and extensive chemotherapy. However, the results obtained with this treatment are often poor. Even when patients recover, their quality of life is significantly reduced as a result of deformity of facial structures and swallowing and articulation dysfunctions. A retrospective analysis of 68 patients with maxillary sinus carcinoma treated with the Kitasato modality between 1975 and 1999 was conducted. All patients underwent pergingival maxillary sinus surgery combined with pre- and postoperative irradiation therapy with standardized total doses of 16 Gy; the postoperative irradiation was given in combination with regional intra-arterial infusion chemotherapy administered via the superficial temporal artery. All visible tumor lesions were removed where possible in order to preserve or facilitate cellular immunity after surgery. The cumulative 5-year survival rates were 85.7% for Stage II patients, 88.1% for Stage III, 76.6% for Stage IVA and 75.0% for Stage IVB.     

Cervical Reflex Induced by Click Stimuli in Cats

We studied click-evoked potentials in the anterior horn of the spinal cord in 17 cats. A concentric needle electrode was inserted into the anterior horn of the spinal cord at levels C3-C6. Potentials evoked with 105 dB SPL clicks were recorded with a peak latency of 4.89-5.10 ms only at the C3 level. These responses were observed 45-60 dB SPL above the auditory brainstem response (ABR) threshold, and no potentials were evoked by stimulation of the contralateral ear. Average was performed 100 times with changes in stimulation frequency of 1-20 Hz. The amplitude of the potentials decreased with increasing stimulus frequency, but there were no changes in ABRs. The responses disappeared after destruction of the medial vestibulospinal tract at the obex level, but ABRs were still recorded. The spinal nucleus of the accessory nerves was located in the anterior horn of the spinal cord at levels C1-C6, and the sternocleidomastoid muscle motoneurons were found at levels C1-C3. The click-evoked potentials recorded in this study reflect responses of the spinal nucleus of accessory nerves through the vestibulospinal tract to click stimulation. The responses have the same characteristics as vestibular-evoked myogenic potentials that can be recorded using surface electrodes over the sternocleidomastoid muscles of humans.     

A simple objective evaluation and grading for facial paralysis outcomes

Matrix metalloproteinase (MMP)-2 and -9 degrade type IV collagen, which is one of the major components of the basement membrane in normal tissue and expressed in the surroundings of the cancer nest in squamous cell carinoma. The degeneration of type IV collagen is an essential step in the metastasis to lymph nodes and distant organs. In this study, we examined MMP-2 and -9 levels of cancer tissue and serum obtained from patients with head and neck squamous cell carcinoma (HNSCC) in order to evaluate the relationship between the clinicopathologic features and MMPs. We examined the production of MMP-2 and -9 in cancer tissue homogenates of 73 patients who had HNSCC and the serum MMP levels of 16 patients with HNSCC and 8 healthy volunteers. We also studied the localization of MMP-2 in the carcinoma using an immunohistochemical approach. The concentrations of MMP-2 and -9 in the tissue homogenates and serum were measured by means of a sandwich enzyme immunoassay using a monoclonal antibody. Immunohistochemical analyses were performed with monoclonal antibody to MMP-2. The concentration of MMP-2 in the tumor tissue homogenates was unrelated to tumor size, but that in patients with lymph node metastases was significantly higher than in those without lymph node metastases. The concentration of MMP-9 was unrelated to lymph node metastasis and tumor size. The levels of both MMP-2 and -9 in serum were unrelated to lymph node metastasis. Immunohistochemistry indicated that MMP-2 was mainly expressed in cancer cells. Because MMP-2 degrades type IV collagen, the level of MMP-2 in carcinomas may be a useful indicator of the degree of invasion and metastasis.     

A case of cortical deafness and anarthria

The nasal epithelium protects the underlying tissue from damage. Epithelial cell growth is controlled by epidermal growth factor (EGF) and is possibly affected by toxic proteins, e.g. eosinophil cationic protein (ECP). The aims of this study were to examine nasal fluid epithelial cell counts and their relations to EGF, eosinophils and ECP in 23 patients with seasonal allergic rhinitis and 20 healthy controls. Nasal fluid epithelial cell counts were lower in patients than in controls. EGF levels did not differ between patients and controls, and correlated with epithelial cell counts in controls but not in patients. Eosinophils and ECP were higher in patients than in controls, but did not correlate with epithelial cell counts. The role of growth factors, such as EGF, in regulating epithelial cells merits further study.     

Tongue Base Reduction with Temperature-controlled Radiofrequency Volumetric Tissue Reduction for Treatment of Obstructive Sleep Apnea Syndrome

In recent years a considerable effort has been made to establish the use of different surgical techniques for the treatment of obstructive sleep apnea syndrome (OSAS). Nevertheless, treatment of hypopharyngeal obstruction due to tongue base hypertrophy remains in many ways an unsolved problem. The aim of this study was to evaluate the safety and efficacy of tongue base reduction with temperature-controlled radiofrequency volumetric tissue reduction in the treatment of OSAS. Twenty patients with OSAS and tongue base hypertrophy were treated with radiofrequency tissue ablation. An intensified treatment protocol was used, delivering 2,800 J per treatment session under local anesthesia. Two nights of polysomnography testing were performed before and after treatment. Daytime sleepiness, snoring and postoperative morbidity were assessed using questionnaires. Mean respiratory disturbance index (RDI) was reduced from 32.1 to 24.9/h after a mean of 3.4 treatment sessions. Six patients (33%) were cured after the procedure (reduction in RDI of &#83 50% and a postoperative RDI of <15/h) and ten (55%) showed an improvement of >20% in their RDI. Daytime sleepiness and snoring improved significantly. Peri- and postoperative morbidity was low; one severe complication occurred (tongue base abscess). We were able to achieve similar cure and responder rates to those reported in a recently published pilot study but with a reduced number of treatment sessions. We believe that this technique may improve patient acceptance and have beneficial cost implications.