一侧膈神经上根选择性神经再支配环杓后肌的实验研究

目的 探讨一侧膈神经上根选择性神经再支配环杓后肌的可行性和有效性.方法 8只健康雄性青年Beagle犬作为实验动物,全麻下切断Beagle犬左侧膈神经上根与左侧喉返神经,两断端通过游离神经桥接的方式吻合,并将同侧喉返神经内收肌支切断并植入同侧环杓后肌中;右侧不做任何处理,作为正常对照侧.于手术前、神经修复术后即刻、术后6个月分别行电子喉镜和喉肌电图检查,在最后一次检查后处死动物,取双侧环杓后肌和喉内段喉返神经行组织学检查并与对侧比较.结果 术前8只犬的双侧声带运动正常,术后即刻左侧声带固定,术后6个月均恢复了吸气性外展运动.术前8只犬双侧环杓后肌均能记录到自发肌电位,并引出诱发电位;术后即刻左侧环杓后肌呈电静息,未记录到诱发电位;术后6个月均能记录到自发肌电位,并引出诱发电位,而且两种电位幅度分别与术前比较差异均无统计学意义(均为P>0.05).环杓后肌Masson染色示两侧肌肉纤维相对截面积、胶原纤维相对截面积、肌肉/胶原纤维截面积比差异均无统计学意义(均为P>0.05).喉内段喉返神经甲苯胺蓝染色后示神经纤维分布较均匀密集,且左右两侧喉返神经有髓神经纤维数量差异无统计学意义(P>0.05).结论 左侧膈神经上根选择性神经再支配环杓后肌能有效避免神经错向再生,恢复声带的生理性外展运动.     

Retrolabyrinthine vestibular neurectomy: a reevaluation

Selective vestibular neurectomy is considered an effective means of relieving intractable vertigo while preserving hearing. In order to determine the effectiveness of the retrolabyrinthine approach to selective vestibular neurectomy, we evaluated 161 patients who underwent vestibular neurectomy between April 1981 and September 1985. Questionnaire responses indicated that 97% of the Meniere's disease patients and 68% of the non-Meniere's disease patients experienced a substantial improvement or resolution of their vertiginous symptoms. Hearing was maintained within 10 dB of the preoperative level in the majority of the patients. Neurological complications were limited to 2 cases of meningitis which resolved with medical therapy, 7 cases of cerebral spinal fluid leaks, and 3 cases of complete sensorineural hearing loss. Based on this review, we concluded that retrolabyrinthine vestibular neurectomy continues to be a safe and effective approach to relieve ear-related vertigo.     

Retrolabyrinthine surgery: anatomy and pathology

Retrolabyrinthine surgery is done to expose the cerebellopontine angle directly through the ear. It is indicated when the hearing in the ear to be operated upon is useful. The surgical technique entails four steps: complete mastoidectomy, extended posterior exposure of the sigmoid sinus, exposure of the posterior fossa dura, and exposure of the cerebellopontine angle. Retrolabyrinthine exposure of the cerebellopontine angle is indicated in tic douloureux, atypical facial pain, and hemifacial spasm. Recently, this approach has been used for sectioning the vestibular nerve, exploration of the posterior fossa to obtain a diagnosis, subtotal resection of large cerebellopontine angle tumors, and for the treatment of other cranial nerve problems. The histopathologic findings in the temporal bones of two patients who underwent retrolabyrinthine removal of cerebellopontine angle masses were reviewed. In one, subtotal resection of an acoustic tumor was attempted to preserve hearing in the presence of a bilateral tumor, with no adverse effect on the middle or inner ear. In the second, retrolabyrinthine exploration of the cerebellopontine angle was done for primary cholesteatoma, and operative injury to the nonampullated end of the posterior semicircular canal was noted. Retrolabyrinthine subtotal resection of large acoustic tumors is advocated in bilateral cases and in elderly persons to delay the inevitable loss of hearing by decompression and partial removal of the tumor mass. In primary cholesteatoma of the cerebellopontine exploration may be indicated to obtain a definitive diagnosis before surgical extirpation of the disease is planned.     

Retrolabyrinthine approach: Technique and newer indications

Excellent exposure of the cerebellopontine angle is obtained by an approach through the mastoid posterior to the labyrinth. Since the major portion of the dissection is extradural, this approach is associated with a very low morbidity. The retrolabyrinthine approach has been used for several years for selective partial section of the posterior root of the trigeminal nerve in cases of trigeminal neuralgia. Complete relief of pain has been accomplished in 25 of 28 cases, and the other 3 patients had partial relief of pain. The only complications in these patients were partial hearing impairment in 2, and 1 partial abducens nerve paralysis which subsequently recovered completely. Two patients required secondary closure of cerebrospinal fluid leaks. This approach has also been used for exploration and biopsy of cerebellopontine angle tumors and for treatment of other cranial nerve problems. We conclude that the retrolabyrinthine approach is the preferred route to the cerebellopontine angle in a variety of clinical conditions.     

Retrolabyrinthine or retrosigmoid vestibular neurectomy: indications

Selective vestibular nerve section is indicated for the treatment of vertigo in unilateral Meniere's disease or other inner ear disorders, in patients with salvageable hearing. Since 1978, the retrolabyrinthine approach to the vestibular nerve in the cerebellopontine angle has been used extensively with good success and minimal morbidity. In an attempt to obtain more complete section of the vestibular nerve, the retrosigmoid-internal auditory canal approach was developed in 1985 and has been employed in 13 patients, all of whom obtained complete control of vertigo. The surgical techniques are presented with emphasis on the advantages and disadvantages of each approach. Relative indications and contraindications are suggested.     

Retrolabyrinthine vestibular nerve section: analysis of results

The retrolabyrinthine section of the vestibular nerve is an effective procedure for the ablation of unilateral vestibular function while preserving hearing. Although this procedure has been most frequently used for the control of unilateral Meniere's disease, it may also be effective in the control of unilateral vestibular dysfunction of other etiologies. A 2-year experience with the indications for and the surgical results in a series of patients who underwent this procedure is presented. Brief case histories of a variety of etiologies of unilateral vestibular dysfunction are discussed.     

Retrolabyrinthine vestibular nerve section: evaluation of technical modification in 143 cases.

Selective vestibular nerve section is effective in relieving intractable vertigo while preserving hearing. Histologic study demonstrated overlap of the cochlear and vestibular fibers at the cochleovestibular cleavage plane within the posterior fossa. In the hopes of improving surgical results by sectioning these overlapping vestibular fibers, the technique of sectioning the vestibular division of the eighth nerve was modified to include a small portion of the cochlear division. We have evaluated 143 cases of retrolabyrinthine vestibular nerve section in which this technical modification was employed. A patient questionnaire was used to examine control of vertigo as well as changes in tinnitus, unsteadiness, and disability. Hearing preservation and incidence of complications were also reviewed. Resolution or improvement of vertigo occurred in 93 percent of Menièré's cases and 74 percent of non-Menièré's cases as compared to 97 percent and 68 percent, respectively, in the pre-1986 series.     

Retrolabyrinthine vestibular nerve section: efficacy in disorders other than Menière's disease

The retrolabyrinthine vestibular nerve section has evolved as an effective treatment for intractable vertigo of peripheral vestibular origin when hearing preservation is desired. This report studies the efficacy of retrolabyrinthine vestibular nerve section for control of vertigo due to causes other than Meniere's disease. This report details our experience with 42 patients with a wide variety of diagnoses. The reduced success rate of retrolabyrinthine vestibular nerve section in these patients is difficult to evaluate, as very few patients have been analyzed with respect to their specific diagnoses. Of patients who underwent retrolabyrinthine vestibular nerve section for control of vertigo, 23 patients had uncompensated vestibular neuritis and 19 others had a wide range of other diagnoses. For patients with uncompensated vestibular neuritis (n = 23), the physician record noted that 39% of patients were cured and 30% improved. This compares to our series of patients with Meniere's disease (n = 48), where 94% were cured and 2% improved. The true vestibular abnormality may be less reliably identified in patients with uncompensated vestibular neuritis, contributing to the less effective results. Since the development of a vestibular rehabilitation program, retrolabyrinthine vestibular nerve section for uncompensated vestibular neuritis has been all but abandoned. Retrolabyrinthine vestibular nerve section appears to achieve a high cure rate in patients with sensorineural hearing loss associated with their vestibular abnormalities. While retrolabyrinthine vestibular nerve section is helpful for control of vertigo in some diagnoses, a substantial incidence of persistent postoperative dysequilibrium was noted.     

Posterior ankyloglossia: A case report

Ankyloglossia, or tongue-tie, refers to an abnormally short lingual frenulum. Ankyloglossia is a recognized but poorly defined condition and has been reported to cause feeding difficulties, dysarthria, dyspnea, and social or mechanical problems. In infants, the most concerning symptoms are feeding difficulties and inability to breastfeed. While a recent trend toward breastfeeding has brought frenulectomy back into favor, the literature regarding treatment remains inconclusive. We report a case of posterior ankyloglossia with anterior mucosal hooding and a simple, safe, and effective way to treat it to improve breastfeeding.     

Posterior choanal atresia: a syndromal disorder

Posterior choanal atresia has a significant incidence of associated defects. Recently a constellation of defects, bearing the acronym of CHARGE, has been described. Its entities are (ocular) Coloboma, Heart defects, Atresia choanae, Retarded growth and development, Genital hypoplasia and Ear anomalies or hearing loss. Some of these have been previously noted. There are 26 patients in this series, none having the entire CHARGE association, but 7 had several; 3 of the 7 had bilateral choanal atresia. One other patient had a chromosomal defect with an associated heart defect. Two patients had cardiac and other visceral defects. Seven had base of skull abnormalities, 3 of whom had elements of CHARGE, and 9 had congenital hearing loss. Five were normal. CT scan suggests a growth disturbance of the basicranium in some of the patients.     

Posterior epistaxis: identification of common bleeding sites

OBJECTIVE: The objective of this study was to determine common bleeding sites in the nasal cavity of patients with posterior epistaxis and thus review our management protocol. STUDY DESIGN: A prospective study was carried out from 1989 to November 2003 in the otolaryngology-head and neck surgery department of a tertiary referral center. This study included patients who presented with posterior epistaxis uncontrolled with standard nasal packing and with no identifiable bleeding point on examination under local anesthesia. METHOD: All patients underwent a formal examination under general anesthesia by the senior author of this article. Findings at examination were documented along with subsequent management and its outcome. RESULTS: Forty-three patients were included in this study. Bleeding points were identified in 36 cases. Seven patients had septal bleeding points (20%). The rest were located on the lateral nasal wall (81%). Of these, 4 were on the lateral wall of inferior meatus, 7 on the lateral surface of inferior turbinate, 8 on the lateral wall of middle meatus, and 10 on the lateral surface of middle turbinate. All were located posteriorly. CONCLUSIONS: We recommend examination under general anesthesia when conservative measures fail to control bleeding, concentrating on the posterior aspect of the lateral nasal wall. In addition, the lateral aspect of the middle and inferior turbinates may contain a groove within which bleeding points may be concealed. The lateral position of most bleeding sites indicates that use of nasal packing can only attempt to indirectly tamponade blood flow and is rarely justified bilaterally. Electrothermocautery can achieve excellent results with minimal complications. Failure to identify a bleeding point, after thorough examination under general anesthesia, does not require further intervention unless complicated by further bleeding.     

Posterior glottic diastasis: mechanically deceptive and often overlooked

Dysphonia secondary to posterior glottic aerodynamic incompetence can often be recognizable acoustically, but difficult to document visually. This mechanical impairment in posterior glottic closure is the result of injury caused by airway instrumentation. The difficulty of recognition of this entity is due to posterior supraglottic soft tissue that obscures the complete view during posterior glottic adduction, the lack of a structural organization of the cricoarytenoid region injury that leads to this disorder, and the lack of nomenclature. A retrospective assessment was done on 3 patients who underwent surgical reconstruction to correct posterior phonatory incompetence subsequent to laryngotracheal intubation. All 3 had sustained an injury to the cricoarytenoid joints, and 2 of the 3 had undergone paraglottic space medialization laryngoplasty that failed to solve the posterior glottic insufficiency. New procedures were designed and performed in these patients to correct the posterior glottic incompetence and are described: laryngofissure and partial posterior cricoid resection, endoscopic pharyngoepiglottic-aryepiglottic fold advancement-rotation flap with interarytenoid interposition, and interarytenoid submucosal implant augmentation. Although the academic literature is replete with reports describing stenosis resulting from impaired cricoarytenoid joint abduction, the term glottic diastasis provides nomenclature for the inability to normally adduct the arytenoid cartilages. The initial experience with surgical reconstruction is preliminary, but encouraging.     

Posterior tracheal laceration: A rare complication of tracheostomy

Tracheostomy is an operation with a long history and many potential complications. Two case reports of acute posterior tracheal wall laceration, a rare complication, are presented. Although previously described as being secondary to inadvertent knife contact with the posterior tracheal wall, both of these cases are thought to be due to insertion of the tube with excessive force against tissue made friable by previous radiation. The diagnosis should be suspected if poor ventilation follows insertion of an endotracheal or tracheal tube. The offending tube should be removed and an oral endotracheal tube inserted. After treatment of any accompanying pneumothorax, the site should be evaluated under direct vision as the endotracheal tube is withdrawn proximal to the tracheotomy. If a tear is found, esophagoscopy is performed to insure the integrity of the esophagus. Repair of the tracheal wall is done with a single layer closure through the tracheotomy alternating suturing with ventilation. A generous tracheotomy, soft tubes and care in insertion of tubes into the trachea are suggested preventive measures.     

Vestibular Nerve Section: Long-term Follow-up

Vestibular nerve section is considered an effective modality in the treatment of refractory and incapacitating vertigo. Typically nerve section results are described on the basis of short-term follow-up. We have reviewed 41 cases of vestibular nerve section spanning an 18-year period. Although the majority of cases involved classic Meniere's disease, delayed endolymphatic hydrops, vestibular neuritis, and Meniere's syndrome secondary to head trauma were also included. Surgical approaches included translabyrinthine (20 cases), retrolabyrinthine (14 cases), retrosigmoid (six cases), and middle fossa (one case) procedures. Postoperative follow-up time averaged 102 months, with 46% of patients followed for a minimum of 9 years. Results are reported according to standards set forth by the American Academy of Otolaryngology-Head and Neck Surgery. Vertigo was cured or markedly improved in 88% of cases (90% in patients with Meniere's disease) at 18 to 24 months postoperatively. These vertigo results were sustained at the time of latest follow-up. Functional level was also preserved over time despite the development of bilateral symptoms in several cases. The rate of bilateral disease reached 22% of cases. Although vertigo results remained stable, long-term follow-up of successful hearing preservation cases demonstrated deterioration over time. Postoperative continuation of medical treatment is urged to optimize and sustain the vestibular neurectomy result.     

Trigeminal sensitization and desensitization in the nasal cavity: a study of cross interactions

Chemical irritation in the human nasal cavity is poorly documented. In this field, an important issue concerns the differential responses produced by successive stimulation. Repeated identical chemical irritant stimuli can produce increases or decreases in responses (two phenomena known as self-sensitization or self-desensitization). In the same way, different molecules can interact and produce cross-sensitization or cross-desensitization. The aim of this study was to contribute to this question using two specific molecules, acetic acid (AA) and allyl isothiocyanate (AIC). As the self-sensitization and -desensitization for AIC is known, a first experiment in the present work investigated the response, acute effects and time course of sensitization or desensitization to acetic acid. A second experiment tested the responses of acetic acid after a previous stimulation with allyl isothiocyanate (mustard oil) and inversely with a short inter-stimulus interval (ISI of 45 s). A third experiment similar to the second used a long inter-stimulus interval (ISI of 3 min 30). Twelve healthy subjects participated in the study using psychophysical (intensity ratings) and psychophysiological (skin conductance response) measurements. Firstly, the results showed that repeated nasal stimulation with acetic acid produced a self-desensitization whatever the ISI. Secondly, the results showed a cross-desensitization of allyl isothiocyanate by previous acetic acid stimulation. In contrast, previous stimulation with allyl isothiocyanate had no effect on the following acetic acid response. These findings confirm that trigeminal sensitization and desensitization in the nasal cavity do not follow the same processes in relation to molecules used.     

Penetrating neck wounds: Selective exploration.

This study of 223 patients with penetrating neck wounds justifies individualizing surgical treatment. Twenty-four percent was selected for neck surgery. In spite of selective rather than mandatory neck exploration, the mortality rate related to the neck wound in this series was three percent. This compared favorably with the experience of others employing mandatory exploration. There were no deaths in our series attributable to selective observation.     

Posterior petrous face meningiomas: an algorithm for surgical management.

OBJECTIVE: The objective of the present study was to report our surgical strategy in the management of 81 patients with posterior petrous face meningiomas. STUDY DESIGN: Retrospective study. SETTING: This study was conducted at a quaternary private otology and cranial base center. PATIENTS: Of 139 patients with posterior fossa meningioma, 81 occurred on the posterior petrous face of the temporal bone and were the object of this study. INTERVENTIONS: Thirty-one patients were approached by the enlarged translabyrinthine approach. The enlarged translabyrinthine approach with transapical extension Type II was performedin 29 patients. The combined retrosigmoid-retrolabyrinthine approach was chosen in 8 cases. The modified transcochlear approach Type A with permanent posterior transposition of the facial nerve (FN) was performed in 6 patients. Two patients underwent a retrolabyrinthine subtemporal transapical approach. One patient underwent a transpetrous middle cranial fossa approach. Four patients with intracanalicular meningiomas were operated on through the enlarged middle cranial fossa approach. RESULTS: Total removal of the tumor (Simpson Grades I and II) was achieved in most patients (92.5%). The FN was anatomically preserved in 79 of the 81 (97.5%) patients. Five patients had less than 1 year follow-up, and 2 patients were lost to follow-up and were excluded in evaluation of the final FN outcome. At 1-year follow-up, 46 patients (63%) had Grade I to II, 19 (26%) had Grade III, 4 (5.4%) had Grade IV, 1 (1.3%) had Grade V, and 3 (4.1%) had Grade VI. Hearing-preserving surgery was attempted in 15 patients (18.5%) with preoperative serviceable hearing. Of these 15 patients, 11 had their hearing preserved at the same preoperative level, and 4 experienced postoperative deafness. Postoperatively, a new deficit of 1 or more of the lower cranial nerves was recorded in 3 patients. One patient experienced subcutaneous cerebrospinal fluid collection that required surgical management. CONCLUSION: Total tumor removal (Simpson Grades I-II) remains our treatment of choice and takes priority over hearing preservation. Subtotal resection is indicated for older and debilitated patients with giant lesions to relieve the tumor compression on the cerebellum and brainstem. Subtotal removal is also preferred in the face of the absence of a plane of cleavage between the tumor and the brainstem, in the presence of encasement of vital neurovascular structures, in elderly patients with tumors adherent to preoperatively normal facial or lower cranial nerves.