Raffaello D'Amico

Vestibular evoked myogenic potentials and glycerol testing.

Objectives/Hypothesis: The objective was to evaluate dizziness as the first symptom of endolymphatic hydrops, which could provide valuable information on the initial stages of endolymphatic hydrops development.

Vestibular Evoked Myogenic Potentials and Distortion-Product Otoacoustic Emissions Combined with Glycerol Testing in Endolymphatic Hydrops: Their Value in Early Diagnosis

The present investigation was specifically designed to evaluate the ability of the glycerol test combined with pure tone audiometry, distortion-product otoacoustic emissions (DPOAEs), and vestibular evoked myogenic potentials (VEMPs) to diagnose endolymphatic hydrops early and to identify cases that may evolve toward Menieres disease. This investigation consisted of 29 consecutive patients with mild dizziness or vertigo who received no treatment. Each patient underwent glycerol testing measured with conventional pure tone audiometry and with both DPOAEs and VEMPs. It is interesting to note that in 7 and 8 of the 29 cases, the VEMPs and DPOAEs, respectively, showed an improvement after glycerol administration that had not been shown on traditional audiometry. A further element worthy of consideration emerges from an analysis of the VEMP results compared to the DPOAE results that divided the patients into 4 groups. The first group had a postglycerol improvement with both methods, which would seem to suggest hydrops in both the anterior and posterior parts of the labyrinth. In the second and third groups, there was an improvement only either with VEMPs or DPOAEs, and this finding seems to indicate that only one endolymphatic compartment might be involved. In the last group, all patients had a positive glycerol test with positive DPOAEs on one side and with positive VEMPs on the other. Although endolymphatic hydrops can only be proven after death, a combination of VEMPs and DPOAEs with the glycerol test may permit early diagnosis of endolymphatic hydrops. These results clearly imply that these methods should be permanently included in the diagnostic protocol of patients with vestibular and audiological symptoms.

Results and complications of facial reanimation following cerebellopontine angle surgery.

Abstract The present study was undertaken to evaluate the results of a group of patients following treatment for cerebellopontine angle lesions who developed postoperative facial palsy and underwent facial nerve repair in order to reanimate the muscles of facial expression. A retrospective study was performed on 23 patients treated between 1988 and 1997 at the 2nd and 4th ENT chairs of University “La Sapienza” of Rome for facial palsy following cerebellopontine angle surgery. Tumors included acoustic neuromas (n = 3). Seventeen patients underwent hypoglossal-facial anastomoses [10 with end-to-end anastomoses, 4 with May’s interposition “jump-nerve” grafts and 3 with partial (30%) use of the hypoglossal nerve plus a facial cross-over]. The remaining patients were operated on using a cable graft with the sural nerve (n = 2) and the great auricular nerve (n = 4). Postoperative facial function was determined by the House-Brackmann 6-scale classification The hypoglossal-facial anastomoses resulted in long-term grade III or IV findings. Cable grafts improved facial function from grade VI to grade III. None of the patients operated on with the modfied VII-XII anastomosis developed swallowing disturbances. The ten patients having traditional hypoglossal-facial anastomoses showed different degrees of tongue disability and retention of residue in the oral cavity. Surgical recovery of postoperative facial palsy can be obtained with various techniques according to the availability of the proximal facial nerve stump at the brain stem. Since a traditional hypoglossal-facial anastomosis procedure can be a source of a separate disability for the patient, techniques are preferred that leave the hypoglossal nerve mostly intact and uncompromised.

Preservation of the saccular nerve and of the Vestibular evoked myogenic potential during vestibular schwannoma surgery

Objective The aim of the study was to present a case report demonstrating that vestibular evoked myogenic potentials originate from the saccular nerve. Study Design Retrospective case review. Setting Tertiary referral center. Intervention Vestibular evoked myogenic potentials are shown before and after operation in a patient with a surgically confirmed superior vestibular schwannoma (1.3 cm). Main Outcome Measures Preoperative and postoperative audiometry, auditory brainstem response, caloric test, vestibular evoked myogenic potentials, and magnetic resonance imaging outcomes. Results On preoperative audiometry, slight sensorineural hearing loss with normal auditory brainstem response could be detected. Caloric tests showed a reduced response of the right labyrinth. Vestibular evoked myogenic potentials were normal. The tumor was removed via a combined retrosigmoid and partial labyrinthectomy approach with the removal of the posterior semicircular canal. The facial, auditory, and inferior semicircular nerves were anatomically preserved. Postoperative audiometry revealed preservation of hearing and vestibular evoked myogenic potentials; caloric responses were now absent. Conclusion The combined retrosigmoid and partial labyrinthectomy approach represents an ideal condition to study the influence of the saccular nerve on the origin of the vestibular evoked myogenic potentials. The maintenance of the vestibular evoked myogenic potential responses in our patient supports the concept that the vestibular evoked myogenic potential originates in the saccule and is transmitted in the saccular nerve.

Delayed facial palsy after vestibular schwannoma resection: Clinical data and prognosis

PURPOSE The object of the present study was to review a series of surgically removed vestibular schwannoma tumours to establish the incidence of delayed facial palsy and to evaluate the course of recovery according to the possible etiology (surgical postoperative edema or viral reactivation) with reference to the time of onset. MATERIALS AND METHODS The study group was composed of 98 patients with vestibular schwannoma. Sex, age, location, and extent of tumour and postoperative complications were all taken into consideration in the final evaluation. The course of each patients postoperative facial function was graded according to House and Brackmanns six-grade scale. The incidence and the time of onset of the delayed facial palsy were also evaluated. RESULTS The deterioration in the facial function was found to be delayed in 25 of the 98 patients (26%); of these, it occurred in the first 5 days after surgery in 11 cases, between 6 and 13 days in 10 cases, and after 15 days in 14 patients. The incidence rate of the delayed facial dysfunction was not influenced by age, sex, or the size of the tumour. The prognosis of the facial dysfunction was favourable in the majority of cases, and, in fact, there were only five grade III to IV cases 1 year later. Facial dysfunction was over grade III in the majority of the latter five cases, and the period of recovery was long. CONCLUSIONS Eighty percent of our patients with delayed facial palsy following vestibular schwannoma resection were classified as having excellent or good function. In the remaining patients who had a less favourable recovery, the palsy was more severe, and the onset occurred after some time. This seems to agree with those who are of the opinion that the complication is due to viral reactivation. In these patients, it is advisable to start aggressive medical therapy with antiviral agents such as acyclovir as soon as possible.

Distortion-product otoacoustic emissions and glycerol testing in endolymphatic hydrops

Objectives/Hypothesis Aural fullness is a frequent symptom of endolymphatic hydrops. Its evaluation may provide valuable information on the initial stage of development of endolymphatic hydrops.

Human aural myiasis.

ment for evaluation and treatment of left aural myiasis. Seven days earlier she had reported sensing an itch in her left external auditory canal. This symptom was associated with intermittent severe pain. Clinical examination revealed a bloodtinged aural discharge. Through otomicroscopy, numerous animate maggots were seen (Fig 1). They were carefully removed with microsurgical forceps under an operative microscope. This maneuver was facilitated by application of the suction tip to their bodies (Fig 2). After mechanical removal of the maggots, the patient’s symptoms were completely relieved. The skin of the affected ear canal looked normal, and no abnormality involving the tympanic membrane was detected. The larvae were identified as Sarcophaga hemorrhoidalis. Several weeks later the patient was disease free. Aural myiasis is rare1-3 and occurs most often in children younger than 10 years because of their low level of personal hygiene. Infestation can also occur in adults, especially those who are mentally retarded, as was observed in our patient. Aural myiasis develops from fly maggots, the eggs of which are laid in meat, cheese, fish, or feces. Many families of flies (Calliphoridae, Sarcophagidae, Gastrofilidae, Cuterebridae, Musca, Famina, Chrysomyia, Calliphoridae vicius, Calliphoridae americanae) have been identified. Sood et al3 reported that the Sarcophagidae are the most commonly encountered. Most infestation occurs in developing countries; however, the prevalence has decreased over the years, and currently it is very rare. Diagnosis is easy through otomicroscopy, which reveals the presence of larvae. Initial presentation exhibits different clinical symptoms including ear pain, purulent or bloodtinged aural discharge, vertigo, and/or tinnitus. Usually the external ear canal shows granulation and/or debris associated in many instances with perforation of the tympanic membrane.2 It is interesting to mention that the maggots can inhabit a normal ear, as reported by Cosgrove4 and as observed in our case. The treatment of choice is still debated and includes use of different materials: chloroform, oil drops, urea, dextrose, creatine, hypertonic saline, and iodine solution.2 Whatever substances are used, however, it is essential to mechanically remove the larvae. This must be followed by antibiotic therapy to avoid secondary infection.

Reconstruction of old radical cavities and long-term results.

Various techniques and materials have been proposed to deal with the problems that concern radical cavities, such as recurrence of the inflammatory process, the need for regular medication, and social inconvenience (eg, inability to practice water sports, working in an adverse enviroment). This article provides a detailed report of the results of revalidation of old radical cavities using hydroxyapatite granules as a filling. The material was incorporated with fibrin adhesive to fill the mastoid cavity and was covered with a sheet of bone pate sealant. Twenty-eight patients with chronic discharging old radical cavities were selected for this study (mean follow-up 11.4 years; range 10-14 years). At the 6-month follow-up, grafting was successful in 25 patients, whereas the functional outcomes showed an air-bone gap below 30 dB in 18 patients. No postoperative sensorineural hearing loss was observed. The long-term follow-up demonstrated a slight worsening of the initial findings; four other patients had reperforation of the tympanic membrane, and hearing deteriorated in five patients to above 30 dB air-bone gap. These results could be a consequence of an alteration in the function of the eustachian tube and of the severity of the preoperative pathologic processes.

Multiple familial facial glomus: Case report and review of the literature

Facial paraganglioma is an extremely rare tumor that originates from abnormal paraganglionic tissue situated in the intrapetrous facial canal. A review of the English-language literature shows that only 8 cases of facial nerve paraganglioma have been published. In each case the facial glomus presented itself sporadically, completely independent of any other form of paraganglioma. This study reports an intrapetrous facial glomus that occurred in a case of multiple paragangliomas with a hereditary pattern. To our knowledge, this is the first report of such a combination.

Facial Reanimation: A Proposal to Reduce Postoperative Morbidity

INTRODUCTION In postoperative facial palsy during cerebellopontine angle surgery, end-to-end hypoglossal–facial nerve anastomosis is at present the most popular technique used in rehabilitation of facial function in cases with loss of the proximal stump of the facial nerve. However, this technique may be a source of additional morbidity such as swallowing or speech dysfunction because facial expression is recovered at the expense of glossal function. Other potential complications may be excessive facial muscle tone, spasms, and synkinesis. Several alternative techniques have been proposed to eliminate these disabilities caused by erroneous nerve regeneration processes. May et al., Terzis, Arai et al., Cusimano and Sekkar, Atlas and Lowinger, and Sawamura and Hiroshi have reported successful results with their techniques in preserving glossal function. May et al. suggested grafting of the great auricular nerve between the facial nerve and a partially incised hypoglossal nerve. Function of the tongue is well preserved using this method, but the face does not respond equally positively and the rehabilitation period is longer, probably as a result of a pronounced fibrosis caused by multiple anastomoses and by the need for jumping the grafted nerve. Other authors have preferred the “split hypoglossal-facial nerve anastomosis” technique, but this invariably implies that the axons of the seventh cranial nerve could be transected at various levels because anatomically the hypoglossal nerve is not multifasciculated and therefore cannot be subdivided into fascicles. This may cause varying degrees of hemiglossal atrophy. Atlas and Lowinger and Sawamura and Hiroshi contemporaneously presented an alternative technique of hypoglossal–facial nerve surgery that involves end-to-side facial–hypoglossal nerve anastomosis. This is performed by skeletonizing the facial nerve in the mastoid and tympanic segments and transposing it from the fallopian canal to the hypoglossal nerve. This method is particularly advantageous because it requires only one nervous anastomosis, ensuring a better preservation of tongue function. No matter which technique of hypoglossal–facial nerve anastomosis one decides to adopt, optimal facial function is regained as far as muscular tone is concerned, but symmetrical coordination of the facial expression is unsatisfactory. To overcome this problem, Terzis devised the “baby-sitter” technique that combines hypoglossal– facial nerve anastomosis and facial crossover technique. The latter of these, on its own, does not always produce a sufficient muscular tone to ensure valid contraction, even if it does permit a good recovery of the dynamic symmetry of the face. The “baby-sitter” technique combines the two methods of facial rehabilitation, preserving the respective advantages and eliminating the disadvantages. However, the twelfth–seventh nerve technique employed (split hypoglossal–facial nerve anastomosis) is, as stated previously, a questionable method as far as tongue function is concerned. The aim of the present report is to present a modification of the classic baby-sitter technique, substituting split hypoglossal–facial nerve anastomosis with the method proposed by Atlas and Lowinger in an attempt to reduce its potential morbidity.