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Biomedical subjects

H Silverstein

Publications and source records attributed to H Silverstein.

At least 73 records · Page 4Linked to original sources
PubMed1991

Intraoperative facial nerve monitoring.

Facial nerve monitoring is one of the most exciting innovations in otologic surgery in the past decade. Intraoperative monitoring has been shown to reduce the probability of iatrogenic injury to the facial nerve during surgery. It saves surgical time and reduces the anxiety level of both patients and surgeons. There are several reasons to use facial nerve monitoring: The surgeon nerve knows when it will be needed in a particular case, the operating room personnel become familiar with the equipment, and the surgeon learns how to interpret the sounds produced by the monitor and how to correlate them with surgical manipulations around the facial nerve. Facial nerve monitoring has added another dimension of safety to otologic and neurotologic surgery and has reduced the incidence of facial weakness or paralysis in the authors' surgical practice.

Facial Nerve↗
PubMed1991

Bilateral Menière's disease in surgical versus nonsurgical patients.

In patients with Menière's disease, the possibility of developing Menière's disease in the uninvolved ear is of great concern. In this study, the incidence of bilateral Menière's disease (BMD) in medically treated patients was found to be 17 percent, while in surgically treated patients it was significantly lower, 5.9 percent (p less than 0.01). The incidence of BMD for each surgical procedure was as follows: 9 percent after endolymphatic subarachnoid shunt (n = 101), 7 percent after cochleovestibular neurectomy (n = 100), 6 percent after cochleosacculotomy (n = 18), and 0 percent after vestibular nerve section (n = 73). The average duration of disease prior to surgery was 6.3 years. Seventy-two percent of the patients who developed BMD did so within 5 years of the onset of their symptoms. Proper patient selection is the most likely explanation for the low incidence of BMD among surgically treated patients.

Adolescent↗
PubMed1990

An evolution of approach in vestibular neurectomy.

Since introducing the retrolabyrinthine vestibular neurectomy in 1978, we have performed 78 procedures with good results. In 1985 we introduced the retrosigmoid-IAC vestibular neurectomy, which allows a more complete transection of the vestibular nerves within the internal auditory canal (IAC). Vertigo control has been excellent; however, in 75% of patients, postoperative headaches have been a significant problem. In 1987, the best aspects of the two procedures were incorporated and the combined retrolab-retrosigmoid vestibular neurectomy was developed. The procedure is similar to the RVN in that all bone covering the lateral venous sinus is removed. It differs from the RVN in that a limited mastoidectomy is performed and the dura is opened just behind the LVS. The LVS is retracted forward, exposing the cerebellopontine angle. This allows the surgeon the option to section the vestibular nerve in either the CP angle or the IAC, depending upon the presence or absence of a cochieovestibular cleavage plane in the CP angle. The results have been good and the incidence of headache has been reduced to 10%. The technique, results, and complications are reported here.

Ear, Inner↗
PubMed1990

Adaptor for continuous stimulation (SACS) with the WR-S8 monitor-stimulator.

An adaptor for continuous stimulation of the facial nerve (SACS) to be used with the WR-S8 Monitor/Stimulator during otologic surgery has been developed. This device allows the surgeon to use the electrified air drill and microsurgical instruments instead of a probe-tip during dissection. The SACS saves surgical time, is easy and convenient to use, and is safe. Routine monitoring of facial nerve function using SACS has helped prevent iatrogenic facial nerve injuries and has improved our ability to save the facial nerve during otologic and neurotologic surgery.

Ear↗
PubMed1990

Wide surgical exposure for singular neurectomy in the treatment of benign positional vertigo.

Since 1972, singular neurectomy has been performed on 58 patients who had classical benign positional vertigo. The procedure is done under general anesthesia; a wide postauricular exposure is made and the external auditory canal is maximally enlarged until the vertical portion of the facial nerve is identified. This gives an excellent view of the round window niche. Our results indicate vertigo was completely cured in 80% of the cases and improved in 17%. There has been no incidence of total hearing loss in the last 49 cases and only 3 of 49 patients (6%) had sensorineural loss. Although singular neurectomy can be mastered, it will remain a procedure done by few surgeons. The wide exposure technique is safer for preservation of cochlear function and the posterior ampullary nerve is easier to find than using the transmeatal approach as described by Gacek.

Adult↗
PubMed1990

The resurrection of vestibular neurectomy: a 10-year experience with 115 cases.

Between 1925 and 1945, Walter Dandy and Kenneth McKenzie performed more than 700 posterior fossa eighth nerve sections and vestibular neurectomies to treat the intractable vertigo accompanying Ménière's disease. During the past 10 years, with the aid of microsurgical techniques and the approach to the posterior fossa through the temporal bone, vestibular neurectomy has undergone a resurgence of popularity. When hearing is to be preserved, vestibular neurectomy is the surgical treatment of choice for patients who fail to undergo a remission of the vertigo attacks of Ménière's disease. This report reviews 115 consecutive vestibular neurectomies performed from 1978 to 1988 for the treatment of Ménière's disease. In 1978, retrolabyrinthine vestibular neurectomy (RVN), a procedure in which the posterior fossa is entered anterior to the sigmoid sinus and behind the labyrinth, was introduced. During the last 3 years, the approach to the posterior fossa has been a small dural opening behind the sigmoid sinus; this approach is known as the combined retrolabyrinthine retrosigmoid approach. There have been no cases of facial paralysis and no serious complications connected with this technique. A high incidence of headache (50%) resulted when the posterior wall of the internal auditory canal was drilled away for better exposure. Transient cerebrospinal fluid (CSF) leaking occurred in 7% of the patients undergoing RVN; however, no CSF leaks occurred when the combined retrolabyrinthine retrosigmoid approach was used. In the RVN series, wound infection occurred in 20% of the cases until perioperative antibiotics reduced the rate to 3%. The results in terms of curing or improving vertigo have been excellent (94%), and hearing has been preserved to within 20 dB preoperative levels in 76% of the cases. Until a cure for Ménière's disease is found, microsurgical posterior fossa vestibular neurectomy remains the best treatment.

Cochlear Nerve↗
PubMed1989

Natural history vs. surgery for Menière's disease.

Menière's disease has an episodic course, and certain patients undergo spontaneous remission of their vertigo. A retrospective study of patients treated from 1974 to 1983 was undertaken to evaluate the long-term outcome of patients with Menière's disease for whom surgery was recommended, comparing those who had a surgical procedure with a similar group of patients who declined surgery. The surgical procedures performed were endolymphatic subarachnoid shunt (ELS), retrolabyrinthine vestibular neurectomy (RVN), middle fossa vestibular neurectomy (MFVN), and transmeatal cochleo-vestibular neurectomy (CVN). We used a questionnaire, made up according to the 1985 American Academy of Otolaryngology (AAO) criteria, for reporting results for Menière's disease treatment, and compared patients who were offered surgery but declined (N = 50) with those who underwent surgery (N = 83). The data were analyzed statistically. Initial evaluation, which included air and bone conduction audiometry, speech discrimination, electronystagmography (ENG), frequency of vertigo attacks per month, and disability, showed both groups to be comparable at the outset. Of the non-operated group 57% had complete control of vertigo at 2 years; 71% had complete control after an average of 8.3 years. After an ELS, 40% of patients had complete control of vertigo after 2 years; 70% had complete control after an average of 8.7 years. After a neurectomy (RVN or CVN), 93% had complete control of vertigo (average followup, 4.4 years). These results indicate statistically that the ELS procedure does not alter the long-term natural course of vertigo control in Menière's disease, whereas both the RVN and CVN significantly improve the patient's chance of being permanently free of vertigo attacks.

Aged↗
PubMed1989

Long-term results of transmeatal cochleovestibular neurectomy: an analysis of 100 cases.

One hundred patients have been treated over a 13-year period with a transmeatal approach to the internal auditory canal for cochleovestibular neurectomy. Ninety-one of these patients have followup of more than 3 months (average, 4.67 years). The most common indication for the procedure was Meniere's disease (71%). Chronic labyrinthitis, usually following stapes, middle ear, or mastoid surgery, was the next most common indication. Patients with the preoperative diagnosis of Meniere's disease had better results in the curing of vertigo (89%) than those having chronic labyrinthitis (68%). Overall, vertigo was cured in 84% of patients and markedly improved in another 15.1%. Tinnitus was relieved or improved in 65% of all patients and in 67% of patients with Meniere's disease. Mild unsteadiness was commonly noticed postoperatively, but only 11% described this as severe. Eighty percent of these latter patients reported unsteadiness preoperatively. Complications were uncommon and temporary: one case of delayed facial paresis that recovered completely, one CSF leak, and one wound infection. There were no cases of permanent facial paralysis or meningitis. The advantages of the transmeatal approach to the IAC for CVN over labyrinthectomy without CVN are assurance of complete labyrinthine denervation, increased likelihood of improved tinnitus, practice at sectioning the posterior ampullary nerve (PAN), and the ability to inspect the internal auditory canal for a small tumor or other pathology. We recommend this procedure for treatment of unilateral vestibular dysfunction in patients with no serviceable hearing.

Adult↗
PubMed1989

Small fenestra stapedotomies with and without KTP laser: a comparison.

The results of 33 small fenestra stapedotomies performed using conventional techniques were compared with the results of 33 stapedotomies performed using the argon or KTP laser. The ossicular chain was reconstructed using a Teflon wire piston of 0.6 mm diameter, and follow-up was at least 1 year. Over-closure of the air-bone gap or closure to within 10 dB was accomplished in 91% of the laser-treated group versus 72% of the conventionally treated group (p less than 0.10). The hearing results were statistically better in the laser group (p less than 0.05). Transient delayed vestibular symptoms, lasting from 1 to 3 weeks, were present in 39% of the laser-treated group and in 12% of the patients treated by conventional techniques (p less than 0.05). The KTP laser stapedotomy, using a micromanipulator mounted on the microscope, is a safe, efficient technique that reduces some of the technical difficulties associated with conventional stapes surgery. The main advantage of the laser is that it enables the surgeon to make an atraumatic, bloodless opening in a fixed or mobile stapes footplate without mechanical manipulation of the stapes. Using a lower wattage to vaporize the footplate and waiting several seconds between laser bursts may decrease the incidence of postoperative vestibular symptoms. The use of the KTP laser in stapes surgery represents a major advance in surgery for otosclerosis.

Fenestration, Labyrinth↗
PubMed1989

Combined retrolab-retrosigmoid vestibular neurectomy. An evolution in approach.

Since introducing the retrolabyrinthine vestibular neurectomy (RVN) in 1978, we have performed 78 procedures with good results. In 1985, we introduced the retrosigmoid-internal auditory canal vestibular neurectomy (RSG-IAC), which allowed a more complete transection of the vestibular nerves in the IAC. Vertigo control has been excellent. However, in 50% of cases postoperative headaches have been a significant problem. In 1987, we combined these two approaches into one procedure, the combined retrolab-retrosigmoid vestibular neurectomy (RSG-RVN). The procedure is similar to a RVN, in that all bone covering the lateral venous sinus (LVS) is removed. It differs from the RVN in that the dura is opened just behind the LVS. The LVS is retracted forward, thereby exposing the cerebellopontine (CP) angle. This allows the surgeon the option to sever the vestibular nerve either in the CP angle or in the IAC, depending on the presence or absence of a cochleovestibular (CV) cleavage plane in the CP angle. The technique, results, and complications will be reported in this article.

Cerebellopontine Angle↗
PubMed1988

The singular canal: a valuable landmark in surgery of the internal auditory canal.

The singular canal transmits the posterior ampullary nerve between the inferior part of the internal auditory canal (IAC) and ampulla of the posterior semicircular canal. The anatomy of the singular canal was studied in temporal bone dissections, in surgical dissections, and in high-resolution computerized tomography scans. Measurements were taken for distances between the origin of the singular canal in the IAC, the porus acousticus, the vestibule, and posterior canal ampulla. The location and importance of the singular canal are demonstrated for retrosigmoid-IAC vestibular neurectomy, retrosigmoid acoustic neuroma surgery, and transcochlear cochleovestibular neurectomy. The main purpose for the use of the retrosigmoid approach to the internal auditory canal during vestibular neurectomy and excision of acoustic neuromas is preservation of hearing. A major concern when the contents of the internal auditory canal are exposed through this approach is fenestration of the labyrinth, which results in sensorineural hearing loss. In the retrosigmoid approach, the singular canal has been found to be a vital landmark in prevention of fenestration during surgery of the internal auditory canal.

Dissection↗
PubMed1988

Routine identification of the facial nerve using electrical stimulation during otological and neurotological surgery.

We routinely identify the facial nerve to avoid facial nerve injury during most otologic surgery. Since 1985, we have used a facial nerve stimulator/monitor as an added safety feature in 383 consecutive otologic and neurotologic cases. In our last 30 middle-ear, 8 retrolabyrinthine vestibular neurectomy, and 14 acoustic neuroma cases we used the monopolar stimulator probe-tip to determine threshold currents needed to produce facial twitch. Stimulation thresholds varied according to the amount of soft tissue or bone overlying the facial nerve. The stimulator was useful for predicting dehiscences in the bony facial canal during middle-ear and mastoid surgery. The exposed facial nerve usually stimulated at a level less than 0.1 mA (mean 0.05 mA), and the horizontal facial nerve covered by bone stimulated at 0.25 mA or greater (mean 0.6 mA). The stimulator was also used to predict the amount of bone overlying the vertical facial nerve at the annulus. An approximate relationship of 1.0 mA of threshold current to 1.0 mm of bony covering was found. After acoustic neuroma surgery, the stimulation threshold of the facial nerve at the brain stem helped predict postoperative facial function. Cases with current thresholds of 0.3 mA or less resulted in normal facial function. During ear surgery, routine identification of the facial nerve with the aid of a facial nerve stimulator will help avoid facial nerve injury.

Ear↗
PubMed1988

Routine intraoperative facial nerve monitoring during otologic surgery.

We have used intraoperative monitoring and stimulation of facial nerve function routinely in 301 consecutive otologic and neurotologic cases. The device has been safe, simple to use, and practical. Facial contraction is detected by a strain-gauge sensor in the corner of the mouth and is signalled audibly to the surgeon. Electrical stimulation of the facial nerve can be delivered through a sterile probe, which produces a constant-current-square-wave impulse. The device has several advantages: it signals unintentional mechanical stimulation of the facial nerve during surgery; it allows mapping of the nerve through soft tissue, tumor, and bone; it predicts dehiscences in the bony covering of the nerve; and it allows confirmation of the electrical integrity of the nerve before and after surgery. In this paper we present a technical description of the device, relevant intraoperative electrical measurements, and illustrative case examples. Although the device does not replace anatomic knowledge and surgical ability, it provides a margin of security during ear surgery. This system for intraoperative facial monitoring is practical, and the authors encourage its routine use.

Adolescent↗
PubMed1988

Multichannel cochlear implantation in a patient with bilateral Mondini deformities.

A 31-year-old man with bilateral Mondini dysplasia was successfully implanted with a Nucleus multichannel 22-electrode cochlear prosthesis. To our knowledge, this is the first report of multichannel cochlear implantation in a patient with Mondini dysplasia. The surgical procedure used to insert the device was uncomplicated. Although objective measurements demonstrated only slight improvement in most categories of the Iowa test battery, he has the ability to discriminate pure-tone frequency differences and environmental sounds. Subjectively, he was a satisfied implant user. The surgical feasibility of multichannel implantation in patients with Mondini dysplasia should open the door for improved speech recognition and tonal discrimination in this subset of patients.

Adult↗
PubMed1987

The treatment of acoustic neuroma and Menière's disease in the same patient.

Although total excision is accepted as the standard of care in the treatment of acoustic neuromas, for the elderly patient this approach is modified. Small tumors which cause only eighth nerve symptoms of hearing loss and tinnitus can be followed radiologically while larger tumors with brain stem compression may be subtotally excised through the translabyrinthine route. Our standard treatment for Menière's disease--that is refractory to medical management--has been vestibular nerve section through a retrolabyrinthine approach. In the event of bilateral Menière's disease or Menière's disease in an only hearing ear, treatment with low-dose intramuscular injections of streptomycin sulfate is preferred. Two elderly patients are discussed, each of whom has an acoustic neuroma in one ear and Menière's disease in the other. These patients' histories, diagnostic evaluations, treatment rationale, and follow-up data are presented to illustrate the decision-making process and the management of complicated and unusual cases.

Aged↗
PubMed1987

Retrosigmoid-internal auditory canal approach vs. retrolabyrinthine approach for vestibular neurectomy.

A new procedure, the retrosigmoid-internal auditory canal (RSG-IAC) vestibular neurectomy, has been developed, presented, and compared with the retrolabyrinthine vestibular neurectomy (RVN). The RSG-IAC involves a 3 cm retrosigmoid craniotomy removal of the posterior wall of the internal auditory canal (IAC) to the singular canal, with transection of the superior vestibular nerve and the posterior ampullary nerve. This effects a complete denervation of the vestibular labyrinth and preserves the patient's hearing. All 11 patients with Meniere's disease were cured of vertigo. Hearing was preserved to within 10 dB of the preoperative pure-tone average (PTA) in 9 of 11 cases. There were no serious complications and no cases of facial paralysis or total hearing loss. The major postoperative problem is persistent headache that necessitates medication. These results compare favorably with--and may be better than those noted after--the RVN procedure. The RSG-IAC vestibular neurectomy is an important improvement in the evolution of vestibular neurectomy for the treatment of vertigo. A prospective study is now in progress to determine which procedure--the RSG-IAC or RVN--best fulfills the goals of vestibular neurectomy.

Ear, Inner↗