Infusible platelet membranes retain partial functionality of the platelet GPIb/IX/V receptor complex.

Infusible platelet membranes (IPMs) prepared from fresh or outdated human platelets have been shown to correct prolonged bleeding times in thrombocytopenic rabbits. In previous trials, IPMs did not seem to be immunogenic and lacked dose-limiting toxicity. The present study was undertaken to explore whether the platelet glycoprotein (GP) Ib/IX/V complex might retain functionality in the IPM preparation. IPMs did not spontaneously bind von Willebrand factor (vWF), but saturable binding could be induced by ristocetin, with a dissociation constant (Kd) of 0.31 +/- 0.03 microgram/mL at 1.0 mg/mL of ristocetin. Of 4 anti-GPIb-alpha monoclonal antibodies tested, AN-51 inhibited vWF binding 67.8% +/- 5.8%, whereas AS-2, AS-7, and SZ-2 were ineffective. Maximal vWF binding induced by botrocetin was only 10% to 15% of that observed with ristocetin. Retention of partial functionality of the GPIb/IX/V receptor allowing vWF binding in a modulated manner seems to represent a critical mechanism by which IPMs may provide hemostatic efficacy.

Endolymphatic system shunting: a long-term profile of the Denver Inner Ear Shunt.

Endolymphatic system surgery for Meniere's disease, particularly endolymphatic shunting, remains controversial. In 1988, we presented our findings on the efficacy of the Denver Inner Ear Shunt in 100 patients. These data were accumulated in the short term. The purpose of this article is to review the long-term results of our endolymphatic shunt procedure, highlighting the population of Denver Inner Ear Shunt recipients. Results were analyzed according to both 1972 and 1985 AAO-HNS criteria. We seek corroboration or refutation of our preliminary conclusion that (a) endolymphatic shunt surgery has little efficacy and that (b) the Denver valve does not appear to offer any advantage in this regard.

Long-term hearing results following stapedotomy.

Stapedotomy, or small fenestra stapes surgery, offers several advantages over total stapedectomy, including less postoperative vertigo and better closure of the air-bone gap at higher frequencies. Although early postoperative results are encouraging for the small fenestra technique, few data are available for longer follow-up periods. In this retrospective study, the hearing results of 35 stapedotomy patients, representing 37 operated ears, were analyzed. Each patient had a follow-up period ranging from 5 to 11 years, with audiograms obtained preoperatively, postoperatively, and at the longterm follow-up intervals. Data obtained included air conduction, bone conduction, and speech discrimination for both ears. The long-term hearing results of the small fenestra technique compared favorably to those reported for total stapedectomy, although a statistical analysis is difficult because of the differing methods used to report the data. Results showed a linear deterioration of air conduction thresholds over time, which corresponded to a decrease of bone conduction thresholds in the operated ear. The rate of deterioration of bone conduction appeared to be the same as that associated with presbycusis alone. After good initial closure of the air-bone gap at all measured frequencies, there was no significant increase in conductive hearing loss with time. In the nonoperated ear, the bone conduction for the speech frequencies deteriorated at a rate significantly higher than that for the operated ear and was probably related to Carhart's effect.

An exercise therapy program for balance disorders.

Patients with chronic balance or disequilibrium disorders can be difficult to evaluate and treat, due to the complex integration of sensory systems which control balance function. There is a trend away from placing these patients on long-term sedative medication. In fact, long-term sedative medications may actually reduce or prevent central compensation. For patients with chronic balance disorders who have already been appropriately treated with medicine and/or surgery, we now strongly recommend an active exercise therapy program, which promotes central compensation and improves general fitness.

Neurotologic presentation of sagittal sinus thromboses associated with oral contraceptive usage.

Thrombosis of the cerebral venous sinuses has long been a recognized complication of late stage pregnancy and the puerperium; more recently, this complication has been associated with the use of oral contraceptives. Two cases are presented in which the presenting symptoms of sagittal sinus thrombosis were neurotologic in nature. One case presented with a sudden onset unilateral facial paralysis; another case presented with pressure/fullness sensation in one ear accompanied by nausea and vomiting. Clinical presentation and evaluation of these cases is presented, with a discussion of symptom etiology. Recommended non-invasive medical management methods are discussed. Cases in which the thrombosis involves the sigmoid, transverse, and sagittal sinuses should be suspect for etiologic sources beyond the ear even when the presenting symptoms are neurotologic in nature. Management of these cases is different from that of an otogenic sigmoid sinus thrombosis. A complete medical history taken from women of child bearing age should include the use of oral contraceptives, which may be suspect for inducing intracranial venous thromboses.

Endoscopic sinus surgery. A 300 case review.

The introduction of ESS (endoscopic sinus surgery) has changed and vastly improved the potential of sinus surgery. It is now possible to visualize obstruction in the natural sinus ostia and remove diseased tissue, thereby promoting restoration of normal function. A series of 300 consecutively performed cases is reviewed; results and complications are reported. Findings include a success rate of 94%, with complications in less than 1%. ESS offers a major advancement in treatment of chronic sinusitis.

Clinical significance of type 5 patterns in platform posturography.

Several abnormal patterns have been identified on the sensory portion of the computerized dynamic posturography test. The vestibular deficit pattern, also known as the "5-6" pattern, is frequently seen in patients with either uncompensated unilateral vestibular lesions, severe bilateral peripheral vestibular loss, or dysfunction involving the vestibular pathways in the brain stem and/or cerebellum. In both sensory conditions 5 and 6, the patient's balance/equilibrium is determined primarily by the vestibular system. A subgroup of the vestibular deficit pattern has been identified, in which only sensory condition 5 is abnormal. This article presents findings in several cases identified with the 5 pattern. Implications for diagnosis and for monitoring the recovery phase after treatment are discussed.

A comparison of facial nerve monitoring systems in cerebellopontine angle surgery.

The use of peripheral nerve monitoring during skull base surgery is becoming a more common procedure. One widely used method (Jako) detects surface muscle contraction, which can be transduced into an audible signal. A 200 microsecond square wave current can be delivered periodically, in order to identify the nerve and verify its integrity. Another monitoring method has been developed, which provides a continuous audible needle electromyographic (EMG) feedback signal from computer averaging of a monopolar low impedance constant voltage stimulus. This study compares facial nerve preservation and postoperative facial nerve function results of three groups of cerebellopontine angle surgical cases: 38 cases performed with no monitoring; 29 cases done with Jako motion detection monitoring; and 41 performed with evoked needle EMG audible feedback monitoring. Postoperative facial nerve function is evaluated using the House-Brackmann grading system. Each of the three study groups are matched for a time at which postoperative evaluation was made. Analysis of results reveals that in addition to the expected increase in facial nerve preservation rates when monitoring is in use, the near real-time feedback provided by audible evoked EMG results in a significant reduction in permanent postoperative facial nerve dysfunction. Using evoked monitoring, a greater proportion of the cases had a final outcome of class I or II results, compared to those cases performed using Jako motion detection monitoring.

Complications of outpatient tonsillectomy and adenoidectomy: a review of 3,340 cases.

Of the 3,340 T&A cases reviewed, 1.4% of the patients experienced major complications, including primary or delayed hemorrhage, anesthetic complications, severe nausea, and dehydration. Less than 1% (0.5%) required hospital admissions. Only 5 patients (0.15%) were identified as patients who would have been in the hospital at the time the complication occurred if all T&A patients had been hospitalized for 48 hours postoperatively. Although this rate of occurrence for complications should not be ignored, it is the opinion of the authors that it is a risk level low enough to be well within acceptable limits for outpatient operations. The trend toward outpatient procedures is one that will undoubtedly grow not only because of the advances in medical technology, which enable the provision of better and safer medical care, but also because of the economic considerations in today's health care world. Currently, the medical profession is in a period of transition to determine which surgical procedures are appropriate for outpatient treatment. As physicians, our concern to provide safe, rational therapy to our patients must preclude all other considerations. Our retrospective case review supports the concept that patients who require T&A, when properly evaluated, can have safe operations on an outpatient basis.

Menière's disease--1983-1989.

A MEDLINE review of Menière's disease for the years 1983 through June, 1989 identified over 300 articles published in the English language. These articles have been reviewed, and those which represent significantly new or different findings from a previously published review article are summarized. Specific studies have been selected to highlight new areas of interest as well as new areas of controversy. Major trends in the period from 1983 through 1989 include a new AAO-HNS criteria for reporting results in Menière's disease, expanding interest in the relationship between immune disorders and Menière's disease, and new long-term studies of endolymphatic shunt procedures, with many reporting that these procedures provide only short-term relief and no long-term preservation of hearing.

Otologic surgery in the outpatient versus the hospital setting.

The results of 11 years experience with 1,577 otologic surgical procedures performed in The Ear & Nose-Throat Clinic, P.A. in Little Rock, Arkansas, a freestanding outpatient surgical setting, are analyzed and compared to 703 hospitalized inpatient cases performed during the same time period. This study includes tympanoplasty, stapedectomy, mastoidectomy, labyrinthectomy and other otologic procedures. Analysis of results in these cases compares hearing results, graft take rates and the occurrence of complications in both the outpatient and inpatient settings. No significant differences are seen between the results or complications in these settings, thus supporting the use of outpatient surgical settings for most standard otologic procedures.

Endolymphatic mastoid shunt surgery using the Denver inner ear shunt.

This study, merging data from two different clinics, was undertaken to evaluate the efficacy of endolymphatic mastoid shunt surgery using the Denver Inner Ear Shunt operation for Meniere's disease. This surgery was performed by the senior authors (C.G.J., J.R.E.D., and M.E.G.) between May 1984 and October 1986, after we attended the Colorado Otologic Research Center (CORC) instructional course. Sixty-six and thirty-four cases, respectively, were performed. Follow-up questionnaires were sent to this total of 100 patients. Fifty-six patients returned completed questionnaires, which formed the basis of this report. A retrospective chart study was also carried out. The results of surgery and questionnaires are reported as statistical data, and, where applicable, the 1985 AAO-HNS criteria for reporting vertigo and hearing results in the treatment of Meniere's disease are used. Preliminary analysis of these data is reported because of its profound effect upon our treatment protocol for patients with Meniere's disease. Results on use of the Denver valve do not appear to be significantly different than the results of other shunt surgery not using the valve.

Herpes zoster oticus: treatment with intravenous acyclovir.

Herpes zoster oticus generally has a poor prognosis, leaving many patients with permanent facial nerve dysfunction. This preliminary report describes results in seven patients treated for zoster; all were given intravenous acyclovir. Patients were infused with 10 mg/kg every 8 hours over a 7-day hospitalization period. Five of the seven patients showed some return of facial function at the time of discharge. At follow-up, 4 patients had achieved a House grade I result, 1 patient a grade II, and 2 patients a grade III. Reasons for the differences in final results are discussed, along with a recommended regimen for treatment.

Automated platelet-sizing parameters on a normal population.

The quantitation of platelets in peripheral blood is a well-recognized tool. However, other platelet parameters that recently have become available on a routine basis with the introduction of automated cell sizers may become increasingly important in evaluating the integrity of the thrombocytic function. These parameters include mean platelet volume (MPV) and platelet-crit (PCT). This study established reliable reference ranges for these platelet parameters while taking into consideration the effects of age and sex in a study population of 447 normal persons. There was an inverse, nonlinear relationship between MPV and platelet count, with no statistical difference (P greater than 0.05) seen between males and females. Platelet-crit showed no variation with respect to age or sex, however, a direct, linear relationship was suggested between PCT and platelet count. These relationships provide a better understanding of these platelet parameters and may contribute to their use as helpful diagnostic aids.