Paper patch repair of blast rupture of the tympanic membrane.

An hotel explosion provided a need to treat five blast ruptured tympanic membranes in four firemen. Treatment consisted of early debridement and eversion of tympanic membrane flaps, Gelfoam to support these flaps and the placement of a paper patch for immediate closure of the drumhead defect and to provide a plane for epithelial growth. Pre and postsurgical audiometry demonstrate the immediate rehabilitation of conductive hearing in these patients. In all cases, immediate improvement in symptoms of aural fullness occurred. Tympanic membrane defects healed with minimal scarring in each case. Early debridement and paper patch repair are recommended for blast-ruptured tympanic membranes.

Transoral approach to the upper cervical spine.

The transoral approach to pathology of the upper cervical spine is logical, but it is seldom used due to concerns about exposure and infection. The authors report on 16 consecutive patients requiring exposure from clivus through C3 for pathology, including spinal cord compression by rheumatoid pannus, craniovertebral anomalies, and tumor. Exposure was obtained using a Dingman mouth gag and soft palate retraction with silicone rubber sheeting. A horizontal "H" incision was made in the posterior pharyngeal wall creating three layers, closed separately, with attention to a watertight closure of the final mucosal layer. In no case was it necessary to divide the mandible, tongue, soft palate, or uvula. There were no deaths, wound breakdowns, infections, or persistent cerebrospinal fluid leakage. Patients with neurological indications improved postoperatively, and all tumors were grossly resected. Combined otolaryngology/neurosurgical exposure and treatment of pathology involving the upper cervical spine via the transoral approach is safe and effective. Functional results have been excellent, and no major complications were encountered.

A comparison of speech using artificial larynx and tracheoesophageal puncture with valve in the same speaker.

Postlaryngectomy speech rehabilitation more frequently includes surgical-prosthetic methods since the introduction of a low morbidity tracheoesophageal puncture technique and a one-way airflow valve. This study compares speech using an artificial larynx and, in one case, esophageal speech with speech using a tracheoesophageal puncture and valve in the same speaker. Using nonprofessional listeners, speech was rated for intelligibility and preference. Voice spectrograms were employed for measurement of rate, fundamental frequency, and intensity. While no statistically significant differences were found in mean fundamental frequency or intensity, the rate of post-tracheoesophageal speech was considerably faster. In addition, when individual speakers are compared with themselves, post-tracheoesophageal speech is significantly more intelligible and preferred by naive listeners. We conclude that using the tracheoesophageal puncture with valve should be strongly considered in total laryngectomy patients whose present mode of communication is unsatisfactory.

Margins of safety with transantral orbital decompression.

This study involves evaluation of the surgical limits of transantral orbital apex decompression (as described by Ogura) by performing the operation on 17 cadaveric half-heads. Measurements were then made of the proximity of bone removal to several vital structures including the optic nerve, carotid artery siphon, cavernous sinus, and frontal lobe dura. Entrance into the sphenoid sinus was found to be routine. Adequate decompression requires maximum removal of bone at the orbital apex and incision of the periorbita without damage to the adjacent vital structures. This requires; 1. knowledge of ethmoid and sphenoid sinus anatomy and recognition of anatomic variations, 2. removal of bone under direct visualization, and 3. incisions of the periorbita be made most posteriorly first to prevent prolapse of orbital fat anteriorly which obscures vision of the critical orbital apex periorbita.

Facial bone augmentation using Bioglass in dogs.

In the quest for a material other than autograft and homograft bone for use in facial augmentation and replacement, materials scientists have developed numerous inert materials, some of which have a porous structure allowing scar tissue ingrowth to aid in stabilization of the implant. This study investigates a bioactive, nonporous, transparent glass (Bioglass) in a dog model for use in facial bone augmentation. In 18 dogs studied in three groups at 1, 3, and 6 months, Bioglass implants developed a bond to bone or soft tissue in 54 of 72 instances (75% of the time). Poor bonding of mobile chin implants and the loss of three implants due to infection accounted for all but three of the 18 failures. Histologic evaluation revealed no untoward tissue response. Because of the tissue bonding ability and amenability to contouring with a diamond bur at the time of surgery, Bioglass is promising as a graft material for facial bone augmentation.

Comparison of biomaterials for facial bone augmentation.

We compared the gross behavior of and microscopic response to implant materials currently in clinical use for facial bone augmentation at different sites in dogs. Materials evaluated include porous polytetrafluoroethylene carbon (Proplast), large-pore high-density polyethylene (Medpor), solid medical-grade silicone rubber (Silastic), polyamide mesh (Supramid), and autogenous rib bone. The subjects were 12 mixed-breed dogs and the materials were implanted directly on bone with periosteum removed at one of three sites in the dog's face (malar eminence, nasal dorsum, and chin). Animals were killed 3 months after surgery and stability of the implants was graded by manual manipulation. Blocks of tissue, including the study materials and underlying bone, were examined microscopically after sectioning. Stability results are tabulated and histologic appearance is described by site for each material evaluated. These data demonstrate marked variability of stability and cellular response depending on the site of implantation. From these data one may conclude that the site of implantation and implant movement are essential factors in determining the nature of the tissue response and fate of an implant. Solid and porous alloplastic materials show an acceptable tissue response, but neither demonstrates the ability to consistently provide an implant that is stable on underlying bone.

Effects of hyperbaric oxygen and irradiation on experimental skin flaps in rats.

This study investigated the effects of hyperbaric oxygen (HBO) and irradiation (RT) on experimental skin flaps in rats under varying conditions. Animals were assigned at random to 1 of 15 groups that represented all possible ordering effects of HBO, RT, and flap, as well as controls that included flap-only, RT-only, and HBO-only groups. Cranially based skin flaps measuring 3 x 9 cm were elevated on the dorsum. The surviving length was evaluated with fluorescein dye 7 days after the operation. Rats receiving HBO were subjected to four consecutive 2-hour treatments of 100% oxygen at 2.5 atmospheres with half-hour intervals of room air. Depending on the treatment condition, HBO was given either 48 hours or 24 hours before flap elevation, or within 4 hours or 48 hours after flap elevation. Rats receiving RT (60Co) were given a single dose of 1000 rads to the dorsum. Results showed that all groups receiving HBO within 4 hours after flap elevation had significantly greater flap survival length (P less than .05), with as much as a 22% greater length of surviving flap. HBO given 48 hours before flap elevation also significantly improved flap survival over controls (P less than .05). RT appeared to have no immediate significant effect on flap survival. However, rats receiving RT, regardless of other factors, gained significantly less weight than did controls (P less than .001). Findings clearly indicate that, to be effective, HBO needs to be given as soon after surgery as possible.

Comparison of ossicular replacement materials in a mouse ear model.

Four biomaterials, UF45S5 Bioglass, Silastic, Plasti-Pore, and Proplast, were used to replace the incus in a mouse ear model. Bioglass, a bioactive glass ceramic, compared favorably with the other test materials in maintaining surgical positioning between malleus and stapes and remaining stable to a blast of nitrogen gas and to pick manipulation. In a short-term animal study, Bioglass showed histocompatibility comparable to that of these other implant materials now used in ossicular replacement surgery in humans.

Bioglass middle ear prosthesis: preliminary report.

The current status of materials for use in middle ear reconstruction is discussed with particular emphasis given to alloplastic implants including bioinert and bioactive materials. Bioglass is a bioactive transparent glass which forms a bond with living tissues. Its development and characteristics are discussed, and the early results of a clinical trial using a Bioglass middle ear prosthesis are presented. The satisfactory tissue response and hearing results found in this preliminary group of patients encourage further clinical evaluation of the Bioglass middle ear prosthesis for use in ossicular reconstruction.

Necrotizing sialometaplasia of the nasopharynx.

Necrotizing sialometaplasia is an uncommon salivary gland disease originally described by Abrams et al in 1973. The disease may occur wherever salivary gland tissue is found. Theories on the etiology of this disorder have been advanced, but never definitely determined. Treatment consists of adequate biopsy and observation until healing occurs at six to eight weeks. While the disease is considered benign, its similarity to more aggressive neoplasms can be both disturbing and misleading to the patient and the clinician. Such a case of necrotizing sialometaplasia of the nasopharynx is presented to demonstrate the clinical and histological similarity of this disease to carcinoma. In this case, the patient first presented with a neck mass which could easily have been mistaken for a regional metastasis. The current literature is reviewed.

Treatment of maxillary cysts.

Differing classification systems for cysts of the maxilla have resulted in confusion in the literature regarding these cysts. We feel that proper evaluation and treatment is essentially the same regardless of the classificatory system employed. The hallmark of proper treatment of these cysts is meticulous removal of all cyst lining to prevent recurrence. Three case reports are presented and discussed.

Lack of effect of carbonic anhydrase inhibition on direct measurements of endolymph bicarbonate.

In the past, sodium, potassium, and chloride have been measured in endolymph directly, but bicarbonate has been measured only indirectly. We sampled endolymph directly while monitoring endocochlear potentials in normal and methazolamide-treated guinea pigs. Bicarbonate was determined in samples by use of a method that depends on reduction of NADH to NAD linked to malate formation from oxaloacetate. In 11 normal animals, the bicarbonate in endolymph was 20.2 mM +/- 4,4 mM (mean +/- standard deviation); in six of these, plasma bicarbonate was 23.1 mM +/- 3.5 mM. Nine animals treated with methazolamide (carbonic anhydrase inhibitor) had an endolymph bicarbonate of 19.5 mM +/- 3.9 mM; plasma bicarbonate in five of these was 25 mM +/- 3.2 mM. Carbonic anhydrase inhibition did not significantly affect endolymphatic bicarbonate levels.

Arytenoid dislocation.

The reported incidence of arytenoid cartilage dislocation is low. This may be due to the wide range and orientation of motion allowed by the cricoarytenoid articulation and the laxity of its joint capsule. In two previously reported instances of arytenoid dislocation, the authors have suggested that endotracheal intubation is generally not sufficient to cause dislocation of an arytenoid cartilage, but that, in their cases, a predisposing factor had set the occasion for dislocation. In this communication, three cases of arytenoid cartilage dislocation, which each followed a single instance of endotracheal intubation are presented. In all three cases, painful swallowing was the main presenting symptom. Clinical features that differentiate arytenoid cartilage dislocation from vocal cord paresis are summarized. Early reduction of the dislocation, while the patient is under local anesthesia, is recommended, and the techniques are described in detail.

Biomaterials for facial bone augmentation: comparative studies.

Presently no material is available which is entirely satisfactory for facial bone augmentation. These studies examine several of those already in clinical use, made from various polymers in solid, porous, and woven forms. Homograft bone has also been studied, as an implant material. All materials were used in situations for which they are currently recommended clinically. Bioglass (Bioglass is a trademark of the University of Florida) implants, which are suggested for clinical use, have been studied in the same model and results show that their surface activity provides a more satisfactory immobilization, both in the short and long term, than does the tissue ingrowth on which most of the other materials depend. Results show that in this model as well as in clinical practice, porous and woven materials provoke in tissues a continuing cellular response which will always compromise long-term clinical success. Autograft bone has associated morbidity and is unpredictable with respect to its incorporation into host tissue and persistence at the site. Bioglass, however, was immobilized successfully at both hard and soft tissue interfaces without the need for porosity, could be satisfactorily shaped in the operating room, and, in addition, had the bonelike hardness which is not provided by any other available material.

The effects of varying the number of cochlear implant electrodes on speech perception.

The purpose of this investigation was to evaluate the speech perception of a patient fitted with a multichannel processor under different electrode conditions. The subject was evaluated with the speech processor programmed with electrode arrays varying in number from one to nineteen. The results suggested that with an increased number of programmed electrodes, the subject's speech perception improved. Comparisons were also made among three speech processing strategies. The processor was programmed with: (1) one electrode pair that provided fundamental frequency information; (2) nineteen electrode paris that provided fundamental frequency plus second formant information (F0/F2); and (3) nineteen electrode paris that provided fundamental frequency plus first and second formant information (F0/F1F2). The subject did better with the F0/F2 strategy compared to the F0 strategy and best with the F0/F1F2 strategy.

A double blind investigation of piracetam (Nootropil) vs placebo in geriatric memory.

Fifty-six hospitalized geriatric patients between the ages of 65 and 80 were given piracetam (Nootropil) 2400 mg/day or placebo on a double blind basis over a two month period. Every patient submitted to a battery of psychological tests before and after the two month trial. These tests included the Similarities, Vocabulary, Digit Symbol, and Block Design subtests of the Wechsler Adult Intelligence Scale; Graham Kendall Memory for Design; Benton Visual Retention; Hooper Visual Organization; Raven Colored Progressive Matrices A, AB, and B; Wechsler Memory Scale A and B; Porteus Maze and Finger Tapping. Patients who were unable to complete this battery were not included in this investigation. In addition, at pretreatment, 4 and 8 weeks, the patient completed a Profiles of Mood States, a Clinical Global Evaluation was done by the investigator, and laboratory determinations were performed. Fifty Patients completed the investigation (25 piracetam, 25 placebo). There were no significant statistical differences between the two groups of patients on all measures utilized except for the Clinical Global Evaluation, where 52% of the patients on piracetam showed minimal improvement versus 25% of the placebo group (P less than 0.05).

Effects of cochlear ablation on local cerebral glucose utilization in fetal sheep.

Local cerebral glucose utilization was measured by the [14C]-deoxyglucose method in five near-term fetal sheep in whom bilateral ablation of the cochleae had been accomplished aseptically 5 to 8 days earlier. The tympanic membrane and ossicles were removed and all turns of each cochlea were unroofed with destruction carried to the modiolus. Mean local cerebral glucose utilization of 33 of 34 gray matter structures and four of four white matter structures in operated animals were significantly lower (p less than 0.05) than that in unoperated control fetuses. The depression in local cerebral glucose utilization was greatest (p less than 0.002) in brain stem auditory nuclei, in which the mean rate of glucose utilization was approximately 25% of the levels in unoperated fetuses. The pattern of glucose utilization in these structures was clearly altered, with a reversal of the normal distribution in density of the inferior colliculus. Tonotopic bands of high local cerebral glucose utilization frequently seen in autoradiographs of inferior colliculus in unoperated fetuses were not observed in operated fetuses. These results show that the glucose utilization of the brain, and by implication the normal growth and maturation of the brain, depends on an intact auditory system during prenatal life.