Impact of CDMA wireless phone power output and puncture rate on hearing aid interference levels.

Interference between digital wireless phones and hearing aids occurs when the radiofrequency bursts from the phone transmission are demodulated by the hearing aid amplifier. The amplified interference signal is heard as a "buzz" or "static" by the hearing aid wearer. Most research and standards development activity has focused on worst-case scenarios with the phone operating at its maximum power. Since this power level is often not typical in urban and suburban settings, it is of value to determine the impact of lower power levels on the overall level of audible interference. Using a frequency analyzer, and several hearings aids and code division multiple access (CDMA) phones, the audio frequency spectrum of interference was recorded for each phone-aid combination and for a range of power levels producing from no interference to maximum interference. As phone power is increased, the interference signal becomes distinguishable from the ambient noise level and a linear response region is observed in which a specified increase in power output results in a proportional increase in the overall input referenced interference level (OIRIL). As power is increased beyond the linear region, the hearing aid enters a saturation region where an additional power increase results in a reduction or no increase in the OIRIL. The numeric differences in interference documented in this study were used in conjunction with the results of a previous study by the authors to determine the impact of reduced power on speech intelligibility and annoyance. The amount of improvement for a given power reduction depends on the radiofrequency immunity of the hearing aid and is substantial for hearing aids with poor immunity. For high-immunity aids, the level of audible interference remains low even at high phone power levels.

Human papillomavirus DNA types in squamous cell carcinomas of the head and neck.

Previous studies have found variable evidence suggestive of a role for human papillomavirus (HPV) in squamous cell carcinoma of the head and neck. In this study 49 cases of primary verrucous or squamous cell carcinoma from patients referred to a regional medical center were examined initially by Southern blot hybridization to detect HPV types 2, 6, 11, 13, 16, 18, and 32. Approximately 60% of carcinomas from certain head and neck sites, particularly the floor of the mouth, tongue, pharynx, piriform sinus, and larynx, were positive for episomal viral DNA of HPV-6, -11, -16, or -18. HPV DNA was found in some multiple tumors from separate sites of the same patient. Integration of viral DNA into the host cell chromosome was likely in a minority of the positive carcinomas, and no novel HPV DNA types were indicated by the hybridization analyses. Subsequently, DNA remaining from 30 of the carcinomas was examined by a more sensitive polymerase chain reaction amplification assay for DNA of HPV-6, -11, -16, and -18. Twenty-seven of the samples were positive for one or more HPV DNA types, with all positive carcinoma samples containing oncogenic HPV-16 or -18 DNAs. Almost all the patients examined were of the middle to older age group with a history of tobacco use. Although HPV infection of oral mucosa may be a frequent occurrence, a possible role for HPVs in the multifactorial etiology of head and neck carcinogenesis merits further epidemiologic investigation.

Orbital complications of sickle cell disease.

Swelling and pain of the peri-orbital tissues in patients with sickle cell disease has been described. This has most often been ascribed to orbital apex syndrome, but there are recent reports in the literature of frontal bone infarctions compounding this syndrome. We will present a case report of a child with sickle cell disease with bilateral orbital abscesses and frontal bone infarctions. The literature pertaining to the diagnosis and treatment of the orbital complications of sickle cell disease is reviewed. We stress that intravenous antibiotics are not adequate therapy for orbital abscesses and that these must be drained surgically.

Exacerbation of sickle cell disease by obstructive sleep apnea.

It is difficult to recognize and treat the factors that exacerbate the vascular crises of sickle cell disease. We describe a 12-year-old black girl with sickle cell anemia who, since the age of 9 years, has been repeatedly hospitalized for pain associated with vaso-occlusive disease. A diagnosis of obstructive sleep apnea was suggested by the history and physical examination and was confirmed by polysomnography. Following preoperative transfusion, the patient underwent elective tonsillectomy and adenoidectomy. She has been free of vaso-occlusive pain and crises for over two years and has not been hospitalized since her surgery. Post-operative polysomnography has shown no evidence of obstructive sleep apnea. It is our hypothesis that repeated oxygen desaturation during periods of obstructive sleep apnea was the cause of this patient's frequent vaso-occlusive crises. She not only obtained complete relief of her symptoms, but objective sleep study measurements were normal following surgery. Obstructive sleep apnea is a recent diagnosis, and its pathologic effects are only beginning to be known. Physicians taking care of patients with hemoglobinopathies need to be aware of possible contributing factors to their patients' disease, and an aggressive approach to their diagnosis and possible relief should be sought.

Readily available full-thickness mucous membrane graft.

A uniformly thin, nonfatty, full-thickness mucous membrane graft measuring a minimum of 4 X 5 cm is described for an unusual clinical problem, total symblepharon. The donor graft's ready availability from a normal maxillary sinus, its ideal grafting characteristics, and minimal donor site morbidity make it an ideal choice in many other clinical situations. This thin yet full-thickness graft minimizes graft contracture and maximizes rapidity of graft "take," making it an excellent choice for tracheal or laryngeal relining procedures, release of oral cavity scar contractures, or pharyngeal reconstructions.

The implications of "controlled" studies of tonsillectomy and adenoidectomy.

The controversy over the efficacy of adenotonsillectomy is resolved in only very select clinical situations. An attempt is made to summarize and objectively criticize available data in this ongoing debate.

Comparisons of tracheostomy incisions in a pediatric model.

Tracheostomy in children causes approximately twice the mortality and morbidity as in the adult. The occurrence of complications correlates closely with the severity of the preoperative tracheal disease, the length of time the tracheostomy is needed, and the age of the patient. Morbidity documented in the postoperative period includes tracheal stenosis and collapsible anterior tracheal wall. The increased incidence of these problems in the pediatric patient may be related to the less rigid nature of the younger cartilage or to partial arrest of the normal tracheal growth rate, and may be aggravated by the style of tracheal incision used. Our study utilized weanling male ferrets in an effort to evaluate the possibly different response of growing, less resilient cartilage to different types of tracheal incision. Animals were randomized into three groups based on the type of incision used: inferiorly based trapdoor, vertical slit, or horizontal H. Endoscopic, radiographic, and airflow studies, as well as cross-sectional areas, were compared on all animals surviving tracheal cannulation for eight days and subsequent decannulation for seven days. Recommendations for pediatric tracheal incision are made on the basis of these studies.

Tracheal reconstruction with pedicled thyroid cartilage.

Limited areas of tracheal stenosis have been repaired with a variety of techniques. More extensive upper tracheal defects present a greater challenge with less predictable success. The following is the description of yet another technique for reconstruction of extensive upper tracheal defects. We report on the use of a muscle-pedicled thyroid alar graft which carries its own blood supply and perichondrial covering, supplies a large, conveniently shaped graft, requires one operative site and one operative sitting, and has proven advantageous even in the comprised patient.

A new complication of prosthetic ossicular reconstruction.

The use of synthetic partial ossicular replacement prostheses (PORPs) and total ossicular replacement prostheses (TORPs) in ossicular reconstruction surgery has gained growing acceptance but is not without complication. Dysgeusia, resulting from tension or stretching of the chorda tympani, was noted in two patients who had undergone such reconstruction. The symptoms resolved following resolution of the tension on the chorda tympani.

The nose, minor salivary glands, and sarcoidosis.

Fifty-nine patients referred to the ear, nose, and throat clinic for random minor salivary gland (MSG) biopsy were studied. After a careful head and neck examination, a random MSG biopsy and a random inferior turbinate or specific nasal lesion biopsy was done. Of 30 patients with bilateral hilar lymphadenopathy (BHL), 12 of 26 who were thought to have sarcoidosis had abnormal findings on MSG biopsy. Of 29 patients without BHL, none of the six who were later believed to have sarcoidosis had abnormal findings on MSG biopsy. The other 23 patients without BHL and who later were believed findings on MSG biopsy. A careful history, physical examination, and chest roentgenogram should precede referral for random MSG biopsy. Patients without BHL and without other evidence for systemic sarcoidosis do not benefit from random MSG biopsies. This is especially true because of the relative nonspecificity of the finding of a noncaseating granuloma.

Effects of laser, scalpel, and electrosurgical excision on wound contracture and graft "take".

Current literature recommends the use of a carbon dioxide laser for excision of lesions where minimal damage and wound contracture are desirable. The extent of tissue damage is evaluated as a correlate of percentage of split-thickness skin graft "take" following excision of full-thickness skin with scalpel, electrocutting current, or carbon dioxide laser. The poorest overall percentage "take" is apparent following laser excision, while the highest overall percentage "take" occurs following scalpel excision. Wound contracture, an inherent part of wound healing, is reportedly minimal or clinically inapparent with laser excision. On the contrary, this experimental evaluation suggests that wound contracture following laser excision is at least as great if not greater than that following other methods of excision when a split-thickness skin graft is applied to the wound bed.

Frontal sinus trephination: a new technique for office procedure.

A new office technique for frontal sinus trephination is described. The procedure is simple, expedient, and inexpensive. Our experience with 16 patients suggests that this procedure is reasonably safe and, in addition, avoids the often-seen complications of supratrochlear nerve injury and persistent noticeable scar.

Otoscopy and photography: a new method.

A new hand-held otoscope photographic system, convenient and suitable for clinical application, is introduced. This instrument allows clear otoscopic examination in stenotic or tortuous ear canals, and photographs the subject in one procedure. The instrument consists of a rod-lens optical system, a fiberoptic light source, a camera, and exchangeable speculum and a strobe light. Color photographs of tympanic membranes and middle ear pathology are presented.

Evaluation of otic drops on infection and healing of traumatic tympanic membrane perforations.

Guinea pigs were used to compare the efficacy of three commercially available otic preparations in treating traumatic tympanic membrane perforations. The results suggest that a clear, viscous solution of low pH will significantly reduce the incidence of infection and will not retard subsequent membrane healing.

Renal toxicity. Tobramycin and gentamicin.

The new aminoglycoside, tobramycin sulfate, has been shown to be effective against the same microorganisms for which gentamicin is currently employed. This study compares the effects of these two antibiotics on renal function and ultrastructure in guinea pigs. Significant differences in the blood urea nitrogen of treated and nontreated groups, as well as between the gentamicin- and tobramycin-treated groups were observed. Gentamicin produced greater, more rapid elevations of the blood urea nitrogen, although all elevations were reversible. The ultrastructural pathology produced by tobramycin was similar to that previously described for gentamicin.

Pathogenesis of pyelonephritis. Escherichia coli-induced renal ultrastructural changes.

Escherichia coli-induced renal ultrastructural changes were observed 4 hr after the intravenous injection of 2 times 10-minus 6 bacteria. The initial changes consisted of mitochondrial swelling followed by intracellular vacuolation, nuclear membrane dilation, and increased lysosomal phagocytic activity. Alterations in the appearance of proximal tubular lysosomes included a loss of osmiophilic staining properties. Many of the involved cells showed necrosis and can presumably act as a nidus for bacterial proliferation.