Faculty Bibliography

The head-and-neck manifestations of HIV infection in children are very different from those in the adult population. Recurrent bacterial and viral infections are common manifestations, and persistent sinusitis or otitis media should make the otolaryngologist suspicious of HIV infection if the child has been exposed to the virus. Other common problems include mucocutaneous and esophageal candidiasis, recurrent herpes I and II and zoster infections, parotid swelling, and cervical lymphadeopathy.

Reconstruction of columellar defects continues to be a surgical challenge. We present the results of two child-abuse patients who were successfully treated with a technique in which medially based bilateral horizontal nasolabial flaps were used to reconstruct total columellar loss. Our technique provides adequate tissue with minimal cosmetic deformity. It also obviates the need for multiple staged procedures. We recommend the use of this method for repair of either partial or total columellar defects secondary to trauma or infection.

Munchausen syndrome is uncommon in otolaryngology. Self-induced otitis externa has rarely been reported, and nothing is known concerning the true incidence of feigned vertigo. We present a patient who has been hospitalized several times and who has undergone ear surgery and treatment at different institutions along the eastern seaboard. She has suffered complications of therapy, including a profound sensorineural hearing loss, and was referred to us for surgical treatment of bizarre intractable otitis externa. The infection failed to respond to medical treatment and was ultimately found to be self-inflicted. Despite psychotherapy, the patient continues to seek further treatment at still other hospitals. This entity must be considered whenever a thorough evaluation fails to yield a reasonable organic diagnosis.

We describe a case of fibrous histiocytoma of the trachea diagnosed in a 17-year-old female who presented with symptoms of 'asthma'. Management included rigid bronchoscopy with biopsy and debulking of this obstructing tumor, later excised with partial tracheal resection. Although tracheal tumors are quite rare in children, the majority (6/9) of reported cases of fibrous histiocytoma of the trachea have been described in the pediatric age group. The possibility of a tracheal neoplasm as a cause of wheezing, stridor or hemoptysis in children should be recognized. Control of the airway without tracheotomy may facilitate surgical cure via tracheal resection in such cases.

Although neurosurgeons have traditionally preferred intracranial repair for the management of cerebrospinal fluid (CSF) fistulas, this approach is associated with the complications of a craniotomy, anosmia, and a high incidence of recurrent fistulas. Extracranial repair, on the other hand, produces no central nervous system morbidity, preserves olfaction, and is associated with a low incidence of recurrence. Although there have been several reports of extracranial repair of CSF fistulas by otorhinolaryngologists, this approach has received scant mention in the neurosurgical literature. We report here our experience with 37 patients with CSF rhinorrhea or otorrhea who underwent extracranial repair. The etiology of the fistula was postoperative in 22, traumatic in 6, and spontaneous in 9. The fistulas were repaired using one of four techniques: external ethmoid-sphenoid in 18 patients, transmastoid in 9, transseptosphenoid in 7, and osteoplastic frontal sinusotomy in 3. In 32 of the 37 patients (86%) the fistulas were successfully repaired with the initial procedure. Of the 5 patients requiring a second operation, the fistula was successfully closed in 4 for an overall success rate of 97%. Complications were few and consisted of a transient facial paresis in a patient undergoing transmastoid repair and one death from meningitis. The authors conclude that because of low morbidity and mortality and a high success rate in closing fistulas, extracranial repair is the preferred technique for the operative management of CSF rhinorrhea and otorrhea.

The purpose of the present study was to analyze and compare the amplitude spectra of ABRs recorded from 40 elderly and 40 young subjects in order to determine if there are any age related differences. A spectral analysis was performed on each subject's ABR. It was found that the ABRs recorded from older subjects have a significantly greater amount of low frequency spectral energy than ABRs recorded from young subjects. This difference was attributed to the greater amount of low frequency background noise found in the ABRs of older subjects. Modification of standard recording procedures should be considered when ABRs are recorded from older subjects.

A recent increase of interest in spectral analysis has been prompted by the suggestion that spectral components of the ABR may contribute to differential diagnosis. Knowledge of the effects of stimulus parameters on the spectral content of the ABR is essential. The present study examined the effect of intensity, rate, and polarity on the spectral content of ABRs of 15 normal-hearing subjects. The effects of intensity were significant at all spectral frequencies examined while the effects of rate and polarity were frequency specific. These results indicate that the effects of stimulus parameters must be considered in examining the ABR spectral analysis.

Osteogenesis imperfecta type I is a mild, dominantly inherited, connective tissue disorder characterized by bone fragility. Mutations in type I collagen account for all known cases. In Mov-13 mice, integration of a murine retrovirus within the first intron of the alpha 1(I) collagen gene results in a null allele blocked at the level of transcription. This study demonstrates that mutant mice heterozygous for the null allele are a model of osteogenesis imperfecta type I. A defect in type I collagen production is associated with dominant-acting morphological and functional defects in mineralized and nonmineralized connective tissue and with progressive hearing loss. The model provides an opportunity to investigate the effect of a reduced amount of type I collagen on the structure and integrity of extracellular matrix. It also may represent a system in which therapeutic strategies to strengthen connective tissue can be developed.

This study assessed the contribution of the apical hair cells to hearing. Guinea pigs, chinchillas and monkeys were behaviorally trained using positive reinforcement to respond to pure-tone stimuli. When a stable audiogram had been determined, each subject received one of three experimental treatments: ototoxic drug administration, low-frequency noise exposure, or the application of a cryoprobe to the bony wall of the cochlear apex. After post-treatment audiograms stabilized, subjects were euthanized and the percentage of hair cells remaining was assessed by light microscopy. Results indicate that a redundancy of encoding mechanisms exist in the mammalian cochlea for low-frequency stimuli. They also suggest that a very small percentage of apical hair cells are sufficient for some low-frequency hearing. Finally, data from this and other studies suggest that the low-frequency threshold shift caused by the loss of a certain percentage of apical hair cells is less pronounced than the high-frequency threshold shift caused by the loss of a comparable percentage of basal hair cells. These data agree with anatomical and electrophysiological evidence that functional as well as anatomical differences may exist between the apex and base of the cochlea.