Robert I. Kohut

Endoscopic management of subglottic stenosis with the CO2 surgical laser.

Recent advances in microsurgery of the larynx have heralded a new era in the endoscopic management of subglottic stenosis. The carbon-dioxide laser with bronchoscopic adapters can be successfully employed to reestablish an adequate subglottic lumen. Thirteen cases of subglottic stenosis were managed endoscopically with the carbon dioxide surgical laser. In 77% (10 of 13) of these patients, a satisfactory airway was reestablished within a one-year period. The technique of laser vaporization and the results of treatment are presented. The role of corticosteroid therapy, antibiotic therapy, tracheotomy, dilation, and laryngeal stenting is discussed.

Protein profile of human perilymph: in search of markers for the diagnosis of perilymph fistula and other inner ear disease.

Recent developments in high-resolution two-dimensional polyacrylamide gel electrophoresis, combined with amino acid sequencing and computer-assisted image analysis, have allowed separation of approximately 100 proteins and identification and quantitation of some 30 proteins in human perilymph. The majority of proteins were found to be present in perilymph at levels in basic agreement with the total protein gradient between perilymph and plasma (1:35). However, several striking differences were observed: (1) β2-transferrin, known to be absent from normal plasma but present in cerebrospinal fluid, was detected in perilymph at a concentration roughly equal to that in cerebrospinal fluid; and (2) two high-density lipoprotein-associated apolipoproteins—apo D (formerly PLS:33) and apo J or NA1 and NA2 (formerly PSL:29/30), the latter showing identity with 5P40/40, or cytolysis inhibitor—were found to be present at concentrations 1 to 2 orders of magnitude higher when examined in terms of total protein and to be comparable with or higher than plasma levels when examined in terms of absolute concentrations. The functional significance of the extremely high levels of the two apolipoproteins is not known at this time. An attempt was made to use β2-transferrin, as well as apo D and apo J (NA1/NA2), as markers for the diagnosis of perilymph fistula, one of the most controversial and challenging problems for the otologist today. It was determined that the technique is indeed applicable when relatively pure fistula samples are analyzed. Limitations and potential improvements of the technique are discussed. In addition, the potential usefulness of two-dimensional polyacrylamide gel electrophoresis in other pathologic conditions of the inner ear is discussed briefly.

Perilymphatic Fistula: A Histopathologic Study

Over the last two decades, clinical criteria for perilymphatic fistulae have been defined to the extent that differentiation can be made between such fistulae and other balance-affecting disorders such as Menieres syndrome. On the assumption that the specimens in the temporal bone bank of the University of Chicago Medical School that had been obtained from patients having vertigo, hearing loss, or both, before those clinical criteria were so defined might have been classified incorrectly, we proposed a retrospective histopathologic study, with prediction of two independent variables: 1) a clinical history and physical findings consistent with the diagnosis of perilymphatic fistula and 2) communication between the vestibule and the middle ear adjacent to or via the fissula ante fenestram. Eleven pairs of temporal bones with the histologic diagnosis of idiopathic labyrinthine hydrops were evaluated before the clinical histories relevant to those specimens were reviewed. In one specimen, a communication between the vestibule and the middle ear space was identified. In none of the other specimens was there a similar communication. As this study continued, significance was given to the histologic details of the communication between the middle ear and posterior canal ampulla. The temporal bones without these communications did not have clinical histories consistent with the diagnosis of perilymphatic fistula.

Mucormycosis of the mandible after dental extractions in a patient with acute myelogenous leukemia

Mucormycosis is a fulminant fungal infection that occurs most often in diabetic and immunocompromised patients including those with hematologic malignancies. In this case, a patient with acute myelogenous leukemia developed mucormycosis in a recent mandibular extraction site. The successful management of this patient demonstrated that early diagnosis, aggressive surgical and medical treatment and resolution of the underlying disease could improve the prognosis for survival. A case is made for the role of smoking as an initiator of mucormycosis, and treatment considerations for controlling periodontal and pulpal disease before chemotherapy are discussed.

Minute Perilymph Fistulas: Vertigo and Hennebert's Sign without Hearing Loss

The clinical entity characterized by episodic vertigo and a positive Henneberts sign in patients without hearing loss is described. The history of perilymph fistulas is reviewed. Minute perilymph fistulas of the oval window were documented surgically in five consecutive patients with this syndrome. All experienced relief of their symptoms after surgical correction.

Necrotizing ("malignant") external otitis histopathologic processes.

The histologic findings in a serially sectioned temporal bone, from a patient who succumbed to brain abscess secondary to necrotizing (“malignant”) external otitis, are described. The mechanism of invasion of the ear canal appears to be due to local bone necrosis. This in turn extends to the submucosal vasculature of the pneumatic spaces. The infective process extends submucosally, establishing one or several sites of bone destruction. The lumen of the pneumatic space is not involved. In this process, the periphery of the fibrous inflammatory tissue formation is the site of active bone destruction. In pneumococcal petrositis, the peripheral fibrous elements are protective. The process in malignant external otitis may extend directly to adjacent central nervous system structures inoculating the structure with Pseudomonas. Development of Pseudomonas brain abscesses can be slow, allowing for new bone closure of the site from which the infection spreads as demonstrated in this specimen. Therefore, apparent local control of the disease can be established while a central infective process progresses.

Basophilic Deposits on the Cupula: Preliminary Findings Describing the Problems Involved in Studies Regarding the Incidence of Basophilic Deposits on the Cupula

In this study, the possibility of whether basophilic deposits adhered to the cupulas in the semicircular canals was investigated histologically. Results indicated that basophilic deposits were present in all three cupulas of the semicircular canals. The overall incidence of basophilic deposits in the superior, lateral and posterior semicircular canal cupulas was 26%, 41% and 37%, respectively. The incidence of basophilic deposits bound to the cupulas increased with age. The possible origin of these basophilic deposits on the cupulas and the increased incidence of basophilic deposits with increasing age are discussed.

Perilymph Fistulae: Variability of Symptoms and Results of Surgery

A perilymphatic fistula of a labyrinthine window may initially present with various cochlear or vestibular symptoms. Vestibular perilymph leaks can occur spontaneously with or without hearing loss and are most readily diagnosed by a positive Henneberts sign. Surgical correction is indicated and should initially consist of grafting of the perilymph leak. A significant incidence of recurrence warrants further investigation of grafting materials and techniques.

Airway obstruction in lefort fractures

Airway obstruction associated with fractures of the midfacial skeleton can be life‐threatening if not recognized promptly and treated appropriately. One hundred seventeen patients with LeFort fractures were treated between 1978 and 1984. Of the 117 patients, 21 had a LeFort I fracture, 46 had a LeFort II fracture, 14 had a LeFort III fracture, and 36 had various combinations of the three types of LeFort fractures.

A temporal bone study method to evaluate clinical diagnostic criteria: permeability of patencies of the fissula ante fenestram.

A single-blind study concerning perilymphatic fistulae had shown that the presence of patency of the bony labyrinth capsule in temporal bone specimens could be predicted on the basis of clinical data. In order to demonstrate the potential permeability of fissula ante fenestram patencies, specimens were evaluated using hematoxylin-eosin staining and compared to adjacent sections stained by the Mallory-Trichrome method. This study indicates that this fibrous path in those temporal bones was indeed a patency, and appeared permeable as related to the density of fibrous tissue. Histopathologic studies using human temporal bone specimens are useful, and even imperative, to our understanding of the diseases that affect the organs of hearing or balance. In most instances, these case studies remain the points of reference that are used in explaining the cause of the disorder, the posed pathogenic mechanisms, and the proposed treatment methods. Other than descriptive studies, many reported histologic investigations of diseases of the ear appear to have an unstated general hypothesis: “The histopathologic changes from normal in this specimen are attributable to the patient’s identified medical history and the signs and symptoms of disorders of hearing and/or balance that occurred during life.” Although this hypothesis led to the microscopic study of the membranous structures and the bony capsule of the labyrinth, it also forced conclusions to reflect the presumption that those variables identified during life were accurate, complete, and related to the histopathologic changes.