PubMed Health⌕ Search

Biomedical subjects

R I Kohut

Publications and source records attributed to R I Kohut.

At least 19 recordsLinked to original sources
PubMed1992

Perilymph fistulas. Clinical criteria.

A perilymph fistula may be defined as an abnormal opening between the inner ear and the external surface of the labyrinth capsule, which allows the escape of perilymph and causes specific disorders of hearing, balance, or both. Its diagnosis remains somewhat controversial. This communication presents a defined set of clinical diagnostic criteria, the historic context by which those criteria have been developed, the histopathologic and clinical studies by which they have been challenged or substantiated, and the deficiencies that remain in our understanding of the pathogenic mechanisms that allow for abnormal cochlear or vestibular function.

Fistula↗
PubMed1991

The histologic characteristics of the core of the fissula ante fenestram.

In earlier studies of perilymphatic fistulae, we described their histologic criteria and the clinical criteria for the identification and prediction of patencies of the labyrinth capsule related to disorders of hearing and balance. These patencies were either of the fissula ante fenestram or of the round window niche-posterior canal ampulla fissure. The permeability of the fibrous core of a patent fissula ante fenestram has been questioned, authors of some earlier articles arguing that the tissue is loose, others that it is dense. This study demonstrates loose fibrous and cellular structure in the fissula's tract, dense collagen at the circumference. The loose arrangement of tissue suggests that fluid can pass through this patency, and it appears similar to that of the spiral ligament which has been shown to contain perilymph by way of intercellular communications with the perilymphatic space.

Ear, Middle↗
PubMed1990

Clinical diagnosis of anterior inferior cerebellar artery thrombosis. Autopsy and temporal bone histopathologic study.

A patient having the diagnosis of an anterior inferior cerebellar artery insufficiency died 36 hours after the onset of the symptoms that allowed this diagnosis. The special features of this study include a known symmetric 40-dB hearing loss 1 year prior to the onset of the symptoms, the noted decrease in hearing and severe vertigo heralding the vascular accident, the ensuring neurologic deficits, and the short duration of the patient's life after the onset of her symptoms. The patient's clinical course and the histopathologic findings of the brain stem involved the vestibular nuclei, facial nerve, nuclei of nerve V, restiform body and middle cerebellar peduncle and labyrinth including loss of sensory epithelium of the cochlea and vestibular system and the ganglion cells of Scarpa's ganglion. These findings are correlated with previous animal studies and those of Reye's syndrome. To the authors' knowledge this is the first report of a temporal bone histopathologic study from a patient having had the diagnosis of a labyrinthine arterial vascular accident.

Aged↗
PubMed1976

Metastatic adenocarcinoma of the temporal bone.

Metastatic carcinoma involving the temporal bone is an unusual occurrence. A review of the world literature reveals a total of 102 reported cases. Secondary cancers of the temporal bone arise most frequently from mammary, renal, and bronchogenic carcinomas, all of which show a tendency to metastasize to bone. The pathogenesis of spread to the temporal bone is most commonly by the hematogenous route, but extension from intracranial involvement has also been noted. The symptoms of facial nerve paralysis, otalgia, and aural discharge are consistently associated with patients found to have aural cancers. These symptoms are, however, most frequently indicative of mastoid infection; it is therefore, imperative to consider the possibility of a malignant neoplasm in patients with these symptoms.

Adenocarcinoma↗
PubMed1976

One-stage dermal pedicle flap reconstruction of the oropharynx (an experimental and clinical study).

A single stage dermal pedicle graft method for reconstruction of oropharyngeal defects is presented. Its successful clinical use is described. The advantages of the method include large surface-to-surface anastomosis which appears to minimize breakdown secondary to hypovascularity of an irradiated recipient bed. Other advantages include its single stage feature, persistent blood supply, avoidance of external tubed pedicles and intermediate salivary fistulas. A histologic study in pigs preceded its clinical use in humans. Findings of both aspects of the study are discussed.

Animals↗
PubMed1975

Aural abnormalities in partial DiGeorge syndrome.

DiGeorge syndrome patients frequently have multiple anomalies of the craniofacial, cardiovascular, and visceral structures in addition to thymic and parathyroid hypoplasia. Gross and microscopic aural abnormalities occurring in a patient with partial DiGeorge syndrome are presented and compared with findings from the only other known temporal bone report.

Abnormalities, Multiple↗
PubMed1975

Macular amyloidosis with localized amyloidosis of upper air passages.

A patient with primary amyloidosis of the upper air passages was found to have cutaneous macular amyloidosis. A review of the literature indicates that this may represent the first report of these two uncommon forms of amyloidosis occurring in the same individual. Biopsy material from the nasopharynx, tonsillar areas, larynx, trachea, and skin showed amyloid in the tissue sections. Special stains were used and polariscopic studies were performed, and the hyalin material met the established criteria for amyloid. Studies of tissues from other parts of the body of this patient failed to demonstrate amyloid.

Amyloidosis↗
PubMedDate not supplied

Embolization techniques in vascular tumors of the head and neck.

Surgical excisions of vascular tumors of the head and neck are frequently associated with difficulties because of the potential of operative blood loss. The technique of selective percutaneous embolization before surgery has emerged as a valuable adjunct-and even alternative-to surgery in the management of such lesions. By reducing the blood flow to a vascular tumor or arteriovenous malformation, embolization techniques can be greatly facilitate surgical excision. The participation of a qualified invasive radiologist is essential. If cases are carefully selected and procedural details strictly adhered to this technique can be quite valuable to surgeons treating vascular lesions of the head and neck.

Adolescent↗
PubMedDate not supplied

Minute perilymph fistulas: vertigo and Hennebert's sign without hearing loss.

The clinical entity characterized by episodic vertigo and a positive Hennebert's 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.

Adult↗
PubMedDate not supplied

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.

Aged↗
PubMedDate not supplied

Laryngeal clefts: a histopathologic study and review.

The histopathologic findings in a case of laryngeal cleft studied by serial sectioning, and a literature review of this clinical entity are presented. The primary micropathologic findings include a cleft deformity of the posterior cricoid lamina, and alterations in muscle differentiation involving the interarytenoid and posterior cricoarytenoid muscles. Possible embryogenic mechanisms are discussed. The clinical picture is characterized by signs and symtpoms of aspiration with airway obstruction, and definitive diagnosis is achieved by endoscopic examination. Treatment consists of surgical repair, although some patients with type 1 laryngeal clefts may be managed on a conservative trial. The need for uniform classification of laryngeal clefts in future reporting is emphasized.

Congenital Abnormalities↗
PubMedDate not supplied

Vestibular and optokinetic responses of the white cat.

The vestibular and optokinetic responses of a group of white cats were evaluated and compared with the responses from a control group of pigmented animals. The results indicate that in all cases the white cats exhibited varying degrees of vestibular and/or optokinetic dysfunction, which in some animals varied from test session to test session.

Animals↗