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Biomedical subjects

B W Jafek

Publications and source records attributed to B W Jafek.

At least 37 records · Page 2Linked to original sources
PubMed1991

Intrinsic vasculature of the labyrinthine segment of the facial nerve--implications for site of lesion in Bell's palsy.

Recent studies of the intrinsic vasculature of the cat facial nerve have demonstrated relatively poor blood supply to the labyrinthine segment. In this study, the intrinsic vasculature of the human facial nerve was systematically evaluated in 25 temporal bones and three fresh cadaver nerves. Cross-sectional vessel counts were obtained for the labyrinthine, tympanic, and mastoid segments. Capillary densities for each segment were derived from these data. The labyrinthine segment of the human facial nerve, like that in the cat, contains fewer and smaller intrinsic blood vessels than do the mastoid and tympanic segments. This may indicate that the labyrinthine segment of the facial nerve may be more vulnerable to ischemic damage. In conjunction with the previously demonstrated narrowness of the labyrinthine fallopian canal, these findings support the contention that the labyrinthine segment is a likely site of lesion in Bell's palsy.

Ear, Inner↗
PubMed1991

The intraoperative management of the thyroid gland during laryngectomy.

The standard of care of laryngeal cancer surgery is wide field excision of the larynx combined with ipsilateral thyroid lobectomy. A retrospective review of 247 laryngectomies performed between 1979 and 1989 was undertaken to determine specific intraoperative indications for thyroid gland removal. The incidence of thyroid disease in our patients with laryngeal cancer was compared to the normal population. Eight percent of thyroid specimens removed during laryngeal cancer surgery demonstrated invasion by squamous cell carcinoma. All patients having thyroid invasion had T3 or T4 laryngeal lesions that were stage IV at the time of surgery. All these lesions were found to have transglottic growth and laryngeal cartilage invasion by the pathologist. All of these patients also had abnormal thyroid glands intraoperatively and laryngeal cartilage destruction that was evident intraoperatively. Total thyroidectomy with bilateral paratracheal and pretracheal lymph node dissection is indicated when squamous cell carcinoma of the larynx involves the thyroid gland. Prophylactic ipsilateral thyroid lobectomy and isthmusectomy is warranted for large laryngeal cancers (T3, T4) that involve the anterior commissure, the subglottic area, or extend transglottically. Routine thyroid gland removal is not indicated for the majority of laryngeal cancers that do not meet the aforementioned criteria. Finally, abnormal thyroid histopathology was diagnosed in 37% of the surgical thyroid gland specimens removed during laryngectomy.

Adenocarcinoma↗
PubMed1990

The effect of chronic cocaine abuse on human olfaction.

Cocaine has been used for many decades as both a stimulant and as a topical anesthetic/vasoconstrictor. Illicit "snorting" or freebase smoking has increased markedly in recent years. Decreased olfaction has been an often reported subjective complaint of cocaine abusers, but quantification of smell loss using sensitive psychophysical tests has not yet been done, leading to the present study. Eleven cocaine abusers were recruited from a drug treatment clinic. Olfaction was assessed using a butanol threshold test, the UPSIT, and a 7-item discrimination test. One patient tested anosmic, one had a mild discrimination problem, and one had a large septal perforation but was normosmic. From the present study, it appears that most cocaine abusers, even heavy users or those with intranasal damage, do not develop permanent olfactory dysfunction. It is not clear what factors may have resulted in complaints of olfactory loss in previous studies.

Adult↗
PubMed1990

Congenital anosmia.

Seven patients with congenital anosmia underwent detailed chemosensory evaluation, followed by the performance of biopsies of the olfactory region. Olfactory epithelium was not found in any of the biopsy specimens. It appears therefore that patients with congenital anosmia lack any olfactory epithelium. Several possible explanations for this finding are discussed. The most attractive hypothesis is that the olfactory placode forms either normally or abnormally during development but later degenerates and is replaced with respiratory epithelium. Only one patient in our series had congenital anosmia in association with a syndrome (Kallmann's syndrome), indicating that congenital anosmia is found more often as an isolated symptom.

Adolescent↗
PubMed1989

Peroxidase backfills suggest the mammalian olfactory epithelium contains a second morphologically distinct class of bipolar sensory neuron: the microvillar cell.

The olfactory epithelium of man, rat and some other mammals consists of 4 cell types: ciliated olfactory receptors, microvillar cells, supporting (sustentacular) cells, and basal cells. Of these, the microvillar cell is least well understood: its function is unknown. In this study, a hypothesis is put forth: that the microvillar cells in the mammalian olfactory epithelium comprise a morphologically distinct class of sensory receptor. The hypothesis is tested by injecting the cytochemical tracer macromolecule horseradish peroxidase (HRP) into the olfactory bulb of the rat, and observing its pattern of uptake in the olfactory epithelium by light and electron microscopy. In these experiments, ciliated olfactory receptors and microvillar cells backfilled with HRP: supporting and basal cells did not. The data, which support the hypothesis, indicate the microvillar cells, along with the ciliated olfactory receptors, send axons to the olfactory bulb. Consequently, it is concluded that the microvillar cell is a sensory bipolar neuron, with the cell body in the olfactory epithelium, that sends a dendrite to the site of stimulus reception at the free surface of the olfactory epithelium, and an axon to the olfactory bulb in the brain. The similarity of microvillar cells in the olfactory epithelium to 'brush cells' found throughout the respiratory tract is discussed in detail.

Animals↗
PubMed1989

Post-traumatic anosmia. Ultrastructural correlates.

Five patients suffering post-traumatic anosmia were studied at the University of Colorado Health Sciences Center, Denver. Each patient underwent psychophysical testing, clinical evaluation, and olfactory biopsy. The biopsy specimens were examined ultrastructurally and were found to vary from normal tissues. The overall appearance of the olfactory epithelium in the post-traumatic patient is disrupted and the receptor cells are distorted. Large numbers of axons are located near the basement membrane and can often be found in bundles throughout the epithelium, extending even to the mucosal surface. Olfactory cilia are rarely seen in epithelia obtained from post-traumatic patients. Bald olfactory vesicles, often containing basal bodies, are frequently observed. We postulate that in these cases, the olfactory epithelium regenerates following head trauma and the receptor cells attempt to send axons centrally. However, the cribriform plate has undergone fibrotic healing and the axons are unable to penetrate it and make contact with olfactory bulb neurons.

Adult↗
PubMed1989

Oral evaluation of patients with chemosensory disorders.

The physical examination of the patient with dysgeusia must include a thorough intraoral examination. Although the initial screening examination may be performed by clinicians of various disciplines, specialized intraoral or dental examination may be required to diagnose and manage the dysfunction.

Dysgeusia↗
PubMed1989

Surgical management of chemosensory disorders.

As additional understanding of the histopathologic basis of chemosensory dysfunction has been achieved, several actual and potential surgical approaches for correction have been devised. These currently include correction of steroid-dependent anosmia and hyposmia due to septal deviation. Posttraumatic anosmia might be correctable in the future. Surgical approaches to dysgeusia are sparse, probably due to a paucity of information on the causes of this disorder.

Humans↗
PubMed1989

Initial otolaryngologic assessment of patients with taste and smell disorders.

Patients are often referred to otolaryngologists to evaluate dysfunctions of taste or smell. A history and physical examination focused on signs and symptoms of chemosensory disorders, in combination with screening tests for taste and smell function, can quickly and easily delineate the general type and cause of the dysfunction. Several centers for chemosensory disorders referred to in this issue are available for referral to patients who need detailed testing and evaluation. Although treatment options for most taste and smell dysfunctions are limited, by categorizing disorders, we can give the patient an idea of the probable cause and prognosis of the dysfunction.

Humans↗
PubMed1987

Steroid-dependent anosmia.

In steroid-dependent anosmia (nasal polyps, inhalant allergy, anosmia), high doses of steroids will temporarily restore the sense of smell, a diagnostic test. Appropriate surgery can then be carried out, followed by low-dose, long-term steroid therapy to maintain the sense of smell. Olfactory biopsy specimens taken during the course of evaluation and treatment show electron-optically normal olfactory receptors, meaning that the probable pathogenesis of the sensory deficit is an obstruction, mechanical and possibly biochemical. Two cases of steroid-dependent anosmia are presented to detail a fully reversible anosmia using state-of-the-art techniques.

Adrenal Cortex Hormones↗
PubMed1987

Diagnostic imaging of Waldeyer's ring.

Diagnostic imaging of Waldeyer's ring can be obtained by plain films, CT scans, and MRI. In most instances, physical examination and plain films are sufficient for diagnosis and therapy. In addition, plain films are inexpensive and readily available. Although more expensive and less available, CT and MRI allow further evaluation of deep tissues not seen by physical examinations and plain film and permit more complete evaluations of more complex pathologic processes in Waldeyer's ring. Although both CT and MRI are often complementary, the indications for each modality are still evolving.

Adenoids↗
PubMed1987

Who operated on Max?

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Hospital Departments↗
PubMed1986

Laryngeal dysfunction and pulmonary disorder.

The normal respiratory function of the larynx has been described in detailed reports in both the otolaryngology and the respiratory physiology literature. The role of the posterior cricoarytenoid muscle in vocal cord abduction has been shown to be paramount in laryngeal respiratory function. However, only in recent reports has attention been directed toward disordered laryngeal function as evidenced in pulmonary disorders, such as asthma, or in association with underlying pulmonary disorders, such as asthma (ROAD) or emphysema (COPD). In this article, cases will be presented to demonstrate the role of disordered laryngeal function appearing as pulmonary disease and associated with various degrees of underlying pulmonary disease. The effect on pulmonary function tests and the role of treatment will be discussed.

Adult↗
PubMed1986

What's your PPI?

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Cost Control↗