PubMed Health⌕ Search

Biomedical subjects

R A Chole

Publications and source records attributed to R A Chole.

114 records · Page 7Linked to original sources
PubMedDate not supplied

Ultrastructure of middle ear mucosa in the Mongolian gerbil, Meriones unguiculatus.

The Mongolian gerbil is an easily maintained rodent which has been useful for investigations of the middle and inner ear. The gerbil may be used as an animal model for otitis media and cholesteatoma. The purpose of this study was to describe the ultrastructure of the epithelial and subepithelial lining of the gerbilline middle ear. The middle ear of the gerbil is lined by an epithelial membrane which is similar in cell type to human and guinea pig middle ear mucosa. The major part of the middle ear is lined with simple, non-keratinizing squamous cells with or without microvilli. Ciliated and secretory cells were concentrated around the Eustachian tube orifice; additionally, ciliated cells were seen in two distinct bands extending posteriorly below the cochlea in the hypotympanum and above the cochlea toward the tensor tympani muscle. The subepithelial region consists of fusiform cells (fibroblasts or 'surface osteocytes') and collagen adjacent to bone. These cell types and their distribution further supports the use of the gerbil as a model for human disease.

Animals↗
PubMedDate not supplied

Petrous apicitis: surgical anatomy.

Various surgical approaches to the petrous apex for exposure and drainage of suppurative processes are available to the otologist. The petrous apex may be conveniently divided into anterior and posterior portions by a line in the coronal plane through the internal auditory canal. The approach to the posterior petrous apex follows fistulous tracts in the sinodural angle, the subarcuate fossa, and the infralabyrinthine tract. The anterior petrous apex may be entered by means of a radical mastoidectomy. Fistulous tracts into an infected anterior petrous apex may be found through the hypotympanum, below the cochlea, through a triangle anterior to the cochlea, below the middle fossa dura, and above the carotid artery. In this approach to the petrous tip, one must have a thorough knowledge of the anatomical relationships around the carotid artery and cochlea: the carotid artery lies within 1.69 +/- 0.70 mm of the cochlea anteriorly, and the carotid artery may be exposed within the middle ear.

Drainage↗
PubMedDate not supplied

Ossicular and otic capsular lesions in LP/J mice.

Otosclerosis is an inherited disease in which abnormal bone growth results in ossicular fixation and hearing loss. Although the disease affects up to 10% of humans, it has not been observed in other animals. The LP/J inbred mouse has been found to develop abnormal bony lesions of the middle ear which resemble human otosclerosis. In this study of 113 temporal bones from LP/J mice, we found that the lesions develop after puberty and involve only the ossicles and the otic capsule. The most frequent site of involvement was the incus (46.9%), followed by the anterior crus of the stapes (31.3%), the malleus (14.2%), the otic capsule (14.2%), and the stapes footplate (8%). Cochlear hair cell loss was progressive throughout the lifespan of these animals. Although this disease is not identical in histologic appearance to human otosclerosis, understanding its disease process may shed light upon the pathophysiology of the human disease.

Animals↗
PubMedDate not supplied

The diagnosis and treatment of scrofula (mycobacterial cervical lymphadenitis).

Mycobacterial cervical lymphadenitis, or scrofula, may be caused by Mycobacterium tuberculosis, or the atypical mycobacteria. It is important to distinguish between tuberculous cervical lymphadenitis and atypical mycobacterial cervical lymphadenitis, since medical and surgical treatment of each of these entities is different. The two types of scrofula are compared and contrasted. The appropriate treatment of each is discussed, and the complications of improper management are described.

Adult↗