The relationship between the degree of chronic middle ear inflammation and tympanic bulla pneumatization in the pig as animal model.
The relationship between the degree of chronic middle ear inflammation and pneumatization was investigated in the pig as an animal model, since its tympanic bulla closely resembles the human mastoid air cell system. Ten piglets (sire: Landrace-Hampshire crossbreed; dam: Duroc) were used for this experiment. Four ears of two animals served as the normal control group and 16 ears of eight animals were the experimental group. In this latter group, otitis media was induced by injecting glycerin into the middle ear clefts 1 months after birth, and the degree of inflammation was varied by administering or withholding antibiotics (cefamandole and dibekacin) and adjusting the dosage regimen. The animals were sacrificed 6 months after birth and examined for the relationship between the degree of chronic middle ear inflammation present and tympanic bulla pneumatization. Various degrees of inflammation were successfully induced by injecting the antibiotics: the more severe the inflammation found, the greater was the inhibition of pneumatization. Findings demonstrated that the degree of inhibition of pneumatization produced was directly proportional to the severity of chronic middle ear inflammation.
Department of Otolaryngology, Niigata University School of Medicine, Japan.
F
F
Ikarashi
Y
Y
Nakano
T
T
Okura
D000818:Animals; D001862:Bone Resorption / Q000473:pathology; D002435:Cefamandole / Q000008:administration & dosage / Q000627:therapeutic use; D002908:Chronic Disease; D003982:Dibekacin / Q000008:administration & dosage / Q000627:therapeutic use; D004195:Disease Models, Animal; D004432:Ear, Middle / Q000187:drug effects; D004848:Epithelium / Q000473:pathology; D005990:Glycerol / Q000009:adverse effects; D007091:Image Processing, Computer-Assisted; D007273:Injections, Intramuscular; D010006:Osteoblasts / Q000473:pathology; D010010:Osteoclasts / Q000473:pathology; D010026:Osteosclerosis / Q000473:pathology; D010033:Otitis Media / Q000139:chemically induced / Q000188:drug therapy / Q000503:physiopathology*; D013552:Swine; D013701:Temporal Bone / Q000254:growth & development / Q000473:pathology*
D003982:Dibekacin; D002435:Cefamandole; D005990:Glycerol