Monostotic fibrous dysplasia of the temporal bone

Abstract

Fibrous dysplasia is a rare but interesting benign condition of the bones which affects either a single bone or multiple bones, with or without endocrine abnormalities. Only 75 cases affecting the temporal bone have been reported in the world literature, and to these we add another case. Although systemic involvement in the form of endocrine abnormalities and skin pigmentation has been reported in the past, no case has yet been reported with a congenitally absent kidney in the monostotic form of the disease.

Fibrous Dysplasia of the Temporal Bone: Reversal of Sensorineural Hearing Loss After Decompression of the Internal Auditory Canall

“…Fibrous dysplasia is a slowly progressive disease that can affect all bones of the body. There have been 76 cases of fibrous dysplasia affecting the temporal bone reported in the literature 7 . A total of nine cases of sensorineural hearing loss secondary to fibrous dysplasia have been reported 2 .…”

“…Fibrous dysplasia is a benign disease in which there is slowly progressive growth of abnormal fibroosseous tissue which displaces the normal medullary bone. The tissue contains disorganized bony trabeculae and spindle cells surrounded by a fibrous matrix 2,5‐7 . Theories of etiology for this disease include aberrant differentiation of mesenchyme during bone formation, an arrest of bone at the immature woven stage, or a disturbance of cancellous bone maintenance 8 .…”

Asymptomatic fibrous dysplasia of the temporal bone

“…6 Yaunus and Haleem 7 reported an infant case in a nine months old with an absent kidney. 4,7 Theories of the aetiology of this disease include aberrant differentiation of the mesenchyme during bone formation, an arrest of bone at the immature woven stage or a disturbance in cancellous bone maintenance. 2 This disease has a racial predominance, in that Caucasians account for >80 per cent of all cases, African-Americans 2 per cent and Asians only 1 per cent.…”

“…5,7,14 The disease process usually stops at puberty. The decision to treat depends on the degree of cosmetic or functional impairment.…”

Displasia fibrosa do osso temporal: relato de dois casos

“…O osso temporal esta comprometido em somente 18% dos casos de DF, ocorrendo mais freqüentemente em associação com as formas monostóticas do que poliostóticas. 11 Em relação à patofisiologia, enquanto a maioria das autores acreditam que a displasia fibrosa monostótica (DFM) representa uma anormalidade congênita da formação óssea mesenquimatosa, o seu modo de transmissão (autossômico-dominante ou recessivo) é ainda um tópico em debate. 6 Outras teorias da patogênese da DFM são menos valorizadas.…”