Monostotic fibrous dysplasia of the temporal bone

THE term fibrous dysplasia was used by Lichtenstein in 1938 with reference to the polyostotic form of the disease. He regarded it as a skeletal developmental anomaly usually jiffecting several or many bones with predominantly unilateral involvement. The cause of the disease is unknown. Lichtenstein and Jaffe (1942) published a paper entitled 'Fibrous dysplasia of bone, a condition affecting one, several or many bones, the graver cases of which may present abnormal pigmentation of skin, premature sexual development, hyperthyroidism or still other extra skeletal abnormalities'. The graver cases referred to in this paper constitute Albright's syndrome. The bony pathology consists of the formation of fibrous tissue within the affected bone. There is a wide variation in the degree of cellularity of this fibrous tissue. Immature bony trabeculae in varying amounts are found scattered throughout, and areas of degeneration and cyst and cartilage formation also occur. The bone is usually expanded but where there is no expansion, the cortex is usually eroded from the medullary side. Involvement of the skull is frequent. Windholz (1947) estimates that there is cranial involvement in 10 per cent ofjnonostotic disease, 50 per cent of cases with, moderate involvement and 100 per cent of the severely affected cases. The monostotic form of the disease was found in 15 out of 87 cases reported by Lichtenstein and Jaffe and 67 out of 69 cases reported by Schlumberger (1946). Five of Schlumberger's cases with monostotic disease involved the calvarium. The frontal bone was involved in 2 instances and the parietal, occipital and temporal bones were each involved in 1 case. The literature now contains a total of 9 reports of monostotic fibrous dysplasia of the temporal bone. Schlumberger reports a 25-year-old male with a history of attacks of otalgia and otorrhoea until the age of 12. Shortly after this age he developed a swelling behind the right ear associated with intermittent otalgia. He was treated by curettage of the mastoid which was found to contain extremely vascular and gritty material with the consistency of dried-out cheese. Sherman and Sternbergh (1948) report a 15-year-old boy who complained of right-sided deafness and swelling behind the right ear. He was treated by curettage of the diseased bone. The histological diagnosis was an ossifying fibroma. No further clinical details are given.