Meningeal osteomas and chronic renal failure.

Osteomas, although usually found in the frontal and ethmoid sinuses or the mandible, may be located on the inner table of the skull. We report the incidence, distribution, histologic features, and clinical correlates of intracranial osteomas arising in the dura mater and the falx cerebri in 200 consecutive adult autopsies. Ten patients (5 per cent of autopsies) were found to have meningeal osteomas. The tumors were usually located at the dural-falx junction at the superior longitudinal sinus. Histologically, they resembled osteomas arising from other sites, but undecalcified sections generally demonstrated histologic features of active bone remodeling--namely, the presence of abundant osteoid and numerous osteoclasts, and, in some instances, osteitis fibrosa. The age and sex distributions were similar among autopsied patients with meningeal osteomas (mean age, 66 years; 60 per cent female) and those without (mean age, 64 years; 58 per cent female). Although the incidence of uremia in the general autopsy population was only 13 per cent, 60 per cent of patients with osteomas died with concomitant renal failure. The authors consider these cases of meningeal ossifications and reports of meningeal calcifications to represent osteomas arising from the dura mater and the falx cerebri. Thus, intracranial osteomas may be more common than was previously recognized. In some instances, the abnormal biochemical state accompanying chronic renal failure may stimulate new bone formation in the osteogenic tissue of the dura mater.