IN 1964, Landing et al 1 established neurovisceral lipidosis as a clinicopathological entity. The same disease has also been called generalized gangliosidosis, 2-7 systemic lipidosis, 8-11 G M1 -gangliosidosis, 3,12-18 familial amaurotic idiocy with visceral involvement, 19,20 biochemically special form of amaurotic idiocy, 21,22 and Landing disease. 5,14,17,23 The disease is characterized by generalized accumulation of a monosialoganglioside, G M1 (ganglioside nomenclature of Svennerholm 24 ), and visceral accumulation of keraton sulfate-like mucopolysaccharide. 12,18 Enzymatically, deficiency of β-galactosidase has been demonstrated in various organs. 4,5,7,14,16-18,23,25,26 From the clinical viewpoint, there appear to be two subtypes. 10 Patients in the age category often exhibit abnormal facies, full forehead, and radiologically detectable bony changes reminiscent of Hurler's syndrome. On the other hand, some older patients in the late infantile age group show few or no clinical or radiologie signs of Hurler's syndrome. The present study was