We attempted to reproduce the work of Naeye with regard to the thickness of the muscular media in small pulmonary arteries among victims of the sudden infant death syndrome, using Naeye's methods. In two separate studies, using two slightly different groups of patients and different ocular grids, we observed a statistically significant difference between crib deaths and accidental deaths in hyperplasia of the arterial muscular media, the only parameter not dependent on point-counting. As no investigator has been able to achieve exactly the same results as Naeye in all three parameters, we concluded that point-counting is probably not the method of choice for this determination. Our data for hyperplasia (in the second phase of the study) correlated with those for the retention of periadrenal brown fat and hepatic erythropoiesis in the same patients.