VALUE OF SONOGRAPHY IN THE DIAGNOSIS OF INTRACRANIAL HEMORRHAGE AND PERIVENTRICULAR LEUKOMALACIA - A POSTMORTEM STUDY OF 35 CASES

Periventricular leukomalacia and germinal matrix hemorrhages are major causes of neurodevelopmental abnormalities in the premature neonate. Although sonography is widely used to detect these abnormalities and is thought to be sensitive for hemorrhages and the later cystic stages of periventricular leukomalacia, its sensitivity for the more acute phase of periventricular leukomalacia remains to be determined. It has been difficult to study this issue because periventricular leukomalacia often is not lethal, and in postmortem studies there is usually a considerable interval between the time of in vivo imaging, if any, and the death of the patient. A 'prospective' autopsy study was performed on brain specimens from infants who died at less than 1 year of age during a 10-month period. Thirty-five formalin-fixed brains were studied and sonographic images of these specimens were compared with histologic findings in whole brain sections to determine the sensitivity and specificity of sonography for the detection of germinal matrix hemorrhage and periventricular leukomalacia. Sonography identified germinal matrix hemorrhages as small as 5 mm, although smaller lesions were not visualized. Postmortem sonography had a sensitivity of 27% and specificity of 88% for all germinal matrix hemorrhages, but a sensitivity of 100% and specificity of 91% for hemorrhages larger than 5 mm. Periventricular leukomalacia, seen as hyperechoic areas in the periventricular white matter, was not detected as readily. For periventricular leukomalacia, the overall sensitivity and specificity were 50% and 87%, respectively. We conclude that sonography is useful for detecting the larger germinal matrix hemorrhages, but has more limited sensitivity in the early diagnosis of periventricular leukomalacia.