[Relationship between neonatal polycythemia and brain damage].
OBJECTIVE
To investigate the clinical manifestations, imaging characteristics as well as prognosis of neonatal polycythemia complicated with brain damage.


METHODS
One hundred and sixteen in-patients with neonatal polycythemia admitted to our hospital during January 2003 to October 2005 were analyzed. Their clinical manifestations were observed. Craniocerebral ultrasonic examination (2D, 3D), CT and MRI were employed to dynamically observe the craniocerebral imaging variances as well as the cerebral hemodynamic variations and near infrared spectroscopy (NIR) was adopted to test the cerebral oxygenation. Twenty-two cases with moderate or severe disease were followed up for 3 to 12 months.


RESULTS
Out of the 116 polycythemic neonates, 53 cases had brain damages, of whom 31 had mild, 14 had moderate, and 8 had severe damages. Cranial imaging alterations were mostly ischemic injuries of various areas of different severity. The severity of brain damage was closely related to the duration of polycythemia, oxygen saturation of cerebral tissues as well as cerebral hemodynamic abnormalities. Brain injury was likely to occur in those whose polycythemia persisted for more than three days. The regional saturation of oxygen (rSO(2)) in mild brain injury cases was found to be 52.1%, while it was 47.1% in moderate and severe brain injury cases. Compared to the 58% as found in non-brain injury cases, the variance was found to be statistically significant (F = 104.466, P < 0.01). Among the cases with brain injury, cerebral hemodynamics displayed a slowdown in the blood flow velocity in the cerebral anterior artery and medium artery during the systolic phase and/or the diastolic phase. The abnormality ratio was closely related to the severity of brain injury. Through the chi(2) test the variance was proved to be statistically highly significant (chi(2) = 18.889, P < 0.01), however it was not correlated with the increase of the initial levels of hemoglobin (Hb) and hematocrit (HCT) (P > 0.05). During the follow up, neurological developmental abnormalities of various severity were found to exist in the cases with moderate (5/12) and severe disease (7/8), while cerebral palsy or epilepsy was not yet found.


CONCLUSIONS
Neonatal polycythemia might tend to bring about a reduction in the perfusion of cerebral blood flow and damaged cerebral oxygenation metabolism which in turn might lead to cerebral ischemic injury, which in some of the moderate and severe cases might lead to long-term neurological complications. Imaging investigations especially craniocerebral ultrasonic examination could be the practical means for the early diagnosis and evaluation of prognosis.
Tang
Ze-zhong
ZZ
Department of Pediatrics, First Hospital, Peking University, Beijing 100034, China.
Zhou
Cong-le
CL
Wang
Hong-mei
HM
Hou
Xin-lin
XL
Liu
Yun-feng
YF
Jiang
Yi
Y
D001921:Brain / Q000473:pathology; D001925:Brain Damage, Chronic / Q000150:complications*; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases; D008279:Magnetic Resonance Imaging; D008297:Male; D011086:Polycythemia / Q000150:complications*; D012886:Skull / Q000000981:diagnostic imaging; D015898:Tomography Scanners, X-Ray Computed; D014463:Ultrasonography