technetium-tc-99m-exametazime and Infant--Newborn--Diseases

In infants who have experienced prenatal or perinatal injury, it is often difficult, on the basis of clinical examination and conventional investigations (electroencephalogram, cranial ultrasound scan), to diagnose those with brain damage and to predict the type and the severity of subsequent neurological handicaps. We investigated the predictive value of 99mTc-HMPAO brain SPECT performed in the first weeks of life in high-risk neonates. Right-left asymmetries in tracer uptake had no predictive value, regardless of their localization or severity. On the other hand, a change in antero-posterior rCBF distribution was found in 7/10 of neonates with adverse outcome (death, major neurological sequelae) and in none of the 78 neonates with no major motor neurological sequelae. Compared to conventional investigations, 99mTc-HMPAO brain SPECT did not provide additional predictive information when neurological examination, electroencephalogram and cranial ultrasonography were all normal or all abnormal. Conversely, in the 30 patients with anomalies on one or two of the above investigations, SPECT showed an abnormal antero-posterior pattern in 4/6 neonates with major neurological sequelae and no change in the antero-posterior rCBF distribution in the 24 infants who developed normally. In conclusion, our results suggest that 99mTc-HMPAO brain SPECT, when performed in the first weeks of life, can be useful in high-risk neonates to predict occurrence of major neurological handicaps. Because of the relative invasive character of HMPAO scan in neonates and the overall accuracy of the noninvasive tests, radionuclide examination should not be performed in every high-risk neonate. According to our results, 99mTc-HMPAO brain SPECT might be indicated in those children where noncongruent results were obtained with conventional studies.

Topics: Cerebral Palsy; Humans; Infant, Newborn; Infant, Newborn, Diseases; Infant, Premature, Diseases; Organotechnetium Compounds; Oximes; Predictive Value of Tests; Risk; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Neonatal seizures can be difficult to classify according to partial versus generalized onset on the basis of clinical appearance or electroencephalography (EEG). Single-photon emission computed tomography has proven to be useful in adults when adjunctive tests are needed to identify the nature of seizure onset. Although its use has been extended recently to children, the lower age limit at which this technique is useful remains to be established. A case is reported in which ictal Tc-99m HMPAO SPECT of a 16-day-old infant revealed an area of focal hypermetabolism in the right temporal lobe corresponding to an area of focal atrophy revealed by MRI. The EEG of this infant demonstrated multifocal interictal epileptiform abnormalities and an ictal pattern with a generalized onset. This case indicates that ictal SPECT is a useful tool in the evaluation of even the youngest patients with seizures.

Topics: Electroencephalography; Female; Humans; Infant, Newborn; Infant, Newborn, Diseases; Magnetic Resonance Imaging; Organotechnetium Compounds; Oximes; Seizures; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

This study was designed to rate the clinical value of [123I]iodoamphetamine (IMP) or [99mTc] hexamethyl propylene amine oxyme (HM-PAO) brain single photon emission computed tomography (SPECT) in neonates, especially in those likely to develop cerebral palsy. The results showed that SPECT abnormalities were congruent in most cases with structural lesions demonstrated by ultrasonography. However, mild bilateral ventricular dilatation and bilateral subependymal porencephalic cysts diagnosed by ultrasound were not associated with an abnormal SPECT finding. In contrast, some cortical periventricular and sylvian lesions and all the parasagittal lesions well visualized in SPECT studies were not diagnosed by ultrasound scans. In neonates with subependymal and/or intraventricular hemorrhage the existence of a parenchymal abnormality was only diagnosed by SPECT. These results indicate that [123I]IMP or [99mTc]HM-PAO brain SPECT shows a potential clinical value as the neurodevelopmental outcome is clearly related to the site, the extent, and the number of cerebral lesions. Long-term clinical follow-up is, however, mandatory in order to define which SPECT abnormality is associated with neurologic deficit.

Topics: Amphetamines; Asphyxia Neonatorum; Brain; Female; Humans; Infant, Newborn; Infant, Newborn, Diseases; Iodine Radioisotopes; Male; Muscle Hypertonia; Muscle Hypotonia; Organometallic Compounds; Oximes; Seizures; Technetium; Technetium Tc 99m Exametazime; Tomography, Emission-Computed