Cerebellar hemorrhage complicating isovaleric acidemia: a case report.

Isovaleric acidemia (IVA) is an inborn error of leucine metabolism, resulting in an accumulation of isovaleric acid in the body fluids. The neuropathologic findings in an 11-day-old infant with IVA consisted of diffuse cerebral edema, massive cerebellar hemorrhage, upward transtentorial herniation, and focal degeneration of clusters of glial cells in white and gray matter. Although abnormal myelination has been described in different aminoacidopathies, the above findings have not been reported previously in IVA.

Intracranial hemodynamics in sleep apnea.

Intracranial pressure changes and poor cerebral perfusion have been reported in sleep apnea syndrome (SAS), but such studies have been limited due to lack of a reliable noninvasive study method. We determined the systolic (VS), diastolic (VD), and mean (VM) cerebral blood flow velocities of the middle cerebral artery in 23 individuals (12 severe SAS patients and 11 control subjects) using transcranial Doppler sonography before sleep, during sleep (NREM and REM) and upon awakening. All three velocities (VS = 87.4 cm/s compared to 104.7 cm/s, VD = 41.6 cm/s compared to 47.7 cm/s, and VM = 57.0 cm/s compared to 67.0 cm/s) were decreased in patients with SAS and VS and VM were significantly lower than in control subjects (p = 0.005 and p = 0.033, respectively). The end-tidal CO2 (PETCO2) in the SAS patients (47.3 mm Hg) compared to the control subjects (41.8 mm Hg) was significantly higher (p = 0.003). When the VM was adjusted to normalized CO2 using the Markwalder's equation, the reduction in velocity in patients with SAS (47.5 cm/s) compared to control subjects (63.0 cm/s) became more significant (p = 0.005). This study shows that cerebral blood flow velocities are lower in patients with SAS compared to control subjects and that transcranial Doppler sonography may be useful in such evaluations.

The use of ultrasound in evaluating neurologic diseases of childhood.

Real-time cranial sonography, intracranial Doppler, and neuromuscular sonography are the sonographic techniques that are applicable to the neurologic evaluation of infants and children. Although limited by age, specificity, and operator skill and experience, the advantages of real-time cranial and intracranial Doppler sonography make them useful techniques in the evaluation of the young infant, particularly in the serial assessment of ventricular size and in the study of the critically ill infant. The use of neuromuscular sonography in the assessment of the floppy infant and in the guidance of biopsy makes this an increasingly valuable tool.

Computerized real-time neuromuscular sonography: a new application, techniques and methods.

Diagnostic ultrasound has been extensively used for neurologic evaluation of cranial, vascular and spinal diseases. This study presents the techniques, methodology, and procedures for a new diagnostic application of ultrasound for evaluation of the neuromuscular system. In order to determine the optimum sonographic characterization of neuromuscular disease, normal anatomy has to be studied with ultrasound to develop a reproducible standardized methodology for routine use of ultrasound in neuromuscular imaging. To fulfill this objective, 30 subjects between the ages of 1 day and 59 years were studied with computerized real-time sonography. The results of this study are presented with illustration of the sonographic images of transverse and longitudinal planes of the upper and lower limbs. Computerization of optimum sonographic techniques, gradation of normal sonographic muscle anatomy by age, and elimination of operator variability were goals that were accomplished, thereby setting the stage for reliable, reproducible muscle imaging by ultrasound.

Transcranial Doppler and real-time cranial sonography in neonatal hydrocephalus.

Nine hydrocephalic infants who were less than 1 year old and 7 age-matched control subjects were examined by real-time and transcranial Doppler sonography to evaluate cerebral blood flow and to correlate it to ventricular size. These 16 infants were placed in one of three groups: infants in group 1 (n = 7) had a normal ventricular size, infants in group 2 (n = 3) had a progressively increasing ventricular size, and infants in group 3 (n = 6) had ventriculomegaly with either stable or decreasing ventricular size or a functioning ventriculoperitoneal shunt. All scans performed on group-2 infants showed markedly increased ventricular size and increased pulsatility index, while those on group-1 infants showed a normal ventricular size and pulsatility index. However, the scans of group-3 infants revealed increased ventricular size and pulsatility index for all groups. Regression analysis of the data showed rather weak correlations between ventricular size and pulsatility index for all groups. The regression data suggest that ventricular size is not the main determinant of cerebral blood flow in the neonate with hydrocephalus and that intracranial pressure may be a more critical factor. These data suggest that pulsatility index, as measured by transcranial Doppler, can be clinically more important than just the anatomical data alone in the evaluation of hydrocephaly. This points to a possible use of transcranial Doppler sonography in the evaluation of hydrocephalic patients for placement of ventriculoperitoneal shunts.

Transcranial Doppler: a noninvasive method to monitor hydrocephalus.

The ability to discriminate between ventriculomegaly and hydrocephalus often relies on clinical impression and parameters such as change in ventricular size and configuration, increasing head circumference, and evidence of developmental delay. In an effort to confirm clinical impressions, 24 children underwent transcranial doppler (TCD). All had ventriculomegaly confirmed by computerized cranial tomography (CT), magnetic resonance imaging (MRI), and/or cranial ultrasound (CS). Fifteen were infants and nine were older children with closed fontanelles. Three patient groups were established. Group 1 included those patients with ventriculomegaly but no clinical evidence of increased intracranial pressure. Group 2 included those children with hydrocephalus and evidence of increased intracranial pressure. The last group consisted of hydrocephalic children who had shunts placed for increased pressure. The Gosling pulsatility index (PI) as well as the peak systolic velocity (PS) as measured by the TCD were compared in all three groups. The PI was found to be a useful indicator of increased intracranial pressure and need for eventual shunt. Transcranial doppler sonography may therefore prove useful as a noninvasive, easily reproducible screening tool to evaluate children with hydrocephalus.

The effect of sleep on intracranial hemodynamics: a transcranial Doppler study.

The effect of sleep on intracranial blood flow velocities has not been reported in children or adults, even though blood flow velocities are evaluated for clinical purposes during both sleep and wakefulness. We report the effect of sleep on intracranial blood flow velocities of 11 healthy individuals (five children and six adults) who were monitored by polysomnography and transcranial Doppler sonography (TCD). Thirty-three TCDs were obtained on middle cerebral arteries. Before sleep, during non-rapid-eye-movement sleep, and after sleep, measurements of systolic, end diastolic, and mean flow velocities were obtained by TCD. Pulse oximetry and end tidal carbon dioxide were monitored during each 8-hour polysomnogram. The before-sleep blood flow velocity values were compared to sleep and after-sleep values in children and adults separately using ANOVA. A significant decrease in the blood flow velocities was noted during sleep compared to before-sleep values in both children (P less than .05) and adults (P less than .01). The blood flow velocities after sleep were also decreased compared to before-sleep values. This study shows that sleep reduces blood flow velocities in both children and adults. A decrease in blood flow velocities during normal sleep should be taken into account when interpreting TCDs in patients.

The evolution of ischemic cerebral infarction in infancy: a sonographic evaluation.

Cranial sonography provides a noninvasive, portable method for imaging the infant brain. This study describes the time-dependent, sonographic findings of infantile cerebral infarction, as well as computed tomographic (CT) scan and neuropathologic confirmation. Three hundred ninety-five infants under 18 months of age were sonogrammed over a period of 18 months. Three infants were diagnosed by cranial sonography and confirmed by CT scan and/or autopsy to have acute ischemic cerebral infarcts. The cases were followed with serial cranial sonograms for up to 18 months of age. The acute sonographic findings included a hyperechoic zone around the infarcted tissue. The subacute infarct had a checkerboard pattern, while the chronic infarcts were anechoic.

Joubert syndrome: early diagnosis by recognition of the behavioral phenotype and confirmation by cranial sonography.

Our experience with two children with Joubert syndrome demonstrates how the diagnosis, if suspected by recognition of the behavioral phenotype, can rapidly be made by employing cranial sonography. This technique also may afford prenatal diagnosis of the syndrome in future siblings of confirmed cases. We have produced an educational videotape demonstrating the dynamic behavior of these patients. It is our hope that increased familiarity with the behavior phenotype through this report and through distribution of the videotape will lead to early and accurate diagnosis of further cases of this syndrome.

Comparative neuroimaging with pathologic correlates in Alexander's disease.

We describe a case of pathologically confirmed Alexander's disease in which serial cranial ultrasound studies demonstrated unique findings of enlarging subependymal cysts with evolving periventricular hyperechogenicity. Computed tomographic scan of the head showed low attenuation of the periventricular white matter and centrum semiovale. Magnetic resonance imaging (MRI) demonstrated diffuse, confluent high signal predominantly in frontal white matter. These imaging modalities, particularly cranial ultrasound and MRI, may be useful tools in the diagnostic evaluation of children with degenerative neurologic disease, megalencephaly, and suspected Alexander's disease.

Evaluation of congenital extracranial masses by waterpath sonography.

Congenital scalp masses pose a diagnostic and management challenge. In the past the relationship of the lesion to the skull and intracranial contents have been assessed by skull x-rays and computed cranial tomography. Waterpath sonography is a non-invasive technique that utilizes no ionizing radiation for evaluating and monitoring congenital scalp masses. In two illustrative cases this method of imaging assisted in assessing the size, contents, and relationship of the congenital scalp masses to the intracranial contents. It enabled the surgeon to anticipate the avascular cystic nature of the congenital scalp masses, the intact underlying calvarium, and non-violation of the CSF pathways prior to surgery. The technique was also useful for monitoring progress after surgery.

Citrobacter freundii: a newly reported cause of pyomyositis.

Pyomyositis has been uncommonly reported in temperature climates, but is being recognized with increasing frequency. The most common etiologic agent is Staphylococcus aureus, although other pathogens have been rarely implicated. The authors describe the first case of pyomyositis caused by Citrobacter freundii. Because of the rarity of this disease in North America, it is often initially misdiagnosed. Neuromuscular sonography, a non-invasive imaging technique, identified the muscle abscess in this patient.

Diagnosis of cerebral atrophy in infants by near-field cranial sonography.

Cranial sonography is the ideal imaging tool for use in infants. However, it has not been used for the diagnosis of cerebral atrophy in infants as the subarachnoid space has been a "blind spot" with ultrasound. We evaluated cerebral atrophy by a unique application of cranial sonography that we have termed the near-field method, and compared these results with those of cranial computed tomography (CT). We examined 106 infants with the near-field method of cranial sonography. Eleven patients fitted our sonographic criteria for cerebral atrophy. Cranial CT was done in eight of the 11 patients with sonographic findings of cerebral atrophy and was consistent with the diagnoses of cerebral atrophy in all cases. Of these eight patients, one had cerebral atrophy and subdural effusion seen by both near-field sonography and cranial CT. Cranial CT was performed in eight of the 95 patients with normal sonographic findings, and all results were normal. All patients with cerebral atrophy determined by cranial CT were found to have cerebral atrophy by near-field sonography. Likewise, all patients without cerebral atrophy by cranial CT were not found to have cerebral atrophy CA by near-field sonography. The near-field method of cranial sonography therefore appears to have a sensitivity and specificity of 100% with cranial CT as a referral method.

Muscle imaging in neuromuscular disease using computerized real-time sonography.

The results of a study utilizing computerized real-time sonography (CRS) to image muscles in patients with neuromuscular disease are presented for 67 patients, 37 with neuromuscular disease and 4 with upper motor neuron disease, and 26 age-matched healthy controls between the ages of 2 days and 59 years. CRS is a safe, noninvasive, atraumatic method for evaluating a broad range of neuromuscular diseases. It is capable of differentiating myopathies or dystrophies from neurogenic atrophies and floppy infants with "central" hypotonia from those with neuromuscular diseases.