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ABSTRACT: PurposeThe purpose of this study was to evaluate the usefulness of analysis of the intensity of radio-frequency (RF) signals in intracranial
ultrasonography of preterm infants.
MethodsTwenty neonatal infants admitted to the neonatal intensive care unit of our hospital were included in this study. Their gestational
age was 33–35 weeks. The studies were performed with a System 5 ultrasound system with 3.0-and 5.0-MHz transducers. The transducer
was placed on the anterior fontanel to obtain images. Regions of interest were determined based on B-mode images and were
positioned at the thalamus, caudate nucleus, cerebral white matter, cerebellum, brain stem, and lateral ventricle. The software
used for analysis of the RF signals was EchoMAT (Vingmed Ultrasound).
ResultsThe RF signals of the ventricle and the choroid plexus showed the lowest and the highest intensities, respectively. The intensities
of the brain stem and vermis signals were the same, and were higher than the intensity of the cerebellar hemisphere. The thalamus
and caudate nucleus showed macroscopically identical brightness levels; however, the intensity of the thalamus was lower than
that of the caudate nucleus. The intensity of subependymal hemorrhage was lower than that of the caudothalamic groove. The
intensity of subependymal cyst was the same as that of the lateral ventricle. The RF signal frequencies and intensities were
distinctive in each tissue.
ConclusionThe results of this study suggest that measurement of RF signal intensity may be useful to differentiate macroscopically similar
lesions.
Journal of Medical Ultrasonics 04/2012; 35(2):57-61. · 0.33 Impact Factor
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ABSTRACT: The ratio of the peak transmitral velocity during early diastole (E) to the peak mitral valve annular velocity during early diastole (E') obtained by tissue Doppler imaging correlates with the left ventricular end-diastolic pressure in adults. However, the E/E' ratio has not been established in normal children. The purpose of this study was to assess the effect of age on the various tissue Doppler indices of ventricular diastolic function.
The subjects in this study included 174 children with normal cardiac function. The left and right ventricular inflow velocities were recorded, and the peak of late diastolic flow velocities (A), E, and the ratio of E/A were determined. The following tissue Doppler indices were obtained: peak velocities of early and late diastolic mitral annulus in the left ventricular lateral wall (E'l and A'l) and in the interventricular septum (E'se and A'se) and those of the lateral tricuspid annulus in the right ventricle, E'r and A'r.
The E'l and the E'se increased with age up to 5 years after birth, after which they became constant. The E'r was constant after birth. The E'l/A'l and E'se/A'se increased with age up to 5 years after birth, after which they became constant. The E'r/A'r was constant after birth. The Em/E'se and Em/E'l decreased with age up to 5 years after birth, after which they became constant. The Et/E'r was constant after birth.
The age-related changes suggest age-related alterations in left ventricular diastolic function. Right ventricular diastolic function is constant after birth.
Echocardiography 01/2011; 28(1):93-6. · 1.24 Impact Factor
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ABSTRACT: The molecular pathogenesis of ASD (autism spectrum disorder), one of the heritable neurodevelopmental disorders, is not well understood, although over 15 autistic-susceptible gene loci have been extensively studied. A major issue is whether the proteins that these candidate genes encode are involved in general function and signal transduction. Several mutations in genes encoding synaptic adhesion molecules such as neuroligin, neurexin, CNTNAP (contactin-associated protein) and CADM1 (cell-adhesion molecule 1) found in ASD suggest that impaired synaptic function is the underlying pathogenesis. However, knockout mouse models of these mutations do not show all of the autism-related symptoms, suggesting that gain-of-function in addition to loss-of-function arising from these mutations may be associated with ASD pathogenesis. Another finding is that family members with a given mutation frequently do not manifest autistic symptoms, which possibly may be because of gender effects, dominance theory and environmental factors, including hormones and stress. Thus epigenetic factors complicate our understanding of the relationship between these mutated genes and ASD pathogenesis. We focus in the present review on findings that ER (endoplasmic reticulum) stress arising from these mutations causes a trafficking disorder of synaptic receptors, such as GABA (gamma-aminobutyric acid) B-receptors, and leads to their impaired synaptic function and signal transduction. In the present review we propose a hypothesis that ASD pathogenesis is linked not only to loss-of-function but also to gain-of-function, with an ER stress response to unfolded proteins under the influence of epigenetic factors.
Cell Biology International 01/2010; 34(1):13-9. · 1.48 Impact Factor
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ABSTRACT: A case of cerebral hemorrhage associated with sildenafil (Revatio) use in an infant is presented. Sildenafil is increasingly used in the treatment of primary and secondary pulmonary arterial hypertension and pulmonary arteriovenous fistula. In the reported case, sildenafil used to treat pulmonary arteriovenous fistula improved right-to-left shunting across the pulmonary fistula but resulted in cerebral hemorrhage. Cerebral hemorrhage, a previously reported complication of sildenafil, developed in an infant after a rapid increase in dose, to 4.7 mg/kg/day. Therefore, sildenafil doses must be increased only with care, and cerebral hemorrhage must be considered a potential complication.
Pediatric Cardiology 08/2009; 30(7):998-9. · 1.30 Impact Factor
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American Journal of Kidney Diseases 08/2009; 54(4):764-9. · 5.43 Impact Factor
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ABSTRACT: Standard treatment of acute Kawasaki disease involves giving 2 grams per kilogram of immunoglobulin intravenously along with aspirin. More than half of the patients with acute Kawasaki disease, nonetheless, can be cured by giving only 1 gram per kilogram of immunoglobulin, thus reducing this aspect of the cost of treatment by half. Our purpose was to predict those patients with acute Kawasaki disease who would respond to treatment with 1 gram per kilogram of immunoglobulin given intravenously on the basis of their clinical profiles and laboratory findings prior to the initial treatment. We performed a retrospective review of the clinical records of consecutive patients with acute Kawasaki disease treated in our hospital with intravenous immunoglobulin from January, 2001, to December, 2005.During this period, we treated in this fashion 98 patients with acute Kawasaki disease. 65% of these needing immunoglobulin therapy were cured by giving 1 gram per kilogram. The neutrophil count and the percentage of white blood cells representing neutrophils, along with aspirate aminotransferase, alanine aminotransferase, bilirubin and C reactive protein, were all significantly lower, and sodium was significantly higher, in those responding to 1 gram per kilogram of immunoglobulin when compared to those who did not respond. The days of illness at the first intravenous treatment was later in those responding than in those failing to respond. We generated a score for prediction, assigning a point for each of C reactive protein equal to or greater than 10 mg/dl, sodium equal to or lower than 133 meq/l, alanine aminotransferase equal to or greater than 110 IU/l, and 2 points for the percentage of white blood cells representing neutrophils equal to or greater than 70%. Using a cut-off point of a score less than 2, we were able to identify those responding with 60% sensitivity, and 91% specificity.Thus, we are now able to predict those patients with acute Kawasaki disease who will respond to immunoglobulin given intravenously at 1 gram per kilogram using laboratory data, with a potential saving in medical costs.
Cardiology in the Young 04/2009; 19(3):224-7. · 0.76 Impact Factor
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ABSTRACT: Neonatal toxic shock syndrome (TSS)-like exanthematous disease (NTED) is an emerging neonatal infectious disease caused by TSS toxin-1 (TSST-1). Although NTED and TSS are caused by the same superantigenic exotoxin, NTED is less severe than TSS. The mechanism of this reduced severity in NTED has not been elucidated. Thirteen patients with NTED were enrolled in the study. We investigated serum cytokine profile using a cytometric bead array system with a cytokine panel. Expression of Vbeta2 and CD45RO in CD4(+) T cells was investigated in mononuclear cells by using flowcytometry. Ten patients with other bacterial infections and eight patients without any infections were also enrolled as control groups. The mean serum level of IL-10 was 1209.9 pg/mL in patients with NTED at the time of admission into the study. The other inhibitory cytokine, IL-4, exhibited a minimum level. The high level of IL-10 rapidly decreased within 3-9 days of the onset of NTED. The cytokine profile of NTED, with its high IL-10 level, was clearly different from that of the other bacterial infections. The increased level of IL-10 seems to be related to the reduced severity of NTED. Th2 shift is not thought to be the cause of this IL-10 excretion.
Cytokine 01/2009; 45(1):39-43. · 3.02 Impact Factor
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ABSTRACT: Very low birth weight (VLBW) infants sometimes develop abdominal distension and poor weight gain. The influence of thyroid function on these symptoms in VLBW infants has not been reported.
In a retrospective study, 18 VLBW infants whose abdominal distension and poor weight gain did not improve with standard treatment were enrolled as subjects. Serum levels of free thyroxin (fT(4)) and thyroid stimulating hormone (TSH) were measured. Subjects with serum fT(4) levels less than 1.3 ng/dl received thyroxin supplementation. Another 18 VLBW infants were recruited as age- and weight-matched controls. We compared degree of intestinal dilation on X-ray, weight gain, and quantity of milk tolerated before and after starting thyroxin supplementation in the subjects and the controls.
All subjects had serum fT(4) levels less than 1.3 ng/dl (mean, 0.72 ng/dl). TSH values varied widely and were less than 8 microU/ml in 12 subjects. Therefore, all subjects received thyroxin supplementation; after starting this, mean serum fT(4) level increased significantly to 1.31 ng/dl. In parallel with fT(4) increase, intestinal dilation improved in 16 of 18 subjects (mean grade of dilation decreased from 2.8 to 1.6). Weight gain and quantity of tolerated milk were significantly increased with thyroxin supplementation in all and 17 of the 18 subjects, respectively.
Thyroxin supplementation was effective in improving abdominal symptoms in VLBW infants whose serum fT(4) level was less than 1.3 ng/dl.
Early human development 01/2009; 85(4):267-70. · 2.12 Impact Factor
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ABSTRACT: We measured integrated backscatter (IBS) in the brain of preterm infants using acoustic ultrasound. The study group consisted of 25 preterm infants (gestational age, 32.4+/-2.5 weeks; birth weight, 1488+/-422 g). In parasagittal scans through the posterior horn of the lateral ventricle, regions of interest (ROI) were positioned in the cerebral white matter near the posterior horn (P), anterior horn (A) of the lateral ventricle, and the thalamus (T). IBS of the ROI was measured and IBS of P minus T (P-T) and IBS of A minus T (A-T) were calculated. A-T was greater than P-T. A-T and P-T decreased with increasing gestational age and birth weight. These changes may represent maturation of the cerebrum. A-T or P-T may be useful parameters of cerebral tissue characterization.
Journal of Perinatal Medicine 02/2008; 36(3):253-5. · 1.70 Impact Factor
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ABSTRACT: Medical practice after adolescence in child neurology was discussed. Major issues to be solved included; who should play major role in the practice, what medical facilities are available for inpatients, how medical networks are built in the community (especially for disabled patients), and which medical benefits were required to support patients after the cessation of support for childhood disorders. As child neurologists, we must decide whether we need training in adult neurology as an elective course or compulsory. All these considerations have to be solved by child neurologists for the benefit of maturing patients.
No to hattatsu. Brain and development 06/2005; 37(3):205-7.
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ABSTRACT: The purpose of this study was to assess cardiac function of newborns with mild asphyxia by a Doppler-derived index combining systolic and diastolic performance (Tei index). We studied 20 preterm infants with mild asphyxia. A control group consisted of 20 gestational age-matched preterm infants without asphyxia. Echocardiograms were performed during the fourth and seventh days after birth. Peak velocities of an early filling wave (E) and an atrial contraction wave (A) were measured from the mitral inflow velocity profile and the ratio of peak E to A was calculated. Ejection time was measured from the left ventricular outflow Doppler signal. The sum of isovolumetric times was obtained by subtracting the ejection time from the interval between cessation and onset of mitral inflow. The index was the sum of isovolumetric times divided by ejection time. Ejection fraction was also calculated. The ratio of peak E to A and ejection fraction were the same in both groups. The myocardial performance index in patients with asphyxia was higher than that in patients without asphyxia. We concluded that patients with mild asphyxia have a mild cardiac dysfunction and this change can be detected by a myocardial performance index.
Journal of Perinatal Medicine 02/2005; 33(6):549-52. · 1.70 Impact Factor
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ABSTRACT: We assessed ventricular volume with three-dimensional ultrasonography. The study group consisted of 54 infants admitted to the neonatal intensive care unit (NICU). Gestational age was 32.9+/-3.5 weeks and birth weight was 1774+/-623 g. To obtain images, the transducer was placed on the anterior fontanel. Sagittal sections were serially and automatically scanned from left to right. The angle of scanning was 60 degrees and five seconds were spent on e scanning. Two hundred fifty B-mode images were stored in the built-in computer for later retrieval. We chose the parasagittal sections from the midline to the lateral portion and traced manually an area of the lateral ventricle in each section at intervals of 1 mm. The built-in computer integrated them and measured the ventricular volume. The lateral ventricular size became larger during the first two weeks after birth. The left ventricle was larger than the right one. There was no correlation between lateral ventricular volume and birth weight. Our study shows the normal value of the lateral ventricular volume in neonates.
Journal of Perinatal Medicine 02/2005; 33(4):332-5. · 1.70 Impact Factor
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ABSTRACT: The objective of this study is to determine the difference of the flow velocities of left and right cerebral arteries. We also studied the effect of head position to the cerebral arterial flow velocities. Eligible for inclusion in this study were 60 neonatal infants whose gestational age was 33.1+/-3.5 weeks and whose birth weight was 1793+/-613 g. The ultrasonographic examinations were performed in the first and second weeks after birth. In an axial scan through a temporal window, the Doppler sample volume was positioned at the center of the M1 portion of the middle cerebral artery and the flow velocity curve was detected. No statistical difference was seen in the flow velocities between the left and right middle cerebral arteries. However, the flow velocities in the upper side were significantly higher than those in the lower side. RI in the upper side was significantly smaller than that in the lower one. This change of flow velocities stabilized in 5 min after the head was turned upside down. The effect of head positioning to the intracranial blood flow must be considered when cerebral ultrasonography of neonates is performed.
Early Human Development 11/2002; 69(1-2):35-46. · 2.05 Impact Factor
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ABSTRACT: The objective of this study is to determine the causes of asymmetry of the lateral ventricles in neonates. We also studied the effect of head position and the relationship of body weight at birth in regard to lateral ventricular size. Eligible for inclusion in this study were 60 neonatal infants whose gestational age was 33.1+/-3.5 weeks and whose birth weight was 1793+/-613 g. Ultrasonographic examinations were performed at the first and the second weeks after birth. In parasagittal and coronal scans through the posterior horn of the lateral ventricle, the lateral ventricle was traced and its area was measured. We found no significant variation of ventricular size in relation to body weight at birth. The left ventricular size was larger than the right one. The difference of the left and right ventricular sizes was partially effected by head position. The ratio of left to right lateral ventricular sizes showed a very wide distribution. We considered that ventricular asymmetry is not pathological, but due to individual differences.
Early Human Development 07/2002; 68(1):55-64. · 2.05 Impact Factor
