MRI and MRA of a giant hydrocoele in an infant

We present a 7-month-old boy with a giant abdominoscrotal hydrocoele associated with right leg oedema. US revealed an abdominoscrotal fluid-filled mass with a normal testis in the scrotum. MRI allowed precise delineation of the mass while MRA sequences showed extrinsic compression of the right iliac vein and its patency. Hydrocoelectomy and laparotomy were performed and confirmed the diagnosis. US followed by MRI are often necessary to diagnose and delineate giant hydrocoeles. MRA is a non-invasive elegant tool for the detection of vascular complications.     

窒息宫内窘迫对早期新生儿肾功能的影响

目的：该文通过测定尿α1微球蛋白(α1-MG)、β2微球蛋白(β2-MG)、白蛋白(Alb)含量,探讨窒息、宫内窘迫对早期新生儿肾功能的影响,以期对窒息、宫内窘迫后肾损伤的临床动态监护和防治提供依据。方法：用放射免疫法测定窒息组、宫内窘迫组新生儿生后0~2d,3~4d,6~7d尿α1-MG,β2-MG,Alb含量。结果：窒息组3个时段尿α1-MG,β2-MG,Alb均高于正常对照组,以3~4d最高,差异有显著性(P<0.05)。重度窒息组3个时段尿α1-MG,β2-MG,Alb均高于轻度窒息组,差异有显著性(P<0.05)。尿α1-MG,β2-MG,Alb在宫内窘迫组3个时段之间比较差异无显著性(P>0.05)。宫内窘迫组3个时段尿α1-MG,β2-MG,Alb与正常对照组比较差异无显著性(P>0.05)。结论：窒息可导致新生儿肾小球、肾小管功能损伤,3~4d损伤最严重,损伤程度与窒息程度呈正相关。宫内窘迫新生儿生后1周内肾小球、肾小管功能无明显损伤。     

Programmierung durch intrauterine Mangelversorgung

The concept of perinatal programming comprises the idea that adverse influences during sensitive developmental stages have a long-term impact on the physiology, structure and function of organs. Over the last decades there has been a growing body of evidence, both clinical and experimental that intrauterine deficiency adversely affects intrauterine and postnatal growth trajectories (e.g. catch-up growth) as well as physiological processes in the offspring. This article not only summarizes the causes and the clinical implications of intrauterine growth restriction but also emphasizes the need of translational studies using various animal models to unravel the underlying mechanisms in order to develop strategies for preventing the adverse effects of perinatal programming. Intrauterine deficiency, intrauterine growth restriction (IUGR) and small for gestational age (SGA) have been used interchangeably; however, exposure to reduced nutrient supply does not necessarily result in SGA and IUGR is more a symptom of intrauterine deficiency than the cause of intrauterine programming. The consequences of intrauterine programming are diverse, affecting a multitude of organs notably the kidneys, the lungs and the brain. Clinical and experimental studies have linked intrauterine deficiency and IUGR not only to cardiovascular diseases, such as arterial hypertension and cardiomyopathies and impaired renal function but also to neonatal chronic lung disease and bronchial asthma as well as altered neurocognitive functions in infancy and beyond. Of particular interest is the pathophysiological role of postnatal catch-up growth, which is related to an altered body composition favoring adipose tissue and representing a risk factor for metabolic sequelae. Intrauterine deficiency coupled with postnatal catch-up growth highlights a dual mechanism by which long-term organ structure and function can be programmed: (1) a direct intrauterine-mediated programming effect by nutrient deficiency and (2) an indirect metabolic effect as a result of postnatal catch-up following reduced intrauterine nutrient supply.     

Distribution of adipose tissue in the newborn

Regional differences in adipose tissue distribution are associated with differences in adipocyte metabolism and obesity-related morbidities. Intrauterine growth restriction appears to place individuals at greater risk of obesity associated morbidities in later life. Despite this, little is known regarding the quantity and distribution of adipose tissue in infants during early development. The aim of this study was to compare total and regional adipose tissue content in appropriate-for-gestational-age (AGA) and growth-restricted (GR) newborn infants born at or near term. Whole body adipose tissue magnetic resonance imaging (MRI) was performed as soon as possible after birth. Total and regional adipose tissue depots were quantified. A total of 35 infants (10 GR; 25 AGA) were studied. Mean (SD) total percentage adipose tissue was lower in GR infants than AGA infants [GR: 17.70% (2.17); AGA: 23.40% (3.85); p = 0.003]. This difference arose from differences in subcutaneous adipose tissue mass [mean (SD) percentage subcutaneous adipose tissue mass, GR: 16.13% (2.20); AGA: 21.44% (3.81); p = 0.004], but not intra-abdominal adipose tissue mass [mean (SD) percentage intra-abdominal adipose tissue, GR: 0.42% (0.22); AGA: 0.61% (0.31); p = 0.45]. In contrast to subcutaneous adipose tissue, intra-abdominal adipose tissue is not reduced in infants with intrauterine growth restriction. This suggests that subcutaneous and intra-abdominal adipose tissue compartments may be under different regulatory control during intrauterine life.     

Pilot study of noninvasive detection of venous occlusions from central venous access devices in children treated for acute lymphoblastic leukemia

Background. Survivors of childhood acute lymphocytic leukemia (ALL) are at risk of venous occlusion induced by central venous access devices (CVADs). A sensitive, noninvasive screening technique to identify the magnitude of this problem is needed. Ultrasound (US) cannot always adequately image the innominate veins or the superior vena cava. Magnetic resonance angiography (MRA) can be noninvasive and may be useful for screening these patients. Objective. We examined the suitability of US and MRA to identify venous occlusion. Materials and methods. We used MRA and ultrasound to examine 11 pediatric patients previously treated for ALL. CVADs had been in place a median of 2.5 years (range, 0.4–2.8 years) and removed a median of 2.1 years (range, 0.6–2.9 years) previously. We also performed 2D time-of-flight magnetic resonance angiography (TOF MRA) on two healthy young adult women with no history of venous abnormality or CVAD use. Results. MRA suggested central venous abnormalities in 8 of the 11 ALL survivors and in both healthy control subjects. US results were negative in all 11 survivors. Conclusion. Further investigation is warranted to develop a sensitive and specific noninvasive method for identifying venous occlusion caused by prior CVAD use. Such a method would allow prospective studies of this complication in pediatric ALL survivors. Received: 18 August 1998 Accepted: 23 December 1998     

Occult aneurysmal hemorrhage in a child. Case report and literature review

A unique case of the diagnosis and treatment of a ruptured cerebral aneurysm in a 5-year-old male is presented. The child presented with subarachnoid hemorrhage, and initial CT imaging indicated a right posterior communicating artery aneurysm. Cerebral angiography and MRI/MRA were normal. Repeat cerebral angiogram 3 weeks later was also normal. Sixteen months later, an angiogram was performed to evaluate a subtle carotid bruit found on exam. A carotid bifurcation aneurysm pointing inferior and posterior was found. Craniotomy to clip the aneurysm was performed, and marked adherent gliosis around the lesion was found, supporting the fact that this was the causal lesion of his bleed in the past. Albeit a single case report, it underscores the need for very long-term follow-up and evaluation of idiopathic pediatric subarachnoid hemorrhage.     

Limitations of ultrasonography for diagnosing white matter damage in preterm infants

OBJECTIVES: To compare the accuracy of ultrasonography (US) and magnetic resonance imaging (MRI) in diagnosing white matter abnormalities in preterm infants and to determine the specific indications for MRI. DESIGN: Prospective cohort study. SETTING: A neonatal intensive care unit in France. PATIENTS: All preterm infants (相似文献   

Impact of intrauterine growth restriction on neurodevelopmental and growth outcomes in very low birthweight infants

The impact of intrauterine growth restriction (IUGR) in very low birthweight preterm infants weighing ≤ 1250g was determined by comparing longitudinal growth and neurodevelopmental outcome to an adjusted age of 36 months in 52 intrauterine growth restricted children, with 55 birthweight-matched and 56 gestational age-matched children. None of these children had chromosomal anomalies, congenital infections, or major congenital malformations. Gestational ages of intrauterine growth restricted, birthweight- and gestational age-matched infants were 30 (± 3), 26 (± 2), 29 (± 2) weeks; birthweights were 842 (± 232), 872 (± 201) and 1094 (± 142) g, respectively. Intrauterine growth restricted children had fewer complications during initial hospitalization ( p < 0.05), and had lower weights and head circumferences at follow-up ( p > 0.05). No significant differences were present in major neurodevelopmental disabilities between the intrauterine growth restricted and two comparison groups. Persistence of microcephaly was associated with adverse neurodevelopmental outcome.     

Comparison of MR angiography and conventional angiography in the investigation of intracranial arteriovenous malformations and aneurysms in children

BACKGROUND: Magnetic resonance angiography (MRA) is an attractive alternative to conventional catheter angiography (CCA) in children, especially for the detection of intracranial arteriovenous malformations (AVMs) or aneurysms in the out-of-hours setting, because it has fewer risks and complications. OBJECTIVE. To compare MRA with CCA for the detection of intracranial AVMs, aneurysms and arterial anatomy in children. MATERIALS AND METHODS: Retrospective blinded review of MRAs and CCAs by two independent paediatric radiologists, in a group of 19 children already diagnosed with AVMs, aneurysms and subarachnoid haemorrhage (SAH) and who had undergone both imaging techniques. RESULTS: Abnormalities were identified on MRA in 15 of 19 patients and by CCA in 11 of 19 patients. MRA showed one aneurysm, nine AVMs, three haemorrhages and two indeterminate lesions. CCA showed nine AVMs and two indeterminate lesions. The two modalities showed excellent correlation in the detection of AVMs in nine patients. Vascular supply to the AVMs correlated well in four cases. There was complete disagreement in the determination of vessel supply in one case, and in two cases CCA showed additional vessel supply compared to MRA, while in two further cases MRA showed an additional vessel supply compared to CCA. CCA was superior to MRA in demonstrating arterial anatomy, except with regard to the anterior and posterior communicating arteries where MRA was superior. CONCLUSIONS: The high sensitivity of MRA in the detection of AVMs when compared to CCA and the low incidence of aneurysms support the use of MRA as the initial imaging modality when intracranial haemorrhage is diagnosed on CT, especially in the out-of-hours setting.     

Polyethylene glycol and contrast-enhanced MRI of Crohn's disease in children: preliminary experience

OBJECTIVE: To assess the ability of MRI to detect bowel abnormalities in children affected by Crohn's disease (CD). MATERIALS AND METHODS: We studied 22 children (age range 8-18 years) referred to us with a known history of CD. MRI was carried out using a 1.5-T unit with a maximum gradient field strength of 16 mT and a phased-array body coil. The sequences performed were breath-hold coronal and axial T2-weighted, express fat saturation, followed by T1-weighted, spoiled gradient, fast fat saturation after IV injection of gadolinium chelate (0.3 mmol/kg) for contrast enhancement of the bowel wall. Bowel distension was achieved using oral administration of isosmotic polyethylene glycol solution. Ileo-colonoscopy was considered the gold standard for evaluation of superficial abnormalities and stenoses of the colon and terminal ileum. MRI findings of bowel-wall thickening, increased vascularisation and extramural involvement were compared with the findings using B-mode and Doppler US. Concordance between MRI and endoscopy, B-mode US and Doppler US findings was determined by the Kappa statistical method. RESULTS: Superficial lesions were not shown by MRI. MR enteroclysis easily detected stenoses, thickening and hyperaemia of bowel wall. Concordance of findings between MRI and endoscopy was 90% (K=0.79, substantial concordance). Concordance of findings between MRI and US concerning bowel-wall thickening and increased vascularisation was 95% (K=0.875, excellent concordance) and 80% (K=0.6, fairly good concordance), respectively. CONCLUSIONS: Our initial results show that MRI can detect intra- and extra-mural lesions of CD. The high concordance observed between MRI, endoscopy, US and Doppler US findings suggests that MRI is at least comparable for diagnostic capability with these techniques offering, thanks to multiplanar projections, an improved visualisation of the bowel without ionising radiation.     

Transcranial Doppler, MRA, and MRI as a screening examination for cerebrovascular disease in patients with sickle cell anemia: an 8-year study

Objective. The authors previously reported five transcranial Doppler ultrasonography (TCD) findings as significant in detecting clinical cerebrovascular disease in a 4-year study in patients with sickle cell disease. This is a follow-up to evaluate the validity of the original findings over another 4-year period during which the study population doubled. A clinical follow-up of the original asymptomatic sickle cell patients with positive TCD, MRA, and MRI was also made. Materials and methods. Over an 8-year period TCD, MRI, and MRA were prospectively performed in 90 sickle cell patients who were clinically asymptomatic for stroke and in 27 sickle cell patients with clinical stroke. Results. Of the 4 out of original 46 control patients in 1992 who had positive MRA and TCD, 3 have subsequently had clinical stroke. None of the 9 original patients with positive TCD and positive MRI but negative MRA have developed stroke. All five original TCD indicators of disease were still significant (P < 0.05) for detecting clinical disease: maximum velocity in ophthalmic artery (OA) > 35 cm/s, mean velocity in middle cerebral artery (MCA) > 170 cm/s, resistive index (RI) in OA < 50, velocity in OA greater than in MCA, and velocity in posterior cerebral (PCA), vertebral, or basilar arteries greater than in MCA. Four additional factors were also significant: turbulence, PCA or ACA without MCA, RI < 30, and maximum velocity in MCA > 200 cm/s. Conclusion. Positive MRA with a positive TCD in an asymptomatic patient in long-term follow-up suggests a trend for developing clinical stroke. A 4- to 8-year follow-up of nine patients with positive TCD, positive MRI, but not positive MRA did not show development of clinical stroke. Nine Doppler findings are significant in screening for clinically symptomatic vascular disease in sickle cell patients. It is recommended that children with sickle cell disease be screened for cerebrovascular disease with TCD. If one or two indicators of abnormality are present, MRA is recommended. If the MRA is positive, the patient may be considered for transfusion therapy or other treatment for prevention of stroke. Received: 17 April 1997 Accepted: 7 July 1997     

MR angiography in the evaluation of a renovascular cause of neonatal hypertension

Neonatal hypertension occurs in 2% of all infants and it is caused by renovascular abnormalities in 70% of these infants. The gold standard for diagnosing renovascular disease is conventional renal angiography. However, in neonates the procedure is not commonly used because of its invasive and technically challenging nature. MRI and MR angiography (MRA) are less invasive yet reliable means of detecting renovascular disease in adults. There is minimal literature on the use of MRI/MRA in neonatal hypertension. We report a neonate with hypertension secondary to a renovascular abnormality in which MRI/MRA was helpful in uncovering segmental renal artery stenosis. The infant underwent partial nephrectomy with subsequent resolution of his hypertension. Further studies are needed to validate the use of MRI/MRA in the evaluation of neonatal hypertension.     

Outcome of intrauterine periventricular haemorrhage and leukomalacia

This case study reports five very low birthweight infants with ultrasound evidence of intrauterine insult to the brain. Intrauterine periventricular haemorrhage (PVH) accompanied by ventricular dilatation occurred in two preterm infants both of whom survived and were severely handicapped at follow-up. Three preterm infants had intrauterine periventricular leukomalacia (PVL); one survived and is severely handicapped at one year of age. Our experience and rare case reports in the literature indicate that intrauterine PVH and PVL carry a high risk of death in the neonatal period and severe neurological sequelae in survivors.     

Outcome of intrauterine periventricular haemorrhage and leukomalacia

This case study reports five very low birthweight infants with ultrasound evidence of intrauterine insult to the brain. Intrauterine periventricular haemorrhage (PVH) accompanied by ventricular dilation occurred in two preterm infants both of whom survived and were severely handicapped at follow-up. Three preterm infants had intrauterine periventricular leukomalacia (PVL); one survived and is severely handicapped at one year of age. Our experience and rare case reports in the literature indicate that intrauterine PVH and PVL carry a high risk of death in neonatal period and severe neurological sequelae in survivors.     

Imaging in intersex disorders

BACKGROUND: Evaluation of the gonads and internal genital structures is an essential component for evaluation of patients presenting with ambiguous genitalia. Ultrasonography (US) and magnetic resonance imaging (MRI) are the two preferred modalities. OBJECTIVE: To compare US and MRI in patients with intersex for localization of gonads and internal genitalia. PATIENTS AND METHODS: Ten patients with proven intersex disorders were included in the study. Findings from US and MRI were corroborated by those from surgery/laparoscopy. RESULTS: For evaluation of the gonads, MRI was found to be marginally more sensitive than US. For internal genital structures, both modalities were found to be equally sensitive and specific with no false positive results. CONCLUSION: US still remains the modality of choice for screening patients with intersex disorders. MRI is helpful in cases with equivocal US findings.     

Applications of magnetic resonance imaging and magnetic resonance angiography to evaluate the hepatic vasculature in the pediatric patient

Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) offer several techniques to evaluate the hepatic vasculature. These techniques are briefly reviewed with reference to the pediatric population. Examples of MRI and MRA in the evaluation of the hepatic vasculature in pediatric patients are presented. Received: 4 May 1998 Accepted: 12 October 1998     

宫内生长受限引起成年人代谢综合征的表观遗传机制研究进展

胎儿宫内生长受限是指胎儿出生体质量低于同胎龄平均体质量的第10百分位数。宫内生长受限与成年后代谢综合征的发生密切相关,宫内环境不良引起的表观遗传改变很可能是成年后发生胰岛素抵抗的重要原因。该文从表观遗传修饰及其重点DNA的甲基化,宫内生长受限与DNA甲基化,宫内生长受限致关键启动子的表观遗传标记改变及可能的干预措施介绍...     

Results of parenchymal and angiographic magnetic resonance imaging and neuropsychological testing of children after stroke as neonates

We describe the long-term follow up of infants after neonatal stroke of the middle cerebral artery (MCA). Stroke was diagnosed by CT scan in eight full-term neonates. Three dimensional (volume) magnetic resonance angiography (MRA) is a noninvasive technique that images the arterial vessels without contrast agents. All patients, aged from 1.5 to 8.4 years, were investigated by MRI and MRA and by neuropsychological tests. Cognitive development was investigated by intelligence tests, tests of visual perception, motor and language development. Out of the eight patients, seven had a retarded mental and motor development, and 50% of the children were treated for epilepsy. Seven patients had a spastic hemiparesis. Seven out of eight children showed major cognitive deficits. In all patients, MRI revealed clear parenchymal defects with variable distribution patterns. MRA studies showed abnormalities corresponding to the expected vascular distribution. Children with complications at delivery, with seizures, and an interruption of the main stem of MCA as demonstrated on MRA had the least favourable long-term follow up prognosis with severe cognitive delays.     

Intrauterine growth correlation to postnatal growth — influence of risk factors and complications in pregnancy

In a population of 616 pregnant women with increased risk of intrauterine growth retardation, we examined the relationship of third trimester fetal growth to maternal and pregnancy risk factors, the infants condition at birth, and postnatal growth. Intrauterine growth velocity was calculated from repeated estimations of fetal weight using ultrasound. Postnatal growth up to 3 months was measured in 313 of the infants. Intrauterine growth velocity was directly correlated to birth weight deviation (R = 0.35, P < 0.0001) and inversely correlated to postnatal growth (R = 0.21, P = 0.0001). Heavy smoking throughout pregnancy was the most pronounced factor associated with loss of fetal growth percentiles (P = 0.006), and it was also associated with postnatal catchup (P = 0.01). Infants who needed neonatal care had significantly lower intrauterine growth velocities compared to the rest of the study group; no correlation was found between intrauterine growth velocity and Apgar scores or umbilical pH. It is concluded that growth retardation in the third trimester can be identified by ultrasound fetometry, and is associated with maladaptation at birth and postnatal catchup. However, the correlations were weak suggesting that deviation at birth reflects, only to a limited degree, acceleration or deceleration of growth in the third trimester.     

Diagnosis of cerebrovascular disease in sickle cell anemia by magnetic resonance angiography

The study of blood flow by means of magnetic resonance techniques has led to a noninvasive magnetic resonance angiography (MRA) technique for imaging large cerebral vessels. Ten children with sickle cell hemoglobinopathy and a history of acute neurologic syndromes were studied with combined parenchymal magnetic resonance imaging (MRI) and MRA. Six had abnormal MRI findings and MRA-defined luminal lesions in the vascular distribution of these parenchymal infarctions. The three children with previous intraarterial angiography had MRA abnormalities that corresponded with vascular lesions on conventional angiograms. Four had normal MRI and MRA findings. We conclude that a combination of MRI and MRA provides a noninvasive screening test for large-vessel disease in this population.