Variable interpretation of ultrasonograms may contribute to variation in the reported incidence of white matter damage between newborn intensive care units in New Zealand.

BACKGROUND: The incidence of cerebral white matter damage reported to the Australian and New Zealand Neonatal Network (ANZNN) varies between neonatal intensive care units (NICUs). HYPOTHESIS: Differences in the capture, storage, and interpretation of the cerebral ultrasound scans could account for some of this variation. METHODS: A total of 255 infants of birth weight <1500 g and gestation <32 weeks born between 1997 and 2002 and drawn equally from each of the six NICUs in New Zealand were randomly selected from the ANZNN database. Half had early cerebral ultrasound scans previously reported to ANZNN as normal, and half had scans reported as abnormal. The original scans were copied, anonymised, and independently read by a panel of three experts using a standardised method of reviewing and reporting. RESULTS: There was considerable variation between NICUs in methods of image capture, quality, and completeness of the scans. There was only moderate agreement between the reviewers' reports and the original reports to the ANZNN (kappa 0.45-0.51) and between the reviewers (kappa 0.54-0.64). The reviewers reported three to six times more white matter damage than had been reported to the ANZNN. CONCLUSION: Some of the reported variation in white matter damage between NICUs may be due to differences in capture and interpretation of cerebral ultrasound scans.

Does variation in interpretation of ultrasonograms account for the variation in incidence of germinal matrix/intraventricular haemorrhage between newborn intensive care units in New Zealand?

BACKGROUND: The incidence of germinal matrix/intraventricular haemorrhage (GM/IVH) reported to the Australian and New Zealand Neonatal Network (ANZNN) varies between neonatal intensive care units (NICUs). HYPOTHESIS: Differences in the capture, storage, and interpretation of the cerebral ultrasound scans may account for some of this variation. METHODS: A total of 255 infants with birth weight <1500 g and gestation <32 weeks born between 1997 and 2002 were randomly selected from the ANZNN database, 44 from each of the six NICUs in New Zealand. Twenty two infants from each NICU had cerebral ultrasound scans previously reported to ANZNN as normal; another 22 had scans reported as abnormal. The original scans were copied using digital photography and anonymised and independently read by a panel of three experts using a standardised method of reviewing and reporting. RESULTS: There was considerable variation between NICUs in methods of image capture and quality and completeness of the scans. However, there was little variation in the reporting of scans between the reviewers and the reports to ANZNN (weighted kappa 0.75-0.91). Grade 1 GM/IVH was generally over-reported and grade 4 under-reported to the ANZNN. CONCLUSION: For all NICUs, a high level of agreement was found between the reviewers' reports and the reports to the ANZNN. Thus the variation between NICUs in the incidence of GM/IVH reported to the ANZNN is unlikely to be due to differences in capture, storage, and interpretation of the cerebral ultrasound scans. Further investigation is warranted into the reasons for the variation in incidence of GM/IVH between NICUs.

Rationale for grading intracranial hemorrhage in premature infants.

There is a high incidence of hemorrhage in the germinal matrix and ventricular system in premature infants. Existing systems of grading the extent of hemorrhage into germinal matrix and ventricles of premature babies have limitations. It is necessary to consider correlations of structure (neuroanatomy by ultrasound) with function (outcome of patient). It is suggested that a standardized worksheet for evaluation of cranial ultrasound usage in premature infants be adopted. Such a worksheet allows uniformity of data collection and permits a more efficient method for evaluating correlations of structure with function.

Causes of increased renal echogenicity in pediatric patients.

Review of 2,700 abdominal ultrasonic examinations revealed 56 patients whose kidneys showed increased echogenicity. Echogenic kidneys were associated with medical renal disease in 94% of cases (30% glomerular, 48% tubulointerstitial, 16% end-stage) and with no detectable renal disease in 6% (three patients). Patterns of increased echogenicity and renal size were evaluated. Specific patterns occurred in end-stage renal disease and polycystic kidney disease. Other medical renal diseases had overlapping ultrasonographic features. Some generalizations could be made although increased echogenicity was often nonspecific.

Neonatal intracranial hemorrhage and phenobarbital.

We enrolled 280 intubated babies with birth weights of less than 1,751 g in a double-blind randomized prospective clinical trial to evaluate whether phenobarbital influences the likelihood of developing subependymal-intraventricular-intraparenchymal hemorrhage. Phenobarbital was associated with an increased risk of developing any subependymal-intraventricular-intraparenchymal hemorrhage and was not associated with a diminished risk of either severe hemorrhage or germinal matrix hemorrhage. This increased risk was apparent even after we considered the influence of phenobarbital levels, timing of phenobarbital administrations, institutional differences, quality of ultrasound scans, gestational age- and birth weight-specific effects, ascertainment bias, and other possible confounders of phenobarbital administration.

Nonutility of cineurograms in children with congenital heart disease.

Cineurography is often performed after cineangiocardiography to look for occult congenital urinary tract disease. The accuracy of cineurography was investigated in 171 patients by comparing cineurograms with renal sonograms. One hundred fifteen cineurograms (67%) showed both kidneys well enough to allow assessment of renal structure and function and the results were confirmed in 112 by ultrasonography; 3 cineurograms yielded false-positive results. Limited or no information was obtained from cineurograms of 56 patients (33%) because of nonvisualization or poor visualization of 1 or both kidneys. Of the 11 patients (6%) with urinary tract disease, only 3 were correctly assessed by cineurography. Ultrasonography discovered all 11 renal abnormalities and produced only 1 false-positive result. These data indicate that cineurography is a poor screening test and should be abandoned. When uroradiologic screening is necessary for high-risk patients, sonography is recommended.

Renal findings in 40 individuals with Williams syndrome.

We tabulated the frequency of renal abnormalities in 40 Williams syndrome individuals presenting for medical and/or developmental assessment to a multi-disciplinary Williams syndrome program. The average age at time of assessment was 7 2/12 years. Seven individuals (7/40 = 18%) had abnormalities detected, including nephrocalcinosis = 2; marked asymmetry in kidney size = 2; small kidneys = 1; solitary kidney = 1; and pelvic kidney = 1. Renal function was also assessed. Two individuals had evidence of renal dysfunction, one secondary to nephrocalcinosis and the second due to hypercalcemia and interstitial nephritis of unclear pathogenesis. We examined the frequency of renal artery stenosis in 9 individuals who underwent abdominal angiography during cardiac catheterization. We found unilateral or bilateral mild renal artery narrowing in 4 individuals and normal renal arteries in the remaining 5. Persistent hypertension occurred in only 2 individuals and did not correlate with renal artery status. We conclude that intrinsic renal anomalies, as well as problems secondary to hypercalcemia, occur with sufficient frequency to warrant baseline renal screening in all individuals with Williams syndrome.

Pitfalls in pediatric urinary sonography.

Our review of pediatric urinary tract ultrasonograms over a period of two and one-half years resulted in a catalog of pitfalls. Cases included normal scans mistaken for abnormal and vice versa. These erroneous diagnoses stemmed from the inappropriate selection of the primary imaging test, improper timing of the ultrasonogram, errors of commission or omission in performance of the scans, and improper interpretation of the findings. For ease of reference, the pitfalls are grouped under bladder, ureters, and kidney with emphasis on the first two which are common sources of error.

Sonographic appearance of callosal agenesis: correlation with radiologic and pathologic findings.

Sonographic features are described in six infants in whom total or partial agenesis of the corpus callosum was confirmed by either computed tomographic or pathologic examination. The six patients demonstrated a range of abnormalities involving the neuraxis as well as other systems, notably cardiovascular, gastrointestinal, and genitourinary. Chromosomal abnormalities were present in two patients. The sonographic features of callosal agenesis seen in these patients included: lack of characteristic acoustic interfaces to define the corpus callosum on both coronal and sagittal sonograms; increased separation and parallelism of the bodies of the lateral ventricles; loss of the characteristic convexity of the medial border of the anterior horns of the lateral ventricles; variable prominence of the occipital horns of the lateral ventricles; variable degree of superior extension of the third ventricle; alteration or absence of the cavum septi pellucidi; and radial arrangement of cerebral sulci about the prominent third ventricle. Cases of partial agenesis may show the dysplastic features found in complete agenesis. However, only some of the callosal echoes are present. The sonographic features of partial agenesis in one infant had not been described before.

Periventricular cavitations in the first week of life.

Eleven infants were encountered (nine premature, two term) in whom well-defined small periventricular cavitations were found by sonography in the first week of life. The sonographic findings bore remarkable similarity to subependymal pseudocysts in neonates previously described in autopsy specimens. The cavitations, which were identified predominantly along the superolateral aspects of the lateral ventricles, did not evolve in the manner of postnatally acquired periventricular leukomalacia. The location of the cavitations differed from the site of previously reported lesions of posthemorrhagic and postinfectious germinolysis along the medial aspect of the caudothalamic groove. Neurosonologists and neonatologists should be alerted to this finding and encouraged to follow these infants as a separate group to learn whether neurodevelopmental sequelae occur in these children.

Ultrasonography of the genitourinary tract in children.

The author discusses the utility of ultrasound in investigating the genitourinary tract in neonates, infants, and children, and emphasizes the inter-dependence of ultrasonography and uroradiology.

Ultrasonography of the female pelvis in childhood and adolescence.

The age of the patient is crucial in the consideration of differential diagnoses for pelvic disease. This is especially true in the pediatric population. Ultrasonography is the first, and often only, imaging required for female babies, children, and young adults who present with signs and symptoms referable to the pelvis. Usually, children come to attention because of pelvic mass, pelvic pain, ambiguous genitalia, or abnormal sexual development. It should be remembered that congenital anomalies may not become apparent until the onset of puberty. In all cases, good practice requires that adnexal and uterine anatomy and screening views of each kidney are documented on hard copy. Further evaluation, which consists of MR or CT scanning, depends on the results of the ultrasonograms, the clinical examination, and acuity of the problem.

Early chest radiographs in very low birth weight babies receiving corticosteroids for lung disease.

We set out to determine whether chest radiographs obtained in premature infants between 9-16 days of age are predictive for the development of chronic lung disease of the newborn (CLD). This was a prospective cohort study. The study included 40 babies who were enrolled in a randomized trial of corticosteroid therapy for the prevention of CLD. Chest radiographs were obtained for clinical indications between 9-16 and 25-35 days of age. All chest radiographs were assessed by a single pediatric radiologist who was unaware of the treatment allocation and who used a previously published scoring system devised by Weinstein et al. [Pediatr Pulmonol 1994;18:284-289]. The radiographic score at 9-16 days correlated well with the radiographic score at 25-35 days of age (correlation coefficient, 0.69, P < or = 0.001). The scores at 9-16 days were significantly higher in those babies who had CLD at 28 days postnatal age (PNA) (P = 0.03) and at 36 weeks postmenstrual age (PMA) (P = 0.002). Using a receiver-operator characteristic curve, we have determined that for a radiographic score of 3 or greater at 9-16 days, the sensitivity for CLD was 0.64, and specificity was 0.84. We conclude that a chest radiograph taken between 9-16 days may help predict which at-risk preterm infants will develop CLD.

Measurement of the subarachnoid space by ultrasound in preterm infants.

BACKGROUND: Measurements of the subarachnoid space during routine cranial sonography may provide an indirect method of monitoring brain growth in preterm infants. METHODS: The width of the subarachnoid space was measured on coronal views during head sonography. Initial scans (within five days of birth) were compared with follow up scans. RESULTS: A total of 361 scans were performed on 201 preterm infants. The mean width of the subarachnoid space was < 3.5 mm for 95% of initial scans. It was slightly larger in neonates born closer to term, the equivalent of an increase of 0.02 mm/gestational week (95% confidence interval 0 to 0.10 mm) for initial scans. When the scans of all infants, born at 24-36 gestational weeks who were 36 weeks corrected gestational age were compared, the mean (SD) subarachnoid space was 60% larger for follow up scans than for initial scans: 3.2 (1.38) v 1.95 (1.35) mm (p = 0.002) or the equivalent of a mean increase of 0.20 mm/week (95% confidence interval 0.15 to 0.30 mm) for follow up scans. At 36 weeks corrected gestational age, mean head circumference was not different between those having initial or follow up scans (33.0 (2.0) v 32.2 (1.9) cm; p = 0.31). CONCLUSION: The mean subarachnoid space is normally < 3.5 mm in preterm infants. The difference between initial and follow up scans suggests reduced brain growth in extrauterine preterm babies.

An analysis of ultrasound scanning as a guide in determination of "high" or "low" imperforate anus.

The classic upside-down abdominal roentgenogram and the use of pelvic reference points have frequently been inaccurate in assessing the level of the distal pouch in patients with imperforate anus. The ultrasonic study described is different from that previously reported and allows more precise localization of the distal rectal pouch. A review of our experience allows us to make certain definitive statements about this diagnostic modality.

Antenatal ultrasonography in Dunedin: one year's data.

Two thousand and forty-five pregnancies were registered during one calendar year, at the two hospitals in Dunedin. One thousand five hundred and ninety-four liveborn infants and 15 stillborn infants resulted from 1585 pregnancies. Of this group of pregnant women, 74% had one or more ultrasonographic studies (mean number of scans = 1.5). Of the 1609 infants delivered, 0.4% had a major anomaly of the central nervous system, and 0.7% had hydroenphrosis. Four hundred and sixty pregnancies resulted in spontaneous or therapeutic abortion. Ten point nine percent of those women undergoing therapeutic abortion had ultrasonographic studies. It is apparent from this retrospective audit, that antenatal ultrasonography has become almost routine in those women carrying an infant to term. The relative rarity of fetal anomalies is similar to other, larger, series.

Ultrasound of epigastric injuries after blunt trauma.

Blunt trauma to the epigastrum may result in a retroperitoneal hematoma involving the head of the pancreas and descending duodenum. Secondary effects include obstruction of the gastric outlet, obstruction of the biliary tree, and extrinsic compression of the inferior vena cava. Four patients with epigastric trauma were reviewed who had been examined by ultrasound of the abdomen. Ultrasound showed the extent of the retroperitoneal hematoma, its effect on contiguous organs, and was helpful in clinical management.