Implications of early sonographic evaluation of parapneumonic effusions in children with pneumonia.

OBJECTIVE: To devise a clinically relevant grading system for the sonographic evaluation of parapneumonic effusions, and to evaluate length of hospital stay as a function of treatment approach and sonographic grades. METHODS: Chest sonograms of 46 pediatric patients diagnosed with empyemas and admitted to two medical centers in the last 8 years were retrospectively evaluated using a grading system based on the degree of fibrinous organization within the parapneumonic effusions. Hospital charts were reviewed to determine the method of treatment and length of hospital stay. Patients were divided into two treatment groups: nonoperative (n = 26) (antibiotics alone, or combined with thoracentesis, or tube thoracostomy) and operative (n = 20) (open decortication, or video thoracoscopy and pleural debridement). Patients in the nonoperative group were further subdivided into two groups: those who received antibiotics alone (n = 11) and those who received antibiotics plus nonoperative drainage thoracentesis and/or tube thoracostomy (n = 15). Within each treatment group, patients were subdivided into two ultrasound grades: low (no evidence of organization) and high (evidence of organization such as fronds, septations, or loculations). Student's t test was performed to compare the lengths of hospital stay for each of the treatment groups and ultrasound grades. RESULTS: The length of hospitalization was no different for patients with low-grade ultrasounds in the nonoperative (9.8 days) and operative groups (8.0 days). In contrast, length of hospitalization was significantly shorter for patients with high-grade sonograms in the operative group (8.6 days), when compared with the nonoperative group (16.4 days). Length of hospitalization for patients in the nonoperative group with high-grade sonograms was significantly longer (16.4 days) than for those with low-grade ultrasounds (9.8 days). Furthermore, when the nonoperative patients were divided into an antibiotics alone group and a nonoperative drainage group, the patients with low-grade sonograms had no difference in the length of hospitalization (9.0 days vs. 10.4 days), whereas those patients with high-grade sonograms in the nonoperative drainage group had a significantly longer hospitalization (19.9 days) than the antibiotics alone (high-grade) group (11.4 days). CONCLUSIONS: Patients with a low-grade sonogram had similar length of hospitalization if treated with either nonoperative or operative measures. Patients with high-grade sonograms had significantly shorter length of hospitalization when treated with decortication. Our retrospective study suggests that patients with high-grade ultrasound studies treated nonoperatively do not benefit from pleural drainage procedures or chest tube placement. This study demonstrates the usefulness of early sonographic evaluation of parapneumonic effusions. A prospective study evaluating the usefulness of sonographic assessment of severity of disease in the treatment of children with parapneumonic effusions is warranted on the basis of our retrospective data.

Osteomyelitis secondary to trauma or infected contiguous soft tissue.

Nonhematogenous osteomyelitis (NHO) occurred in 24 pediatric patients (ages 8 months to 18 years; median, 14 years; 23 male) admitted from 1980 to 1985. Predisposing factors included compound fracture (12), deep decubiti (4) and foot puncture (3). Infection involved tibia (7), foot bones (6), proximal femur (3) and ulna (2). Patients presented with drainage (64%), pain or tenderness (44%) and fever (32%) lasting for 1 to 180 days (median, 10 days). In 24% both white blood cell count and erythrocyte sedimentation rate were normal. Initial radiographs were nondiagnostic in 42% after compound fractures. Bone cultures were positive in 15 of 18 (83%) patients for: Staphylococcus aureus (9), Staphylococcus epidermidis (2), Pseudomonas aeruginosa (4), Escherichia coli (2), Enterobacter sp. (2), Streptococcus faecalis, Serratia sp., Klebsiella pneumoniae, Achromobacter xylosoxidans, Aeromonas hydrophila and Pseudomonas fluorescens (1 each). Wound cultures failed to predict bone culture results in 12 of 16 patients (75%). NHO recurred in 8 of 19 patients (42%) despite intravenously administered antibiotics for greater than 28 days and debridement in 7 of 8 patients. The indolent nature of NHO complicates diagnosis, especially in patients with recent compound fractures. Only prompt bone culture can confirm the presence of NHO and reliably guide antimicrobial therapy.

Evaluation of renal resistive index, maximum velocity, and mean arterial flow velocity in a hydronephrotic partially obstructed pig model.

RATIONALE AND OBJECTIVES: The authors investigate, in a controlled pig model, the usefulness of Doppler sonographic measurements of resistive index (RI), maximum velocity (Vmax), and mean velocity (Vmean) in diagnostic evaluation of the partially obstructed kidney. METHODS: Seven female pigs underwent surgical partial unilateral renal obstruction at the ureteropelvic junction. Doppler parameters of RI, Vmax, and Vmean were measured preoperatively and postoperatively in obstructed and contralateral nonobstructed kidneys. The General Linear Model multivariate analysis of variance was used for statistical analysis of data. RESULTS: There was no significant difference in the preoperative control values of RI (P = 0.71), Vmax (P = 0.27), and Vmean (P = 0.12). There was a statistically significant decrease in the Vmax and Vmean after postoperative day 5 in the obstructed kidney compared with the contralateral nonobstructed kidney (P = 0.01 and 0.03, respectively). There was no statistically significant difference in RI during the study. CONCLUSIONS: In this study, RI was not a reliable indicator of partial renal obstruction. Measurements of maximal and mean blood flow velocities reached discriminatory significance only after the fifth postobstructive day, proving insensitive in the immediate postobstructive period. Vmax and Vmean demonstrated a decrease in the partially obstructed renal collecting system after 5 days of obstruction and may serve as useful parameters in the evaluation of obstruction after the immediate acute period, when compared with a nonobstructed contralateral system.

Acoustic neuromas in children.

Although unilateral acoustic neuromas in children are rare, they do occur. There is no gender predilection and the clinical symptoms and signs are similar to those seen in adults. They tend to occur in the absence of neurofibromatosis and are usually benign. Our patient is the youngest yet reported with documented unilateral acoustic neuroma; moreover; she is the first child in whom this tumor has been proven to be malignant both by histopathology and subsequent clinical behavior.

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.

Imaging of neonatal gastrointestinal obstruction.

This article discusses the various origins of gastrointestinal obstruction in the newborn infant in a progressive fashion, from the gastric outlet to the colon. The various entities are considered within the paradigm of high or low obstruction, with particular emphasis on the contribution of the radiologist in diagnosis and non-surgical treatment, outlining the role of plain films, sonography, and contrast studies.

Cysts and cystlike lesions of the lung.

This article has reviewed the major pulmonary cystic lesions occurring in infants and children. The chest radiograph will initially reveal either single or multiple well-circumscribed radiopaque or radiolucent areas. In younger patients, radiopaque lesions are best evaluated with sonography, which can define the internal architecture of the mass, its location, and vascular supply. On the other hand, radiolucent lesions, lesions inaccessible to the sonographic beam, and lesions requiring analysis of the pulmonary parenchyma are best assessed with CT. MR is helpful in the preoperative evaluation of sequestration after infancy. Thus within the framework of an age-dependent algorithm, pulmonary cystic lesions can be analyzed effectively and an appropriate diagnosis established.

Correlation of abdominal rSO2 with superior mesenteric artery velocities in preterm infants.

OBJECTIVE: Near-infrared spectroscopy (NIRS) is used to monitor brain and kidney perfusion in at-risk premature and term neonates. Although NIRS holds potential for bedside monitoring of intestinal perfusion, there is insufficient evidence showing correlation with mesenteric blood flow. To determine if an association exists between abdominal regional oxygen saturation (A-rSO2) and mesenteric blood flow, we compared changes in A-rSO2 to changes in blood flow velocity in the superior mesenteric artery (SMA) before and after feedings in very-low birthweight infants. STUDY DESIGN: A-rSO2 was continuously monitored midline below the umbilicus for 3 days in 18 stable 25 to 31 week bolus-fed infants (median BW 1203 g, median age 5 days). We compared change in SMA velocity from immediately before to 10 min and 60 to 120 min after feeding with change in A-rSO2 over the same time. Spearman's rank correlation was used to ascertain if a significant association existed. RESULT: Change in A-rSO2 was significantly associated with change in systolic, diastolic, and mean SMA velocity from fasting to 60 to 120 min after feeding (P=0.016, 0.021, 0.010) and from 10 min after a feed to 60 to 120 min after feeding (P=0.009, 0.035, 0.032). CONCLUSION: In very preterm infants, A-rSO2 reflects blood flow in the SMA and can provide non-invasive continuous monitoring of intestinal perfusion. Further studies are indicated to determine the sensitivity of NIRS to detect early intestinal pathology in this population.

MRI features of three paediatric intra-articular synovial lesions: a comparative study.

AIM: To determine reliable magnetic resonance imaging (MRI) features differentiating three paediatric intra-articular congenital or neoplastic synovial lesions that contain blood products, from post-traumatic or haemorrhagic inflammatory processes. MATERIALS AND METHODS: This was a retrospective review of MRI findings of 22 paediatric intra-articular congenital or neoplastic synovial lesions, including venous malformation (VM) (n=12), pigmented villonodular synovitis (PVNS; n=8), and synovial sarcoma (SS; n=2). These MRI features were compared with 22 paediatric post-traumatic or inflammatory intra-articular processes containing blood products and producing mass effect. The following imaging features were assessed: presence of a discrete mass, extension, extra-articular oedema, susceptibility, joint effusion, and size. Fisher's exact test was used and results were considered statistically significant when p<0.05. RESULTS: The three intra-articular synovial lesions, compared with controls, were more likely to directly invade osseous structures when a discrete mass was present (13/16, 81.3% versus 1/9, 11.1%; p<0.002) and extend into extra-articular soft tissues (13/21, 61.9% versus 2/17, 11.8%; p<0.003), but were less likely to show extra-articular oedema (3/22, 13.6% versus 13/22, 59.1%; p<0.004), a joint effusion (10/22,45.5% versus 19/22, 86.4%, p<0.01), susceptibility within a joint effusion (0/22, 0% versus 11/22, 40.9%; p=0.00), osseous oedema (3/16, 18.8% versus 7/9, 77.8%; p<0.009), and synovial enhancement (8/21, 38.1% versus 14/16, 87.5%; p<0.003). VMs had characteristic tubular vessels with internal fluid-fluid levels (11/12) that extended into bone (10/12) and extracapsular soft tissues (11/12). CONCLUSION: Our study indicates that, despite the overlapping presence of haemorrhagic products, intra-articular VM, PVNS, and SS show MRI features that permit distinction from acquired post-traumatic and haemorrhagic inflammatory lesions.

New applications of conventional and Doppler sonography in pediatrics.

Sonography is assuming an increasingly dynamic role in pediatric diagnosis. The small size of the patient and the use of short-focus, higher frequency transducers, coupled with continuous improvement in sonographic equipment, provide remarkably detailed images. The introduction of Doppler technology has catapulted sonography from the realm of purely anatomic information to that of physiologic and angiographic data. In neurosonography, there has been refinement of the nomenclature, quantification, and prognosis of intracranial hemorrhage and ischemic disorders. Doppler technology has helped us in understanding the vascular dynamics that occur after acute interruption of right internal carotid flow in patients who undergo extracorporeal membrane oxygenation. In abdominal diagnosis, sonography is also playing an increasingly important role in assessing both gastrointestinal and renal conditions. This review outlines some of the important concepts underlying pediatric sonography today and reviews some salient contributions of recent literature.

The elusiveness and importance of bladder diverticula in children.

Diverticula of the bladder are due to congenital areas of weakness in its wall. Their relationship to ureteral reflux makes them important to discover, yet due to their dynamic nature they can be elusive on uroradiologic studies and at cystoscopy. Fluoroscopically monitored voiding cystourethrography is the most efficient method of detection but even this examination has false negatives.

Echogenic vasculature in the basal ganglia of neonates: a sonographic sign of vasculopathy.

The vessels that supply the basal ganglia and thalami are not normally conspicuous on the cranial sonograms of neonates. Twelve neonates with abnormally echogenic or "bright" vessels on cranial sonograms were studied. Records of these 12 patients were reviewed and were correlated with the neuropathologic findings available in four. The clinical diagnoses were cytomegalovirus infection (five patients), rubella (two patients), congenital syphilis (one patient), and trisomy 13 syndrome (three patients). No diagnosis was made in one infant. At neuropathologic examination, perforating medium-sized arteries to the basal ganglia and thalami had thickened hypercellular walls, with deposits of amorphous basophilic material in three infants. Results of computed tomography and radiography of brain sections were normal in these areas. Sonography is helpful in detecting early noncalcific inflammation and mineralization in vasculitis. Although nonspecific, these findings should alert the physician to the possibility of congenital infection or chromosomal abnormality.

Sonography of cerebral infarction in infancy.

Six infants with cerebral infarcts were examined prospectively with real-time sonography to determine the sonographic characteristics of infarcts and their evolution. Patients' ages ranged from 1 day to 7 months, and serial sonographic and/or CT scans were obtained over a period of 2 weeks to 14 months in the survivors. Among our patients the most characteristic sonographic findings of infarction were absence of gyral definition, absence of vascular pulsations, altered parenchymal echogenicity, and territorial distribution. Mass effect, reflected in ventricular size and shift of midline structures, may also be seen and largely parallels the extent of the infarction. Evolution of infarcts was seen sonographically as gradual return of arterial pulsations and concurrent development of cystic spaces. Sonography was found to be a valuable tool in the diagnosis of infarction in infancy and in monitoring its evolution, although CT was necessary for adequate initial evaluation in older infants.

Bilateral duplex ectopic ureters terminating in the seminal vesicles: sonographic and CT diagnosis.

A 15-year-old boy presented with a short history of right-sided flank pain was found to have bilateral duplex renal systems with obstructed upper poles. Sonographic examination and contrast-enhanced delayed computed tomography (CT) performed at the conclusion of the excretory urography (EU) demonstrated termination of both obstructed ureters in the seminal vesicles. These noninvasive studies allowed accurate preoperative diagnosis of this abnormality.

Hemoperitoneum in a newborn secondary to antenatal hemorrhage into a retroperitoneal lymphangioma.

Hemoperitoneum in the newborn is an uncommon event, occurring most often in the setting of traumatic delivery. Hemoperitoneum resulting from antenatal hemorrhage into an abdominal mass is rare. We present a case of neonatal hemoperitoneum secondary to antenatal hemorrhage into a retroperitoneal lymphangioma. The differential diagnosis of neonatal hemoperitoneum is discussed.

Reduced hindbrain herniation after intrauterine myelomeningocele repair: A report of four cases.

BACKGROUND: It has been theorized that fetal myelomeningocele repair may reduce ongoing intrauterine injury and perhaps allow healing and regeneration of dysplastic neural tissue. We report on the postnatal imaging studies of the first 4 patients to have undergone intrauterine myelomeningocele repair at our institution. METHODS: Each of the 4 patients underwent postnatal sonographic and MRI. In addition, the postnatal ultrasounds of these 4 were compared to a group of retrospective controls. RESULTS: MRI scans of the 4 experimental subjects revealed no evidence of hindbrain herniation while other stigmata of the Chiari-II malformation persisted. In comparison to the retrospective controls this absence of herniation was distinctly unusual. CONCLUSION: Intrauterine myelomeningocele repair may reduce the degree of hindbrain herniation normally seen in patients with myelomeningocele. This raises the possibility that intrauterine repair may decrease the morbidity associated with the Chiari type-II malformation including brainstem dysfunction, hydrocephalus and syringomyelia.