Acute pyelonephritis: comparison of diagnosis with 99mTc-DMSA, SPECT, spiral CT, MR imaging, and power Doppler US in an experimental pig model.

PURPOSE: To compare the sensitivity and specificity of technetium-99m dimercaptosuccinic acid (DMSA) single photon emission computed tomography (SPECT), spiral computed tomography (CT), magnetic resonance (MR) imaging, and power Doppler ultrasonography (US) for the detection and localization of acute pyelonephritis by using histopathologic findings as the standard of reference. MATERIALS AND METHODS: Bilateral vesicoureteric reflux was surgically created in 35 piglets (70 kidneys). One week later, a liquid bacterial culture of Escherichia coli was injected into the bladder. Three days after induction of urinary infection, imaging studies were performed, and the kidneys were removed for histopathologic examination. SPECT images were obtained 2-3 hours after injection of 99mTc-DMSA. Transverse and coronal MR images were obtained with gadolinium-enhanced fast inversion recovery. Transverse CT images were obtained before and after injection of contrast agent. Power Doppler US was performed in longitudinal, transverse, and coronal planes. Each kidney was divided into three zones for correlation of findings. RESULTS: Histopathologic examination revealed pyelonephritis in 102 zones in 38 kidneys. Sensitivity and specificity for detecting pyelonephritis in the kidneys were 92.1% and 93.8% for SPECT, 89.5% and 87.5% for MR imaging, 86.8% and 87.5% for CT, and 74.3% and 56.7% for US. Sensitivity and specificity for detecting pyelonephritis in the zones were 94.1% and 95.4% for SPECT, 91.2% and 92.6% for MR imaging, 88.2% and 93.5% for CT, and 56.6% and 81.4% for US. The pairwise comparison of these modalities showed no statistically significant difference among them except for US. CONCLUSION: 99mTc-DMSA SPECT, spiral CT, and MR imaging appear to be equally sensitive and reliable for the detection of acute pyelonephritis; power Doppler US is significantly less accurate.

Sonographic detection of uterine and ovarian abnormalities in female survivors of Wilms' tumor treated with radiotherapy.

OBJECTIVE: The purpose of this study was to use sonography to evaluate the size of the ovaries and uterus in survivors of Wilms' tumor who underwent radiotherapy. SUBJECTS AND METHODS: Eighteen survivors of Wilms' tumor had their ovaries and uterus measured on sonography. Their ages at diagnosis and treatment ranged from 14 months to 6 years. Four girls were prepubertal (age, 5-9 years), 11 were postpubertal (age, 11-30 years), and three had primary ovarian failure (age, 15-23 years) at the time of imaging. Findings were compared with those of a control group of 25 prepubertal and 25 postpubertal girls and women. Gonadotropin levels were measured. RESULTS: Three patients who underwent whole abdomen radiotherapy had elevated levels of gonadotropin and primary ovarian failure. Neither ovary was seen in two of the three patients and both ovaries were abnormally small (< or = 1 cm3) in the third patient. The uterus was abnormally small (length, < or = 4 cm) in all three of these patients even though two were being treated with hormone replacement therapy. Ten postpubertal patients who underwent hemiabdomen radiotherapy had normal gonadotropin levels and a normal-sized uterus on sonography; the ovary on the side that received radiotherapy was not seen in three of the 10 patients or was abnormally small (< or = 1.4 cm3) in two of the 10 patients compared with all normal ovaries in the postpubertal control group (p < .0001). One postpubertal patient with bilateral renal bed radiotherapy had normal ovaries and a normal-sized uterus. Significantly more patients in the postpubertal and ovarian failure radiotherapy group (5 [36%] of 14 patients) had one or both ovaries not seen than the control group (none [0%] of 25 patients; p = .0014). The uterus was significantly smaller than normal in three (23%) of the 13 patients in the postpubertal hemiabdomen and ovarian failure radiotherapy group versus none of the 25 patients in the postpubertal control group (p = .0339). CONCLUSION: Postpubertal female survivors of Wilm's tumor who underwent radiotherapy as children may have one or two small or absent ovaries and a small uterus that can be detected by sonography. The response of the uterus to hormone replacement therapy can also be assessed on sonography.

Amebic osteomyelitis in a child with acquired immunodeficiency syndrome: a case report.

Disseminated Acanthamoeba infection has been described in immunocompromised or debilitated patients. The usual sites of involvement are skin, sinus, and brain. Sporadic reports of Acanthamoeba infection in patients infected with the human immunodeficiency virus are present in recent literature, predominantly in adults, and one case involving an 8-year-old child. We describe a case of amebic osteomyelitis, seen in a 6-year-old child with vertically acquired human immunodeficiency virus and a 6-month history of cutaneous Acanthamoeba infection.

In-line pressures generated in small-bore central venous catheters during power injection of CT contrast media.

PURPOSE: To determine in-line pressures generated in small-bore central venous catheters during power injection of computed tomographic (CT) contrast media. MATERIALS AND METHODS: Five 3.0-7.0-F central venous catheters for pediatric patients were tested at full and half lengths in vitro. In-line pressures were measured during power injection of three contrast media. Rates of injection were increased in steps from 0.1 to 5.0 mL/sec or until a peak pressure of 100 psi (700 kPa) was achieved. The maximum tolerated flow rate was determined with reference to the manufacturer's suggested operating pressure limit for each catheter. RESULTS: At full length, the maximum tolerated flow rates were as follows: 2-3 mL/sec for the large lumen and 1-1.4 mL/sec for the small lumen of the 7.0-F double-lumen catheter; 0.2-0.4 and 0.8-1.2 mL/sec for the 3.0- and 4.0-F peripherally inserted central catheters, respectively; 0.7-1.2 mL/sec for the 6.6-F catheter; and only 0.2 mL/sec for the 4.2-F catheter, which ruptured during testing at higher flow rates. CONCLUSION: Flow rates were documented at which certain small-bore central venous catheters should tolerate power injection of CT contrast media with peak pressures remaining below the manufacturer's recommended operating pressure limits. These data may serve as a guide for clinical use.

Uterine anomalies in Wilms' tumor survivors.

BACKGROUND: The association between Wilms' tumor (WT) and genitourinary (GU) anomalies has long been appreciated; however, associated GU anomalies have been described almost exclusively in males. METHODS: To investigate whether females with WT also have an increased prevalence of GU anomalies, the authors evaluated the uterine anatomy of 24 WT survivors using magnetic resonance imaging and ultrasonography. RESULTS: Two of 24 female survivors (8%) had anomalies. One had a septate uterus, and a limited molecular analysis of her constitutional DNA revealed no mutations or deletions of the tumor suppressor gene WT1. Another survivor with the WAGR syndrome (WT, aniridia, GU anomalies, and retardation), with the characteristic 11p13 deletion including WT1, had a uterine anomaly (hypoplastic vs. unicornuate). CONCLUSIONS: Because uterine malformations are rare in the general population, this finding suggests an association between WT and uterine malformations and also may partially explain the fertility deficit previously demonstrated in adult female WT survivors. Pelvic ultrasonography in adult female WT survivors can alert survivors and clinicians to possible fertility problems that may lead to problem pregnancies and adverse pregnancy outcomes.

Esophageal pseudodiverticulosis: two new cases in children.

Esophageal intramural pseudodiverticulosis (EIPD) is an uncommon entity in which distended esophageal mucous glands form flask-like outpouchings from the esophagus. Its relationship with esophagitis, gastroesophageal reflux, and benign stricture suggests that it is a consequence of inflammation.

Autosomal dominant polycystic kidney disease in infants: asymmetric disease mimicking a unilateral renal mass.

Unilateral radiographic presentation of autosomal dominant polycystic kidney disease is detected only rarely in infants and may suggest the presence of a complex cystic mass. We report such a case and review the literature concerning unilateral presentation of autosomal dominant polycystic kidney disease in infants and children.

Treatment of intracranial abscesses associated with sinusitis in children and adolescents.

We retrospectively reviewed the management of intracranial abscesses associated with sinusitis in 13 children and adolescents by reviewing medical records and computed tomography (CT) scans of a consecutive case series. The mean duration of follow-up was 4.5 years with a range of 1.3 to 8.6 years, and the setting was a major metropolitan children's hospital providing primary as well as tertiary care. All patients received antibiotics (most commonly chloramphenicol, 75 to 100 mg/kg/day, in combination with oxacillin, 150 to 200 mg/kg/day) to which the sinus and intracranial organisms are susceptible. Surgical drainage of loculated infection was done for patients with acute neurologic symptoms or signs and for those patients whose abscesses enlarged during medical therapy. Three patients underwent immediate drainage of intracranial abscesses because of acute neurologic signs and symptoms. Sequential CT scans demonstrated enlargement of the intracranial abscesses in the remaining 10 patients. This apparent failure of medical management could not be explained by duration of symptoms before therapy, size of lesion, choice of antibiotics, or use of steroids. No child was successfully treated with antibiotics alone. Successful management consisted of antibiotic therapy combined with surgical drainage of loculated infection. This approach to therapy is preferred for all children with intracranial abscess associated with sinusitis.

Scoliosis examinations: organ dose and image quality with rare-earth screen-film systems.

We determined the dose to the breast and evaluated the image quality when various high-speed, rare-earth screen-film systems were used in conjunction with breast dose reduction methods in children undergoing scoliosis examinations. In addition, normalized organ dose to the breast, active bone marrow, thyroid, eyes, ovaries, and testes were measured in a pediatric anthropomorphic phantom comparing the anteroposterior and posteroanterior projections. The average measured dose to the breast was 6.9 and 4.0 mrad (10(-5) Gy), respectively, for nominal 400- and 600-speed, rare-earth screen-film systems used in combination with breast dose reduction methods. The image quality of these systems as evaluated by three radiologists was rated as adequate. The dosimetry results with an anthropomorphic phantom showed that the posteroanterior projection provides approximately a threefold reduction in breast dose as compared with the anteroposterior view. However, the dose to the bone marrow is doubled. Rare-earth screen-film systems used in combination with simple dose-reduction methods can provide adequate image quality for scoliosis examination while significantly reducing the radiation dose to the breast.

A comparative evaluation of rare earth screen-film systems. Free-response operating characteristic analysis and anatomic criteria analysis.

Diagnostic accuracy was evaluated in a signal detection experiment that used low-contrast acute lesions in a living dog model. At the high levels of certainty normally used by radiologists, rare earth screen-film systems provided accuracy comparable to that of a reference calcium tungstate screen-film system. Additionally subjective image quality evaluation for a given imaging task (clinical pediatric anterior-posterior chest films) based on visualization of anatomic landmarks and physical parameters has been conducted for several rare earth and one calcium tungstate screen-film system. The correspondence of subjective physical ranking with physical and psychophysical measurements was investigated. Evaluating the visualization of anatomic parameters can provide a clear and objective distinction among systems with comparable physical and psychophysical properties.

Bladder pseudomass following cystography-related bladder trauma.

Transient sonographic abnormalities of the urinary bladder in children can be identified immediately after performance of voiding cystourethrography. Both cystic and solid masses may be mimicked by transient hematuria induced by minor, cystography-related trauma. After the bladder has been emptied and refilled, reexamination shows prompt resolution of these pseudo-masses.

Spontaneous resolution of cholelithiasis in infants.

Follow-up sonographic studies of five infants whose initial sonograms had displayed evidence for the diagnosis of cholelithiasis demonstrated spontaneous resolution of the gallbladder defects. These defects may have been caused by tumefactive sludge with acoustic shadowing. Whether sludge or gallstones are being imaged, in the absence of other clinical or imaging evidence of biliary tract disease, conservative (i.e., nonsurgical) management and serial sonograms are recommended.