Volvulus of the entire small bowel with normal bowel fixation simulating malrotation and midgut volvulus.

BACKGROUND: Midgut volvulus is a complication of malrotation of bowel and mesenteric malfixation. In contrast, primary volvulus of the small bowel is a distinctly different and rare entity characterized by torsion of the entire small bowel with normal mesenteric fixation. OBJECTIVE: To present the clinical and imaging findings in four infants with primary small bowel volvulus and normal bowel fixation in order to improve awareness of this entity among clinicians and radiologists and to discuss the potential etiologies of this entity to distinguish it from other causes of small bowel volvulus. MATERIALS AND METHODS: A retrospective review of imaging studies (two ultrasounds and four upper gastrointestinal series) in four infants (three full-term and one premature) from three institutions with surgically proven volvulus of the entire small bowel and normal bowel fixation were reviewed by three board-certified pediatric radiologists and correlated with clinical and surgical reports when available. RESULTS: The infants presented during the first week to 6 months of life and were acutely ill. The upper gastrointestinal series showed complete duodenal obstruction with beaking in one and partial duodenal obstruction in three. All studies were interpreted as highly suspicious for malrotation and midgut volvulus. Emergent laparotomy demonstrated primary small bowel volvulus with normal mesenteric fixation in all infants. The base of the small bowel mesentery was described by the operating surgeon as smaller than normal in one infant (case 3). There was no mesenteric defect or other abnormality predisposing to volvulus in the other three. In both infants who had abdominal US, a retroperitoneal position of the third portion of the duodenum was demonstrated. All infants survived. One infant required resection of the necrotic small bowel and currently has short gut syndrome, one has malabsorption and two were lost to follow-up. CONCLUSION: Primary small bowel volvulus with normal fixation is indistinguishable from malrotation with midgut volvulus in the acutely ill infant or child. Radiographic diagnosis can be difficult in patients with intermittent or incomplete small bowel volvulus without malrotation. In these patients, neither an upper gastrointestinal series demonstrating a normal position of the duodenojejunal junction nor the sonographic demonstration of a retromesenteric third portion of the duodenum excludes the diagnosis. In young infants, the clinical and imaging findings may mimic necrotizing enterocolitis. Sonography may be useful to evaluate the bowel for signs of bowel wall compromise or a whirlpool sign.

Side-to-side and interpolar renal duplications: the nonpolar variety.

The Weigert-Meyer rule predicts the draining pattern of duplex ureters in bipolar renal duplications. This paper introduces two cases of nonpolar renal duplication. A 3-month-old and a 15-year-old female with history of urinary tract infection were evaluated with intravenous pyelograms (IVP) and eleven different parameters were analyzed. The infant's IVP showed an unobstructed side-to-side right renal duplication with normal-sized nondisplaced lateral moiety and a complete set of calyces, without drooping lily sign. The nonobstructed moiety projected medial and mildly inferior to the lateral moiety which had normal height and axis. The ureters joined each other in lower abdomen. Severe platyspondyly was noted due to hyperalimentation-induced metabolic bone disease. The second case had an unobstructed interpolar extra moiety between the upper and the lower poles with an otherwise unobstructed, normally sized single-system kidney, without drooping lily sign. The paradigm shift from classic anatomic to contemporary cell biological theory validates the nonpolar renal duplication concept, with side-to-side and interpolar arrangements of the moieties, in defiance of Weigert-Meyer rule.

Pericardial tamponade with a normal cardiopericardial silhouette due to a penetrating metallic projectile propelled by a lawnmower.

This report describes a case of pericardial tamponade in a 6-year-old boy due to a penetrating projectile coat hunger wire propelled by a lawnmower. A dismissible dermal injury at the entry point and a normal initial cardiopericardial silhouette are reported. The report issues a new warning to be added to the warnings already listed in lawnmower manuals.

Salt losing obstructive uropathy with paradoxically low urinary sodium concentration: salt entrapment in an obstructed ectopic ureterocele.

A 6-month-old hyponatremic female with failure to thrive had low urinary sodium concentration. Renal sonography revealed a duplex left collecting system with obstruction of the upper moiety as a blind-ended ectopic ureterocele extending to the bladder base. The echogenicity of the urine within the upper pole system was greater than the bladder contents. We believed that low urinary sodium concentration represented a false negative test and the salt loss by the obstructed left kidney was entrapped in the upper pole collecting system. Prior to ureterocele repair, intraoperative bladder and ureterocele aspirates revealed discordant sodium concentration supporting the sonographic conclusion.

Assessment of retromesenteric position of the third portion of the duodenum: an US feasibility study in 33 newborns.

BACKGROUND: US can be used to assess bowel and does not require ionizing radiation or the administration of contrast material. Prior studies of the duodenum with US are limited. OBJECTIVE: This study assesses the success rate of US demonstration of the third portion of the duodenum (D3) between the superior mesenteric artery (SMA) and the aorta in newborns to exclude malrotation based on embryologic and anatomic principles. MATERIAL AND METHODS: Thirty-three newborns underwent US studies. The structures between the SMA and the aorta, including D3, were evaluated in axial and longitudinal planes. The length of time to acquire diagnostic images was recorded. RESULTS: In both the axial and longitudinal planes, D3 was seen between the SMA and the aorta in all 33 infants, including some with abundant bowel gas. The mean length of time to acquire diagnostic images was 34 s. CONCLUSION: Bedside US successfully illustrated the retromesenteric position of D3 in all 33 infants. Overlying gas-filled bowel was effectively effaced by graded compression. The short study duration indicates the practicality of the method. Further studies in broader patient populations and in correlation with other imaging and/or surgical findings is required to validate our technique.

Biphasic threat to femoral head perfusion in abduction: arterial hypoperfusion and venous congestion.

BACKGROUND: Hip abduction can cause avascular necrosis (AVN) of the femoral head in infants. OBJECTIVE: To compare the US perfusion pattern of femoral head cartilage in neutral position with that in different degrees and duration of abduction, testing the venous congestion theory of post-abduction ischemia. MATERIALS AND METHODS: In 20 neonates, the Doppler flow characteristics of the posterosuperior (PS) branch of the femoral head cartilage feeding vessels were evaluated in neutral and at 30 degrees, 45 degrees, and 60 degrees abduction. In three neonates the leg was held in 45-degree abduction and flow was assessed at 5, 10, and 15 min. RESULTS: Male/female ratio was 11/9 with a mean age of 1.86 +/- 0.7 weeks. The peak systolic velocities (PSV) declined in all three degrees of abduction. After 15 min of 45-degree abduction, the mean PSV declined and showed an absent or reversed diastolic component and undetectable venous return. No perfusion was detected at 60-degree abduction. CONCLUSION: Abduction-induced femoral head ischemia is biphasic and degree- and duration-dependent. In phase I there is arterial hypoperfusion and in phase II there is venous congestion. A new pathogeneses for femoral head ischemia is offered.

The position of the duodenojejunal junction: the wrong horse to bet on in diagnosing or excluding malrotation.

PURPOSE: The purpose of this communication is to highlight the shortcomings of all currently used imaging criteria in diagnosing or excluding malrotation and offer ultrasound demonstration of the 3(rd) portion of the duodenum (D3) between the AO and the SMA in transverse and sagittal plains as the most reliable diagnostic method. BACKGROUND: Although UGI is currently considered to be the imaging modality of choice in diagnosis of malrotations, numerous publications indicate that in certain patients, false positives and negatives can be encountered. MATERIALS AND METHODS: The material consists of more than 10 years experience in university settings, during which the author has used US as the definitive imaging modality for the work-up of malrotation. High resolution linear transducers (5-17 MHz) are the transducers of choice. Imaging plains: A. Transverse. With gradual grading compression, the following landmarks are illustrated in cehaplocaudad directions in the following order. The junction of splenic vein with the SMV portal vein. The cross sections of SMA and SMV that may either be situated in midline, or to the right or the left of the midline. Left renal vein crossing the spine from left to right between the AO and the SMA. The jejunal vein, often coming from left, transversing between the AO and the SMA. The transverse portion of the duodenum, D3, between the AO & the SMA. B. Sagittal. D3 between vertically oriented SMA-SMV and the AO. If SMA is not aligned with the AO by slight compression on the right or the left side of the abdomen, it will be aligned (depending on leftward or rightward position of SMA-SMV in axial plain). Vertical orientation of SMA and SMV if they have an anteroposterior orientation. C. Coronal. Side by side orientation of SMA and SMV if they don't have an anteroposterior orientation. RESULTS: In overwhelming majority of cases, by illustrating a retromesenteric D3 malrotation and, therefore, midgut volvulus were excluded. DISCUSSION: None of the current imaging criteria addresses the following most fundamental anatomic and embryologic facts regarding the gut rotation and fixation. In first trimester, the D3 is secured in retroperitoneal space after the embryologic journey comes to an end, making the duodenum immune of midgut volvulus. The surgical pathology of malrotation-midgut volvulus indicates that D3 is always Intraperitoneal and has not reached its final embryologic destination in retroperitoneal space. Demonstrating a retromesenteric D3, therefore, indicates that the embryologic journey is completed and the patient does not have malrotation. Excluding malrotation excludes the likelihood of midgut volvus. CONCLUSION: The position of the DJJ, the configuration of the duodenal sweep, the orientation of the mesenteric vessels are all wrong horses to bet on because none of them addresses the fundamental anatomic and embryologic facts. Only the cross-sectional imaging, US, CT and MRI can prove that the D3 is retromesenteric, therefore, excluding malrotation and volvulus. Therefore, demonstrating a retromesenteric duodenum is the reference standard of imaging in the work-up of malrotation, not any other previously published criteria. The US imaging is the most acceptable imaging method for malrotation work-up, in the spirit of ALARA principle and "Image Gently" campaign.

Internal barium shielding to minimize fetal irradiation in spiral chest CT: a phantom simulation experiment.

PURPOSE: To use a phantom to prospectively examine the attenuating effect of barium sulfate as an internal shield to protect the fetus. MATERIALS AND METHODS: In an adult-size phantom, 1- and 2-cm-thick acrylic slabs containing 315 or 630 mL of water, 2% or 40% barium sulfate suspension, and a 1-mm lead sheet were placed under the diaphragm. In 17 experiments, fetal dose was measured by using thermoluminescent dosimeters that were placed immediately under (near field) and 10 cm below (far field) the water slab (eight experiments), barium sulfate slab (eight experiments), and lead sheet (one experiment). In a pulmonary embolism protocol, the phantom was scanned with single-detector spiral computed tomography (CT) at 130 kVp and 230 mAs. RESULTS: The control radiation dose was 3.60 mSv+/-0.54 (standard deviation) with the water slab at near field, where the uterus dome is at near term, and 0.507 mSv+/-0.07 with the water slab at far field, the uterus position during early gestation. Scattered radiation was attenuated 13% and 21% with 2% barium sulfate and 87% and 96% with 40% barium sulfate, as calculated in the near and far fields, respectively, and 99% with the 1-mm lead sheet. The extrapolated attenuations for 5%-40% barium sulfate suspensions indicated that beyond a 30% suspension, attenuation increased further only slightly. CONCLUSION: Study results in the phantom experiment suggest that fetal irradiation during maternal chest CT can be reduced substantially with barium shielding.

Mesenteric pseudoaneurysm in a 12-year-old girl with abdominal tuberculosis presenting with massive lower gastrointestinal bleeding.

We report a case of a 12-year-old girl with a mesenteric pseudoaneurysm and abdominal tuberculosis presenting with massive lower gastrointestinal hemorrhage requiring multiple blood transfusions. The pseudoaneurysm was treated successfully with transarterial microcoil embolization. Pseudoaneurysms are a rare and life-threatening complication of tuberculosis and understanding the imaging characteristics and treatment options will help to guide appropriate therapy.

Antenatal risk factors associated with the development of lenticulostriate vasculopathy (LSV) in neonates.

OBJECTIVE: To determine the antenatal risk factors associated with neonatal lenticulostriate vasculopathy (LSV). STUDY DESIGN: Women in preterm labor were randomized to magnesium sulfate (MgSO4), other tocolytic, or saline control. The surviving babies underwent head ultrasounds (HUS) (weeks of life 1, 2, and 4) and periodic developmental examinations (months 4, 8, 12, and 18). RESULTS: Of 140 infants, 17.1% (24) had neonatal intraventricular hemorrhage (IVH), and 10.0% (14) had LSV (half of the latter (7 of 14) had both IVH and LSV). In a regression model in which other risk factors were controlled for, the association between antenatal exposures to tocolytic MgSO4 >or=50 g and LSV were significant (adjusted odds ratio (OR), 8.3; 95% confidence interval (CI), 1.5 to 45.0; p=0.01). CONCLUSION: Based on our data and their analyses, we infer that antenatal exposure to high-dosage, tocolytic MgSO4 may be associated with LSV.

Association between lenticulostriate vasculopathy (LSV) and neonatal intraventricular hemorrhage (IVH).

OBJECTIVES: To determine whether there is an unconfounded association between neonatal intraventricular hemorrhage (IVH) and lenticulostriate vasculopathy (LSV (also known as thalamostriate or mineralizing vasculopathy)). STUDY DESIGN: During the conduct of the Magnesium and Neurologic Endpoints Trial (MagNET), a randomized controlled trial involving maternal, hence fetal, exposure to antenatal magnesium sulfate in the context of preterm labor, head ultrasounds were obtained for each of the surviving neonates. Because of our previous experience in the diagnosis of LSV, when ascertaining the presence of IVH, as called for by the research protocol of our study, the presence or absence of LSV was also determined. RESULTS: We found LSV to be relatively prevalent (10% (14 of 140) among surviving babies). More importantly, it was significantly associated with the occurrence of neonatal IVH, even when controlled for possible confounding (adjusted OR 9.8, 95% confidence interval 1.3 to 73.1; p=0.03). CONCLUSION: Given the known relationships between IVH and neonatal morbidity and mortality, the finding of a statistically significant association between neonatal IVH and LSV may suggest more substantial implications for the latter than previously believed.

Association between maternal serum ionized magnesium levels at delivery and neonatal intraventricular hemorrhage.

OBJECTIVES: To determine whether magnesium sulfate (MgSO(4)) exposure is associated with a reduced risk for neonatal intraventricular hemorrhage (IVH). STUDY DESIGN: In a randomized, controlled trial, women in preterm labor were randomly assigned to receive MgSO(4), "other" tocolytic, or saline control. At delivery, we collected maternal antecubital and umbilical cord blood for determination of serum ionized magnesium levels. Neonatal IVH was diagnosed by cranial ultrasonogram. RESULTS: Among 144 infants, 24 were diagnosed with IVH. Using crude intention-to-treat analysis, we found that 18% (13/74) of survivors exposed after birth to MgSO(4) had IVH compared with 16% (11/70) of babies who were not exposed. Infants who had IVH were more likely to have been delivered by mothers with higher serum ionized magnesium (Mg) levels (0.75 vs 0.56 mmol/L) (P =.01). Using multivariable logistic regression, we confirmed that higher Mg levels are a significant predictor of neonatal IVH (adjusted odds ratio, 15.8; 95% CI, 1.4-175.0) even when adjusted for birth weight, gestational age, antenatal hemorrhage, and neonatal glucocorticoid exposure. CONCLUSIONS: In mothers with preterm labor, our data indicate that antenatal MgSO(4) exposure may be associated with an increased risk for IVH among their newborns.