Bilateral complete labyrinthine aplasia with bilateral internal carotid artery aplasia, developmental delay, and gaze abnormalities: a presumptive case of a rare HOXA1 mutation syndrome.

The human HOXA1 mutation syndromes commonly present with abnormalities of the inner ear and ICAs. Previous cases describe varying degrees of hypoplasia or aplasia of the affected structures, often with asymmetric involvement. We present imaging findings documenting complete absence of the ICAs bilaterally with bilateral CLA, which, to our knowledge, has not been previously reported.

Improved delineation of ventricular shunt catheters using fast steady-state gradient recalled-echo sequences in a rapid brain MR imaging protocol in nonsedated pediatric patients.

BACKGROUND AND PURPOSE: Rapid brain MR imaging is often substituted for head CT in multiply imaged patients with shunted hydrocephalus. Fast TSE-T2 sequences are commonly used in these protocols. One limitation of TSE-T2 sequences is the decreased catheter delineation compared with CT. The aim of this study was to compare fast TSE-T2 with rapid SS-GRE sequences in the evaluation of intracranial shunt catheter delineation as part of a rapid nonsedated pediatric brain MR imaging protocol. MATERIALS AND METHODS: We evaluated the findings from 179 consecutive patients who underwent routine clinical imaging according to the rapid nonsedated pediatric brain MR imaging protocol. Comparison of the quality of intracranial shunt catheter localization on SS-GRE versus TSE-T2 was performed. RESULTS: Of the total of 179 rapid nonsedated pediatric brain MR images that were reviewed, 62 (35%) had an intracranial shunt catheter. The shunt catheter tip was better localized on the SS-GRE than on the TSE-T2 images in 49/62 (79%) of these patients. Of the remaining 13/62 (21%), the TSE-T2 was either better or equivalent in localizing the shunt catheter tip. CONCLUSIONS: Our study shows that rapid SS-GRE sequences can provide better delineation of standard intracranial shunt catheters than standard rapid MR imaging protocols containing only fast TSE-T2 sequences.

Imaging and intervention in the gastrointestinal tract in children.

Vascular and interventional techniques have become an integral component of modern pediatric healthcare. Minimally invasive procedures of the gastrointestinal tract now comprise a large part of any active pediatric interventional practice. Magnetic resonance cholangiopancreatography offers a reliable, non-invasive means to evaluate patients with possible pancreatic or biliary pathology. This article reviews treatment of esophageal strictures and placement of gastronomy and gastrojejunostomy tubes and discusses new developments. Placement of percutaneous cecostomy tubes is a relatively new procedure that creatively uses the techniques developed for placement of percutaneous gastronomy tubes. This procedure offers significant benefits and lasting positive lifestyle changes for patients suffering from fecal incontinence. Liver biopsy in high-risk patients can be performed safely using measures designed to significantly decrease the risk of post-biopsy hemorrhage, such as track embolization or the transjugular approach.

Non-endoscopic removal of radiologically placed percutaneous primary gastrostomy tubes: a new technique.

PURPOSE: To present a new technique for non-endoscopic removal of radiologically inserted primary percutaneous gastrostomy tubes (PGT) and to assess the utility and safety of this technique in the pediatric population. MATERIALS AND METHODS: Over a 9-year period 172 children (80 F, 92 M) mean age 10 years (range 0.29-24 years) underwent removal of radiologically placed PGTs in the Radiology Department. All procedures were performed with conscious sedation. The procedure time ranged from 20 to 45 min (mean 30 min). The procedures were performed electively at > or = 3 14 months for either gastrostomy button placement (70), balloon gastrostomy and jejunostomy placement (55), or G tube removal at termination of enteral feeding (15). RESULTS: PGT disc retrievals were successful performed in 169 of 173 (98%). No technical failures occurred, but five procedures failed due to PGT disc lodgement in gastric wall (four), and gastrocolic fistula (one). One child had a repeat procedure due to premature removal of the primary PGT necessitating replacement. No deaths occurred. PGT discs retrieval was performed at a mean time interval of 14 months from initial PGT insertion (range 3-40 months). CONCLUSION: Non-endoscopic GT disc removal is a quick and safe procedure. It facilitates easy conversion to a gastrostomy button in the radiology setting and avoids the risk of a retained percutaneous gastrostomy tube remnant and intra/transmural migration of discs.

"Push-pull" gastrostomy: a new technique for percutaneous gastrostomy tube insertion in the neonate and young infant.

OBJECTIVE: To evaluate a newly developed method combining antegrade and retrograde techniques for percutaneous gastrostomy tube (PGT) insertion in the neonate and young infant. MATERIALS AND METHODS: From January 1994 to December 2000, 85 children (47 male, 38 female), mean age 4.5 months (range 0.44-9.13 months) underwent PGT insertion using the "push-pull" technique. With the addition, 57 children had a jejunostomy tube placed as well at or within 24 h of the PGT procedure. The mean weight was 3.74 kg, range 1.5-7.0 kg. The indications for the procedure included failure to thrive in 40 patients (25%), static encephalopathy in 21 (25%), neurological/congenital abnormalities in 12 (14%), aspiration in 7 (8%), and cardiac problems in 5 (6%). RESULTS: Eighty-five PGTs were successfully inserted in 85 children. One procedure was initially unsuccessful due to failed conscious sedation and was completed under general anesthesia. Four of 85 patients initially had attempted antegrade placement that failed, and the procedure was successfully completed using the "push-pull" method. One major complication occurred: a gastrocolic fistula at day 5 post-procedure, which was surgically repaired without sequelae. Tube-related problems included; tube dislodgement (n = 1) and procedure-related stomal infection (n = 3). CONCLUSION: The "push-pull" gastrostomy technique is a safe, effective method of percutaneous gastrostomy tube placement in neonates. It facilitates successful placement of the PGT in patients in whom the classic antegrade method is not possible. It has become the procedure of choice in this group.

MRCP in the evaluation of pancreaticobiliary disease in children.

BACKGROUND: Radiologic assessment of pancreaticobiliary ductal disease (PBDD) in children currently consists of physiologic tests (radionuclide examinations) or invasive anatomic studies (ERCP and PTC). An accurate noninvasive and reproducible examination that can direct the subsequent need for more invasive studies would be helpful in this patient group. OBJECTIVE: To determine the effectiveness of MRCP as a screening tool for PBBD in the pediatric population. MATERIALS AND METHODS: Over the last year, 33 patients ranging from 7 months to 20 years of age were prospectively evaluated with MRCP on a 1.5 T magnet. One patient was examined twice, several months apart. Thirteen patients had liver transplants. Coronal SPGR and heavily T-2W FSE cross-sectional images were obtained. Standard and oblique 2- to 6-cm-thick slab SSFSE (single-shot fast spin echo) acquisition and 3D MIP reconstruction of 2D FSE images were obtained in the planes of the CBD and pancreatic duct. Nine studies were performed with the patient under sedation with chloral hydrate or nembutal and fentanyl with quiet respiration, and the non-sedated patients were assessed with single breath hold or quiet respiration. Three patients received secretin. MRCP results were correlated with ERCP (9), PTC (7), liver biopsy (13), clinical information (6), surgery (3), and autopsy (2). RESULTS: All 34 studies performed were considered diagnostic. Periportal fluid, proximal bowel fluid, and gallbladder distention did not significantly diminish the diagnostic information in any cases. Motion artifact did not cause serious degradation in image quality. MRCP depicted abnormalities including stones, stricture, intraductal tumor, and extrinsic compression, all of which were confirmed at ERCP, PTC ( two unsuccessful in patients with non-dilated ducts by MRCP), surgery, liver biopsy, and autopsy. There were no false-negative examinations. Normal pancreatic studies performed to exclude pancreas divisum were followed without additional clinical or laboratory evidence of pancreatitis. Secretin administration increased the conspicuity of the pancreatic duct in two of three patients. CONCLUSION: MRCP is a fast non-invasive method of evaluating the pancreatic duct and biliary tree in children. A normal MRCP may obviate the need for PTC or ERCP. Abnormalities detected on MRCP can direct the type of intervention.

Intrahepatic chemoembolization in unresectable pediatric liver malignancies.

OBJECTIVE: To determine the effectiveness of a new multidisciplinary approach using neoadjuvant intrahepatic chemoembolization (IHCE) and liver transplant (OLTx) in patients with unresectable hepatic tumors who have failed systemic chemotherapy. MATERIALS AND METHODS: From November 1989 to April 1998, 14 children (2-15 years old) were treated with 50 courses of intra-arterial chemotherapy. Baseline and post-treatment contrast-enhanced CT and alpha-fetoprotein levels were performed. Seven had hepatoblastoma, and 7 had hepatocellular carcinoma (1 fibrolamellar variant). All patients had subselective hepatic angiography and infusion of cisplatin and/or adriamycin (36 courses were followed by gelfoam embolization). The procedure was repeated every 3-4 weeks based on hepatic function and patency of the hepatic artery. RESULTS: Six of 14 children received orthotopic liver transplants (31 courses of IHC). Pretransplant, 3 of 6 showed a significant decrease in alpha-fetoprotein, while only 1 demonstrated a significant further reduction in tumor size). Three of 6 patients are disease free at this time. Three of 6 patients died of metastatic tumor 6, 38, and 58 months, respectively post-transplant. One of 14 is currently undergoing treatment, has demonstrated a positive response, and is awaiting OLTx. Three of 14 withdrew from the program and died. Four of 14 patients developed an increase in tumor size, developed metastatic disease, and were not transplant candidates. Two hepatic arteries thrombosed, and one child had a small sealed-off gastric ulcer as complications of intrahepatic chemoembolization. CONCLUSION: The results of intrahepatic chemoembolization are promising and suggest that some children who do not respond to systemic therapy can be eventually cured by a combination of intrahepatic chemoembolization orthotopic liver transplant. Alpha-fetoprotein and cross-sectional imaging appear to be complementary in evaluating tumor response. IHCE does not appear to convert an anatomically unresectable lesion to a candidate for partial hepatectomy.

A multihospital survey of radiation exposure and image quality in pediatric fluoroscopy.

BACKGROUND: Traditionally, pediatric radiologists have been advocates of fluoroscopy systems that provide diagnostic images at the lowest possible radiation dose to the pediatric patient. Manufacturers of fluoroscopic equipment vary as to their claims of "low radiation" exposures. OBJECTIVES: To obtain comparative data on radiation exposure and image quality from four pediatric hospitals, across variants of fluoroscopic equipment (such as pulsed versus continuous fluoroscopy). MATERIALS AND METHODS: Images were acquired from phantoms that simulated the size of a 3-year-old child. Phantom results, both stationary and rotating dynamic, were evaluated for radiation exposure and for image resolution of high- and low-contrast objects. RESULTS: Radiation exposure from the four fluoro units varied widely; the lowest-dose selectable fluoro mode produced exposures varying between 34 and 590 mrads/min among the four fluoro units, and the highest-dose selectable fluoro mode produced 540-2,230 mrads/min. The lowest radiation exposures were produced by pulsed fluoro units, and the very lowest radiation exposure was produced by a fluoroscope that had been especially optimized for pediatric imaging. There was only a small variation in image quality among the hospitals for visualization of stationary objects. A wide variability was noted for detection of objects on the moving phantom. CONCLUSIONS: The variability in the number of detected objects was considerably smaller than the variability in radiation exposure. Pulsed fluoroscopy provides improved resolution for moving objects. Optimization of one hospital's fluoroscope especially for pediatric imaging produced the best ratio of image quality to radiation exposure.

Imaging of postnatal maturation of the skull base.

The skull begins to form when mesenchyme thickens and condenses around the developing brain. At the skull base, most of this mesenchyme derives from neural crest, and some arises from general head mesenchyme. This article reviews the patterns for maturation of the ossification, sutures, and synchondroses in the occipital, the sphenoid, and the orbitoseptal regions, and reports additional data derived from specific study of CT scans of the skull base in children and young adults.

Hepatic hemangioendothelioma: clinical experience and management strategy.

PURPOSE: This study sought to define management strategies based on clinical experience in treating infantile hepatic hemangioendothelioma. METHODS: A retrospective analysis of patients with hemangioendothelioma presenting to a tertiary liver transplantation center between 1989 and 1997 was performed. RESULTS: Thirteen patients (median age, 14 days) with hemangioendothelioma were identified. Congestive heart failure (P<.03) and abdominal mass (P<.081) were predictive of 5-month mortality rates. Ultrasonography and computerized axial tomography were the diagnostic modalities most commonly used. Treatment strategies consisted of medical management (steroids and alpha-interferon) and interventional modalities (hepatic artery ligation or embolization, resectional surgery, or orthotopic liver transplantation). Patients who underwent resectional surgery, with or without orthotopic liver transplantation, had a lower 5-month mortality rate (P<.02) and a greater 2-year survival rate (P<.003) than did those who underwent hepatic artery ligation or embolization. Early morbidity and mortality tended to be a consequence of the primary lesion, whereas late morbidity and mortality were reflective of the treatment modality used. CONCLUSIONS: In cases of failed medical management, resectional therapy should be used when possible. If partial hepatectomy is not technically achievable, hepatic artery embolization should be used either as definitive therapy or as a temporizing measure until orthotopic liver transplantation is possible.

The role of portosystemic shunting in children in the transplant era.

PURPOSE: Variceal bleeding in children generally presents in the setting of cirrhosis but may also occur in the absence of liver disease and after successful liver transplantation. The authors reviewed their experience with portosystemic shunting in children to better define its efficacy in sclerotherapy failures, as primary therapy, and its role before and after liver transplantation. METHODS: Between 1983 and 1997, 21 children with recurrent variceal bleeding underwent portosystemic shunting at the authors' institution. Patients were divided into two groups: 13 patients in group I presented with intrinsic liver disease (cirrhosis) as a cause for portal hypertension; eight patients in group II with no liver disease had extrahepatic portal venous thrombosis, five of which occured after successful liver transplantation. The mean age was 8.6 years (range, 3 to 18). Shunt procedures were semielective, and were performed successfully in all children without any operative morbidity or mortality. Follow-up ranged from 6 months to 15 years. RESULTS: Shunt procedures included splenorenal (n = 15), splenocaval (n = 1), side-to-side splenorenal (n = 1), inferior mesenteric vein to renal vein (n = 1), mesocaval (n = 1), and transcutaneous intrahepatic portosystemic shunt (TIPS; n = 2). All patients in group II are alive and well with no further bleeding or occlusions. Of the 13 patients in group I, three had bleeding postshunt, and three patients went on to require liver transplantation because of worsening liver disease. One child died of liver failure with encephalopathy 4 years after shunting. There were two shunt occlusions. CONCLUSIONS: Portosystemic shunting is effective therapy in patients with intrinsic liver disease, with salvage amenable by liver transplantation in the treatment failures. It is definitive therapy in patients with extrahepatic venous thrombosis.

Transhepatic insertion of vascular dialysis catheters in children: a safe, life-prolonging procedure.

INTRODUCTION: Central venous catheters (CVC) have been inserted percutaneously since 1989. This technique has been adapted for transhepatic insertion of large-bore catheters in children with occluded central veins. MATERIALS AND METHODS: Three children aged 5, 11, and 12 years required hemodialysis or plasmaphoresis for treatment of life-threatening conditions. All central veins were occluded, thus transhepatic insertion of a large-bore catheter was necessary. All children underwent successful placement using a combination of ultrasound guidance and fluoroscopy. No complications occurred. DISCUSSION: Transhepatic insertion of large-bore catheters can be performed safely in children. Catheter removal should be accompanied by track embolization to prevent exsanguinating hemorrhage. CONCLUSION: Transhepatic insertion of dialysis catheters is a safe alternative in children with occluded central veins.

Percutaneous gastrostomy tube placement in patients with ventriculoperitoneal shunts.

OBJECTIVE: The purpose of this study is to determine the risk of CNS and/or peritoneal infection in children with ventriculoperitoneal shunts in whom a percutaneous gastrostomy tube is placed. MATERIALS AND METHODS: We placed 205 gastrostomy or gastrojejunostomy tubes from January of 1991 to December 1996. Twenty-three patients (10 boys, 13 girls) had ventriculoperitoneal shunts at the time of placement. All shunts were placed at least 1 month prior to placement of the gastrostomy tube. The patients ranged in age from 8 months to 16 years with a mean age of 6 years, 9 months. Patient weight ranged from 2 kg to 60 kg. All 23 children required long-term nutritional support due to severe neurologic impairment. No prophylactic antibiotics were given prior to the procedure. Of the patients, 21/23 had a 14-F Sacks-Vine gastrostomy tube with a fixed terminal retention device inserted, using percutaneous fluoroscopic antegrade technique. Two of the 23 patients had a Ross 14-F Flexi-flo gastrostomy tube which required a retrograde technique due to a small caliber esophagus in these children. RESULTS: All 23 children had technically successful placements of percutaneous gastrostomy (7) or gastrojejunostomy (16) tubes. Of the children, 21/23 (91%) had no complications from the procedure. Two of 23 (9%) patients demonstrated signs of peritonitis after placement of their gastrostomy tubes and subsequently had shunt infections. In both, children CSF culture grew gram-positive cocci. The antegrade technique was used in both children who developed peritonitis. CONCLUSION: Our study indicates children with ventriculoperitoneal shunts who undergo percutaneous gastrostomy are at greater risk for infection and subsequent shunt malfunction. Therefore, we recommend prophylactic antibiotic therapy to cover for skin and oral flora.

Outcome of children with cerebral edema caused by fulminant hepatic failure.

Mortality is high in patients with fulminant hepatic failure (FHF). Neurologic complications of encephalopathy and cerebral edema are major contributors to mortality. Orthotopic liver transplantation has improved survival in these patients. However, the complexity of medical and surgical problems in this patient population, coupled with a severe shortage of organs, requires careful patient selection. The aim of this study was to describe the neurologic outcome of children with FHF who developed radiologically apparent cerebral edema. The hospital and outpatient records and radiologic studies of 20 children with FHF admitted to Children's Hospital of Pittsburgh from 1981-1995 who developed encephalopathy and computed tomographic evidence of cerebral edema were reviewed. Fourteen patients died (70%), three were left with severe neurologic deficits (15%), and three were left with moderate deficits (15%). Survival was correlated with a lesser degree of coma. Histopathologic examination of eight brains demonstrated cerebral edema and widespread ischemic neuronal necrosis in all eight. The presence of radiographic cerebral edema in children with FHF is an objective measure that indicates a very poor prognosis. Termination of care is a reasonable option. Comprehensive monitoring of cerebral function and intracranial pressure is required in children with FHF. Orthotopic liver transplantation should be performed in children with severe and worsening encephalopathy before the development of radiographically apparent cerebral edema.