Cerebrofacial venous anomalies, sinus pericranii, ocular abnormalities and developmental delay

The clinical implications of venous cerebrovascular maldevelopment remain poorly understood. We report on the association of cerebrofacial venous anomalies (including sinus pericranii), ocular abnormalities and mild developmental delay in two children. In addition, one child had a seizure disorder. Complex cerebrofacial slow-flow vascular anomalies may herald an underlying developmental aberration affecting the cerebrofacial and orbital regions.

Complex spinal-paraspinal fast-flow lesions in CLOVES syndrome: analysis of clinical and imaging findings in 6 patients

CLOVES syndrome is a complex disorder of congenital lipomatous overgrowth, vascular malformations, epidermal nevi, and skeletal/scoliosis/spinal anomalies. We report the occurrence of spinal-paraspinal fast-flow lesions within or adjacent to the truncal overgrowth or a cutaneous birthmark in 6 patients with CLOVES syndrome.

Klippel-Trenaunay syndrome and spinal arteriovenous malformations: an erroneous association

BACKGROUND AND PURPOSE

KTS is a rare limb overgrowth disorder with slow-flow vascular anomalies. This study examines the presumed association between KTS and spinal AVMs.

MATERIALS AND METHODS

We performed a MEDLINE search of articles and reviewed textbooks of spinal diseases to study the association between KTS and spinal AVM. Our goal was to ascertain the basis on which the diagnosis of KTS was established and to evaluate the evidence of its association with spinal AVMs. In addition, the data base of the Vascular Anomalies Center at Children's Hospital Boston was queried for patients with KTS, and the association with spinal AVM was investigated.

RESULTS

Twenty-four published reports on spinal AVMs in 31 patients with KTS were reviewed. None of these references provided solid evidence of the diagnosis of KTS in any patient. Clinical data were either incompatible with the diagnosis of KTS or were inadequate to establish the diagnosis. Alternative possible diagnoses (CLOVES syndrome and CM-AVM) were suggested by the first author for 9 of the patients reported in these articles. The medical records of 208 patients with the diagnosis of KTS were analyzed; not a single patient had clinical or radiologic evidence of a spinal AVM.

CONCLUSIONS

An association between KTS and spinal AVM, as posited in numerous references, is most likely erroneous. The association has neither been reliably proved in the limited published literature nor encountered in a large cohort.

A novel association between RASA1 mutations and spinal arteriovenous anomalies

BACKGROUND AND PURPOSE

CM-AVM is a recently recognized autosomal dominant disorder associated with mutations in RASA1. Arteriovenous lesions have been reported in the brain, limbs, and the face in 18.5% of patients. We report a novel association between RASA1 mutations and spinal arteriovenous anomalies.

MATERIALS AND METHODS

In a collaborative study, 5 index patients (2 females, 3 males) with spinal AVMs or AVFs and cutaneous multifocal capillary lesions were investigated for the RASA1 gene mutation.

RESULTS

All 5 patients were found to have RASA1 mutation (2 de novo, 3 familial), and all had multifocal capillary malformations at birth. Neurologic deficits developed at ages ranging from infancy to early adulthood. All spinal anomalies (2 AVMs at the conus, 1 AVM at the lumbosacral junction, and 1 cervical and 1 cervicothoracic AVF) were complex, extensive, and fast-flow lesions. All patients required treatment based on the clinical and/or radiologic appearance of the lesions.

CONCLUSIONS

To our knowledge, an association of RASA1 mutation and spinal AVM/AVF has not been described. MR imaging screening of patients with characteristic CMs and neurologic symptoms presenting at a young age may be useful in detecting the presence of fast-flow intracranial or intraspinal arteriovenous anomalies before potentially significant neurologic insult has occurred.

Infantile hemangiomas involving the neuraxis: clinical and imaging findings

BACKGROUND AND PURPOSE

The neuroradiology and neurosurgery literature is replete with references to "hemangioma" involving the central nervous system (CNS). However, the number of cases of true infantile hemangiomas in the CNS reported to date is 15. Our purpose was to delineate the definition of infantile hemangiomas, determine their prevalence in the neuraxis, and describe their imaging characteristics and associations in this location.

MATERIALS AND METHODS

We reviewed our Vascular Anomalies Center data base from 1999 through May 2008 to assess the prevalence of intracranial or intraspinal involvement within the total cohort of infantile hemangiomas. Fifteen patients were identified with infantile hemangiomas that involved the neuraxis. Two board-certified neuroradiologists reviewed the available imaging of these 15 patients, and a board-certified pathologist reviewed the available histopathology. Clinical records of all 15 patients were reviewed to identify the type of treatment and the treatment response.

RESULTS

Of the 1454 patients listed with infantile hemangioma, 15 (approximately 1.0%) had involvement of the CNS. Eight patients had intracranial infantile hemangioma, 6 had intraspinal hemangioma, and 1 had both. In most instances, there was continuous extension into the neuraxis from an extracranial or extraspinal lesion. There were no cases of a CNS hemangioma without an accompanying extra-CNS tumor. Two patients had findings consistent with posterior fossa anomalies, cervicofacial hemangioma, arterial anomalies, cardiac defects, ocular abnormalities, and associated sternal or ventral defect. Of note, there were no brain or spinal parenchymal signal-intensity abnormalities, and there was no evidence of parenchymal invasion.

CONCLUSIONS

CNS involvement by infantile hemangiomas is an unusual occurrence, which, when recognized, can help optimize patient management.

Intracranial vascular anomalies in patients with periorbital lymphatic and lymphaticovenous malformations

BACKGROUND AND PURPOSE

The purpose of this study was to determine the nature, incidence, and radiologic appearance of intracranial vascular anomalies that occur in association with periorbital lymphatic malformation (LM) and lymphaticovenous malformation (LVM).

MATERIALS AND METHODS

We retrospectively reviewed clinical records and imaging studies of 33 patients ranging in age from the neonatal period to 39 years (mean age, 5.1 years; median age, 1.0 year) who were evaluated for orbital LM or LVM at our institution between 1953 and 2002. Imaging studies, including CT, MR imaging, and cerebral angiograms, were evaluated by 2 radiologists to determine morphologic features of orbital LM and to identify associated noncontiguous intracranial vascular and parenchymal anomalies, including arteriovenous malformations (AVM), cerebral cavernous malformations (CCM), developmental venous anomalies (DVA), dural arteriovenous malformations (DAVM), and sinus pericranii (SP).

RESULTS

The malformation was left-sided in 70% of patients. Twenty-two patients (70%) had intracranial vascular anomalies: DVA (n = 20; 61%), CCM (n = 2; 6%), DAVM (n = 4; 12%), pial AVM (n = 1; 3%), and SP (n = 1; 3%). Arterial shunts were present in the soft tissues in 2 patients (6%). Three patients had jugular venous anomalies. Three patients (9%) had cerebral hemiatrophy, 2 (6%) had focal cerebral atrophy, and 2 had Chiari I malformation.

CONCLUSIONS

Intracranial vascular anomalies, some of which are potentially symptomatic and require treatment, are present in more than two thirds of patients with periorbital LM. Initial imaging of patients with orbital LM should include the brain as well as the orbit.

Dural arteriovenous malformation in a child with Bannayan-Riley-Ruvalcaba Syndrome

Intracranial arteriovenous malformations (AVM) are a rare feature of Bannayan-Riley-Ruvalcaba syndrome (BRRS). Palencia et al reported a case of intracranial arteriovenous malformation in a child with BRRS in a Spanish journal in 1986. However, the occurrence of dural AVM in a patient with BRRS has not since been addressed in the literature. Advancements in imaging and therapeutic embolization, and the ability now to screen for phosphatase and tensin homologue (PTEN) mutations allow us to detect and manage these patients sooner. Early detection of intracranial AVMs is necessary because of the risk for progression to venous ischemia and resultant neurologic damage. We present the case of a child with headaches and periorbital venous congestion due to a dural AVM with bilateral venous outflow occlusion who was treated with multiple embolizations, now with interval remission of headache symptoms.

Cervicofacial venous malformations. MRI features and interventional strategies

SUMMARY

We retrospectively evaluated 53 consecutive patients with cervicofacial venous malformation who had sclerotherapy. This review included a demographic analysis, MRI reexamination and tabulation of interventional therapeutic strategies. All patients whose MRI studies were included in this review demonstrated characteristic findings: space occupying lesion with hyperintense T2 signal abnormality, patchy contrast enhancement, and no flow signal on the gradient echo images.We concluded that a complete MRI work-up of these patients requires post-contrast scanning and gradient-echo imaging in addition to the standard T1 and T2 weighted spin echo imaging. The majority of patients had sporadic (non-familial) venous anomalies. Sinus pericranii (SP) was identified in six patients (11%) and blue rubber bleb nevus syndrome (BRBNS) was found in two patients (4%). MRI findings of sinus pericranii are discussed in detail. Although sodium tetradecyl and/or absolute ethanol are the most commonly used sclerosants, a wide variety of therapeutic strategies (depending on the nature of the abnormality) are also needed for these patients.

Accuracy of capnography with a 30 foot nasal cannula for monitoring respiratory rate and end-tidal CO2 in children

We tested the accuracy of a low flow (50 cc/min) sidestream capnography system equipped with an experimental 30-foot nasal cannula to monitor ventilatory status in children. End-tidal CO2 and respiratory rate, both at room air and in the presence of supplemental oxygen, were recorded simultaneously from the experimental 30-foot nasal cannula and the standard, FDA approved, 10-foot nasal cannula. The 30-foot nasal cannula was as accurate as the 10-foot nasal cannula in measuring respiratory rate and end-tidal CO2 in children. When supplemental oxygen was delivered by face-mask, there was no dilutional effect on the respiratory rate or end-tidal CO2 recorded with either the 10-foot or 30-foot nasal cannulas in place.

Coagulation abnormalities in pediatric and adult patients after sclerotherapy or embolization of vascular anomalies

OBJECTIVE

The purpose of our study was to examine the coagulation status in patients with vascular anomalies who had undergone sclerotherapy or embolization.

SUBJECTS AND METHODS

Ours was a prospective pilot study of 29 patients who had undergone sclerotherapy or embolization of large vascular anomalies. Fibrinogen, platelet, and d-dimer levels and prothrombin time were obtained before, immediately after, and on the day after the procedure.

RESULTS

Five patients with venous malformations had positive d-dimer levels before the procedure. A subgroup analysis revealed a relationship between the type of agent used and the change in coagulation status. Specifically, a positive relationship was found between the use of dehydrated alcohol or sodium tetradecyl sulfate and a disruption in coagulation profiles as evidenced by a decrease in platelets and fibrinogen, an increase in prothrombin time, and a conversion from negative to positive d-dimers. In contrast, sclerotherapy or embolization with cyanoacrylic, polyvinyl alcohol foam particles, or platinum microcoils was not associated with coagulation disturbances.

CONCLUSION

The coagulation disturbances that occur in response to dehydrated alcohol or sodium tetradecyl sulfate sclerotherapy or embolization could compromise the patient's clotting ability. Patients who receive dehydrated alcohol or sodium tetradecyl sulfate during a preoperative sclerotherapy or embolization may experience coagulation disturbances that could increase the risk of bleeding, thrombosis, or hematoma. This patient population may benefit from the use of glue, foam, or coils as a substitute for dehydrated alcohol or sodium tetradecyl sulfate.

Renal branch artery occlusion in a 13-year-old hypertensive girl: initial treatment and treatment of recurrent stenosis by balloon angioplasty

A 13-year-old girl who recently developed hypertension was diagnosed to have an occluded right renal branch artery and was treated successfully with percutaneous transluminal angioplasty (PTA). To our knowledge, PTA has not been reported as a treatment for totally occluded renal branch arteries, and there is no data available regarding the success rate and possible complications.

Pediatric hepatic vascular anomalies

The typical vascular anomalies (tumors and vascular malformations) that involve the liver in infants and children are summarized. Many of these lesions are complex and require multiple imaging modalities, often including angiography, for precise diagnosis.

Sedatives used in pediatric imaging: comparison of IV pentobarbital with IV pentobarbital with midazolam added

OBJECTIVE

This study was designed to evaluate safety, efficacy, and success of adding IV midazolam to an established IV pentobarbital protocol for pediatric sedation for radiologic imaging. Outcomes included sedation and discharge times as well as adverse events

SUBJECTS AND METHODS

This prospective study compared two different sedation protocols developed by the radiology sedation committee and approved by the hospital sedation committee at our institution. Patients in the pentobarbital group received IV pentobarbital alone, and patients in the pentobarbital--midazolam group received a combination of IV pentobarbital and midazolam. A total of 1070 infants and children were enrolled, and sedation data were entered into a computer database and reviewed at bimonthly radiology sedation committee meetings for safety, efficacy, efficiency, failed sedations, and adverse outcomes.

RESULTS

Mean age distribution, sex, American Society of Anesthesiologists physical status classification, fasting status, weight, and types of examinations were similarly distributed between the two study groups. Analysis of variance indicated longer times were required to sedate and to discharge patients who had received pentobarbital--midazolam (p < 0.001 for both times), even after adjusting for differences in the patients' ages and weights. The pentobarbital--midazolam group required more time to be successfully sedated and more time to discharge from the recovery room. The rates of adverse events and failed sedations were similar for both groups.

CONCLUSION

Midazolam does not have a beneficial effect on pentobarbital sedation and has no effect on the rate of adverse events. The prolonged time needed both to sedate and to discharge (timed from the initial dose of sedation) pediatric patients who have received midazolam should discourage physicians from combining it with pentobarbital for pediatric sedation.

Life-threatening anomalies of the thoracic duct: anatomic delineation dictates management

Congenital anomalies of the thoracic duct are rare, poorly characterized, and difficult to manage. The spectrum of pathophysiologic perturbations, presenting symptoms, radiographic findings, and interventions performed in 4 patients are shown. Accurate anatomic delineation of the malformation was only possible by direct injection contrast lymphangiography. Therapies tailored to address the anatomic aberrations included intralesional sclerotherapy, surgical excision and ligation, lymphovenous anastomosis, and omental interposition to interrupt dysfunctional collateral lymphatics to the lung. Accurate anatomic diagnosis of central lymphatic channel anomalies by contrast lymphangiography facilitates an individualized multidisciplinary approach to repair.

Effects of systematic methyl substitution of metal (III) tris(n-methyl-8-quinolinolato) chelates on material properties for optimum electroluminescence device performance

We relate the chemical structure of a series of methyl (Me) substituted group III metal tris(8-quinolinolato) chelates (nMeq(3)M: n = 0, 3, 4, 5; M = Al(3+), Ga(3+)) to their photoluminescence (PL), electroluminescence, and thermal properties. Methylation of the 8-quinolinol ligand at the 3 or 4 position (pyridyl ring) results in a factor of 1.4 and 3.0 enhancement of PL quantum efficiency (phi(PL)), respectively, whereas methylation at the 5 position (phenoxide ring) results in a factor of approximately 3.0 decrease in phi(PL) relative to the unsubstituted analogue. Electroluminescent quantum efficiencies of undoped organic light-emitting devices using the aluminum tris(8-quinolinolato) chelates are 1, 0.45, 1.4, and 0.80% for unsubstituted 5-, 4-, and 3-methyl-8-quinolinol ligands, respectively. Devices made with the latter two ligands have a higher operating voltage to generate the same current density. Similar trends were observed for methylation of gallium tris(8-quinolinolato) chelates. We relate these results to the thermal properties of the compounds measured by simultaneous differential scanning calorimetry and thermal gravimetric analysis. The C-4 methylated derivatives exhibit approximately 60 degrees C lower crystalline melting points than all other derivatives, indicating the weakest cohesive forces between molecules. Unlike Alq(3), both the C-4 and C-5 methylated derivatives show no recrystallization of the glassy state below 500 degrees C and exhibit approximately 20-25 degrees C higher glass transition temperatures. We infer that methylation of the 8-quinolinol ligand reduces intermolecular interactions and consequently impedes charge transport through the film.

Diffuse venous malformations of the upper limb: morphologic characterization by MRI and venography

OBJECTIVES

To define the morphologic abnormalities in patients presenting with diffuse pure venous malformations (VM) of the upper extremity.

SUBJECTS AND METHODS

A retrospective review of MRI and venography was performed on five patients, aged 6 months to 20 years, with extensive VM of the upper limbs. Abnormalities of major conducting veins were categorized as varicosities, stenoses, and asymmetrical pouches; anomalous venous spaces were classified into confluent lakes, interconnecting channels and spongelike plexiform networks. MRI and venographic data were reviewed separately and then simultaneously in order to establish correlation between types, location, and extent of lesions.

RESULTS

In all patients, the percentage of replacement of normal tissues by VM was shown by MRI to be significantly higher in the distal limb than in the proximal limb. Involvement of multiple tissue layers was seen in all cases, including, with a decreasing rate, muscles, tendons, interosseous membrane of the forearm, and bone. Venography showed superficial varicosities, frequently associated with stenoses and assymetric pouches in all patients. Interconnecting channels and venous lakes were noted in half of the segments, typically in muscle and other deep locations, and subcutaneous spongelike lesions were seen in two patients. MRI provided a more accurate evaluation of tissue extent. Venograms better demonstrated morphological details and provided more information about the venous drainage. Direct comparison of MR images with venograms helped to identify and characterize venous lesions on cross-sectional MR data.

CONCLUSION

Diffuse VM of the upper extremity are most extensive distally, and all tissues layers can be involved, each with a characteristic morphologic appearance. The morphology of different components of the VM is related to the nature of the surrounding tissue.

Noninvoluting congenital hemangioma: a rare cutaneous vascular anomaly

The authors studied a rare, congenital, cutaneous vascular anomaly that grows proportionately with the child and does not regress. A total of 53 patients were compiled from three vascular anomaly centers. These patients' lesions were analyzed for presentation, physical findings, radiologic and histopathologic characteristics, natural history, and outcome after resection. The lesions occurred slightly more often in male patients, always appeared alone, and were located (in order of frequency) in the head/neck region, extremities, and trunk. They were round-to-ovoid in shape, were plaque-like or bossed, occurred in variable shades of pink to purple, and had an average diameter of 5 cm. The overlying skin was frequently punctuated by coarse telangiectasia, often with central or peripheral pallor. The lesions were warm on palpation; fast-flow was further documented by Doppler ultrasonography. Magnetic resonance imaging and angiographic findings were similar to those of common hemangioma of infancy. All lesions were easily excised without recurrence.Histologic examination revealed lobular collections of small, thin-walled vessels with a large, often stellate, central vessel. Interlobular areas contained predominantly dilated, often dysplastic veins; arteries were also increased in number. Small arteries were observed "shunting" directly into lobular vessels or into abnormal extralobular veins. "Hobnailed" endothelial cells lined the small intralobular vessels. Mast cells were increased. Tests for glucose transporter-1, a recently reported reliable marker for common hemangioma of infancy, were negative in all 26 specimens examined. In conclusion, the authors think these clinicopathologic and radiologic features define a rare vascular lesion for which the term "noninvoluting congenital hemangioma" is proposed. These lesions of intrauterine onset may be a variant of common hemangioma of infancy or another hemangiomatous entity with persistent fast-flow.

Highly phosphorescent bis-cyclometalated iridium complexes: synthesis, photophysical characterization, and use in organic light emitting diodes

The synthesis and photophysical study of a family of cyclometalated iridium(III) complexes are reported. The iridium complexes have two cyclometalated (C(**)N) ligands and a single monoanionic, bidentate ancillary ligand (LX), i.e., C(**)N2Ir(LX). The C(**)N ligands can be any of a wide variety of organometallic ligands. The LX ligands used for this study were all beta-diketonates, with the major emphasis placed on acetylacetonate (acac) complexes. The majority of the C(**)N2Ir(acac) complexes phosphoresce with high quantum efficiencies (solution quantum yields, 0.1-0.6), and microsecond lifetimes (e.g., 1-14 micros). The strongly allowed phosphorescence in these complexes is the result of significant spin-orbit coupling of the Ir center. The lowest energy (emissive) excited state in these C(**)N2Ir(acac) complexes is a mixture of (3)MLCT and (3)(pi-pi) states. By choosing the appropriate C(**)N ligand, C(**)N2Ir(acac) complexes can be prepared which emit in any color from green to red. Simple, systematic changes in the C(**)N ligands, which lead to bathochromic shifts of the free ligands, lead to similar bathochromic shifts in the Ir complexes of the same ligands, consistent with "C(**)N2Ir"-centered emission. Three of the C(**)N2Ir(acac) complexes were used as dopants for organic light emitting diodes (OLEDs). The three Ir complexes, i.e., bis(2-phenylpyridinato-N,C2')iridium(acetylacetonate) [ppy2Ir(acac)], bis(2-phenyl benzothiozolato-N,C2')iridium(acetylacetonate) [bt2Ir(acac)], and bis(2-(2'-benzothienyl)pyridinato-N,C3')iridium(acetylacetonate) [btp2Ir(acac)], were doped into the emissive region of multilayer, vapor-deposited OLEDs. The ppy2Ir(acac)-, bt2Ir(acac)-, and btp2Ir(acac)-based OLEDs give green, yellow, and red electroluminescence, respectively, with very similar current-voltage characteristics. The OLEDs give high external quantum efficiencies, ranging from 6 to 12.3%, with the ppy2Ir(acac) giving the highest efficiency (12.3%, 38 lm/W, >50 Cd/A). The btp2Ir(acac)-based device gives saturated red emission with a quantum efficiency of 6.5% and a luminance efficiency of 2.2 lm/W. These C(**)N2Ir(acac)-doped OLEDs show some of the highest efficiencies reported for organic light emitting diodes. The high efficiencies result from efficient trapping and radiative relaxation of the singlet and triplet excitons formed in the electroluminescent process.

Three-dimensional magnetic resonance imaging of fetal brains

We assessed ten prenatal magnetic resonance imaging(MRI) scans for fetal brain anomalies, and identified eight that were suitable for post-processing. Anatomical abnormalities were assessed on three-dimensional (3D) models and compared with two-dimensional (2D) imaging. We calculated the volumes of the intracranial ventricles and of a periventricular haemorrhage. In three cases, additional clinical information was obtained. 3D modelling of the brain in-utero is possible and can be used to plan treatment.

Perioperative considerations in a hypothyroid infant with hepatic haemangioma

Hepatic haemangiomas in infants are rare. An infant with both a hepatic haemangioma and a severe hypothyroid condition, unresponsive to conventional thyroxine therapy, will be described. This case presented here is the perioperative management of a critically ill infant who had myocardial depression secondary to hypothyroidism and a hepatic haemangioma that required embolization. To our knowledge, this is the first published report describing intravenous triiodothyronine as a therapeutic modality to stabilize a hypothyroid infant prior to undergoing a general anaesthetic.

Serum ethanol levels in children and adults after ethanol embolization or sclerotherapy for vascular anomalies

PURPOSE

To evaluate the serum ethanol level in children and adults after ethanol embolization or sclerotherapy for vascular anomalies.

MATERIALS AND METHODS

Serum ethanol level was evaluated in 71 patients with vascular anomalies who underwent ethanol embolization, sclerotherapy, or both. Blood used to determine serum ethanol level was drawn at the end of each procedure.

RESULTS

The relationship between serum ethanol level and amount of ethanol administered was statistically significant. Results of stepwise linear regression analysis showed that the amount of ethanol administered (P <.001) and type of malformation (P =.02) were multivariate predictors of serum ethanol level. Results of logistic regression analysis revealed that the only uni- or multivariate predictor of legal intoxication was the amount of ethanol administered (P =.018). Five patients fulfilled the criteria for legal intoxication, and the mean amount of ethanol administered to these patients was 0.87 mL per kilogram of body weight +/- 0.18 (SD) (range, 0.55-0.99 mL/kg).

CONCLUSION

The volume of ethanol administered is the most reliable predictor of serum ethanol level and legal intoxication. Patients who receive up to 1.0 mL/kg ethanol during embolization or sclerotherapeutic procedures may have elevated serum ethanol levels that could put them at risk of respiratory depression, cardiac arrhythmias, seizures, rhabdomyolysis, and hypoglycemia.

Endorectal pull-through abates gastrointestinal hemorrhage from colorectal venous malformations

BACKGROUND/PURPOSE

Lower intestinal venous malformations are rare anomalies resulting from errors in vascular morphogenesis. These lesions may cause significant chronic and acute gastrointestinal hemorrhage. Venous malformations are unresponsive to angiogenesis inhibitors. Although these anomalies generally are incompletely resectable because of diffuse pelvic and mesenteric involvement, the authors sought to abate bleeding by excluding the lesion from the gastrointestinal lumen.

METHODS

Three patients with circumferential transmural venous malformations of the colorectum, pelvis, and mesentery were identified. Imaging findings were similar among the patients and included circumferential septated bright signal on T2-weighted magnetic resonance imaging (MRI) contrast enhancement, and multiple phleboliths, seen best on computed tomography (CT). The lesion extended from the anus to the splenic flexure in 2 patients and throughout the entire colorectum in the other. Each had daily hematochezia for many years and required transfusions and chronic iron therapy. Although bleeding began in childhood in each patient, no therapy was successful until ages 7, 24, and 45. Colectomy, anorectal mucosectomy (through the pelvic venous malformation), and endorectal pull-through and anastomosis was performed (coloanal in 2 and ileoanal in 1).

RESULTS

Bleeding essentially has been eradicated in all 3 patients with 10- to 57-month follow-up. One patient received a 3-unit transfusion intraoperatively, and the other 2 received none. The most recent patient to undergo surgery, who has residual venous malformation in the remaining 1 cm of anal mucosa, has some mild difficulty with fecal control if her diet results in loose stool.

CONCLUSION

Colectomy with mucosectomy and endorectal pull-through should be considered for diffuse venous malformations of the colorectum before the development of large transfusion requirements.

Micropatterning of organic electronic devices by cold-welding

A simple and general postdeposition electrode patterning technique for active organic electronic devices is demonstrated and is applied to patterning the metal cathodes of organic light-emitting devices. Selective lift-off of the metal cathode layer is achieved by pressing a prepatterned, metal-coated silicon stamp on the unpatterned device layers. Under pressure, the metal coating on the stamp cold-welds to the metal cathode coating the underlying organic films. Subsequent separation of the stamp from the substrate results in removal of the cathode metal in the regions contacted by the stamp, resulting in submicrometer feature definition. A 17x17 passive matrix display, with a pixel size of 440 micrometers by 320 micrometers, was fabricated with this process. Cold-welding followed by lift-off of the cathode metal allows simple, cost-effective, and high-throughput large-area fabrication of organic electronic devices.

The use of oral pentobarbital sodium (Nembutal) versus oral chloral hydrate in infants undergoing CT and MR imaging--a pilot study

BACKGROUND

Chloral hydrate, a commonly used oral sedative for infants undergoing imaging examinations, has a bitter taste and requires relatively large volume, provoking unpleasant reactions from the infants. Experience with an alternative sedative, oral pentobarbital (Nembutal), has not been reported for infants.

OBJECTIVE

To compare patient acceptance of oral Nembutal and oral chloral hydrate for sedation of infants up to 12 months of age.

METHODS AND MATERIALS

Fifty-four infants (mean age: 7 months) were prospectively enrolled. Parents chose Nembutal, chloral hydrate, or no preference. Thirty-eight infants received Nembutal (4-6 mg/kg) mixed with cherry syrup and 16 received chloral hydrate (50-100 mg/ kg). We recorded infant's acceptance of sedative, parental impression of infant's acceptance, time to sedation, time to discharge, adverse effects, parental preference of future sedative.

RESULTS

Infant acceptance and parental impression were better for Nembutal (P < 0.0001). Fewer parents in the Nembutal group preferred another sedative (P = 0.05). There was a trend toward shorter time to discharge with Nembutal (P = 0.03). There were no adverse effects in either group. One infant failed to sedate with Nembutal.

CONCLUSIONS

Compared with chloral hydrate, oral Nembutal has significantly better acceptance by infants and parents, equal effectiveness, and may result in a shorter time to discharge.

Soft-tissue vascular anomalies: utility of US for diagnosis

PURPOSE

To determine the ultrasonographic (US) features that distinguish soft-tissue hemangioma from vascular malformation and one type of malformation from another.

MATERIALS AND METHODS

Eighty-seven vascular anomalies were evaluated by means of US. Lesions were assessed for the presence of solid tissue and abnormal arteries, veins, or cysts. Vessel density, peak flow velocities, and resistive indexes were compared.

RESULTS

There were 49 hemangiomas and 38 vascular malformations. A significantly greater proportion of hemangiomas (48 of 49) compared with vascular malformations (zero of 38) consisted of a solid-tissue mass (P < .001). Vessel density was comparable for hemangioma and arteriovenous malformation (AVM) but significantly greater compared with the other vascular malformations (P < .001 in each case). No differences in mean arterial peak velocity were detected between hemangiomas and malformations. Mean venous peak velocity was significantly higher for AVM than for other vascular malformations and hemangioma. Mean resistive index was greater for lymphatic malformation than for hemangioma or AVM. Abnormal veins, arteries and veins, or cysts were univariate predictors for distinguishing between venous, arteriovenous, and lymphatic malformations (P < .001 in all cases). Solid-tissue mass was the only multivariate predictor for differentiating hemangioma from vascular malformation (likelihood ratio test = 109.8, P < .001).

CONCLUSION

US can be used to distinguish hemangioma from vascular malformation and detect arterial flow. These distinctions are critical for subsequent management and assessing prognosis.

Residual lesions after Kasabach-Merritt phenomenon in 41 patients

BACKGROUND

Kasabach-Merritt phenomenon (KMP) is the association of a vascular tumor and thrombocytopenic coagulopathy. Vascular tumors are either kaposiform hemangioendothelioma or tufted angioma but not "true" common hemangioma of infancy. There is a conspicuous absence in the literature regarding the late outcome and possible residual lesions after apparent clinical cure of KMP.

OBJECTIVE

The purpose of the study was to analyze these residua in a large number of patients.

METHODS

Clinical data on 41 patients who had KMP were accrued in an international cooperative study. The emphasis was on the residual lesions after resolution of the thrombocytopenia and other coagulation abnormalities. Imaging studies (follow-up magnetic resonance imaging studies available for 10 patients) and histologic specimens (30 specimens available for 26 patients, 18 biopsies done during the KMP and 12 concerning the sequelae) were reviewed.

RESULTS

Residual lesions after "cure" of KMP were common. They exhibited 3 clinical patterns: type I lesions (n = 28) showed a cutaneous red stain, with or without associated red papules. The stain might overlap a minor fibrotic infiltration or a significant poorly delineated diffuse fibrotic infiltration. These cutaneous vascular lesions varied in size and appearance over time and were occasionally painful. Type II lesions were telangiectatic streaks and swelling (n = 5), and type III lesions showed a minor, firm, irregular, subcutaneous mass assessed by palpation or deep infiltration evidenced by computed tomography or magnetic resonance imaging (n = 8). A fourth feature was sequelae in muscles and/or joints. Histologically, tufted angioma was more common in the specimens from residual lesions, whereas kaposiform hemangioendothelioma was more common during the active phase of KMP. Imaging findings were remarkably reproducible and revealed a persistent vascular tumor.

CONCLUSION

Residua of tumors associated with KMP are common after the resolution of thrombocytopenia and coagulopathy. They are (more or less) prominent dormant vascular tumors, not "scars" and, clinically as well as histologically, they differ markedly from involuted hemangioma.

Sedation for pediatric radiological procedures: analysis of potential causes of sedation failure and paradoxical reactions

BACKGROUND

Sedation for diagnostic imaging and interventional radiologic procedures in pediatrics has greatly increased over the past decade. With appropriate patient selection and monitoring, serious adverse effects are infrequent, but failure to sedate and paradoxical reactions do occur.

OBJECTIVE

The purpose of this study was to determine, among patients undergoing sedation for radiologic procedures, the incidence of sedation failure and paradoxical reaction to pentobarbital and to identify potentially correctable causes.

MATERIALS AND METHODS

Records of 1665 patients who were sedated in the radiology department from 1 November 1997 to 1 July 1998 were reviewed. Patients failing sedation or experiencing paradoxical reaction were compared with respect to sex, age group, diagnosis, scan type, time of day, NPO status, use of IV contrast and type of sedation agent using the Fisher exact test, Pearson chi-square, analysis of variance (ANOVA), the Student t-test, and logistic regression.

RESULTS

Data analysis revealed a sedation failure rate of 1 % and paradoxical reaction rate of 1.2 %. Stepwise multiple logistic regression revealed that the only significant independent multivariate predictor of failure was the need for the administration of a combination of pentobarbital, fentanyl, and midazolam IV.

CONCLUSION

The low rate of sedation failure and paradoxical reactions to pentobarbital was near optimal and probably cannot be improved with the currently available sedatives.

Vascular malformations of the upper limb: a review of 270 patients

Vascular malformations of the upper limb were once thought to be impossible to properly diagnose and treat. We reviewed our experience with these malformations of the upper limb in 270 patients seen over a 28-year period. These anomalies were slightly more common in females than males (ratio, 1.5:1.0). The malformations were categorized as either slow flow (venous, n = 125; lymphatic, n = 47; capillary, n = 32; combined, n = 33) or fast flow (arterial, n = 33). Three categories of fast-flow malformations were identified and designated as types A, B, and C. Over 90% of these lesions could be properly diagnosed by their appearance and growth pattern within the first 2 years of life. Additional radiographic studies were used to confirm this diagnosis and to define specific characteristics. Magnetic resonance imaging with and without contrast best demonstrated site, size, flow characteristics, and involvement of contiguous structures for all types of malformations. Algorithms for treatment of both slow-flow and fast-flow anomalies are presented. Two hundred sixty surgical resections were performed in 141 patients, including 24 of 33 fast-flow anomalies. Preoperative angiographic assessment, with magnified views, was an important preoperative adjunct before any well-planned resection of fast-flow arteriovenous malformations. The surgical strategy in all groups was to thoroughly extirpate the malformation, with preservation of nerves, tendons, joints, and uninvolved muscle, and microvascular revascularization and skin replacement as required. Resections were always restricted to well-defined regions and often completed in stages. Symptomatic slow-flow malformations and types A and B fast-flow anomalies were resected without major sequelae. Type C arterial anomalies, diffuse, pulsating lesions with distal vascular steal, and involvement of all tissues, including bone, progressed clinically and resulted in amputation in 10 of 14 patients. The complication rate was 22% for slow-flow lesions and 28% for fast-flow lesions.

Sclerotherapy of craniofacial venous malformations: complications and results

Of all vascular anomalies, venous malformations are the most common, and they have a propensity for the head and neck. The authors retrospectively analyzed 40 patients with craniofacial venous malformations who underwent sclerotherapy between October of 1994 and June of 1996 to determine (1) the results of sclerotherapy with ethanol and/or sodium tetradecyl sulfate, (2) the types and rate of complications, and (3) whether outcome correlated with age, sex, location, size, tissues involved, morphology (lobular or varicose), venous outflow, or number of sclerotherapy sessions. The authors also reviewed the results after sclerotherapy and contour resection (n = 18). Comparisons between the results with ethanol and sodium tetradecyl sulfate and between sclerotherapy alone and sclerotherapy and resection combined were not done. The study was composed of three parts. They were (1) a review of records and imaging studies, (2) a panel evaluation of pretreatment and posttreatment photographs, and (3) a questionnaire that determined the patient's (or parent of the patient's) impression of therapy. Interrater and intrarater agreement were analyzed. Sclerotherapy was performed in an angiographic suite, under general anesthesia, using absolute ethanol and/or sodium tetradecyl sulfate. Complications of the treatment included acute blistering (50 percent), hemoglobinuria (28 percent), deep ulceration (13 percent), and nerve injury (7.5 percent). Two patients suffered transient facial paresis, and one had permanent unilateral vocal cord paralysis. Thirty patients (75 percent) were rated as having marked improvement or as being cured by all three members of the panel; 10 patients (25 percent) were rated as having no change or only slight improvement by one or more members of the panel. Interrater reliability was moderately positive, and intrarater reliability was highly positive. Thirty-seven patients or parents of patients (93 percent) responded to the questionnaire. The outcome was considered to be marked improvement or cured in 28 patients (76 percent), and nine respondents (24 percent) described only minor improvement or no change. Logistic regression analysis revealed that only male sex and number of sclerotherapeutic procedures were significant multivariate predictors of outcome. Size, location, tissues involved, morphology, or venous outflow were not determinant. In conclusion, sclerotherapy with ethanol or sodium tetradecyl sulfate is an effective and safe treatment for craniofacial venous malformations. Often, sclerotherapy has to be repeated. For extensive perioral malformations, combined sclerotherapy and resection give the best result.

Helical CT angiography: dynamic cerebrovascular imaging in children

BACKGROUND AND PURPOSE

The purpose of this study was to assess the feasibility of helical CT cerebrovascular imaging (CTCVI) in children and to make initial comparisons with MR angiography and digital subtraction angiography (DSA).

METHODS

Twenty-six patients, ages 3 days to 17 years, were examined with CTCVI. Patients were scanned with 1-mm collimation and 2:1 pitch 30 seconds after the initiation of a hand injection of 2 mL/kg nonionic contrast material (320 mg/dL iodine) with a maximum dose that did not exceed 80 mL (minimum volume, 5 mL in a 2.5-kg infant). Reconstructions were done using maximum intensity projection and integral rendering algorithms. Four patients had CTCVI, MR angiography, and DSA (42 vessels studied) and nine patients had CTCVI and DSA (136 vessels studied). Scores of 1 (not present) to 3 (present in continuity to the first bifurcation) were assigned independently by two radiologists to 32 vessels in each correlated case for each available technique.

RESULTS

There were no technical failures. CTCVI depicted 18 thrombosed dural sinuses, three vascular malformations, one intracranial aneurysm, and four tumors. Ninety-five percent of the vessels seen with DSA were also seen with CTCVI. CTCVI identified all vessels seen on MR angiography.

CONCLUSION

Helical CTCVI is an effective technique for assessing the intracranial circulation in children. In this initial comparison, CTCVI showed more vascular detail than MR angiography, and had fewer technical limitations.

Head and neck vascular anomalies of childhood

Vascular anomalies of the head and neck are common lesions of childhood. The vascular anomalies can be divided into hemangiomas and vascular malformations. Each of these lesions has a characteristic imaging appearance. Correctly classifying the anomaly is essential in directing the treatment of these lesions.

Neurologic complications of cerebral angiography in childhood moyamoya syndrome

Purpose. To determine the incidence of neurologic complications of cerebral angiography in children with moyamoya syndrome (MMS) as compared to children without MMS. Materials and methods. One-hundred-ninety consecutive cerebral angiograms obtained in 152 children were evaluated. Sixty of these angiograms were obtained in 40 children with MMS. Patients underwent neurologic evaluation prior to and after the procedure. For this study, a neurologic complication was defined as any new focal neurologic deficit or alteration in mental status occurring during the procedure or within the ensuing 24 hours. Results. There were 2 neurologic complications within 24 hours of angiography, one in the MMS group and one in the non-MMS group. One patient with MMS became mute following angiography. The symptom resolved within 12 hours. One patient without MMS being examined postoperatively for residual arteriovenous malformation developed intracranial hemorrhage requiring reexploration 12 hours after the angiogram. Using a two-tail Fisher's exact test, there was no significant statistical difference in the ischemic (P = 0.3) or hemorrhagic (P = 1.0) complication rates between the group of patients with MMS and the non-MMS groups. Conclusion. The risk of a neurologic complication from cerebral angiography in children with MMS is low and not statistically different from the risk in children with other cerebrovascular disorders.

MR lymphangiography in infants, children, and young adults

OBJECTIVE

Our objective was to offer a preliminary description of MR lymphangiography; its uses and limitations; and its findings in infants, children, and young adults.

SUBJECTS AND METHODS

Twenty-nine patients underwent 32 MR lymphangiographic examinations for evaluation of vascular malformations, other masses, soft-tissue swelling, gigantism, fluid accumulation, or pain. MR lymphangiography was based on a heavily T2-weighted fast spin-echo sequence and a maximum-intensity-projection algorithm. We assessed the axial and off-axial lymphatic channels in conjunction with MR venography to help differentiate veins from lymphatics. Correlation was made with published lymphangiograms and anatomic diagrams to assist interpretation and (when available) with histologic specimens (n = 11) for validation.

RESULTS

Presumed lymphatic channels were seen universally, although 14 examinations showed incomplete venous signal suppression. Lymphatic channels appeared normal in eight children and in 20 of the 21 asymptomatic contralateral limbs. Ten patients had an increased number and size of off-axial channels, including seven children with large, diffuse low-flow vascular malformations. Enlarged axial and off-axial channels were seen in five patients, four of whom had Klippel-Trénaunay syndrome. Six patients, each with an extensive hemangioendothelioma, Klippel-Trénaunay syndrome, Gorham syndrome, or unilateral body edema, showed absence or interruption of axial channels.

CONCLUSION

MR lymphangiography appears to be a useful noninvasive technique to study superficial and deep lymphatic channels in children with local or diffuse vascular lesions or swelling of extremities. Its limitations notwithstanding, the technique may offer further insight into the nature of vascular anomalies, may direct therapy, and may predict prognosis.

Congenital anomalies and vascular birthmarks of the lower extremities

MR imaging is an invaluable tool for the evaluation of congenital abnormalities and vascular birthmarks of the extremities in children. These abnormalities of the immature musculoskeletal system are often underestimated by radiography. MR imaging is useful for diagnosis, assisting in therapy, showing response to treatment, and determining prognosis. Localized and generalized abnormalities of the lower extremities and issues pertinent to their MR imaging are illustrated in this article.

Gastrointestinal manifestations of vascular anomalies in childhood: varied etiologies require multiple therapeutic modalities

BACKGROUND/PURPOSE

Vascular anomalies, including hemangiomas and vascular malformations afford complex diagnostic and therapeutic challenges when gastrointestinal (GI) manifestations are present.

METHODS

Twenty-one patients evaluated or treated in our Vascular Anomalies Program from 1993 through 1997 were reviewed retrospectively with regard to presentation, treatment modalities, and outcome.

RESULTS

Four patients had hemangiomas, and 17 had various vascular malformations. GI symptoms began in infancy or early childhood in all patients. Manifestations included GI bleeding (n = 15), obstruction (n = 2), diarrhea (n = 2), ascites (n = 2), pain (n = 1), emesis (n = 1), ileo-ileal intussusception (n = 1), protein-losing enteropathy (n = 1), and hypersplenism (n = 1). Four patients had proven portal hypertension. Fourteen had associated musculoskeletal or cutaneous lesions. Congestive heart failure, partial anomalous pulmonary venous return, pulmonary edema, and pleural or pericardial effusion occurred in one patient each. Bleeding was the most common symptom of both hemangiomas and malformations. Of four patients with hemangiomas, three were treated with corticosteroids or interferon. Endoscopic banding and embolization of an associated arterioportal hepatic shunt were each used in one patient. One patient died. The malformations were treated with resection (n = 8), endoscopic banding or sclerosis (n = 7), percutaneous or intraoperative sclerosis (n = 5), embolization or device interruption (n = 3), and portosystemic shunt (n = 2). GI symptoms were ameliorated in 12 patients with malformation, improved in two, unchanged in two, and one died after prolonged palliation.

CONCLUSIONS

Vascular anomalies with gastrointestinal manifestations are heterogeneous in their presentation and type. Although bleeding is the most common symptom of both hemangiomas and vascular malformations, treatment differs. Pharmacological angiogenesis inhibition is the mainstay of hemangioma therapy. Resection, endoscopic or radiologic vascular obliteration, and portal decompression are important in treating vascular malformations. An individualized and interdisciplinary approach is often required to successfully diagnose and treat these complex lesions.

Diagnostic imaging in the evaluation of vascular birthmarks

This article reviews the role of modern diagnostic imaging in the evaluation of patients with vascular birthmarks. There are two main categories of vascular anomalies: hemangiomas and vascular malformations. The findings on plain radiography, sonography, computed tomography (CT), magnetic resonance imaging (MRI) and angiography, and the appropriate sequence of investigation for the different vascular anomalies are discussed.

Cerebral vasculopathy and neurologic sequelae in infants with cervicofacial hemangioma: report of eight patients

PURPOSE

To determine the association of cerebral arterial anomalies and progressive cerebral arterial occlusive disease in infants with facial hemangiomas.

MATERIALS AND METHODS

The cases of eight infants (seven girls and one boy) with the diagnosis of cervicofacial hemangioma and intracranial arterial anomalies were reviewed retrospectively. Findings from clinical and imaging examinations--including cranial computed tomography, magnetic resonance imaging and angiography, and catheter angiography--were evaluated. Serial imaging findings were studied to document progressive intracranial vascular changes.

RESULTS

Five patients had additional associated congenital anomalies. Seven were treated with corticosteroids, interferon alfa-2a, or both. Progressive cerebrovascular occlusive changes were documented in four of the seven patients with serial imaging findings. Four other patients (all treated pharmacologically) had MR imaging documentation of cerebral infarction, and all had consistent, acquired neurologic symptoms.

CONCLUSION

Intracranial arterial anomalies can coexist with cervicofacial hemangioma. Aneurysmal and occlusive changes are potentially progressive and can result in cerebral infarction. A causative association between occlusive cerebrovascular disease and pharmacologic treatment has not been excluded.

Neonatal central nervous system vascular disorders

Central nervous system vascular disorders in the neonate comprise structural anomalies or malformations of arteries and veins and physiologic alterations of cerebral blood flow, which can mimic structural vascular disease. Clinical , imaging, and transcatheter therapeutic aspects of neonatal cerebral vascular malformations are described. Symptomatic high-flow vascular malformations characteristically present with cardiac failure and associated systemic problems in the neonate, whereas infants typically present with macrocephaly and hydrocephalus and older children with hemorrhage, developmental delay, or focal deficits. Neonatal cerebral hemorrhage is typically primary or associated with immaturity, parturitional trauma, or coagulopathy. Likewise, cerebral ischemic lesions are more likely secondary to hypoxic, ischemic events than to thromboembolic or structural cerebrovascular occlusive disease. The role of the current noninvasive imaging modalities in each of these clinical problems is reviewed and illustrated.

Thrombocytopenic coagulopathy (Kasabach-Merritt phenomenon) is associated with Kaposiform hemangioendothelioma and not with common infantile hemangioma

Children with a large vascular tumor and associated Kasabach-Merritt coagulopathy respond inconsistently to therapy and have a high mortality rate. For this reason, we undertook a retrospective study of 21 such patients, and focused on clinical, radiographic, and histopathologic features. The male to female ratio was 1:1.6. Tumor was noted at birth in 50 percent of patients; the remainder appeared throughout infancy. The location was cervicofacial (n = 2), shoulder/upper limb (n = 4), trunk including retroperitoneum (n = 11), and lower limb (n = 4). These tumors grew rapidly to large size and were characterized by cutaneous purpura, edema, and an advancing ecchymotic margin. In contrast to common hemangioma, magnetic resonance imaging showed diffuse enhancement with ill-defined margins, cutaneous thickening, stranding of subcutaneous fat, hemosiderin deposits, and small feeding and draining vessels. All tumors were Kaposiform hemangioendothelioma (KHE); none were infantile hemangioma. Light microscopy showed irregular lobules or sheets of poorly formed, small vascular channels infiltrating and entrapping normal tissues. Characteristic features included spindle-shaped endothelial cells, diminished pericytes and mast cells, microthrombi, and hemosiderin deposits. Wide endothelial intercellular gaps and incomplete basement membranes were seen by electron microscopy. Dilated, hyperplastic, lymphaticoid channels were prominent in one tumor. KHE in 14 infants was treated with interferon alpha-2a: 6 had accelerated regression; 2 had stabilization of growth; and 6 evidenced no response. The mortality rate was 24 percent (5 of 21); this included three infants with retroperitoneal KHE. Kasabach-Merritt phenomenon does not occur with common hemangioma. Rather it is associated with the more aggressive KHE and rarely with other vascular neoplasms. Variable response to current pharmacologic therapy underscores our inadequate knowledge of the pathogenesis of thrombocytopenia in KHE.

Childhood moyamoya disease: hemodynamic MRI

BACKGROUND

Childhood moyamoya disease is a rare progressive cerebrovascular disease.

OBJECTIVE

To evaluate cerebral hemodynamics using dynamic Gd-DTPA-enhanced imaging in children with moyamoya disease.

MATERIALS AND METHODS

Eight children (2-11 years of age) with the clinical and angiographic findings typical of moyamoya disease, before and/or after surgical intervention (pial synangiosis), underwent conventional MR imaging (MRI) and hemodynamic MR imaging (HMRI). HMRI used a spoiled gradient-echo with low flip angle (10 deg) and long TE (TR/TE = 24/15 ms) to minimize T 1 effects and emphasize T 2* weighting. Raw and calculated hemodynamic images were reviewed. Three-dimensional time-of-flight MR angiography (MRA) and perfusion brain single photon emission computed tomography (SPECT) were also performed.

RESULTS

Abnormal hemodynamic maps resulting from vascular stenosis or occlusion and basal collaterals were observed in six patient studies. HMRI depicted perfusion dynamics of affected cerebrovascular territories, detected cortical perfusion deficits, and complemented conventional MRI and MRA. HMRI findings were consistent with those of catheter angiography and perfusion SPECT.

CONCLUSION

Our preliminary experience suggests that HMRI may be of value in the preoperative and postoperative evaluation of surgical interventions in moyamoya disease.

Renovascular hypertension in Marfan syndrome

A defect in fibrillin integrity predisposes patients with Marfan syndrome to vascular wall abnormalities, most notably aortic rupture and dissection. Renal vascular anomalies have not been described previously in children with Marfan syndrome. In this report, we detail data from a hypertensive 14-year-old girl with clinical stigmata of Marfan syndrome and a diagnostic evaluation significant for characteristic aortic root dilatation and aneurysm, as well as a disparity in renal size and function exacerbated by captopril administration. Renal arteriography confirmed a left main renal artery stenosis that was not amendable to balloon angioplasty. Surgical resection resulted in significant improvement in hypertension. Pathological examination of the resected renal artery segment revealed intimal proliferation, fragmentation of the elastic media, and inner medial dissection. This patient demonstrates that, in addition to the aorta, renal arteries can be affected with the characteristic vascular wall pathology of Marfan syndrome, resulting in systemic hypertension. These data suggest that children with Marfan syndrome and hypertension need to be evaluated carefully for the presence of renal anomalies.

Angiographic changes after pial synangiosis in childhood moyamoya disease

PURPOSE

To describe the angiographic changes accompanying the surgical treatment of moyamoya disease by pial synangiosis and to compare these changes with patient outcome.

METHODS

The preoperative and postoperative cerebral angiograms, MR images, and clinical records of 13 children treated with pial synangiosis for moyamoya disease were reviewed.

RESULTS

After synangiosis, 10 patients had significant neurologic improvement and three had minimal or no improvement. Postoperative MR images showed no new infarctions. Well-developed (grade A or B) transpial or transdural collaterals to the brain were present at the site of synangiosis in 84% of the surgically treated hemispheres. Cerebrovascular occlusive changes increased postoperatively in 76% of hemispheres. After synangiosis, moyamoya collaterals were increased in 48%, unchanged in 16%, and decreased in 36% of surgically treated hemispheres. All 10 patients with grade A or B collaterals bilaterally after synangiosis were asymptomatic or improved on follow-up.

CONCLUSION

Pial synangiosis typically results in an increase in collaterals from the superficial temporal artery or middle meningeal artery to the brain. Synangiosis appears to result in stabilization or improvement in neurologic symptoms but does not prevent the angiographic progression of disease or the development of moyamoya collaterals. The angiographic demonstration of well-formed collaterals after synangiosis is associated with a favorable clinical outcome.

High-external-quantum-efficiency organic light-emitting devices

We study the internal and external quantum efficiencies of vacuum-deposited organic light-emitting devices (OLED's). The internal quantum efficiency of OLED's based on tris-(8-hydroxyquinoline) aluminum is calculated to be 5.7 times the observed external quantum efficiency ?(e), consistent with measurements. We demonstrate a shaped substrate that increases ?(e) by a factor of 1.9+/-0.2 over similar OLED's fabricated upon flat glass substrates and leads to a 100%-emissive aperture, i.e., the emitting area completely occupies the display area even in the presence of metal interconnects. We also discuss a substrate structure that increases ?(e) by an additional factor of 2. The high device efficiencies are promising for developing OLED-based displays with extremely low power consumption and increased operational lifetime.

Vacuum-deposited, nonpolymeric flexible organic light-emitting devices

We demonstrate mechanically flexible, organic light-emitting devices (OLED's) based on the nonpolymetric thin-film materials tris-(8-hydroxyquinoline) aluminum (Alq(3)) and N, N(?) -diphenyl- N, N(?) -bis(3-methylphenyl)1- 1(?) biphenyl-4, 4(?) diamine (TPD). The single heterostructure is vacuum deposited upon a transparent, lightweight, thin plastic substrate precoated with a transparent, conducting indium tin oxide thin film. The flexible OLED performance is comparable with that of conventional OLED's deposited upon glass substrates and does not deteriorate after repeated bending. The large-area (~1 - cm>(2)) devices can be bent without failure even after a permanent fold occurs if they are on the convex substrate surface or over a bend radius of ~0.5>cm if they are on the concave surface. Such devices are useful for ultralightweight, flexible, and comfortable full-color flat panel displays.

Venous malformation of the pediatric airway

OBJECTIVE

To evaluate the management of venous malformations of the pediatric airway, including diagnostic criteria and response to sclerotherapy and laser photocoagulation.

DESIGN

Case series analysis of eight patients diagnosed with venous malformations of the upper airway.

SETTING

Academic, tertiary care, children's hospital.

PATIENTS

Eight patients (3 female, 5 male) with congenital venous malformations of the upper airway.

INTERVENTION

Each patient underwent an individualized treatment regimen of sclerotherapy, laser photocoagulation and/or surgery.

RESULTS

The combination of sclerotherapy and laser photocoagulation appears to cause gradual regression of the malformation. Five of the eight patients will require further therapy; two patients remain tracheotomy dependent.

CONCLUSIONS

Extensive venous malformations of the pediatric airway require staged therapy, with a combination of sclerotherapy and photocoagulation. Long-term follow-up is essential because of the natural history of these lesions.

Hepatic vascular anomalies in infancy: a twenty-seven-year experience

OBJECTIVE

Infantile hemangioma and arteriovenous malformation (AVM) of the liver have a similar presentation but a different natural history, and therefore require different treatment. This study was undertaken to clarify differential diagnosis and management of these two biologically distinct vascular disorders.

STUDY DESIGN

We retrospectively analyzed the records of 43 children with hepatic vascular anomalies treated during the past 27 years.

RESULTS

Ninety percent were hemangiomas (n = 39); 10% were AVM (n = 4). Infants with AVM or large solitary hemangioma had hepatomegaly, congestive heart failure, and anemia as presenting symptoms at birth. Multiple hepatic hemangiomas manifested at 1 to 16 weeks of age with the same clinical triad, plus multiple cutaneous lesions (19/23). The mortality rate after treatment of hepatic AVM was 50% (2/4). The mortality rates after treatment of liver hemangiomas were as follows: resection of solitary lesions, 20% (2/10); embolization, 43% (3/7); corticosteroids, 30% (3/10); and interferon alfa-2a, 15% (2/13).

CONCLUSION

Solitary hepatic hemangioma cannot always be distinguished from hepatic AVM without radiologic studies. Multiple hepatic hemangiomas are differentiated from hepatic AVM by coexistence of multiple cutaneous hemangioma and by radiologic imaging. We recommend combined embolization and surgical resection for hepatic AVM and for solitary symptomatic hemangioma, if drug therapy fails. Pharmacologic treatment is used for symptomatic multiple liver hemangiomas. Embolization allows interim control of heart failure. A decreased mortality rate after interferon alfa-2a therapy is encouraging.