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1.
Interv Neuroradiol ; 18(2): 153-7, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22681729

ABSTRACT

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.


Subject(s)
Arteriovenous Malformations/complications , Developmental Disabilities/complications , Eye Abnormalities/complications , Sinus Pericranii/complications , Arteriovenous Malformations/diagnosis , Cerebral Angiography , Child , Child, Preschool , Developmental Disabilities/diagnosis , Eye Abnormalities/diagnosis , Humans , Magnetic Resonance Imaging , Male , Sinus Pericranii/diagnosis , Tomography, X-Ray Computed
2.
AJNR Am J Neuroradiol ; 32(10): 1812-7, 2011.
Article in English | MEDLINE | ID: mdl-21310861

ABSTRACT

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.


Subject(s)
Abnormalities, Multiple/pathology , Arteriovenous Malformations/pathology , Magnetic Resonance Imaging , Spinal Cord/abnormalities , Spinal Cord/pathology , Spine/abnormalities , Spine/pathology , Adolescent , Child, Preschool , Female , Humans , Male , Syndrome
3.
AJNR Am J Neuroradiol ; 31(9): 1608-12, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20651014

ABSTRACT

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.


Subject(s)
Arteriovenous Malformations/diagnostic imaging , Arteriovenous Malformations/epidemiology , Klippel-Trenaunay-Weber Syndrome/diagnostic imaging , Klippel-Trenaunay-Weber Syndrome/epidemiology , Spinal Cord/abnormalities , Spinal Cord/blood supply , Child , Child, Preschool , Comorbidity , Female , Humans , Incidence , Infant, Newborn , Male , Radiography , Risk Assessment , Risk Factors
4.
AJNR Am J Neuroradiol ; 31(4): 775-9, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20007727

ABSTRACT

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.


Subject(s)
Arteriovenous Malformations/genetics , Chromosome Aberrations , DNA Mutational Analysis , Genes, Dominant/genetics , Spinal Cord/blood supply , p120 GTPase Activating Protein/genetics , Adult , Angiography , Arteriovenous Malformations/diagnosis , Arteriovenous Malformations/therapy , Child , Child, Preschool , Combined Modality Therapy , Embolization, Therapeutic , Female , Follow-Up Studies , Genotype , Hemangioma, Capillary/diagnosis , Hemangioma, Capillary/genetics , Hemangioma, Capillary/therapy , Humans , Infant , Magnetic Resonance Imaging , Male , Microsurgery , Neoplasms, Multiple Primary/diagnosis , Neoplasms, Multiple Primary/genetics , Neoplasms, Multiple Primary/therapy , Neurologic Examination , Postoperative Complications/diagnosis , Skin Neoplasms/diagnosis , Skin Neoplasms/genetics , Skin Neoplasms/therapy , Spinal Cord Compression/diagnosis , Spinal Cord Compression/genetics , Spinal Cord Compression/therapy , Young Adult
5.
AJNR Am J Neuroradiol ; 30(5): 1005-13, 2009 May.
Article in English | MEDLINE | ID: mdl-19213817

ABSTRACT

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.


Subject(s)
Brain Neoplasms/diagnosis , Diagnostic Imaging/methods , Hemangioma/diagnosis , Spinal Neoplasms/diagnosis , Diagnosis, Differential , Female , Humans , Infant , Infant, Newborn , Male
6.
AJNR Am J Neuroradiol ; 28(2): 335-41, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17297008

ABSTRACT

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.


Subject(s)
Arteriovenous Malformations/pathology , Cerebral Veins/abnormalities , Hemangioma, Cavernous, Central Nervous System/pathology , Lymphangioma/pathology , Orbital Neoplasms/pathology , Adolescent , Adult , Arteriovenous Malformations/diagnostic imaging , Arteriovenous Malformations/epidemiology , Cerebral Angiography , Cerebral Veins/diagnostic imaging , Child , Child, Preschool , Female , Hemangioma, Cavernous, Central Nervous System/diagnostic imaging , Hemangioma, Cavernous, Central Nervous System/epidemiology , Humans , Incidence , Infant , Infant, Newborn , Lymphangioma/diagnostic imaging , Lymphangioma/epidemiology , Magnetic Resonance Imaging , Male , Orbital Neoplasms/diagnostic imaging , Orbital Neoplasms/epidemiology , Retrospective Studies , Tomography, X-Ray Computed
7.
AJNR Am J Neuroradiol ; 27(9): 1927-9, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17032868

ABSTRACT

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.


Subject(s)
Central Nervous System Vascular Malformations/diagnosis , Central Nervous System Vascular Malformations/genetics , Cerebral Angiography , Chromosome Aberrations , DNA Mutational Analysis , Genes, Dominant/genetics , Intracranial Arteriovenous Malformations/diagnosis , Magnetic Resonance Angiography , Magnetic Resonance Imaging , PTEN Phosphohydrolase/genetics , Base Pairing/genetics , Child , DNA Transposable Elements/genetics , Dominance, Cerebral/physiology , Exons/genetics , Frameshift Mutation , Humans , Intracranial Arteriovenous Malformations/genetics , Male , Sinus Thrombosis, Intracranial/diagnosis , Sinus Thrombosis, Intracranial/genetics , Syndrome
8.
Interv Neuroradiol ; 8(3): 227-34, 2002 Sep 30.
Article in English | MEDLINE | ID: mdl-20594480

ABSTRACT

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.

9.
AJR Am J Roentgenol ; 177(6): 1359-63, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11717083

ABSTRACT

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.


Subject(s)
Blood Coagulation Disorders/etiology , Embolization, Therapeutic/adverse effects , Sclerotherapy/adverse effects , Adolescent , Adult , Blood Coagulation Disorders/drug therapy , Child , Child, Preschool , Ethanol/therapeutic use , Female , Humans , Infant , Infant, Newborn , Male , Pilot Projects , Prospective Studies , Sodium Tetradecyl Sulfate/therapeutic use
10.
Pediatr Radiol ; 31(8): 533-45, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11550763

ABSTRACT

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.


Subject(s)
Arteriovenous Fistula/diagnosis , Hemangioma/diagnosis , Hepatic Artery/abnormalities , Liver Neoplasms/diagnosis , Portal Vein/abnormalities , Vascular Neoplasms/diagnosis , Adolescent , Arteriovenous Malformations/diagnosis , Child , Hemangioma/therapy , Hemangiosarcoma/diagnosis , Humans , Infant , Liver/diagnostic imaging , Liver/pathology , Liver Neoplasms/therapy , Magnetic Resonance Imaging , Radiography , Vascular Neoplasms/therapy
11.
Pediatr Radiol ; 31(7): 507-14, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11486806

ABSTRACT

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.


Subject(s)
Angiography , Arm/blood supply , Magnetic Resonance Imaging , Veins/abnormalities , Adolescent , Adult , Angiography/methods , Arm/diagnostic imaging , Child , Child, Preschool , Female , Humans , Infant , Male
12.
J Pediatr Surg ; 36(8): 1269-72, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11479874

ABSTRACT

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.


Subject(s)
Chylothorax/surgery , Thoracic Duct/abnormalities , Thoracic Duct/surgery , Adolescent , Child , Chylothorax/diagnosis , Chylothorax/etiology , Critical Illness , Follow-Up Studies , Humans , Infant , Laparotomy/methods , Male , Risk Assessment , Severity of Illness Index , Tomography, X-Ray Computed , Treatment Outcome
13.
J Am Chem Soc ; 123(18): 4304-12, 2001 May 09.
Article in English | MEDLINE | ID: mdl-11457197

ABSTRACT

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.

14.
AJR Am J Roentgenol ; 177(2): 427-30, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11461876

ABSTRACT

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.


Subject(s)
Diagnostic Imaging , Hypnotics and Sedatives/administration & dosage , Midazolam/administration & dosage , Pentobarbital/administration & dosage , Child, Preschool , Databases, Factual , Female , Humans , Hypnotics and Sedatives/therapeutic use , Infant , Injections, Intravenous , Male , Midazolam/therapeutic use , Pentobarbital/therapeutic use , Prospective Studies , Time Factors
15.
J Am Chem Soc ; 123(26): 6300-7, 2001 Jul 04.
Article in English | MEDLINE | ID: mdl-11427054

ABSTRACT

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.

16.
Plast Reconstr Surg ; 107(7): 1647-54, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11391180

ABSTRACT

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.


Subject(s)
Hemangioma/congenital , Skin Neoplasms/congenital , Adolescent , Adult , Angiography , Child , Child, Preschool , Female , Hemangioma/pathology , Humans , Magnetic Resonance Imaging , Male , Retrospective Studies , Skin Neoplasms/pathology
17.
Lancet ; 357(9263): 1177-8, 2001 Apr 14.
Article in English | MEDLINE | ID: mdl-11323047

ABSTRACT

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.


Subject(s)
Brain/abnormalities , Brain/embryology , Fetus/anatomy & histology , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Congenital Abnormalities/diagnosis , Female , Humans , Magnetic Resonance Imaging/methods , Pregnancy , Prenatal Diagnosis
18.
Paediatr Anaesth ; 11(2): 228-32, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11240884

ABSTRACT

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.


Subject(s)
Congenital Hypothyroidism , Hemangioma/surgery , Liver Neoplasms/surgery , Preoperative Care , Anesthesia, General , Decompression, Surgical , Embolization, Therapeutic , Hemangioma/complications , Hemangioma/congenital , Humans , Hypothyroidism/complications , Hypothyroidism/drug therapy , Infant , Infusions, Intravenous , Laparotomy , Liver Neoplasms/complications , Liver Neoplasms/congenital , Male , Triiodothyronine/administration & dosage
19.
Cardiovasc Intervent Radiol ; 24(5): 343-46, 2001.
Article in English | MEDLINE | ID: mdl-11815842

ABSTRACT

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.


Subject(s)
Angioplasty, Balloon , Hypertension, Renovascular/etiology , Renal Artery Obstruction/complications , Renal Artery Obstruction/therapy , Adolescent , Female , Humans , Hypertension, Renovascular/therapy , Recurrence
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