Endothelial cilia dysfunction in pathogenesis of hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is associated with defective capillary network, leading to dilated superficial vessels and arteriovenous malformations (AVMs) in which arteries connect directly to the veins. Loss or haploinsufficiency of components of TGF-β signaling, ALK1, ENG, SMAD4, and BMP9, have been implicated in the pathogenesis AVMs. Emerging evidence suggests that the inability of endothelial cells to detect, transduce and respond to blood flow, during early development, is an underpinning of AVM pathogenesis. Therefore, components of endothelial flow detection may be instrumental in potentiating TGF-β signaling in perfused blood vessels. Here, we argue that endothelial cilium, a microtubule-based and flow-sensitive organelle, serves as a signaling hub by coupling early flow detection with potentiation of the canonical TGF-β signaling in nascent endothelial cells. Emerging evidence from animal models suggest a role for primary cilia in mediating vascular development. We reason, on recent observations, that endothelial cilia are crucial for vascular development and that embryonic loss of endothelial cilia will curtail TGF-β signaling, leading to associated defects in arteriovenous development and impaired vascular stability. Loss or dysfunction of endothelial primary cilia may be implicated in the genesis of AVMs due, in part, to inhibition of ALK1/SMAD4 signaling. We speculate that AVMs constitute part of the increasing spectrum of ciliopathy-associated vascular defects.

Scarring in Patients With PIK3CA-Related Overgrowth Syndromes

Importance

Patients with somatic overgrowth commonly require surgical intervention to preserve function and improve cosmesis. To our knowledge no observation of scarring outcomes in this population has been published to date.

Objective

To observe the frequency of abnormal scarring in patients with somatic overgrowth and sequencing-verified mutations in the PIK3CA gene.

Design, Setting, and Participants

This retrospective study evaluated scarring outcomes in patients with PIK3CA-related overgrowth. Samples of affected tissue were sequenced between July 2015 and October 2016. Medical records from multiple large academic tertiary care centers were reviewed for surgical history and scar descriptions, and clinical photographs were assessed by 2 surgeons (J.N.J. and D.M.K.) to confirm abnormal scarring. Analysis of medical records and photographs was performed between April 2017 and June 2017 by a multidisciplinary team from dermatology, plastic surgery, orthopedic surgery, radiology, and genetics departments. All patients considered for the study were diagnosed with somatic overgrowth and previously had affected tissue sent for next-generation sequencing. Those with pathogenic PIK3CA variants and 1 or more prior surgical procedures were reviewed.

Main Outcomes and Measures

Presence of excessive scarring in patients with PIK3CA overgrowth.

Results

A total of 57 patients with segmental overgrowth syndromes were sequenced. Of the 57 patients, 25 (44%) had pathogenic or likely pathogenic variants in PIK3CA. Of those with pathogenic PIK3CA variants, 6 (24%) had past surgical procedures, all with preoperative and postoperative photographs. Of 6 patients with PIK3CA-related overgrowth and a history of 1 or more surgical procedure, 4 (67%) developed excessive scarring. The cohort with abnormal scarring comprised 3 females and 1 male, with a median age of 8.5 years. All abnormal scarring occurred in affected overgrowth tissue. Three of the 4 patients developed the excessive scarring after debulking procedures for overgrowth and/or vascular malformations of the upper or lower extremity.

Conclusions and Relevance

Excessive scarring occurred frequently in patients with PIK3CA-related overgrowth syndromes. The risk of abnormal scarring should therefore be discussed preoperatively. Given the activating nature of these PIK3CA variants, we suggest that the excessive scarring may be owing in part to up-regulation of the PI3K-Akt-mTOR pathway. Additional studies are needed to assess scarring outcomes in patients with other types of overgrowth.

Lymphaticovenous bypass of the thoracic duct for the treatment of chylous leak in central conducting lymphatic anomalies

BACKGROUND

Central conducting lymphatic anomalies (CCLA) may cause chylous leaks and protein-losing enteropathy (PLE) owing to dysfunction of the central lymphatic channels. Most of the treatment strategies for these conditions are palliative and provide transient improvement.

METHODS

We treated 14 patients with intractable chylous leak and/or PLE using a novel technique of lymphaticovenous bypass of the terminal portion of the thoracic duct. Chylous leaks occurred in multiple different anatomic sites. All patients had CCLA and failure of thoracic duct emptying demonstrated by preoperative intranodal lymphangiography.

RESULTS

Five patients had complete resolution of symptoms, and two patients had partial improvement. There were no major complications. Of 5 patients with PLE, only one improved after lymphaticovenous bypass. Repeat traditional lymphangiography was performed in 4 patients who did not improve, demonstrating patency of the bypass in all cases with persistent sluggish drainage. One patient had repeat MR lymphangiography that did not show the thoracic duct well.

CONCLUSIONS

Bypass of the terminal thoracic duct is a novel procedure that offers improvement and a chance of cure for some patients with devastating manifestations of CCLA who lack other effective therapeutic options.

LEVEL OF EVIDENCE

IV.

Characterization of Endothelial Cilia Distribution During Cerebral-Vascular Development in Zebrafish ( Danio rerio)

Objective- Endothelial cells (ECs) sense and respond to flow-induced mechanical stress, in part, via microtubule-based projections called primary cilia. However, many critical steps during vascular morphogenesis occur independent of flow. The involvement of cilia in regulating these stages of cranial vascular morphogenesis is poorly understood because cilia have not been visualized in primary head vessels. The objective of this study was to investigate involvement of cilia in regulating the early stages of cranial vascular morphogenesis. Approach and Results- Using high-resolution imaging of the Tg(kdrl:mCherry-CAAX) y171 ;(bactin::Arl13b:GFP) zebrafish line, we showed that cilia are enriched in the earliest formed cranial vessels that assemble via vasculogenesis and in angiogenic hindbrain capillaries. Cilia were more prevalent around the boundaries of putative intravascular spaces in primary and angiogenic vessels. Loss of cardiac contractility and blood flow, because of knockdown of cardiac troponin T type 2a ( tnnt2a) expression, did not affect the distribution of cilia in primary head vasculature. In later stages of development, cilia were detected in retinal vasculature, areas of high curvature, vessel bifurcation points, and during vessel anastomosis. Loss of genes crucial for cilia biogenesis ( ift172 and ift81) induced intracerebral hemorrhages in an EC-autonomous manner. Exposure to high shear stress induced premature cilia disassembly in brain ECs and was associated with intracerebral hemorrhages. Conclusions- Our study suggests a functional role for cilia in brain ECs, which is associated with the emergence and remodeling of the primary cranial vasculature. This cilia function is flow-independent, and cilia in ECs are required for cerebral-vascular stability.

Combined Nd:YAG laser and bleomycin sclerotherapy under the same anesthesia for cervicofacial venous malformations: A safe and effective treatment option

INTRODUCTION

Extensive cervicofacial venous malformations (VM) pose significant challenges to a patient's quality of life (altered breathing, dysphagia, dysarthria). Treatment options include: 1) Surgical debulking; 2) Sclerotherapy; 3) laser therapy; or 4) Combined modalities. Recent studies have demonstrated the importance of multimodality and multidisciplinary management of these patients. However, no studies have described combined single anesthetic laser and sclerotherapy treatment. We sought to demonstrate the safety and efficacy of combined Nd:YAG laser and sclerotherapy under the same anesthetic administration.

METHODS

Retrospective review of 8 patients (Age 6 mo -74 yrs, x͂ 31) with extensive cervicofacial VM with significant airway involvement. Patients were treated with combined suspension laryngoscopy with Nd:YAG laser of airway VM followed by image guided direct puncture sclerotherapy using bleomycin in the airway VM and sodium tetradecyl sulfate (STS) foam in the cervicofacial VM during the same anesthetic encounter.

RESULTS

All 8 patients had extensive cervicofacial VMs that were symptomatic with snoring or orthopnea. Four of the patients had previously been treated at outside institutions with residual disease or significant complications. All patients remained intubated post procedure (Avg. 1.07 days) and tolerated extubation without re-intubation or any major complications. The average length of hospital stay was 3.2 days, of which 1.9 days were spent in the ICU. Patients reported symptomatic improvement or had decreased VM disease on MRI follow up.

CONCLUSION

Combined Nd:YAG laser therapy and sclerotherapy allows treatment of both superficial and deep components of VMs in a safe and efficient manner. In addition, suspension laryngoscopy provides improved visualization and access for the interventional radiologist in difficult to reach areas for sclerotherapy.

Somatic second hit mutation of RASA1 in vascular endothelial cells in capillary malformation-arteriovenous malformation

Capillary malformation-arteriovenous malformation (CM-AVM) is an autosomal dominant vascular disorder that is associated with inherited inactivating mutations of the RASA1 gene in the majority of cases. Characteristically, patients exhibit one or more focal cutaneous CM that may occur alone or together with AVM, arteriovenous fistulas or lymphatic vessel abnormalities. The focal nature and varying presentation of lesions has led to the hypothesis that somatic "second hit" inactivating mutations of RASA1 are necessary for disease development. In this study, we examined CM from four different CM-AVM patients for the presence of somatically acquired RASA1 mutations. All four patients were shown to possess inactivating heterozygous germline RASA1 mutations. In one of the patients, a somatic inactivating RASA1 mutation (c.1534C > T, p.Arg512*) was additionally identified in CM lesion tissue. The somatic RASA1 mutation was detected within endothelial cells specifically and was in trans with the germline RASA1 mutation. Together with the germline RASA1 mutation (c.2125C > T, p.Arg709*) in the same patient, the endothelial cell somatic RASA1 mutation likely contributed to lesion development. These studies provide the first clear evidence of the second hit model of CM-AVM pathogenesis.

Angioarchitecture of Hereditary Arteriovenous Malformations

This article describes three hereditary conditions known to be associated with arteriovenous malformation (AVM), along with their clinical and imaging features and angiographic angioarchitecture. Hereditary hemorrhagic telangiectasia, capillary malformation-AVM (CM-AVM), and PTEN tumor hamartoma syndrome are conditions with autosomal dominant inheritance, caused by mutations in different molecular pathways, which frequently present with symptomatic AVMs. Imaging biomarkers, including sites of predilection, angioarchitecture, and tissue overgrowth patterns, are helpful in identifying these patients and selecting appropriate treatment.

RASA1 mutations and associated phenotypes in 68 families with capillary malformation-arteriovenous malformation

Capillary malformation-arteriovenous malformation (CM-AVM) is an autosomal-dominant disorder, caused by heterozygous RASA1 mutations, and manifesting multifocal CMs and high risk for fast-flow lesions. A limited number of patients have been reported, raising the question of the phenotypic borders. We identified new patients with a clinical diagnosis of CM-AVM, and patients with overlapping phenotypes. RASA1 was screened in 261 index patients with: CM-AVM (n = 100), common CM(s) (port-wine stain; n = 100), Sturge-Weber syndrome (n = 37), or isolated AVM(s) (n = 24). Fifty-eight distinct RASA1 mutations (43 novel) were identified in 68 index patients with CM-AVM and none in patients with other phenotypes. A novel clinical feature was identified: cutaneous zones of numerous small white pale halos with a central red spot. An additional question addressed in this study was the "second-hit" hypothesis as a pathophysiological mechanism for CM-AVM. One tissue from a patient with a germline RASA1 mutation was available. The analysis of the tissue showed loss of the wild-type RASA1 allele. In conclusion, mutations in RASA1 underscore the specific CM-AVM phenotype and the clinical diagnosis is based on identifying the characteristic CMs. The high incidence of fast-flow lesions warrants careful clinical and radiologic examination, and regular follow-up.

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.

Oral rapamycin in the treatment of patients with hamartoma syndromes and PTEN mutation

Bannayan-Riley-Ruvacalba syndrome (BRRS) belongs to the PTEN hamartoma tumor syndromes and is characterized by a high risk of malignancy in early adulthood added to local destructive effects of hamartomas in childhood. There is no standard treatment for this condition and patients are usually offered symptomatic surgical relief. Rapamycin has been reported to be effective in the management of other conditions associated with PTEN mutation. We report here a case of BRRS in a 6-year-old male with progressive loss of function of left hand and forearm associated with pain. He was treated with oral rapamycin and regained pain-free full mobility.

Vascular malformations involving the female pelvis

Vascular malformations (VM) are classified by flow characteristics and channel content. They can involve any organ and tissue plane, and occur in focal and diffuse forms. Slow-flow vascular malformations (venous and lymphatic malformations) are typically treated by sclerotherapy, whereas fast-flow lesions (arteriovenous malformations) are managed with embolizations. Some VMs, such as VMs of the rectum or uterus, are best dealt with surgically. This review will present a summary of the conditions, their imaging features, and some useful endovascular therapeutic techniques.

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.

LUMBAR: association between cutaneous infantile hemangiomas of the lower body and regional congenital anomalies

OBJECTIVE

To define the clinical spectrum of regional congenital anomalies associated with large cutaneous hemangiomas of the lower half of the body, clarify risk for underlying anomalies on the basis of hemangioma location, and provide imaging guidelines for evaluation.

STUDY DESIGN

We conducted a multi-institutional, retrospective case analysis of 24 new patients and review of 29 published cases.

RESULTS

Hemangiomas in our series tended to be "segmental" and often "minimal growth" in morphology. Such lesions were often extensive, covering the entire leg. Extensive limb hemangiomas also showed potential for extracutaneous anomalies, including underlying arterial anomalies, limb underdevelopment, and ulceration. The cutaneous hemangioma and underlying anomalies demonstrated regional correlation. Myelopathies were the most common category of associated anomalies.

CONCLUSIONS

We propose the acronym "LUMBAR" to describe the association of Lower body hemangioma and other cutaneous defects, Urogenital anomalies, Ulceration, Myelopathy, Bony deformities, Anorectal malformations, Arterial anomalies, and Renal anomalies. There are many similarities between LUMBAR and PHACE syndrome, which might be considered regional variations of the same. Although guidelines for imaging are suggested, prospective studies will lead to precise imaging recommendations and help determine true incidence, risk and long-term outcomes.

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.

Portomesenteric venous thrombosis associated with rectal venous malformations

PURPOSE

We report thrombosis of portal and mesenteric veins in patients with a pattern of rectal venous malformations (VMs) and ectatic major mesenteric veins.

METHODS

Eight patients having rectal VMs with either ectatic mesenteric veins and/or evidence of portomesenteric venous thrombosis (PVT), evaluated from 1995-2009, were reviewed.

RESULTS

Portomesenteric venous thrombosis was evident in 5 patients at presentation. Three had patent ectatic mesenteric veins, 2 with demonstrated reversal of flow, and 2 of whom went on to thrombosis during observation. Six patients developed portal hypertension. Five remain on long-term anticoagulation. After recognizing this pattern, one patient underwent preemptive proximal ligation of the inferior mesenteric vein (IMV) to enhance antegrade portal vein flow and prevent propagation or embolization of venous thrombus from the IMV to the portal vein.

CONCLUSION

Rectal VMs should be evaluated for associated ectatic mesenteric veins. The ectatic vein siphons flow from the portal vein down to the rectal VM, leading to stagnation of blood in the portal vein and resultant thrombosis. Primary thrombosis in the stagnant rectal VM and/or mesenteric vein can also predispose to embolization up into the portal vein. This pattern of rectal VM and ectatic mesenteric vein should be considered a risk factor for devastating PVT.

CLOVES syndrome with thoracic and central phlebectasia: increased risk of pulmonary embolism

OBJECTIVE

CLOVES syndrome (congenital lipomatous overgrowth, vascular malformations, epidermal nevi, and skeletal/scoliosis and spinal abnormalities) is a rare, complex overgrowth syndrome with serious morbidity. In this communication we studied the presence of central and thoracic phlebectasia in patients with CLOVES syndrome and its clinical implications.

METHODS

We conducted a comprehensive search of our databases at Children's Hospital Boston over the last 10 years (1999-2008) for patients with CLOVES syndrome and central and thoracic phlebectasia. Medical records, clinical photographs, and imaging studies of varying modalities were reviewed.

RESULTS

Review of the clinical data and imaging studies of 12 patients with CLOVES syndrome documented the presence of central and thoracic phlebectasia in 11 patients. Two patients had serious perioperative pulmonary embolism, and 1 died.

CONCLUSIONS

Central and thoracic phlebectasia in patients with CLOVES syndrome is common and increases the risk of pulmonary embolism. Aggressive prophylactic measures should be considered before major interventions.

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.

Parkes Weber syndrome, vein of Galen aneurysmal malformation, and other fast-flow vascular anomalies are caused by RASA1 mutations

Capillary malformation-arteriovenous malformation (CM-AVM) is a newly recognized autosomal dominant disorder, caused by mutations in the RASA1 gene in six families. Here we report 42 novel RASA1 mutations and the associated phenotype in 44 families. The penetrance and de novo occurrence were high. All affected individuals presented multifocal capillary malformations (CMs), which represent the hallmark of the disorder. Importantly, one-third had fast-flow vascular lesions. Among them, we observed severe intracranial AVMs, including vein of Galen aneurysmal malformation, which were symptomatic at birth or during infancy, extracranial AVM of the face and extremities, and Parkes Weber syndrome (PKWS), previously considered sporadic and nongenetic. These fast-flow lesions can be differed from the other two genetic AVMs seen in hereditary hemorrhagic telangiectasia (HHT) and in phosphatase and tensin homolog (PTEN) hamartomatous tumor syndrome. Finally, some CM-AVM patients had neural tumors reminiscent of neurofibromatosis type 1 or 2. This is the first extensive study on the phenotypes associated with RASA1 mutations, and unravels their wide heterogeneity.

Reticular infantile hemangioma of the limb can be associated with ventral-caudal anomalies, refractory ulceration, and cardiac overload

We describe six patients with an uncommon variant of infantile hemangioma that we have termed reticular, occurring in the extremity, which were associated with intractable ulceration, anogenito-urinary-sacral anomalies, and sometimes cardiac overload. The extreme end of the spectrum is exemplified by a male neonate who presented with a stained, enlarged, pulsatile lower extremity, and cardiac failure. He also had hepatic hemangiomas and ambiguous genitalia. Progressive soft tissue necrosis and bony destruction necessitated amputation. The histopathologic features differed from those of typical infantile hemangioma: infiltrative (not lobular) and involving fascia, muscle, and bone. The mid-spectrum is illustrated by five females with reticular infantile hemangioma of the lower limb, buttock, and perineum. Four of these infants had a ventral-caudal anomaly, including omphalocele, recto-vaginal fistula, solitary/duplex kidney, imperforate anus, and tethered cord; one infant also had hepatic hemangiomas. Deep ulcerations healed following corticosteroid therapy; one patient required skin graft for closure of a thigh wound. The minor end of the spectrum is exemplified a patchy lesion in the distal limb. The reticular variant of infantile hemangioma can be confused with other vascular anomalies in the limb, such as capillary malformation, cutis marmorata telangiectasia congenita, diffuse arteriovenous malformation (Parkes Weber syndrome) and capillary-lymphatico-venous malformation (Klippel-Trenaunay syndrome). The macular network-like appearance of the tumor and coexisting ventral-caudal structural anomalies is analogous to the association of posterior fossa brain malformations, hemangiomas, arterial anomalies, coarctation of the aorta and cardiac defects, and eye abnormalities association in the craniofacial region.

The spectrum of vascular anomalies in patients with PTEN mutations: implications for diagnosis and management

BACKGROUND

Mutations in the PTEN gene cause two disorders that predispose to cancer, Bannayan-Riley-Ruvalcaba and Cowden syndromes. Some patients with a PTEN mutation have only macrocephaly and autism, but they may still be at risk for neoplasms. Vascular anomalies occur in patients with a PTEN mutation, but they have not been systematically studied or precisely defined.

METHOD

We analysed the clinical and radiological features of the vascular anomalies in 26 patients with PTEN mutations who were either seen or had their medical records reviewed at Children's Hospital Boston.

RESULTS

All 23 patients who had their head circumference measured were macrocephalic, and all 13 male patients who were fully examined had penile freckling. Vascular anomalies were found in 14/26 (54%) of patients: 8/14 (57%) had multiple lesions and 11/13 (85%) who had cross-sectional imaging had intramuscular vascular lesions. Radiographic studies showed that 12/14 (86%) were fast-flow vascular anomalies, and angiography typically showed focal segmental dilatation of draining veins. Excessive ectopic fat in the vascular anomalies was present in 11/12 (92%) of patients on CT or MRI. Intracranial developmental venous anomalies (DVAs) were found in 8/9 (89%) of patients who had brain MRI with contrast.

CONCLUSIONS

Vascular anomalies in patients with a PTEN mutation are typically multifocal intramuscular combinations of fast-flow channels and ectopic fat. Cerebral DVAs are very common. PTEN mutational analysis should be considered for all macrocephalic patients with fast-flow vascular anomalies or multiple intracranial DVAs.

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.

Hepatic hemangiomas: subtype classification and development of a clinical practice algorithm and registry

PURPOSE

Hepatic hemangiomas, though histologically benign, may be associated with significant morbidity and mortality in afflicted infants. The literature presents much confusion regarding the natural history and treatment options for hepatic hemangiomas. Clinical manifestations range from asymptomatic self-limiting lesions to congestive heart failure associated with high-volume vascular shunting to fulminant hepatic failure with hypothyroidism, abdominal compartment syndrome, and death. There has been little rationale to choose among observation, corticosteroid, other pharmacologic agents, arterial embolization, hepatic artery ligation, resection, or liver transplantation for any given patient.

METHODS

We analyzed several recent retrospective radiologic analyses and pathologic studies to determine whether hepatic hemangiomas could be categorized, allowing prediction of their natural history and rational choice of therapies based upon their clinical presentation and radiographic appearance.

RESULTS

We propose that hepatic hemangiomas do not represent a single entity but, rather, 3 principle categories of lesions: focal, multifocal, and diffuse. Because these 2 categories represent different anatomical and physiologic variants, so, too, may they respond differently to previously anecdotally applied treatment regimens. With input from international multidisciplinary authorities on hemangiomas, we developed and proposed a clinical practice algorithm for the evaluation and management of hepatic hemangiomas. Toward that end, we propose a plan to institute a web-based international hepatic hemangioma registry. Participants in the registry could obtain no-cost centralized review of imaging studies (and histology if available) and guidance regarding the management algorithm from an established multidisciplinary team. In exchange, the registry will facilitate the acquisition of systematic clinical and imaging information.

CONCLUSION

Longitudinal observation of response to more directed treatment protocols may contribute greatly to the understanding of these potentially fatal tumors.

Value of bispectral index monitor in differentiating between moderate and deep Ramsay Sedation Scores in children

BACKGROUND

Pediatric patients who undergo diagnostic radiological imaging studies routinely require moderate or deep sedation to a Ramsay Sedation Score (RSS) of 4 or 5, respectively. The correlation between moderate and deep RSS and bispectral index (BIS) in children has never been validated. This study was designed to determine whether the BIS values correlate with RSS of children sedated for diagnostic imaging studies.

METHODS

After Institutional Review Board approval, data were prospectively collected on all children receiving pentobarbital alone for computed tomography or magnetic resonance imaging. On arrival in the recovery room, any child assigned a Ramsay score of 4 or 5 was subsequently monitored with the BIS. Receiver-operating characteristic (ROC) analysis was used to evaluate the discriminative ability of BIS in differentiating depth of anesthesia.

RESULTS

A total of 86 children over 1 year of age were enrolled. Children with Ramsay 4 (moderate) and Ramsay 5 (deep) sedation scores showed no significant difference in age or pentobarbital dose (mg.kg(-1)). BIS values followed a normal Gaussian-shaped distribution for both Ramsay scores. There was no significant difference in mean BIS values between the Ramsay groups (P = 0.64). There was a wide variation in BIS values (range of 31-90), which demonstrates that the BIS monitor does not correlate with the clinically assigned RSS depth of anesthesia in children. The ROC curve for BIS is equivalent to a line of nondiscrimination.

CONCLUSION

BIS has limited ability to distinguish between moderate and deep Ramsay sedation levels in children who receive pentobarbital sedation for diagnostic imaging studies.

Radiofrequency Ablation of Microcystic Lymphatic Malformation in the Oral Cavity

OBJECTIVE

To determine the efficacy and safety of radiofrequency (RF) ablation of vesicles and the resulting symptomatic control of microcystic lymphatic malformation (LM) in the oral cavity.

DESIGN

An institutional review board-approved retrospective study with follow-up telephone interview.

SETTING

Tertiary pediatric medical center. Patients Eleven children (6 girls and 5 boys), aged 4 to 16 years, presenting between August 1, 2002, and December 1, 2004. Intervention Radiofrequency ablation of LM in the oral cavity.

MAIN OUTCOME MEASURES

Symptoms related to LM, postoperative oral intake, and postoperative antibiotic requirements.

RESULTS

Eleven patients presented with microcystic LM involving the lips, tongue, floor of the mouth, or buccal mucosa. Complaints included bleeding, infection, swelling, vesicle formation, and malocclusion. Patients underwent RF ablation (coblation) of oral cavity lesions. Seven (64%) of the 11 patients were able to tolerate oral intake in the recovery room. The need for antibiotics was reduced after RF ablation. All patients related diminished bleeding, pain, infection, or vesicle formation, with more than half reporting a significant improvement (6 patients) or complete resolution (1 patient). Five (62%) of 8 parents stated that the improvement after RF ablation was superior to that following previous procedures.

CONCLUSIONS

Subtotal RF ablation of LM appears to be safe, with early postoperative oral intake and minimal postoperative pain. Further studies are needed to determine long-term control of LM.

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.

Percutaneous Sclerotherapy for Lymphatic Malformations: A Retrospective Analysis of Patient-evaluated Improvement

PURPOSE

To evaluate the midterm outcomes of percutaneous sclerotherapy of lymphatic malformations (LMs) as judged by patients.

MATERIALS AND METHODS

A 13-item survey questionnaire was sent to 74 patients who had undergone at least one sclerotherapy procedure in our hospital from January 1997 through January 2003. Information regarding the anatomic location, specific symptoms reported, history, treatment satisfaction, postprocedural complications, and number of treatment sessions was elicited. Four sclerosing agents (as single agents or in combination with other agents) were used: ethanol, sodium tetradecyl sulfate 3% (STS), OK-432, and doxycycline.

RESULTS

Fifty-five patients or their caregivers completed the survey. The patients' ages ranged from 6 months to 48 years at the time of the first procedure (mean, 12 y; median, 4 y). A majority of LMs were located in the cervicofacial region. The size and location of the lesion, recurrent infection, and pain were the most frequent indications for treatment. Fifty-one percent of these patients received sclerotherapy alone or in conjunction with surgery as primary treatment. Ethanol was the most common sclerosing agent used, followed by doxycycline, STS, and OK-432. Response varied with the type of LM, with 100%, 86%, and 43% of the patients reporting good to complete response for macrocystic, microcystic, and combined-type LMs, respectively. Skin blistering and ulcers were the most common complications. Permanent complications were uncommon and were largely related to ethanol use.

CONCLUSIONS

Percutaneous sclerotherapy provides effective midterm primary treatment for LMs. Treatment outcomes appear to vary according to the morphology of the malformation.

Vascular anomalies of the female external genitalia

BACKGROUND/PURPOSE

Vascular tumors and malformations are rare. This large series describes vascular anomalies of the female genitalia and their management.

METHODS

An international review board-approved retrospective database and a record review from 1994 through 2004 was conducted.

RESULTS

Of the 3186 female patients with a vascular anomaly, 82 (2.6%) had a lesion in the external genitalia. There were 60 malformations and 22 tumors. The most common malformations were combined capillary-lymphaticovenous, venous, and lymphatic. Tumors included 20 infantile hemangiomas, 1 kaposiform hemangioendothelioma, and 1 kaposiform lymphangioendothelioma. The referring diagnosis was incorrect in 56% of patients. Cutaneous stains, swelling, deformity, bleeding, fluid leakage, or infection were the prominent symptoms. Magnetic resonance imaging, ultrasonography, angiography, and computed tomography were used for diagnostic clarification. Malformation treatment consisted of sclerotherapy, embolization, and operative resection. Tumor management included observation, surgical excision, and antiangiogenic pharmacotherapy.

CONCLUSIONS

Vascular anomalies of the female external genitalia are uncommon, and the initial diagnosis is often inaccurate. Correct diagnosis using clinical and radiographic data is feasible and leads to meaningful intervention for these frequently devastating lesions. Whereas tumors may respond to excision or antiangiogenic drugs, malformations require ablation or resection. Evaluation and management of these lesions is complex and benefits from interdisciplinary care.

Extracellular matrix dynamics associated with tissue-engineered intravascular sclerotherapy

BACKGROUND

The extracellular dynamics after intravascular sclerotherapy with an injectable, fibroblast-based engineered construct is unknown.

METHODS

Rabbits underwent ethanol sclerotherapy of a jugular vein segment. Control animals (n = 40) underwent no further treatment or an acellular collagen hydrogel was injected. Experimental animals (n = 20) received a tissue-engineered construct. After 1, 2, 4, and 20 to 24 weeks, segments were evaluated for collagen, glycosaminoglycan (GAG), matrix metalloproteinase (MMP) 2 and 9, and tissue inhibitors of MMP (TIMPs) 1 and 2 and scored on a scale of 0 to 3. Groups and time points were compared using nonparametric statistical analysis.

RESULTS

Collagen content was higher in animals that received fibroblasts (P < .05). Glycosaminoglycan analysis showed a higher grade only at 1 week (P < .05). Collagen and GAG deposition were prominent at weeks 1 through 4, and decreased over time. Both MMP-2 and MMP-9 and TIMP-1 and TIMP-2 grade decreased with time (P < .01) in all groups, with no differences between groups.

CONCLUSION

Enhancement of intravascular sclerotherapy by tissue engineering stems, at least in part, from increased local deposition of collagen and GAG. MMP and TIMPs may play a role in recanalization after experimental sclerotherapy. Tissue engineering may be a valuable adjunct for the treatment of vascular malformations.

Adverse cardiovascular and respiratory events during sedation of pediatric patients for imaging examinations

PURPOSE

To retrospectively identify factors associated with an increased risk of adverse cardiovascular or respiratory events during sedation of pediatric patients for imaging examinations.

MATERIALS AND METHODS

This HIPAA-compliant study was institutional review board approved; the requirement for informed consent was waived. All sedation information--including patient demographics, medications (doses and routes of administration), time required to sedate and before discharge, American Society of Anesthesiologists physical status classification, adverse events, and failed sedations--was maintained in a computerized database. A review of the data on all patients sedated between 1997 and 2003 for magnetic resonance imaging, computed tomography, and interventional radiology revealed associated adverse respiratory events in 70 patients. Adverse respiratory event was defined as oxygen desaturation of at least 5%, pulmonary aspiration, and need for airway resuscitation. Adverse cardiovascular events were defined as cardiac arrest and hemodynamic changes requiring medical therapy. Adverse events were compared between sedation regimens--which included fentanyl, chloral hydrate, pentobarbital, and midazolam hydrochloride--by using the Fisher exact test. Multiple logistic regression analysis was applied to identify potential predictors of adverse events.

RESULTS

Among 16,467 sedations performed, 70 (0.4%) were associated with adverse respiratory events: 58 cases of oxygen desaturation, two pulmonary aspirations, 10 cases of airway resuscitation, and no cardiovascular events. Nearly 30% (n = 20) of the 70 patients who had an adverse event had a history of serious respiratory illness. Logistic regression analysis revealed that neither patient age, weight, or sex nor type of imaging procedure was associated with an increased risk of an adverse event. Use of a single sedation agent was associated with lower adverse event risk than was use of multiple agents (P < .001).

CONCLUSION

Consideration should be given to using single agents, avoiding the use of multidrug sedation regimens, and recognizing that a history of pulmonary disease could be associated with an increased risk of adverse respiratory events despite a currently stable respiratory state.

Increased expression of urinary matrix metalloproteinases parallels the extent and activity of vascular anomalies

OBJECTIVE

Matrix metalloproteinases (MMPs) and the angiogenic proteins basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) have been implicated in mechanisms of human cancer and metastasis. Assays were conducted on the urine of patients with vascular anomalies (tumors and malformations), relatively common and occasionally life-threatening disorders for which few therapies exist. We sought to determine whether these angiogenesis modulators are present in the urine and whether their expression is associated with the extent and clinical course of the vascular lesion.

METHODS

A total of 217 patients with vascular anomalies and 74 age-matched control subjects participated. Urinary MMP expression was determined by substrate gel electrophoresis. Urinary bFGF and VEGF levels were measured by enzyme-linked immunosorbent assay. Each patient was assigned to 1 of 2 categories (tumor or malformation) and 1 of 9 specific groups. Extent of the vascular lesion and activity were scored by a blinded clinician.

RESULTS

Urinary high molecular weight (hMW) MMPs and bFGF were significantly increased in patients with vascular tumors (53%) and vascular malformations (41%), compared with control subjects (22%). These percentages increased as a function of extent of the lesion and disease activity. hMW MMPs were increased in 4 groups: infantile hemangioma, other vascular neoplasms, lymphatic malformation and capillary-lymphaticovenous malformations, and extensive and unremitting capillary malformation and arteriovenous malformation. No significant differences among the groups were detected for low molecular weight MMPs or VEGF.

CONCLUSIONS

Expression patterns of hMW MMPs and bFGF in the urine of patients with tumors and malformations are consistent with their different clinical behavior. These data represent the first evidence that MMPs are elevated in the urine of children with vascular anomalies. These data also suggest that the increased expression of urinary MMPs parallels the extent and activity of vascular anomalies in children. In addition to tumors, vascular malformations are angiogenesis dependent, suggesting that progression of a vascular malformation might be suppressed by angiogenic inhibitors, which would target bFGF and MMPs.

Cutaneovisceral angiomatosis with thrombocytopenia

We describe 10 children with multiple vascular lesions of the skin and gastrointestinal tract associated with sustained, minor thrombocytopenia. In some children, there was involvement of the lung (n = 5), bone (n = 2), liver (n = 1), spleen (n = 1), and muscle (n = 1). The cutaneous lesions were congenital, multifocal, discrete, red-brown and variably blue macules and papules; in 3 children, a large dominant plaque was also present. All children developed hematemesis and/or melena and endoscopic evaluation revealed several to numerous small mucosal lesions that involved all levels of the gastrointestinal tract. Three of 5 children with pulmonary nodules had cough and 1 also had hemoptysis. Biopsies of cutaneous, gastrointestinal, and pulmonary lesions showed thin-walled, blood-filled vascular channels and variable endothelial hyperplasia. The endothelial nuclei were elongated, round, crescentic, or hobnailed. Cytoplasmic and extracellular periodic acid-Schiff positive deposits were often present in the zones of endothelial hyperplasia. The platelets were small in some children, suggesting a primary defect, possibly accounting for the thrombocytopenia. Gastrointestinal hemorrhage and hemoptysis required antiangiogenic therapy. The constellation of findings defines a congenital proliferative disorder of blood vessels with a distinctive microscopic appearance. We have termed this relatively indolent or slowly progressive disorder cutaneovisceral angiomatosis with thrombocytopenia because this designation incorporates its major clinical and histopathologic features.

Iliac artery stenosis in a child with cutis marmorata telangiectatica congenita

Cutis marmorata telangiectatica congenita (CMTC) is a rare congenital disorder. We describe an 8-year-old boy with CMTC who presented with symptomatic claudication and diminished distal pulses. Imaging showed severe stenosis of the right common iliac artery, and the child underwent uncomplicated ilio-iliac bypass using prosthetic graft. This is the first report of a patient with CMTC and major vessel stenosis, successfully treated with a prosthetic graft bypass.

An injectable tissue-engineered embolus prevents luminal recanalization after vascular sclerotherapy

BACKGROUND/PURPOSE

Sclerotherapy for vascular malformations is often limited by luminal recanalization. This study examined whether an injectable tissue-engineered construct could prevent this complication in a rabbit model of venous sclerotherapy.

METHODS

Ethanol sclerotherapy of a temporarily occluded jugular vein segment was performed in 46 rabbits, which were then divided into 3 groups. Group I (n = 16) had no further manipulations. In groups II (n = 15) and III (n = 15), 0.5 mL collagen hydrogel was injected intraluminally, respectively, devoid of and seeded with autologous fibroblasts. At 1, 4, and 20 to 24 weeks postoperatively, vein segments were examined for patency and resected for histological evaluation. Statistical analysis was by Fisher's Exact test.

RESULTS

All vein segments were occluded at 1 and 4 weeks in all groups, despite histological evidence of progressive endothelial ingrowth. However, at 20 to 24 weeks, angiography demonstrated restoration of vessel patency in groups I (3/6) and II (3/5), but not in group III (0/6; P = .043), in which histology confirmed an obliterated lumen for all vessels.

CONCLUSION

An injectable, fibroblast-based, engineered construct prevents midterm to long-term recanalization in a leporine model of vascular sclerotherapy. This novel therapeutic approach may prevent recurrence of vascular malformations after sclerotherapy, thus reducing the need for repeated procedures and morbid operative resections.

Lymphatic Malformation of the Lingual Base and Oral Floor

BACKGROUND

Lymphatic malformation of the tongue and floor of the mouth is associated with chronic airway problems, recurrent infection, and functional issues related to speech, oral hygiene, and malocclusion. There are no accepted anatomic guidelines or treatment protocols.

METHODS

This retrospective review focused on anatomic extent, treatment, complications, and airway management in 31 patients with lymphatic malformation of the lingual base and oral floor.

RESULTS

Involved adjacent structures included the neck (77 percent), mandible (41 percent), face (42 percent), lips (10 percent), pharynx (45 percent), and larynx (26 percent). Fifty-eight percent of patients required tracheostomy during infancy; decannulation was possible in two-thirds of these patients. Management included resection alone (42 percent), resection and sclerotherapy (26 percent), resection and laser coagulation (16 percent), sclerotherapy and laser coagulation (16 percent), and resection and radiofrequency ablation (3 percent). Resection involved the neck (58 percent), floor of the mouth (52 percent), and tongue (42 percent); there were often multiple procedures. Aspiration was tried with little success in 10 percent of patients. Virtually all patients had residual abnormal lymphatic tissue. Complications and posttherapeutic problems included infection (81 percent), neural damage (27 percent), difficulty in speech (23 percent), feeding problems (10 percent), and seroma or hematoma (6 percent). Associated dental/orthognathic conditions, particularly prognathism and anterior open bite, were documented in one-third of patients.

CONCLUSIONS

The initial step in the protocol is control of the neonatal airway. Staged cervical resection is undertaken in late infancy to early childhood; resection should also include abnormal tissue in the oral floor. Sclerotherapy is primarily for macrocystic disease or secondarily for recurrent cysts following partial extirpation. Vesicles of the mucous membranes and dorsal tongue are treated either by sclerotherapy, laser (carbon dioxide, yttrium-aluminum-garnet, or potassium-titanyl-phosphate), or radiofrequency ablation. Reduction for macroglossia is indicated for persistent protrusion or to allow correction of malocclusion. Embolization controls lingual bleeding. Orthognathic procedures are undertaken at the appropriate age, only after lingual size and position are acceptable.

Kaposiform hemangioendothelioma without Kasabach-Merritt phenomenon

Kasabach-Merritt phenomenon is a serious coagulopathy associated with kaposiform hemangioendothelioma (KHE), tufted angioma, and possibly other vascular neoplasms. KHE presenting in the absence of Kasabach-Merritt phenomenon is rare, although tufted angioma frequently occurs without thrombocytopenia. We retrospectively reviewed 10 cases of KHE without Kasabach-Merritt phenomenon. The tumors appeared as soft tissue masses with the overlying skin being either normal, erythematous, or violaceous. There were no radiologic or microscopic differences in noncoagulopathic KHE as compared with coagulopathic KHE. Evidence of platelet trapping and hemosiderin deposition was seen histologically, despite normal serum platelet levels. All KHE were less than 8 cm in diameter, suggesting that tumors that grow no larger than this size are less likely to trap platelets in sufficient quantity to cause thrombocytopenia. Our series confirms that KHE appears with a wide spectrum of behavior and response to treatment. The decision as to whether or not to treat a noncoagulopathic KHE should be based on the size and location of the tumor and the possible side effects of therapy.

Auricular Arteriovenous Malformation: Evaluation, Management, and Outcome

BACKGROUND

The external ear is the second most common site for extracranial arteriovenous malformation in the head and neck.

METHODS

This retrospective review of 41 patients with auricular arteriovenous malformation was based on medical records, imaging studies, and photographs. Data were collected on natural history, progression, and outcome; patients were questioned about quality of life after treatment.

RESULTS

The median age at initial presentation was 26 years (range, 1 to 55 years), and Schobinger stage was I in two patients, II in 19 patients, and III in 20 patients. No patients had a Schobinger stage of IV. Expansion occurred during childhood in seven patients, adolescence in 14 patients, pregnancy in 10 patients, and adulthood in 10 patients. Distribution of auricular and extra-auricular arteriovenous malformation was not limited to "watershed" areas between vascular territories (angiosomes). Twelve patients were untreated (follow-up, 0.5 to 6 years). Mean follow-up time for the 29 treated patients was 5.19 years (range, 1 to 18.75 years). Proximal ligation in nine patients caused progression: eight of them underwent amputation and one had embolization. Fifteen patients had embolization only: the arteriovenous malformation worsened and amputation was necessary in six patients; in the remaining nine patients, two improved, four persisted, and three worsened. Of 20 patients who had auricular amputation, 16 (80 percent) were controlled, three (15 percent) improved, and one had unresectable, residual cervicofacial arteriovenous malformation. Of 22 of 29 treated patients surveyed, 81 percent were satisfied with their management. Hearing was either unaffected (n = 15) or diminished (n = 5); two patients noted decreased sound localization.

CONCLUSIONS

The authors recommend periodic evaluation for stage I to II auricular arteriovenous malformation and intervention if there is evolution to stage III. Preoperative embolization and partial or total amputation effectively control auricular and para-auricular arteriovenous malformation. Embolization can be palliative in children or in patients who are not psychologically prepared for amputation. Extensive extra-auricular arteriovenous malformation requires individualized endovascular therapy and resection.

Blue rubber bleb nevus syndrome: surgical eradication of gastrointestinal bleeding

OBJECTIVE

We report the largest clinical experience to date of surgically treated patients with blue rubber bleb nevus syndrome (BRBNS).

SUMMARY BACKGROUND DATA

BRBNS is a rare congenital disorder presenting with multifocal venous malformations of the skin, soft tissues, and gastrointestinal (GI) tract. Patients with BRBNS develop anemia from chronic GI bleeding, and require lifelong treatment with iron and blood transfusions. An aggressive surgical approach to treat the GI venous malformations of BRBNS has been considered unlikely to be successful because of the large number of lesions, their position throughout the GI tract, and the likelihood of recurrence. Based on our belief that eradicated lesions would not recur, we undertook the removal of all GI tract lesions in an effort to eliminate bleeding.

METHODS

Ten patients with BRBNS were treated from 1993 to 2002. Lesions were identified using complete GI endoscopy. The multiple venous malformations were removed by a combination of wedge resection, polypectomy, suture-ligation, segmental bowel resection, and band ligation.

RESULTS

Patient ages ranged from 2 to 36 years, and patients received an average of 53 prior blood transfusions. A mean of 137 focal GI venous malformations per patient were resected at operation (range 4-557), with a mean operative duration of 14 hours (range 7-23 hours). Only 1 patient who had a less extensive procedure developed recurrent GI bleeding. The mean follow-up period was 5.0 years (range 2.9-10.3 years).

CONCLUSIONS

We believe that an aggressive excisional approach is indicated for the venous anomalies that cause GI bleeding in BRBNS.

Enhancement of intravascular sclerotherapy by tissue engineering: short-term results

BACKGROUND/PURPOSE

Treatment of vascular malformations with sclerotherapy is often complicated by reexpansion secondary to endothelial recanalization. This study examined the use of an autologous fibroblast construct to enhance intraluminal scar formation after sclerotherapy.

METHODS

New Zealand rabbits (n = 15) underwent ethanol sclerotherapy of a segment of the facial vein. After intraluminal saline flush, animals were equally divided into 3 groups. In group I, no further manipulations were performed. In groups II and III, collagen hydrogel was injected into the sclerosed vein, respectively, without and seeded with autologous green fluorescent protein-labeled fibroblasts. One week postoperatively, the vein segments were examined for patency and resected for histology.

RESULTS

The sclerosed vein segments remained occluded in all animals. Histological examination of luminal thrombi demonstrated numerous viable fibroblasts in group III, whereas there were none in the control specimens from groups I and II. The presence of the injected autologous green fluorescent protein-labeled fibroblasts within thrombi of group III was confirmed by immunohistochemistry.

CONCLUSIONS

An injectable tissue-engineered construct enhances sclerotherapy of the jugular vein in a leporine model by reliably delivering fibroblasts that populate the resultant thrombus. Further analysis of this novel therapeutic concept as a means to augment permanent scar formation and reduce luminal recanalization is warranted.

Periorbital lymphatic malformation: clinical course and management in 42 patients

Lymphatic malformation in the orbital cavity and surrounding region often causes disfigurement and visual problems. To better clarify the evolution and treatment of this condition, the authors studied a retrospective cohort of 42 consecutive patients seen between 1971 and 2003 and analyzed anatomic features, complications, and management. The ratio of female to male patients was 1:1. Most periorbital lymphatic malformations were noted at birth (59 percent), presenting as either unilateral swelling (60 percent) or a periorbital mass (24 percent). Sixty-two percent of lesions were on the left side. The ipsilateral cheek, temple, and forehead also were involved in 57 percent of patients. Twenty-two percent of lesions were intraconal, 30 percent were extraconal, and 48 percent were in both spaces. Forty-five percent of children had an associated cerebral developmental venous anomaly. Periorbital lymphatic malformation caused major morbidity; 52 percent of patients had intralesional bleeding and 26 percent of patients had a history of infection. Other common complications included intermittent swelling (76 percent), blepharoptosis (52 percent), proptosis (45 percent), pain (21 percent), amblyopia (33 percent), chemosis (19 percent), astigmatism (17 percent), and strabismus (7 percent). Ultimately, 40 percent of children had diminished vision and 7 percent became blind in the affected eye. Management of periorbital lymphatic malformation involved an interdisciplinary team that included an interventional radiologist, a craniofacial surgeon, and an ophthalmologist. The two therapeutic strategies were sclerotherapy (40 percent) and resection (57 percent); most patients required several interventions. A coronal approach was used for subtotal excision of fronto-temporal-orbital lymphatic malformation in 13 patients, whereas a tarsal incision was used for lesions isolated to the eyelid (n = 14). Ocular proptosis was temporarily managed by tarsorrhaphy (n = 9), but expansion of the bony orbit was needed to correct persistent proptosis (n = 8). Orbital exenteration was necessary in two patients.

Infant sedation for MR imaging and CT: oral versus intravenous pentobarbital

PURPOSE

To compare the effectiveness and safety of oral (PO) versus intravenous (IV) pentobarbital sedation for magnetic resonance (MR) imaging and computed tomography (CT) in infants younger than 12 months.

MATERIALS AND METHODS

The institutional review board approved the review of medical records and determined informed consent to be unnecessary. All parents gave informed consent for patient sedation. Prior to MR imaging or CT, infants younger than 12 months were sedated with PO pentobarbital (4-8 mg per kilogram body weight) or IV pentobarbital (2-6 mg/kg), depending on the presence of an IV catheter or need for IV contrast medium. A computer database used to record sedation data was reviewed for data from January 1997 to September 2003. PO and IV sedation groups were compared for mean age, weight, dose, time to sedation, time to discharge, and duration of sedation with a two-sample Student t test. Multivariate analysis of covariance was used to determine whether differences in sedation time, time to discharge, and duration of sedation between groups were independent of age, weight, sex, American Society of Anesthesiologists physical status classification, dose, and type of procedure. Sedation effectiveness (outcome) was determined as the percentage of sedation failures in each group. Safety was determined separately for other adverse events as a total and for respiratory adverse events.

RESULTS

A total of 2164 infants received 2419 (1264 PO, 1155 IV) doses of pentobarbital for sedation. Weight and sex were comparable between groups. Time to sedation was significantly longer with PO than with IV pentobarbital (18 minutes +/- 11 vs 7 minutes +/- 7; P < .01), but time to discharge was similar, at approximately 108 minutes +/- 35. Total adverse events rate during sedation was not significantly different (0.8% [PO] vs 1.3% [IV]), but incidence of abnormal oxygen saturation (5% decrease from baseline, >1 minute duration) differed significantly (0.2% [PO] vs 0.9% [IV]; P = .02). Sedation effectiveness was comparable (failure rate, 0.5% [PO] vs 0.3% [IV]; P = .76).

CONCLUSION

PO pentobarbital has comparable effectiveness and a lower rate of respiratory complications compared with IV pentobarbital in infants younger than 12 months; its use should be considered, regardless of presence of an IV catheter.