Brain arteriovenous malformation multiplicity predicts the diagnosis of hereditary hemorrhagic telangiectasia: quantitative assessment

Cerebral vascular malformations in hereditary hemorrhagic telangiectasia

Object

Hereditary hemorrhagic telangiectasia (HHT) is a hereditary disorder characterized by mucocutaneous telangiectasias, frequent nosebleeds, and visceral arteriovenous malformations (AVMs). Few reports have outlined the prevalence of the various cerebral vascular malformations found in patients with HHT. The authors set out to define the prevalence of cerebral vascular malformations in a population of HHT patients who underwent imaging with 3-T imaging (MRI/MR angiography [MRA]) of the brain.

Methods

A retrospective review of prospectively collected data was carried out using a database of 372 HHT patients who were seen and examined at the Georgia Regents University HHT Center and screened with 3-T MRI/MRA. Data were tabulated for numbers and types of vascular malformations in this population.

Results

Arteriovenous malformations were identified in 7.7%, developmental venous anomalies in 4.3%, and cerebral aneurysms in 2.4% of HHT patients. The HHT AVMs tended to be supratentorial, small, and cortical in this series, findings consistent with other recent studies in the literature. An arteriovenous fistula, cavernous malformation, and capillary telangiectasia were identified in 0.5%, 1%, and 1.9% of HHT patients, respectively.

Conclusions

Few studies have investigated the prevalence of the various vascular malformations found in HHT patients screened with 3-T MRI/MRA of the brain. Hereditary hemorrhagic telangiectasia AVMs are more likely to be multiple and have a tendency toward small size and cortical location. As such, they are often treated using a single-modality therapy.

Brain arteriovenous malformations in patients with hereditary hemorrhagic telangiectasia: clinical presentation and anatomical distribution

BACKGROUND

Hereditary hemorrhagic telangiectasia is an autosomal dominant genetic disease with a wide array of vascular malformations involving multiple organs. Brain arteriovenous malformations can lead to intracranial hemorrhage and are often diagnosed only after patients become symptomatic. Early diagnosis and interventional treatment may prevent neurologic sequelae or death. Because of the rarity of defined cases, the spectrum of presentations in children with brain arteriovenous malformations and hereditary hemorrhagic telangiectasia has not been explored in detail. Here, we report our experience in children with hereditary hemorrhagic telangiectasia and brain arteriovenous malformations regarding both disease manifestations at presentation and the spectrum of brain arteriovenous malformation manifestations.

METHODS

A retrospective review of demographics, clinical manifestations, and brain magnetic resonance imaging/computed tomography scan findings in 115 patients with confirmed hereditary hemorrhagic telangiectasia (HHT) was conducted using the Hospital for Sick Children's HHT Clinic database for the years 1997-2012.

RESULTS

Eleven patients (four girls and seven boys) were diagnosed with hereditary hemorrhagic telangiectasia and brain arteriovenous malformations during this period. Five patients initially presented with epistaxis, four presented with intracranial hemorrhage, and two were asymptomatic with a positive family history of confirmed hereditary hemorrhagic telangiectasia. Although all children had an index case with hereditary hemorrhagic telangiectasia in the family, in three patients, hereditary hemorrhagic telangiectasia was not diagnosed before the child's presentation with intracranial hemorrhage. Multiple brain arteriovenous malformations were found in five patients, with one patient having bithalamic arteriovenous malformations.

CONCLUSIONS

This study highlights the importance of both family history and early clinical signs to prompt further diagnostic testing to avoid intracranial hemorrhage from brain arteriovenous malformations in children with hereditary hemorrhagic telangiectasia.

Imaging Biomarkers for Intra-arterial Stroke Therapy

Despite high rates of early revascularization with intra-arterial stroke therapy, the clinical efficacy of this approach has not been clearly demonstrated. Neuroimaging biomarkers will be useful in future trials for patient selection and for outcomes evaluation. To identify patients who are likely to benefit from intra-arterial therapy, the combination of vessel imaging, infarct size quantification and degree of neurologic deficit appears critical. Perfusion imaging may be useful in specific circumstances, but requires further validation. For measuring treatment outcomes, surrogate biomarkers that appear suitable are angiographic reperfusion as measured by the modified Thrombolysis in Cerebral Infarction scale and final infarct volume.

Pediatric intracranial arteriovenous shunts: a global overview

INTRODUCTION

Cerebral arteriovenous shunts (CAVS) in the pediatric population cannot be compared to those in adults as they present different anatomical, physiological, and pathological characteristics concerning the arterial and venous vasculature and the cerebrospinal fluid physiology. These lesions develop in a maturing brain, of which expression is difficult to assess, with a potential for recovery different from that in adults.

DISCUSSION

Their impact on the brain will be different in the antenatal period, in neonates, in infants, and in children, with variable symptoms according to each age group. We review different classifications of pediatric CAVS (according to the anatomical space in which they develop, their type and architecture, and the age at which they reveal), describe their evolution, and discuss the current role of endovascular treatment in the management of these vascular lesions.

The use of US health insurance data for surveillance of rare disorders: hereditary hemorrhagic telangiectasia

PURPOSE

To assess the utility of US health insurance data for surveillance of hereditary hemorrhagic telangiectasia, an autosomal-dominant blood vasculature disorder with an estimated prevalence of 1.5-2.0 per 10,000 persons worldwide.

METHODS

We used 2005-2010 MarketScan Research Databases to identify individuals with employer-sponsored health insurance and International Classification of Disease, 9th Revision, Clinical Modification codes of 448.0 present in either one inpatient claim or two outpatient claims 30 days apart to define hereditary hemorrhagic telangiectasia. We examined frequencies of International Classification of Disease, 9th Revision, Clinical Modification codes for conditions that are complications of hereditary hemorrhagic telangiectasia among individuals with hereditary hemorrhagic telangiectasia and the general population to identify combinations of codes associated with hereditary hemorrhagic telangiectasia.

RESULTS

Excluding observations from one state, the average prevalence of hereditary hemorrhagic telangiectasia was 0.3 per 10,000 persons. The reported prevalence rose with age from ~0.1 per 10,000 at ages <30 years to 1.0-1.1 per 10,000 at ages 70 years and above. The condition codes that were most specific to presumed hereditary hemorrhagic telangiectasia were lung arteriovenous malformations and upper gastrointestinal angiodysplasia. Combinations of those codes and codes for brain arteriovenous malformation and epistaxis were highly predictive of reporting of hereditary hemorrhagic telangiectasia, with 20-57% of enrollees with those codes also meeting the study definition for hereditary hemorrhagic telangiectasia.

CONCLUSION

Hereditary hemorrhagic telangiectasia is underrecognized in US administrative data. Administrative health data can be used to identify individuals with combinations of signs that are suggestive of hereditary hemorrhagic telangiectasia. Studies are needed to test the hypothesis that referral for evaluation of individuals with administrative records suggestive of undiagnosed hereditary hemorrhagic telangiectasia could lead to diagnosis and access to life-saving treatments for both them and affected family members.

Brain Vascular Malformation Consortium: Overview, Progress and Future Directions

Brain vascular malformations are resource-intensive to manage effectively, are associated with serious neurological morbidity, lack specific medical therapies, and have no validated biomarkers for disease severity and progression. Investigators have tended to work in "research silos" with suboptimal cross-communication. We present here a paradigm for interdisciplinary collaboration to facilitate rare disease research. The Brain Vascular Malformation Consortium (BVMC) is a multidisciplinary, inter-institutional group of investigators, one of 17 consortia in the Office of Rare Disease Research Rare Disease Clinical Research Network (RDCRN). The diseases under study are: familial Cerebral Cavernous Malformations type 1, common Hispanic mutation (CCM1-CHM); Sturge-Weber Syndrome (SWS); and brain arteriovenous malformation in hereditary hemorrhagic telangiectasia (HHT). Each project is developing biomarkers for disease progression and severity, and has established scalable, relational databases for observational and longitudinal studies that are stored centrally by the RDCRN Data Management and Coordinating Center. Patient Support Organizations (PSOs) are a key RDCRN component in the recruitment and support of participants. The BVMC PSOs include Angioma Alliance, Sturge Weber Foundation, and HHT Foundation International. Our networks of clinical centers of excellence in SWS and HHT, as well as our PSOs, have enhanced BVMC patient recruitment. The BVMC provides unique and valuable resources to the clinical neurovascular community, and recently reported findings are reviewed. Future planned studies will apply successful approaches and insights across the three projects to leverage the combined resources of the BVMC and RDCRN in advancing new biomarkers and treatment strategies for patients with vascular malformations.

Brain arteriovenous malformations associated with hereditary hemorrhagic telangiectasia: gene-phenotype correlations

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant genetic disease with a wide spectrum of vascular malformations (VMs) involving multiple organs. Nine to 16% of patients with HHT harbor brain arteriovenous malformations (AVMs), which can cause intracranial hemorrhage (ICH). Our objective was to study clinical manifestations of brain AVMs in patients with HHT and correlate these with the specific gene mutated. We reviewed records of 171 patients with HHT and brain AVMs. A history of ICH was found in 27% (41/152) patients, with a mean age of 26 ± 18 range, (0-68) years. All of patients with ICH were neurologically asymptomatic prior to ICH. Multiple brain AVMs were found in 23% (170/39) of patients on initial examination. Genetic test results were available in 109 (64%) patients. Mutations in ENG, ACVRL1, and SMAD4 were present in 75 (69%), 18 (17%), and 2 (2%), respectively. A history of ICH was reported in 24% of patients with an ENG mutation and 27% of patients with an ACVRL1 mutation, with a mean age of 26 ± 16 (range, 2-50) and 18 ± 21 (0-48) years, respectively. No statistically significant differences in age at first brain AVM diagnosis, prevalence of ICH history, age at ICH, or other manifestations of brain AVMs were observed among gene groups. In conclusion, no evidence for differences in brain AVM characteristics was observed among HHT gene groups, although we cannot exclude clinically important differences. Larger studies are needed to further guide brain AVM screening decisions in patients with HHT.