Paediatric and adult vascular intracranial complications of sickle-cell disease

Preventive treatment of unruptured intracranial aneurysms in adult patients with sickle cell anemia: A cohort study

BACKGROUND AND PURPOSE

Intracranial aneurysms are frequent in patients with sickle cell anemia, while subarachnoid hemorrhage is a major cause of death and disability in young adult patients. Several characteristics, such as younger age and smaller size at rupture, may incline therapeutic decision towards exclusion treatments. Clinical guidelines on treatment of unruptured intracranial aneurysms in this population are still missing. We aimed to assess the safety and efficacy of the treatment of unruptured intracranial aneurysm in patients with sickle cell anemia, using an adapted hematological preparation regimen.

PATIENTS AND METHODS

Adult patients with sickle cell anemia and treated unruptured aneurysms by endovascular therapy or neurosurgery were included in this retrospective cohort study. Treatment decision was reached after multi-disciplinary assessment. A pre-operative blood transfusion protocol was undertaken targeting a HbS below 30%. Demographic data, hematological preparation parameters and clinical and radiological outcomes were documented.

RESULTS AND CONCLUSIONS

Twenty-five procedures were performed in 18 patients encompassing 19 aneurysms treated by embolization and 6 by surgery. Median age at treatment was 34 years-old and median aneurysm dome size was 4.4 mm. Immediate aneurysm exclusion rate was 85.7% after endovascular therapy and 100% after neurosurgery. Median follow-up was 6 months, with all patients being asymptomatic at last follow-up. Two transitory ischemic neurological deficits, as well as four cases of iodine-induced encephalopathy were identified after embolization. No complication occurred after surgery. Endovascular therapy by coiling and neurosurgical treatment of unruptured intracranial aneurysms appears to be safe in patients with sickle cell anemia and should be considered given the specific hemorrhagic risk observed in this population. A rigorous hematological preparation, associated with a dedicated peri‑operative protocol and an adequate therapeutic strategy are essential prerequisites.

Intracranial Aneurysms in Sickle Cell Disease

Background:

The exact causes of intracranial aneurysms (IAs) are still unknown. However, certain diseases are known to be associated with IAs.

Objective:

To analyze the differences in IA characteristics in the general population and in individuals with sickle-cell disease (SCD).

Methods:

We systematically searched PubMed, Scopus, Web of Science, and Cochrane Library for Data on SCD patients with IAs. We compared IA characteristics of SCD patients with those from 2451 healthy IA carriers from our observational cohort.

Results:

129 SCD patients with IAs were identified in 42 studies. The SCD patient cohort was characterized by younger age (mean 27.1 vs 54.9 years, p<0.0001) and lower female prevalence (57.7% vs 68.4%, p=0.0177). The prevalence (47% vs 34.5%, p=0.004) and the number (3.02 vs 2.56 IAs/patient, p=0.004) of multiple IAs were also higher in the SCD cohort. Unruptured IAs (3.27 vs 6.16 mm, p<0.0001), but not ruptured IAs (7.8 vs 7.34 mm, p=0.9086) were significantly smaller in the SCD cohort. In addition, IAs were more frequently located in the internal carotid artery (45% vs 29%, p<0.0001) or posterior circulation (43% vs 20%, p<0.0001). Higher age (≥30 years, p=0.007), IA size ≥7 mm (p=0.008), and location in posterior circulation (p=0.01) were independently associated with subarachnoid hemorrhage in SCD.

Conclusion:

There is a distinct demographic and radiographic pattern of IA in SCD. Risk factors for IA rupture in SCD are mostly congruent with those in healthy individuals.

Use of a flow-diverting stent for ruptured dissecting aneurysm treatment in a patient with sickle cell disease

INTRODUCTION

Sickle cell disease (SCD) is a clinical phenotype that presents a unique challenge to the interventionalist, particularly when stent therapy is contemplated. Homozygous individuals are likely at increased risk for thromboembolic complications. There are no formal guidelines regarding antiplatelet therapy in the short or long term for intracranial stent use in SCD. The authors describe the novel use of a pipeline embolization device (PED) to treat a ruptured dissecting bilobed/fusiform vertebral artery V4 aneurysm in an SCD patient complicated by tortuous proximal anatomy and the anterior spinal artery arising from the diseased segment. Considerations regarding antiplatelet therapy in this scenario are discussed.

CASE REPORT

A 50-year-old woman with homozygous recessive SCD was transported to the emergency department and presented with diffuse subarachnoid hemorrhage. CT angiography demonstrated a left-sided 3 × 5 mm fusiform bi-lobulated presumed dissecting vertebral artery aneurysm, immediately distal to the origin of the posterior inferior cerebellar artery (PICA). A PED was deployed within the V4 segment across the aneurysm. Post-treatment angiography showed patency of the parent artery, and patency of the "jailed" anterior spinal artery and of the PICA.

DISCUSSION

Selecting a treatment method in SCD patients with a ruptured intracranial aneurysm is challenging and there are no clinical trials comparing treatment methods in this population. The authors demonstrate that flow diversion is feasible in SCD, which has not been described in the literature. Additionally, the case stresses the peri- and post-procedural management of SCD, as well as long-term considerations with a flow-diverting stent in place.

A review of spontaneous intracranial extradural hematoma in sickle-cell disease

Sickle-cell disease is common among patients of Afro-Caribbean origin. Though it can precipitate neurological conditions, it only rarely causes neurosurgical problems, with very few reported cases. We describe the case of a 7-year-old girl with a background of sickle-cell disease (SCD) brought into an acute neurosurgical unit in extremis, signs of a raised ICP, and with no history of recent trauma. Following further investigations, an acute drop in the hemoglobin and hematocrit levels were noted, with the cause of her presentation being attributed to a sickling crisis causing skull convexity infarction and resulting in spontaneous bilateral extradural hematomas requiring emergency evacuation. We review the current literature and propose the pathophysiological mechanism behind this phenomenon.

Treatment of a cerebral pial arteriovenous fistula in a patient with sickle cell disease-related moyamoya syndrome: case report

Sickle cell disease (SCD) is an autosomal recessive hematological disorder, characterized by sickling of the red blood cells in response to a hypoxic stress and vaso-occlusive crises. It is associated with moyamoya-like changes on cerebral angiographic imaging in 43% of patients. Cerebral aneurysms, arteriovenous malformations, and dural arteriovenous fistulas (AVFs) have been described in association with SCD and moyamoya disease. However, the description of a pial AVF (pAVF) in a patient with SCD and/or moyamoya formation has not yet been reported. The authors present the case of a 15-year-old boy with SCD-associated moyamoya disease harboring a pAVF who developed a de novo venous aneurysm 8 months after undergoing indirect superficial temporal artery-middle cerebral artery (MCA) bypass that was complicated by bilateral ischemia of the MCA territory. The pAVF was successfully treated with transarterial embolization using Onyx. The authors describe the possible pathophysiological mechanisms and management strategies for this rare occurrence.

Unruptured Intracranial Aneurysms in Children With Sickle Cell Disease

BACKGROUND:

Intracranial aneurysms (IAs) are rare in the general pediatric population and account for &lt;2% of all cerebral aneurysms. Only 7 children with sickle hemoglobinopathy and IAs have been reported, the majority of which were discovered after rupture.

OBJECTIVE:

To report the prevalence of unruptured IAs in a selected population of children with sickle cell disease (SCD) and to describe the aneurysm morphology, hematologic characteristics, and management in this patient population.

METHODS:

A retrospective review of the electronic database for all children with SCD who underwent brain magnetic resonance imaging or angiography from January 2002 to August 2013 at a single institution was performed. Records were reviewed for IA, age, sex, sickle cell genotype, neurological symptoms, hematologic indexes, transcranial Doppler findings, and management.

RESULTS:

Five of 179 children (2.8%) with SCD imaged by brain magnetic resonance imaging or angiography were diagnosed with IAs. None presented with subarachnoid hemorrhage. Four patients (80%) had HbSS disease, and 1 patient had hemoglobin sickle cell HbSC disease. A total of 18 aneurysms were detected; the majority of patients had multiple aneurysms (80%) and bilateral involvement (60%).

CONCLUSION:

Children with SCD are at risk for developing multiple intracranial aneurysms, and a high index of suspicion must be maintained during the interpretation of routine magnetic resonance imaging or angiography of the brain.

Angiogenesis in steno-occlusive vasculopathies as a common pathway for intracranial haemorrhage. A report of six cases

Vasculopathies, including vasculitis of the central nervous system, can lead to stenosed, cicatrized vessels and the development of arterio-arteriolar collateral vessels. Bleeding due to these vascular changes, although rare, does occur. We describe six patients (all female, age range, 21-52 years; mean age, 42 years) with steno-occlusive lesions of intracranial vessels who presented with an acute intracranial haemorrhage. All had arterial steno-occlusive changes in conjunction with extensive leptomeningeal and arterio-arteriolar collaterals. Within the collaterals, focal dilatations could be identified, which were in close spatial relationship with the intracranial haemorrhage. Cause of bleeding was depicted on CT angiography in four out of six patients. One patient presented in childhood with acute stroke, one patient was diagnosed with Buerger's disease and one with sickle cell disease; the other three patients had no relevant history and the exact cause remained unclear. Outcome was favourable in all patients. Despite focal vascular weaknesses, no recurrent haemorrhage was seen during follow-up, supporting, at least in this small patient group, a conservative wait-and-see policy.