Vascular malformations of the brain

Vein of Galen aneurysmal malformation: does size affect outcome?

PURPOSE

To validate a semiautomated method for segmenting vein of Galen aneurysmal malformations (VGAM) and to assess the relationship between VGAM volume and other angioarchitectural features, cardiological findings, and outcomes.

METHODS

In this retrospective study, we selected all subjects with VGAM admitted to the Gaslini Children's Hospital between 2009 and 2022. Clinical data were retrieved from electronic charts. We compared 3D-Slicer segmented VGAM volumes obtained by two independent observers using phase-contrast MR venography to those obtained with manual measurements performed on T2-weighted images. The relationship between VGAM volumes and clinical and neuroimaging features was then explored.

RESULTS

Forty-three subjects with VGAM (22 males, mean age 6.56 days) were included in the study. Manual and semiautomated VGAM volumes were well correlated for both readers (r = 0.86 and 0.82, respectively). Regarding reproducibility, the inter-rater interclass correlation coefficients were 0.885 for the manual method and 0.992 for the semiautomated method (p < 0.001). The standard error for repeated measures was lower for the semiautomated method (0.04 versus 0.40 of manual method). Higher VGAM volume was associated with superior sagittal sinus narrowing, jugular bulb stenosis, and aqueductal stenosis (p < 0.05). A weak correlation was found between VGAM volume and straight sinus dilatation (r = 0.331) and superior sagittal sinus index (r =  - 0.325). No significant associations were found with cardiac findings, post-embolization complications, and outcome (p > 0.05).

CONCLUSIONS

Semiautomated VGAM volumetry is feasible and reliable with improved reproducibility compared to the manual method. VGAM volume is not a prognostic factor for clinical outcome, but it is related to other venous findings with potential hemodynamic effects.

That which is unseen: 3D printing for pediatric cerebrovascular education

INTRODUCTION

Pediatric cerebrovascular lesions are very rare and include aneurysms, arteriovenous malformations (AVM), and vein of Galen malformations (VOGM).

OBJECTIVE

To describe and disseminate a validated, reproducible set of 3D models for optimization of neurosurgical training with respect to pediatric cerebrovascular diseases METHODS: All pediatric cerebrovascular lesions treated at our institution with adequate imaging studies during the study period 2015-2020 were reviewed by the study team. Three major diagnostic groups were identified: aneurysm, AVM, and VOGM. For each group, a case deemed highly illustrative of the core diagnostic and therapeutic principles was selected by the lead and senior investigators for printing (CSG/JM). Files for model reproduction and free distribution were prepared for inclusion as Supplemental Materials.

RESULTS

Representative cases included a 7-month-old female with a giant left MCA aneurysm; a 3-day-old male with a large, complex, high-flow, choroidal-type VOGM, supplied from bilateral thalamic, choroidal, and pericallosal perforators, with drainage into a large prosencephalic vein; and a 7-year-old male with a left frontal AVM with one feeding arterial vessel from the anterior cerebral artery and one single draining vein into the superior sagittal sinus CONCLUSION: Pediatric cerebrovascular lesions are representative of rare but important neurosurgical diseases that require creative approaches for training optimization. As these lesions are quite rare, 3D-printed models and open source educational materials may provide a meaningful avenue for impactful clinical teaching with respect to a wide swath of uncommon or unusual neurosurgical diseases.

Neonatal giant dural sinus ectasia: a multimodality imaging approach

Dural venous sinus ectasia is a rare anomaly characterised by the formation of a large vascular lake within the leaves of the dural sinuses, usually associated with thrombosis. These lesions can cause brain compression, cardiac insufficiency and disseminated intravascular coagulation, which may lead to poor prognosis. We present the case of a neonate who presented with an intracranial mass on prenatal ultrasound. Postnatal transcranial ultrasonography, cranial CT and cranial MRI demonstrated a large lesion predominantly occupying the dural sinus confluence, extending into the sagittal sinus, straight sinus and right transverse sinus. The left marginal sinus remains unfused and patent. Concomitant arteriovenous malformations were evident in the median interhemispheric fissure and the left Sylvian fissure. There are several published case reports and case series describing malformations of the dural sinuses in perinatal and neonatal patients in recent years, but this case is unique in that: (1) there is the presence of a vascular malformation concomitant to the dural sinus ectasia and (2) it highlights the importance of imaging in clinching the diagnosis of giant dural venous sinus ectasia, as it is often misdiagnosed as more common conditions such as extra-axial intracranial haemorrhage.

Congenital Retinal Macrovessel and the Association of Retinal Venous Malformations With Venous Malformations of the Brain

Importance

Congenital retinal macrovessel (CRM) is a rarely reported venous malformation of the retina that is associated with venous anomalies of the brain.

Objective

To study the multimodal imaging findings of a series of eyes with congenital retinal macrovessel and describe the systemic associations.

Design, Setting, and Participants

In this cross-sectional multicenter study, medical records were retrospectively reviewed from 7 different retina clinics worldwide over a 10-year period (2007-2017). Patients with CRM, defined as an abnormal, large, macular vessel with a vascular distribution above and below the horizontal raphe, were identified. Data were analyzed from December 2016 to August 2017.

Main Outcomes and Measures

Clinical information and multimodal retinal imaging findings were collected and studied. Pertinent systemic information, including brain magnetic resonance imaging findings, was also noted if available.

Results

Of the 49 included patients, 32 (65%) were female, and the mean (SD) age at onset was 44.0 (20.9) years. A total of 49 eyes from 49 patients were studied. Macrovessel was unilateral in all patients. Color fundus photography illustrated a large aberrant dilated and tortuous retinal vein in all patients. Early-phase frames of fluorescein angiography further confirmed the venous nature of the macrovessel in 40 of 40 eyes. Optical coherence tomography angiography, available in 17 eyes (35%), displayed microvascular capillary abnormalities around the CRM, which were more evident in the deep capillary plexus. Of the 49 patients with CRM, 39 (80%) did not illustrate any evidence of ophthalmic complications. Ten patients (20%) presented with retinal complications, typically an incidental association with CRM. Twelve patients (24%) were noted to have venous malformations of the brain with associated magnetic resonance imaging. Of these, location of the venous anomaly in the brain was ipsilateral to the CRM in 10 patients (83%) and contralateral in 2 patients (17%), mainly located in the frontal lobe in 9 patients (75%).

Conclusions and Relevance

Our study has identified an association between macrovessels in the retina and venous anomalies of the brain (24% compared with 0.2% to 6.0% in the normal population). Thus, we recommend new guidelines for the systemic workup of patients with CRM to include brain magnetic resonance imaging with contrast. These lesions may be more accurately referred to as retinal venous malformations, which may raise awareness regarding potential cerebral associations.

Hemodynamics Associated With Intracerebral Arteriovenous Malformations: The Effects of Treatment Modalities

The understanding of the physiology of cerebral arteriovenous malformations (AVMs) continues to expand. Knowledge of the hemodynamics of blood flow associated with AVMs is also progressing as imaging and treatment modalities advance. The authors present a comprehensive literature review that reveals the physical hemodynamics of AVMs, and the effect that various treatment modalities have on AVM hemodynamics and the surrounding cortex and vasculature. The authors discuss feeding arteries, flow through the nidus, venous outflow, and the relative effects of radiosurgical monotherapy, endovascular embolization alone, and combined microsurgical treatments. The hemodynamics associated with intracranial AVMs is complex and likely changes over time with changes in the physical morphology and angioarchitecture of the lesions. Hemodynamic change may be even more of a factor as it pertains to the vast array of single and multimodal treatment options available. An understanding of AVM hemodynamics associated with differing treatment modalities can affect treatment strategies and should be considered for optimal clinical outcomes.

Effective Surgical Management of Competitive Venous Outflow Restriction After Radiosurgery for Cerebral AVMs: Report of 2 Cases

BACKGROUND

Intracranial arteriovenous malformations (AVMs) are complex pathologies. For patients who do not present with hemorrhage, treatment strategies are often predicated on reducing the risk of hemorrhage and minimizing morbidity. Outcomes vary according to the efficacy of treatment selected. Radiosurgical treatment of certain AVMs can result in incomplete obliteration and may also have only a minimal effect on the presenting nonhemorrhagic symptoms.

CASE DESCRIPTIONS

We present 2 cases of patients with AVMs who were initially treated with radiosurgery. Both patients' primary clinical symptoms were headaches, which persisted after radiosurgical treatment but abated after subsequent microsurgical resection with or without endovascular embolization.

CONCLUSION

Venous outflow obstruction is likely a sizable contributive factor in occipital AVMs among patients who present with headaches and symptoms of intracranial hypertension. Because these high-flow lesions may be suboptimally responsive to stereotactic radiosurgery, microsurgical resection, with or without adjunctive endovascular embolization, should be considered as an initial and definitive treatment strategy. Optimal outcomes may be achieved in patients with a visual deficit that is anatomically correlated to their AVMs.

Management of midline dural sinus malformations and review of the literature

PURPOSE

Dural sinus malformations (DSMs) are rare pediatric vascular lesions that have variable presentations and outcomes. We present three cases of midline DSMs and discuss the treatment strategy employed for each lesion. A review of the literature was completed to summarize current literature and treatment practices.

METHODS

A retrospective review of the electronic medical record and all available imaging studies was performed for each of our patients.

RESULTS

Patient 1 had a prenatally diagnosed DSM which decreased in size despite no intervention. She was born without complication and continues to do well at 15 months of age. Patient 2 presented 2 weeks after birth with cardiac failure, intracranial hemorrhage, and seizures and imaging showed a large midline DSM with multiple high-flow shunts. She required multiple endovascular embolizations with complete occlusion of the lesion. At her 3-year follow-up, she was neurologically normal. The third patient was diagnosed prenatally with an enlarging DSM. Multiple endovascular embolizations, surgical decompression, cranial expansion, and CSF diversion were required for treatment. At her 2.5-year follow-up, she was meeting developmental milestones, with some motor delay.

CONCLUSION

Early diagnosis and treatment, if necessary, of DSMs are critical to prevent cardiac failure or parenchymal injury from chronic venous hypertension. Management should be decided on individual case basis depending on the angioarchitecture and progression of the lesion and can involve observation, endovascular embolization, surgical interventions, or a combination of treatments. A personalized approach to treating these variable lesions can be associated with good outcomes.

Vascular Disorders of the Cerebellum in Children

Key differences exist in the epidemiology, pathophysiology, and clinical presentation of vascular lesions of the cerebellum in children versus adults. An understanding of these differences and an appreciation of the distinct imaging features of these lesions aid in distinguishing normal vascular variations from pathology, in predicting lesion etiology, and in directing effective treatment strategies. This paper reviews the embryogenesis of the normal vascular system of the cerebellum and brainstem and then discusses the clinical and imaging features of the common vascular lesions affecting these structures in the pediatric population.

Intraoperative Ultrasonography Combined with Indocyanine Green Video-Angiography in Patients with Cerebral Arteriovenous Malformations

BACKGROUND AND PURPOSE

During the operation, accurately identifying the boundary of cerebral arteriovenous malformation (AVM) and discriminating between feeding arteries and draining veins is the key to successful surgical treatment of cerebral AVM. We evaluated the application of intraoperative ultrasonography (IOU) combined with intraoperative indocyanine green video-angiography (IOICGA) in the patients with cerebral AVM.

METHODS

The effects of IOU combined with IOICGA on AVM surgery were observed in 12 patients with cerebral AVM.

RESULTS

The lesions of cerebral AVM were completely removed in the 12 patients. IOU could clearly visualize the boundary of AVM, so no patients had massive hemorrhage caused by rupture of malformed vessels. IOU also could detect the location of deep vessels and a total of 11 deep vessels were identified in the 12 patients. IOICGA was performed 41 times altogether in the 12 patients, and 31 feeding arteries and 10 draining veins were identified, so there was no massive hemorrhage caused by misjudgment of feeding arteries or draining veins.

CONCLUSIONS

IOU combined with IOICGA can identify the boundary of AVM, detect deep vessels, and discriminate between feeding arteries and draining veins, reducing operation difficulty, decreasing mortality and disability rate, and increasing the rate of complete excision.