Cranial subarachnoid and subdural haemorrhage caused by spinal melanoma metastasis

Vascular complications in patients with brain tumors

PURPOSE OF REVIEW

Venous thromboembolism (VTE) and other vascular events are common in patients with brain tumors, but their optimal management is not firmly established, in large part due to the competing risk of intracranial hemorrhage (ICH) in this population.

RECENT FINDINGS

There is conflicting evidence on whether therapeutic anticoagulation increases the risk of ICH in patients with brain tumors, with several metanalysis and retrospective cohort studies showing an increased risk and others showing no differences. Current guidelines recommend anticoagulating brain tumors patients with VTE with either low-molecular weight heparin (LMWH) or direct oral anticoagulants (DOACs), and several retrospective studies have shown the risk of ICH with DOACs is similar or smaller than with LMWH.

SUMMARY

An increased risk of VTE exists in a variety of brain tumor types. Most patients with brain tumors and VTE should receive therapeutic anticoagulation, and recent retrospective evidence supports the use of both LMWH and DOACs as effective and relatively safe in this setting. Patients with brain tumors are also at increased risk of other vascular tumor- or treatment-related complications whose optimal management is unclear.

OTO-Net: An Automated MRA Image Segmentation Network for Intracranial Aneurysms

Intracranial aneurysms are local dilations of the cerebral blood vessels; people with intracranial aneurysms have a high risk to cause bleeding in the brain, which is related to high mortality and morbidity rates. Accurate detection and segmentation of intracranial aneurysms from Magnetic Resonance Angiography (MRA) images are essential in the clinical routine. Manual annotations used to assess the intracranial aneurysms on MRA images are substantial interobserver variability for both aneurysm detection and assessment of aneurysm size and growth. Many prior automated segmentation works have focused their efforts on tackling the problem, but there is still room for performance improvement due to the significant variability of lesions in the location, size, structure, and morphological appearance. To address these challenges, we propose a novel One-Two-One Fully Convolutional Networks (OTO-Net) for intracranial aneurysms automated segmentation in MRA images. The OTO-Net uses full convolution to achieve intracranial aneurysms automated segmentation through the combination of downsampling, upsampling, and skip connection. In addition, loss ensemble is used as the objective function to steadily improve the backpropagation efficiency of the network structure during the training process. We evaluated the proposed OTO-Net on one public benchmark dataset and one private dataset. Our proposed model can achieve the automated segmentation accuracy with 98.37% and 97.86%, average surface distances with 1.081 and 0.753, dice similarity coefficients with 0.9721 and 0.9813, and Hausdorff distance with 0.578 and 0.642 on these two datasets, respectively.

Intracranial subarachnoid hemorrhage resulting from non-cervical spinal arteriovenous lesions: Analysis of possible cause of bleeding and literature review

Subarachnoid hemorrhage (SAH) or intraventricle hemorrhage (IVH) with negative cerebral digital subtraction angiography (DSA) results, which are due to non-cervical spinal arteriovenous lesions, are uncommon. In this article we presented three cases from our hospital and nineteen cases from prior published literature and discussed clinical features, possible mechanisms underlying the hemorrhage and therapeutic strategies for managing this unusual entity. Our analysis revealed that headache was the most common initial symptom. Almost 60% of patients had symptoms related to the spinal cord at admission. Intramedullary arteriovenous malformations (AVM) were the most common type of malformation, and the thoracic segment was the most common location of the non-cervical spinal arteriovenous lesions. More than half of the patients had additional aneurysms. Surgery was chosen as the primary treatment modality in this series. Therefore, we speculate that thoracolumbar spinal arteriovenous lesions are an unusual cause of intracranial SAH with negative cerebral DSA results. If non-cervical spinal AVMs were associated with DSA-negative SAH, the pattern of hemorrhage could be manifested as the blood in supratentorial cisterns, the fourth ventricle or no copious blood around the foramen magnum as well (somewhat paradoxically), it depends on the timing of detection and image evaluation. The formation and the rupture of associated aneurysms were the most likely immediate cause of the intracranial SAH. If non-cervical spinal AVMs were not associated with DSA-negative SAH and all cases were genuine cases of 'SAH-of-unknown origin', the spinal AVM could be considered as incidental finding. Magnetic resonance imaging (MRI) of the complete spinal neuraxis is recommended to either exclude or identify a spinal lesion in these patients. Catheter-based spinal angiography remains the gold standard for the diagnosis of spinal vascular diseases. The decision regarding a therapeutic strategy is based on the angioarchitecture and on the type of spinal arteriovenous lesions.