Abstract

BACKGROUND Artificial intelligence (AI)-driven software has been developed and become commercially available within the past few years for the detection of intracranial hemorrhage (ICH) and chronic cerebral microbleeds (CMBs). However, there is currently no systematic review that summarizes all of these tools or provides pooled estimates of their performance. METHODS In this PROSPERO-registered, PRISMA compliant systematic review, we sought to compile and review all MEDLINE and EMBASE published studies that have developed and/or tested AI algorithms for ICH detection on non-contrast CT scans (NCCTs) or MRI scans and CMBs detection on MRI scans. RESULTS In total, 40 studies described AI algorithms for ICH detection in NCCTs/MRIs and 19 for CMBs detection in MRIs. The overall sensitivity, specificity, and accuracy were 92.06%, 93.54%, and 93.46%, respectively, for ICH detection and 91.6%, 93.9%, and 92.7% for CMBs detection. Some of the challenges encountered in the development of these algorithms include the laborious work of creating large, labeled and balanced datasets, the volumetric nature of the imaging examinations, the fine tuning of the algorithms, and the reduction in false positives. CONCLUSIONS Numerous AI-driven software tools have been developed over the last decade. On average, they are characterized by high performance and expert-level accuracy for the diagnosis of ICH and CMBs. As a result, implementing these tools in clinical practice may improve workflow and act as a failsafe for the detection of such lesions. REGISTRATION-URL: https://www.crd.york.ac.uk/prospero/ Unique Identifier: CRD42021246848.

Abstract

OBJECTIVE Spinal subdural hematoma (S-SDH) rarely occurs after aneurysmal subarachnoid hemorrhage (SAH). Little information is known regarding the management and prognosis of patients with both S-SDH and SAH. Here, we present an illustrative Case and provide a systematic review of S-SDH in the setting of SAH. METHODS A systematic literature review using PRISMA guidelines revealed 11 previous cases of concurrent intracranial SAH and spinal SDH, which are presented with our new reported Case. RESULTS Intracranial sources of spontaneous SAH included 8 aneurysms, 1 pseudoaneurysm, and 3 angiogram negative cases. Hunt Hess grade ranged from 1-4, mean time between SAH and S-SDH was 5.8 days, and S-SDH presented most frequently in the lumbar spine. 8 patients showed significant to complete clinical recovery, 2 had continued plegia of the lower extremities, and 2 expired. Modified Rankin score ranged from 0-6, with mRS > 2 for 4 out of 12 patients. Patients with a poor clinical outcome (mRS > 2) had an initially negative cerebral angiogram, earlier presentation with less time between SAH and S-SDH (0.8 vs 7.6 days), use of antithrombotic medication, no diversion of CSF, and cervical or thoracic S-SDH. CONCLUSION S-SDH is an uncommon occurrence in the setting of aneurysmal SAH with better outcomes associated with lumbar location, delayed presentation, CSF diversion, and lack of antithrombotic use. Conservative treatment may be sufficient in cases with delayed S-SDH and lack of significant neurological deficits. More reported cases will allow greater understanding of this clinical entity.