Neurological Diagnosis: Artificial Intelligence Compared With Diagnostic Generator.

OBJECTIVE: Artificial intelligence has recently become available for widespread use in medicine, including the interpretation of digitized information, big data for tracking disease trends and patterns, and clinical diagnosis. Comparative studies and expert opinion support the validity of imaging and data analysis, yet similar validation is lacking in clinical diagnosis. Artificial intelligence programs are here compared with a diagnostic generator program in clinical neurology. METHODS: Using 4 nonrandomly selected case records from New England Journal of Medicine clinicopathologic conferences from 2017 to 2022, 2 artificial intelligence programs (ChatGPT-4 and GLASS AI) were compared with a neurological diagnostic generator program (NeurologicDx.com) for diagnostic capability and accuracy and source authentication. RESULTS: Compared with NeurologicDx.com, the 2 AI programs showed results varying with order of key term entry and with repeat querying. The diagnostic generator yielded more differential diagnostic entities, with correct diagnoses in 4 of 4 test cases versus 0 of 4 for ChatGPT-4 and 1 of 4 for GLASS AI, respectively, and with authentication of diagnostic entities compared with the AI programs. CONCLUSIONS: The diagnostic generator NeurologicDx yielded a more robust and reproducible differential diagnostic list with higher diagnostic accuracy and associated authentication compared with artificial intelligence programs.

MR Imaging Patterns and Prognosis in Powassan Virus Encephalitis.

BACKGROUND: Powassan virus (POWV) encephalitis is an arbovirus infection and the only tick-borne encephalitis serogroup which is present in mainland North America. The magnetic resonance (MR) imaging described with POWV encephalitis is varied, nonspecific, and limited in number, and as such, imaging patterns and outcomes with this arbovirus infection are not well appreciated. METHODS: A case report and literature review of the MR imaging associated with POWV encephalitis and correlate of the MR pattern with outcome is considered. RESULTS: The cerebellar dominant MR imaging pattern was identified in 50% of POWV encephalitis cases and was associated with a 60% fatality rate. POWV encephalitis with prominent cerebellar involvement on MR imaging responded to intravenous steroid. CONCLUSIONS: A cerebellar dominant MR pattern in POWV encephalitis was common, associated with a poor prognosis, and recognition could change management from supportive to life-saving.

Biopsy negative giant cell arteritis-Revised diagnostic criteria: Giant cell arteritis diagnostic criteria.

BACKGROUND: Diagnosis of giant cell arteritis has traditionally relied on demonstration of pathologic changes on temporal artery biopsy. METHOD: To highlight recent advances in large vessel imaging resulting in revised diagnostic criteria for giant cell arteritis. CONCLUSION: We call attention to the revised diagnostic criteria imaging evidence of extracranial large vessel thickening as an alternative to temporal artery biopsy in diagnosis of giant cell arteritis in a patient with heralding anterior fornix infarct.

MR Three-Territory Sign in Cancer-Associated Hypercoagulation Stroke (Trousseau Syndrome): An Overlooked Diagnostic Feature: MR Three-Territory Sign.

BACKGROUND: Stroke in the setting of three-territory lesion pattern on magnetic resonance-diffusion-weighted imaging "three-territory sign" (TTS) is predominately due to cancer-associated hypercoagulation (CAH). Our goal is to determine the frequency with which "TTS" is overlooked as a diagnostic feature of cancer-associated hypercoagulation stroke. METHODS: Over a 4-year period (October 2016 to October 2020), stroke admissions with magnetic resonance imaging defined three-territory diffusion-weighted imaging lesions were identified. Patients were prospectively accrued in an observational study from the neurology service at Hartford Hospital, a 938 bed facility with a comprehensive stroke center with 2792 stroke admissions during the study period. RESULTS: Twenty-two patients met selection criteria, 4 due to infectious endocarditis, 16 due to stroke from CAH and 2 with no identifiable etiology. Of the 16 CAH patients, 5 were male and 11 female, mean age=72 (range: 47 to 91). Cancer type (biopsy proven unless noted) was cholangiocarcinoma=3, adenocarcinoma of lung=3, adenocarcinoma of breast=1, pancreatic carcinoma=3 (2 biopsy, 1 ultrasound), adenocarcinoma, origin unknown=1, non-small cell carcinoma of lung=2, carcinoid=1, ovarian carcinoma=1, lung mass (not biopsied)=1. Malignancy was known in 7 and occult in 9 at stroke presentation. Consideration of malignancy-related hypercoagulation as the cause of stroke was appreciated in 1 of 16 radiology reports and in 4 of 16 neurology admission notes. CONCLUSION: TTS is a frequently missed diagnostic magnetic resonance feature in cancer-associated hypercoagulation stroke and often heralds occult malignancy.

MR Target Sign in Cerebral Aspergillosis.

Magnetic resonance (MR) is an effective imaging modality in the evaluation of infectious brain disease, yet findings are often nonspecific. The presence of a diagnostic feature can facilitate early treatment, particularly where mortality is high. We highlight MR apparent diffusion coefficient/T2-weighted target sign in the diagnosis of cerebral aspergillosis.

Optic Nerve Enhancement and Restricted Diffusion in Postoperative Visual Loss.

Postoperative visual loss is rare and most often due to posterior ischemic optic neuropathy. We describe optic nerve MR imaging of a 37-year-old man with postoperative visual loss due to posterior ischemic optic neuropathy after complicated aortic aneurysm surgery. MR demonstrated restricted diffusion and focal enhancement of both optic nerves. Combined restricted diffusion and focal enhancement is a unique MR imaging feature with postoperative vision loss.

Three Territory Sign: An MRI marker of malignancy-related ischemic stroke (Trousseau syndrome).

BACKGROUND: Multiple acute cerebral territory infarcts of undetermined origin are typically attributed to cardioembolism, most frequently atrial fibrillation. However, the importance of 3-territory involvement in association with malignancy is under-recognized. We sought to highlight the "Three Territory Sign" (TTS) (bilateral anterior and posterior circulation acute ischemic diffusion-weighted imaging [DWI] lesions), as a radiographic marker of stroke due to malignancy. METHODS: We conducted a single-center retrospective analysis of patients from January 2014 to January 2016, who suffered an acute ischemic stroke with MRI-DWI at our institution, yielding 64 patients with a known malignancy and 167 patients with atrial fibrillation, excluding patients with both to eliminate bias. All DWI images were reviewed for 3-, 2-, and 1-territory lesions. Chi-square test of proportion was used to test significance between the 2 groups. RESULTS: We found an association between the groups (malignancy vs atrial fibrillation) and the number of territory infarcts (p < 0.0001). Pairwise comparisons using the Holm p value adjustment showed no difference between 1- and 2-territory patterns (p = 0.465). However, the TTS was 6 times more likely observed within the malignancy cohort as compared to patients with atrial fibrillation (23.4% [n = 15] vs 3.5% [n = 6]) and was different from both 1-territory (p < 0.0001) and 2-territory patterns (p = 0.0032). CONCLUSION: The TTS is a highly specific marker and 6 times more frequently observed in malignancy-related ischemic stroke than atrial fibrillation-related ischemic stroke. Evaluation for underlying malignancy in patients with the TTS is reasonable in patients with undetermined etiology.

Early Magnetic Resonance Imaging Decreases Hospital Length of Stay in Patients with Ischemic Stroke.

BACKGROUND: Imaging modalities are important part of stroke evaluation. Noncontrast head computed tomography (CT) is the initial imaging modality in acute stroke and although important to rule out acute hemorrhage and making a decision on thrombolytic treatment, ischemic changes may not be visible on CT for up to 24 hours. Magnetic resonance imaging (MRI) brain is an invaluable tool to confirm an ischemic stroke and facilitates stroke evaluation. Objective of this study was to investigate the correlation between time to MRI and length of hospital stay. METHODS: A total of 432 patients admitted to Hartford Hospital (Comprehensive Stroke Center) with a focal neurological deficit in the year 2014 and got a CT head and MRI brain were enrolled in the study. Data collection was done via stroke database and retrospective chart review. Patients with any hemorrhage or age <18 years were excluded from the study. Patients were categorized as having had an early (within 12 hours) or a late (more than 12 hours) MRI. We used chi-square and Wilcoxon ranked sum test to compare time from arrival to MRI and length of stay in the hospital. RESULTS: There was a statistically significant difference in hospital length of stay between patients who obtained MRI within 12 hours, as compared with patients who had MRI greater than 12 hours after admission, early MRI group 3 days (1.8, 4.9) versus 4 days (2.6, 7.0), P < .001. CONCLUSIONS: Our study suggests that brain MRI performed within 12 hours of admission facilitates stroke evaluation and decreases hospital length of stay. It provides evidence for cost effectiveness of MRI in ischemic stroke.

A Fatal Case of Undiagnosed Candida Meningitis: Role of Computer-assisted Diagnosis.

Diagnostic error is an increasing health care concern. An intravenous drug abuser with chronic meningitis died after a prolonged hospitalization from fungal meningitis diagnosed at autopsy. We examine the diagnostic pitfalls and consider how a computer-assisted diagnostic system may influence the outcome of an otherwise fatal condition.

Computer-assisted Diagnostic Checklist in Clinical Neurology.

Considering computers are more efficient at processing large amounts of information than the human brain, speaks to the need to explore more intelligent computer-assisted diagnostic approaches. Two diagnostic checklist programs, one for single key term entry (NeurologyINDEX), and another, with more advanced algorithms to process multiple key terms and perform additional functions (NeurologicDx) are discussed. Both programs are internet based, access the same database, and are designed to generate diagnostic checklists and disease profiles accessible with hand-held or other computer device. The development of systems that use "smart algorithms" to generate valid diagnostic checklists is the goal.

Bilateral pallidal hemorrhage in toxoplasmosis update of acute symmetric lesions of deep nuclei.

As acute symmetric lesions of deep gray nuclei are often associated with an impaired level of consciousness and neuroimaging by itself cannot distinguish between etiologies, diagnosis may be problematic. Appreciation of the cause of the various neuroimaging patterns in conjunction with the history, examination and laboratory investigations allows for accurate diagnosis in the vast majority of cases. Given the metabolic vulnerability of deep gray nuclei, other than bi-thalamic infarction, it follows that toxic-metabolic and hypoxic-ischemic events account for the majority of cases. Nevertheless, the differential diagnosis is broad and diverse. We here describe two cases of bilateral pallidal hemorrhage in AIDS-associated toxoplasmosis, and review conditions recently described with acute symmetric deep gray nuclei lesions on neuroimaging.

Symmetric Basal Ganglia lesion in a diabetic dialysis patient: recurrence and pathogenesis.

This paper describes a diabetic dialysis patient presenting two episodes of symmetric basal ganglia lesions occurring 18 months apart, and discusses the MR imaging findings and the pathogenesis of this condition.

The etiology of ring lesions on diffusion-weighted imaging.

This study describes a series of cases and reviews the literature on cases of ring lesion on diffusion-weighted imaging to better appreciate the spectrum of disease associated with this neuroimaging finding. We retrospectively reviewed the MR studies of 15 patients with ring pattern lesions on diffusion-weighted imaging from an inpatient Neurology service of a tertiary care center seen over a ten-year period, and reviewed cases in the literature. Thirty-one cases, including 15 new patients, comprise the study group. Immunocompromised patients accounted for 38% of patients with ring lesions on diffusion-weighted imaging with cerebral aspergillosis in five patients, progressive multifocal leukoencephalopathy in three, primary CNS lymphoma in two, cerebral toxoplasmosis in one, and resolving cerebral hematoma in one. In the immunocompetent group demyelinating lesions including multiple sclerosis, acute disseminated encephalomyelitis, Balo's concentric sclerosis and acute necrotizing encephalitis, were seen in 11 patients, vascular etiology in four and neoplastic in three patients, two primary and one metastatic and pyogenic brain abscess in one. Ring lesions on diffusion-weighted imaging are associated with a spectrum of disease not previously considered. Immunocompromised patients accounted for almost one-half while demyelinating conditions in the immunocompetent patients were most common overall.