Diagnosis and management of a rare case of clival chordoma in a young male patient.

Chordomas are uncommon bone slow-growing tumors developing from remnants of the notochord. They are typically seen in adults, and rarely in children. We present the case of a 16-year-old male patient with a clival chordoma, presenting with progressive headache and diplopia. In this case report we aim to provide an educational explanation of the radiological findings, diagnostic challenges, and therapeutic and management strategies.

"TIPS" and Technical Nuances for Digital Illustration in Neurointerventional Surgery.

Medical illustrations represent a precious resource for learning surgical anatomy and surgical techniques, allowing pre- and postoperative reviews. As traditional hand-drawn illustrations are difficult to use and expressing the area of neurointerventional surgery is time-consuming, we proposed methods for neurointerventional surgeons to create digital illustrations (DIs) for neurointerventional surgery using the iPad-exclusive Procreate application (Savage Interactive, Hobart, Australia). Dedicated "digital pens" were created and used for each endovascular device, creating straightforward representations of neurointerventional procedures and changes over time. DIs in neurointervention easily depict changes to highlighted surgical scenes for various devices with complex configurations and structures. DIs are also versatile, allowing easy intra- and inter-institutional sharing and discussion of technical tips on the manipulation of medical devices (coils, catheters, stents, etc.) among neurointerventional surgeons worldwide. DIs can be applied as educational tools not only in neurointerventional surgery, but also in craniotomy surgery and for surgical records from other specialties.

A Case With Twists and Turns: A Report of Vertebrobasilar Dolichoectasia.

Vertebrobasilar dolichoectasia (VBD) is a rare anatomical abnormality of the vertebral artery system, defined as irregular expansion, elongation, and tortuosity of vertebral arteries. Anomalies of the vertebrobasilar artery can have a wide variety of clinical presentations, ranging from simple headaches to debilitating strokes. We present the case of an atypical presentation of VBD which mimicked trigeminal neuralgia by compressing the trigeminal nerve. There are currently no guidelines concerning the management of VBD, nor is there evidence of a definitive cure. This case invoked discussions among the medical team as to whether management should be medically or surgically focused, as well as long-term outcomes for patients with VBD. The superiority of medical versus surgical treatment of this issue is still a debated topic. This patient trialed medical management with dexamethasone and carbamazepine with no improvement in symptoms. He then underwent surgical gamma knife treatment but even this invasive measure was unsuccessful at relieving his symptoms. We hope that by presenting this case, we can display how the therapies available for VBD are limited and often unsuccessful in relieving the disease burden in patients with VBD.

Widespread haemorrhages in infants post-shunting (WHIPS): clinical features, risk factors and neuroimaging characteristics of a rare and under-recognised phenomenon.

PURPOSE: Infants undergoing CSF shunting procedures face a rare complication which we propose to rename "Widespread Haemorrhages in Infants Post-Shunting" (WHIPS) to better capture this unique phenomenon specific to infants undergoing CSF diversion. Our objective is to analyse the risk factors for WHIPS development and provide a detailed neuroradiological description of these haemorrhages. MATERIALS AND METHODS: A radiology information system (RIS) was searched using the search terms "shunt" and/or "catheter" and/or "drain" and/or "ventriculoperitoneal" and/or "VP" between September 2008 to January 2021 for patients < 12 months of age. Clinical data was compiled for each patient meeting the inclusion criteria. Included cases were reviewed by three radiologists for the presence of WHIPS with calculation of the bifrontal ratio and documenting haemorrhage number, morphology, location and lobar distribution. RESULTS: 51 patients met inclusion criteria, 8 WHIPS patients and 43 controls. There was a statistically significant correlation between a larger post-op head circumference and WHIPS (p = 0.04). WHIPS was associated with post-haemorrhagic hydrocephalus and post-infectious hydrocephalus (p = 0.009). WHIPS were identified in the cortico-subcortical regions, periventricular white matter, and deep white matter. Haemorrhages were either punctate, ovoid or confluent. Haemorrhages ranged from single to innumerable. CONCLUSIONS: WHIPS represent a rare and under-recognised complication of CSF shunting unique to the infantile population. We postulate deep and superficial medullary venous haemorrhage as an underlying mechanism related to disordered intracranial hydrodynamics which are exacerbated in the infantile population due to underdeveloped arachnoid granulations and a compliant skull.

Robust AI-Driven Segmentation of Glioblastoma T1c and FLAIR MRI Series and the Low Variability of the MRIMath© Smart Manual Contouring Platform.

Patients diagnosed with glioblastoma multiforme (GBM) continue to face a dire prognosis. Developing accurate and efficient contouring methods is crucial, as they can significantly advance both clinical practice and research. This study evaluates the AI models developed by MRIMath© for GBM T1c and fluid attenuation inversion recovery (FLAIR) images by comparing their contours to those of three neuro-radiologists using a smart manual contouring platform. The mean overall Sørensen-Dice Similarity Coefficient metric score (DSC) for the post-contrast T1 (T1c) AI was 95%, with a 95% confidence interval (CI) of 93% to 96%, closely aligning with the radiologists' scores. For true positive T1c images, AI segmentation achieved a mean DSC of 81% compared to radiologists' ranging from 80% to 86%. Sensitivity and specificity for T1c AI were 91.6% and 97.5%, respectively. The FLAIR AI exhibited a mean DSC of 90% with a 95% CI interval of 87% to 92%, comparable to the radiologists' scores. It also achieved a mean DSC of 78% for true positive FLAIR slices versus radiologists' scores of 75% to 83% and recorded a median sensitivity and specificity of 92.1% and 96.1%, respectively. The T1C and FLAIR AI models produced mean Hausdorff distances (<5 mm), volume measurements, kappa scores, and Bland-Altman differences that align closely with those measured by radiologists. Moreover, the inter-user variability between radiologists using the smart manual contouring platform was under 5% for T1c and under 10% for FLAIR images. These results underscore the MRIMath© platform's low inter-user variability and the high accuracy of its T1c and FLAIR AI models.

First multicenter study evaluating the utility of the BENCHMARKTM BMXTM 81 large-bore access catheter in neurovascular interventions.

INTRODUCTION: This study is the first multicentric report on the safety, efficacy, and technical performance of utilizing a large bore (0.081″ inner diameter) access catheter in neurovascular interventions. METHODS: Data were retrospectively collected from seven sites in the United States for neurovascular procedures via large bore 0.081″ inner diameter access catheter (Benchmark BMX81, Penumbra, Inc.). The primary outcome was technical success, defined as the access catheter reaching its target vessel. Safety outcomes included periprocedural device-related and access site complications. RESULTS: There were 90 consecutive patients included. The median age of the patients was 63 years (IQR: 53, 68); 53% were female. The most common interventions were aneurysm embolization (33.3%), carotid stenting (12.2%), and arteriovenous malformation embolization (11.1%). The transradial approach was most used (56.7%), followed by transfemoral (41.1%). Challenging anatomic variations included severe vessel tortuosity (8/90, 8.9%), type 2 aortic arch (7/90, 7.8%), type 3 aortic arch (2/90, 2.2%), bovine arch (2/90, 2.2%), and severe angle (<30°) between the subclavian artery and target vessel (1/90, 1.1%). Technical success was achieved in 98.9% of the cases (89/90), with six cases requiring a switch from radial to femoral (6.7%) and one case from femoral to radial (1.1%). There were no access site complications or complications related to the 0.081″ catheter. Two postprocedural complications occurred (2.2%), unrelated to the access catheter. CONCLUSION: The BMX™ 81 large-bore access catheters was safe and effective in both radial and femoral access across a wide range of neurovascular procedures, achieving high technical success without any access site or device-related complications.

Cerebellar Hemangioblastoma Mimicking Arteriovenous Malformation: A Case Report.

Hemangioblastoma (HBM) is a tumor distinguished by the presence of stromal cells and small vessels. These stromal cells represent stem cells, which, due to the influence of the neoplasm, proliferate and differentiate into "vasoformative elements" that create new blood vessels. Hemangioblastomas resemble arteriovenous malformation (AVM) in imaging features, characterized by an apparent vascular blush, the presence of multiple feeding vessels, and evident draining veins observed on digital subtraction angiography (DSA). Our study presents a case of HBM in the right cerebellar hemisphere mimicking AVM. The patient had been diagnosed with AVM in the same location two years ago and managed with endovascular embolization. One month prior, the patient experienced severe headaches, imbalance, nausea, left ear fullness, blurry vision, and high blood pressure. The imaging feature suggests HBM rather than AVM. The patient next underwent sub-occipital craniotomy and tumor resection with external ventricular drainage (EVD) insertion. The histopathological report of the excised mass confirmed HBM. In conclusion, AVM and HBM rarely occur together. Recent research indicates that HBM and AVM have exact embryologic origins and need later genetic alterations to develop into symptomatic lesions. Further research is required to clarify the uncommon combination of these lesions.

Unraveling the Predictors of Enlarged Perivascular Spaces: A Comprehensive Logistic Regression Approach in Cerebral Small Vessel Disease.

Background: This study addresses the predictive modeling of Enlarged Perivascular Spaces (EPVS) in neuroradiology and neurology, focusing on their impact on Cerebral Small Vessel Disease (CSVD) and neurodegenerative disorders. Methods: A retrospective analysis was conducted on 587 neurology inpatients, utilizing LASSO regression for variable selection and logistic regression for model development. The study included comprehensive demographic, medical history, and laboratory data analyses. Results: The model identified key predictors of EPVS, including Age, Hypertension, Stroke, Lipoprotein a, Platelet Large Cell Ratio, Uric Acid, and Albumin to Globulin Ratio. The predictive nomogram demonstrated strong efficacy in EPVS risk assessment, validated through ROC curve analysis, calibration plots, and Decision Curve Analysis. Conclusion: The study presents a novel, robust EPVS predictive model, providing deeper insights into EPVS mechanisms and risk factors. It underscores the potential for early diagnosis and improved management strategies in neuro-radiology and neurology, highlighting the need for future research in diverse populations and longitudinal settings.

Radiomics and artificial intelligence applications in pediatric brain tumors.

BACKGROUND: The study of central nervous system (CNS) tumors is particularly relevant in the pediatric population because of their relatively high frequency in this demographic and the significant impact on disease- and treatment-related morbidity and mortality. While both morphological and non-morphological magnetic resonance imaging techniques can give important information concerning tumor characterization, grading, and patient prognosis, increasing evidence in recent years has highlighted the need for personalized treatment and the development of quantitative imaging parameters that can predict the nature of the lesion and its possible evolution. For this purpose, radiomics and the use of artificial intelligence software, aimed at obtaining valuable data from images beyond mere visual observation, are gaining increasing importance. This brief review illustrates the current state of the art of this new imaging approach and its contributions to understanding CNS tumors in children. DATA SOURCES: We searched the PubMed, Scopus, and Web of Science databases using the following key search terms: ("radiomics" AND/OR "artificial intelligence") AND ("pediatric AND brain tumors"). Basic and clinical research literature related to the above key research terms, i.e., studies assessing the key factors, challenges, or problems of using radiomics and artificial intelligence in pediatric brain tumors management, was collected. RESULTS: A total of 63 articles were included. The included ones were published between 2008 and 2024. Central nervous tumors are crucial in pediatrics due to their high frequency and impact on disease and treatment. MRI serves as the cornerstone of neuroimaging, providing cellular, vascular, and functional information in addition to morphological features for brain malignancies. Radiomics can provide a quantitative approach to medical imaging analysis, aimed at increasing the information obtainable from the pixels/voxel grey-level values and their interrelationships. The "radiomic workflow" involves a series of iterative steps for reproducible and consistent extraction of imaging data. These steps include image acquisition for tumor segmentation, feature extraction, and feature selection. Finally, the selected features, via training predictive model (CNN), are used to test the final model. CONCLUSIONS: In the field of personalized medicine, the application of radiomics and artificial intelligence (AI) algorithms brings up new and significant possibilities. Neuroimaging yields enormous amounts of data that are significantly more than what can be gained from visual studies that radiologists can undertake on their own. Thus, new partnerships with other specialized experts, such as big data analysts and AI specialists, are desperately needed. We believe that radiomics and AI algorithms have the potential to move beyond their restricted use in research to clinical applications in the diagnosis, treatment, and follow-up of pediatric patients with brain tumors, despite the limitations set out.

Imaging Features of Immunodeficiency-Associated Primary CNS Lymphoma: A Review.

In the immunocompromised setting, there are distinct radiologic findings of primary central nervous system lymphoma (PCNSL), including necrotic ring-enhancing lesions, increased propensity for intralesional haemorrhage, and multiplicity. In this clinical context, advanced imaging with MR perfusion, spectroscopy, and diffusion-weighted imaging can be used to increase accuracy in the diagnosis of lymphoma over mimics such as high-grade glioma, metastases, or infection. This review summarizes the histology and pathophysiology of PCNSL in immunodeficient hosts, which provide a basis for its imaging appearances, prognosis, and treatment. This discussion is important for the general radiologist as the incidence of immunodeficiency-related PCNSL may be increasing.

Role of artificial intelligence in brain tumour imaging.

Artificial intelligence (AI) is a rapidly evolving field with many neuro-oncology applications. In this review, we discuss how AI can assist in brain tumour imaging, focusing on machine learning (ML) and deep learning (DL) techniques. We describe how AI can help in lesion detection, differential diagnosis, anatomic segmentation, molecular marker identification, prognostication, and pseudo-progression evaluation. We also cover AI applications in non-glioma brain tumours, such as brain metastasis, posterior fossa, and pituitary tumours. We highlight the challenges and limitations of AI implementation in radiology, such as data quality, standardization, and integration. Based on the findings in the aforementioned areas, we conclude that AI can potentially improve the diagnosis and treatment of brain tumours and provide a path towards personalized medicine and better patient outcomes.

CAD-Related Disorder (EIEE-50) in an Infant With Cortical Visual Impairment.

PURPOSE: To document the association of CAD-related disorder (EIEE-50) with cortical visual impairment. OBSERVATIONS: An 8-month-old Caucasian boy with whole genome sequencing confirming 2 variants in the gene CAD, who presented with severe seizures, microcephaly, hyperreflexia, hypotonia, anemia, and severe cortical visual impairment. Magnetic resonance imaging (MRI) of the brain noted thickened cortical gray matter along the right calcarine fissure as well as changes suggesting malformation of cortical development. Empiric uridine monophosphate supplementation has significantly improved seizure activity, hypotonia, and development and has led to resolution of anemia. CONCLUSIONS AND IMPORTANCE: CAD-related disorder is treatable and may affect visual cortical development causing severe secondary cortical visual impairment, a newly described clinical manifestation.

Effective and organ doses in patient undergoing interventional neuroradiology procedures: A multicentre study.

PURPOSE: Radiation doses to adult patients submitted to cerebral angiography and intracranial aneurysms treatments were assessed by using DICOM Radiation Dose Structured Reports (RDSR) and Monte Carlo simulations. Conversion factors to estimate effective and organ doses from Kerma-Area Product (PKA) values were determined. METHODS: 77 cerebral procedures performed with five angiographic equipment installed in three Italian centres were analyzed. Local settings and acquisition protocols were considered. The geometrical, technical and dosimetric data of 16,244 irradiation events (13305 fluoroscopy, 2811 digital subtraction angiography, 128 cone-beam CT) were extracted from RDSRs by local dose monitoring systems and were input in MonteCarlo PCXMC software to calculate effective and organ doses. Finally, conversion factors to determine effective and organ doses from PKA were determined. Differences between centres were assessed through statistical analysis and accuracy of dose calculation method based on conversion factors was assessed through Bland-Altman analysis. RESULTS: Large variations in PKA (14-561 Gycm2) and effective dose (1.2-73.5 mSv) were observed due to different degrees of complexity in the procedures and angiographic system technology. The most exposed organs were brain, salivary glands, oral mucosa, thyroid and skeleton. The study highlights the importance of recent technology in reducing patient exposure (about fourfold, even more in DSA). No statistically significant difference was observed in conversion factors between centres, except for some organs. A conversion factor of 0.09 ± 0.02 mSv/Gycm2 was obtained for effective dose. CONCLUSIONS: Organ and effective doses were assessed for neuro-interventional procedures. Conversion factors for calculating effective and organ doses from PKA were provided.

Automated vs. manual coding of neuroimaging reports via natural language processing, using the international classification of diseases, tenth revision.

Objective: Natural language processing (NLP) can generate diagnoses codes from imaging reports. Meanwhile, the International Classification of Diseases (ICD-10) codes are the United States' standard for billing/coding, which enable tracking disease burden and outcomes. This cross-sectional study aimed to test feasibility of an NLP algorithm's performance and comparison to radiologists' and physicians' manual coding. Methods: Three neuroradiologists and one non-radiologist physician reviewers manually coded a randomly-selected pool of 200 craniospinal CT and MRI reports from a pool of >10,000. The NLP algorithm (Radnosis, VEEV, Inc., Minneapolis, MN) subdivided each report's Impression into "phrases", with multiple ICD-10 matches for each phrase. Only viewing the Impression, the physician reviewers selected the single best ICD-10 code for each phrase. Codes selected by the physicians and algorithm were compared for agreement. Results: The algorithm extracted the reports' Impressions into 645 phrases, each having ranked ICD-10 matches. Regarding the reviewers' selected codes, pairwise agreement was unreliable (Krippendorff α = 0.39-0.63). Using unanimous reviewer agreement as "ground truth", the algorithm's sensitivity/specificity/F2 for top 5 codes was 0.88/0.80/0.83, and for the single best code was 0.67/0.82/0.67. The engine tabulated "pertinent negatives" as negative codes for stated findings (e.g. "no intracranial hemorrhage"). The engine's matching was more specific for shorter than full-length ICD-10 codes (p = 0.00582x10-3). Conclusions: Manual coding by physician reviewers has significant variability and is time-consuming, while the NLP algorithm's top 5 diagnosis codes are relatively accurate. This preliminary work demonstrates the feasibility and potential for generating codes with reliability and consistency. Future works may include correlating diagnosis codes with clinical encounter codes to evaluate imaging's impact on, and relevance to care.

Multicenter comparison using two AI stroke CT perfusion software packages for determining thrombectomy eligibility.

BACKGROUND: Stroke AI platforms assess infarcted core and potentially salvageable tissue (penumbra) to identify patients suitable for mechanical thrombectomy. Few studies have compared outputs of these platforms, and none have been multicenter or considered NIHSS or scanner/protocol differences. Our objective was to compare volume estimates and thrombectomy eligibility from two widely used CT perfusion (CTP) packages, Viz.ai and RAPID.AI, in a large multicenter cohort. METHODS: We analyzed CTP data of acute stroke patients with large vessel occlusion (LVO) from four institutions. Core and penumbra volumes were estimated by each software and DEFUSE-3 thrombectomy eligibility assessed. Results between software packages were compared and categorized by NIHSS score, scanner manufacturer/model, and institution. RESULTS: Primary analysis of 362 cases found statistically significant differences in both software's volume estimations, with subgroup analysis showing these differences were driven by results from a single scanner model, the Canon Aquilion One. Viz.ai provided larger estimates with mean differences of 8cc and 18cc for core and penumbra, respectively (p<0.001). NIHSS subgroup analysis also showed systematically larger Viz.ai volumes (p<0.001). Despite volume differences, a significant difference in thrombectomy eligibility was not found. Additional subgroup analysis showed significant differences in penumbra volume for the Phillips Ingenuity scanner, and thrombectomy eligibility for the Canon Aquilion One scanner at one center (7 % increased eligibility with Viz.ai, p=0.03). CONCLUSIONS: Despite systematic differences in core and penumbra volume estimates between Viz.ai and RAPID.AI, DEFUSE-3 eligibility was not statistically different in primary or NIHSS subgroup analysis. A DEFUSE-3 eligibility difference, however, was seen on one scanner at one institution, suggesting scanner model and local CTP protocols can influence performance and cause discrepancies in thrombectomy eligibility. We thus recommend centers discuss optimal scanning protocols with software vendors and scanner manufacturers to maximize CTP accuracy.

Acute bilateral sensorineural hearing loss as presentation of leptomeningeal metastases.

We describe a rare occurrence of bilateral acute severe sensorineural hearing loss in a middle-aged man that heralded the diagnosis of metastatic gastric cancer.

A Severe Case of Streptococcus pneumoniae Meningoencephalitis in an Infant Resulting in Fatal Strokes.

Streptococcus pneumoniae (S. Pneumoniae) is a common cause of bacterial meningitis in the pediatric population, but rarely causes complications such as encephalitis, abscess, and seizures with the prompt initiation of proper antimicrobial therapy. In this report, we present a rare and severe case of S. Pneumoniae meningoencephalitis in a full term 6-month-old which progressed to multiple cerebral and cerebellar infarcts with concomitant cerebellar tonsillar herniation and hypercarbic respiratory failure requiring intubation and mechanical ventilation despite early initiation of antibiotics. Given the patient's clinical status and poor neurological prognosis, the family eventually opted for palliative extubation.

Multisystem factors contributing to redundant intracranial vascular imaging in the ED.

PURPOSE: To evaluate the multisystem factors contributing to redundant neurovascular orders in the ED. METHODS: This was an IRB-approved, retrospective study, performed at a single institution examining a 5-year history of redundant CTA/MRA head and neck (HN) exams performed in the ED for patients with no documented clinical change in mental status/neurological exam necessitating additional imaging. Factors contributing to redundant ordering including provider experience, synchronous order placement, and radiologist recommendations were examined. Additionally, the impact of duplicative imaging in terms of medical cost and ED length of stay was evaluated. RESULTS: 250 patients met inclusion criteria with both CTA/MRA of the HN performed during a single ED encounter (total 500 exams). 190 (76%) redundant exams were not recommended by a radiologist and contributed to an added ED length of stay of 3.6 h on average. Provider experience was not a significant contributing factor. 60 (24%) of redundant exams were recommended by a radiologist and were most frequently CTAs needed to clarify an area of artifact/high-grade stenosis/occlusion on a primary MRA exam. CONCLUSION: Evaluation of contributing factors to redundant CTA/MRA HN exams ordering has highlighted multiple associated factors including provider experience, recommendations by radiologists for clarification of MRA findings, as well as systems processes related to synchronous CTA/MRA order placement.