Glioblastoma IDH-wild type, CNS WHO grade 4 (GBM) can be diagnosed on the basis of histologic features (histological-GBM) or molecular features (molecular-GBM). Only few studies report neuroimaging features of GBM in its modern classification, and none have controlled for surgical status or used multiple logistic regression analysis to determine unique predictors. Our study aimed to validate MRI features that distinguish histological-GBM and molecular-GBM. We analyzed a training cohort (n = 255) and validation cohort (n = 44) of GBM cases, classified according to the 2021 WHO Classification of Tumors of the CNS. For the training cohort, univariate and multiple logistic regression analyses determined if MRI metrics (contrast enhancement, ring-enhancement, vasogenic edema, multifocal tumor, lesion diameter, hemorrhage, number of lobes, and normalized ADC) and surgery type (biopsy vs. resection) predicted GBM-type (histological vs. molecular). A reduced multiple logistic regression model was constructed and applied to the validation dataset. There were 231 histological-GBMs and 24 molecular-GBMs in the training cohort. Multiple logistic regression analysis including both MRI metrics and surgery type showed that contrast enhancement (OR 7.83 [95

Neuroimaging is an essential part of the case selection, delivery, and post-treatment assessment and management of stereotactic radiosurgery patients. With the advent of computed tomography (CT) and then brain magnetic resonance imaging (MRI), the delivery of radiosurgery became more refined. Now, virtually all radiosurgical devices allow the integration of advanced neuroimaging modalities for the purposes of treatment planning. Careful definition of the target volume as well as the adjacent critical structures is essential to optimal radiosurgery delivery. Further advances in neuroimaging will likely lead to improvements in the practice of radiosurgery.

PET imaging plays a vital role in the initial staging and post-treatment surveillance of patients with head and neck cancer. Although fluoro-d-glucose-PET remains the workhorse of PET imaging, novel tracers promise in being able to improve staging accuracy, refine radiation planning, and also provide tissue-specific diagnoses. Response assessment on PET may be accomplished using qualitative methods and by a variety of quantitative methods that have been validated in clinical trials. Simultaneous PET-MR is a promising technique, the implementation of which faces obstacles primarily related to cost, operation, availability, and lack of standardization of imaging techniques.

BackgroundBrain metastases (BMETS) from prostate cancer are rare. Hence, brain imaging in neurologically asymptomatic patients with advanced prostate cancer (aPC) is not routinely performed. Prostate-specific membrane antigen (PSMA) PET/CT uses a radiotracer that binds to prostate cancer epithelial cells and is FDA-approved for initial staging for high-risk prostate cancer, detecting prostate cancer recurrence, and determining eligibility for radionuclide therapy.MethodsWe report six patients with asymptomatic BMETS from aPC found on staging PSMA PET/CT or MRI. Along with cranial MRI, PSMA PET/CT may be useful for detecting asymptomatic intracranial metastasis in select patients with prostate cancer.ResultsBrain metastases were diagnosed in four patients by staging PSMA PET/CT scan-three after systemic disease progression and one during routine surveillance. In two other patients, BMETS were detected using MRI despite negative PSMA PET/CT for brain lesions. All were neurologically asymptomatic. Three patients had undetectable serum prostate-specific antigen (PSA) concentrations; one had neuroendocrine differentiation on histology.ConclusionIn patients with poorly differentiated or neuroendocrine aPC, BMETS may occur without neurologic symptoms and stable PSA. PSMA PET/CT may complement brain MRI for identifying BMETS in these patients.

Surgery is an option for eligible patients with medically refractory epilepsy. Presurgical neuroimaging is tailored to allow identification of structural abnormalities in areas corresponding to the epileptogenic zone, which is identified with other techniques, impacting postsurgical outcomes toward seizure freedom. In some cases, it is also important to identify the eloquent cortex and critical white matter tracts, which aid in surgical planning and counseling for patients. Invasive procedures such as hemispherectomy, corpus callosotomy, and lobectomy have existed for decades for the management of refractory epilepsy, but the arsenal of surgical options for epilepsy has expanded recently, with the introduction of newer minimally invasive treatments such as laser interstitial thermal therapy, focused US, gamma knife radiosurgery, and neuromodulatory procedures such as vagal nerve stimulation, deep brain stimulation, and responsive neurostimulation. Invasive intracranial monitoring, which includes placement of subdural electrodes and stereoelectroencephalography, is another important surgical procedure used for more precise localization of the epileptogenic zone before planning definitive surgery. The authors outline the indications, expected imaging appearances, and complications of invasive and minimally invasive surgical treatments of epilepsy to create familiarity with these procedures in the imaging community. Also discussed are MRI safety concerns involved in imaging patients with medically refractive epilepsy. ©RSNA, 2025 Supplemental material is available for this article. See the invited commentary by Pai and Jabhedar Maralani in this issue.

COVID-19 infection is associated with stroke due to various proposed mechanisms, including cerebral vasculitis, arterial and venous thrombosis. Vessel wall imaging, although not pathognomonic, interpreted in the appropriate clinical context and supportive laboratory findings, can help clarify the diagnosis and differentiate the etiology from other mechanisms of CNS involvement. We describe a patient with extensive anterior circulation vasculitis and ischemic stroke in the setting of COVID-19, with sparing of the posterior circulation.

BACKGROUND:Oncocytic carcinoma (OCA) was recently reclassified as a distinct differentiated thyroid carcinoma (DTC). Given its rarity, OCA studies are limited. This study describes the characteristics of OCA in a 20-year cohort. METHODS:Retrospective analysis of patients with OCA at a single tertiary care hospital from 2000 to 2021. RESULTS:Fifty-one OCA patients (22M:29F) were identified. The mean age at diagnosis was 60.3 years; 90% presented as palpable mass; 24% had a family history of thyroid cancer. None had vocal fold paresis. On ultrasound, most tumors were solid and hypoechoic. FNA (n = 14) showed Bethesda-4 lesions in 93%. All were treated surgically. Histologically, 63% demonstrated angioinvasion, 35% had lymphovascular invasion, and 15% had extrathyroidal extension. Radioactive iodine was used as adjunct therapy in 77%. CONCLUSION:OCA has distinct features that distinguish it from other DTCs, and additional focused studies will help clarify the aggressive nature, treatment options, and prognosis of the disease.

Follicular lymphoma is the most common indolent non- Hodgkin lymphoma (NHL) and accounts for approximately 20-30% of all NHL cases in Western countries. In general, systemic therapies are not considered to be curative. Despite this, prognosis is excellent with a 5-year relative survival rate of 90% and median overall survival rates ranging from 10-20 years across numerous studies. The exact incidence of central nervous system (CNS) involvement in cases of follicular lymphoma is unknown, however retrospective data suggest an incidence of 0.2% though this likely represents an underestimation of the true incidence. The optimum treatment approach for CNS disease in follicular lymphoma is poorly defined and no randomized studies exist which prove the superiority of one approach over another. Retrospective data suggest that resection, with or without adjuvant radiation, is an effective strategy for patients with local disease limited to the CNS. In cases where synchronous systemic disease is present, treatment regimens incorporating high-dose methotrexate and bendamustine or anthracycline-based chemotherapy have demonstrated efficacy. We report a case of a 59-year-old female with stage IV follicular lymphoma with synchronous systemic and leptomeningeal involvement who achieved complete remission following treatment with bendamustine, rituximab, and intra-thecal methotrexate. More long-term follow up data are needed to better characterize the prognosis for patients with CNS involvement who obtain complete remission following initial therapies. Treatment selection for patients with CNS involvement should take into account the presence or absence of systemic disease, patient comorbidities and performance status, and the likelihood of transformation to a high-grade process.

The ulnar nerve is the second most commonly entrapped nerve after the median nerve. Although clinical evaluation and electrodiagnostic studies remain widely used for the evaluation of ulnar neuropathy, advancements in imaging have led to increased utilization of these newer / better imaging techniques in the overall management of ulnar neuropathy. Specifically, high-resolution ultrasonography of peripheral nerves as well as MRI has become quite useful in evaluating the ulnar nerve in order to better guide treatment. The caliber and fascicular pattern identified in the normal ulnar nerves are important distinguishing features from ulnar nerve pathology. The cubital tunnel within the elbow and Guyon’s canal within the wrist are important sites to evaluate with respect to ulnar nerve compression. Both acute and chronic conditions resulting in deformity, trauma as well as inflammatory conditions may predispose certain patients to ulnar neuropathy. Granulomatous diseases as well as both neurogenic and non-neurogenic tumors can also potentially result in ulnar neuropathy. Tumors around the ulnar nerve can also lead to mass effect on the nerve, particularly in tight spaces like the aforementioned canals. Although high-resolution ultrasonography is a useful modality initially, particularly as it can be helpful for dynamic evaluation, MRI remains most reliable due to its higher resolution. Newer imaging techniques like sonoelastography and microneurography, as well as nerve-specific contrast agents, are currently being investigated for their usefulness and are not routinely being used currently.

Pulmonary infections contribute substantially to emergency department (ED) visits, posing a considerable health burden. Lower respiratory tract infections are prevalent, particularly among the elderly, constituting a significant percentage of infectious disease-related ED visits. Timely recognition and treatment are crucial to mitigate morbidity and mortality. Imaging studies, primarily chest radiographs and less frequently CT chests, play a pivotal role in diagnosis. This article aims to elucidate the imaging patterns of both common and rare pulmonary infections (bacterial and viral) in the post COVID-19 era, emphasizing the importance of recognizing distinct radiological manifestations. The integration of clinical and microbiological evidence aids in achieving accurate diagnoses, and guiding optimal therapeutic interventions. Despite potential overlapping manifestations, a nuanced understanding of radiological patterns, coupled with comprehensive clinical and microbiological information, enhances diagnostic precision in majority cases.

Rationale: Nervous system toxicity is a rare complication of metronidazole. Prompt identification of metronidazole toxicity combined with a comprehensive physical rehabilitation program is essential to maximizing the patient’s functional outcome. Patient concerns: A 58-year-old female was treated with metronidazole for embolic versus hematogenous spread of bacteria resulting in multifocal brain abscesses. Two weeks after discharge, the patient returned to the emergency department with slurred speech, muscle aches, generalized weakness, inability to ambulate, and poor oral intake. Diagnosis: Head magnetic resonance imaging revealed symmetric enhanced T2/FLAIR signaling in the dentate nuclei were also present bilaterally, a finding pathognomonic for metronidazole toxicity. Intervention: Metronidazole was discontinued, and the patient was enrolled in a comprehensive rehabilitation program. Outcomes: She began inpatient rehabilitation dependent for all activities of daily living and requiring moderate assistance for transfers. She could only walk 10 feet with a front-wheeled walker with a 2-person assist. The patient rapidly improved with a comprehensive rehabilitation program, and due to these improvements, she was discharged after 5 days of inpatient rehabilitation. At the time of discharge, she was independent with all activities of daily living and could walk 160 feet independently with a front-wheeled walker. Lessons: Prompt recognition and discontinuation of metronidazole remains the only known effective treatment. A comprehensive approach to treatment and rehabilitation is achieved with an early referral to rehabilitation services. This is crucial to minimize morbidity and optimize functional outcomes in this patient population.

Background and Objectives: Neuropsychological research on mesial temporal lobe epilepsy (MTLE) often highlights material-specific memory deficits, but a lesion-focused model may not accurately reflect the underlying networks that support episodic memory in these patients. Our study evaluated the pathophysiology behind verbal learning/memory deficits as revealed by hypometabolism quantified through 18-fluorodeoxyglucose positron emission tomography (FDG-PET).Methods: This retrospective study included thirty presurgical patients with intractable unilateral MTLE who underwent interictal FDG-PET and verbal memory assessment (12 females, mean age: 38.73 years). Fluorodeoxyglucose-positron emission tomography mapping was performed with voxel-based mapping of glucose utilization to a database of age-matched controls to derive regional Z-scores. Neuropsychological outcome variables included scores on learning and recall trials of two distinct verbal memory measures validated for use in epilepsy research. Pearson's correlations evaluated relationships between clinical variables and verbal memory. Linear regression was used to relate regional hypometabolism and verbal memory assessment. Post hoc analyses assessed areas of FDG-PET hypometabolism (threshold Z <= -1.645 below mean) where verbal memory was impaired.Results: Verbal memory deficits correlated with hypometabolism in limbic structures ipsilateral to language dominance but also correlated with hypometabolism in networks involving the ipsilateral perisylvian cortex and contralateral limbic and nonlimbic structures. Discussion: We conclude that traditional models of verbal memory may not adequately capture cognitive deficits in a broader sample of patients with MTLE. This study has important implications for epilepsy surgery protocols that use neuropsychological data and FDG-PET to draw conclusions about surgical risks.(c) 2023 Elsevier Inc. All rights reserved.

Background: Peripheral T-cell lymphomas (PTCLs) are uniquely sensitive to epigenetic modifiers. Our group previously demonstrated that combinations of epigenetic modifiers such as histone deacetylase inhibitors (HDACi), hypomethylating agents and pralatrexate produced potent synergy in pre-clinical models of PTCL, which produced compelling activity in early phase clinical studies. We have demonstrated that epigenetic modifiers, such as decitabine and 5-azacytidine (Marchi et al; Br. J. Haematol. 171, 2015) induces the expression of cancer testis antigens and established that pralatrexate acts as an immunomodulatory agent affecting genes involved in cytokine production, viral response and apoptosis. These pre-clinical data suggest a role for the incorporation of the immune-checkpoint inhibitor, pembrolizumab, to epigenetic backbones. Herein, we report on the differential clinical activity of adding the immune checkpoint inhibitor, pembrolizumab, to decitabine, pralatrexate, or the combination and we describe the role of cytokines as a biomarker of treatment response. Trial Design & Methods: This is a phase 1b study of pembrolizumab combined with pralatrexate alone (Arm A), with pralatrexate + decitabine (Arm B), or decitabine alone (Arm C) in patients with relapsed and refractory PTCL and CTCL. A standard 3+3 dose-escalation was applied in the doublet Arms (A and C) while a DLT-adapted partial order continual reassessment method (POCRM) for dose-finding with combinations of agents was applied in the triplet Arm (Arm B). We evaluated the cytokine profile using a Luminex-based immunoassay on serum samples obtained from trial patients on days 1, 8 and 15 during cycle 1 of treatment. Quantitative changes in 25 unique cytokines were evaluated, and these changes were correlated with clinical outcomes. Results: We enrolled 15 patients with six patients in Arm A, four in Arm B, and five in Arm C. All patients that received at least one dose of drug were evaluable for toxicity. One dose limiting toxicity (DLT) was observed in Arms A and B (grade 3 thrombocytopenia and febrile neutropenia, respectively). In Arm C, three DLTs were observed including one patient with grade 3 hyponatremia and rash; one patient with grade 4 thrombocytopenia, neutropenia, and anemia; and one patient with grade 4 neutropenia. There were no treatment related deaths. Nine patients out of 15 were evaluable for response at the time of this analysis. Of these nine evaluable patients, one achieved a complete remission (Arm B), two achieved partial remission (1 in Arm A, 1 in Arm B), one had stable disease (Arm C), and five experienced disease progression (2 in Arm A, 1 in Arm B, and 2 in Arm C). Interestingly, two of the three responses were seen in patients who received the triplet of pralatrexate, decitabine, and pembrolizumab (Arm B) and one response was seen in a patient treated with pralatrexate and pembrolizumab (Arm A). The serum cytokine profile revealed significant changes in only five of the 25 cytokines surveyed. Of the five cytokines, three pro-inflammatory cytokines, TNFα, MIP-3α and IL-10, measured at day 1 pre-treatment exhibited significantly higher levels (p= 0.0001, 0.0008 and 0.003 respectively) compared to healthy controls. Trial patients who responded to treatment (PR/CR) in either Arms demonstrated a decline in serum levels of TNFα and IL-10 by day 15 of cycle 1, whereas non-responders (PD/SD) showed stable to increased levels of both TNFα (Figure 1) and IL-10. Conclusion: These preliminary data suggest that the integration of pembrolizumab into an epigenetic backbone is safe and demonstrates encouraging responses in heavily pretreated patients with PTCL and CTCL. Pharmacodynamic data suggests that certain cytokines might have predictive value as biomarkers of disease response and progression. Interestingly, patients that responded (PR/CR) to the study drugs displayed a decline in cytokine levels, highlighting the prognostic implications of these cytokines. Additional pharmacodynamic studies, including flow cytometry of peripheral blood mononuclear cells, and pharmacokinetic studies are ongoing. Clinical trial registry NCT03240211. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Aim: CT guided technetium99m-macroaggregated albumin (99mTc-MAA) injection for lung nodule localization prior to video-assisted thoracoscopic surgery (VATS) is employed at our institution for more than a decade. We retrospectively studied the success rate, factors that affect outcomes, and complications of this procedure.Materials and methods: 147 patients with 164 nodules underwent this procedure before VATS. Imaging and procedure characteristics, complications of the procedure, successful intra-operative localization and wedge resection, if there was conversion of primary VATS to open thoracotomy and if so the reason, and histopathological diagnosis for each nodule were reviewed by two radiologists in consensus. In case of unsuccessful wedge resection, reasons for failure were derived from electronic medical record. The impact of nodule and procedure characteristics on successful intra-operative localization was assessed.Results: Excluding 9 nodules with unsuccessful localization due to non-procedure related reasons, the CT guided procedure was successful in 96.1% for intraoperative localization (149/155). Pleural leak of the radiotracer, split injection within the lobe, injection into a wrong nodule and gamma probe malfunction were primary reasons for failure. Nodule size, depth from pleura, and time between radiotracer injection and surgical incision did not impact success of the procedure. Among the 6 cases with procedure related failure, only 1 required conversion to open thoracotomy.Conclusion: CT guided 99mTc-MAA injection for intra-operative lung nodule localization is a feasible procedure with a high success rate and low complication rate. Attention to technique can potentially avoid procedure failure.

Purpose Nearly all literature for predicting tumor grade in astrocytoma and oligodendroglioma pre-dates the molecular classification system. We investigated the association between contrast enhancement, ADC, and rCBV with tumor grade separately for IDH-mutant astrocytomas and molecularly-defined oligodendrogliomas. Methods For this retrospective study, 44 patients with IDH-mutant astrocytomas (WHO grades II, III, or IV) and 39 patients with oligodendrogliomas (IDH-mutant and 1p/19q codeleted) (WHO grade II or III) were enrolled. Two readers independently assessed preoperative MRI for contrast enhancement, ADC, and rCBV. Inter-reader agreement was calculated, and statistical associations between MRI metrics and WHO grade were determined per reader. Results For IDH-mutant astrocytomas, both readers found a stepwise positive association between contrast enhancement and WHO grade (Reader A: OR 7.79 [1.97, 30.80], p = 0.003; Reader B: OR 6.62 [1.70, 25.82], p = 0.006); both readers found that ADC was negatively associated with WHO grade (Reader A: OR 0.74 [0.61, 0.90], p = 0.002); Reader B: OR 0.80 [0.66, 0.96], p = 0.017), and both readers found that rCBV was positively associated with WHO grade (Reader A: OR 2.33 [1.35, 4.00], p = 0.002; Reader B: OR 2.13 [1.30, 3.57], p = 0.003). For oligodendrogliomas, both readers found a positive association between contrast enhancement and WHO grade (Reader A: OR 15.33 [2.56, 91.95], p = 0.003; Reader B: OR 20.00 [2.19, 182.45], p = 0.008), but neither reader found an association between ADC or rCBV and WHO grade. Conclusions Contrast enhancement predicts WHO grade for IDH-mutant astrocytomas and oligodendrogliomas. ADC and rCBV predict WHO grade for IDH-mutant astrocytomas, but not for oligodendrogliomas.

OBJECTIVE: Decompressive craniecturny (DC) is an established optional treatment for malignant hemispheric infarction (MHI). We analyzed relevant clinical factors and computed tomography (CT) measurements in patients with DC for MHI to identify predictors of functional outcome 3-6 months after stroke. METHODS: This study was performed at 2 comprehensive stroke centers. The inclusion criteria required DC for MHI, no additional intraoperative procedures (strokectomy or cerebral ventricular drain placement), and documented functional status 3-6 months after the stroke. We classified functional outcome as acceptable if the modified Rankin Scale score was <5, or as unacceptable if it was 5 or 6 (bedbound and totally dependent on others or death). Multiple logistic regression analyzed relevant clinical factors and multiple perioperative CT measurements to identify predictors of acceptable functional outcome. RESULTS: Of 87 identified consecutive patients, 66 met the inclusion criteria. Acceptable functional outcome occurred in 35 of 66 (53%) patients. Likelihood of acceptable functional outcome decreased significantly with increasing age (OR 0.92, 95% CI 0.82-0.97, P = 0.004) and with increasing post-DC midline brain shift (OR 0.78, 95% CI 0.64-0.96, P = 0.016), and decreased non-significantly with left-sided stroke (OR 0.30, 95% CI 0.08-1.10, P = 0.069) and with increasing craniectomy barrier thickness (OR 0.92, 95% CI 0.85-1.01, P = 0.076). CONCLUSIONS: Patient age and the post-DC midline shift may be useful in prognosticating functional outcome after DC for MHI. Stroke side and craniectomy barrier thickness merit further ideally prospective outcome prediction testing.

Distinguishing tumor progression (TP) vs treatment related necrosis (TN) is critical for clinical management decisions in patients with glioblastoma (GBM). FDG PET is an imaging technique that can provide pathophysiologic and diagnostic data in this clinical setting. We are investigating novel methods using a model corrected blood input function accounting for partial volume averaging and peak fitting cost function to compute parametric maps that reveal more kinetic information. In our study, we use a 4-parameter 3-compartmentmodel on dynamic FDG PET data. To highlight the usefulness of these novel mappings, we created a preliminary prediction algorithm using logistic regression that uses averaged tumor information from these maps. Our preliminary results of tumor segmentation and classification using logistic regression on high resolution parametric PET data are promising in the differentiation of TN from TP in GBM patients based on relevant connections between certain kinetic parameters and the binary prediction outputs.