Lipoma arborescens of the knee: A case report

Lipoma arborescens is a rare and benign intra-articular lesion characterized by a lipomatous proliferation of the synovial membrane, usually affects the knee joint. It presents as an unusual cause of intermittent knee pain and joint effusion. We report a case of lipoma arborescens of the knee in a 23-year-old man that initially resembled inflammatory arthropathy. The diagnosis of Lipoma arborescens was made by magnetic resonance imaging of the knee and confirmed histologically by synovectomy. The purpose of our case is to show the imaging features enabling early diagnosis and appropriate treatment.

Integrated approach of federated learning with transfer learning for classification and diagnosis of brain tumor

Brain tumor classification using MRI images is a crucial yet challenging task in medical imaging. Accurate diagnosis is vital for effective treatment planning but is often hindered by the complex nature of tumor morphology and variations in imaging. Traditional methodologies primarily rely on manual interpretation of MRI images, supplemented by conventional machine learning techniques. These approaches often lack the robustness and scalability needed for precise and automated tumor classification. The major limitations include a high degree of manual intervention, potential for human error, limited ability to handle large datasets, and lack of generalizability to diverse tumor types and imaging conditions.To address these challenges, we propose a federated learning-based deep learning model that leverages the power of Convolutional Neural Networks (CNN) for automated and accurate brain tumor classification. This innovative approach not only emphasizes the use of a modified VGG16 architecture optimized for brain MRI images but also highlights the significance of federated learning and transfer learning in the medical imaging domain. Federated learning enables decentralized model training across multiple clients without compromising data privacy, addressing the critical need for confidentiality in medical data handling. This model architecture benefits from the transfer learning technique by utilizing a pre-trained CNN, which significantly enhances its ability to classify brain tumors accurately by leveraging knowledge gained from vast and diverse datasets.Our model is trained on a diverse dataset combining figshare, SARTAJ, and Br35H datasets, employing a federated learning approach for decentralized, privacy-preserving model training. The adoption of transfer learning further bolsters the model's performance, making it adept at handling the intricate variations in MRI images associated with different types of brain tumors. The model demonstrates high precision (0.99 for glioma, 0.95 for meningioma, 1.00 for no tumor, and 0.98 for pituitary), recall, and F1-scores in classification, outperforming existing methods. The overall accuracy stands at 98%, showcasing the model's efficacy in classifying various tumor types accurately, thus highlighting the transformative potential of federated learning and transfer learning in enhancing brain tumor classification using MRI images.

Advanced AI-driven approach for enhanced brain tumor detection from MRI images utilizing EfficientNetB2 with equalization and homomorphic filtering

Brain tumors pose a significant medical challenge necessitating precise detection and diagnosis, especially in Magnetic resonance imaging(MRI). Current methodologies reliant on traditional image processing and conventional machine learning encounter hurdles in accurately discerning tumor regions within intricate MRI scans, often susceptible to noise and varying image quality. The advent of artificial intelligence (AI) has revolutionized various aspects of healthcare, providing innovative solutions for diagnostics and treatment strategies. This paper introduces a novel AI-driven methodology for brain tumor detection from MRI images, leveraging the EfficientNetB2 deep learning architecture. Our approach incorporates advanced image preprocessing techniques, including image cropping, equalization, and the application of homomorphic filters, to enhance the quality of MRI data for more accurate tumor detection. The proposed model exhibits substantial performance enhancement by demonstrating validation accuracies of 99.83%, 99.75%, and 99.2% on BD-BrainTumor, Brain-tumor-detection, and Brain-MRI-images-for-brain-tumor-detection datasets respectively, this research holds promise for refined clinical diagnostics and patient care, fostering more accurate and reliable brain tumor identification from MRI images. All data is available on Github: https://github.com/muskan258/Brain-Tumor-Detection-from-MRI-Images-Utilizing-EfficientNetB2 ).

Clinical characteristics, course and prognosis of Multiple Sclerosis patients with epilepsy. A case control study: MS and epilepsy

BACKGROUND AND PURPOSE

Although more common than in the general population, seizures are an atypical manifestation of multiple sclerosis (MS) and their pathophysiology is not well understood. This study aims to examine the prevalence, clinical characteristics, brain imaging findings and course of epilepsy, presenting in patients with MS.

METHODS

Observational retrospective study of MS patients evaluated at a single MS reference center in Buenos Aires, Argentina, between 2011 and 2022, focusing on those who developed epilepsy (EMS). Clinical, demographic, and prognostic factors were evaluated and compared to a control group of non-epileptic MS patients (NEMS). To analyze specific epilepsy characteristics, a second control group of patients with non-lesional focal epilepsy (FNLE) was also included.

RESULTS

Twenty-five patients (18 women), were diagnosed with epilepsy, corresponding to a prevalence of 1.95%. Comparison of brain imaging characteristics between EMS and NEMS patients showed brain atrophy (32% vs 6.1%, p<0.01), as well as cortical (26% vs 4%, p=0.03) and juxtacortical lesions (84% vs 55%, p=0.05), were more frequent in EMS patients. However, after multivariate analysis, cortical atrophy was the only variable linked to a significant increase in risk of epilepsy (OR 24, 95%CI=2.3-200, p<0.01). No significant differences in clinical characteristics, disease activity, disability levels, response to disease modified treatment (DMT) or lack of DMT efficacy were observed between MS patients with or without epilepsy. Most patients received anti-seizure medication (ASM), and seizure control was better in EMS than in FNLE patients (92% vs 58%, p=0.022) with no differences found in drug resistance. We did not find predictors of seizure recurrence in the population studied.

CONCLUSION

We observed a lower prevalence of epilepsy in this group of MS patients, compared to other reported cohorts. Although epilepsy seems to have a benign course in MS patients, cortical atrophy appears to be an important contributor to the development of secondary epilepsy in MS patients. Further investigations will be necessary to identify risk factors or biomarkers predicting increased epilepsy risk in MS.

The application value of LAVA-flex sequences in enhanced MRI scans of nasopharyngeal carcinoma: comparison with T1WI-IDEAL

Introduction

Magnetic resonance imaging (MRI) staging scans are critical for the diagnosis and treatment of patients with nasopharyngeal cancer (NPC). We aimed to evaluate the application value of LAVA-Flex and T1WI-IDEAL sequences in MRI staging scans.

Methods

Eighty-four newly diagnosed NPC patients underwent both LAVA-Flex and T1WI-IDEAL sequences during MRI examinations. Two radiologists independently scored the acquisitions of image quality, fat suppression quality, artifacts, vascular and nerve display. The obtained scores were compared using the Wilcoxon signed rank test. According to the signal intensity (SI) measurements, the uniformity of fat suppression, contrast between tumor lesions and subcutaneous fat tissue, and signal-to-noise ratio (SNR) were compared by the paired t-test.

Results

Compared to the T1WI-IDEAL sequence, LAVA-Flex exhibited fewer artifacts (P<0.05), better visualization of nerves and vessels (P<0.05), and performed superior in the fat contrast ratio of the primary lesion and metastatic lymph nodes (0.80 vs. 0.52, 0.81 vs. 0.56, separately, P<0.001). There was no statistically significant difference in overall image quality, tumor signal-to-noise ratio (SNR), muscle SNR, and the detection rate of lesions between the two sequences (P>0.05). T1WI-IDEAL was superior to LAVA-Flex in the evaluation of fat suppression uniformity (P<0.05).

Discussion

LAVA-Flex sequence provides satisfactory image quality and better visualization of nerves and vessels for NPC with shorter scanning times.

Calcific Peritendinitis in the Gluteus Maximus Tendon

BACKGROUND

Calcific tendinitis is classically a painful condition that most commonly affects the rotator cuff, but may infrequently involve other tendons.

CASE REPORT

We discuss a 57-year-old man who presented to the emergency department with a 4-day history of right hip pain, described as the "worst pain in (his) life." The pain was first noticed at night and had progressively worsened. History, physical examination, and initial laboratory workup indicated an inflammatory vs. infectious process. Continued investigations with imaging techniques revealed the source of pain as calcific tendinitis involving the gluteus maximus tendon. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Symptoms of musculoskeletal pain in the emergency department are ubiquitous. In the proper clinical context, the diagnosis of calcific tendinitis, although uncommon, should be considered once emergent conditions are ruled out. Proper imaging techniques will facilitate accurate diagnosis, expedited pain management, and proper outpatient follow-up.

Predictors of successful treatment after transforaminal epidural steroid injections in patients with lumbar disc herniation

BACKGROUND

Epidural steroid injections are common procedures used to treat lumbosacral radicular pain due to lumbar disc herniation (LDH). It is crucial for the clinician to anticipate which patients can benefit from interventional treatment options.

OBJECTIVE

This study aimed to examine the effect of radiological and clinical parameters on lumbar transforaminal epidural steroid injections (TFESI)/local anesthetic injection outcomes in patients with LDH.

METHODS

This study included 286 patients with LDH (146 males and 140 females). All patients received a fluoroscopically guided TFESI (triamcinolone acetonide 40 mg, lidocaine 2%, and 2.5 ml of physiological saline). Patients were evaluated according to radicular pain, the Oswestry Disability Index (ODI) and the Hospital Anxiety and Depression Scale at baseline and 3 months after the injections. Demographic, clinical and magnetic resonance imaging (MRI) findings were recorded to assess the predictive factors for TFESI outcomes. Pfirrmann Grades 1 and 2 were classified as low-grade nerve root compression and Grade 3 was classified as highgrade nerve root compression.

RESULTS

Compared to baseline measurements there were significant improvements in radicular pain, ODI score, Laseque angle, and Schober test scores 3 months after injection. Improvements of at least 50% in radicular pain relief and the ODI functionality index were (n= 214) 82%, (n= 182) 70% respectively at 3 months. Correlation analyses revealed that a shorter duration of symptoms, lowgrade nerve root compression and foraminal/extraforaminal location on MRI findings were associated with a favorable response.

CONCLUSIONS

Lowgrade nerve root compression was a predictor of a favorable response to TFESI.

Layer-by-Layer Polymer Functionalization Improves Nanoparticle Penetration and Glioblastoma Targeting in the Brain

Glioblastoma is characterized by diffuse infiltration into surrounding healthy brain tissues, which makes it challenging to treat. Complete surgical resection is often impossible, and systemically delivered drugs cannot achieve adequate tumor exposure to prevent local recurrence. Convection-enhanced delivery (CED) offers a method for administering therapeutics directly into brain tumor tissue, but its impact has been limited by rapid clearance and off-target cellular uptake. Nanoparticle (NP) encapsulation presents a promising strategy for extending the retention time of locally delivered therapies while specifically targeting glioblastoma cells. However, the brain's extracellular structure poses challenges for NP distribution due to its narrow, tortuous pores and a harsh ionic environment. In this study, we investigated the impact of NP surface chemistry using layer-by-layer (LbL) assembly to design drug carriers for broad spatial distribution in brain tissue and specific glioblastoma cell targeting. We found that poly-l-glutamate and hyaluronate were effective surface chemistries for targeting glioblastoma cells in vitro. Coadsorbing either polymer with a small fraction of PEGylated polyelectrolytes improved the colloidal stability without sacrificing cancer cell selectivity. Following CED in vivo, gadolinium-functionalized LbL NPs enabled MRI visualization and exhibited a distribution volume up to three times larger than liposomes and doubled the retention half-time up to 13.5 days. Flow cytometric analysis of CED-treated murine orthotopic brain tumors indicated greater cancer cell uptake and reduced healthy cell uptake for LbL NPs compared to nonfunctionalized liposomes. The distinct cellular outcomes for different colayered LbL NPs provide opportunities to tailor this modular delivery system for various therapeutic applications.

A case report of longitudinal extensive transverse myelitis: immunotherapy related adverse effect vs. COVID-19 related immunization complications

Background: Transverse myelitis (TM) is a rare, acquired neuro-immunological spinal cord disorder that occurs with rapid onset of motor weakness, sensory deficits with bowel and bladder dysfunction. Patients being treated with immune checkpoint inhibitors (ICIs) for advanced malignancy have a known higher propensity of developing neuro immune complications. With the advent of COVID-19 pandemic there have been reported cases of TM with COVID-19 immunization. The reported infrequency of TM with both of the aforementioned causes makes delineation of the etiology challenging.Methods: We present a patient with metastatic small cell lung cancer (SCLC) on maintenance Atezolizumab immunotherapy who developed longitudinal extensive transverse myelitis (LETM) after administration of second dose of COVID-19 mRNA vaccine one day prior to presenting symptoms of acute paralysis of the lower extremity, sensory loss from chest down with overflow incontinence. A clinical diagnosis of myelopathy was supported by MRI of the spine illustrating enhancing lesions from C7-T7 concerning for LETM.Results: A 5-day course of pulsed methylprednisolone followed by therapeutic plasma exchange for 3 days resulted in only minimal improvement in the neurologic exam with increased strength in his lower extremities while the sensory level remained unchanged.Conclusions: This case demonstrates the complication and symptomatology of TM in the setting of anti-PD-L1 monoclonal antibody with coincidental COVID-19 mRNA vaccine administration. The causal relationship between the vaccine and LETM is difficult to establish. However, the presence of a known inciting factor hints at a possible exaggeration of the existing neuro-inflammatory process.

Redox Properties and in Vivo Magnetic Resonance Imaging of Cyclodextrin-Polynitroxides Contrast Agents

This paper reports the synthesis, characterization and in vivo application of water-soluble supramolecular contrast agents (Mw: 5-5.6 kDa) for MRI obtained from β-cyclodextrin functionalized with different kinds of nitroxide radicals, both with piperidine structure (CD2 and CD3) and with pyrrolidine structure (CD4 and CD5). As to the stability of the radicals in presence of ascorbic acid, CD4 and CD5 have low second order kinetic constants (≤0.05 M-1  s-1 ) compared to CD2 (3.5 M-1  s-1 ) and CD3 (0.73 M-1  s-1 ). Relaxivity (r1 ) measurements on compounds CD3-CD5 were carried out at different magnetic field strength (0.7, 3, 7 and 9.4 T). At 0.7 T, r1 values comprised between 1.5 mM-1  s-1 and 1.9 mM-1  s-1 were found while a significant reduction was observed at higher fields (r1 ≈0.6-0.9 mM-1  s-1 at 9.4 T). Tests in vitro on HEK293 human embryonic kidney cells, L929 mouse fibroblasts and U87 glioblastoma cells indicated that all compounds were non-cytotoxic at concentrations below 1 μmol mL-1 . MRI in vivo was carried out at 9.4 T on glioma-bearing rats using the compounds CD3-CD5. The experiments showed a good lowering of T1 relaxation in tumor with a retention of the contrast for at least 60 mins confirming improved stability also in vivo conditions.

Impact of MRI on target volume definition in head and neck cancer patients

BACKGROUND

Target volume definition for curative radiochemotherapy in head and neck cancer is crucial since the predominant recurrence pattern is local. Additional diagnostic imaging like MRI is increasingly used, yet it is usually hampered by different patient positioning compared to radiotherapy. In this study, we investigated the impact of diagnostic MRI in treatment position for target volume delineation.

METHODS

We prospectively analyzed patients who were suitable and agreed to undergo an MRI in treatment position with immobilization devices prior to radiotherapy planning from 2017 to 2019. Target volume delineation for the primary tumor was first performed using all available information except for the MRI and subsequently with additional consideration of the co-registered MRI. The derived volumes were compared by subjective visual judgment and by quantitative mathematical methods.

RESULTS

Sixteen patients were included and underwent the planning CT, MRI and subsequent definitive radiochemotherapy. In 69% of the patients, there were visually relevant changes to the gross tumor volume (GTV) by use of the MRI. In 44%, the GTV_MRI would not have been covered completely by the planning target volume (PTV) of the CT-only contour. Yet, median Hausdorff und DSI values did not reflect these differences. The 3-year local control rate was 94%.

CONCLUSIONS

Adding a diagnostic MRI in RT treatment position is feasible and results in relevant changes in target volumes in the majority of patients.

3D-Vision-Transformer Stacking Ensemble for Assessing Prostate Cancer Aggressiveness from T2w Images

Vision transformers represent the cutting-edge topic in computer vision and are usually employed on two-dimensional data following a transfer learning approach. In this work, we propose a trained-from-scratch stacking ensemble of 3D-vision transformers to assess prostate cancer aggressiveness from T2-weighted images to help radiologists diagnose this disease without performing a biopsy. We trained 18 3D-vision transformers on T2-weighted axial acquisitions and combined them into two- and three-model stacking ensembles. We defined two metrics for measuring model prediction confidence, and we trained all the ensemble combinations according to a five-fold cross-validation, evaluating their accuracy, confidence in predictions, and calibration. In addition, we optimized the 18 base ViTs and compared the best-performing base and ensemble models by re-training them on a 100-sample bootstrapped training set and evaluating each model on the hold-out test set. We compared the two distributions by calculating the median and the 95% confidence interval and performing a Wilcoxon signed-rank test. The best-performing 3D-vision-transformer stacking ensemble provided state-of-the-art results in terms of area under the receiving operating curve (0.89 [0.61-1]) and exceeded the area under the precision-recall curve of the base model of 22% (p < 0.001). However, it resulted to be less confident in classifying the positive class.

Assessment of brain cancer atlas maps with multimodal imaging features

BACKGROUND

Glioblastoma Multiforme (GBM) is a fast-growing and highly aggressive brain tumor that invades the nearby brain tissue and presents secondary nodular lesions across the whole brain but generally does not spread to distant organs. Without treatment, GBM can result in death in about 6 months. The challenges are known to depend on multiple factors: brain localization, resistance to conventional therapy, disrupted tumor blood supply inhibiting effective drug delivery, complications from peritumoral edema, intracranial hypertension, seizures, and neurotoxicity.

MAIN TEXT

Imaging techniques are routinely used to obtain accurate detections of lesions that localize brain tumors. Especially magnetic resonance imaging (MRI) delivers multimodal images both before and after the administration of contrast, which results in displaying enhancement and describing physiological features as hemodynamic processes. This review considers one possible extension of the use of radiomics in GBM studies, one that recalibrates the analysis of targeted segmentations to the whole organ scale. After identifying critical areas of research, the focus is on illustrating the potential utility of an integrated approach with multimodal imaging, radiomic data processing and brain atlases as the main components. The templates associated with the outcome of straightforward analyses represent promising inference tools able to spatio-temporally inform on the GBM evolution while being generalizable also to other cancers.

CONCLUSIONS

The focus on novel inference strategies applicable to complex cancer systems and based on building radiomic models from multimodal imaging data can be well supported by machine learning and other computational tools potentially able to translate suitably processed information into more accurate patient stratifications and evaluations of treatment efficacy.

The Spinal Cord as Organ of Risk: Assessment for Acute and Subacute Neurological Adverse Effects after Microbeam Radiotherapy in a Rodent Model

Microbeam radiotherapy (MRT), a high dose rate radiotherapy technique using spatial dose fractionation at the micrometre range, has shown a high therapeutic efficacy in vivo in different tumour entities, including lung cancer. We have conducted a toxicity study for the spinal cord as organ of risk during irradiation of a target in the thoracic cavity. In young adult rats, the lower thoracic spinal cord was irradiated over a length of 2 cm with an array of quasi-parallel microbeams of 50 µm width, spaced at a centre-to-centre distance of 400 µm, with MRT peak doses up to 800 Gy. No acute or subacute adverse effects were observed within the first week after irradiation up to MRT peak doses of 400 Gy. No significant differences were seen between irradiated animals and non-irradiated controls in motor function and sensitivity, open field test and somatosensory evoked potentials (SSEP). After irradiation with MRT peak doses of 450-800 Gy, dose-dependent neurologic signs occurred. Provided that long-term studies do not reveal significant morbidity due to late toxicity, an MRT dose of 400 Gy can be considered safe for the spinal cord in the tested beam geometry and field size.

Early and late contrast enhancing lesions after photon radiotherapy for IDH mutated grade 2 diffuse glioma

OBJECTIVE

The interpretation of new enhancing lesions after radiotherapy for diffuse glioma remains a clinical challenge. We sought to characterize and classify new contrast enhancing lesions in a historical multicenter cohort of patients with IDH mutated grade 2 diffuse glioma treated with photon therapy.

METHODS

We reviewed all follow-up MRI's of all patients treated with radiotherapy for histologically confirmed, IDH mutated diffuse grade 2 glioma between 1-1-2007 and 31-12-2018 in two tertiary referral centers. Disease progression (PD) was defined in accordance with the RANO criteria for progressive disease in low grade glioma. Pseudoprogression (psPD) was defined as any transient contrast-enhancing lesion between the end of radiotherapy and PD, or any new contrast-enhancing lesion that remained stable over a period of 12 months in patients who did not exhibit PD.

RESULTS

A total of 860 MRI's of 106 patients were reviewed. psPD was identified in 24 patients (23%) on 76 MRI's. The cumulative incidence of psPD was 13% at 1 year, 22% at 5 years, and 28% at 10 years. The mean of the observed maximal volume of psPD was 2.4cc. The median Dmin in psPD lesions was 50.1 Gy. The presence of an 1p/19q codeletion was associated with an increased risk of psPD (subhazard ratio 2.34, p=0.048). psPD was asymptomatic in 83% of patients.

CONCLUSION

The cumulative incidence of psPD in grade 2 diffuse glioma increases over time. Consensus regarding event definition and statistical analysis is needed for comparisons between series investigating psPD.

Inadequate gonadal replacement in patients with Turner syndrome may result in pituitary volume enlargement

OBJECTIVES

Patients with Turner syndrome need hormone replacement therapy for puberty induction. However, it is not known whether inadequate hormone replacement therapy affects the pituitary.

DESIGN AND PATIENTS

Patients with Turner syndrome (n=35) and healthy control (n=20) (age/gender matched) subjects were included. MRI imaging of the pituitary was used to calculate pituitary volumes. According to the estradiol regimen, patients were divided into two groups; (i) those treated with low-dose conjugated oestrogen (CE, 0.625 mg) and (ii) those treated with combination therapy (ethinyl estradiol+sipropterone acetate; 35 mcg/2 mg). Pituitary measurements were calculated according to pituitary borders and their distances to each other via pituitary MRI.

RESULTS

Pituitary hyperplasia (0.58±0.15 cm3 vs. 0.40±0.17 cm3) was determined in patients with low dose conjugated estrogen compared to the other patients or healthy control subjects (0.42±0.16 cm3) (p=0.005). Serum FSH levels of the patients treated with low dose CE were also higher compared to the patients who received combination therapy (p=0.001).

CONCLUSION

Inadequate hormone replacement therapy can cause devastating effects on the bones and uterine health and disrupts the pituitary structure.

Preganglionic injury of C8 nerve root secondary to shoulder dislocation: Diagnosis based on MRI findings

INTRODUCTION

Traumatic spinal root injury caused by shoulder dislocation may involve the brachial plexus or, in some cases, a single nerve. The degree of severity of the injury depends on many patient-specific factors as well as the mechanism of injury. It is essential to suspect this type of lesion by means of a thorough physical examination in order to have better patient outcomes.

CASE PRESENTATION

We presented the subtle magnetic resonance imaging (MRI) findings in a 35-year-old male with left shoulder trauma and dislocation after falling off a bicycle. He complained of decreased muscle strength and sensitivity in the C8 dermatome. Atrophy of the hypothenar region and flexion deformity of the 4th and 5th digits were noted. Magnetic resonance imaging findings were consistent with a partial preganglionic C8 motor root lesion. We found T2 increased signal intensity and thinning of the intradural segment of the C8 motor nerve root and low signal in the sequence of a multi-echo gradient recalled echo (GRE).

CONCLUSION

MRI is a noninvasive tool that allows a detailed anatomical characterization of the nerves. In brachial plexus injuries, the use of the GRE sequence is useful to identify the lesions, even if they are subtle; however, some lesions may go unnoticed. It is important to note that these patients require an interdisciplinary group to reach a correct diagnosis, which is vital to establish the appropriate treatment and follow-up.

Dopamine and DNA functionalized manganese whitlockite nanocrystals for magnetic resonance imaging and chemo-photothermal therapy of tumors

Multifunctional inorganic nanomaterials have opened new avenues for cancer diagnosis and therapy. However, the difficulty to functionalize them has prevented their wider application, owing to the lack of active groups on their surfaces. Here we report a novel method to functionalize manganese whitlockite (Mn-WH) with polydopamine (PDA) and hairpin DNA (hpDNA) to improve the water stability and anti-cancer effects of Mn-WH nanoparticles (Mn-WH NPs). Compared to WH NPs, the Mn-WH@PDA-hpDNA NPs exhibit better water dispersibility, high drug loading capacity, excellent photothermal performance, stable MRI imaging ability, and outstanding chemo-photothermal synergistic therapeutic potential against tumors. After intratumoral injection in nude mice, the Mn-WH@PDA-hpDNA-DOX NPs promote complete tumor ablation upon exposure to 808 laser-irradiation. The nanoparticles showed no major side effects or toxicity. Thus, these results indicate that the Mn-WH@PDA-hpDNA-DOX NPs have excellent potential as anti-cancer agents, along with excellent magnetic resonance imaging (MRI) capabilities and the reported functionalization approach provides a novel and effective strategy for the surface functionalization of inorganic nanomaterials.

Dry synovitis, a rare entity distinct from juvenile idiopathic arthritis

BACKGROUND

Dry synovitis (DS) is a rare entity as only a few cases have been reported to date. We describe the clinical features, radiological manifestations and course of DS in comparison with rheumatoid factor negative polyarticular juvenile idiopathic arthritis (RFneg-polyJIA).

METHODS

We performed a multicenter retrospective collection of data of DS patients who presented with progressive joint limitations without palpable synovitis, absence of elevated acute phase reactants, negative ANA and RF, and imaging showing joint and/or osteochondral involvement. For comparative purposes, we included a cohort of RF neg-polyJIA patients.

RESULTS

Twelve DS patients, 8F/4 M, with mean age at onset of 6.1 years, were included. Presenting signs comprised delayed motor development, functional limitations and/or progressive stiffness. Clinical examination showed symmetric polyarticular involvement with variable muscular atrophy. MRI showed mild, diffuse synovial involvement, without effusion. With time, signs of progressive osteochondral damage became evident, despite treatment. All patients were treated with low-dose corticosteroids and methotrexate. Anti-TNF agents were prescribed in five. The response was variable with limited joint mobility in 11/12, and need of joint replacement in 2. In comparison with a cohort of RFneg-polyJIA, DS patients presented higher number of joint involved (p = 0.0001) and contractures (p = 0.0001), less swelling (p = 0.0001) and prolonged diagnostic delay (p = 0.0001).

CONCLUSION

DS represents a unique juvenile-onset arthropathy, distinct from polyarticular JIA. Awareness among pediatricians is essential for early recognition and proper treatment. Further studies, including synovial pathology, immunology and genetics may contribute to a better understanding of this rare disorder of childhood.

Preclinical PET and MR Evaluation of 89Zr- and 68Ga-Labeled Nanodiamonds in Mice over Different Time Scales

Nanodiamonds (NDs) have high potential as a drug carrier and in combination with nitrogen vacancies (NV centers) for highly sensitive MR-imaging after hyperpolarization. However, little remains known about their physiological properties in vivo. PET imaging allows further evaluation due to its quantitative properties and high sensitivity. Thus, we aimed to create a preclinical platform for PET and MR evaluation of surface-modified NDs by radiolabeling with both short- and long-lived radiotracers. Serum albumin coated NDs, functionalized with PEG groups and the chelator deferoxamine, were labeled either with zirconium-89 or gallium-68. Their biodistribution was assessed in two different mouse strains. PET scans were performed at various time points up to 7 d after i.v. injection. Anatomical correlation was provided by additional MRI in a subset of animals. PET results were validated by ex vivo quantification of the excised organs using a gamma counter. Radiolabeled NDs accumulated rapidly in the liver and spleen with a slight increase over time, while rapid washout from the blood pool was observed. Significant differences between the investigated radionuclides were only observed for the spleen (1 h). In summary, we successfully created a preclinical PET and MR imaging platform for the evaluation of the biodistribution of NDs over different time scales.

Comparison of computed tomography and 3D magnetic resonance imaging in evaluating glenohumeral instability bone loss

BACKGROUND

To determine whether the addition of 3-dimensional (3D) magnetic resonance imaging (MRI) to standard MRI sequences is comparable to 3D computed tomographic (CT) scan evaluation of glenoid and humeral bone loss in glenohumeral instability.

METHODS

Eighteen patients who presented with glenohumeral instability were prospectively enrolled and received both MRI and CT within 1 week of each other. The MRI included an additional sequence (volumetric interpolated breath-hold examination [VIBE]) that underwent postprocessing for reformations. The addition of a VIBE protocol, on average, is an additional 4-4.5 minutes in the scanner. CT data also underwent 3D postprocessing, and therefore each patient had 4 imaging modalities (2D CT, 2D MRI, 3D CT reformats, and 3D MRI reformats). Each sequence underwent the following measurements from 2 separate reviewers: glenoid defect, glenoid defect percentage, humeral defect, humeral defect percentage, and evaluation of glenoid track and version. Paired t tests were used to assess differences between imaging modalities and χ² for glenoid track. Intra- and interobserver reliability were evaluated. Bland-Altman tests were also performed to assess the agreement between CT and MRI. In addition, we determined the cost of each imaging modality at our institution.

RESULTS

3D MRI measurements for glenoid and humeral bone loss measurements were comparable to 3D CT (Table 1). There were no significant differences for glenoid defect size and percentage, or humeral defect size and percentage (P > .05) (Table 2). Bland-Altman analysis demonstrated strong agreement, with small measurement errors for 3D CT and 3D MRI percentage glenoid bone loss. There was also no difference in evaluation for determining on vs. off track between any of the imaging modalities. Inter- and intrarater reliability was good to excellent for all CT and MRI measurements (r ≥ 0.7).

CONCLUSION

3D MRI measurements for bone loss in glenohumeral instability through use of VIBE sequence were equivalent to 3D CT. At our institution, undergoing MRI with 3D reconstruction was 1.67 times cheaper than MRI and CT with 3D reconstructions. 3D MRI may be a useful adjuvant to standard MRI sequences to allow concurrent soft tissue and accurate assessment of glenoid and humeral bone loss in glenohumeral instability.

[Study on safe depth of needling at acupoints of kidney regions based on MRI imaging]

OBJECTIVE

To measure the dangerous depth and the effective safe depth of needling at acupoints of kidney regions based on MRI imaging, and to provide the imaging support for clinical practice.

METHODS

The abdominal enhanced T1 MRI imaging of horizontal plane of 61 healthy subjects was included, the anatomical structure of bilateral Weishu (BL 21), Sanjiaoshu (BL 22), Shenshu (BL 23), Weicang (BL 50), Huangmen (BL 51) and Zhishi (BL 52) was analyzed, and the dangerous depth and effective safe depth of perpendicular and oblique needling were measured between the left and right sides and subjects with different body sizes.

RESULTS

There were no significant differences between dangerous depth and effective safe depth of perpendicular and oblique needling at bilateral acupoints of kidney region (P>0.05). The dangerous depth and effective safe depth of perpendicular and oblique needling at bilateral acupoints of kidney region in the moderate group were larger than the underweight group (P<0.05), while those in the overweight group were larger than the moderate group and the underweight group (P<0.05).

CONCLUSION

The safe depth of needling at acupoints of kidney region is related to body size, for moderate weight and overweight patients, the needling depth could be increased for better efficacy, while for underweight patients, the recommend direction and depth of needling should be restricted to avoid acupuncture accident.

Rates of MRI simulator utilisation in a tertiary cancer therapy centre

Magnetic resonance imaging (MRI) is increasingly being integrated into the radiation oncology workflow, due to its improved soft tissue contrast without additional exposure to ionising radiation. A review of MRI utilisation according to evidence based departmental guidelines was performed. Guideline utilisation rates were calculated to be 50% (true utilisation rate was 46%) of all new cancer patients treated with adjuvant or curative intent, excluding simple skin and breast cancer patients. Guideline utilisation rates were highest in the lower gastrointestinal and gynaecological subsites, with the lowest being in the upper gastrointestinal and thorax subsites. Head and neck (38% vs 45%) and CNS (46% vs 67%) cancers had the largest discrepancy between true and guideline utilisation rates due to unnamed reasons and non-contemporaneous diagnostic imaging respectively. This report outlines approximate MRI utilisation rates in a tertiary radiation oncology service and may help guide planning for future departments contemplating installation of an MRI simulator.

Extrusion, meniscal signal change, loss of shape, synovitis and bone marrow oedema are reliable scoring parameters to assess MRI appearance post meniscal transplant

PURPOSE

Meniscal allograft transplantation (MAT) has shown good promise in restoring normal knee joint biomechanics in a meniscal deficient patient. However, MRI appearance of the meniscal allograft is often questioned and raises concerns of its viability and function. This paper aims to introduce and validate a new scoring system for MAT MRI appearance at 12 months [MRI appearance in Meniscal Transplant Score (MIMS)], using key changes such as extrusion, meniscal signal change, loss of shape, synovitis and bone marrow oedema.

METHODS

A retrospective analysis of 10 patients from a single surgeon series was conducted. All MAT were performed with soft tissue fixation technique. MRI was performed at 12 months post-transplant with two independent consultant musculoskeletal radiologists and one experienced meniscal transplant surgeon scoring the images obtained. Interobserver agreement and intraclass correlation were measured.

RESULTS

Interobserver agreement between examiners on individual features of the MIMS was superior for tibial bone oedema, substantial for meniscal extrusion and femoral bone oedema, moderate for meniscal shape and synovitis, and fair for meniscal signal changes. Absolute agreement between raters found good reliability (ICC = 0.774; 95% 0.359, 0.960) for single measures and excellent reliability (ICC = 0.911; 95% 0.627, 0.986) for average measures.

CONCLUSION

MIMS is a reliable method of evaluating the meniscal allograft transplant 12 months post-transplant. Further research with larger MAT cohort groups and patient reported outcome measures may be helpful to correlate its clinical significance and guide further management.

LEVEL OF EVIDENCE

Level III.

Quantitative Detection of In Vivo Aggregation Degree for Enhanced M2 Macrophage MR Imaging

In situ self-assembly in vivo can be used in the enhanced diagnosis and therapy of major diseases such as cancer and bacterial infections on the basis of an assembly/aggregation-induced-retention (AIR) effect. However, the aggregation degree (α_agg) is a significant parameter for determining the delivery efficiency to lesions in a complex physiological environment and a real-time quantitative calculation of the aggregation degree in vivo is still a great challenge. Here, we developed a magnetic resonance imaging (MRI) method for sensitive and quantitative calculation of α_agg with a detection limit of 10^-4 M and a bioactivated in vivo assembly (BIVA) magnetic resonance (MR) probe was optimized for enhanced T₁-weighted MR imaging of M2 macrophages in tumors. Our MRI quantitative calculation method had a high fitting degree (R² = 0.987) with the gold standard fluorescence (FL) method. On the basis of the BIVA mechanism of CD206 active targeting and cathepsin B specific tailoring to induce an in situ nanofiber assembly, our optimized BIVA probe exhibited a high intracellular aggregation degree of over 70% and a high in vivo α_agg value of over 55%. Finally, the aggregation-enhanced T₁ MR signal and the AIR effect both contributed to enhanced T₁-weighted MR imaging of M2 macrophages in triple-negative breast cancer. We believe that our α_agg real-time quantitative calculation method of MRI will help to further screen and optimize the in vivo enhanced imaging and treatment of the BIVA drug.

Multiomics Analysis of Structural Magnetic Resonance Imaging of the Brain and Cerebrospinal Fluid Metabolomics in Cognitively Normal and Impaired Adults

INTRODUCTION

Integrating brain imaging with large scale omics data may identify novel mechanisms of mild cognitive impairment (MCI) and early Alzheimer's disease (AD). We integrated and analyzed brain magnetic resonance imaging (MRI) with cerebrospinal fluid (CSF) metabolomics to elucidate metabolic mechanisms and create a "metabolic map" of the brain in prodromal AD.

METHODS

In 145 subjects (85 cognitively normal controls and 60 with MCI), we derived voxel-wise gray matter volume via whole-brain structural MRI and conducted high-resolution untargeted metabolomics on CSF. Using a data-driven approach consisting of partial least squares discriminant analysis, a multiomics network clustering algorithm, and metabolic pathway analysis, we described dysregulated metabolic pathways in CSF mapped to brain regions associated with MCI in our cohort.

RESULTS

The multiomics network algorithm clustered metabolites with contiguous imaging voxels into seven distinct communities corresponding to the following brain regions: hippocampus/parahippocampal gyrus (three distinct clusters), thalamus, posterior thalamus, parietal cortex, and occipital lobe. Metabolic pathway analysis indicated dysregulated metabolic activity in the urea cycle, and many amino acids (arginine, histidine, lysine, glycine, tryptophan, methionine, valine, glutamate, beta-alanine, and purine) was significantly associated with those regions (P < 0.05).

CONCLUSION

By integrating CSF metabolomics data with structural MRI data, we linked specific AD-susceptible brain regions to disrupted metabolic pathways involving nitrogen excretion and amino acid metabolism critical for cognitive function. Our findings and analytical approach may extend drug and biomarker research toward more multiomics approaches.

Magnetic Resonance Imaging of the Knee in the Presence of Bridging External Fixation: A Comparative Experimental Evaluation of Four External Fixators, Including Dolphix®

Performing MR investigation on patients instrumented with external fixators is still controversial. The aim of this study is to evaluate the quality of MR imaging of the knee structures in the presence of bridging external fixators. Different cadaveric lower limbs were instrumented with the MR-conditional external fixators Hofmann III (Stryker, Kalamazoo, MI, USA), Large external Fixator (DePuy Synthes, Raynham, MA, USA), XtraFix (Zymmer, Warsaw, IN, USA) and a newer implant of Ketron Peek CA30 and ERGAL 7075 pins, Dolphix^®, (Citieffe, Bologna, Italy). The specimens were MR scanned before and after the instrumentation. The images were subjectively judged by a pool of blinded radiologists and then quantitatively evaluated calculating signal intensity, signal to noise and contrast to noise in the five regions of interest. The area of distortion due to the presence of metallic pins was calculated. All the images were considered equally useful for diagnosis with no differences between devices (p > 0.05). Only few differences in the quantification of images have been detected between groups while the presence of metallic components was the main limit of the procedure. The mean length of the radius of the area of distortion of the pins were 53.17 ± 8.19 mm, 45.07 ± 4.33 mm, 17 ± 5.4 mm and 37.12 ± 10.17 mm per pins provided by Zimmer, Synthes, Citieffe and Stryker, respectively (p = 0.041). The implant of Ketron Peek CA30 and ERGAL 7075 pins showed the smallest distortion area.

Analysis of the paraspinal muscle morphology of the lumbar spine using a convolutional neural network (CNN)

PURPOSE

This single-center study aimed to develop a convolutional neural network to segment multiple consecutive axial magnetic resonance imaging (MRI) slices of the lumbar spinal muscles of patients with lower back pain and automatically classify fatty muscle degeneration.

METHODS

We developed a fully connected deep convolutional neural network (CNN) with a pre-trained U-Net model trained on a dataset of 3,650 axial T2-weighted MRI images from 100 patients with lower back pain. We included all qualities of MRI; the exclusion criteria were fractures, tumors, infection, or spine implants. The training was performed using k-fold cross-validation (k = 10), and performance was evaluated using the dice similarity coefficient (DSC) and cross-sectional area error (CSA error). For clinical correlation, we used a simplified Goutallier classification (SGC) system with three classes.

RESULTS

The mean DSC was high for overall muscle (0.91) and muscle tissue segmentation (0.83) but showed deficiencies in fatty tissue segmentation (0.51). The CSA error was small for the overall muscle area of 8.42%, and fatty tissue segmentation showed a high mean CSA error of 40.74%. The SGC classification was correctly predicted in 75% of the patients.

CONCLUSION

Our fully connected CNN segmented overall muscle and muscle tissue with high precision and recall, as well as good DSC values. The mean predicted SGC values of all available patient axial slices showed promising results. With an overall Error of 25%, further development is needed for clinical implementation. Larger datasets and training of other model architectures are required to segment fatty tissue more accurately.

Case of fatal eastern equine encephalitis

Eastern Equine Encephalitis (EEE) is a rare and very serious arbovirus that is transmitted to humans through the bite of infected mosquitoes. When symptomatic, patients with this condition are typically seriously ill and the fatality rate is high. We present a fatal case of EEE that exhibited classic symptoms and findings. Included are high quality MRI images that show the classic radiographic findings of this infection. In addition to confirmatory laboratory findings, the case report includes pathologic specimens from brain tissue obtained at autopsy. Perhaps due to climate change and human encroachment on mosquito habitat, there is a westward spread of EEE in the United States.

Isolated primary spinal epidural hydatid cyst in a child with progressive paraparesis

BACKGROUND

Primary spinal hydatid cyst is a rare but serious condition which occurs in about 1% of patients with hydatid disease. This disease may result in severe spinal cord compression presenting with various neurological deficits.

CASE REPORT

A 3-year-old boy was referred to our center with progressive weakness of lower limbs, frequency, and urinary incontinence. His parents did not report back pain during child's illness. Lumbar magnetic resonance imaging (MRI) revealed an extradural well-defined thin-walled cystic lesion at L4 to S3 vertebral levels without enhancement. The cyst had compressed the thecal sac associated with bone scalloping of vertebral bodies and posterior elements. Osteoplastic laminectomy of L4-L5 and laminectomy of S1-S3 was done. Intraoperative and histopathological findings indicated an epidural hydatid cyst.

CONCLUSION

Although spinal hydatid cysts are rare but might be considered in the differential diagnosis of any patient with signs and symptoms of spinal cord compression. The pathophysiology, clinical manifestations, epidemiology, diagnosis, and surgical treatment of extradural hydatid cyst are discussed.

Alterations in Intracardiac Flow Patterns Affect Mitral Leaflets Dynamics in a Model of Ischemic Mitral Regurgitation

PURPOSE

This study was to evaluate the effects of ischemic mitral regurgitation (IMR) on vortex formation and leaflet dynamics using an established porcine infarct model of IMR.

METHODS

Using direct coronary ligation, five animals were subjected to a posterolateral myocardial infarction (MI) followed by an MRI at 12-weeks post MI. MR imaging consisted of 4D time-resolved left ventricular (LV) flow, full coverage 2D LV cine, and high resolution 2D cine of mitral valve dynamics. Five additional naïve animals underwent identical imaging protocols to serve as controls. Image analysis was performed to obtain mitral transvalvular flows as well as LV volumes throughout the cardiac cycle. In addition, anterior to posterior mid-leaflet tip distances were measured throughout the cardiac cycle for determination of temporal leaflet dynamics.

RESULTS

It was found IMR caused asymmetric vortex ring formation with the anterior vortex having a lower vorticity relative to its posterior counterpart. In contrast, normal ventricles create symmetric and tightly curled vortices in the basal chamber just underneath the mitral leaflets which conserve kinetic energy and aid in effective ejection. IMR animals were also evaluated for leaflet separation and were found to have a greater leaflet opening and achieved peak vorticity and peak leaflet opening later than control animals.

CONCLUSION

In conclusion, this study shows the effects that altered vortex formation, due to IMR, can have on ventricular filling and leaflet dynamics. These findings have important implications for understanding blood flow through the dilated heart and how ring annuloplasty and volume reduction interventions may influence mitral valve dynamics.

The cancer therapy materialization by theranostic nanoparticles based on gold doped iron oxide under electromagnetic field amplification

The harnessing of the cancer X-ray radiation therapy by gold-decorated Fe₃O₄ theranostic nanoparticles (Au-Fe₃O₄ NPs) under electromagnetic field was articulated. The applied electromagnetic field could assemble the NPs inside cell in oriented field direction and enhance the local irradiation dose inside cell. By materializing NPs, the absorption of the energy exposed by X-ray radiation under electromagnetic field was restricted. The cytotoxic properties of the Au-Fe₃O₄ NPs were assessed using MTT assay in L929, HeLa and PC3 cell lines under radiation and dark conditions. The efficiency of the Au-Fe₃O₄ NPs under 2 Gy dose radiations was higher than 6 Gy radiations in untreated cells. The in vitro measurements showed that under electromagnetic field and X-ray radiation therapy with Au-Fe₃O₄ NPs, around 90% of the cancer cells population was annihilated. The in vivo measurements indicated that the tumor shape and size under X-ray with Au-Fe₃O₄ NPs after 3 weeks were efficiently deteriorated.

Bevacizumab for radiation necrosis following radiotherapy of brain metastatic disease: a systematic review & meta-analysis

Background

Radiotherapy is the mainstay of brain metastasis (BM) management. Radiation necrosis (RN) is a serious complication of radiotherapy. Bevacizumab (BV), an anti-vascular endothelial growth factor monoclonal antibody, has been increasingly used for RN treatment. We systematically reviewed the medical literature for studies reporting the efficacy and safety of bevacizumab for treatment of RN in BM patients.

Materials and methods

PubMed, Medline, EMBASE, and Cochrane library were searched with various search keywords such as “bevacizumab” OR “anti-VEGF monoclonal antibody” AND “radiation necrosis” OR “radiation-induced brain necrosis” OR “RN” OR “RBN” AND “Brain metastases” OR “BM” until 1st Aug 2020. Studies reporting the efficacy and safety of BV treatment for BM patients with RN were retrieved. Study selection and data extraction were carried out by independent investigators. Open Meta Analyst software was used as a random effects model for meta-analysis to obtain mean reduction rates.

Results

Two prospective, seven retrospective, and three case report studies involving 89 patients with RN treated with BV were included in this systematic review and meta-analysis. In total, 83 (93%) patients had a recorded radiographic response to BV therapy, and six (6.7%) had experienced progressive disease. Seven studies (n = 73) reported mean volume reductions on gadolinium-enhanced T1 (mean: 47.03%, +/− 24.4) and T2-weighted fluid-attenuated inversion recovery (FLAIR) MRI images (mean: 61.9%, +/− 23.3). Pooling together the T1 and T2 MRI reduction rates by random effects model revealed a mean of 48.58 (95% CI: 38.32–58.85) for T1 reduction rate and 62.017 (95% CI: 52.235–71.799) for T2W imaging studies. Eighty-five patients presented with neurological symptoms. After BV treatment, nine (10%) had stable symptoms, 39 (48%) had improved, and 34 (40%) patients had complete resolution of their symptoms. Individual patient data was available for 54 patients. Dexamethasone discontinuation or reduction in dosage was observed in 30 (97%) of 31 patients who had recorded dosage before and after BV treatment. Side effects were mild.

Conclusions

Bevacizumab presents a promising treatment strategy for patients with RN and brain metastatic disease. Radiographic response and clinical improvement was observed without any serious adverse events. Further class I evidence would be required to establish a bevacizumab recommendation in this group of patients.

Differential early subcortical involvement in genetic FTD within the GENFI cohort

BACKGROUND

Studies have previously shown evidence for presymptomatic cortical atrophy in genetic FTD. Whilst initial investigations have also identified early deep grey matter volume loss, little is known about the extent of subcortical involvement, particularly within subregions, and how this differs between genetic groups.

METHODS

480 mutation carriers from the Genetic FTD Initiative (GENFI) were included (198 GRN, 202 C9orf72, 80 MAPT), together with 298 non-carrier cognitively normal controls. Cortical and subcortical volumes of interest were generated using automated parcellation methods on volumetric 3 T T1-weighted MRI scans. Mutation carriers were divided into three disease stages based on their global CDR® plus NACC FTLD score: asymptomatic (0), possibly or mildly symptomatic (0.5) and fully symptomatic (1 or more).

RESULTS

In all three groups, subcortical involvement was seen at the CDR 0.5 stage prior to phenoconversion, whereas in the C9orf72 and MAPT mutation carriers there was also involvement at the CDR 0 stage. In the C9orf72 expansion carriers the earliest volume changes were in thalamic subnuclei (particularly pulvinar and lateral geniculate, 9-10%) cerebellum (lobules VIIa-Crus II and VIIIb, 2-3%), hippocampus (particularly presubiculum and CA1, 2-3%), amygdala (all subregions, 2-6%) and hypothalamus (superior tuberal region, 1%). In MAPT mutation carriers changes were seen at CDR 0 in the hippocampus (subiculum, presubiculum and tail, 3-4%) and amygdala (accessory basal and superficial nuclei, 2-4%). GRN mutation carriers showed subcortical differences at CDR 0.5 in the presubiculum of the hippocampus (8%).

CONCLUSIONS

C9orf72 expansion carriers show the earliest and most widespread changes including the thalamus, basal ganglia and medial temporal lobe. By investigating individual subregions, changes can also be seen at CDR 0 in MAPT mutation carriers within the limbic system. Our results suggest that subcortical brain volumes may be used as markers of neurodegeneration even prior to the onset of prodromal symptoms.

Quantitative measurements of prostatic zones by MRI and their dependence on prostate size: possible clinical implications in prostate cancer

AIM

Many studies support an inverse relationship between benign prostate hypertrophy (BPH) size and incidence of prostate cancer (PCa), but the causal link between these conditions is poorly understood. Recent studies suggest that a growing transition zone (TZ) in the prostate may induce pressure on the outer peripheral zone (PZ), leading to atrophy of the glandular tissue where PCa often originates, providing a possible explanation for this interaction. To further investigate this phenomenon, our pilot study uses magnetic resonance imaging (MRI) to examine quantitative zonal changes in a consecutive cohort of prostates.

METHODS

MRI scans of male patients [n = 204, 61.57 ± 13.90 years, average body mass index (BMI) 29.05 kg/m2] with various prostate sizes were analyzed statistically to identify possible associations between prostate parameters, such as total prostate volume (TPV) and peripheral zone thickness (PZT).

RESULTS

TPV and PZT demonstrated a weak, inverse correlation (r = -0.21, p = 0.002). However, when examining the plotted data, the relationship between TPV and PZT was significantly different when the cohort was divided into two groups; lower TPV: ⩽87.5 ml (n = 188, TPV x- = 36.01 ± 18.18 ml), and higher TPV: >87.5 ml (n = 17, TPV x- = 125.69 ± 41.13 ml). Average PZT differed significantly between these groups (z = -3.5554, p = 0.0004).

CONCLUSIONS

PZT was significantly different for patients with lower versus higher TPVs, suggesting that, above a certain point of BPH growth, the PZ is unable to withstand pressure from an expanding TZ, supporting the notion that growing BPH causes compression of the PZ glandular tissue, and, therefore, BPH may be protective against PCa.

Normal appearing brain white matter changes in relapsing multiple sclerosis: Texture image and classification analysis in serial MRI scans

OBJECTIVE

There is a clinical interest in identifying normal appearing white matter (NAWM) areas in brain T2-weighted (T₂W) MRI scans in multiple sclerosis (MS) subjects. These areas are susceptible to disease development and areas need to be studied in order to find potential associations between texture feature changes and disease progression.

METHODS

The subjects investigated had a first demyelinating event (Clinically Isolated Syndrome-CIS) at baseline (Time₀), and the NAWM₀ (i.e. NAWM at Time₀) of the brain tissue was subsequently converted to demyelinating plaques (as evaluated in a follow up MRI at Time_6-12). 38 untreated subjects that had developed a CIS, had brain MRI scans within an interval of 6-12 months (Time_6-12 at follow-up). An experienced MS neurologist manually delineated the demyelinating lesions at Time₀ (L₀) and at Time_6-12 (L_6-12). Areas in the Time_6-12 MRI scans, where new lesions had been developed, were mapped back to their corresponding NAWM areas on the Time₀ MR scans (ROIS₀). In addition, contralateral ROIs of similar size and shape were segmented on the same images at Time₀ (ROIS_C0) to form an intra-subject control group. Following that, texture features were extracted from all prescribed areas and MS lesions.

RESULTS

Texture features were used as input into Support Vector Machine (SVM) models to differentiate between the following: NAWM₀ vs ROIS_C0, NAWM₀ vs NAWM_6-12, NAWM₀ vs L₀, NAWM_6-12 vs L_6-12, ROIS₀ vs L₀, ROIS₀ vs L_6-12 and ROIS₀ vs ROIS_C0, where the corresponding % correct classifications scores were 89%, 95%, 98%, 92%, 85%, 90% and 65% respectively.

CONCLUSIONS

Texture features may provide complementary information for following up the development and progression of MS disease. Future work will investigate the proposed method on more subjects.

Staging of T2 and T3 nasopharyngeal carcinoma: Proposed modifications for improving the current AJCC staging system

Objectives

We aimed to reconstitute T2 and T3 stage classification in nasopharyngeal carcinoma (NPC) cases and verify its utility in clinical settings.

Materials and Methods

We enrolled 792 NPC patients. Cox proportional hazards model was used to compare the effect sizes (hazard ratio [HR]) of the cranial structure invasion on survival and select the structures for up‐staging or downstaging T2 and T3 NPC. The samples were reclassified and the survival curves for T2 and T3 stages were analyzed. The proposed new staging system was validated on an external sample (n = 433).

Results

Thirteen cranial structures were examined. American Joint Committee on Cancer (AJCC) T3 stage patients with the invasion of the base of the sphenoid (HR = 2.58, 95% CI = 1.16‐5.77) or base of the pterygoid (HR = 2.00, 95% CI = 0.84‐4.77) had significantly lower hazard ratios than T2 stage patients with the invasion of soft tissues in the bilateral parapharyngeal space (HR = 5.26, 95% CI = 2.02‐13.68) and single/bilateral carotid sheath (HR = 7.78, 95% CI = 3.06‐19.76). T3 stage with the invasion of the above‐mentioned bones was reclassified as T2, and T2 stage with the invasion of the above‐mentioned soft‐tissue structures was reclassified as T3. Survival analysis showed a significant difference between the reclassified T2 and T3 stages (P < 0.001). The results were replicated in the validation samples.

Conclusion

The proposed staging system for defining T2 and T3 stage NPC appears to be superior to the AJCC 8th edition. It could improve prognosis and optimize the treatment selection.

Ethmoidal meningoencephalocele in a C57BL/6J mouse

An otherwise healthy two-month-old female C57BL/6J mouse presented with a left-sided head tilt. Differential diagnoses included idiopathic necrotizing arteritis, bacterial otitis media/interna (Pasteurella pneumotropica, Pseudomonas aeruginosa, Streptococcus sp., Mycoplasma pulmonis and Burkholderia gladioli), encephalitis, an abscess, neoplasia, a congenital malformation and an accidental or iatrogenic head trauma. Magnetic resonance imaging (MRI) revealed a large space-occupying right olfactory lobe intra-axial lesion with severe secondary left-sided subfalcine herniation. Following imaging, the animal was euthanized due to poor prognosis. Histopathologic examination revealed a unilateral, full-thickness bone defect at the base of the cribriform plate and nasal conchae dysplasia, resulting in the herniation of the olfactory bulb into the nasal cavity. There was also a left midline-shift of the frontal cortex and moderate catarrhal sinusitis in the left mandibular sinus. The MRI and histopathologic changes are consistent with a congenital malformation of the nasal cavity and frontal aspect of the skull known as an ethmoidal meningoencephalocele. Encephaloceles are rare abnormalities caused by herniation of contents of the brain through a defect in the skull which occur due to disruption of the neural tube closure at the level anterior neuropore or secondary to trauma, surgical complications, cleft palate or increased intracranial pressure. The etiology is incompletely understood but hypotheses include genetics, vitamin deficiency, teratogens, infectious agents and environmental factors. Ethmoidal encephaloceles have been reported in multiple species including humans but have not been reported previously in mice. There are multiple models for spontaneous and induced craniofacial malformation in mice, but none described for ethmoidal encephaloceles.

Complete third nerve palsy as a presenting feature of an interpeduncular lipoma

BACKGROUND

Intracranial lipomas are rare, benign lesions, of congenital origin commonly found incidentally on imaging studies.

METHODS

We describe a case of interpeduncular lipoma in an 18 year-old female presenting with a painful left complete oculomotor (IIIrd) nerve palsy and associated headache, which to the best of our knowledge has not been reported in an adult patient.

RESULTS

Following eye patching and steroid treatment, at 6-week follow-up the patient's pain had significantly improved however the complete IIIrd nerve palsy remained.

CONCLUSIONS

Evidence suggests improvement will occur regardless with conservative management independent of radiological changes to the lipoma.

Tumor-Specific Endogenous FeII-Activated, MRI-Guided Self-Targeting Gadolinium-Coordinated Theranostic Nanoplatforms for Amplification of ROS and Enhanced Chemodynamic Chemotherapy

Low drug payload and lack of tumor-targeting for chemodynamic therapy (CDT) result in an insufficient reactive oxygen species (ROS) generation, which seriously hinders its further clinical application. Therefore, how to improve the drug payload and tumor targeting for amplification of ROS and combine it with chemotherapy has been a huge challenge in CDT. Herein, methotrexate (MTX), gadolinium (Gd), and artesunate (ASA) were used as theranostic building blocks to be coordinately assembled into tumor-specific endogenous Fe^II-activated and magnetic resonance imaging (MRI)-guided self-targeting carrier-free nanoplatforms (NPs) for amplification of ROS and enhanced chemodynamic chemotherapy. The obtained ASA-MTX-Gd^III NPs exhibited extremely high drug payload (∼96 wt %), excellent physiological stability, long circulating ability (half-time: ∼12 h), and outstanding tumor accumulation. Moreover, ASA-MTX-Gd^III NPs could be specifically uptaken by tumor cells via folate (FA) receptors and subsequently be disassembled via lysosomal acidity-induced coordination breakage, resulting in drug burst release. Most strikingly, the produced ASA could be catalyzed by tumor-specific overexpressed endogenous Fe^II ions to generate sufficient ROS for enhancing the main chemodynamic efficacy, which could exert a synergistic effect with the assistant chemotherapy of MTX. Interestingly, ASA-MTX-Gd^III NPs caused a lower ROS generation and toxicity on normal cell lines that seldom expressed endogenous Fe^II ions. Under MRI guidance with assistance of self-targeting, significantly superior synergistic tumor therapy was performed on FA receptor-overexpressed tumor-bearing mice with a higher ROS generation and an almost complete elimination of tumor. This work highlights ASA-MTX-Gd^III NPs as an efficient chemodynamic-chemotherapeutic agent for MRI imaging and tumor theranostics.

Deep Learning Techniques for Automatic Detection of Embryonic Neurodevelopmental Disorders

The increasing rates of neurodevelopmental disorders (NDs) are threatening pregnant women, parents, and clinicians caring for healthy infants and children. NDs can initially start through embryonic development due to several reasons. Up to three in 1000 pregnant women have embryos with brain defects; hence, the primitive detection of embryonic neurodevelopmental disorders (ENDs) is necessary. Related work done for embryonic ND classification is very limited and is based on conventional machine learning (ML) methods for feature extraction and classification processes. Feature extraction of these methods is handcrafted and has several drawbacks. Deep learning methods have the ability to deduce an optimum demonstration from the raw images without image enhancement, segmentation, and feature extraction processes, leading to an effective classification process. This article proposes a new framework based on deep learning methods for the detection of END. To the best of our knowledge, this is the first study that uses deep learning techniques for detecting END. The framework consists of four stages which are transfer learning, deep feature extraction, feature reduction, and classification. The framework depends on feature fusion. The results showed that the proposed framework was capable of identifying END from embryonic MRI images of various gestational ages. To verify the efficiency of the proposed framework, the results were compared with related work that used embryonic images. The performance of the proposed framework was competitive. This means that the proposed framework can be successively used for detecting END.

Primarily depression manifestation of Wilson's disease-Case report

Wilson's disease is an inherited autosomal-recessive disorder of biliary copper excretion. It is characterized by hepatic, neurological and ophthalmic manifestations related to the accumulation of copper in the liver, the lenticular nuclei of brain and cornea. The authors present the case of a 29-year-old female with primarily depression manifestation of Wilson's disease. The patient also reported agitation, difficulties with concentration, slowdown of speech, and stuttering. In magnetic resonance imaging, in putamen, the globus pallidus, claustrum, the heads of caudate nucleus and thalamus areas demonstrated the increased signal in T2. A high copper content was obtained in daily urine collection and reduced level in serum. Similarly, ceruloplasmin level was decreased. Despite the antidepressant treatment with venlafaxine, no improvement was observed. Within a week of psychomotor slowdown, symptoms such as Parkinson's syndrome appeared. Due to the rapid progression of the disease symptoms, the patient was referred for further treatment at a specialistic center. After six month, despite the treatment, the progress of disease was so advanced that patient was transferred to the hospice. Two weeks later patient died. Wilson's disease might be consider in differential diagnosis of depression in young patients, especially if they present additional extrapyramidal symptoms and unspecific changes in magnetic resonance imaging.

Using mathematics in MRI data management for glioma assesment

Our aim is to review the mathematical tools usefulness in MR data management for glioma diagnosis and treatment optimization. MRI does not give access to organs variations in hours or days. However a lot of multiparametric data are generated. Mathematics could help to override this paradox, the aim of this article is to show how. We first make a review on mathematical modelling using equations. Afterwards we present statistical analysis. We provide detailed examples in both sections. We finally conclude, giving some clues on in silico models.

Rationale and Design of the Hamburg City Health Study

The Hamburg City Health Study (HCHS) is a large, prospective, long-term, population-based cohort study and a unique research platform and network to obtain substantial knowledge about several important risk and prognostic factors in major chronic diseases. A random sample of 45,000 participants between 45 and 74 years of age from the general population of Hamburg, Germany, are taking part in an extensive baseline assessment at one dedicated study center. Participants undergo 13 validated and 5 novel examinations primarily targeting major organ system function and structures including extensive imaging examinations. The protocol includes validate self-reports via questionnaires regarding lifestyle and environmental conditions, dietary habits, physical condition and activity, sexual dysfunction, professional life, psychosocial context and burden, quality of life, digital media use, occupational, medical and family history as well as healthcare utilization. The assessment is completed by genomic and proteomic characterization. Beyond the identification of classical risk factors for major chronic diseases and survivorship, the core intention is to gather valid prevalence and incidence, and to develop complex models predicting health outcomes based on a multitude of examination data, imaging, biomarker, psychosocial and behavioral assessments. Participants at risk for coronary artery disease, atrial fibrillation, heart failure, stroke and dementia are invited for a visit to conduct an additional MRI examination of either heart or brain. Endpoint assessment of the overall sample will be completed through repeated follow-up examinations and surveys as well as related individual routine data from involved health and pension insurances. The study is targeting the complex relationship between biologic and psychosocial risk and resilience factors, chronic disease, health care use, survivorship and health as well as favorable and bad prognosis within a unique, large-scale long-term assessment with the perspective of further examinations after 6 years in a representative European metropolitan population.

Use of diffusion tension imaging in the evaluation of pediatric concussions

OBJECTIVE

To evaluate whether quantitative metrics of white matter fractional anisotropy (FA) and mean diffusivity (MD) were different in patients presenting to our clinic with persistent symptoms after a concussion.

DESIGN

Matched control retrospective study.

SETTING

Primary not-for-profit Institution.

PATIENTS

Consecutive patients seen at a primary care institution's Sports Concussion Clinic for sport-related concussion that underwent diffusion tensor imaging. Interventions (Independent variables): Type of sports, days from Injury, number of symptoms, weeks out when Magnetic Resonance Imaging (MRI) ordered, history of psychological issues, length of symptoms, age, sex, MRI imaging data.

MAIN OUTCOME MEASURE

Difference in white matter FA and MD.

RESULTS

Seventeen concussion patients, ages 9 and 17 (average = 12.5 years; median = 13 years, 11 males and 6 females), were matched with age and gender controls who had an MRI following a complaint of headache. Patients reported an average of 11.5 concussion symptoms, out of a total possible 22 and were seen at an average of 30 days post injury. No region met tract based spatial statistics criteria for significant differences between concussed and healthy control groups (all p > 0.05). Similarly, when comparing group averages from the atlas based regional summaries, no region met the 0.2 false discovery rate (FDR) threshold for significant differences (the smallest unadjusted p-values were 0.02 for MD and 0.14 for FA).

CONCLUSIONS

Our results did not show measurable diffusion tensor imaging (DTI) changes with standard clinical data acquisition and quantitative processing for the individual patient. At this time DTI should not be considered a technique that can diagnose concussion within an individual subject.

Assessment of Glioblastoma Response in the Era of Bevacizumab: Longstanding and Emergent Challenges in the Imaging Evaluation of Pseudoresponse

Glioblastoma is the deadliest primary malignant brain neoplasm, and despite the availability of many treatment options, its prognosis remains somber. Enhancement detected by magnetic resonance imaging (MRI) was considered the best imaging marker of tumor activity in glioblastoma for decades. However, its role as a surrogate marker of tumor viability has changed with the appearance of new treatment regimens and imaging modalities. The antiangiogenic therapy created an inflection point in the imaging assessment of glioblastoma response in clinical trials and clinical practice. Although BEV led to the improvement of enhancement, it did not necessarily mean tumor response. The decrease in the enhancement intensity represents a change in the permeability properties of the blood brain barrier, and presumably, the switch of the tumor growth pattern to an infiltrative non-enhancing phenotype. New imaging techniques for the assessment of cellularity, blood flow hemodynamics, and biochemistry have emerged to overcome this hurdle; nevertheless, designing tools to assess tumor response more accurately, and in so doing, improve the assessment of response to standard of care (SOC) therapies and to novel therapies, remains challenging.

Diagnostic accuracy of MRI with MRCP and B-Mode-sonography with elastography of the pancreas in patients with cystic fibrosis: a point-to-point comparison

Objective

For patients with cystic fibrosis, the imaging of the pancreas is of crucial importance for the early detection of pancreatic carcinoma. Comparative studies between Magnetic Resonance Imaging (MRI) and sonographic pancreas sonography are not yet available. The aim of the study was to compare MRI, sonography and point-shearwave elastography (pSWE). A total of 19 patients were included (10 male, 9 female; age 29.7 ± 14.3 years) in the study. Ultrasonography with pSWE and contrast enhanced MRI with MRCP were performed.

Results

Significant differences between measurements of pancreatic body were registered in MRI with 1.4 ± 0.6 cm vs 1.0 ± 0.4 cm in ultrasound (p = 0.049), however not for pancreatic head and tail. In 10/19 patients (52.6%) pancreatic parenchyma did not show in MRI because of complete lipomatous transformation, but could be detected in ultrasound. pSWE-values showed no significant differences between the full and partial fatty transformation in pancreatic head (p = 0.968), body (p = 0.657) and tail (p = 0.840). pSWE-values did not correlate with measured signal intensity in T1w flash (p = 0.930, r = 0.025) and T2w HASTE sequences (p = 0.152, r = − 0.375). In patients with CF ultrasound is superior to MRI for displaying full fibro-fatty parenchymal transformation, pancreatic duct. Ultrasound elastography did not provide additional clinical relevant information.

Electronic supplementary material

The online version of this article (10.1186/s13104-019-4193-4) contains supplementary material, which is available to authorized users.

Neuroblastoma-targeting triangular gadolinium oxide nanoplates for precise excision of cancer

Neuroblastoma accounts for 8-10% of malignancies in infants and children. It is urgent to develop an appropriate theranostic agent for effective diagnosis and therapy of neuroblastoma. Herein, we constructed RVG peptide and IRDye800-conjugated bovine serum albumin-coated triangular gadolinium oxide nanoplates (RVG&IRDye800-Gd₂O₃ TNs) as a targeting MRI agent for the diagnosis of neuroblastoma preoperation and a fluorescence imaging agent for the guidance of the precise excision of the neuroblastoma in surgery. RVG&IRDye800-Gd₂O₃ TNs have uniform edge length. The RVG&IRDye800-Gd₂O₃ TNs show remarkably enhanced affinity to both mouse- and human-derived neuroblastoma cells compared with IRDye800-Gd₂O₃ TNs (3.07-fold and 3.02-fold, respectively). Because of the increased accumulation in tumor cells, RVG&IRDye800-Gd₂O₃ TNs exhibit signals threefold to fivefold higher than the surrounding normal tissues, which is propitious to the diagnosis of neuroblastoma preoperation and provides real-time visual guidance of the precise excision of the neuroblastoma. Most importantly, with the guidance of the fluorescence imaging agent, the survival rate increased from 0% to 80% 42 days after surgery compared with that in conventional surgery. These findings indicated that the RVG peptide combined with IRDye800-Gd₂O₃ TNs has the potential to improve the diagnosis and treatment of patients with neuroblastoma. STATEMENT OF SIGNIFICANCE: In this study, we prepared RVG peptide and IRDye800-conjugated bovine serum albumin-coated triangular gadolinium oxide nanoplates (RVG&IRDye800-Gd₂O₃ TNs) as a targeting MRI agent for the diagnosis of neuroblastoma preoperation and a fluorescence imaging agent for the guidance of the precise excision of the neuroblastoma during surgery. Neuroblastoma was accurately located by MRI imaging, and the tumor margin could be real-time monitored through near-infrared fluorescence imaging. The RVG&IRDye800-Gd₂O₃ TNs exhibit signals threefold to fivefold higher than those in the surrounding normal tissues, which is propitious to the diagnosis of the neuroblastoma preoperation and provides real-time visual guidance of the precise excision of the neuroblastoma. With the guidance of the fluorescence imaging agent in surgery, the survival rate increased from 0% to 80% 42 days after surgery compared with that in conventional surgery.

Structural covariance in subcortical stroke patients measured by automated MRI-based volumetry

A network-level investigation of the volumetric changes of subcortical stroke patients is still lacking. Here, we explored the alterations of structural covariance caused by subcortical stroke with automated brain volumetry. T1-weighed brain MRI scans were obtained from 63 normal controls (NC), 46 stroke patients with infarct in left internal capsule (CI_L), 33 stroke patients with infarct in right internal capsule (CI_R). We performed automatic anatomical segmentation of the T1-weighted brain images with AccuBrain. Volumetric structural covariance analyses were first performed within the basal ganglia structures that were both identified by voxel-based morphometry with AAL atlas and AccuBrain. Subsequently, we additionally included the infratentorial regions that were particularly quantified by AccuBrain for the structural covariance analyses and investigated the alterations of anatomical connections within these subcortical regions in CI_L and CI_R compared with NC. The association between the regional brain volumetry and motor function was also evaluated in stroke groups. There were significant and extensive volumetric differences in stroke patients. These significant regions were generally symmetric for CI_L and CI_R group depending on the side of stroke, involving both regions close to lesions and remote regions. The structural covariance analyses revealed the synergy volume alteration in subcortical regions both in CI_L and CI_R group. In addition, the alterations of volumetric structural covariance were more extensive in CI_L group than CI_R group. Moreover, we found that the subcortical regions with atrophy contributed to the deficits of motor function in CI_R group but not CI_L group, indicating a lesion-side effect of brain volumetric changes after stroke. These findings indicated that the chronic subcortical stroke patients have extensive disordered anatomical connections involving the whole-brain level network, and the connections patterns depend on the lesion-side.

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Chronic subcortical stroke patients show extensive brain volumetric atrophy.

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Subcortical stroke patients show disordered structural covariance network pattern.

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Brain volumetric and connections patterns change depend on the lesion-side.

A Fast Method for Estimating Statistical Power of Multivariate GWAS in Real Case Scenarios: Examples from the Field of Imaging Genetics

In GWAS of imaging phenotypes (e.g., by the ENIGMA and CHARGE consortia), the growing number of phenotypes considered presents a statistical challenge that other fields are not experiencing (e.g. psychiatry and the Psychiatric Genetics Consortium). However, the multivariate nature of MRI measurements may also be an advantage as many of the MRI phenotypes are correlated and multivariate methods could be considered. Here, we compared the statistical power of a multivariate GWAS versus the current univariate approach, which consists of multiple univariate analyses. To do so, we used results from twin models to estimate pertinent vectors of SNP effect sizes on brain imaging phenotypes, as well as the residual correlation matrices, necessary to estimate analytically the statistical power. We showed that for subcortical structure volumes and hippocampal subfields, a multivariate GWAS yields similar statistical power to the current univariate approach. Our analytical approach is as accurate but ~ 1000 times faster than simulations and we have released the code to facilitate the investigation of other scenarios, may they be outside the field of imaging genetics.