Foci Of High Signal Intensity Research Articles

Evaluation of left atrial function and tissue after pulmonary vein isolation - initial results of The EVALUATE-PVI STUDY

Abstract Background Pulmonary vein (PV) isolation (PVI) by catheter ablation is a well-established treatment for atrial fibrillation (AF). Currently, the direct and long-term impact of ablation injury on left atrial (LA) function and tissue is poorly understood. Purpose The aim of this study is to evaluate the acute and long-term impact of radiofrequency (RF) PVI ablation on LA function and corresponding tissue changes as assessed with cardiac magnetic resonance imaging (CMR). Methods Seventeen patients (76.5% male, 60.8±9.7 years) with AF who underwent primo RF PVI as part of the EVALUATE-PVI STUDY underwent three sequential CMR scans prior to PVI, and <72 hours and 3 months after PVI ablation. T2-weighted turbo spin echo imaging was applied to assess post-ablation edema. High-resolution three-dimensional (3D) late gadolinium-enhancement (LGE) images were acquired to study acute LA wall injury and chronic fibrosis formation. LA volume and function were derived from two-chamber and four-chamber SSFP cine images. Maximum and minimal LA volume was indexed to body surface area to compute LAVimax and LAVimin. Longitudinal LA strain was calculated using feature tracking, and subdivided into reservoir, conduit, and contractile strain. Results Acutely post-PVI, T2w images showed increased signal intensity and thickening throughout the entire LA wall. LGE images showed diffuse increased signal intensity, without distinct focal high signal intensity areas (Fig. 1). Functional assessment at this stage showed significantly reduced LA emptying fraction (EF), LA reservoir, and contractile strain compared to pre-PVI (54.8±11.1% vs. 48.5±7.9%, p=0.01; 18.6±5.6% vs. 14.6±2.0%, p<0.01; 8.5±3.5% vs. 5.2±1.8%, p<0.001, respectively), while LA conduit strain, LAVimin, and LAVimax did not differ significantly (Fig. 2). The LGE images acquired at 3 months, displayed clear, focal, high signal intensity areas surrounding the PVs. At this stage post-PVI, a significant increase in LA strain was observed (LA reservoir strain 14.6±2.0% vs. 16.9±3.5%, p<0.01; and contractile strain 5.2±1.8% vs. 6.7±2.9%, p<0.01; respectively). LAVimax was significantly reduced at 3 months compared to acutely post-PVI (Fig. 2). LAVimin and LA conduit strain did not differ between the pre- and post-PVI stages. Conclusion PVI ablation resulted in temporary reduced LA function acutely post-PVI, likely due to edema and thickening of the LA wall. At three months, LGE images revealed clearly visible increased signal intensity in the ablated segments. At this stage, LA function improved, though full recovery did not occur as evidenced by the persistent slightly reduced contractile strain, possibly due to the ablation-induced loss of LA myocardium and formation of fibrosis. The decrease in LAVimax indicates reverse remodeling as a result of the ablation.

The MR mammography of phyllodes tumors of different histological grades

Purpose: to evaluate retrospectively the MR data of the breast phyllodes tumors and to perform comparative analysis of the MR signs and the histological grade of the phyllodes tumors.Materials and methods. The analyses enrolled 27 pathologically confirmed phyllodes tumors (mean age of patient 37.8 y.o.). Following features were evaluated: tumor shape and structure, margins, size, type of contrast enhancement, foci of high signal intensity on the T1-WI, foci of hypo- or isointense signal on the T2-WI comparing with intact breast tissue, presence of cystic inclusions and the type of their margins.Results. The study included 18 benign, 4 borderline and 5 malignant phyllodes tumors. The following features showed significant correlation with the tumor grade: irregular margins of the cystic foci (p = 0.003), foci of hypoor isointense signal on the T2-WI compared with intact breast tissue (p = 0.005). Foci of high signal intensity on the T1-WI were often revealed in the malignant (3/5) and borderline tumors (2/4), but this dependence was not significant (p = 0.021). According to pathomorphological correlation the foci of the high signal intensity on the T1-WI corresponded to hemorrhages, while cystic foci with irregular margins were revealed to be foci of necrosis. The foci of hypo- or isointense signal on the T2-WI compared with intact breast tissue corresponded to the hypercellular stroma.Conclusion. Specific features of phyllodes tumors are useful in differentiation of their histological types; furthermore the MR mammography provides accurate data for planning the point of biopsy.

Predicting Adenomyosis Diagnosis Based on MRI

<h3>Study Objective</h3> Development of a prediction tool for histopathological adenomyosis diagnosis after hysterectomy based on MRI and clinical parameters. <h3>Design</h3> Single-centre retrospective cohort study. <h3>Setting</h3> Gynaecological department of regional referral hospital from 2007-2022. <h3>Patients or Participants</h3> 296 women undergoing a hysterectomy for benign pathology with preoperative pelvic MRI. <h3>Interventions</h3> MRI's were retrospectively re-assessed for all possible adenomyosis markers (junctional zone (JZ) parameters, high signal intensity foci (HSI foci), uterine size) in a blinded fashion by two researchers. Sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy, and odds ratio (dOR) were calculated. Threshold values of continuous variables were investigated using Receiver Operator Characteristics (ROC) curves and Area Under the Curve (AUC). A multivariate regression model for histopathological adenomyosis diagnosis was developed based on selection of MRI and clinical variables from univariate analysis with p>0.10 and factors determined to be of clinical importance. <h3>Measurements and Main Results</h3> 131 women (44.3%) had histopathological adenomyosis. In univariate analysis, patients had comparable age at hysterectomy, BMI and clinical symptoms, p>0.05. Patients with adenomyosis had more often undergone a curettage (221% vs. 8.9%, p=0.002), and had a higher mean JZ (9.35mm vs. 8.00, p=0.001), maximal JZ (15.05mm vs. 12.45mm, p=0.002), mean JZ to myometrium ratio (0.53 vs. 0.48 p=0.009) and JZ differential (8.45mm vs, 6.75mm, p=0.009). Presence of HSI foci on MRI was quasi-pathognomic for adenomyosis diagnosis (25.5% vs. 2.4%, p<0.001). A predictive model based on the parameters of: Age at MRI, History of Curettage, Dysmenorrhoea, Hypermenorrhoea, Mean JZ, JZ differential, JZ/Myometrium ratio, Presence of HSI Foci was created, with a good AUC of 0.761. <h3>Conclusion</h3> This is the first study to create a clinical diagnostic tool based on a combination of MRI and clinical parameters for adenomyosis diagnosis. As preoperative imaging-based diagnosis of adenomyosis remains challenging, this model, after sufficient external validation, could function to become a useful clinical-decision making tool in women with suspected adenomyosis.

Utility of 3D Double Inversion Recovery Sequence in Paediatric Epilepsy and its Comparison to 3D Fluid Attenuation Inversion Recovery Sequence and T1 Inversion Recovery Sequence : A Cross-sectional Study

Introduction: Epilepsy is a disease with predisposition to generate epileptic seizures, associated with neurobiological, cognitive, psychological, and social consequences. Nearly 30% of children undergoing medical treatment for epilepsy become refractive to the treatment. For those children, the ability to find the epileptogenic area is higher with Magnetic Resonance Imaging (MRI) of the brain. The traditional 2D spin-echo sequences used in epilepsy protocol for adults cannot be used alone in paediatric structural neuroimaging. Additional sequences are needed to identify epileptogenic areas due to differences in myelination. Here, present study compared the role of three volumetric sequences 3D-Fluid Attenuated Inversion Recovery (FLAIR) , 3D-T1 weighted Inversion Recovery (T1-IR) and 3D-Double Inversion Recovery (DIR) for paediatric epilepsy as part of structural neuroimaging. Aim: To assess the utility of 3D-DIR in paediatric epilepsy disorders and localisation of epileptogenic foci in brain, congenital malformations of brain and compare its findings with 3D-FLAIR and 3D-T1-IR. Materials and Methods: The present study was a cross-sectional study of children diagnosed with paediatric epilepsy, who were evaluated with MRI brain at Stanley Medical College, Chennai, Tamil Nadu, India, between April 2020 to April 2021 with three sequences, 3D-DIR, 3D-T1-IR and 3D-FLAIR. Lesions of atleast 3 mm in diameter were identified as foci of high signal intensity and counted in each of the three sequences separately and classified according to their location. Then, average signal intensities of the lesions were calculated manually on each of sequences using Region of Interest (ROI) analysis which had a mean size of 3 mm2 . Then the Signal-to-Noise Ratio (SNR), Contrast to-Noise Ratio (CNR), Contrast Ratio (CR), and Asymmetry Signal Ratio (ASR) were calculated. Results: Evaluation was done on 51 paediatric epilepsy patients and showed the total number of lesions detected (208 lesions) and measured contrast parameters (CR, CNR and ASR) which were found to be significantly higher in 3D-DIR, showed higher detection of the intracortical and white matter lesions than 3DFLAIR and 3D-T1-IR. SNR was higher in 3D-FLAIR. Conclusion: Present study concluded that the greatest value of the DIR sequence has a higher ability in detecting epileptogenic foci and congenital malformations of the lesions in comparison with FLAIR and T1-IR.

Differential Diagnosis of Intraplaque Hemorrhage and Dissection on High-Resolution MR Imaging in Patients with Focal High Signal of the Vertebrobasilar Artery on TOF Imaging.

Purpose: Intraplaque hemorrhage (IPH) and dissection in the vertebrobasilar artery (VBA) on time of flight (TOF) source imaging are seen as focal eccentric high-signal intensity. The purpose of this study is to identify IPH and dissection in the VBA using high-resolution magnetic resonance imaging (HR-MRI). Methods: A total of 78 patients (VBA IPH: 55; dissection: 23) with focal high-signal intensity in the VBA on simultaneous non-contrast angiography and intraplaque hemorrhage (SNAP) of HR-MRI were included in this study. The focal high-signal intensity in the VBA on SNAP was defined as >200% than that of the adjacent muscle. We analyzed the signal intensity ratio (area of focal high signal intensity area/lumen) on TOF imaging and black blood (BB) T2-weighted imaging. Results: The VBA IPH group was older than the dissection group and had more hypertension. Signal intensity of a false lumen in patients with dissection on TOF imaging was significantly higher than that of VBA IPH (p < 0.001). The signal intensity ratio between lumen and lesion on TOF imaging was significantly higher in the dissection group (p < 0.001). The signal intensity of a false lumen in patients with dissection on BB T2-weighted imaging was significantly lower than that of VBA IPH (p < 0.001). The signal intensity ratio between lumen and lesion on BB T2–weighted imaging was significantly higher in the VBA IPH group (p < 0.001). Conclusions: TOF imaging and BB T2-weighted imaging on HR-MRI in patients with focal eccentric high-signal intensity on TOF imaging can distinguish between VBA IPH and dissection.

Neuroimaging in Pediatric Optic Neuritis: A Narrative Review

ContextPediatric optic neuritis can occur in isolation or association with neuroinflammatory disorders. We reviewed the abnormal orbital and cranial magnetic resonance imaging in literature diagnosed as pediatric optic neuritis, which was primarily presented with visual problems.Evidence AcquisitionA PubMed literature search was accomplished using the following key terms: “Neuroimaging, “Pediatric, “Optic Neuritis, “Multiple Sclerosis, and “Magnetic Resonance Imaging.ResultsPoorly demarcated changes in white and or gray matter, well-demarcated white matter changes, confluent lesions in white matter, and small nonspecific lesions or nothing in some areas of the brain are the most common patterns of children with optic neuritis. The thin, fat suppression imaging technique can reveal optic nerve lesions. Contrast-enhanced sequences, especially by short tau inversion recovery, allow differentiation of particular high-signal intensity foci in the optic nerve and newly formed active lesions from inactive lesions.ConclusionsBrain imaging should be performed in all patients, if possible, during the two weeks after the initial diagnosis. The cranial neuroimaging can predict multiple sclerosis development in pediatric patients with demyelinating brain lesion

RARE COMPLICATION OF A RARE DISEASE

SESSION TITLE: Pulmonary Pathology II SESSION TYPE: Med Student/Res Case Report PRESENTED ON: 10/21/2019 3:15 PM - 4:15 PM INTRODUCTION: Primary pulmonary lymphoma (PPL) comprises of only 1% of pulmonary malignancies and has been described with systemic autoimmune diseases. It may be associated with a fatal disease known as intravascular lymphoma which is extremely rare and can lead to a diagnostic dilemma. CASE PRESENTATION: 58 year old female with history of Sjögren’s syndrome presented to the pulmonology clinic with complaints of shortness of breath cough and low grade fever for 2 weeks. She was vitally stable with bronchial breath sounds at the right lower lung zone. Chest X-ray showed right middle lobe collapse. The CT scan chest after 2 weeks of conservative treatment showed soft tissue density in the bronchus intermedius (BI). Bronchoscopy revealed pinkish lesion in BI. The histopathology showed high grade B cell Non-Hodgkin's lymphoma. The patient was started on chemotherapy with R-CHOP (rituximab, cyclophosphamide, doxorubicin and prednisolone). After third cycle of chemotherapy she was admitted with fever and bodyaches. She became increasingly somnolent and dropped her GCS requiring intubation. The MRI brain showed diffusely scattered foci of signal dropout on SWI throughout the brain, predominantly in the corpus callosum and diffuse multifocal areas of diffusion restriction in periventricular and subcortical white matter. Lumbar puncture and EEG were negative. Brain biopsy was not attempted considering her clinical instability. She was treated with pulse steroids leading to improvement in GCS. A follow up MRI after pulse therapy showed interval improvement of the brain lesions. DISCUSSION: We believe that our case describes the presentation of a malignancy which progressed to develop a rare complication known as Intravascular lymphoma (IVL); it is a subtype of extranodal large B-cell lymphoma which spreads in angiotropic pattern to virtually any organ of the body, brain and skin being the most common sites. The gold standard of diagnosis is histological evidence of intravascular invasion but studies are being reported to identify noninvasive modalities of diagnosis of IVL (1). Recent literature reports various neuroimaging findings of IVL like multiple foci of high signal intensity in the deep white matter, infarct like changes and intracranial mass (2). Treatment of IVL is based on the RCHOP regimen, however prognosis is poor (3). The responsiveness to steroid therapy supports the diagnosis of IVL. CONCLUSIONS: A high index of suspicion is required to diagnose IVL in patients with Non-Hodgkins who present with neurological symptoms. An emerging evidence supports the use of neuroimaging in diagnosis of IVL in patients without tissue diagnosis. Reference #1: Shimada K, Kinoshita T, Naoe T, Nakamura S. Presentation and management of intravascular large B-cell lymphoma. The lancet oncology. 2009 Sep 1;10(9):895-902 Reference #2: Yamamoto A, Kikuchi Y, Homma K, O'uchi T, Furui S. Characteristics of intravascular large B-cell lymphoma on cerebral MR imaging. American Journal of Neuroradiology. 2012 Feb 1;33(2):292-6 Reference #3: Baehring JM, Longtine J, Hochberg FH. A new approach to the diagnosis and treatment of intravascular lymphoma. Journal of neuro-oncology. 2003 Feb 1;61(3):237-48 DISCLOSURES: no disclosure on file for Arsalan Ahmad; No relevant relationships by Hasaan Omar, source=Web Response No relevant relationships by Aqusa Zahid, source=Web Response No relevant relationships by Ali Zubairi, source=Web Response

Endplate and intervertebral disc injuries in acute and single level osteoporotic vertebral fractures: is there any association with the process of bone healing?

BackgroundThe endplate-intervertebral disc (IVD) complex is closely interrelated with the vertebral body (VB) in the structural integrity of the anterior spinal column, including biomechanical and biological functions. Endplate and IVD injuries are usually found in association with vertebral fractures (VFs); however, little is known about their relevance to the healing of osteoporotic VFs (OVFs). The first purpose of this study was to evaluate the incidence and occurrence pattern of endplate and IVD injuries associated with single- and acute-OVFs, and the second was to evaluate the influence of endplate and IVD injuries on the occurrence of delayed union.MethodsEndplate and IVD injuries associated with single- and acute-OVFs were retrospectively evaluated using magnetic resonance imaging (MRI). Vertebrae of 168 patients were included in the study. The occurrence rate and type of endplate and IVD injuries were radiologically evaluated, and the association between endplate and IVD injuries was statistically analyzed. Vertebrae of 85 patients, who received conservative treatment for acute OVFs, were included in the study and classified into two groups, union and delayed union, at 6 months after injury. To identify factors predicting delayed union, uni- and multivariate statistical analyses were performed. Vertebral MRI signal alternation patterns and endplate and IVD injuries were included as candidate factors in the logistic model.ResultsIn association with OVFs, endplate injuries were observed in 103 of the 168 vertebrae (61%), and IVDs lesions were observed in 101 of 168 OVFs (60%); the occurrence of both injuries was significantly associated. Although no significant association with endplate and IVD injuries was identified, multivariate analysis demonstrated that intravertebral signal alternation (focal high signal intensity) and posterior wall injury were independent risk factors that predicted delayed union.ConclusionsThe results of this study showed that endplate and IVD injuries were found in approximately 60% of single and acute OVFs. These results suggest that fracture healing of OVFs would be mainly attributed to vertebral factors, including mechanical stress and metabolic status, among the three components of the anterior spinal column.

Ivy Sign Predicts Ischemic Stroke Recurrence in Adult Moyamoya Patients without Revascularization Surgery

Background: Although there is a standard guideline for performing revascularization surgery in patients with Moyamoya diseases (MMD), more objective and easily obtainable predictors are still needed. Objectives: In this study, we aimed to evaluate the relationship between an ipsilateral ivy sign and ischemic stroke recurrence in adult MMD patients without revascularization surgery. Methods: We included consecutive MMD patients without revascularization surgery between 2006 and 2014. The ivy sign was defined as a linear or focal high-signal intensity on fluid-attenuated inversion recovery images, and the burdens of ivy sign were rated in each hemisphere. The ischemic stroke recurrence was defined as a new clinical event that accompanied a new brain lesion on magnetic resonance imaging. Results: Overall, 84 patients with 154 hemispheres were analyzed. We found recurrent ischemic stroke in 9 (6%) hemispheres within 3 years. In multivariate analysis, an ipsilateral ivy sign remained an independent predictor of 3-year ischemic recurrence (adjusted hazard ratio [aHR] 10.15, 95% CI 2.10–49.14, p = 0.004). An initial presentation as infarction was also significant (aHR 7.15, 95% CI 1.36–36.78, p = 0.019). The burdens of ivy sign showed a dose-response tendency with the 3-year ischemic recurrence rate (p < 0.001). When comparing the ischemic recurrence rate among 4 groups with and without ivy sign and perfusion defect, the “Ivy sign (+) Perfusion defect (+) group” showed a significantly higher risk in both observed (p = 0.005) and estimated (p = 0.003) 3-year ischemic recurrence than did the other group. Additionally, the “Ivy sign (+) Perfusion defect (–) group” showed a higher recurrence rate than did the “Ivy sign (–) Perfusion defect (+) group”. Conclusions: The ivy sign is associated with ischemic recurrence in adult MMD patients in a dose-response manner. It would be helpful for selecting high-risk patients who need revascularization surgery.

MRI An Imaging Tool To Evaluate Cerebral Changes In Victims Of Heat Stroke Presenting With Cerebral Symptoms

Heat stroke usually presents as medical emergency that causes altered cerebral status and deterioration of multiple organ functions. Heat stroke leads to many different physiological changes within the body, some of which result in neurologic dysfunction. The imaging characteristics of neurological changes of heat stroke are not well documented in literature although the pathophysiologic mechanism of neuronal damage is fairly well understood. We conducted a study to evaluate the imaging appearances of human brain after heat stroke on MRI presented with cerebral symptoms. Material and methods: The retrospective study conducted in radiology department of Ziauddin university hospital from May 2015 till July 2016. All the patients with heat stroke presented with neurological deficit were underwent MRI brain, evaluated by two senior radiologists. Results: 56 patients were included in study, 12 female and 44 male, all patients had clinical symptoms of fever and most of them had additional symptoms of altered level of consciousness. Out of 54 patients, 8 patients had normal MRI brain. 6 patients presented with bilaterally symmetrical hyperintense signals on T2WI in thalami and basal ganglia. 2 patients demonstrated focal high signal intensity in pons representing pontine myelinosis, rest of the patients presented with cerebral or cerebellar infarcts. Conclusion:Many cerebral lesions can result as cerebral damage of heat stroke which includes cerebral infarct, white matter changes, haemorrhages and inflammatory reactions, in these clinical scenarios MRI would be imaging modality of choice to evaluate the disease pattern.

Whole body MRI in spondyloarthritis (SpA): Preliminary results suggest that DWI outperforms STIR for lesion detection.

To compare the diagnostic accuracy of DWI and STIR sequences in Whole body (WB) MRI of SpA patients. Twenty consecutive patients with confirmed active SpA and 20 controls were investigated with identical WB MRI protocols, including DWI and STIR images. Two observers recorded 'lesions' (high signal intensity foci on STIR and high b-value DWI) in 17 anatomical areas, making a 17-point 'area score' and a 40-point 'lesion score'. ROC performance, inter-observer agreement, correlation with clinical parameters and spine and sacro-iliac joints (SIJ) MRI scores were assessed. SpA patients had significantly higher lesion scores on DWI than on STIR (p<0.025). The lesion score area under the curve was significantly higher with DWI (99.9) than with STIR (95.8, p=0.02). DWI lesion score ≥5 had both sensitivity and specificity ≥85 %. With STIR the best threshold ≥3 yielded sensitivity ≥85 % and specificity ≥60 %. DWI area score ≥3 yielded sensitivity ≥85 % and specificity ≥80 %. With STIR the best threshold ≥4 yielded sensitivity ≥70 % and specificity ≥80 %. Inter-observer agreement was strong for both sequences. In patients, the lesion score was positively correlated with ASDAS-CRP, log(CRP), and local MRI scores. DWI is a promising alternative to STIR in WB MRI to detect active SpA lesions. • DWI is a robust alternative to STIR in WBMRI in SpA. • DWI might be superior in discriminating relevant inflammatory and degenerative changes. • Positive correlations exist between WB MRI, clinical, biological, local MRI data. • Distribution and frequency of abnormal MRI findings in SpA are highlighted.

Detection of the Tram Track Lesion in the Ankle Joint: Comparing 3.0-Tesla Magnetic Resonance Imaging and Arthroscopy

To show the effectiveness of magnetic resonance imaging (MRI) for the detection of tram track lesions in the ankle compared with ankle arthroscopy. We retrospectively assessed all patients who underwent arthroscopic ankle surgery between January 2013 and July 2015. Patients with anterior impingement spurs were included, but those with an osteochondral lesion or arthritis were excluded. Anterior ankle bony spurs on preoperative weight-bearing radiographs were scored using an impingement classification system. The 3.0-tesla MRIs were reviewed for tram track lesions (defined as focal high signal intensity along the talar dome cartilage surface on coronal views) and compared with arthroscopic findings. The cartilage defect grade at arthroscopy was stratified according to the International Cartilage Repair Society (ICRS) grading system. Overall, 175 ankles in 170 patients were evaluated. Tram track lesions were identified on MRI in 14 ankles (8.0%) and at arthroscopy in 16 ankles (9.1%). The overall sensitivity of MRI for the detection of tram track lesions was 87.5% and the specificity was 100%. On plain weight-bearing radiographs, of the 16 patients with confirmed tram track lesions on arthroscopy, 4 patients had grade 1, 2 had grade 2, and 10 had grade 3 impingement spurs. Under the ICRS grading system, 4 patients had grade II, 4 had grade III, and 8 had grade IV cartilage defects at arthroscopy. On MRI, 2 patients had grade II (50% of arthroscopy), 4 had grade III (100% of arthroscopy), and 8 had grade IV defects (100% of arthroscopy). The impingement spur grade showed no significant correlation with the arthroscopic ICRS grade of the tram track lesion (P= .609). Tram track lesions can be confidently detected on MRI with high sensitivity and specificity. The impingement spur grade did not correlate with the severity of cartilage injury of the talar dome. Level III, diagnostic evaluation study.

Posterior Reversible Encephalopathy Syndrome After Ustekinumab Induction

Biological agents are frequently used in the management of inflammatory bowel disease, and understanding the potential adverse effects of these therapies is markedly important. We report a case of posterior reversible encephalopathy syndrome (PRES), a serious but often reversible neurological disorder, in a young patient with Crohn's disease following induction with ustekinumab. The patient is an 18 year-old Dominican female with Crohn's disease diagnosed 6 years ago with ileocolonic involvement and stricturing and fistulizing phenotype. Since diagnosis, her disease was managed in a step-up fashion with oral mesalamine, 6-mercaptopurine, methotrexate (MTX) and infliximab with periods of medication non-adherence. In the year leading up to presentation, she had multiple complicated hospitalizations due to active Crohn's disease. During this time, infliximab was increased to 10 mg/kg every 4 weeks and MTX was continued weekly. The patient presented to our hospital with abdominal pain after receiving an outpatient infliximab infusion. CT scan showed worsening small bowel disease with new enterocolic and enteroenteric fistulas. Serologic drug monitoring revealed detectable infliximab trough level and low titer anti-drug antibodies. Given the lack of clinical response, infliximab was stopped and ustekinumab (390 mg IV) was subsequently administered 1 week after the last MTX dose. Twelve days after ustekinumab induction, the patient had observed tonic-clonic seizures. Subsequent evaluation was notable for hyponatremia, and MRI brain showed bilateral foci of high signal intensity on T2/FLAIR imaging within the frontal, parietal and occipital lobes consistent with PRES. The patient was started on anti-epileptic medications, and had no further seizures or neurological deficits. Due to concern for PRES as cause of the seizure, ustekinumab was not continued. PRES is a rare and typically reversible neurological disorder that can present with headache, seizure, altered consciousness, and visual change, and may result in death. Neuroimaging reveals symmetric posterior cerebral white matter edema. Only one case of PRES was observed in the ustekinumab clinical trials for psoriasis and psoriatic arthritis, and no cases of PRES were seen during trials of ustekinumab for the management of moderate to severe Crohn's disease. To our knowledge this is the first case reported of PRES occurring after ustekinumab treatment in a patient with Crohn's disease.

Detection of Tram Track Lesion in the Ankle Joint; A Comparative Study of Magnetic Resonance Imaging with Ankle Arthroscopy

Category: Ankle, Arthroscopy Introduction/Purpose: Tram track lesion in the ankle joint has been occasionally found during the ankle arthroscopy and there has been few studies relating the pathophysiology, diagnostic method and treatment of the lesion. This study aimed to show the effectiveness of magnetic resonance imaging (MRI) for detection of tram track lesion in the ankle joint comparing with ankle arthroscopy. Methods: We retrospectively assessed 175 ankles in 170 patients with anterior bony impingement syndrome in the ankle who underwent arthroscopic surgery between January 2013 and July 2015. Anterior ankle bony spurs were scored in preoperative weight-bearing radiographs using the impingement classification. MRIs were reviewed for the detection of tram track lesions according to our definition (focal high signal intensity along the talar dome cartilage surface on coronal view), which were then compared with arthroscopic findings. The grade of cartilage defect was stratified according to international cartilage repair society (ICRS) grading system by arthroscopic finding. Results: Fourteen (8.0%) ankles were identified with tram track lesion on MRI and 16 (9.1%) ankles were identified with tram track lesion at ankle arthroscopy. Overall sensitivity of MRI for detection of tram track lesion was 87.5% and specificity was 100%. On plane weight-bearing radiographs, 4 patients had grade 1, 2 patients had grade 2 and 10 patients had grade 3 impingement spurs. Under the ICRS grading system, 4 cases were grade 2, 4 cases were grade 3, and 8 cases were grade 4 at arthroscopy. Comparing with MRI, 2 cases of grade 2, 4 cases of grade 3 and 8 cases of grade 4 were detected (Table). Impingement spur grade showed no significant correlation with arthroscopic ICRS grade of tram track lesion (p = 0.609). Conclusion: Tram track lesions in the ankle joint can be confidently detected on MRI with high sensitivity and specificity. Early detection and following treatment of the lesion can maximize the clinical outcome that eliminates the possibility for further damage to the cartilage and consequent osteoarthritic change.

Growing Cyst-Like White Matter Lesions in Children With Neurofibromatosis Type 1

BackgroundNeurofibromatosis type 1 (NF1) is an autosomal dominant disease with prominent neurocutaneous manifestations. The most common intracranial imaging finding of NF1 on brain magnetic resonance imaging (MRI) is the high-signal intensity foci without a mass effect or growth in size. Patient DescriptionWe describe two children with NF1 in whom brain MRI showed growing cystic lesions and adjacent white matter signal abnormalities, which were confirmed as non-neoplastic cystic degeneration and reactive gliosis. ConclusionGrowing cyst-like white matter lesions can be seen on serial brain MRI in children with NF1. Reactive gliosis with cystic degeneration could be a pathogenic basis of these cystic lesions.

High intensity focused ultrasound treatment of adenomyosis: The relationship between the features of magnetic resonance imaging on T2 weighted images and the therapeutic efficacy

ObjectivesTo investigate the relationship between the features of magnetic resonance imaging (MRI) on T2 weighted images (T2WI) and the therapeutic efficacy of high intensity focused ultrasound (HIFU) on adenomyosis. Materials and methodsFrom January 2011 to November 2015, four hundred and twenty-eight patients with symptomatic adenomyosis were treated with HIFU. Based on the signal intensity and the number of hyperintense foci in the adenomyotic lesions on T2WI, the patients were classified into groups. The day after HIFU ablation patients underwent contrast-enhanced MRI and a comparison was made of non-perfused volume (NPV) ratio, energy efficiency factor (EEF), treatment time, sonication time, and adverse effects. ResultsNo significant difference in terms of HIFU treatment settings and results was observed between the group of patients with hypointense adenomyotic lesions and the group with isointense adenomyotic lesions (P>0.05). However, the sonication time and EEF were significantly higher in the group with multiple hyperintense foci compared to the group with few hyperintense foci. The NPV ratio achieved in the lesions with multiple hyperintenese foci was significantly lower than that in the lesions with few hyperintense foci (P<0.05). No significant difference was observed in the rate of adverse effects between the two groups. ConclusionsBased on our results, the response of the adenomyotic lesions to HIFU treatment is not related to the signal intensity of adenomyotic lesions on T2WI. However, the number of the high signal intensity foci in the adenomyotic lesions on T2WI can be considered as a predictive factor to help select patients for HIFU treatment.

Clinical and low field magnetic resonance imaging features of osseous cyst‐like lesions of the proximal sesamoid bones in seven horses

SummaryOsseous cyst‐like lesions of the proximal sesamoid bones (PSBs) were diagnosed in 7 horses. The diagnosis was achieved radiographically prior to magnetic resonance imaging (MRI) in only one horse, and in the other 6 horses the diagnosis was made using low field MRI (retrospective evaluation of the radiographs after the MRI revealed ill‐defined radiolucencies of the PSBs in 4 of these horses). The horses ranged in age from 3 to 12 years, and the affected limbs included 3 forelimbs and 4 hindlimbs. The onset of lameness was reported to be sudden in 6 horses and insidious in one, and the duration of lameness at the time of MRI ranged from 0.3 to 11 months. The degree of lameness in the 6 horses with sudden‐onset lameness was moderate to severe. Pain on flexion of the affected metacarpo(tarso)phalangeal (fetlock) joint or exacerbation of the degree of lameness following fetlock flexion was recorded in 4 of the 7 horses. The MRI findings in all cases included a focal high signal intensity lesion (all magnetic resonance sequences) at various locations in one PSB. Both septic and nonseptic aetiologies were identified. Four of the 7 horses were subjected to euthanasia due to persistent lameness, one remained chronically lame and only 2 were able to return to their previous level of exercise.

Mycoplasma pneumoniae infection with neurologic complications

Extrapulmonary complications of Mycoplasma pneumoniae (M. pneumoniae) infection include encephalitis, optic neuritis, acute psychosis, stroke, cranial nerve palsies, aseptic meningitis and also it may be implicated in immune mediated neurological diseases such as acute demyelinating encephalomyelitis, Guillain-Barre syndrome and transverse myelitis. We present five cases with acute neurological diseases after M. pneumoniae infection. The clinical presentations were characterized by encephalitis in 2 patients, Gullain-Barre syndrome in 2 patients, transverse myelitis in 1 patient. M. pneumoniae infection was detected in serum by serological method. Only two patients had respiratory symptoms preceding M. pneumoniae infection. Brain MRI revealed hyperintensities on corpus striatum and mesencephalon in one patient with encephalitis, the other had front parietal coalescent periventricular white matter lesions on T2 images. The patient with transverse myelitis had cervical, dorsal and lumbar scattered hyperintense lesions on T2 images. Two patients were treated with high dose steroid, the other two patients received treatment with intravenous immune globuline. M. pneumoniae may reveal different neurologic complications with different radiologic findings.

Differentiation of intrahepatic mass-forming cholangiocarcinoma from hepatocellular carcinoma on gadoxetic acid-enhanced liver MR imaging.

To determine the different imaging features of intrahepatic mass-forming cholangiocarcinoma (IMCC) from hepatocellular carcinoma (HCC) on gadoxetic acid-enhanced magnetic resonance imaging (MRI). This retrospective study was institutional review board approved and the requirement for informed consent was waived. Patients who underwent gadoxetic acid-enhanced MRI with histologically confirmed IMCCs (n = 46) or HCCs (n = 58) were included. Imaging features of IMCCs and HCCs on gadoxetic acid-enhanced MRI including T2- and T1-weighted, diffusion weighted images, dynamic study and hepatobiliary phase (HBP) images were analyzed. Univariate and multivariate logistic regression analyses were performed to identify relevant differentiating features between IMCCs and HCCs. Multivariate analysis revealed heterogeneous T2 signal intensity and a hypointense rim on the HBP as suggestive findings of IMCCs and the wash-in and "portal wash-out" enhancement pattern as well as focal T1 high signal intensity foci as indicative of HCCs (all, p < 0.05). When we combined any three of the above four imaging features, we were able to diagnose IMCCs with 94% (43/46) sensitivity and 86% (50/58) specificity. Combined interpretation of enhancement characteristics including HBP images, morphologic features, and strict application of the "portal wash-out" pattern helped more accurate discrimination of IMCCs from HCCs. • Analysis of enhancement characteristics helped accurate discrimination of IMCCs from HCCs. • Wash-out should be determined on the PVP of gadoxetic acid-enhanced MRI. • A hypointense rim on the HBP was a significant finding of IMCCs.

(492) Pulsed RF of cervical nerve root for the treatment of cervical radicular pain: a prospective and randomized study

(492) Pulsed RF of cervical nerve root for the treatment of cervical radicular pain: a prospective and randomized study