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The purpose of this study was to determine the reliability and interobserver agreement of the liver imaging reporting and data system (LI-RADS) treatment response algorithm (LR-TR) v2018 using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and the added value of diffusion-weighted imaging (DWI).A total of 54 patients who underwent DCE-MRI and DWI after locoregional treatment of 81 hepatocellular carcinoma (HCC) lesions from September 2020 to July 2021 were included. There were 47 men and 7 women, with a mean age of 63.9 ± 9.2 (SD) years (age range: 23-77 years). Locoregional treatments included transarterial chemoembolization (TACE) (53/81; 65.4%), radiofrequency ablation (RFA) (25/81; 30.9%) and microwave ablation (MWA) (3/81; 3.7%). Two independent radiologists retrospectively evaluated DCE-MRI examinations obtained after locoregional treatment using LR-TR, and then three months later both radiologists reevaluated DCE-MRI examinations with DWI. Interobserver agreement was assessed using intraclass correlation coefficient (ICC) and Kappa test. Diagnostic performances were evaluated in term of sensitivity, specificity, and area under ROC curve (AUC) using a composite standard of reference that included results of histopathological examinations and follow-up findings.Using DCE-MRI alone, observer 1 had 83.9% sensitivity (26/31; 95% confidence interval [CI]: 66-95%), 88% specificity (44/50; 95% CI: 76-95%) and 86.4% accuracy (70/81; 95%CI: 77-93%), and observer 2 had 71% sensitivity (22/31; 95% CI: 52-86%), 92% specificity (46/50; 95% CI: 81-98%) and 83.9% accuracy (68/81; 95% CI: 74-91%). For the diagnosis of viable tumors using DCE-MRI with DWI, observer 1 and observer 2 had 87.1% (27/31; 95% CI: 70-96%) and 74.2% (23/31; 95% CI: 55-88%) sensitivity, respectively. The diagnostic performance of DCE-MRI with DWI yielded an AUC (0.875; 95% CI: 0.789-0.962) not different from that of DCE-MRI without DWI (0.859; 95% CI: 0.768-0.951) (P = 0.317). Interobserver agreement for arterial phase hyperenhancement, washout, enhancement similar to pretreatment and DWI findings in all treated HCCs was almost perfect (kappa = 0.815, 0.837, 0.826 and 0.81 respectively). Agreement between observers for LR-TR category was substantial (kappa = 0.795; 95% CI: 0.665-0.924). Interobserver agreement for size of viable HCC was excellent (ICC = 0.938; 95% CI: 0.904-0.960).LR-TR using DCE-MRI alone or DCE-MRI with DWI are both accurate for detecting viable HCC lesions after locoregional treatment, with no differences in diagnostic performance and excellent interobserver agreement.

Purpose The aim of this study is to highlight the predictive role of perinatal fetal main pulmonary artery (MPA) Doppler measurements in neonatal respiratory distress syndrome development. Respiratory distress syndrome (RDS) is one of the lead causes of neonatal respiratory distress as well as neonatal death. Thus, it seems logic to evaluate fetal lung maturity before labour. Methods The study is a prospective cohort study performed in tertiary hospital over a period of one-year duration. 70 pregnant ladies between 34 and 38 weeks of gestation were referred for fetal echo, when pregnancy was considered a high risk. A trained radiologist using dedicated ultrasound machine with updated obstetric and fetal echo software performed the fetal echo. Doppler mode and curvilinear probe of 5.7 MHz transducer. Pediatric neonatologist observed the neonatal outcome post-natally. Results A total of 70 pregnant patients with risk factors underwent fetal echo, 26/70 (37.1%) were diagnosed with RDS conforming to the neonatal criteria. The mean acceleration time/ejection time ratio (At/Et ratio) of the fetal pulmonary artery was significantly reduced in fetuses that subsequently developed RDS than those without RDS. Contrarily, the mean pulsatility index (PI), resistance index (RI), and peak systolic velocity (PSV) of the fetal pulmonary artery were significantly high in fetuses who later developed RDS than in those who did not. Conclusion Fetal MPA Doppler measurements have a major role in anticipating the development of neonatal RDS in preterm and early term neonates.

Background The purpose of this study was to investigate the diagnostic performance of diffusion weight imaging (DWI), apparent diffusion coefficient (ADC) map, normalized ADC liver, and normalized ADC spleen compared to the dynamic contrast-enhanced MRI (DCE-MRI) in the evaluation of residual hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA) using 3 T (T) magnetic resonance imaging (MRI). Results A prospective study was performed on 40 patients with radiofrequency-ablated HCC, and 15 (37.5%) patients had viable lesion post-RFA, while 25 (62.5%) had non-viable lesions. DCE-MRI had a sensitivity, specificity, and accuracy of 100%, 100%, and 100%, respectively, compared to DWI which had a sensitivity, specificity, and accuracy of 80%, 88%, and 85%, respectively, for identifying post-RFA viable HCC. The sensitivity, specificity, and accuracy of ADC at a cutoff value of 1.01 × 10−3 mm2/s were 80%, 100%, and 97.1%, respectively. The optimal cutoff value of normalized ADC liver was 0.81 with a sensitivity of 73.3%, specificity of 96%, and accuracy of 92.8%. The sensitivity, specificity, and accuracy of normalized ADC spleen at a cutoff value of 1.22 were 80%, 92%, and 91.1%, respectively. Conclusions DWI-MRI is a reliable technique for assessing HCC after radiofrequency ablation. DWI-MRI with ADC may be used as an alternate sequence for assessing radiofrequency-ablated lesions in individuals who have a contraindication to the contrast media, and the normalized ADC value may be of additional benefit.

Background: The diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) map and the dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) constitute the functional MRI technique with many oncological applications as it can define tissue microstructure and characterize the post-treatment changes from a recurrent tumor in treated head and neck squamous cell carcinoma (HNSCC). Objective: To evaluate the role of the DWI, ADC map and DCE-MRI for characterization of post-treatment changes and recurrent tumors in patients with treated HNSCC. Patients and Methods: Forty-five patients with treated HNSCC were included in this study with mean ages of 59 ± 7.5 years. The patients underwent pre and post-contrast head and neck MRI, DWI with ADC map and DCE-MRI, each study diagnosis was then compared to the patient outcome. Results: The sensitivity and specificity of the qualitative DWI (DW-MRI) (87.5% and 82.8% respectively) were higher than the conventional MRI (75% and 75.9% respectively). The ADC cut-off point for the diagnosis of HNSCC recurrence was 1.095 x10-3 mm2/s with sensitivity and specificity of 87.5%, 86.2% respectively. The DCE- MRI revealed a significant difference in the type of time intensity curve (TIC) between post-treatment changes and recurrent lesion (p-value < 0.0001). Conclusion: The DWI, ADC and the DCE-MRI can be used as a synchronized tool for the differentiation between post-treatment changes and recurrent tumor in treated HNSCC patients.

Objective COVID-19 infection is a systemic disease with various cardiovascular symptoms and complications. Cardiac MRI with late gadolinium enhancement is the modality of choice for the assessment of myocardial involvement. T1 and T2 mapping can increase diagnostic accuracy and improve further management. Our study aimed to evaluate the different aspects of myocardial damage in cases of COVID-19 infection using cardiac MRI. Methods This descriptive retrospective study included 86 cases, with a history of COVID-19 infection confirmed by positive RT-PCR, who met the inclusion criteria. Patients had progressive chest pain or dyspnoea with a suspected underlying cardiac cause, either by an abnormal electrocardiogram or elevated troponin levels. Cardiac MRI was performed with late contrast-enhanced (LGE) imaging, followed by T1 and T2 mapping. Results Twenty-four patients have elevated hsTnT with a median hsTnT value of 133 ng/L (IQR: 102 to 159 ng/L); normal value < 14 ng/L. Other sixty-two patients showed elevated hsTnI with a median hsTnI value of 1637 ng/L (IQR: 1340 to 2540 ng/L); normal value < 40 ng/L. CMR showed 52 patients with acute myocarditis, 23 with Takotsubo cardiomyopathy, and 11 with myocardial infarction. Invasive coronary angiography was performed only in selected patients. Conclusion Different COVID-19-related cardiac injuries may cause similar clinical symptoms. Cardiac MRI is the modality of choice to differentiate between the different types of myocardial injury such as Takotsubo cardiomyopathy and infection-related cardiomyopathy or even acute coronary syndrome secondary to vasculitis or oxygen-demand mismatch. Key Points • It is essential to detect early COVID-related cardiac injury using different cardiac biomarkers and cardiac imaging, as it has a significant impact on patient management and outcome. • Cardiac MRI is the modality of choice to differentiate between the different aspects of COVID-related myocardial injury.

Background To evaluate the inter- and intrareader agreement and reproducibility of the NI-RADS scoring system and lexicon with contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CEMRI). Methods This retrospective study included 97 CECT and CEMRI scans from 58 treated cases of head and neck squamous cell carcinoma (HNSCC) after the exclusion of head and neck cancers (HNCs) other than SCC and noncontrast and poor quality CT and MRI scans, with a total of 111 primary targets and 124 lymph node (LN) targets. Two experienced readers independently scored the likelihood of residual/recurrence for these targets based on the NI-RADS criteria and filled in report templates for NI-RADS lexicon diagnostic features. Inter- and intraobserver reproducibility was assessed with Cohen’s kappa, and the percent agreement was calculated. Results Almost perfect interreader agreement was found for the final NI-RADS category of the primary lesions and LNs, with K = 0.808 and 0.806, respectively. Better agreement was found for CT than for MRI (K = 0.843 and 0.77, respectively, P value 0.001). There was almost perfect agreement for excluding tissue enhancement (K = 0.826, 95% CI = 0.658–0.993, P value 0.001), with a percent agreement of 96.4%, and substantial agreement for discrete nodular and diffuse mucosal enhancement (K = 0.826, 95% CI = 0.658–0.993, P value 0.001), with a percent agreement of 96.4%. There was fair agreement for focal mucosal nonmass and deep ill-defined enhancement. The intrareader agreement was almost perfect for most of the rated features (K ranging from 0.802 to 1), with the exception of enlarging discrete nodule/mass and focal mucosal nonmass-like enhancement, which had substantial intraobserver agreement (K ranging from 0.768 to 0.786). Conclusion The individual features of NI-RADS show variable degrees of confidence; however, the overall NI-RADS category was not significantly affected.

Background: MRI is well known for being particularly useful for scanning and detecting abnormalities in soft tissue structures like the cartilage tissues, tendons, and ligaments. Moreover, MRI can also aid in determining those patients with knee injuries who will require surgical intervention. MR imaging is recognized as a standard procedure and has replaced diagnostic arthroscopy as the primary diagnostic modality for many knee pathologies. Furthermore, MR images can be used to assess anatomic variants that may contribute to chronic patellar instability. Aim of Study: To go over several of the most common causes of Anterior Knee Pain (AKP), with emphasis on their MRI findings with the goal of allowing diagnosis that is more accurate and grading of some of the most common pathologies, for interpreting, reaching an efficient treatment and drastic improvement of this common complaint. Patients and Methods: This study included 25 patients (8 females and 17 males). Their ages ranging between 10-60 years (average age 30 years). All presented by anterior knee pain and were referred to Radiology Department of Ain Shams University Hospital or private centers for MRI examination after orthopedic consultation. This descriptive study was done to detect the role of MRI in the evaluation of anterior knee pain and apply advanced MRI techniques such as sagittal T2 mapping to visualize the articular cartilage of the knee. Most patients were subjected to MR imaging of the affected knee joints on high field strength scanners using Philips scanners Achieva or Intera (1.5T). Results: The present study revealed that 26% patellar tendon disorders which included (patellar Tendinopathy 21% and Osgood Schlatter disease 5%). Quadriceps tendon disorders represented 10% and they are including (Quadriceps Tendin-opathy 5% and Quadriceps tendon tear 5%). 69% of the sample size showed Patellar disorders represent and they are including (chondromalacia patella 32%, patellar instability 21%, transient patellar dislocation 11% and painful bipartite patella 5%). Hoffa's disease was demonstrated in 21% of the sample size and they are including (Hoffa impingement syndrome and Hoffa ganglion cyst), finally we have torn anterior horn of the lateral meniscus and they represent 5%. Conclusion: MRI is generally safe, accurate, and specific modality, which has been proven to be the modality of choice in the diagnosis of different knee pathologies that cause anterior knee pain in different age groups. Also it has a high specification in detecting the grades and types of some of these diseases or factors predispose to them as patella Alta and trochlear dysplasia.

Background: The main aim of carotid imaging studies is the assessment of the carotid plaque morphology with the detection of vulnerable plaques which is associated with increased risk of cerebrovascular insult, hence proper deline-ation of plaque composition is a crucial step for further management of brain ischemic insult. Aim of Study: To define the inter method agreement between the carotid ultrasound and carotid MRI for charac-terization of vulnerable plaques with further assessment of carotid ultrasound sensitivity and specificity. Material and Methods: The study was conducted over 60 patients. The modified G-W classification was used to assess the sonographic features of the carotid plaques, and compared with the plaque composition using carotid MRI. Results: Our study included 60 patients, their ages ranged between 53 and 78 years with a mean age of 60.3±9.8 years. 56.7% of patients was male. The agreement between carotid ultrasound and carotid MRI was good with k=0.734, sensitivity of the carotid ultrasound to detect the vulnerable plaque was 88.1% with an overall accuracy of 88.3%. Conclusion: The carotid ultrasound examination is con-sidered the first-line modality for assessment of the carotid plaque composition, with good agreement with carotid MRI and acceptable sensitivity and accuracy for characterization of vulnerable plaques.

Background Hearing loss management using cochlear implants in patients with inner ear anomalies has long been discussed in the otology community. Magnetic resonances imaging (B,/IRI) and Computed tomography (CT) play important roles in the preoperative assessment of inner ear abnormalities such as cochlear nerve deficiency and variant anatomy as these abnormalities may not only affect the decision of the implantation procedure or the patient's prognosis regarding auditory improvement, but also the risk of complications. Objective To examine the prevalence of inner ear anomalies among cochlear implant recipients in patients with congenital sensorineural hearing loss among the pediatric age group in the Demerdash hospital, Ain Shams university using High resolution computed tomography (HRCT) and MRI imaging. Methods A retrospective descriptive study over the course of 9 months that included all patients that are candidates for cochlear implant referred to the Radiology department, Ain Shams University Hospitals for a preoperative imaging in the form of CT and VIRI scans. Results CT and MRI scans of 33 patients who had congenital hearing loss and were candidates for cochlear implantation with total 66 ears were reviewed. Inner ear anomalies were identified in 8 patients representing a prevalence (24.2%) with 14 ear diseased. Anomalies were seen bilaterally in 6 patients and unilaterally in 2 patients. Among the 14 diseased ear, 9 ears (64.3%) were seen with incomplete partition Il, 7 ears (50%) were seen with enlarged vestibular aqueduct, 4 ears (28.6%) were seen with cochlear hypoplasia, 3 ears (21.4%) were seen with semicircular canal aplasia, 2 ears (14.3%) were seen with incomplete partition type I, 2 ears (14.3%) were seen with cochlear nerve aplasia, 2 ears with cochlear aplasia (14.3%), I ear (7.1%) was seen with common cavity ear (7.1%) with complete labyrinthine aplasia. Conclusion Prevalence of inner ear anomalies among cochlear implant candidates was 24.2%. This result is consistent with results worldwide and the most common anomalies were Incomplete partition Il and large vestibular aqueduct. Abbreviations Computed tomography (CT), Magnetic resonance imaging (MRI), High resolution computed tomography (HRCT), Internal auditory canal (IAC), Cerebellopontine angle (CPA).

Background The transcatheter arterial chemoembolization (TACE) is one of the treatment lines for patients with hepatocellular carcinoma (HCC), this study was conducted to assess the role of functional imaging including the DWI, ADC and 18F-2-fluoro-2-deoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) for detection of residual HCC after TACE as compared to the structural liver imaging reporting and data system (LI-RADS). Results The optimal cut off value of standardized uptake value ratio (SUVmax/liver SUVmean ratio) for detection of residual viable HCC after TACE was 1.09 with 88.9%, 87.5% and 88.6% sensitivity, specificity, and accuracy respectively, a lower diagnostic value was noted in the qualitative visual FDG PET/CT assessment with sensitivity, specificity, and accuracy of 81.5%, 75% and 80% respectively. The sensitivity, specificity, and accuracy of DWI for identification of post-TACE viable HCC were 77.8%, 75%, and 77.1% respectively. The optimal cut off value of ADC for the diagnosis of variable HCC was 1.32 × 10−3 mm2/s with sensitivity, specificity, and accuracy of 81.5%, 75%, and 80% respectively. Conclusions DWI, ADC and FDG PET/CT are effective functional imaging modalities for the evaluation of viable residual HCC post-TACE with comparable findings for the dynamic cross-section imaging.

Background: MR cisternography using three dimensional (3D) heavily T2-weighted imaging techniques is considered the main imaging modality for identification and assessment of inner ear structures anatomy and pathology as well as for identification of the posterior fossa cranial nerves, and there are two techniques that are usually used which are fast spin-echo including Driven equilibrium (DRIVE) and fast gradient-echo techniques including Balanced fast field echo (bFFE).Aim of Study: To compare the image quality of 3D DRIVE and 3D bFFE sequences in the assessment of the inner ear structures and internal auditory canal cranial nerves.Material and Methods: 15 patients underwent MR imaging of the temporal bone using both 3D bFFE and 3D DRIVE sequences with a comparison between the two sequences as regards the clarity of cranial nerves and inner ear structures.Results: The 3D bFFE sequence was statistically signifi-cantly better than 3D DRIVE for demonstration of the cochlear, and vestibular nerves, and it was slightly better for visualizing the facial nerve as well as the cochlear inner structure. The 3D DRIVE showed a statically insignificant supremacy over 3D bFFE for visualization of the three semicircular canals and vestibule.Conclusion: The 3D bFFE shows slightly better imaging quality over 3D DRIVE with the advantage of less imaging time.

Background: Ovarian tumors are one of the most common women cancers. The high vascularity of malignant ovarian tumors can be assessed by the dynamic contrast enhanced MRI allowing preoperative characterization of ovarian lesions which help for planning the proper surgical management.Aim of Study: To evaluate the role of semiquantitative parameters of the dynamic contrast enhanced MRI in differ-entiation of ovarian lesions.Material and Methods: 25 patients with complex or solid ovarian lesions underwent dynamic contrast enhanced MRI (DCE MRI). The semiquantitative parameters including max-imum relative enhancement percentage (MRE%) and time to peak (Tmax) as well as the type of time intensity curve (TIC) were analyzed and compared to the histopathological results.Results: The MRE% was higher for malignant ovarian tumors than for benign (p

Background: Chronic shoulder pain affects the quality of life and limits daily activities. Suprascapular nerve block is an effective technique in management of chronic shoulder pain. Suprascapular injection technique had several drawbacks particularly repeated injections that may affect the patients' outcomes. RFA is considered a safe technique especially with ultrasound guidance, having a long duration of action with absence of any complications or organ damage.Aim of Study: This study aimed to examine the effective-ness of radiofrequency ablation (RFA) of the suprascapular nerve in comparison to the injection of lidocaine and hydro-cortisone mixture under ultrasound guidance.Patients and Methods: 20 patients with chronic shoulder pain were divided in to two equal groups one group was submitted to RFA of the suprascapular nerve using the Cool-Tip RF system and an internally cooled electrode (group A) and the other group had lidocaine and hydrocortisone mixture injection (group B) of the same nerve, both groups were followed-up over a period of 6 months with pre and post interventional assessment of the pain though visual analogue score for pain (VAS).Results: All patients had chronic shoulder pain not re-sponding to medical treatment and physiotherapy, after RFA, 6 patients were pain free, 4 cases had mild pain that responded to conservative treatment, regarding those of the injection group all cases had relief for 3 months, at 6 months, only 3 had no complain while 4 patients had recurrence and 3 had stationary course of pain relief.Conclusion: RFA proved to be a superior technique com-pared to the injection method in management of chronic shoulder pain.

Background: Detection of residual, recurrent, or second primary malignancies in head and neck cancers treated patients can be challenging. Soft tissue changes and anatomical disfigurement seen after surgery, radiotherapy, and chemotherapy can distort the anatomy of the head and neck and make post treatment imaging reporting very complex.Aim of work: To evaluate the performance of the Neck imaging, and reporting data system template recently created by the American College of Radiology (ACR) Committee in the prediction of local and regional disease recurrence or persistence of head and neck squamous cell carcinoma after treatment by using CE MRI/ CT, and PET-CT in inconclusive cases. Patients and Methods: 116 scans for 55patients with head and neck squamous cell cancerswere included after finishing their treatment, reporting done using the ACR NI-RADS reporting template and lexicon and NI-RADS category was assigned to each scan, the accuracy of this categorization was done by correlation with our gold standard: tissue pathological examination and/ or three months interval follow up scan. Results: Out of the 116 scans included in our study, we had 232 targets for primary tumour sites and lymph nodes, the overall tumour recurrence have occurred in 53 targets out of the total of 232, with a total tumour recurrence rate of 22.8%, the recurrence rates for each NI-RADS category for the primary tumour site were: 3.9% (2/51) for NI-RADS 1 category, 17.6% (3/17) for NI-RADS 2a category, 18.2% (4/22) for NI-RADS 2b category , and 76.9% (20/26) for NI-RADS 3 category. Regarding the lymph nodes, the recurrence rates for the different NI-RADS categories were: 3.8% (3/80) for NI-RADS 1 category, 7.1% (1/14) for NI-RADS 2 category, and 81.8% (18/22) for NI-RADS 3 category. The recurrence rates for combined NI-RADS categories for both the primary tumour site and lymph nodes were (Table 7): 3.8% (5/131) for NI-RADS 1 category, 19.6% (10/51) forNI-RADS 2 category, and 76.2% (38/48) for NI-RADS 3 category. Conclusion: The performance of the ACR NI-RADS reporting system and its linked management recommendations is excellent, with statistically significant discrimination in between the different NIRADS categories for either the primary tumour site, lymph nodes and for both combined. The use of NI-RADS can help to direct the management plans towards more proper options.

Background: The value of diffusion weighted imaging (DWI) in differentiation of pediatric posterior fossa tumors (PFTs)has been established previously, however most studies were limited only to the most common types of PFTs and their results were contradictory.. Aim of work: The aim of this study was to investigate the effectiveness of DWI in differentiation of PFTs taking care to include the less frequent types, and to clarify previously reported debatable findings. Patients and methods: We retrospectively analyzed 13 embryonal tumors (EMBTs), 4 ependymomas (EPNs),8 low grade gliomas (LGGs),2 mixed neuronal glial tumors (MNGTs), and 5 diffuse intrinsic pontine gliomas (DIPGs) . For all tumors, absolutemean ADC of the non necrotic enhancing portions of the tumor and ADC ratios of the solid enhancing region of the tumor to the ADC of normal appearing cerebellum were generated. The ADC metrics of the various groups (designated according to histological subtype and WHO grade) were compared using the kruskal – wallis and student-ttests. Receiver operating characteristic (ROC) curve analysis was used to generate cutoff absolute ADC values and ADC ratios for differentiation of different types of PFTs Results: Mean ADC values and ADC ratios were significantly lower in high than in low grade tumors (P 1.108× 10−3 (100% sensitivity and 92.3% specificity)but not with mean ADC values and from LGGs using a cutoff mean ADC value of ≤ 1.333 (100% sensitivity and specificity). No statistically significant difference (P >0.05) was seen between the mean ADC values of MNGTs (1.5+/-0.02) and LGGs (1.71+/-0.13) with wide overlap in their range of ADC values and ratios.Conclusion: Apart from a few exceptions, absolute ADC values and ratios go a long way in enabling pre-operative differentiation of different types of PFTs.

Background The idiopathic intracranial hypertension is a disease that is represented by high intracranial pressure of unknown reason. The visual disturbance presents the main medical problem of this syndrome. This study was conducted to assess the diagnostic value of the optic nerve sheath diameter (ONSD) measured using MRI 3D DRIVE in the diagnosis of idiopathic intracranial hypertension. Results The mean value of the ONSD measured using 3D DRIVE sequence in the patient group (5.81 ± 0.33) was significantly higher than the mean value of the normal control group (4.95 ± 0.45) (p 5.31 mm, with 94.12% sensitivity and 93.3% negative predictive value. Conclusion The high resolution of 3D DRIVE provides an accurate measurement of ONSD which correlated with elevated cerebrospinal fluid pressure and hence the diagnosis of idiopathic intracranial hypertension.

This paper presents a novel platform for accurate mathematical modeling of the propulsion system of electric cars. It provides, for the first time, a hardware-in-the-loop (HIL) real-time experimental verification case study of a General Motor Chevrolet Volt for power, control systems, and the mechanical systems. The contribution of this paper can be categorized into three approaches: First, each component of the powertrain is accurately modeled taking transient dynamics of all components of the electric vehicle into consideration. Further, a PSIM simulation platform is consequently developed to demonstrate the validity of this mathematical modeling. Finally, the Typhoon HIL is used to provide the experimental verification of the proposed model in real time, which precisely validates the viability of the model. HIL technology is used to prototype and test the proposed control system while simulating the power circuit on the HIL module platform. The permanent magnet synchronous motor and the power electronics hardware components are simulated in real time at which the parameters can be changed during the simulation. However, the control algorithm is generated as a C code and downloaded to the TI controller that exists on a digital signal processing board. The results from the simulation based on PSIM environment and hardware validations using HIL are in agreement, which validates the developed model. The performance has been investigated under different load operating conditions in real time to verify its robustness. The case study can be extended for any electric car as it provides a generic platform for modeling any propulsion system.

This study introduces a novel methodology based on an extensive mathematical analysis, performed from basic electromagnetic principles, with an optimized cost for a magnetic levitation Hyperloop system. This new approach uses both permanent magnets and electromagnets to levitate, propel, and control a pod. The electrodynamic suspension system is emulated as a small pod attached with permanent magnets from the bottom, which resembles a short-rotor linear synchronous motor. A comprehensive finite-element analysis using ANSOFT Maxwell software on the effects of the magnetic field distribution of the coils due to the ac current flowing through them is investigated. The effects of the magnetic force exerted on the permanent magnet secondary are examined as well. The whole magnetic levitation system prototype was implemented in the laboratory as a proof of concept in order to validate and verify the simulation results. The simulation results are in full agreement with the mathematical analysis, which assures the validity of the design procedure and the magnetic analysis.

Objectives: To evaluate the diagnostic performance of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) for the characterization of complex ovarian tumors, by using histologic findings as the reference standard. Patients and methods: 25 patients (age range from 24 to 60) with complex ovarian masses underwent DCE-MRI before surgical excision. The study included 8 benign, 3 borderline & 14 malignant masses. The following kinetic parameters were analyzed: enhancement amplitude (EA) in the form of MRE%, time to peak in the form of T max & maximal slope (MS) & correlated with histopathological results. Results: DCE-MRI achieved higher overall accuracy (85.7%) & specificity (86.5%) than conventional MRI. MRE% was higher for malignant than for benign (p0.001) & borderline masses (p0.002). T max was of shorter duration in malignant than in benign (p, < 0.001) and borderline (p, 0.018) masses. Type III curve was specific for invasive malignant tumors. Conclusion: DCE-MRI can be a useful tool in characterization of complex ovarian masses & in differentiating between borderline & invasive malignant neoplasms.

This paper introduces a unique quantified study about using low-losses fast-switching wide bandgap (WBG) devices, i.e., gallium nitride (GaN) and silicon carbide (SiC), over traditional Silicon (Si) devices in the switching of dc/dc converters, focusing on electric vehicles’ (EVs) machine drive and battery charger. A detailed model of the power train of a Nissan Leaf was developed in PSIM software, with WBG semiconductors’ capability. The model was simulated one time using GaN semiconductors and another time using SiC devices. Simulation results are quantified and a comparison between different semiconductors in terms of total losses and efficiency is presented. The developed PSIM model can also be extended to other EVs like Chevy Volt. A proof of concept prototype for a Nissan Leaf dc/dc converter was built in the laboratory and results were collected. Componentwise experimental results are presented and their correlation with simulation findings is demonstrated. In addition, experimental results of the overall power train test bench are found to be matched with the simulation results on a system level as well.

Background: the initial evaluation of obstructive jaundice involves distinguishing between intra and extra hepatic biliary obstruction. The goal of any radiologic procedure is to confirm the presence of biliary obstructive by detecting biliary dilatation, its exact location, extent and probable cause. Aim of the Study: to evaluate the role of Magnetic Resonance Cholangio-Pancreatography in differentiating benign from malignant causes of biliary obstruction using surgical, ERCP or histopathological findings as a gold standard.Patients and Methods: a prospective study done on 20 patients with clinical and laboratory finding suggestive of biliary obstruction. All patients underwent non enhanced MRCP on 1.5 Tesla machine (Philips). The final diagnosis of MRCP was correlated with results of ERCP in addition to biopsy and histological diagnosis to those patients had neoplasms. Results: Out of 20 cases, there were 11 benign and 9 malignant cases. Mean age of patients with malignant obstruction was more than benign with slight female preponderance. The diagnostic accuracy of MRCP in differentiating benign from malignant biliary obstructive diseases in correlation with surgical, ERCP and histopathological outcome was85.7%, 96.3%, and 93.3% respectively. It was found that irregular, asymmetric and long segment narrowing was more common in malignant stricture. Conclusion: MRCP is a rapid and non-invasive, procedure in assessing cases with suspicions biliary obstructions. It offered a diagnostic accuracy nearly equivocal to ERCP. MRCP can also replace the diagnostic part of ERCP procedure, so that time is spent only on its th erapeutic part, and hence decreasing complications of a lengthy ERCP. Recommendations: benign or malignant nature of biliary obstruction can be assured by MRCP by observation of stricture margin, dilatation, and length and accordingly proceed to next step in management. MRCP is an efficient diagnostic procedure for detection of presence, level, cause of obstruction and routinely advocated before any intervention is planned.

This paper introduces a novel engineering feasibility study for developing a future hybrid metro system, for the first time in Canada, that is of extremely low cost and independent of the utility grid. This system will eliminate the need of the rail cars to rely on the track substations and consequently the utility grid. This paper is based on the load profiles provided by Bombardier Transportation for its advanced rapid transit train running in Vancouver, BC, Canada. Simulation was performed for propulsion with and without auxiliary power with the assumption of an average power of 40 kW. To size the system for the worst case scenario, the regeneration power will not be taken into account in case the propulsion cuts off during regenerative braking. The subsystem modules described in the model are listed for reference purposes. The hydrogen consumption and storage are also calculated for each case with the tank options listed for each energy storage option. Furthermore, an analysis platform is being provided for a sound design of a hybrid metro car for the first time in North America. This systematic modular approach can be easily applied to any transit system worldwide. A successful design for a fuel cell hybrid train is given, which is fully independent on the electricity from the grid. The elimination of the wayside substations system, which is 90% of the cost of the transit system, presents huge initial and running cost savings and makes the rail car ridership very inexpensive.

In this paper, a performance comparison is conducted through experimental setup between induction machine based water pump (IM-based pump) and permanent magnet synchronous machine based water pump (PMSM-based pump). Both pumps, under test, are chosen to deliver that same water flow quantity Q at similar pressure head H allowing the comparison to be focused only on the performance of the electrical machines; with the same mechanical loading. A laboratory test rig is constructed and the electrical data are collected by data logging system, while each pump run for the same period of time. The results have been discussed to highlight the merits of the performance of the PMSM-based pumps over IM-based ones.

This paper presents a novel methodology on the design and analysis, performed from basic principles, with an optimized cost for a magnetic levitation Hyperloop system. It uses permanent magnets and electromagnets to levitate, propel, and control a pod. A comprehensive investigation with the help of a detailed finite element analysis on the effects of the magnetic field distribution, due to the alternating current being applied to the propulsion and levitation system, was provided. Simulations from ANSOFT Maxwell are given. A short-rotor linear synchronous motor (LSM) was designed as a small pod with permanent magnets at the bottom to emulate the electrodynamic suspension system. Furthermore, the effects of the magnetic field force, exerted on the permanent magnet rotor, were also examined. The whole magnetic levitation system prototype was implemented experimentally, as a proof of concept prototype, in order to verify the simulation results. The results are given to assure the validity of the magnetic analysis, design procedure, simulation results, and experimental results.