High-precision frequency-controlled optical phase shifter with acousto-optic devices.

A fundamental parameter to determine how electromagnetic waves interfere is their relative phase, and achieving a fine control over it enables a wide range of interferometric applications. Existing phase control methods rely on modifying the optical path length either by changing the path followed by the light or by altering the thickness or index of refraction of an optical element in the setup. In this Letter, we present a novel, to the best of our knowledge, method, based on acousto-optic modulators (AOMs), which allows adjusting the phase by shifting the frequency of the light in a segment of its path. Since the amount of phase shift depends on the length of the segment, an optical fiber is used to realize a 2π shift. Two experimental implementations are described which deal with different sources of phase fluctuations. The first addresses fluctuations resulting from the optical fiber, while the second tackles unwanted variations originating from the AOMs.

Homogeneous Organic Reductant Based on 4,4'-tBu2-2,2'-Bipyridine for Cross-Electrophile Coupling.

The synthesis of a new homogeneous reductant based on 4,4'-tBu2-2,2'-bipyridine, tBu-OED4, is reported. tBu-OED4 was prepared on a multigram scale in two steps from inexpensive and commercially available starting materials, with no chromatography required for purification. tBu-OED4 has a reduction potential of -1.33 V (vs Ferrocenium/Ferrocene) and is soluble in a range of common organic solvents. We demonstrate that tBu-OED4 can facilitate Ni/Co dual-catalyzed C(sp2)-C(sp3) cross-electrophile coupling reactions and is highly functional group tolerant. tBu-OED4 is expected to be a valuable addition to the set of homogeneous reductants available for organic transformations.

The hidden dangers of the coronary anomalies: an ARCAPA case report.

An anomalous origin of the right coronary artery from the pulmonary artery case report. The diagnosis was made by angiotomography. Reimplantation of the right coronary artery into the ascending aorta and reconstruction of the pulmonary artery were conducted.

Impact of calibrating a low-cost capacitance-based soil moisture sensor on AquaCrop model performance.

Sensor data and agro-hydrological modeling have been combined to improve irrigation management. Crop water models simulating crop growth and production in response to the soil-water environment need to be parsimonious in terms of structure, inputs and parameters to be applied in data scarce regions. Irrigation management using soil moisture sensors requires them to be site-calibrated, low-cost, and maintainable. Therefore, there is a need for parsimonious crop modeling combined with low-cost soil moisture sensing without losing predictive capability. This study calibrated the low-cost capacitance-based Spectrum Inc. SM100 soil moisture sensor using multiple least squares and machine learning models, with both laboratory and field data. The best calibration technique, field-based piece-wise linear regression (calibration r2 = 0.76, RMSE = 3.13 %, validation r2 = 0.67, RMSE = 4.57 %), was used to study the effect of sensor calibration on the performance of the FAO AquaCrop Open Source (AquaCrop-OS) model by calibrating its soil hydraulic parameters. This approach was tested during the wheat cropping season in 2018, in Kanpur (India), in the Indo-Gangetic plains, resulting in some best practices regarding sensor calibration being recommended. The soil moisture sensor was calibrated best in field conditions against a secondary standard sensor (UGT GmbH. SMT100) taken as a reference (r2 = 0.67, RMSE = 4.57 %), followed by laboratory calibration against gravimetric soil moisture using the dry-down (r2 = 0.66, RMSE = 5.26 %) and wet-up curves respectively (r2 = 0.62, RMSE = 6.29 %). Moreover, model overfitting with machine learning algorithms led to poor field validation performance. The soil moisture simulation of AquaCrop-OS improved significantly by incorporating raw reference sensor and calibrated low-cost sensor data. There were non-significant impacts on biomass simulation, but water productivity improved significantly. Notably, using raw low-cost sensor data to calibrate AquaCrop led to poorer performances than using the literature. Hence using literature values could save sensor costs without compromising model performance if sensor calibration was not possible. The results suggest the essentiality of calibrating low-cost soil moisture sensors for crop modeling calibration to improve crop water productivity.

Supraventricular tachyarrhythmia and sinus node dysfunction as a first manifestation of short QT syndrome in a pediatric patient. Case Report.

Short QT syndrome (SQTS) represents a diagnosis challenge where the symptoms may vary from palpitations in an otherwise asymptomatic patient to sudden death. Is a recently discovered rare channelopathy, identified by Gussak in 2000, characterized by short QT intervals on the electrocardiogram and a tendency to develop atrial and ventricular arrhythmias in the absence of structural heart disease, hyperkalemia, hypercalcemia, hyperthermia, acidosis and endocrine disorders. We present the case of a 16-year-old patient with short QT-type channelopathy, who presented with sinus arrest and junctional rhythm, who later developed atrial tachycardia and atrial flutter.

Body composition and phase angle by bioimpedance in patients with MAFLD. / Análisis de la composición corporal y ángulo de fase por bioimpedancia en pacientes con MAFLD.

OBJECTIVE: To describe the characteristics of the body components and phase angle (PhA) of patients with MAFLD according to those different to fibrosis and hepatic steatosis. MATERIAL AND METHODS: Observational and descriptive study in a cohort of 585 volunteers from our center with MAFLD criteria. The risk of liver fibrosis was determined by APRI, NAFLD score and FIB-4; at an indeterminate and high risk of fibrosis, a transient elastography (Fibroscan®) were realized. Bioimpedance body composition analysis (SECA®) was performed. Patients with ET and SECA® registry were included. Bioimpedance body composition analysis (SECA®) was performed. Patients with ET and SECA® registry were included. RESULTS: 125 participants (21.4%) were evaluated, age 53.9±13.9 years, 62.1% women, BMI 33.2±5.8kg/m2. The SECA® analysis showed mean fat mass of 42%±7.32 and muscle mass 21.18kg±6.6. The PhA was 5.1±0.69, in women 4.92±0.62 and men 5.41±0.70. PhA in patients without fibrosis was 5.091 vs with fibrosis 5.121 (P=.813). In advanced fibrosis, it reported a low value compared to the rest of the groups (P=.031). The PhA in S3 was higher compared to S1 and S2 (5.3 vs 4.82, 4.81) (P=.027). CONCLUSIONS: In MAFLD, the PhA was lower than the healthy Mexican population. In patients without fibrosis and severe steatosis, PhA rises proportionally to the increase in fat mass and BMI and in advanced liver fibrosis, PhA decreases.

Use of Infliximab in the Treatment of Macrophage Activation Syndrome Complicating Kawasaki Disease.

Kawasaki disease (KD) is an acute systemic vasculitis of unknown etiology. KD can be complicated with macrophage activation syndrome. The optimal treatment for this KD complication has not been established, and a variety of treatments have been used. Infliximab, a chimeric monoclonal antibody that binds tumor necrosis factor, has proved to be efficacious in IV gammaglobulin resistant KD. We present 2 cases of KD complicated with macrophage activation syndrome, including 1 patient with DiGeorge syndrome successfully treated with a combined treatment of IV gammaglobulin, corticosteroids, cyclosporine, and infliximab.

Impact on prostate cancer clinical presentation after non-screening policies at a tertiary-care medical center- a retrospective study.

BACKGROUND: In May 2012 the US Preventive Task Force issued a 'D' recommendation against routine PSA-based early detection of prostate cancer. This recommendation was implemented progressively in our health system. The aim of this study is to define its impact on prostate cancer staging at a tertiary care institution. METHODS: A retrospective analysis was performed from 2012 until 2015 at a single center. We analyzed the total number of biopsies performed per year and the positive biopsy rate. For those patients with positive biopsies we recorded diagnostic PSA, clinical stage, ISUP grade group, nodal involvement and metastatic status at diagnosis. RESULTS: A total of 1686 biopsies were analyzed. The positive biopsy rate increased from 25% in 2012 to 40% in 2015 (p < 0.05). No change in median PSA was noticed (p = 0.627). The biopsies detected higher ISUP grades (p = 0.000). In addition, newly diagnosed prostate cancer presented a higher clinical stage (p = 0.005), higher metastatic rates (p = 0.03) and a tendency to higher lymph node involvement although not statistically significant (p = 0.09). CONCLUSION: After the 2012 recommendation, patients presented a higher probability of a prostate cancer diagnosis, with a more adverse ISUP group, clinical stage and metastatic disease. These results should be taken into consideration to implement a risk adapted strategy for prostate cancer screening.

Integration of Remote Sensing and Mexican Water Quality Monitoring System Using an Extreme Learning Machine.

Remote Sensing, as a driver for water management decisions, needs further integration with monitoring water quality programs, especially in developing countries. Moreover, usage of remote sensing approaches has not been broadly applied in monitoring routines. Therefore, it is necessary to assess the efficacy of available sensors to complement the often limited field measurements from such programs and build models that support monitoring tasks. Here, we integrate field measurements (2013-2019) from the Mexican national water quality monitoring system (RNMCA) with data from Landsat-8 OLI, Sentinel-3 OLCI, and Sentinel-2 MSI to train an extreme learning machine (ELM), a support vector regression (SVR) and a linear regression (LR) for estimating Chlorophyll-a (Chl-a), Turbidity, Total Suspended Matter (TSM) and Secchi Disk Depth (SDD). Additionally, OLCI Level-2 Products for Chl-a and TSM are compared against the RNMCA data. We observed that OLCI Level-2 Products are poorly correlated with the RNMCA data and it is not feasible to rely only on them to support monitoring operations. However, OLCI atmospherically corrected data is useful to develop accurate models using an ELM, particularly for Turbidity (R2 = 0.7). We conclude that remote sensing is useful to support monitoring systems tasks, and its progressive integration will improve the quality of water quality monitoring programs.

Differential Pressure Spirometry for Mechanical Ventilation Using Dichotomic Search.

In invasive mechanical ventilation (IMV), it is critical that the flow value is estimated correctly, as it is used as a trigger variable for ventilatory assistance. Furthermore, the numerical integration of the flow allows the calculation of the total volume per breath (tidal volume), which clinicians use to identify trauma or lung capacity in the patient. The current COVID-19 pandemic has demonstrated the need to develop safe and efficient techniques for measuring this spirometry variable because many mechanical ventilators delivered to hospitals were unable to measure it directly. A good device to estimate flow is a D-lite sensor, which works by the Venturi effect, is cheap, reusable, and proximal to the patient. However, the regressions applied to the flow estimation model are limited for use in real conditions. This article presents a flow estimation method that uses a D-Lite device, a fraction of inspired oxygen (FiO2) cell, and two pressure sensors as critical items. Our novel method adapts the dichotomous search algorithm instead of conventional regression algorithms to estimate flow using a D-lite sensor; this change in the standard procedure allowed us a fast calibration process, a good low-flow estimation, and low computational time for flow estimation. The method was validated experimentally to compute the tidal volume according to the measurement requirement error range of +/-10%. The consideration of FiO2 percentage in the gas mixture and the good low-flow estimation make this novel method useful for real ventilation conditions. The flow calculations have been performed at different ambient conditions and compared with gas analyzers show an average relative error of up to 4.86%. Finally, we present an analysis of the error flow estimation considering the variation in each variable. Technical recommendations for applying this novel method to achieve IMV safely are presented, based on the capabilities of the embedded system used by developers.

Relationships between mitral annular calcification and cardiovascular events: A meta-analysis.

BACKGROUND: Mitral annular calcification (MAC) is prevalent in the aging population, with recent renewed interest regarding its associations with cardiovascular risk factors, outcomes, and influence on valvular heart disease and interventions. This meta-analysis aimed to report the relationships between MAC and cardiovascular mortality and morbidity events. METHODS: Relevant studies were searched from PubMed, Cochrane, and Embase databases until November 30, 2019. Associations between MAC as a binary variable with death and cardiovascular events were pooled using random-effects models. The main outcomes of interest were all-cause and cardiovascular mortality, myocardial infarction, stroke, heart failure, atrial fibrillation, and procedural outcomes. RESULTS: Among 799 article abstracts and 122 full-text articles screened, 26 (16 prospective and 10 retrospective) studies totaling 35 070 subjects were analyzed. MAC was associated with higher all-cause death, hazard ratio (95% confidence interval) 1.76 (1.43-2.22), and cardiovascular mortality 1.85 (1.45-23.5). It also positively correlated with myocardial infarction 1.48 (1.22-1.79), stroke 1.51 (1.22-2.05), incidental heart failure 1.55 (1.30-1.84), atrial fibrillation 1.75 (1.43-2.15), and their composite, major adverse cardiovascular events (MACE). Finally, conversion to mitral valve replacement at time of cardiac surgery was more in patients with MAC than without MAC, with odds ratio (95% confidence interval) 2.82 (1.28-6.18). CONCLUSION: Mitral annular calcification was overall associated with higher rates of death, and both individual and composite cardiovascular events. The presence of increasingly encountered MAC has significant clinical implications for cardiovascular risk assessment and valvular interventions.

Duodenal mucosal resurfacing: proof-of-concept, procedural development, and initial implementation in the clinical setting.

BACKGROUND AND AIMS: We aimed to develop duodenal mucosal resurfacing (DMR), a minimally invasive upper endoscopic hydrothermal ablation procedure, to treat insulin-resistant metabolic diseases. METHODS: We completed a sham-controlled, rodent proof-of-concept study and longitudinal safety study in pigs to demonstrate feasibility to test DMR in humans. Subsequently, the DMR procedure was implemented in an open-label first-in-human (FIH) study of safety and efficacy in patients with type 2 diabetes (T2D). RESULTS: In rats, duodenal abrasion reduced hyperglycemia by 59 mg/dL on average, compared with no change from baseline in the sham treatment arm (P < .05). In pigs, the balloon catheter successfully and safely delivered hydrothermal ablation to the duodenal mucosa and superficial submucosa. Complete mucosal healing was demonstrated by week 6. In the FIH study, hydrothermal ablation was successfully administered with no evidence of perforation, pancreatitis, or hemorrhage. Duodenal biopsy specimens obtained 3 months postprocedure demonstrated full mucosal regrowth. No inflammation was observed, and there was minimal-to-mild collagen banding deposition observed in a proportion of ablation site biopsy specimens with no evidence of fibrotic scarring. Glycemic and hepatic measures improved through 6 months of follow-up. CONCLUSIONS: DMR shows potential as an endoscopic intervention that improves glycemic and hepatic parameters in patients with T2D. Further mechanistic and clinical studies are underway to further explore DMR as a treatment for metabolic disease.

Degenerative Mitral Stenosis: Unmet Need for Percutaneous Interventions.

Degenerative mitral stenosis (DMS) is an important cause of mitral stenosis, developing secondary to severe mitral annular calcification. With the increase in life expectancy and improved access to health care, more patients with DMS are likely to be encountered in developed nations. These patients are generally elderly with multiple comorbidities and often are high-risk candidates for surgery. The mainstay of therapy in DMS patients is medical management with heart rate control and diuretic therapy. Surgical intervention might be delayed until symptoms are severely limiting and cannot be managed by medical therapy. Mitral valve surgery is also challenging in these patients because of the presence of extensive calcification. Hence, there is a need to develop an alternative percutaneous treatment approach for patients with DMS who are otherwise inoperable or at high risk for surgery. In this review, we summarize the available data on the epidemiology of DMS and diagnostic considerations and current treatment strategies for these patients.

Electrical stimulation therapy of the lower esophageal sphincter is successful in treating GERD: long-term 3-year results.

BACKGROUND: Electrical stimulation of the lower esophageal sphincter (LES) has been shown to improve outcomes in patients with gastroesophageal reflux disease (GERD) at 2 years. The aim of the study was to evaluate the safety and efficacy of LES stimulation in the same cohort at 3 years. METHODS: GERD patients with partial response to PPI, with % 24-h esophageal pH < 4.0 for >5 %, with hiatal hernia <3 cm and with esophagitis ≤LA grade C were treated with LES stimulation in an open-label 2-year trial. All patients were on fixed stimulation parameter of 20 Hz, 220 µs, 5 mA delivered in twelve, 30-min sessions. After completing the 2-year open-label study, they were offered enrollment into a multicenter registry trial and were evaluated using GERD-HRQL, symptom diaries and pH testing at their 3-year follow-up. RESULTS: Fifteen patients completed their 3-year evaluation [mean (SD) age = 56.1 (9.7) years; men = 8] on LES stimulation. At 3 years, there was a significant improvement in their median (IQR) GERD-HRQL on electrical stimulation compared to both their on PPI [9 (6-10) vs. 1 (0-2), p = 0.001] and off PPI [22 (21-24) vs. 1 (0-2), p < 0.001]. Median 24-h distal esophageal acid exposure was significantly reduced from [10.3 (7.5-11.6) % at baseline vs. 3 (1.9-4.5) %, p < 0.001] at 3 years. Seventy-three % (11/15) patients had normalized their distal esophageal acid exposure at 3 years. Remaining four patients had improved their distal esophageal acid exposure by 39-48 % from baseline. All but four patients reported cessation of regular PPI use (>50 % of days with PPI use); three had normal esophageal pH at 3 years. There were no unanticipated device- or stimulation-related adverse events or untoward sensation reported during the 2- to 3-year follow-up. CONCLUSION: LES-EST is safe and effective for treating patients with GERD over long-term, 3-year duration. There was a significant and sustained improvement in esophageal acid exposure and reduction in GERD symptoms and PPI use. Further, no new GI side effects or adverse events were reported.

Size does not always matter: Ts65Dn Down syndrome mice show cerebellum-dependent motor learning deficits that cannot be rescued by postnatal SAG treatment.

Humans with Down syndrome (DS) and Ts65Dn mice both show a reduced volume of the cerebellum due to a significant reduction in the density of granule neurons. Recently, cerebellar hypoplasia in Ts65Dn mice was rescued by a single treatment with SAG, an agonist of the Sonic hedgehog pathway, administered on the day of birth. In addition to normalizing cerebellar morphology, this treatment restored the ability to learn a spatial navigation task, which is associated with hippocampal function. It is not clear to what extent this improved performance results from restoration of the cerebellar architecture or a yet undefined role of Sonic hedgehog (Shh) in perinatal hippocampal development. The absence of a clearly demonstrated deficit in cerebellar function in trisomic mice exacerbates the problem of discerning how SAG acts to improve learning and memory. Here we show that phase reversal adaptation and consolidation of the vestibulo-ocular reflex is significantly impaired in Ts65Dn mice, providing for the first time a precise characterization of cerebellar functional deficits in this murine model of DS. However, these deficits do not benefit from the normalization of cerebellar morphology following treatment with SAG. Together with the previous observation that the synaptic properties of Purkinje cells are also unchanged by SAG treatment, this lack of improvement in a region-specific behavioral assay supports the possibility that a direct effect of Shh pathway stimulation on the hippocampus might explain the benefits of this potential approach to the improvement of cognition in DS.

RpoS integrates CRP, Fis, and PhoP signaling pathways to control Salmonella Typhi hlyE expression.

BACKGROUND: SPI-18 is a pathogenicity island found in some Salmonella enterica serovars, including S. Typhi. SPI-18 harbors two ORFs organized into an operon, hlyE and taiA genes, both implicated in virulence. Regarding the hlyE regulation in S. Typhi, it has been reported that RpoS participates as transcriptional up-regulator under low pH and high osmolarity. In addition, CRP down-regulates hlyE expression during exponential growth. Previously, it has been suggested that there is another factor related to catabolite repression, different from CRP, involved in the down-regulation of hlyE. Moreover, PhoP-dependent hlyE up-regulation has been reported in bacteria cultured simultaneously under low pH and low concentration of Mg2+. Nevertheless, the relative contribution of each environmental signal is not completely clear. In this work we aimed to better understand the regulation of hlyE in S. Typhi and the integration of different environmental signals through global regulators. RESULTS: We found that Fis participates as a CRP-independent glucose-dependent down-regulator of hlyE. Also, Fis and CRP seem to exert the repression over hlyE through down-regulating rpoS. Moreover, PhoP up-regulates hlyE expression via rpoS under low pH and low Mg2+ conditions. CONCLUSIONS: All these results together show that, at least under the tested conditions, RpoS is the central regulator in the hlyE regulatory network, integrating multiple environmental signals and global regulators.

Stress positron emission tomography is safe and can guide coronary revascularization in high-risk patients being considered for transcatheter aortic valve replacement.

BACKGROUND: The safety and accuracy of regadenoson stress positron emission tomography (PET) in patients with significant aortic stenosis (AS) is unknown. In patients undergoing surgical aortic valve replacement, coronary artery bypass grafting for coronary artery disease is standard, but the appropriate revascularization strategy in patients undergoing TAVR is uncertain. Stress PET may identify patients that benefit from revascularization. METHODS: Fifty consecutive patients who were referred for consideration of TAVR and underwent a stress PET study were retrospectively identified. We assessed major adverse cardiac events and significant decreases in systolic blood pressure. The percentage of jeopardized myocardium was determined by combining ischemic and hibernating myocardium. RESULTS: Our patients were high risk with a mean Society of Thoracic Surgeons mortality score of 11.4% and had severe AS with a moderately reduced left ventricular ejection fraction (EF) (mean aortic valve area of 0.78 ± 0.25 cm(2) and mean EF of 39 ± 16%). There were no major adverse events during testing. Transient hypotension occurred in 16% of the patients. Revascularization was performed in 44% of patients, and 91% of these patients had revascularization to territories jeopardized on PET. These patients had substantial jeopardized myocardium (median 19%), and only 3 patients underwent revascularization despite less than 10% jeopardized myocardium. CONCLUSIONS: Stress cardiac PET with regadenoson can be performed safely in patients with severe AS. Results of the PET study can accurately direct subsequent revascularization.

Long-term results of electrical stimulation of the lower esophageal sphincter for treatment of proximal GERD.

INTRODUCTION: Electrical stimulation of the lower esophageal sphincter (LES) in gastroesophageal reflux disease (GERD) patients, using EndoStim(®) LES stimulation system (EndoStim BV, the Hague, Netherlands), enhances LES pressure, decrease distal esophageal acid exposure, improves symptoms, and eliminates the need in many patients for daily GERD medications. AIM: To evaluate, in a post hoc analysis, the effect of LES stimulation on proximal esophageal acid exposure in a subgroup of patients with abnormal proximal esophageal acid exposure. METHODS: Nineteen patients (median age 54 years; IQR 47-64; men-10) with GERD partially responsive to proton pump inhibitors (PPI), hiatal hernia ≤ 3 cm, esophagitis ≤ LA grade C underwent laparoscopic implantation of the LES stimulator. LES stimulation at 20 Hz, 215 µs, 5-8 m Amp sessions was delivered in 6-12, 30 min sessions each day. Esophageal pH at baseline and after 12-months of LES stimulation was measured 5 and 23 cm above the manometric upper border of LES. RESULTS: Total, upright and supine values of median (IQR) proximal esophageal pH at baseline were 0.4 (0.1-1.4), 0.6 (0.2-2.3), and 0 (0.0-0.2) %, respectively, and at 12 months on LES-EST were 0 (0-0) % (p = 0.001 total and upright; p = 0.043 supine comparisons). 24-hour distal esophageal acid exposure improved from 10.2 (7.6-11.7) to 3.4 (1.6-7.0) % (p = 0.001). Seven (37%) patients had abnormal (>1.1%) 24-hour proximal acid exposure at baseline; all normalized at 12 months (p = 0.008). In these 7 patients, total, upright, and supine median proximal acid exposure values at baseline were 1.7 (1.3-4.1), 2.9 (1.9-3.7), and 0.3 (0-4.9) %, respectively, and after 12 months of LES-EST were 0 (0-0.0), 0 (0-0.1), and 0 (0-0) % (p = 0.018 total and upright; p = 0.043 supine comparisons). Distal esophageal pH for this group improved from 9.3 (7.8-17.2) at baseline to 3.2 (1.1-3.7) % at 12-months (p = 0.043). There were no GI side effects such as dysphagia, gas-bloat or diarrhea or device or procedure related serious adverse events with LES-EST. There was also a significant improvement in their GERD-HRQL scores. CONCLUSION: LES-EST is associated with normalization of proximal esophageal pH in patients with GERD and may be useful in treating those with proximal GERD. The LES-EST is safe without typical side effects associated with traditional antireflux surgery.

Layer upon layer: Imaging techniques of bladder matrix stone: A case report.

Matrix lithiasis within the bladder is an extremely rare and diagnostically challenging condition, characterized by its atypical presentation and complex imaging appearance. We report the case of a 69-year-old woman with nonspecific urinary symptoms, including hematuria and abdominal pain. Initial ultrasonography revealed an echogenic lesion on the bladder wall, leading to further investigations using computed tomography (CT) and magnetic resonance imaging (MRI). CT imaging initially delineated the lesion's structure, revealing a complex, multilayered cystic mass. Subsequent MRI provided detailed insights into the internal architecture of the mass, further elucidating its layered structure. Although a parasitic etiology was initially suspected, matrix lithiasis was later confirmed. This case highlights the critical role of a comprehensive imaging strategy in diagnosing rare urological conditions and emphasizes the importance of multimodal imaging in differentiating potential diagnoses.