Clinical Imaging Modalities Research Articles

Quantitative Imaging Biomarker Ontology (QIBO) for Knowledge Representation of Biomedical Imaging Biomarkers

A widening array of novel imaging biomarkers is being developed using ever more powerful clinical and preclinical imaging modalities. These biomarkers have demonstrated effectiveness in quantifying biological processes as they occur in vivo and in the early prediction of therapeutic outcomes. However, quantitative imaging biomarker data and knowledge are not standardized, representing a critical barrier to accumulating medical knowledge based on quantitative imaging data. We use an ontology to represent, integrate, and harmonize heterogeneous knowledge across the domain of imaging biomarkers. This advances the goal of developing applications to (1) improve precision and recall of storage and retrieval of quantitative imaging-related data using standardized terminology; (2) streamline the discovery and development of novel imaging biomarkers by normalizing knowledge across heterogeneous resources; (3) effectively annotate imaging experiments thus aiding comprehension, re-use, and reproducibility; and (4) provide validation frameworks through rigorous specification as a basis for testable hypotheses and compliance tests. We have developed the Quantitative Imaging Biomarker Ontology (QIBO), which currently consists of 488 terms spanning the following upper classes: experimental subject, biological intervention, imaging agent, imaging instrument, image post-processing algorithm, biological target, indicated biology, and biomarker application. We have demonstrated that QIBO can be used to annotate imaging experiments with standardized terms in the ontology and to generate hypotheses for novel imaging biomarker-disease associations. Our results established the utility of QIBO in enabling integrated analysis of quantitative imaging data.

Nano‐Sized CT Contrast Agents

Computed tomography (CT) is one of the most widely used clinical imaging modalities. In order to increase the sensitivity of CT, small iodinated compounds are used as injectable contrast agents. However, the iodinated contrast agents are excreted through the kidney and have short circulation times. This rapid renal clearance not only restricts in vivo applications that require long circulation times but also sometimes induces serious adverse effects related to the excretion pathway. In addition, the X-ray attenuation of iodine is not efficient for clinical CT that uses high-energy X-ray. Due to these limitations, nano-sized iodinated CT contrast agents have been developed that can increase the circulation time and decrease the adverse effects. In addition to iodine, nanoparticles based on heavy atoms such as gold, lanthanides, and tantalum are used as more efficient CT contrast agents. In this review, we summarize the recent progresses made in nano-sized CT contrast agents.

Impact of 18F-Choline PET/CT in Prostate Cancer Patients with Biochemical Recurrence: Influence of Androgen Deprivation Therapy and Correlation with PSA Kinetics

We evaluated the potential of (18)F-fluoromethyldimethyl-2-hydroxyethyl-ammonium (FCH) PET/CT in the detection of recurrent disease or distant metastases and correlated its diagnostic accuracy with prostate-specific antigen (PSA) levels in prostate cancer patients with biochemical evidence of recurrence. Furthermore, the influences of androgen deprivation therapy (ADT) and its duration on (18)F-FCH PET were assessed in this study. This prospective study included 250 prostate cancer patients with PSA relapse who underwent (18)F-FCH PET/CT. At the time of (18)F-FCH PET/CT imaging, the mean PSA level was 46.9 ± 314.7 ng/mL and 55.2% (138/250) of patients were receiving ADT. Overall, ADT was performed on 67.2% (168/250) of patients after initial treatment. Imaging was performed on an integrated PET/CT system. Acquisition started 1 min after intravenous injection of (18)F-FCH (4.07 MBq/kg of body weight) with dynamic PET images in the pelvic region during 8 min (1 min/frame) followed by a static semi-whole-body acquisition. The final diagnosis of positive PET lesions was based on histopathology or a consensus of clinical findings, additional imaging, or follow-up imaging modalities. (18)F-FCH PET/CT was able to correctly detect malignant lesions in 74% (185/250) of patients but was negative in 26% (65/250). In 28% of patients, only 1 lesion was detected (69/250); from these, 65.2% (45 patients) had a local recurrence, 18.8% (13 patients) a single lymph node, and 15.9% (11 patients) a solitary bone metastasis. The sensitivity of the (18)F-FCH PET was significantly higher (P = 0.001) in patients with ongoing ADT (85%; confidence interval, 80%-91%) than in patients without ADT (59.5%; confidence interval, 50%-69%). (18)F-FCH PET sensitivity was 77.5%, 80.7%, 85.2%, and 92.8% for the trigger PSA levels of more than 0.5, 1.0, 2.0, and 4.0 ng/mL, respectively. Scan sensitivity was 33% in patients with a trigger PSA level of less than 0.3 ng/mL and 77% in patients with a trigger PSA level of greater than 0.3 ng/mL, respectively (P = 0.001). Using a binary logistic regression analysis model, we showed trigger PSA and ADT to be the only significant predictors of positive PET findings. (18)F-FCH PET/CT proved its potential as a noninvasive 1-stop diagnostic modality enabling us to correctly detect occult disease in 74% of patients and to differentiate localized from systemic disease. In patients with biochemical recurrence, it also guides to an optimal treatment approach after initial treatment. Trigger PSA and ADT are the 2 significant predictors of (18)F-FCH-positive PET lesions. ADT seems not to impair (18)F-FCH uptake in hormone-refractory prostate cancer patients.

Magnetic resonance imaging of microvessels using iron-oxide nanoparticles

The visualization of microstructures including blood vessels with an inner overall cross-sectional area below approximately 200 μm remains beyond the capabilities of current clinical imaging modalities. But with magnetic resonance (MR) imaging, magnetic entities cause susceptibility artifacts in the images by disrupting the homogeneous magnetic field in a much larger scale than their actual size. As validated in this paper through simulation and in-vitro experiments, these artifacts can serve as a source of contrast, enabling microvessels with an inner diameter below the spatial resolution of any medical imaging modalities to be visualized using a clinical MR scanner. For such experiments, micron-sized agglomerations of iron-oxide (Fe3O4) nanoparticles were injected in microchannels with internal diameters of 200 and 50 μm equivalent to a narrower artery or a larger arteriole, and down to a smaller arteriole, respectively. The results show the feasibility of the proposed method for micro-particle detection and the visualization of microvessels using a 1.5 T clinical MR scanner. It was confirmed that the method is reproducible and accurate at the sub-pixel level.

The need for performance standards in clinical translation and adoption of fluorescence molecular imaging

The need for performance standards in clinical translation and adoption of fluorescence molecular imaging

The effect of patient-specific annular motion on dynamic simulation of mitral valve function

Most surgical procedures for patients with mitral regurgitation (MR) focus on optimization of annular dimension and shape utilizing ring annuloplasty to restore normal annular geometry, increase leaflet coaptation, and reduce regurgitation. Computational studies may provide insight on the effect of annular motion on mitral valve (MV) function through the incorporation of patient-specific MV apparatus geometry from clinical imaging modalities such as echocardiography. In the present study, we have developed a novel algorithm for modeling patient-specific annular motion across the cardiac cycle to further improve our virtual MV modeling and simulation strategy. The MV apparatus including the leaflets, annulus, and location of papillary muscle tips was identified using patient 3D echocardiography data at end diastole and peak systole and converted to virtual MV model. Dynamic annular motion was modeled by incorporating the ECG-gated time-varying scaled annular displacement across the cardiac cycle. We performed dynamic finite element (FE) simulation of two sets of patient data with respect to the presence of MR. Annular morphology, stress distribution across the leaflets and annulus, and contact stress distribution were determined to assess the effect of annular motion on MV function and leaflet coaptation. The effect of dynamic annular motion clearly demonstrated reduced regions with large stress values and provided an improved accuracy in determining the location of improper leaflet coaptation. This strategy has the potential to better quantitate the extent of pathologic MV and better evaluate functional restoration following MV repair.

CRT-4 Multi-center, First-in-man Evaluation Of The Myolimus-eluting Bioresorbable Coronary Scaffold: 6-month Clinical And Imaging Results

To evaluate the clinical safety and effectiveness of the DESolve™ Myolimus-Eluting Bioresorbable Coronary Scaffold (BCSS)in patients with single de novo native coronary artery lesions through clinical endpoints and multiple imaging modalities. Background: The DESolve BCSS is a novel drug eluting

Optoacoustic Multispectral Imaging of Radiolucent Foreign Bodies in Tissue

Optoacoustic imaging is an emerging medical technology that uniquely combines the absorption contrast of optical imaging and the penetration depth of ultrasound. While it is not currently employed as a clinical imaging modality, the results of current research strongly support the use of optoacoustic-based methods in medical imaging. One such application is the diagnosis of the presence of soft tissue foreign bodies. Because many radiolucent foreign bodies have sufficient contrast for imaging in the optical domain, laser-induced optoacoustic imaging could be advantageous for the detection of such objects. Common foreign bodies have been scanned over a range of visible and near infrared wavelengths by using an optoacoustic method to obtain the spectroscopic properties of the materials commonly associated with these foreign bodies. The derived optical absorption spectra compared quite closely to the absorption spectra generated when using a conventional spectrophotometer. By using the probe-beam deflection technique, a novel, pressure-wave detection method, we successfully generated optoacoustic spectroscopic plots of a wooden foreign body embedded in a tissue phantom, which closely resembled the spectrum of the same object obtained in isolation. A practical application of such spectra is to assemble a library of spectroscopic data for radiolucent materials, from which specific characteristic wavelengths can be selected for use in optimizing imaging instrumentation and provide a basis for the identification of the material properties of particular foreign bodies.

Unresectable Carcinoma Pancreas

Background: At the time of diagnosis most of pancreatic cancer is in the advanced stage and curative resection becomes impossible. These inoperable diseases are labeled as “uresectable carcinonma pancreas.” Accurate and early assessment is essential for such patients to gain a better outcome. Objective: This study was carried out to evaluate clinical presentations, laboratory investigations, histopa­thology and imaging modalities used to diagnose and label pancreatic carcinoma as unresectable. Methods: This retrospective study was carried out from July 2004 to June 2006 in BIRDEM Hospital, Dhaka. After careful scrutiny of clinical pres­entation, laboratory imaging studies, tissue diagnosis, tumor markers and operative findings it was seen that 50 patients (sample size n = 50) were labeled as unresectable carcinoma pancreas. Male patients were 28 ( n 1 = 28) and female patients were 22 ( n 2 = 22). Chi-square (χ 2 ) test was applied and P value <0.01 was considered as significant. Result: Most (72%) of the unresectable carcinoma pancreas patients presented with weight loss and obstructive jaundice. Laboratory study and ultrasonography (USG) were carried out in all patients ( n = 50). Computerized tomography (CT) scan was done in 45 patients, magnetic reso­nance imaging (MRI) in 8 patients, endoscopic retrograde cholangiopancreatog­raphy (ERCP) in 20 patients and upper gastrointestinal (UGI) contrast was carried out in 10 patients. Preoperative biopsy was taken from 25 patients. Most of the patients presented with abnormal liver functions and raised tumor markers. Three patients had mild renal impairment. USG was able to diagnose 84% patients with pancreatic carcinoma and could delineate features of unresectibility in 69% patients. CT scan diagnosed 90% patients with pancreatic carcinoma and outlined the features of unresectibility in 84.44% patients. ERCP was able to diagnose 13 (65%) patients as carcinoma pancreas but failed to delineate the features of unre­sectibility in any of the patients. UGI contrast was able to diagnose only 10% unresectable pancreatic carcinoma. MRI was 100% accurate in delineating unre­sectable carcinoma pancreas. Preoperative tissue diagnosis was 88% sensitive in diagnosing pancreatic carcinoma. Conclusion: Presentation of unresectable carcinoma pancreas was obvious in most cases. Laboratory studies were of great help. Multimodal preoperative imagings were 87.5% accurate in diagnosing unre­sectable carcinoma pancreas. Tissue diagnosis was important as all the lesions were not pancreatic cancer. DOI: http://dx.doi.org/10.11566/cmoshmcj.v12i1.22 Chatt Maa Shi Hosp Med Coll J 2013; 12(1): 18-24

Abstract 18819: Multi-Center, First-In-Man Evaluation of the Myolimus-Eluting Bioresorbable Coronary Scaffold: 6-Month Clinical and Imaging Results

Aims: To evaluate the clinical safety and effectiveness of the DESolve™ Myolimus-Eluting Bioresorbable Coronary Scaffold (DESolve) in patients with single de novo native coronary artery lesions through clinical endpoints and multiple imaging modalities. Methods and Results: Background: The DESolve Bioresorbable Scaffold is a novel drug eluting device that combines a PLLA-based scaffold coated with a bioresorbable polylactide-based polymer and the drug Myolimus. Myolimus, a macrocyclic lactone mTOR inhibitor has demonstrated potent anti-proliferative properties in two First-in-Man (FIM) trials using Elixir’s metallic Myolimus-eluting coronary stents. The drug dose is 3 mcg per mm of scaffold length; the same dose as used as in the FIM studies. Sixteen patients with single, de novo coronary artery lesions were enrolled in this prospective, multi-center, single-arm FIM study. One patient did not receive a study stent and was deregistered. The 15 remaining patients are being analysed for multiple clinical endpoints: Device and Procedure Success; Major Adverse Cardiac Events (MACE), a composite endpoint of cardiac death, target vessel MI, and clinically-indicated target lesion revascularization (CI-TLR); clinically-indicated Target Lesion and Target Vessel Revascularization, (CI-TVR) and stent thrombosis assessed at 1, 6 and 12 months and annually to 5 years. Multiple assessments by angiographic, IVUS and OCT at 6 months were completed. An additional analysis using multislice computed tomography (MSCT) will be completed at 12 and 24 months. At 6 months, the in-scaffold late lumen loss was 0.19 ± 0.19 by QCA, the % volume obstruction was 7.18 ± 3.37 by IVUS, and by OCT 98.68 ± 2.44% of struts were demonstrated as covered. There was one MACE, event, a TLR, during the follow-up period. Detailed clinical and imaging results through 6 months will be presented. Conclusion: The DESolve™ Myolimus-Eluting Bioresorbable Coronary Scaffold demonstrated both excellent safety and effectiveness in this FIM study, thus warranting further clinical evaluation of the novel technology in larger clinical studies. Detailed clinical and imaging results through 6 months will be presented.

Abstract 19187: Sublingual Glycocalyx Measurement, a Novel Non-Invasive Technique to Predict Coronary Artery Disease

Background: A relatively thick endothelial lining, known as the glycocalyx (GC), forms the true interface between flowing blood and the vascular wall. The GC regulates several key endothelial functions including vascular permeability, coagulation and inflammation and contributes to the protection against atherogenic challenges. In healthy blood vessels, the GC provides limited access to flowing red blood cells (RBC). Recent observations have suggested that RBCs penetrate deeper into a damaged GC and therefore may serve as a marker for GC damage, which has been associated with microcirculatory dysfunction that accompanies, among others, coronary artery disease (CAD). Aim: In the present study we tested whether the presence of CAD could be predicted by measuring the dimension of the RBC perfused boundary region (PBR), which fills up the space between median RBC column width (MCW) and the outer edge of RBC permeable vascular lumen. In healthy blood vessels PBR is relatively small due to limited penetration of RBC into the GC and it is hypothesized that PBR will increase for a given MCW when GC is damaged. Method: We used sidestream dark field imaging, a novel stroboscopic LED ring-based clinical imaging modality, of the sublingual microvasculature in subjects with (N=10) and without (N=10, controls) angiographic CAD. From these images, MCW and PBR were determined in over 3000 vascular segments (vessel diameter between 10 and 20µm) per subject. Results: CAD patients displayed a significant increase in PBR compared to controls. The mean PBR increased from 2.31 ± 0.09µm to 2.64 ± 0.11µm (P&lt;0.05) comparing controls with CAD patients, respectively, consistent with a 0.3 µm deeper penetration of RBCs into the GC. Conclusion: These data demonstrate that CAD patients have a significant increase in the width of the RBC accessible component of the sublingual microvascular GC compared to control subjects. A wider permeable portion of the GC indicates a change in GC structure which may be associated with a reduced vascular protective function of the GC. Moreover, SDF imaging might provide a novel, noninvasive method to detect CAD.

Gene Expression Profiling (GEP) in MGUS and AMM: Predictors of Progression.

AbstractAbstract 2933Monoclonal gammopathy of undetermined significance (MGUS), a premalignant plasma cell dyscrasia, is differentiated from asymptomatic multiple myeloma (AMM), based on the level of monoclonal immunoglobulin (M spike) and bone marrow plasma cell infiltration (M spike > 3 g/dl and/or marrow plasmacytosis >10% in AMM). MGUS progresses to active Multiple Myeloma (MM) at a rate of 1–2% per year, thus imparting an average risk of 25% of progression over a lifetime. No single clinical variable, imaging modality or molecular study has yet been identified to predict progression. As a part of SWOG observational trial S0120, 262 patients were enrolled at MIRT and their GEP of purified plasma cells (PC) prospectively obtained. Here we report the results of GEP as predictor of progression. Among those with baseline GEP data available, 127 were non-IgM, AMM or MGUS and were otherwise eligible for the study. Baseline samples were restricted to those samples taken no more than 6 months prior to or 14 days following registration to S0120. If a patient had multiple baseline samples, then the sample taken closest to the patient’s registration date was used. GEP studies were performed to assign molecular classification and risk scores, along with GEP-derived amp1q21, delTP53, DKK1 and other variables. With a follow-up of 36 months in the subset with evaluable GEP baseline data in 40 MGUS and 87 AMM cases, GEP characteristics were compared with those of untreated MM patients treated with TT2, TT3, TT4, and TT5 protocols, in the context of normal donor PC signatures. Comparing MGUS with AMM, CD-2 molecular subgroup was over-represented in MGUS and HY in AMM. PSMD4 on chromosome 1q21 was also linked to AMM. In terms of GEP-70 risk model, 36% of AMM and 15% of MGUS had scores exceeding -0.26. Univariate predictors for treatment-requiring MM included the well-known serum-M and bone marrow PC variables, and GEP-70 score >-0.26 (HR=8.82, p<0.001). Whole bone marrow biopsy (BMB) GEP samples from MGUS/AMM were available in 26 samples. Applying a BMB-65 model distinguishing MM-BMB from NL-BMB (normal donors) and MGUS/AMM-BMB, we observed that there was a strong trend for delayed MM progression when MGUS/AMM-BMB scores were in the top tertile (most NL-like). Independent validation data will be presented. [Display omitted] Disclosures:Dhodapkar:Celgene: Research Funding; KHK: Research Funding.

Comment on “Emphysematous Infections of the Prostate and Scrotum in an Older Adult in a Nursing Home”

We would like to thank Dr. Cheung and Dr. Tsang1 for sharing their interesting case report, “Emphysematous Infections of the Prostate and Scrotum in an Older Adult in a Nursing Home,” in which they reported a rare case of emphysematous infection (EI) of the prostate and scrotum occurring in an older adult in a nursing home. This is the first reported case in the English literature of EI of the prostate and the scrotum with abscess formation. The patient had multiple morbid conditions and was chronically bedridden. He was admitted to a nursing home for long-term care. As mentioned in the case report, the individual was referred to the emergency department of Far Eastern Memorial Hospital, where, upon physical examination, he was found to have an enlarged scrotum with some skin discoloration (Figure 1). We think that the healthcare workers at the nursing home were responsible for the delayed referral to the hospital, because they should have been alert to such clinical manifestation during diaper changes for this individual. We agree that older residents in nursing homes are at risk of infection because of physiological changes, aging, underlying chronic diseases, poor institutional environment, impaired cognition of most older adults in terms of addressing their basic hygienic needs, difficulties in diagnosis of some infections with subtle presentations, presence of comorbid conditions obscuring the symptoms of infection, and lack of on-site diagnostic facilities.2, 3 The diagnosis of emphysematous prostatic and scrotal abscesses is based on clinical history, physical examination, and imaging modalities. The authors should present the educational image (Figure 1) of such clinical signs. Computed tomography of the pelvis is the medical imaging of choice for confirming its diagnosis.4 To reduce the morbidity and mortality of EI of the prostate and scrotum, early detection in the nursing home, aggressive surgical and medical management using appropriate broad-spectrum antibiotics, and good blood glucose control are mandatory. We agree that EI of the genitourinary tract is a life-threatening condition requiring aggressive surgical management and antibiotic therapy and is usually related to diabetes mellitus.5 The reporting authors should emphasize using appropriate broad-spectrum antibiotics. We think that this condition is related to lower urinary tract infection (UTI), especially in elderly adults with comorbidities. Surgical drainage of emphysematous prostatic abscesses can be done using a transrectal, transperineal, or transurethral approach.6 In individuals with diabetes mellitus, the gas formed is usually carbon dioxide, which results from a high concentration of sugar that bacteria ferment in the urine or tissues.7 Like emphysematous cystitis and emphysematous pyelonephritis, EI of the prostate and scrotum is a rare complication of UTI that can easily progress to a life-threatening condition and cause a prolonged hospital stay. Conflict of Interest: The editor in chief has reviewed the conflict of interest checklist provided by the authors and has determined that the authors have no financial or any other kind of personal conflicts with this paper. Author Contributions: Concept and design: Min-Po Ho. Acquisition of participant and data: Kaung-Chau Tsai, Min-Po Ho. Analysis and interpretation of data: Kaung-Chau Tsai, Min-Po Ho. Preparation of manuscript: Min-Po Ho. Critical review and approval: Kaung-Chau Tsai, Min-Po Ho. Sponsor's Role: None.

Reduced corticomotor excitability and motor skills development in children born preterm

The mechanisms underlying the altered neurodevelopment commonly experienced by children born preterm, but without brain lesions, remain unknown. While individuals born the earliest are at most risk, late preterm children also experience significant motor, cognitive and behavioural dysfunction from school age, and reduced income and educational attainment in adulthood. We used transcranial magnetic stimulation and functional assessments to examine corticomotor development in 151 children without cerebral palsy, aged 10-13 years and born after gestations of 25-41 completed weeks. We hypothesized that motor cortex and corticospinal development are altered in preterm children, which underpins at least some of their motor dysfunction. We report for the first time that every week of reduced gestation is associated with a reduction in corticomotor excitability that remains evident in late childhood. This reduced excitability was associated with poorer motor skill development, particularly manual dexterity. However, child adiposity, sex and socio-economic factors regarding the child's home environment soon after birth were also powerful influences on development of motor skills. Preterm birth was also associated with reduced left hemisphere lateralization, but without increasing the likelihood of being left handed per se. These corticomotor findings have implications for normal motor development, but also raise questions regarding possible longer term consequences of preterm birth on motor function.

Gadolinium‐based contrast agents for magnetic resonance cancer imaging

AbstractMagnetic resonance imaging (MRI) is a clinical imaging modality effective for anatomical and functional imaging of diseased soft tissues, including solid tumors. MRI contrast agents (CA) have been routinely used for detecting tumor at an early stage. Gadolinium‐based CA are the most commonly used CA in clinical MRI. There have been significant efforts to design and develop novel Gd(III) CA with high relaxivity, low toxicity, and specific tumor binding. The relaxivity of the Gd(III) CA can be increased by proper chemical modification. The toxicity of Gd(III) CA can be reduced by increasing the agents' thermodynamic and kinetic stability, as well as optimizing their pharmacokinetic properties. The increasing knowledge in the field of cancer genomics and biology provides an opportunity for designing tumor‐specific CA. Various new Gd(III) chelates have been designed and evaluated in animal models for more effective cancer MRI. This review outlines the design and development, physicochemical properties, and in vivo properties of several classes of Gd(III)‐based MR CA tumor imaging. WIREs Nanomed Nanobiotechnol 2013, 5:1–18. doi: 10.1002/wnan.1198This article is categorized under: Diagnostic Tools &gt; Biosensing Diagnostic Tools &gt; In Vivo Nanodiagnostics and Imaging

TCT-563 Multi-Center, First-In-Man Evaluation of the Myolimus-Eluting Bioresorbable Coronary Scaffold: 6-Month Clinical and Imaging Results

To evaluate the clinical safety and effectiveness of the DESolve™ Myolimus-Eluting Bioresorbable Coronary Scaffold (BCSS)in patients with single de novo native coronary artery lesions through clinical endpoints and multiple imaging modalities. The DESolve BCSS is a novel drug eluting device that

Thrombolysis in Acute Pulmonary Thromboembolism

Acute pulmonary embolism (PE) is a common clinical condition with presentations that may vary from asymptomatic subsegmental emboli to massive vascular obstruction and shock with high risk of death. Identifying patients at highest risk for death is critical to select those who would benefit most from thrombolytic therapy. New and evolving clinical prediction models, serum tests, and imaging modalities are being used to improve our ability to identify potential thrombolytic candidates. We review the evolution of the present guidelines on the management of PE, specifically regarding the evolving role of thrombolytics; outcomes following thrombolytic therapy, including mortality, hemorrhage, hemodynamic improvement, and prevention of chronic thromboembolic pulmonary hypertension; and our strategy for risk stratification of pulmonary embolism.

Recent Advances in Optical Mammography

Diffuse optical imaging (DOI) techniques provide a non-invasive, low cost and sensitive method for assessing the functional state of the human breast. Several studies undertaken in recent years with the objective of investigating the clinical applications of diffuse optical methods, demonstrate the potential of the technique for screening for breast cancer, associated risk factors and for monitoring the efficacy of therapeutic regimen post-diagnosis. In this review, the different diffuse optical methods and instrumentation used in the functional imaging of the breast are described and the results of the clinical studies of the healthy and diseased breast are provided. Moreover, the application of optical imaging in moni- toring neo-adjuvant chemotherapy is summarized, the role of alternate contrast mechanisms in optical imaging is outlined and lastly, the role of optical imaging in multimodal imaging - wherein optical imaging is combined with existing clinical imaging modalities providing complementary diagnostic information - is discussed.

Extra-articular diffuse-type giant cell tumour of the temporomandibular joint

Diffuse-type giant cell tumour (DTGCT) is a benign but destructive proliferative disorder of the synovium of joint capsules, tendons and bursae. Lesions originating from the articular synovium may grow intra-articularly or expand widely extra-articularly. Rare cases may develop only in peri-articular tissues. Temporomandibular joint (TMJ) involvement is exceptional and only two cases of purely extra-articular TMJ-DTGCT have been reported. The authors report an additional case of extra-articular TMJ-DTGCT. The clinical features, histopathological characteristics, imaging modalities and diagnostic methods for DTGCT are discussed together with a literature review based on the clinical aspects of TMJ involvement.

Measuring Fibrosis: Is Seeing Really Believing?

Chronic liver disease is a rising global health problem. However, despite vast advances in medical technology, liver biopsy remains the gold standard in assessing disease severity [1]. Biopsy was historically utilized solely for diagnostic purposes; however, with the advent of therapeutic options, biopsy is now additionally utilized in therapeutic decision making and determining prognosis. However, the procedure itself is not without complications and limitations, and patients are reluctant to undergo multiple biopsies during treatment. This has fueled efforts in developing non-invasive methods to measure fibrosis. Early detection of fibrosis allows for identification of patients who require therapy to prevent evolution to cirrhosis. In a recent systematic review by Smith and Sterling [2], non-invasive methods (clinical demographics, serum biomarkers, imaging modalities, breath tests, and complex models) used either alone or in combination were reported. Many non-invasive measures are shown to detect cirrhosis, but are not established in differentiating between stages of fibrosis. Each seems to have its own advantages and disadvantages. Of the imaging techniques, ultrasound holds the most promise due to its widespread availability. Ultrasound-Based Measures of Fibrosis