Schistosomiasis mansoni in low transmission areas: abdominal ultrasound

In endemic areas with low prevalence and low intensity of infection, the diagnosis of hepatic pathology due to the Schistosoma mansoni infection is very difficult. In order to establish the hepatic morbidity, a double-blind study was achieved in Venezuelan endemic areas, with one group of patients with schistosomiasis and the other one of non-infected people, that were evaluated clinically and by abdominal ultrasound using the Cairo classification. Schistosomiasis diagnosis was established based on parasitologic and serological tests. The increase of the hepatic size at midclavicular and midsternal lines (in hepatometry) and the hard liver consistency were the clinical parameters able to differentiate infected persons from non infected ones, as well as the presence of left lobe hepatomegaly detected by abdominal ultrasound. The periportal thickening, especially the mild form, was frequent in all age groups in both infected and uninfected patients. There was not correlation between the intensity of infection and ultrasound under the current circumstances. Our data suggest that in Venezuela, a low endemic area of transmission of schistosomiasis, the hepatic morbidity is mild and uncommon. The Cairo classification seems to overestimate the prevalence of periportal pathology. The specificity of the method must be improved, especially for the recognition of precocious pathology. Other causes of hepatopathies must be investigated.

Ultrasound Biomicroscopy Evaluation of Anterior Extension of Retinoblastomas : A Clinico-Pathological Study

Purpose: Extension of retinoblastoma cells anterior to the vitreous surface is a criteria used to categorize retinoblastomas in Group E. In some cases, the assessment of anterior chamber invasion is readily visible by slit lamp examination, but in other cases, invasion of the posterior chamber is clinically difficult to determinate. Ultrasound biomicroscopy (UBM) allows high-resolution images of the anterior segment and structures normally hidden from clinical visualization such as ciliary body, zonule or posterior chamber. This prompted us to evaluate the value of UBM in the assessment of posterior and anterior chamber involvement in patients with peripheral extending retinoblastomas. Methods: We retrospectively reviewed all retinoblastoma cases that underwent enucleation in our institution from 1.1996 till 12.2009 in which UBM ( 35-MHz or 50-MHz) evaluation was available. The UBM results were compared with the histopathological data. Results: From 1.1996 till 12.2009, 146 enucleations were performed in our institution. UBM information was available in 18 cases. There were 8 males and 10 females. The mean age was 4 years old. UBM allowed correct assessement of posterior chamber invasion in 15 cases (13 cases with retinoblastoma in the posterior chamber and 2 cases without retinoblastoma in the posterior chamber). There was a significant correlation between the presence of retinoblastoma cells in the posterior chamber detected by UBM and the histopathological confirmation of posterior chamber involvement (p=0,0008). The sensitivity of UBM in the assessment of posterior chamber invasion by retinoblastoma was 81% and the specificity 100%. UBM allowed correct assessment of anterior chamber invasion in 13 cases. The sensitivity of UBM for this purpose was 50% and the specificity 60 %. Conclusions: In selected cases of advanced retinoblastoma, UBM appears to represent a valuable tool in the evaluation of the precise extension of the disease. Although our series encompasses only a limited number of cases, the sensitivity and specificity of UBM in the assessment of retinoblastoma anterior extension is interesting. Further prospective multi-centered clinical studies would be necessary to better delineate the utility of this method in the precise categorization of retinoblastoma anterior extension

Effect of Platinum-Based Chemoradiotherapy on Cellular Proliferation in Bone Marrow and Spleen, Estimated by 18F-FLT PET/CT in Patients with Locally Advanced Non-Small Cell Lung Cancer.

Historically, it has been difficult to monitor the acute impact of anticancer therapies on hematopoietic organs on a whole-body scale. Deeper understanding of the effect of treatments on bone marrow would be of great potential value in the rational design of intensive treatment regimens. 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) is a functional radiotracer used to study cellular proliferation. It is trapped in cells in proportion to thymidine-kinase 1 enzyme expression, which is upregulated during DNA synthesis. This study investigates the potential of (18)F-FLT to monitor acute effects of chemotherapy on cellular proliferation and its recovery in bone marrow, spleen, and liver during treatment with 2 different chemotherapy regimens.

Pancreatic trauma in children.

We identified two distinct groups of patients in the 91 documented cases of pancreatic trauma (median age 8.0 years, range 0.6-15.8 years; M:F 2.5:1.0): 59 had a history of abdominal trauma and elevated serum lipase but no CT or ultrasound evidence of pancreatic injury (Group A); 32 had a history of abdominal trauma, elevated serum lipase but also had CT scan and/or ultrasound evidence of pancreatic injury (Group B). Patients with "less severe" injury based on normal imaging had a lower initial lipase level [Group A, median 651 U/L (interquartile range 520-1,324) vs. Group B, 1,608 U/L (interquartile range 680-3,526); p = 0.005] and shorter admission time [Group A, 9.0 days (interquartile range 5.5-15.5) vs. Group B, 13.4 days (interquartile range 6.8-23.8); p = 0.04]. There were no differences with respect to mortality (Group A, 13.5% vs. Group B, 12.5%), but patients with evidence of injury on imaging were more likely to have surgical intervention (p = 0.0001). The single most important overall cause of pancreatic trauma was involvement in a motor vehicle accident as a passenger or pedestrian. However, in children with high-grade ductal injury, bicycle handlebar injuries were most common. Associated injuries were common in both groups.

Ultrasound-guided suprascapular nerve block, description of a novel supraclavicular approach.

BACKGROUND AND OBJECTIVES: The suprascapular nerve (SSN) block is frequently performed for different shoulder pain conditions and for perioperative and postoperative pain control after shoulder surgery. Blind and image-guided techniques have been described, all of which target the nerve within the supraspinous fossa or at the suprascapular notch. This classic target point is not always ideal when ultrasound (US) is used because it is located deep under the muscles, and hence the nerve is not always visible. Blocking the nerve in the supraclavicular region, where it passes underneath the omohyoid muscle, could be an attractive alternative. METHODS: In the first step, 60 volunteers were scanned with US, both in the supraclavicular and the classic target area. The visibility of the SSN in both regions was compared. In the second step, 20 needles were placed into or immediately next to the SSN in the supraclavicular region of 10 cadavers. The accuracy of needle placement was determined by injection of dye and following dissection. RESULTS: In the supraclavicular region of volunteers, the nerve was identified in 81% of examinations (95% confidence interval [CI], 74%-88%) and located at a median depth of 8 mm (interquartile range, 6-9 mm). Near the suprascapular notch (supraspinous fossa), the nerve was unambiguously identified in 36% of examinations (95% CI, 28%-44%) (P < 0.001) and located at a median depth of 35 mm (interquartile range, 31-38 mm; P < 0.001). In the cadaver investigation, the rate of correct needle placement of the supraclavicular approach was 95% (95% CI, 86%-100%). CONCLUSIONS: Visualization of the SSN with US is better in the supraclavicular region as compared with the supraspinous fossa. The anatomic dissections confirmed that our novel supraclavicular SSN block technique is accurate.

Cardiac CT: practical approach to integrate appropriate indications in daily practice.

Recent advances in CT technologies had significantly improved the clinical utility of cardiac CT. Major efforts have been made to optimize the image quality, standardize protocols and limit the radiation exposure. Rapid progress in post-processing tools dedicated not only to the coronary artery assessment but also to the cardiac cavities, valves and veins extended applications of cardiac CT. This potential might be however used optimally considering the current appropriate indications for use as well as the current technical imitations. Coronary artery disease and related ischemic cardiomyopathy remain the major applications of cardiac CT and at the same time the most complex one. Integration of a specific knowledge is mandatory for optimal use in this area for asymptomatic as for symptomatic patients, with a specific regards to patient with acute chest pain. This review aimed to propose a practical approach to implement appropriate indications in our routine practice. Emerging indications and future direction are also discussed. Adequate preparation of the patient, training of physicians, and the multidisciplinary interaction between actors are the key of successful implementation of cardiac CT in daily practice.

Extent of hypoattenuation on CT angiography source images in basilar artery occlusion: prognostic value in the Basilar Artery International Cooperation Study.

BACKGROUND AND PURPOSE: The posterior circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS) quantifies the extent of early ischemic changes in the posterior circulation with a 10-point grading system. We hypothesized that pc-ASPECTS applied to CT angiography source images predicts functional outcome of patients in the Basilar Artery International Cooperation Study (BASICS). METHODS: BASICS was a prospective, observational registry of consecutive patients with acute symptomatic basilar artery occlusion. Functional outcome was assessed at 1 month. We applied pc-ASPECTS to CT angiography source images of patients with CT angiography for confirmation of basilar artery occlusion. We calculated unadjusted and adjusted risk ratios (RRs) of pc-ASPECTS dichotomized at ≥8 versus <8. Primary outcome measure was favorable outcome (modified Rankin Scale scores 0-3). Secondary outcome measures were mortality and functional independence (modified Rankin Scale scores 0-2). RESULTS: Of 158 patients included, 78 patients had a CT angiography source images pc-ASPECTS≥8. Patients with a pc-ASPECTS≥8 more often had a favorable outcome than patients with a pc-ASPECTS<8 (crude RR, 1.7; 95% CI, 0.98-3.0). After adjustment for age, baseline National Institutes of Health Stroke Scale score, and thrombolysis, pc-ASPECTS≥8 was not related to favorable outcome (RR, 1.3; 95% CI, 0.8-2.2), but it was related to reduced mortality (RR, 0.7; 95% CI, 0.5-0.98) and functional independence (RR, 2.0; 95% CI, 1.1-3.8). In post hoc analysis, pc-ASPECTS dichotomized at ≥6 versus <6 predicted a favorable outcome (adjusted RR, 3.1; 95% CI, 1.2-7.5). CONCLUSIONS: pc-ASPECTS on CT angiography source images independently predicted death and functional independence at 1 month in the CT angiography subgroup of patients in the BASICS registry.

Molecular imaging by micro-CT: specific E-selectin imaging.

The primary goal of this study was to design a fluorescent E-selectin-targeted iodine-containing liposome for specific E-selectin imaging with the use of micro-CT. The secondary goal was to correlate the results of micro-CT imaging with other imaging techniques with cellular resolution, i.e., confocal and intravital microscopy. E-selectin-targeted liposomes were tested on endothelial cells in culture and in vivo in HT-29 tumor-bearing mice (n = 12). The liposomes contained iodine (as micro-CT contrast medium) and fluorophore (as optical contrast medium) for confocal and intravital microscopy. Optical imaging methods were used to confirm at the cellular level, the observations made with micro-CT. An ischemia-reperfusion model was used to trigger neovessel formation for intravital imaging. The E-selectin-targeted liposomes were avidly taken up by activated endothelial cells, whereas nontargeted liposomes were not. Direct binding of the E-selectin-targeted liposomes was proved by intravital microscopy, where bright spots clearly appeared on the activated vessels. Micro-CT imaging also demonstrated accumulation of the targeted lipsomes into subcutaneous tumor by an increase of 32 +/- 8 HU. Hence, internalization by activated endothelial cells was rapid and mediated by E-selectin. We conclude that micro-CT associated with specific molecular contrast agent is able to detect specific molecular markers on activated vessel walls in vivo.

Techniques for CT and MR, post-processing, radiation

Brain perfusion can be assessed by CT and MR. For CT, two major techniques are used. First, Xenon CT is an equilibrium technique based on a freely diffusible tracer. First pass of iodinated contrast injected intravenously is a second method, more widely available. Both methods are proven to be robust and quantitative, thanks to the linear relationship between contrast concentration and x-ray attenuation. For the CT methods, concern regarding x-ray doses delivered to the patients need to be addressed. MR is also able to assess brain perfusion using the first pass of gadolinium based contrast agent injected intravenously. This method has to be considered as a semi-quantitative because of the non linear relationship between contrast concentration and MR signal changes. Arterial spin labeling is another MR method assessing brain perfusion without injection of contrast. In such case, the blood flow in the carotids is magnetically labelled by an external radiofrequency pulse and observed during its first pass through the brain. Each of this various CT and MR techniques have advantages and limits that will be illustrated and summarized.Learning Objectives:1. To understand and compare the different techniques for brain perfusion imaging.2. To learn about the methods of acquisition and post-processing of brain perfusion by first pass of contrast agent for CT and MR.3. To learn about non contrast MR methods (arterial spin labelling).