Comparison of similarity measures for the task of template matching of masses on serial mammograms

We conducted a study to evaluate the effectiveness of twelve different similarity measures in matching the corresponding masses on temporal pairs of current and prior mammograms. To perform this comparison we implemented each of the twelve similarity measures in the final stage of our multistage registration technique for automated registration of breast lesions in serial mammograms. The multistage technique consists of three stages. In the first stage an initial fan-shape search region was estimated on the prior mammogram based on the geometrical position of the mass on the current mammogram. In the second stage, the location of the fan-shape region was refined by warping, based on an affine transformation and simplex optimization. A new refined search region was defined on the prior mammogram. In the third stage, a search for the best match between the lesion template from the current mammogram and a structure on the prior mammogram was carried out within the search region. Our data set consisted of 318 temporal pairs. We performed three experiments, using a different subset of the 318 temporal pairs for each experiment. In each experiment we further tested how the performance of the similarity measures varied as the size of the search region increased or decreased. We evaluated the twelve similarity measures based on four criteria. The first criterion was the mean Euclidean distance, which was the average distance of the true location of the mass to the location detected by the similarity measure. The second criterion was the percentage of temporal pairs that were aligned so that 50% or more of the lesion area overlapped. The third criterion was the percentage of pairs that were aligned so that 75% or more of the lesion area overlapped. The fourth and final criterion was the robustness of the similarity measure. Our results showed that three of the similarity measures, Pearson's correlation, the cosine coefficient, and Goodman and Kruskal's Gamma coefficient, provide significantly higher accuracy (p < 0.05) in the task of matching the corresponding masses on serial mammograms than the other nine similarity measures.     

Subglottic cysts in a patient with recurrent stridor and respiratory distress

Subglottic cysts are rare causes of stridor in infancy and should be suspected in the case of intubation. A 15-month-old male presented with recurrent stridor and respiratory distress. Prematurity and intubation were present in his history. Two subglottic cysts below the glottis were diagnosed. The cysts were ruptured by flexible bronchoscopy. The child's stridor and other symptoms disappeared thereafter. Early diagnosis of subglottic cysts is important since the obstruction can be relieved by rupturing the cysts with bronchoscope, whereas development of a fibrotic stenosis may require a tracheotomy, with its attending morbidity.     

Lung nodule detection on thoracic computed tomography images: preliminary evaluation of a computer-aided diagnosis system

We are developing a computer-aided diagnosis (CAD) system for lung nodule detection on thoracic helical computed tomography (CT) images. In the first stage of this CAD system, lung regions are identified by a k-means clustering technique. Each lung slice is classified as belonging to the upper, middle, or the lower part of the lung volume. Within each lung region, structures are segmented again using weighted k-means clustering. These structures may include true lung nodules and normal structures consisting mainly of blood vessels. Rule-based classifiers are designed to distinguish nodules and normal structures using 2D and 3D features. After rule-based classification, linear discriminant analysis (LDA) is used to further reduce the number of false positive (FP) objects. We performed a preliminary study using 1454 CT slices from 34 patients with 63 lung nodules. When only LDA classification was applied to the segmented objects, the sensitivity was 84% (53/63) with 5.48 (7961/1454) FP objects per slice. When rule-based classification was used before LDA, the free response receiver operating characteristic (FROC) curve improved over the entire sensitivity and specificity ranges of interest. In particular, the FP rate decreased to 1.74 (2530/1454) objects per slice at the same sensitivity. Thus, compared to FP reduction with LDA alone, the inclusion of rule-based classification lead to an improvement in detection accuracy for the CAD system. These preliminary results demonstrate the feasibility of our approach to lung nodule detection and FP reduction on CT images.     

Anaphylactic reactions to measles-mumps-rubella vaccine in three children with allergies to hen's egg and cow's milk

Aim: Allergies to hen’s egg and cow’s milk are the most frequent food allergies in infancy and childhood. Current guidelines recommend safe administration of measles–mumps–rubella (MMR) vaccine in egg allergic patients. Methods: We present three cases of anaphylaxis that we encountered after MMR vaccination in children sensitized to hen’s egg and cow’s milk. Results: Even though MMR vaccine is generally known to be safe in children with egg allergy, there may still be isolated cases of anaphylaxis. Conclusion: Therefore, we recommend that all children not only those who were sensitized to foods should receive the MMR vaccination in a setting that is equipped to deal with anaphylactic reactions. As stated by WHO in immunization safety surveillance, ‘Each vaccinator must have an emergency kit with adrenaline, and be familiar with its dosage and administration’.     

Food protein–induced allergic proctocolitis may have distinct phenotypes

BackgroundFood protein–induced allergic proctocolitis (FPIAP) is a non–immunoglobulin E (IgE)-mediated food allergy, which presents with bloody mucoid stool in infants. Although IgE-mediated allergy and sensitizations to offending foods have been described in other non–IgE-mediated food allergies, it has not been investigated in FPIAP.ObjectiveTo investigate IgE-mediated allergy and sensitization to offending foods in FPIAP.MethodsPatients (n = 204) were retrospectively recruited and grouped as FPIAP (n = 180; FPIAP with or without the symptoms of IgE-mediated food hypersensitivity to offending and nonoffending foods at initial consultation), FPIAP-IgE sensitization to offending foods (n = 17), and FPIAP-transition to IgE-mediated allergy to offending foods (n = 7). The study was performed in accordance with the protocol approved by the local ethical committee of the Hacettepe University.ResultsThe median age of onset of symptoms and the development of tolerance was 2 months (interquartile range [IQR], 1.0-3.0) and 12 months (IQR, 10.0-14.0), respectively, and of the patients with skin prick test or serum specific IgE tests (n = 196), 38 (19.4%) had evidence of IgE sensitization to offending foods at the initial consultation or during follow-up; 17 (8.6%) had IgE sensitization, 7 (3.6%) indicated a transition to IgE-mediated allergy to FPIAP-induced foods. The median age of tolerance development of the FPIAP-transition group (19 months, IQR, 18.0-29.0) was significantly later than that of the FPIAP group (11 months, IQR, 10.0-14.0; P < .001) and the FPIAP-IgE sensitization group (11.0 months, IQR, 9.5-12.0; P < .001). Tolerance was observed within the study period in almost all the patients.ConclusionChildren with FPIAP may have sensitization or develop IgE-mediated allergy over time to offending foods. In addition, IgE sensitization in FPIAP does not have an unfavorable effect on tolerance development; however, the transition to an IgE-mediated phenotype may delay tolerance for a brief time.     

von Willebrand factor proteolytic processing and multimerization precede the formation of Weibel-Palade bodies

We investigated the intracellular site of pro-von Willebrand factor (pro-vWF) cleavage and multimerization, as well as the fate of the propolypeptide (von Willebrand antigen II) after cleavage. Analysis of subcellular fractions of endothelial cells metabolically labeled with sulfate showed that both cleavage and covalent multimerization occur after sulfation and precede the formation of Weibel-Palade bodies. Because sulfation is a processing step localized to the trans-Golgi network (TGN), our results indicate that multimerization and prosequence cleavage also occur in this organelle. After cleavage, the propolypeptide remains noncovalently associated with the mature vWF subunit. This association is promoted by a high calcium concentration and an acidic pH (conditions thought to prevail in the TGN) and explains the 1:1 stoichiometry of the propolypeptide and mature vWF found in Weibel-Palade bodies. The propolypeptide remains an integral part of the large multimeric vWF aggregates in the Weibel-Palade body until secretion. When secretion occurs under slightly acidic conditions, such as may be found in poorly perfused wounds, the propolypeptide remains associated with the endothelial surface-bound vWF, and may thus participate in the wound healing process.     

Patch testing is an effective method for the diagnosis of carbamazepine‐induced drug reaction,eosinophilia and systemic symptoms (DRESS) syndrome in an 8‐year‐old girl

Drug reaction, eosinophilia and systemic symptoms (DRESS) is an acute and life‐threatening disease, characterised by fever, rash and systemic symptoms, including lymphadenopathy, abnormal liver function, interstitial nephritis, pulmonary and cardiac infiltrates and haematological abnormalities with eosinophilia and atypical lymphocytes. The drugs mostly associated with DRESS are anticonvulsants, allopurinol, minocycline and sulfonamides. This syndrome is rarely seen in childhood even though a large number of children have anticonvulsant treatment. An 8‐year‐old girl was admitted with fever, lymphadenopathy and skin eruptions on her trunk. Her medical history was notable for epilepsy and carbamazepine treatment had been started 5 weeks previously. Laboratory studies showed a white cell count of 6200/µL (normal, 4100–11 200/µL) with 22% eosinophils and a γ‐glutamyl transpeptidase level of 296 U/L (normal, 0–23 U/L). Laboratory tests for infections and collagen diseases were in the normal range. Persistence of fever and maculopapular eruption with generalised desquamation and the appearance of cheilitis and facial angioedema suggested a hypersensitivity reaction to carbamazepine. The carbamazepine was replaced with levetiracetam. All clinical symptoms improved within a week with corticosteroids and antihistamine treatment. Six weeks after complete recovery an epicutaneous patch test with carbamazepine was performed and a carbamazepine‐induced positive skin reaction was observed at 48‐h. Carbamazepine‐induced DRESS syndrome is a rare entity in children. An epicutaneous patch test is a useful tool for identifying the inducing agent for the DRESS syndrome and for identifying a safe anticonvulsant drug.     

Quantitative evaluation improves specificity of myocardial perfusion SPECT in the assessment of functionally significant intermediate coronary artery stenoses: a comparative study with fractional flow reserve measurements

Objective

Myocardial perfusion SPECT (MPS) is a noninvasive method commonly used for assessment of the hemodynamic significance of intermediate coronary stenoses. Fractional flow reserve (FFR) measurement is a well-validated invasive method used for the evaluation of intermediate stenoses. We aimed to determine the association between MPS and FFR findings in intermediate degree stenoses and evaluate the added value of quantification in MPS.

Methods

Fifty-eight patients who underwent intracoronary pressure measurement in the catheterization laboratory to assess the physiological significance of intermediate (40–70 %) left anterior descending (LAD) artery lesions, and who also underwent stress myocardial perfusion SPECT either for the assessment of an intermediate stenosis or for suspected coronary artery disease were analyzed retrospectively in the study. Quantitative analysis was performed using the 4DMSPECT program, with visual assessment performed by two experienced nuclear medicine physicians blinded to the angiographic findings. Summed stress scores (SSS) and summed difference scores (SDS) in the LAD artery territory according to the 20 segment model were calculated. A summed stress score of ≥3 and an SDS of ≥2 were assumed as pathologic, indicating significance of the lesion; a cutoff value of 0.75 was used to define abnormal FFR. Both visual and quantitative assessment results were compared with FFR using Chi-square (χ²) test.

Results

The mean time interval between two studies was 13 ± 11 days. FFR was normal in 45 and abnormal in 13 patients. Considering the FFR results as the gold standard method for assessing the significance of the lesion, the sensitivity and specificity of quantitative analysis determining the abnormal flow reserve were 85 and 84 %, respectively, while visual analysis had a sensitivity of 77 % and a specificity of 51 %. There was a good agreement between the observers (κ = 0.856). Summed stress and difference scores demonstrated moderate inverse correlations with FFR values (r = ?0.542, p < 0.001 and r = ?0.506, p < 0.001, respectively).

Conclusions

Quantitative analysis of the myocardial perfusion SPECT increases the specificity in evaluating the significance of intermediate degree coronary lesions.     

An unexpected parasitic cause of hypereosinophilia: fascioliasis

A six-year-old boy from Eastern Anatolia was admitted to our outpatient clinic with abdominal pain and hyperleukocytosis. His leukocyte count was 50 x 10(9)/L with an 80% eosinophilia. Serological investigation was positive at a titration of 1/2560 for Fasciola hepatica. Hepatomegaly with linear hypoechogenic strains, which is typical for F. hepatica, was seen on abdominal ultrasonography. He was successfully treated with triclabendazole, 10 mg/kg/day. He is now under follow-up without any complaints. Hypereosinophilia mimicking leukemia is not an expected finding. To our best knowledge, high leukocyte count with F. hepatica in a child has not been reported in the literature until now.