No evidence for left ventricular diastolic dysfunction in asymptomatic normotensive type 2 diabetic patients: a case-control study with new echocardiographic techniques

OBJECTIVE: We sought to determine whether abnormalities of left ventricular structure and function could be detected in asymptomatic type 2 diabetic patients free of cardiovascular complications. RESEARCH DESIGN AND METHODS: We compared 48 subjects with type 2 diabetes (34 men, 50+/-6 years) without hypertension, coronary artery disease and microangiopathic complications with 30 age-matched healthy controls. Left ventricular diastolic function was assessed by conventional Doppler echocardiography and new echocardiographic techniques (tissue Doppler imaging, color M-mode propagation velocity). A pseudonormal (PN) pattern of left ventricular filling was screened by several methods including Valsalva maneuver. RESULTS: Systolic function was normal in all patients. There was no significant difference in conventional and new echocardiographic Doppler indices of diastolic function between patients and control subjects. A PN diastolic function frequently suggested by the Valsalva maneuver (20 patients) was excluded using the new parameters. CONCLUSIONS: Diastolic dysfunction is not as frequent as previously described in selected patients with type 2 diabetes free of microangiopathic complications. New Doppler echocardiographic methods provide, in contrast with the Valsalva maneuver, a reliable estimate of diastolic function and should be incorporated in the non-invasive screening for diabetic cardiomyopathy.     

Clinicopathological differences between hepatitis B viral genotype B- and C-related resectable hepatocellular carcinoma

Clinical and pathogenic differences exist between hepatitis B viral (HBV) genotypes B and C, and genotype C has a higher risk of hepatocellular carcinoma (HCC) development than genotype B. The aim of this study was to investigate whether HBV genotypes B and C influence the clinicopathological features of patients with resectable HCC. Stored serum samples from 193 patients with resectable HBV-related HCC were tested for HBV genotypes by a molecular method. Of 193 patients undergoing resection of HCC, 107 (55%) and 86 (45%) were infected with genotypes B and C, respectively. Compared with genotype C patients, genotype B patients were less likely to be associated with liver cirrhosis (33%vs 51%, P = 0.01). Pathologically, genotype B patients had a higher rate of solitary tumour (94%vs 86%, P = 0.048) and more satellite nodules (22%vs 12%, P = 0.05) than genotype C patients. Our results indicate that genotype B-related HCC is less associated with liver cirrhosis and has a higher frequency of solitary tumour as well as more satellite nodules than genotype C-related HCC. These characteristics may contribute to the recurrence patterns and prognosis of HBV-related HCC in patients with genotype B or C infection.     

Quantification of tooth wear: Conventional vs new method using toolmakers microscope and a three-dimensional measuring technique

Objectives

This study aimed to evaluate the reliability of a new CAD-CAM Laser scanning machine in detection of incisal tooth wear through a 6-month period and to compare the accuracy of using this new machine against measuring tooth wear using tool maker microscope and conventional tooth wear index.

Methods

Twenty participants (11 males and 9 females, mean age = 22.7 years, SD = 2.0) were assessed for incisal tooth wear of lower anterior teeth using Smith and Knight clinical tooth wear index (TWI) on two occasions, the study baseline and 6 months later. Stone dies for each tooth were prepared and scanned using the CAD-CAM Laser Cercon System (Cercon Smart Ceramics, DeguDent, Germany). Scanned images were printed and examined under a toolmaker microscope (Stedall-Dowding Machine Tool Company, Optique et Mecanique de Precision, Marcel Aubert SA, Switzerland) to quantify tooth wear and then the dies were directly assessed under the microscope to measure tooth wear. The Wilcoxon Signed Ranks Test was used to analyse the data.

Results

TWI scores for incisal edges were 0, 1, and 2 and were similar at both occasions. Scores 3 and 4 were not detected. Wear values measured by directly assessing the dies under the tool maker microscope (range = 517–656 μm, mean = 582 μm, and SD = 50) were significantly more than those measured from the Cercon digital machine images (range = 132–193 μm, mean  = 165 μm, and SD = 27) and both showed significant differences between the two occasions.

Conclusions

Measuring images obtained with Cercon digital machine under tool maker microscope allowed detection of wear progression over the 6-month period. However, measuring the dies of worn dentition directly under the tool maker microscope enabled detection of wear progression more accurately. Conventional method was the least sensitive for tooth wear quantification and was unable to identify wear progression in most cases.     

Thermographic assessment of root canal obturation using thermomechanical compaction

The temperature changes on the root surface of 30 extracted human premolar teeth during thermomechanical root canal obturation with gutta-percha were determined using an infrared thermal imaging camera. Three handpiece rotational speeds of 8, 12 and 16 × 10³ r.p.m. were used, in conjunction with a Gutta Condensor. On completion of the procedure, the quality of tooth canal obturation was examined radiographically. Under the conditions of this experiment, surface root temperature rises of >97°C were recorded during all three speed settings. The radiographic quality of obturation between the groups appeared not to be significantly different. The clinical relevance of these findings is uncertain, but the temperatures reported are of a magnitude to be of biological importance.     

Geographical variation in the prevalence of positive skin tests to environmental aeroallergens in the European Community Respiratory Health Survey I

BACKGROUND: Many studies have reported the prevalence of sensitization using skin prick tests. However, comparisons between studies and between regions are difficult because the number and the type of allergens tested vary widely. Using the European Community Health Respiratory Survey I data, the geographical variation of sensitization to environmental allergen as measured by skin tests was established. METHODS: Adults aged 20-44 years, living in 35 centres in 15 developed countries, underwent skin tests for allergy to nine common aeroallergens: Dermatophagoides pteronyssinus, timothy grass, cat, Cladosporium herbarium, Alternaria alternata, birch, Olea europea, common ragweed and Parietaria judaica. The age-sex standardized prevalence of sensitization was determined and centres with high (95% confidence interval above and excluding study median) and low prevalence (95% confidence interval below and excluding study median) of sensitization to each allergen and to any of the nine allergens were identified. RESULTS: There was substantial geographical variation in the prevalence of sensitization to each of the nine allergens tested and in the prevalence of sensitization to any allergen (lowest 17.1%, median 36.8% and highest 54.8%). Sensitization to D. pteronyssinus, grass pollen and cat were usually the most prevalent (median between centre 21.7%, 16.9% and 8.8%, respectively). Timothy grass sensitization was higher than that for any other pollen species. CONCLUSIONS: As expected, geographical variations of sensitization to environmental allergen were observed across centres. These findings were compatible for those observed with serum-specific IgE. Skin tests can be used to assess the geographical distribution of allergens in a multicentric epidemiological survey.     

Dosimetric advantages of generalised equivalent uniform dose-based optimisation on dose–volume objectives in intensity-modulated radiotherapy planning for bilateral breast cancer

Objective

We compared and evaluated the differences between two models for treating bilateral breast cancer (BBC): (i) dose–volume-based intensity-modulated radiation treatment (DV plan), and (ii) dose–volume-based intensity-modulated radiotherapy with generalised equivalent uniform dose-based optimisation (DV-gEUD plan).

Methods

The quality and performance of the DV plan and DV-gEUD plan using the Pinnacle³® system (Philips, Fitchburg, WI) were evaluated and compared in 10 patients with stage T2–T4 BBC. The plans were delivered on a Varian 21EX linear accelerator (Varian Medical Systems, Milpitas, CA) equipped with a Millennium 120 leaf multileaf collimator (Varian Medical Systems). The parameters analysed included the conformity index, homogeneity index, tumour control probability of the planning target volume (PTV), the volumes V_{20 Gy} and V_{30 Gy} of the organs at risk (OAR, including the heart and lungs), mean dose and the normal tissue complication probability.

Results

Both plans met the requirements for the coverage of PTV with similar conformity and homogeneity indices. However, the DV-gEUD plan had the advantage of dose sparing for OAR: the mean doses of the heart and lungs, lung V_{20 Gy}, and heart V_{30 Gy} in the DV-gEUD plan were lower than those in the DV plan (p<0.05).

Conclusions

A better result can be obtained by starting with a DV-generated plan and then improving it by adding gEUD-based improvements to reduce the number of iterations and to improve the optimum dose distribution.

Advances to knowledge

The DV-gEUD plan provided superior dosimetric results for treating BBC in terms of PTV coverage and OAR sparing than the DV plan, without sacrificing the homogeneity of dose distribution in the PTV.Breast cancer is the most common cancer and the leading cause of cancer deaths in females worldwide, with about 500 000 fatalities each year. In the USA and Europe, breast cancer constitutes, on average, one in four cancer cases among females [1,2]. Breast cancer among females in Asian countries mostly occurs between the ages of 40 and 50 years; however, in females in Western countries, it mostly occurs between the ages of 50 and 60 years [2,3].Bilateral breast cancer (BBC) is very rare, accounting for only 1–3% of all breast cancer cases [4-6]. Generally, no treatment guidelines exist for BBC. The treatment of BBC relies on surgery, chemotherapy and radiation therapy; additionally, BBC has previously demonstrated a poor prognosis. Current evidence indicates that the survival rate of patients with BBC is similar to that of patients with unilateral breast cancer [7,8]. The difficulty in treatment planning for BBC varies greatly, case by case, and is thus a great challenge for radiotherapy. Important issues have been raised concerning how to reduce the dose of radiation to normal tissues, how to maintain a certain tumour control probability (TCP) and how to improve the quality of life for patients with BBC.Most intensity-modulated radiotherapy (IMRT) planning systems apply dose–volume (DV)-based objective functions for dose optimisation, and an acceptable plan can be generated in most cases. For more complex plans, more iterations are required because many parameters need to be finely tuned. A successful improvement tool—the generalised equivalent uniform dose (gEUD)—was developed with fewer parameter settings [9-13] to improve the quality of plans. However, gEUD-based optimisation cannot demonstrate such advantages on the first run; more iterations are required to sculpt the dose distribution [14].To overcome the disadvantages mentioned above, we started with a DV-generated plan, and then improved it by adding gEUD-based improvements. The goal was to reduce the number of iterations and to improve the optimum dose distribution. This method first determined the approximate solutions for most of the treatment targets by DV-based optimisation, and then adjusted the DV histogram (DVH) by gEUD-based optimisation to obtain a superior solution. This study also compared and evaluated the differences between two different methods for the treatment of BBC—(i) a DV plan with DV-based optimisation (DV plan), and (ii) a DV-gEUD plan with mainly DV-based optimisation assisted by gEUD-based optimisation (DV-gEUD plan)—thus providing a quantitative indicator model for reference.     

Comparison of the GlideScope® videolaryngoscope and the Macintosh laryngoscope for double-lumen tube intubation

Intubation with a double‐lumen tube is important for achieving one‐lung ventilation and facilitating thoracic surgery. The GlideScope^® videolaryngoscope (Verathon Inc., Bothell, WA, USA) is designed to assist tracheal intubation for patients with a difficult airway. We wished to compare the GlideScope and direct laryngoscopy for double‐lumen tube intubation. Sixty adult patients requiring a double‐lumen tube for thoracic surgery and predicted uncomplicated laryngoscopy were randomly assigned to a direct Macintosh laryngoscopy group (n = 30) or a GlideScope group (n = 30). The mean (SD) duration of intubation was longer in the Macintosh group (62.5 (29.7) s) than in the GlideScope group (45.6 (10.7) s; p = 0.007). There was no difference in the success of the first attempt at intubation (26/30 (87%) and 30/30 (100%) for Macintosh and GlideScope groups, respectively; p = 0.112). The incidence of sore throat and hoarseness was higher in the Macintosh group (18 (60%) and 14 (47%), respectively) than in the GlideScope group (6 (20%) and 4 (13%), respectively; p = 0.003 and 0.004). We conclude that double‐lumen tube intubation in patients with predicted normal laryngoscopy is easier using the GlideScope videolaryngoscope than the Macintosh laryngoscope.     

Can T1-rho MRI detect acetabular cartilage degeneration in femoroacetabular impingement?: a pilot study

Advanced MRI cartilage imaging such as T(1)-rho (T1ρ) for the diagnosis of early cartilage degradation prior to morpholgic radiological changes may provide prognostic information in the management of joint disease. This study aimed first to determine the normal T1ρ profile of cartilage within the hip, and secondly to identify any differences in T1ρ profile between the normal and symptomatic femoroacetabular impingement (FAI) hip. Ten patients with cam-type FAI (seven male and three female, mean age 35.9 years (28 to 48)) and ten control patients (four male and six female, mean age 30.6 years (22 to 35)) underwent 1.5T T1ρ MRI of a single hip. Mean T1ρ relaxation times for full thickness and each of the three equal cartilage thickness layers were calculated and compared between the groups. The mean T1ρ relaxation times for full cartilage thickness of control and FAI hips were similar (37.17 ms (SD 9.95) and 36.71 ms (SD 6.72), respectively). The control group demonstrated a T1ρ value trend, increasing from deep to superficial cartilage layers, with the middle third having significantly greater T1ρ relaxation values than the deepest third (p = 0.008). The FAI group demonstrated loss of this trend. The deepest third in the FAI group demonstrated greater T1ρ relaxation values than controls (p = 0.028). These results suggest that 1.5T T1ρ MRI can detect acetabular hyaline cartilage changes in patients with FAI.     

Clinical application of computerized continuous-infusion pressure-monitored sialography

The clinical application of computerized continuous-infusion pressure-monitored sialography using an aqueous contrast medium during the investigation of 296 salivary glands is described. A comparison between the pressure changes and the sialographic features revealed a significant (P less than 0.001) correlation between raised filling pressure (greater than 60 mmHg) and the presence of an obstructive lesion (stricture, mucous plug, sialolith). Occasionally a raised filling pressure was observed although the associated sialography films were normal. The sensitivity of the technique was 86.4%. It is concluded that the monitoring of pressure changes occurring during sialography can alert the clinician to the presence of high filling pressure and may also provide additional evidence of obstructive changes within salivary glands.