In vivo confocal microscopy of climatic droplet keratopathy

We describe the corneal microstructural changes in a patient with spheroidal degeneration using in vivo confocal microscopy. Multiple hypo‐ and hyper‐reflective spherical lesions were observed in the anterior corneal stroma and Bowman's layer ranging from 45 to 220 μm in size. The corneal epithelium, posterior stroma and endothelium were otherwise unaffected. In vivo confocal microscopy demonstrates good correlation with excised histological samples in climatic droplet keratopathy. It provides a non‐invasive technique to examine the living cornea for degenerative disease and acts as a bridge between clinical and laboratory observations.     

Differential diagnosis of corneal oedema assisted by in vivo confocal microscopy

The purpose of this study was to demonstrate microstructural differences between clinically similar, but aetiologically different, cases of corneal oedema in four subjects. In vivo confocal microscopy highlighted oedema of the basal epithelium, prominent nerve–keratocyte interactions, and typical ‘epithelialization’ of the endothelium in a case of iridocorneal endothelial syndrome; however, a similar microstructural appearance was observed in a case of presumed herpetic disciform keratitis. The latter diagnosis was subsequently revised on this basis. Confocal examination of Fuchs’ endothelial dystrophy demonstrated oedema of the basal epithelium, prominent wing cells, anterior stromal alterations, fibrosis of Descemet’s membrane and a typical ‘strawberry’ appearance of the endothelium. In contrast, in vivo microstructural examination of bilateral keratoconus with hydrops confirmed oedema mainly involving the epithelium and anterior stroma. In vivo confocal microscopy allows the clinician to observe the living cornea at a microstructural level and to better diagnose and differentiate borderline or unusual cases of corneal oedema.     

Family history of myocardial infarction is an independent risk factor for venous thromboembolism: the Tromsø study

Summary. Background: Recent studies indicate that arterial cardiovascular diseases and venous thromboembolism (VTE) share common risk factors. A family history of myocardial infarction (MI) is a strong and independent risk factor for future MI. Objectives: The purpose of the present study was to determine the impact of cardiovascular risk factors, including family history of MI, on the incidence of VTE in a prospective, population‐based study. Patients and methods: Traditional cardiovascular risk factors and family history of MI were registered in 21 330 subjects, aged 25–96 years, enrolled in the Tromsø study in 1994–95. First‐lifetime VTE events during follow‐up were registered up to 1 September 2007. Results: There were 327 VTE events (1.40 per 1000 person‐years), 138 (42%) unprovoked, during a mean of 10.9 years of follow‐up. In age‐ and gender‐adjusted analysis, age [hazard ratio (HR) per decade, 1.97; 95% confidence interval (CI), 1.82–2.12], gender (men vs. women; HR, 1.25; 95% CI, 1.01–1.55), body mass index (BMI; HR per 3 kg m^?2, 1.21; 95% CI, 1.13–1.31), and family history of MI (HR, 1.31; 95% CI, 1.04–1.65) were significantly associated with VTE. Family history of MI remained a significant risk factor for total VTE (HR, 1.27; 95% CI, 1.01–1.60) and unprovoked VTE (HR, 1.46; 95% CI, 1.03–2.07) in multivariable analysis. Blood pressure, total cholesterol, HDL‐cholesterol, triglycerides, and smoking were not independently associated with total VTE. Conclusions: Family history of MI is a risk factor for both MI and VTE, and provides further evidence of a link between venous and arterial thrombosis.     

The friction of explanted hip prostheses

Charnley prostheses, retrieved at revision surgery, were studied to assess the effects of friction on the total hip replacement procedure. Frictional resistance was measured using the Durham hip function simulator under both dry and lubricated conditions. The friction factor values (f) for the explanted prostheses were found to have a non- Gaussian distribution with medians of 0.13 [inter-quartile range (IQR) 0.10-0.16] and 0.06 (IQR 0.005-0.08) for dry and lubricated (n = 0.01 Pa s) regimes, respectively. New Charnley prostheses had values of f equal to 0.11 +/- 0.025 and 0.04 +/- 0.01 under the same conditions, and showed no large deviation from a Gaussian distribution. There was found to be a statistically significant difference in the medians of the friction factors for new and retrieved prostheses in the lubricated regime. Ingression of cement into the worn region of the cup was found to increase the friction factor significantly under dry conditions. There was no evidence of an increase in the friction factor or torque for those joints that had a loose socket with respect to those that were fixed at revision. A decrease in the frictional torque against number of cycles undergone by the joint in vivo may indicate that a fatigue-type process may have a role in the loosening of the socket. However, this relationship was found not to be significant for friction measured under lubricated conditions and it seems unlikely that the frictional torque generated in this type of prosthesis will contribute significantly to the long-term loosening of the socket.      

Daily variation in gastric emptying when using the double sampling technique.

The purpose of this study was to establish the intra-individual variation in the rate of gastric emptying (GE) by using the double sampling technique of George. Eight healthy male volunteers, all familiar with gastric intubation and testing, participated in four GE tests, using an isotonic fluid as a test meal. Conditions were kept constant during all four tests, and each test was separated by at least 48 h. The within-subjects coefficient of variation proved to be 29%. The findings demonstrate that, given standard conditions, GE is reproducible from day to day.     

Studies in gastric emptying and fluid balance during exericse

The problems of rehydration during exercise are addressed. Dehydration will reduce circulatory capacity, cooling and exercise efficiency and hence reduce athletic performance. However, athletes attempting to supplement fluid intake during performance commonly complain of gastrointestinal (GI) discomfort.
Experiments are described investigating the relationship between GI function and fluid supplementation. The authors conclude that fluids should be taken early in the exercise period, before dehydration sets in.