Snowboarding injuries: a review of the literature and an analysis of the potential use of portable ultrasound for mountainside diagnostics.

Snowboarding has become a popular recreational and professional sport. Participants suffer a variety of injuries, especially of the extremities, that require medical evaluation. This article reviews the reported injuries to both leisure and elite athletes. To many, an injured extremity requires travel to a medical facility for accurate evaluation. Musculoskeletal ultrasound is an accurate and portable technology that can be used for real time, mountainside diagnoses of these injuries.

[Glare and contrast with diffraction intraocular lenses]. / Blendung und Kontrast bei Diffraktionsintraokularlinsen.

The quality of vision in patients with a diffractive multifocal intraocular lens was tested and compared to monofocal IOLs and to eyes with a beginning cataract. An automatic computer-assisted visual acuity and contrast-sensitivity test was used. Diffractive IOLs showed reduced contrast sensitivity in both dark contrast testing and bright contrast testing. The differences from monofocal IOLs were not statistically significant. Glare sensitivity was of the same degree in both IOL groups. In additional, visual acuity under reduced contrast conditions was measured at the Ocutrast with and without glare. There was no significant difference between IOL groups. The results obtained showed that contrast sensitivity with diffractive IOLs is not as good as with monofocal IOLs. In this study no significant differences were found.

[Absorption of adrenaline after local administration to the eye]. / Die Resorption von Adrenalin nach lokaler Applikation am Auge.

Twenty patients undergoing surgery for correction of strabismus under general anesthesia were randomly selected to receive conjunctival application of 100 microliters (20 micrograms) adrenaline in both eyes or in neither (controls). A further 20 patients undergoing cataract surgery with local anesthesia were randomly selected to receive 1 ml adrenaline 1:10 000 (100 micrograms) or 1 ml balanced salt solution (controls) in the anterior chamber. Adrenaline in plasma was measured in six time points within 15 min (correction of strabismus) or at seven within 30 min (cataract surgery). Plasma levels of adrenaline, mean arterial pressure, and heart rate were comparable in treatment groups and controls. No severe arrhythmias were observed. Neither conjunctival application of 20 micrograms adrenaline or instillation of 100 micrograms adrenaline into the anterior chamber increases adrenaline levels in plasma, and there is no reason to suspect cardiovascular interactions.

[Ocutrast--a new procedure for measuring mesopic visual acuity and glare sensitivity]. / Ocutrast--ein neues Verfahren zur Messung der Dämmerungssehschärfe und Blendempfindlichkeit.

Measurements of glare sensitivity and mesopic visual acuity are becoming increasingly important for clinical use. They can help to trace indications for cataract operation at an early stage or for YAG laser capsulotomy in cases of mild capsular fibrosis. Up to now, there are no standardized methods for monocular and binocular measurements. A new instrument named Ocutrast has been developed. A study of 100 healthy subjects aged up to 60 years was carried out. Under a field luminance of 1.0 cd/m2 and a contrast of 1:23, visual acuity was measured without and with glare. Standardized conditions were guaranteed. The mean values were lower at higher age, but were not reduced under glare. Additionally two groups of patients (n = 50) were examined. In cataract eyes and in pseudophakic eyes a one line reduction of mesopic visual acuity under glare was found. The conclusion is: a two line reduction of mesopic visual acuity between measurements without and with glare can be regarded to be out of range. Under clinical aspects, this method can contribute to the indication to cataract operation or to YAG laser capsulotomy in pseudophakic eyes.

[Diffractive multifocal intraocular lenses. A prospective clinical study]. / Diffraktive multifokale Intraokularlinsen. Eine prospektive klinische Studie.

Forty-three patients were examined three months after implantation of a multifocal or bifocal intraocular lens following cataract extraction. With far vision correction, simultaneous bifocal function with far acuity better than 0.5 and near acuity better than Nieden 3 was achieved in 95.4% of these cases. Glare sensitivity was tested with the BAT and mesopic visual acuity was examined with the Ocutrast. No statistical differences were found between these patients and a control group with monofocal IOLs.

[Special intra-ocular lenses]. / Spezielle Intraokularlinsen.

Intraocular lens (IOL) implantation is the method established worldwide for visual rehabilitation following cataract surgery. IOL's with particular characteristics and/or for special purposes are available for clinical or experimental use. Bifocal and multifocal IOLs have two or more foci for simultaneous far and near vision. The first clinical results are promising. The theoretically expected disadvantages, i.e., reduced contrast sensitivity or reduced visual acuity under reduced contrast conditions, have not yet been found in clinical studies. In cases of age-related macular degeneration, IOLs with a high negative diopter power in the center can be implanted as part of a Galilei telescope. By using high-plus power spectacles, a 2.5x to 4x magnification and a wide field of view can be achieved. Clinical investigation has started recently. Intraocular lenses for the correction of high-grade myopia are being tested by some surgeons. These lenses are made to be implanted in phakic eyes with a clear crystalline lens. Angle-supported and iris-fixated types are under investigation. Longterm results will show the clinical efficacy and safety. Other special intraocular lenses are iris-color lenses and a polymethymethacrylate (PMMA) iris diaphragm.

[Absorption and fluorescence spectrometry measurement of intraocular lenses]. / Absorptions- und fluoreszenzspektrometrische Messungen an Intraokularlinsen.

Light absorption and fluorescence measurements can be used to detect accumulations of small molecules in intraocular lenses (IOLs). It was shown that HEMA IOLs can store and to some extent release a variety of drugs and fluorescein. PMMA and silicone IOLs, however, do not have this characteristic. UV-blocking IOLs absorb UV light completely. The absorption limit varies between 390 and 410 nm, depending on the make. Neither absorption nor fluorescence response were affected by exposure to UV light or heat.

[Measuring cyclodeviations]. / Die Messung von Zyklodeviationen.

This paper presents the results of a physiological study in which four methods used to measure cyclophoria were compared. A total of 50 persons without strabismus participated in a series of experiments. Monocular and binocular measurements were made in primary position. It was found that different methods have different means and ranges. Thus, when conducting clinical follow-up examinations, the same method should be used as before. The double-scale Maddox cylinder was found to be a simple and reliable screening method. The mean is close to 0 degrees and the physiologic range varies from 2 degrees incyclophoria to 2 degrees excyclophoria.

[New materials for intraocular lenses]. / Neue Materialien bei Intraokularlinsen.

The first intraocular lens implanted in a human eye 39 years then lenses ago, was made of polymethylmethacrylate (PMMA). Today this material is considered to be the standard, so every new type of material is compared to PMMA and must fulfil the requirements demanded of an intraocular implant today. Therefore, every attempt is made to use PMMA as the main structure while eliminating the disadvantageous characteristics even though they are minimal. Thus, the hydrophobic surface can be made more biocompatible by heparin-surface modification. In recent years, hydroxyethylmethacrylate (HEMA) and silicone have achieved a certain level of clinical importance. Another of the new materials is polycarbonate, which is still in the preclinical phase.

[Refraction of the dog eye]. / Refraktion des Hundeauges.

The refraction of 50 eyes of nonsedated dogs was measured by retinoscopy. The slightly hyperopic to middle-grade myopic refraction found in earlier studies was seen in individual cases; however the mean value of 0.5 D is close to emmetropy. The differences in the results of measurements made under non-influenced accommodation and cycloplegia were not significant. Keratometry with the Javal ophthalmometer showed a mean cornea radius of 8.77 mm. A average axial length of 20.9 mm was determined by sonography. In some instances the parameters examined varied considerably.