Digital adaptation of teaching disaster and deployment medicine under COVID-19 conditions: a comparative evaluation over 5 years.

BACKGROUND: The COVID-19 pandemic has not only brought many aspects of disaster medicine into everyday awareness but also led to a massive change in medical teaching due to the necessity of contact restrictions. This study aimed to evaluate student acceptance of a curricular elective module on disaster and deployment medicine over a 5-year period and to present content adjustments due to COVID-19 restrictions. METHODS: Since 2016, 8 semesters of the curricular elective module took place in face-to-face teaching (pre-COVID-19 group). From the summer semester of 2020 to the summer semester of 2021, 3 semesters took place as online and hybrid courses (mid-COVID-19 group). Student attitudes and knowledge gains were measured using pretests, posttests, and final evaluations. These data were statistically compared across years, and new forms of teaching under COVID-19 conditions were examined in more detail. RESULTS: A total of 189 students participated in the module from the summer semester of 2016 through the summer semester of 2021 (pre-COVID-19: n = 138; mid-COVID-19: n = 51). There was a high level of satisfaction with the module across all semesters, with no significant differences between the groups. There was also no significant difference between the two cohorts in terms of knowledge gain, which was always significant (p < 0.05). COVID-19 adaptations included online seminars using Microsoft Teams or Zoom, the interactive live-streaming of practical training components, and digital simulation games. CONCLUSION: The high level of satisfaction and knowledge gained during the module did not change even under a digital redesign of the content offered. The curricular elective module was consistently evaluated positively by the students, and the adaptation to online teaching was well accepted. Experiences with digital forms of teaching should also be used after the COVID-19 pandemic to create digitally supported blended learning concepts in the field of deployment and disaster medicine and thus further promote the expansion of teaching in this important medical field.

[Periprosthetic fractures of the acetabulum: osteosynthesis]. / Periprothetische Frakturen des Acetabulums: Osteosynthese.

In most cases periprosthetic fractures of the acetabulum are complex injuries and are extremely challenging for the treating medical team. Over the years the frequency of this overall rare entity has increased due to demographic changes. In recent years several treatment algorithms were published and provided the possibility of developing standardized treatment concepts. The classification of the fractures and a dedicated preoperative strategy are highly important for the quality of patient-centered care. In the literature the frequency of intraoperative fractures was initially given as 0.4%; however, several studies have been published in which a far higher rate of intraoperative fractures was detected by computed tomography (CT), often referred to as so-called occult fractures. The causes are multifactorial and there is significant association with whether cement-free press-fit acetabular cups were used or cemented forms. In approximately 75% of the cases a low energy impact was the cause of the fracture. In these patients systemic processes, such as osteoporotic alterations of the bony substance or the possible presence of low-grade infections should be considered. This article gives an overview of the diagnostics, planning, challenges and osteosynthetic treatment options for periprosthetic fractures of the acetabulum.

Acetabular Fractures in an Advanced Age - Current Knowledge and Treatment Options.

The demographic change in industrial countries leads to an increasing population that sustains an acetabular fracture in an advanced age. Some authors predicted elderly individuals to be the most rapidly growing subgroup of patients currently sustaining acetabular fractures. Gold standard of treatment of acetabular fractures remains the open reduction and internal fixation. Relevant factors impeding surgical treatment include the significantly decreased bone stock and the incapability of the patients to partially weight bear following surgery. Therefore, special considerations should be performed when dealing with this patient group as surgical treatment is associated with several risks and often accompanied by poor outcomes. This review aims to summarize the current body of knowledge and to give a recommendation concerning a surgical treatment cascade.

[Lithium and its protective effect in Alzheimer's disease]. / Het beschermende effect van lithium bij de ziekte van Alzheimer.

BACKGROUND: Lithium is associated with adverse effects on cognitive functioning. However, there are published trials that have investigated the protective effects of lithium in cognitive decline.
AIM: To review studies that investigate the potentially protective effects of lithium on cognitive disorders.
METHOD: We studied English-language and Dutch reports on controlled, clinical trials published up to October 2016.
RESULTS: We found four relevant articles. Two studies indicated that cognitive functioning remained more stable when patients were given lithium than when they were given a placebo. One study, however, could not detect any difference between the effects of lithium and the effects of placebos. The fourth study, which examined patients' ability to tolerate lithium, could not find any difference in the cognitive functioning of patients.
CONCLUSION: The reported results indicate that the cognitive functioning of patients with pre-stage Alzheimer's disease remains more stable after patients have taken lithium than after they have taken a placebo.

Fixation of acetabular fractures via the ilioinguinal versus pararectus approach: a direct comparison.

This study compared the quality of reduction and complication rate when using a standard ilioinguinal approach and the new pararectus approach when treating acetabular fractures surgically. All acetabular fractures that underwent fixation using either approach between February 2005 and September 2014 were retrospectively reviewed and the demographics of the patients, the surgical details and complications were recorded. A total of 100 patients (69 men, 31 women; mean age 57 years, 18 to 93) who were consecutively treated were included for analysis. The quality of reduction was assessed using standardised measurement of the gaps and steps in the articular surface on pre- and post-operative CT-scans. There were no significant differences in the demographics of the patients, the surgical details or the complications between the two approaches. A significantly better reduction of the gap, however, was achieved with the pararectus approach (axial: p = 0.025, coronal: p = 0.013, sagittal: p = 0.001). These data suggest that the pararectus approach is at least equal to, or in the case of reduction of the articular gap, superior to the ilioinguinal approach. This approach allows direct buttressing of the dome of the acetabulum and the quadrilateral plate, which is particularly favourable in geriatric fracture patterns.

Insulin-like growth factor type-1 receptor down-regulation associated with dwarfism in Holstein calves.

Perturbations in endocrine functions can impact normal growth. Endocrine traits were studied in three dwarf calves exhibiting retarded but proportionate growth and four phenotypically normal half-siblings, sired by the same bull, and four unrelated control calves. Plasma 3,5,3'-triiodothyronine and thyroxine concentrations in dwarfs and half-siblings were in the physiological range and responded normally to injected thyroid-releasing hormone. Plasma glucagon concentrations were different (dwarfs, controls>half-siblings; P<0.05). Plasma growth hormone (GH), insulin-like growth factor-1 (IGF-1) and insulin concentrations in the three groups during an 8-h period were similar, but integrated GH concentrations (areas under concentration curves) were different (dwarfs>controls, P<0.02; half-siblings>controls, P=0.08). Responses of GH to xylazine and to a GH-releasing-factor analogue were similar in dwarfs and half-siblings. Relative gene expression of IGF-1, IGF-2, GH receptor (GHR), insulin receptor, IGF-1 type-1 and -2 receptors (IGF-1R, IGF-2R), and IGF binding proteins were measured in liver and anconeus muscle. GHR mRNA levels were different in liver (dwarfs

Pinhole eyewear systems: a special report.

Multiple pinhole discs are being promoted as part of systems claimed capable of correcting refractive error. Attempts to mitigate refractive error utilize training attributable to the systems of Bates, Peppard, and Huxley. The pinhole discs provide an array of 0.9mm apertures separated by 3mm horizontally and vertically. Because of the small aperture size, some of the optical advantages of the pinhole are offset by diffraction effects. The discs can produce multiple images and the visual experience of individuals will be a function of the user's pupil size and refractive error. These are discussed both theoretically and based on the author's observations wearing the spectacles.

Clinical comparison of the TruVision Omni and four progressive addition lenses.

The TruVision Omni is a progressive addition lens (PAL) using a bipolar design and the Dirichlet principle to minimize optical aberrations. The design was evaluated by having each patient elect to keep one lens type after masked paired comparison of the TruVision Omni with one of four other PAL types: VIP, Varilux, New Super NoLine, and Gradal HS. The Omni was chosen most frequently in each case: 16 to 8, 17 to 6, 18 to 6, and 15 to 3, respectively. Thirty-seven percent reported that no adaptation was required with the Omni compared to 20% for the paired PAL. In terms of specific performances, Omni tended to rank highest for intermediate distance functions and freedom from distortion, average for distance functions, and slightly above average for near function. The data support the merit of Omni's design strategy.

The Badal optometer paradox.

Badal's optometer is used to change the vergence of the accommodative stimulus without changing retinal image size. It has been accepted that this can be accomplished by putting the optometer's secondary focal point at either the eye's anterior nodal or anterior focal point. I show that there can be only one solution because the simultaneous truth of both solutions would lead to a paradox. The most precise solution is slightly different for the accommodated and the unaccommodated eye, but the nodal point provides the best general solution. For the accommodating eye there is a residual increase in image size with accommodation due to the anterior displacement of the nodal points. For the unaccommodated eye, the correct reference point is its entrance pupil. Use of the nodal point results in accommodation creating an anomalous, but slight, change in retinal image size.

Solar radiation and the eye: a review of knowledge relevant to eye care.

Solar radiation has been implicated, with a variety of evidence, as a causative agent in photokeratoconjunctivitis, pinguecula and pterygium, nodular band keratopathies, epidermoid carcinoma, cataract, solar retinopathy, and macular degeneration. Much of the support for claims relating to chronic conditions having serious consequences and significant prevalence in the United States rests on investigations using animals and short-time exposures at high intensities. The direct applicability of these studies to humans in natural environments is uncertain, but they have been relied on because one cannot deliberately induce significant trauma in humans. The use of animal data is made difficult by the need to convert animal thresholds to human equivalents, to equate laboratory cycles and magnitudes of exposure to those in the natural environment, and to quantify the impact of avoidance and protective mechanisms. Risk can be assessed adequately only by epidemiological studies, but their potential has been only partially realized because of poorly controlled confounding variables. Epidemiologic evidence suggests that corneal trauma from ultraviolet radiation (UVR) is a risk of prolonged exposure in regions containing much ultraviolet (UV) or in highly reflective environments. The impact of UV-B on cataractogenesis has been investigated inadequately and no evidence exists for retinal trauma arising from routine exposure in even the brightest surroundings. However, there can be no question that enough solar energy reaches the earth to harm the eye if unattenuated. Damage to vision as a result of direct solar viewing demonstrates that unequivocally. The lack of clear evidence of radiation damage occurring other than in regions of high reflectivity and/or low horizons suggests that in normal surroundings there is little or no risk to the eye, although more careful epidemiological investigation is required before all concern can be ruled out completely. The major improvement required is the quantification of individual exposure histories. This step is necessary if we are to make significant progress toward better understanding the practical impact of solar radiation on the eye.

Brock's research in stereopsis.

While Frederick Brock's contributions to vision training are numerous, little of his work dealt specifically with stereopsis, mostly concentrating on its application to diagnosis and therapy of binocular dysfunction. He did demonstrate, qualitatively, how differences in the size or clarity of retinal images affect stereopsis. The theoretical basis of his work, as well as his published and unpublished contributions, are reviewed in the context of the author's personal experience with this singular person.

New technique for repair of posterior left ventricular rupture.

A case is presented of posterior left ventricular rupture occurring from resection of intramyocardial calcification during mitral valve replacement. The laceration was obvious on the operating table with discontinuation of cardiopulmonary bypass, but attempts at simple closure with buttressd sutures were unsuccessful. The ventricular defect was repaired by insertion of a low-porosity Dacron graft. A saphenous vein bypass graft was also placed between the aorta and circumflex coronary artery.

Evaluation of the pneuma-tonometer.

Intraocular pressure in 125 randomly selected patients visiting the eye clinic at the Massachusetts Institute of Technology for routine care was measured with a Goldmann applanation tonometer and a model 30R Pneuma-Tonometer. Pairs of reading were taken with each instrument when possible, and each trace of the Pneuma-Tonometer measurement was subsequently read blind and independently by two observers. The standard deviation of the differences between the two readers' values obtained on 416 traces was 0.44 mm Hg. The standard deviation of the differences between paired Pneuma-Tonometer readings on 186 eyes was 1.75 mm Hg. With data selected for cause the mean Pneuma-Tonometer reading was 0.40 mm Hg higher, the standard deviation of the differences between the instruments was 1.50 mm Hg, and the correlation coefficient was 0.88. Alternatives to the customary use of linear regression methods of assessing calibration are proposed.

A clinical evaluation of the non-contact tonometer.

Paired non-contact tonometer readings were taken on patients at the Boston City Hospital Eye Clinic before and after routine vision care that included Goldmann tonometry. The variability of NCT readings was determined and comparisons made between readings obtained with the NCT and Goldmann instruments. The regression equation relating the pre-Goldmann NCT findings (N1), to the Goldmann (G), was N1 = 1.01G + 1.97; and the equation relating the post-Goldmann NCT findings (N2), to the Goldman was N2 = .94G + 1.70. The N1 mean was 2.06 mm. higher than the mean G, while the N2 mean was .58 mm. higher than the mean G. The correlation coefficients and standard deviation of the differences for the two comparisons were, .88, 3.91, and .93, 3.07, respectively. The Goldmann findings therefore were seen to agree more closely with the NCT findings taken after them. The linear regression and correlation coefficients between the NCT and the Goldmann were generally in good agreement with those of prior studies, although the standard deviations of the differences between findings were larger in this study. This result is not surprising since no attempt was made to train Goldmann operators to criterion or to limit variability induced by differing observer criteria or by the use of only one Goldmann operator. The operators of the Goldmann tonometer had varying degrees of training as residents in ophthalmology. Interestingly, the agreement between pre-Goldmann NCT and post-Goldmann NCT findings was not good. This suggested that the taking of the Goldmann findings themselves may have had a significant effect on the tonometric readings and that the considerable time that frequently took place between the two sets of NCT readings could have affected the value. The standard deviation of the differences between pre- and post-Goldmann readings on the same patient was 3.27 as compared to that for paired readings which was 2.28. The data also showed a much better agreement between the NCT and the rechecked Goldmann findings than between the initial Goldmann findings and the rechecked Goldmann findings, indicating that where discrepancies existed, it was more likely that they were due to the Goldmann instrument.