Factors influencing corneal predescemetic endothelial keratoplasty (PDEK) graft creation: It's all in a bubble.

AIM: To assess the effect of pneumatic (air) and fluidic (transport medium) injection to the type of bubble (I, II or mixed III) and the resultant dissection of corneal endothelial grafts PDEK or DMEK. MATERIALS AND METHODS: All grafts were obtained from Dr Agrawal Hospital's Eye Bank. Air injection was the initial preferred mode of graft harvest. If pneumatic dissection was unsuccessful after 10 tries, fluidic dissection with transport medium was tried. SPSS 23.0 was used to statistically analyse the data. RESULTS: 40 consecutive donor corneas with a mean age of 46.5 and a mean endothelial count of 2980 were analysed. Air dissection lead to the harvest of 27 endothelial grafts and fluid dissection led to the creation of 7 endothelial grafts. Statistically significant difference was found the different bubble types and the type of injection (χ2 chi square=10.02, 0=0.008). CONCLUSION: In young donors pneumatic (air) graft dissection leads to PDEK in a high proportion. This percentage is reduced when transport medium is tried after unsuccessful air injection. Injection of transport medium increases the percentage of grafts harvested but also increases the ratio of Type II and III DMEK grafts created.

Sorting Fermionization from Crystallization in Many-Boson Wavefunctions.

Fermionization is what happens to the state of strongly interacting repulsive bosons interacting with contact interactions in one spatial dimension. Crystallization is what happens for sufficiently strongly interacting repulsive bosons with dipolar interactions in one spatial dimension. Crystallization and fermionization resemble each other: in both cases - due to their repulsion - the bosons try to minimize their spatial overlap. We trace these two hallmark phases of strongly correlated one-dimensional bosonic systems by exploring their ground state properties using the one- and two-body density matrix. We solve the N-body Schrödinger equation accurately and from first principles using the multiconfigurational time-dependent Hartree for bosons (MCTDHB) and for fermions (MCTDHF) methods. Using the one- and two-body density, fermionization can be distinguished from crystallization in position space. For N interacting bosons, a splitting into an N-fold pattern in the one-body and two-body density is a unique feature of both, fermionization and crystallization. We demonstrate that this splitting is incomplete for fermionized bosons and restricted by the confinement potential. This incomplete splitting is a consequence of the convergence of the energy in the limit of infinite repulsion and is in agreement with complementary results that we obtain for fermions using MCTDHF. For crystalline bosons, in contrast, the splitting is complete: the interaction energy is capable of overcoming the confinement potential. Our results suggest that the spreading of the density as a function of the dipolar interaction strength diverges as a power law. We describe how to distinguish fermionization from crystallization experimentally from measurements of the one- and two-body density.

[A New Way to Look Up. Solar Retinopathy Risks and Methods of Prevention Prior to the 2015 Solar Eclipse]. / Risiken und präventive Maßnahmen angesichts der Sonnenfinsternis März 2015.

A solar eclipse is an impressive natural phenomenon that was last experienced in Europe in 2006. Last year, on March 20th 2015, a solar eclipse was visible in much of Europe. Solar retinopathy is a recognised potentially sight threatening condition that has been associated with direct or unprotected sun gazing. Public education has been shown to improve behaviour and attitudes that could influence the development of solar retinopathy during an eclipse. We have performed a study through newspapers prior to the 2015 solar eclipse in different European countries, in order to determine the level of public health awareness and attitudes to protection. Methods: 31 online editions of national newspapers were reviewed from six countries where the eclipse was most visible. Solar retinopathy, potential warnings, safe methods of viewing an eclipse and assessment of use and dangers of modern technologies were assessed. Results: All 25 newspapers examined mentioned the solar eclipse and risk to eyesight. Safe methods for viewing the eclipse were discussed in all newspapers. Eclipse eyeglasses were mentioned in 29 of the 31 newspapers reviewed. Children were identified as a high-risk group but advice for children viewing the eclipse varied between countries. Conclusion: Since the solar eclipse of 2006, there has been an increase in the level of education available in the media. Although the safe methods for viewing an eclipse have not changed in recent years, emerging technologies, such as camera phones and the "selfie" trend, have potentially increased the risk of eclipse-associated retinopathy.

Tracking camera control in endoscopic dacryocystorhinostomy surgery.

OBJECTIVES: Poor camera control during endoscopic dacryocystorhinostomy (EnDCR) surgery can cause inadequate visualisation of the anatomy and suboptimal surgical outcomes. This study investigates the feasibility of using computer vision tracking in EnDCR surgery as a potential formative feedback tool for the quality of endoscope control. DESIGN: A prospective cohort analysis was undertaken comparing junior versus senior surgeons performing routine EnDCR surgery. Computer vision tracking was applied to endoscopic video footage of the surgery: Total number of movements, camera path length in pixels and surgical time were determined for each procedure. A Mann-Whitney U-test was used to test for a significant difference between juniors and seniors (P < 0.05). SETTING: Operating theatre. PARTICIPANTS: Ten junior surgeons (<20 completed procedures) and 10 senior surgeons (>100 completed procedures). MAIN OUTCOME MEASURES: Total number of movements of the endoscope per procedure. Path length of the endoscope per procedure. RESULTS: Twenty videos, 10 from junior surgeons and 10 from senior surgeons were analysed. Feasibility of our tracking system was demonstrated. Mean camera path lengths were significantly different at 119,329px (juniors) versus 43,697px (seniors), P ≪ 0.05. The mean number of movements was significantly different at 9134 (juniors) versus 3690 (seniors), P ≪ 0.05. These quantifiable differences demonstrate construct validity for computer vision endoscope tracking as a measure of surgical experience. CONCLUSIONS: Computer vision tracking is a potentially useful structured and objective feedback tool to assist trainees in improving endoscope control. It enables juniors to examine how their pattern of endoscope control differs from that of seniors, focusing in particular on sections where they are most divergent.

Presoaking with BSS used for thin manually dissected DSEK (TMDSEK): a viable option for thin DSEK.

AIM: To describe a novel technique for the safe manual dissection of thin donor lenticules in 10 consecutive patients undergoing DSEK surgery. METHODS: A key element of our new technique was to presoak the donor cornea in balanced salt solution (BSS) for 30 min before manual dissection. The cornea was placed on an artificial anterior chamber and pressure in the chamber was maintained at 80 mm Hg. The limbus of the donor cornea was incised to the same depth as the central corneal thickness. Lamellar dissection was started with the short side of the Morlet dissector (Duckworth & Kent Ltd) and completed using the lamellar (less sharp) end of the Morlet dissector. Outcomes of 10 consecutive cases of thin manually dissected DSEK (TMDSEK) were prospectively analysed for thickness and visual outcome. RESULTS: Mean graft thicknesses measured less than 100 µm at 1 month post surgery (mean thickness 90.7 µm, range 48-137 µm, SD 29.96 µm). Presoaked donor corneal pachymetry was strongly negatively correlated with graft thickness (correlation r=-0.75, P<0.05). DISCUSSION: Our dissection technique achieves consistently thin endothelial donor corneal grafts that can be safely produced with minimal financial investment and no limitations on surgical time. This technique is likely to be of significant importance for a large proportion of the eye centres where microkeratomes may not be routinely available.

Advertencias en periódicos europeos para la salud pública sobre el riesgo de la retinopatía solar antes del eclipse solar de 2006 / Public health warnings of solar retinopathy risk in European newspapers prior to the 2006 solar eclipse

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