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One hundred consecutive cases of dry eye were studied to comment upon its epidemiological aspects. The incidence of dry eye amongst ophthalmic outpatients was 0.46% with a male:female ratio of 1:1.22. Fifty seven percent of the patients were above 50 years of age. The incidence was higher amongst outdoor workers and people from rural areas with poor socioeconomic status. The influence of hot and dry climate and nutritional status on dry eye incidence is discussed.

A clinico-investigative profile was studied in 30 patients with Graves′ Ophthalmopathy (GO) (15 each with early and late). In accordance to the thyroid status 63.3% of patients were hyperthyroid and 36.7% euthyroid. There was slight female preponderence, with ratio being 1.5:1. Exophthalmometric readings were significantly high in GO patients as compared to controls. However, no significant diagnostic role of postural exophthalmometry was seen. Positional tonometery may have respectable place among the tests for early diagnosis of GO; however, it could not differentiate between hyperthyroid and euthyroid cases. Further the role of ultrasonography, if available could not be overemphasized.

Bilateral proptosis due to metastatic Ewing′s sarcoma is an extremely rare presentation and thus merits reporting. The role of fine needle aspiration cytology in the diagnosis is highlighted.

The present double masked, randomized and placebo control study was carried out to compare the effects of steroids and an antiprostaglandin drug on aphakic cystoid macular oedema (ACME) in 60 cases who underwent uneventful intracapsular lens extraction. These 60 eyes were equally divided into three groups depending on the type of prophylactic eye drop instilled viz. Placebo group (I), steroid group (11) and in-domethacin group (III). Angiographic incidence of ACME observed in groups I, II and III was 40%, 10% and I0%, respectively. It is concluded that prophylactic treatment with topical steroids or indomethacin have a definite role to play in reducing the incidence as well as severity of ACME. Hence, their use is recommended for the prophylaxis- of ACHE. However, to justify the superiority of indomethacin or dexamethasone over each other a large and long term compara-tive studs is suggested.

A simple technique of combined gonio punch and intracapsular lens extraction with a fornix based conjunctival flap is described with encouraging results of pressure control (84%). It is ate as effective as trabeculectomy and an easy procedure for patients with cataract and either open or closed angle glaucoma The importance of frequent follow up in the post operative period especially in patients with primary open angle glaucoma emphasised.

A case of bloody tears in a young hysterical female is described and rarity of the condition is stressed.

Tear film flow and stability studies were carried out in healthy population by Schirmer′s test-1 and tear film break-up-time (BUT) measurements, respectively. The mean BUT observed was 13.87 +/- 4.79 seconds; however, in 22 percent of cases the values of BUT were even less than the lowest values laid down by various workers, from the Western countries. Maximum dry spots were located in the temporal quadrant.

The technique of transferring the momentum of optical potential landscapes to control the kinetics of the microscopic particles has recently gained considerable interest. In this paper, we report the optical micromanipulations of high and low indices particles using an optical trapping system integrated with a micron-sized double axicon. A double axicon is used to generate a self-imaged bottle beam, a propagation invariant beam. The transverse intensity profile of the self-imaged bottle beam oscillates along the propagation axis embedding three-dimensional intensity-null points, which are unique to conventional beams used in tweezers-like Gaussian, Laguerre-Gaussian, and Bessel beams. By imaging different portions of a self-imaged bottle beam, the same tweezers system can easily be modified for trapping applications of high and low indices microparticles. Furthermore, the self-reconstruction property of a self-imaged bottle beam is numerically studied and the minimum self-reconstruction distance of an obstructed self-imaged bottle beam is determined. [ABSTRACT FROM AUTHOR]

The article elucidates the physical mechanism behind the generation of superior-contrast and high-resolution label-free images using an optical waveguide. Imaging is realized by employing a high index contrast multi-moded waveguide as a partially coherent light source. The modes provide near-field illumination of unlabeled samples, thereby repositioning the higher spatial frequencies of the sample into the far-field. These modes coherently scatter off the sample with different phases and are engineered to have random spatial distributions within the integration time of the camera. This mitigates the coherent speckle noise and enhances the contrast (2–10) × as opposed to other imaging techniques. Besides, the coherent scattering of the different modes gives rise to fluctuations in intensity. The technique demonstrated here is named chip-based Evanescent Light Scattering (cELS). The concepts introduced through this work are described mathematically and the high-contrast image generation process using a multi-moded waveguide as the light source is explained. The article then explores the feasibility of utilizing fluctuations in the captured images along with fluorescence-based techniques, like intensity-fluctuation algorithms, to mitigate poor-contrast and diffraction-limited resolution in the coherent imaging regime. Furthermore, a straight waveguide is demonstrated to have limited angular diversity between its multiple modes and therefore, for isotropic sample illumination, a multiple-arms waveguide geometry is used. The concepts introduced are validated experimentally via high-contrast label-free imaging of weakly scattering nanosized specimens such as extra-cellular vesicles (EVs), liposomes, nanobeads and biological cells such as fixed and live HeLa cells.

Fenestrations in liver sinusoidal endothelial cells (LSEC) are transcellular nanopores of 50–350 nm diameter that facilitate bidirectional transport of solutes and macromolecules between the bloodstream and the parenchyma of the liver. Liver diseases, ageing, and various substances such as nicotine or ethanol can negatively influence LSECs fenestrations and lead to defenestration. Over the years, the diameter of fenestrations remained the main challenge for imaging of LSEC in vitro. Several microscopy, or rather nanoscopy, approaches have been used to quantify fenestrations in LSEC to assess the effect of drugs and, and toxins in different biological models. All techniques have their limitations, and measurements of the “true” size of fenestrations are hampered because of this. In this study, we approach the comparison of different types of microscopy in a correlative manner. We combine scanning electron microscopy (SEM) with optical nanoscopy methods such as structured illumination microscopy (SIM) or stimulated emission depletion (STED) microscopy. In addition, we combined atomic force microscopy (AFM) with SEM and STED, all to better understand the previously reported differences between the reports of fenestration dimensions. We conclude that sample dehydration alters fenestration diameters. Finally, we propose the combination of AFM with conventional microscopy that allows for easy super-resolution observation of the cell dynamics with additional chemical information that can be traced back for the whole experiment. Overall, by pairing the various types of imaging techniques that provide topological 2D/3D/label-free/chemical information we get a deeper insight into both limitations and strengths of each type microscopy when applied to fenestration analysis.