Optical Coherence Tomography Angiography Parameters in Indian Patients With Central Serous Chorioretinopathy

Background In this study, we aimed to evaluate optical coherence tomography angiography (OCTA) parameters among Indian patients affected with central serous chorioretinopathy (CSCR). Methodology A cross-sectional study on Indian patients having unilateral or bilateral affection with CSCR was conducted at the Department of Ophthalmology, Guru Nanak Eye Centre, and Maulana Azad Medical College, New Delhi. A history of ocular symptoms such as a diminution of vision, metamorphopsia, decreased contrast sensitivity (CS), and defective color vision (CV) and their duration were obtained. A detailed ocular examination for best-corrected visual acuity (BCVA), intraocular pressure (IOP), CV, and CS was done. Following this, fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed. OCT was done for central foveal thickness (CFT), subfoveal choroidal thickness (SFCT), neurosensory detachment (NSD), pigment epithelial detachment (PED), and choroidal neovascular membranes (CNVMs). The OCTA imaging was done to examine the foveal avascular zone (FAZ) size, perimeter and circularity, vessel density (VD), and features such as enlarged/distorted FAZ, dark areas, dark spots, abnormal vessels, and choriocapillaris island (CCI) in the retino-choroidal layers. We compared the OCTA features of affected eyes with those of fellow eyes. Results The study involved 52 eyes of 40 CSCR patients, including 32 (80%) males and eight (20%) females with a mean age of 39.3 ± 6.1 (24-49) years. Of the 40 patients, 12 (30%) had a bilateral involvement. The mean CFT was 300.3 ± 158.4 µ, and the SFCT was 258.5 ± 60.4 µ. The mean distance BCVA was the logarithm of the minimum angle of resolution (logMAR) 0.58 ± 0.32. The OCTA showed features such as enlarged/distorted FAZ (36.53% eyes), dark areas (NSD/PED) (84.61% eyes), dark spots (PED) (5.76% eyes), abnormal vessels (dilated vessels/CNVM) (96.15% eyes), and CCI (17.30% eyes). The mean FAZ area, perimeter, and circularity were 0.40 ± 0.71 mm2, 41.8 ± 280.0 mm, and 0.48 ± 0.12, respectively. The VD in the superficial capillary plexus (SCP) was 25.4 ± 14.1, deep capillary plexus (DCP) 15.0 ± 11.5, outer retina (OR) 5.9 ± 6.8, outer retinal choriocapillaris (ORCC) 33.7 ± 16.9, choriocapillaris 29.7 ± 17.5, and choroid 29.9 ± 17.5. The fellow eyes showed a mean FAZ area, perimeter, and circularity of 0.34 ± 0.23 mm2, 76.8 ± 391.2 mm, and 0.47 ± 0.11, respectively, while VD of SCP was 25.9 ± 13.6, DCP 16.5 ± 11.7, OR 14.3 ± 14.9, ORCC 38.0 ± 16.5, choriocapillaris 36.3 ± 17.7, and choroid 35.5 ± 19.2. Conclusions The CSCR eyes had a thicker fovea and sub-foveal choroid (SFC). The FAZ area of affected eyes was larger, while the perimeter was smaller than that in the fellow eye. In the affected eye, the VD in all the retino-choroidal layers was lower, although it was significantly reduced in OR whole (p = 0.006) and foveal choroid (p = 0.022).

Quantum oscillations in an optically-illuminated two-dimensional electron system at the LaAlO3/SrTiO3interface

We have investigated the illumination effect on the magnetotransport properties of a two-dimensional electron system at the LaAlO₃/SrTiO₃interface. The illumination significantly reduces the zero-field sheet resistance, eliminates the Kondo effect at low-temperature, and switches the negative magnetoresistance into the positive one. A large increase in the density of high-mobility carriers after illumination leads to quantum oscillations in the magnetoresistance originating from the Landau quantization. The carrier density (∼2 × 10¹² cm^-2) and effective mass (∼1.7m_e) estimated from the oscillations suggest that the high-mobility electrons occupy thed_xz/yzsubbands of Ti:t_2gorbital extending deep within the conducting sheet of SrTiO₃. Our results demonstrate that the illumination which induces additional carriers at the interface can pave the way to control the Kondo-like scattering and study the quantum transport in the complex oxide heterostructures.

Lifetime of a Nanodroplet: Kinetic Effects and Regime Transitions

A transition from a d^{2} to a d law is observed in molecular dynamics (MD) simulations when the diameter (d) of an evaporating droplet reduces to the order of the vapor's mean free path; this cannot be explained by classical theory. This Letter shows that the d law can be predicted within the Navier-Stokes-Fourier (NSF) paradigm if a temperature-jump boundary condition derived from kinetic theory is utilized. The results from this model agree with those from MD in terms of the total lifetime, droplet radius, and temperature, while the classical d^{2} law underpredicts the lifetime of the droplet by a factor of 2. Theories beyond NSF are also employed in order to investigate vapor rarefaction effects within the Knudsen layer adjacent to the interface.

Mucinous cystadenoma: A rare entity

Cystadenoma is a rare benign salivary gland tumor that chiefly originates in the minor salivary glands as a cystic growth with papillary projections into the cystic lumen without the lymphoid element. It is further classified into two histopathological variants that have been recognized by World Health Organization as the papillary and the mucinous forms of cystadenoma. Clinically, it is difficult to differentiate from other benign minor salivary tumors and mucous retention phenomenon. Diagnosis is chiefly based on characteristics histological features. It is believed that the salivary gland tumors are difficult to diagnose and interpret because there are varied patterns of presentation. The study of salivary gland disorders has increased in leaps and bounds. The authors report a case of mucinous cystadenoma of the minor salivary gland on the hard palate, which is even rarest of the rarely reported cystadenomas of the minor salivary glands.

Unusual presentation of caustic ingestion and its surgical treatment: a case report

Treatment and reconstruction of oral scar contracture, is always a challenging procedure to restore structure and functions of the oral cavity. We present a case of a patient with limited mouth opening who sustained extensive oral scar contracture with complete adhesion of tongue to floor of mouth following ingestion of caustic soda without his knowledge 4 years back. We performed a surgical release of the scar contractures from buccal mucosa on both sides, along with a release of the tongue from the floor of the mouth, followed by reconstruction of all sites using split skin grafts. Adequate mouth opening and tongue movement was achieved. There was a follow up period of 1 month with excellent mouth opening and tongue function.

Intraosseous neurofibroma of maxilla in a child

Central tumors of neurogenic origin are among the most rare primary jaw tumors in children. Intraosseous neurofibromas of the jaws occur more often as solitary lesions rather than as part of a generalized neurofibromatosis. We are presenting a case of solitary intraosseous neurofibroma of the maxilla in a five-month-old infant, which is probably the youngest such case published in literature so far.