Rodent models for dry eye syndrome: Standardization using benzalkonium chloride and scopolamine hydrobromide.

Dry eye disease is a highly prevalent ocular condition that significantly affects the quality of life and presents a major challenge in ophthalmology. Animal models play a crucial role in investigating the pathophysiology and developing effective treatments. The goal of this study was to compare and standardize two dry eye disease rodent models and explore their recovery aspects. We have standardized benzalkonium chloride and scopolamine-induced dry eye disease models which represents two different classes of the dry eye i.e., evaporative dry eye and aqueous deficient dry eye, respectively. After the development of dry eye conditions, a self-recovery period of seven days was granted to assess the reversal of the induced changes. The dry eye condition was assessed by measuring tear volume, corneal slit lamp imaging, and histological examination of the cornea, the lacrimal and the harderian gland. The study indicated the development of chronic inflammation of the cornea and lacrimal gland in the case of benzalkonium after five days of the treatment, while the scopolamine treated group showed chronic inflammation of the lacrimal gland after five days and corneal inflammation after seven days of administration. The recovery study suggested that after discontinuation of inducing agent, the dry eye symptoms were still persistent suggesting the utility of the model in evaluating dry eye treatments. The study highlights the comparative changes in both models along with recovery which can serve as a base for drug discovery and development against dry eye disease.

The effect of different thickness scleral lens on corneal parameters in eyes with keratoconus.

Purpose: To investigate the impact of different-thickness scleral lenses (SLs) on corneal thickness, curvature, and fluid reservoir thickness in keratoconic eyes. Methods: Schiempflug imaging and AS-OCT was captured before and immediately following 6 h of SL wear. Different-thickness lenses were used while keeping the other parameters the same. The timing of the measurement for day 1 and day 2 was matched to allow for the control of the confounding influence of diurnal variation. Results: Immediately after 6 h of lens wear, no statistically significant difference (P > 0.05) was noted in corneal edema in any region and quadrants between thin- and thick-lens wearers. The calculated percentage of corneal edema was also within the range of overnight closed eye physiological swelling. Pentacam measured higher central corneal thickness compared to AS-OCT in both baselines and after 6 h of lens wear. The current investigation reported minimal but not statistically significant (P > 0.05) flattening in anterior and steepening in posterior curvature parameters in both thin and thick SLs. The mean reduction in the fluid reservoir thickness was 80.00 ± 3.99 and 79.36 ± 3.84 microns after 6 h of thin- and thick-lens wear, respectively, which was not statistically significant (P > 0.05). A statistically significant positive correlation (r = 0.67, P = 0.02) was found between lens thickness and change in anterior steep k with thick-lens wear. Conclusion: Central lens thickness of 200-400 µm did not cause any significant change in corneal curvature and fluid reservoir thickness and did not induce clinically significant corneal edema after short-term SL wear.

Role of HRCT Temporal Bone in Predicting Surgical Difficulties Encountered in Fenestral Otosclerosis Surgery.

To study spectrum of high resolution computed tomography (HRCT) imaging findings in otosclerosis, to predict approximate length of prosthesis required from pre-operative HRCT measurements and to correlate between oval window niche (OWN) height preoperatively and difficulty in introducing foot plate perforator during surgery. A cross sectional study was conducted on 23 patients with a clinical diagnosis of otosclerosis from September 2018 to July 2020. Sensitivity of HRCT in detecting otosclerosis, correlation between pre-operative incudo-stapedial length (ISL) and intra operative prosthesis length, and correlation between OWN height and difficulty in introducing perforator were sought. The mean age of 23 patients studied was 39.9 years with a female preponderance of 56.5%. 17 out of 19 patients with foci of otosclerosis during surgery had HRCT findings of otosclerosis providing a sensitivity of 89.5%. Mean OWN height obtained was 1.29 mm preoperatively and a cut off value of 1.325 mm found using receiver operating characteristic curve method classifying OWN height as narrow or normal. Mean ISL measured pre operatively was 4.25 mm and mean length of prosthesis used was 4.56 mm with significant positive correlation using intraclass correlation coefficient method with correlation coefficient = 0.879. HRCT is an invaluable modality aiding the surgeon to detect otosclerotic foci with high sensitivity, identify thick obliterative otosclerotic foci requiring additional drilling, to predict the length of prosthesis used and to predict difficulties in approaching footplate when OWN height is below 1.325 mm.

Finite Element Analysis of Cornea and Lid Wiper during Blink, with and without Contact Lens.

Ocular surface disorders such as Lid Wiper Epitheliopathy (LWE), Superior Epithelial Arcuate Lesion (SEAL), and contact lens-induced Limbal Stem Cell Deficiency (LSCD) as well as Superior Limbic Keratoconjunctivitis (SLK) affect one's quality of life. Hence, it is imperative to investigate the underlying causes of these ocular surface disorders. During blink, the undersurface of the eyelid tends to interact with the cornea and the conjunctiva. The presence of a contact lens can add to the biomechanical frictional changes on these surfaces. To estimate these changes with and without a contact lens, a finite element model (FEM) of the eyelid wiper, eyeball, and contact lens was developed using COMSOL Multiphysics. Biomechanical properties such as von Mises stress (VMS) and displacement were calculated. Our study concluded that (a) maximum VMS was observed in the lid wiper in the absence of contact lens in the eye and (b) maximum VMS was observed in the superior 1.3 mm of the cornea in the presence of the contact lens in the eye. Thus, the development of friction-induced ocular surface disorders such as LWE, SLK, SEAL, and LSCD could be attributed to increased VMS. FEA is a useful simulation tool that helps us to understand the effect of blink on a normal eye with and without CL.

Impact of modulus of elasticity of silicone hydrogel contact lenses on meibomian glands morphology and function.

Clinical relevance: It is important to investigate the effect of modulus of silicone hydrogel contact lens on meibomian glands. Evaluating meibomian gland health and function in follow-up appointments should be considered, with the option of changing lens modulus.Background: To evaluate and compare the effect of modulus of elasticity of silicone hydrogel contact lenses on morphological and functional parameters of the meibomian glands.Methods: A prospective study was conducted on soft silicone hydrogel contact lens wearers of different modulus of elasticity and age and gender-matched controls. Morphological and functional parameters were assessed along with standard patient evaluation of the eye dryness questionnaire.Results: A statistically significant difference was noted in meibomian gland loss in the upper lid (percent) between the low modulus (18.23 ± 6.63) and high modulus group (27.40 ± 10.21) (p < 0.001) and between high modulus (27.40 ± 10.21) and non-contact lens wearers (19.57 ± 7.65) (p = 0.001). The current study reported significantly higher total meiboscore grading in the high modulus group 3 (2-3) compared to the low modulus 2(2-3) (p = 0.007) and non-contact lens wearing groups 2 (2-3) (p = 0.012). Meibum quality was significantly compromised in the high modulus group 1 (0-1) compared to the low modulus 0 (0-0.75) group (p = 0.01). Standard patient evaluation of the eye dryness questionnaire was found to be significantly higher (p = 0.01) in high modulus 4 (2-8) compared to low modulus wearers 2 (2-4). A significant difference was noted (p < 0.001) in corneal staining grading only between high modulus 0 (0-1) and non-contact lens wearers 0 (0-0) group. A positive correlation was noted in the low modulus group between total meiboscore and meibomian gland expressibility (Rs = +0.69, p < 0.001) and also noted between standard patient evaluation of the eye dryness questionnaire scoring and meibomian gland expressibility (Rs = +0.45, p = 0.012) in the high modulus group.Conclusion: Higher modulus of elasticity of silicone hydrogel contact lens may influence meibomian gland morphology and function over a period of contact lens wear.

Siblings with megalencephalic leukoencephalopathy with subcortical cysts van der Knaap disease.

Cerebral leukoencephalopathy and megalencephaly with subcortical cysts (also known as van der Knaap disease) is an autosomal recessive condition. The disease was initially described in India and Netherlands independently and seems to have highest incidence in Indian Agrawal community and Turkish population.1 The objective of this study is to document the case of two siblings with this condition, from a non-Agrawal Indian community and briefly describe the imaging features of this condition. Two siblings, born out of a third-degree consanguineous marriage, with simple focal seizures were subjected to MRI with diffusion-weighted imaging and spectrometry. The findings were compared to diseases with similar clinical presentation. Subcortical cysts initially involving anterior temporal lobes and subsequently frontal and parietal lobes, sparing of central white mater, small N acetyl aspartate peak and diffusion facilitation were the imaging findings. The imaging findings were consistent with the diagnosis of the rare genetic disorder- Cerebral leukoencephalopathy and megalencephaly with subcortical cysts.

Dermatomyositis associated with adenocarcinoma of the lung: A case report.

The association of dermatomyositis and underlying malignancies, especially small cell and squamous cell carcinoma of the lung, has been recognized a long time ago. We report the case of a 63-year-old male chronic smoker with adenocarcinoma lung associated with dermatomyositis. The occurrence of dermatomyositis should be considered as a potential presentation of paraneoplastic syndromes and physicians encountering similar clinical situations should perform extensive diagnostic work-up to exclude underlying neoplastic lesions.

Moulding Faces at an Early Age-A Case Series.

Certain malocclusions have to be treated at an early age to avoid surgeries for the correction in the future. Introduction of functional appliances has reduced the elimination and correction of skeletal as well as dental discrepancies. Proper case selection taking into consideration skeletal and dental age with the use of various diagnostic aids helps us to identify and treat the malocclusions before it is too late. In this case series, we report three patients with skeletal jaw malrelationship treated with functional and orthopaedic appliances.

SciReader enables reading of medical content with instantaneous definitions.

BACKGROUND: A major problem patients encounter when reading about health related issues is document interpretation, which limits reading comprehension and therefore negatively impacts health care. Currently, searching for medical definitions from an external source is time consuming, distracting, and negatively impacts reading comprehension and memory of the material. METHODS: SciReader was built as a Java application with a Flex-based front-end client. The dictionary used by SciReader was built by consolidating data from several sources and generating new definitions with a standardized syntax. The application was evaluated by measuring the percentage of words defined in different documents. A survey was used to test the perceived effect of SciReader on reading time and comprehension. RESULTS: We present SciReader, a web-application that simplifies document interpretation by allowing users to instantaneously view medical, English, and scientific definitions as they read any document. This tool reveals the definitions of any selected word in a small frame at the top of the application. SciReader relies on a dictionary of ~750,000 unique Biomedical and English word definitions. Evaluation of the application shows that it maps ~98% of words in several different types of documents and that most users tested in a survey indicate that the application decreases reading time and increases comprehension. CONCLUSIONS: SciReader is a web application useful for reading medical and scientific documents. The program makes jargon-laden content more accessible to patients, educators, health care professionals, and the general public.