Shruti Aggarwal

Bio: Shruti Aggarwal is an academic researcher from Massachusetts Eye and Ear Infirmary. The author has contributed to research in topics: Cornea & Materials science. The author has an hindex of 13, co-authored 39 publications receiving 502 citations. Previous affiliations of Shruti Aggarwal include Harvard University & MetroWest Medical Center.

SARS-CoV-2 Impact on Elective Orthopaedic Surgery: Implications for Post-Pandemic Recovery.

Abstract: BACKGROUND: The aim of our study was to explore the impact of elective-surgery deferment on the United States health-care system and subsequent recovery after COVID-19 containment. Using an orthopaedic elective surgery model, we aimed to answer the following: (1) What is the expected recovery time until the health-care system is back to nearly full capacity for performing elective surgery? (2) What will be the expected backlog of elective surgery over time? (3) How should health care change to address the backlog? METHODS: A Monte Carlo stochastic simulation-based analysis was performed to forecast the post-pandemic volume of elective, inpatient total joint arthroplasty and spinal fusion surgical cases. The cumulative backlog was calculated and analyzed. We tested model assumptions with sensitivity analyses. RESULTS: Assuming that elective orthopaedic surgery resumes in June 2020, it will take 7, 12, and 16 months-in optimistic, ambivalent, and pessimistic scenarios, respectively-until the health-care system can perform 90% of the expected pre-pandemic forecasted volume of surgery. In the optimistic scenario, there will be a cumulative backlog of >1 million surgical cases at 2 years after the end of elective-surgery deferment. CONCLUSIONS: The deferment of elective surgical cases during the SARS-CoV-2 pandemic will have a lasting impact on the United States health-care system. As part of disaster mitigation, it is critical to start planning for recovery now.

Autologous Serum Tears for Treatment of Photoallodynia in Patients with Corneal Neuropathy: Efficacy and Evaluation with In Vivo Confocal Microscopy

Abstract: Objective Patients suffering from corneal neuropathy may present with photoallodynia; i.e., increased light sensitivity, frequently with a normal slit-lamp examination. This study aimed to evaluate the efficacy of autologous serum tears (AST) for treatment of severe photoallodynia in corneal neuropathy and to correlate clinical findings with corneal subbasal nerve alterations by in vivo confocal microscopy (IVCM). Methods Retrospective case control study with 16 patients with neuropathy-induced severe photoallodynia compared to 16 normal controls. Symptom severity, clinical examination and bilateral corneal IVCM scans were recorded. Results All patients suffered from extreme photoallodynia (8.8±1.1) with no concurrent ocular surface disease. Subbasal nerves were significantly decreased at baseline in patients compared to controls; total nerve length (9208±1264 vs 24714±1056 μm/mm 2 ; P 2 ), number (13.9±2.1), and reflectivity (1.9±0.1). Beading and neuromas were seen in only 56.2% and 7.6% of patients. Conclusion Patients with corneal neuropathy-induced photoallodynia show profound alterations in corneal nerves. AST restores nerve topography through nerve regeneration, and this correlated with improvement in patient-reported photoallodynia. The data support the notion that corneal nerve damage results in alterations in afferent trigeminal pathways to produce photoallodynia.

Dry Eye Syndrome in Menopause and Perimenopausal Age Group.

Abstract: Dry eye disease (DED) is a multifactorial ocular surface disease that causes symptoms of ocular pain, discomfort, and decreased visual acuity. It significantly affects quality of life of patients. It is more prevalent in the females and is being specifically in the menopausal and postmenopausal age group. This is believed to be due to the changes in balance of sex hormones. Sex hormones - estrogens and androgens - influence production of all components of the tear film including aqueous layer, lipid, and mucin. Various mechanisms such as decrease in hormonal levels, shift in feedback mechanisms, and changes in receptor receptivity interplay to alter the ocular surface homeostasis and subsequently result in DED. Several studies have suggested potential role of hormone replacement therapy in menopause-associated dry eye symptoms. The purpose of this review is to help the non ophthalmic physicians about DED encountered commonly in menopausal age group. It is important for primary care physicians to understand DED due to its high prevalence, often debilitating symptoms and the potentially preventable and treatable nature of the condition.

Efficacy of autologous serum tears for treatment of neuropathic corneal pain

Abstract: Objective Corneal nerve damage may result in neuropathic corneal pain (NCP). Autologous serum tears (AST) have been shown to results in nerve regeneration and may help alleviate corneal pain. This study aimed to evaluate the efficacy of AST in the treatment of NCP. Methods This was a retrospective case-control study. Sixteen patients suffering from severe NCP and no current ocular surface disease were compared to 12 controls. In vivo confocal microscopy (IVCM) (HRT3/RCM; Heidelberg Engineering GmbH, Germany) of the central corneas was performed bilaterally. Change in pain severity (scale of 0–10), corneal nerve density, tortuosity, reflectivity and presence of beading and micro-neuromas before and after treatment were recorded. Results All patients had severe pain, with a mean of 9.1 ± 0.2 (range 8–10). Subbasal nerves were significantly decreased before treatment as compared to controls, including total nerve length (10,935.5 ± 1264.3 vs. 24,714.4 ± 1056.2 μm/mm2; p Conclusion IVCM demonstrates underlying alterations of the subbasal corneal nerve plexus in patients suffering from debilitating NCP. AST-induced nerve regeneration is seen following treatment with AST, which correlates with improvement in patient symptoms of NCP.

Pattern Recognition and Machine Learning

Abstract: Probability Distributions.- Linear Models for Regression.- Linear Models for Classification.- Neural Networks.- Kernel Methods.- Sparse Kernel Machines.- Graphical Models.- Mixture Models and EM.- Approximate Inference.- Sampling Methods.- Continuous Latent Variables.- Sequential Data.- Combining Models.

TFOS DEWS II Management and Therapy Report

Abstract: The members of the Management and Therapy Subcommittee undertook an evidence-based review of current dry eye therapies and management options. Management options reviewed in detail included treatments for tear insufficiency and lid abnormalities, as well as anti-inflammatory medications, surgical approaches, dietary modifications, environmental considerations and complementary therapies. Following this extensive review it became clear that many of the treatments available for the management of dry eye disease lack the necessary Level 1 evidence to support their recommendation, often due to a lack of appropriate masking, randomization or controls and in some cases due to issues with selection bias or inadequate sample size. Reflecting on all available evidence, a staged management algorithm was derived that presents a step-wise approach to implementing the various management and therapeutic options according to disease severity. While this exercise indicated that differentiating between aqueous-deficient and evaporative dry eye disease was critical in selecting the most appropriate management strategy, it also highlighted challenges, based on the limited evidence currently available, in predicting relative benefits of specific management options, in managing the two dry eye disease subtypes. Further evidence is required to support the introduction, and continued use, of many of the treatment options currently available to manage dry eye disease, as well as to inform appropriate treatment starting points and understand treatment specificity in relation to dry eye disease subtype.

TFOS DEWS II pain and sensation report

Abstract: Pain associated to mechanical and chemical irritation of the eye surface is mediated by trigeminal ganglion mechano- and polymodal nociceptor neurons while cold thermoreceptors detect wetness and reflexly maintain basal tear production and blinking rate. These neurons project into two regions of the trigeminal brain stem nuclear complex: ViVc, activated by changes in the moisture of the ocular surface and VcC1, mediating sensory-discriminative aspects of ocular pain and reflex blinking. ViVc ocular neurons project to brain regions that control lacrimation and spontaneous blinking and to the sensory thalamus. Secretion of the main lacrimal gland is regulated dominantly by autonomic parasympathetic nerves, reflexly activated by eye surface sensory nerves. These also evoke goblet cell secretion through unidentified efferent fibers. Neural pathways involved in the regulation of Meibonian gland secretion or mucins release have not been identified.In dry eye disease, reduced tear secretion leads to inflammation and peripheral nerve damage. Inflammation causes sensitization of polymodal and mechano-nociceptor nerve endings and an abnormal increase in cold thermoreceptor activity, altogether evoking dryness sensations and pain. Long-term inflammation and nerve injury alter gene expression of ion channels and receptors at terminals and cell bodies of trigeminal ganglion and brainstem neurons, changing their excitability, connectivity and impulse firing. Perpetuation of molecular, structural and functional disturbances in ocular sensory pathways ultimately leads to dysestesias and neuropathic pain referred to the eye surface. Pain can be assessed with a variety of questionaires while the status of corneal nerves is evaluated with esthesiometry and with in vivo confocal microscopy.

Revisiting the vicious circle of dry eye disease: a focus on the pathophysiology of meibomian gland dysfunction

Abstract: Meibomian gland dysfunction (MGD) is the most frequent cause of dry eye disease (DED). Eyelid inflammation, microbial growth, associated skin disorders as well as potentially severe corneal complications culminate to make MGD a complex multifactorial disorder. It is probable that MGD is a heterogeneous condition arising from any combination of the following five separate pathophysiological mechanisms: eyelid inflammation, conjunctival inflammation, corneal damage, microbiological changes and DED resulting from tear film instability. The pathogenesis of both MGD and DED can be described in terms of a 'vicious circle': the underlying pathophysiological mechanisms of DED and MGD interact, resulting in a double vicious circle. The MGD vicious circle is self-stimulated by microbiological changes, which results in increased melting temperature of meibum and subsequent meibomian gland blockage, reinforcing the vicious circle of MGD. Meibomian gland blockage, dropout and inflammation directly link the two vicious circles. MGD-associated tear film instability provides an entry point into the vicious circle of DED and leads to hyperosmolarity and inflammation, which are both a cause and consequence of DED. Here we propose a new pathophysiological scheme for MGD in order to better identify the pathological mechanisms involved and to allow more efficient targeting of therapeutics. Through better understanding of this scheme, MGD may gain true disease status rather than being viewed as a mere dysfunction.