636 results on '"Amar Agarwal"'
Search Results
2. Pre-Descemet's endothelial keratoplasty with glued intraocular lens implantation with pinhole pupilloplasty in a case of ocular comorbidity in achromatopsia
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Dhivya Ashok Kumar, Amar Agarwal, and Swetha Ravichandran
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aphakia with corneal decompensation and keratoconus ,glued intraocular lens implantation ,pinhole pupilloplasty ,pre-descemet's endothelial keratoplasty ,single-pass four-throw pupilloplasty ,triple procedure ,Ophthalmology ,RE1-994 - Abstract
Ocular comorbidities can happen as congenital defective gene associations. We present a 37-year-old female patient who was mentally challenged and had coexisting achromatopsia gene abnormality on genetic analysis. She was operated in childhood for congenital cataract, and posterior chamber intraocular lens (IOL) was implanted at 10 years of age elsewhere. The patient presented 27 years later with luxated IOL with endothelial decompensation. There was a coexisting steep and thin cornea noted on corneal topography. She was managed with pre-Descemet's endothelial keratoplasty with transpositioning of posterior chamber IOL to glued IOL with single-pass four-throw pupilloplasty. Postoperatively, the cornea was clear with centered glued IOL. The lesser postanesthetic challenges and faster rehabilitation are obtained in combination procedures with reduced complications in such rare scenarios.
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- 2024
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3. Customized corneal allogenic intrastromal ring segments (CAIRS) for keratoconus with decentered asymmetric cone
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Soosan Jacob, Amar Agarwal, Shady T Awwad, Cosimo Mazzotta, Parnika Parashar, and Sambath Jambulingam
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asymmetric icrs ,asymmetric cairs ,contact lens-assisted corneal crosslinking ,cairs ,corneal allogenic intrastromal ring segment ,corneal crosslinking ,cacxl ,customized cairs ,ectasia ,icrs ,intra corneal ring segment ,intacs ,kerarings ,keratoconus ,progressive thickness cairs ,shaped cairs ,tapered cairs ,variable thickness cairs ,Ophthalmology ,RE1-994 - Abstract
Corneal allogenic intrastromal ring segments (CAIRS) refer to the intracorneal placement of fresh,unprocessed, processed, preserved, or packaged allogenic rings/segments of any type/length. We described uniform-thickness CAIRS previously. We now describe a new technique of customized CAIRS to personalize the flattening effect as per individual topography. A prospective interventional case series of patients with pericentral/ paracentral decentered cones and gradation of keratometry with one side steeper than the other was conducted. Individually customized tapered CAIRS with variable volume, arc length, taper length, and gradient of taper were implanted. In total, 32 eyes of 29 patients with at least 1-year follow-up were included. Special double-bladed trephines and a CAIRS customizer template allowed the creation of individually customized CAIRS. Mean uncorrected distance visual acuity (UDVA) and spectacle-corrected distance visual acuity improved from 0.22 to 0.47 (P = 0.000) and from 0.76 to 0.89 (P = 0.001), respectively. Significant improvement was seen in K1, K2, Km, Kmax, topographic astigmatism, Q-value, sphere, cylinder, spherical equivalent, Root Mean Square (RMS), Higher Order Aberrations (HOA), and vertical coma (P < 0.01, 0.05). There was no significant change in the width or height of CAIRS between 1 month and last visit on anterior-segment optical coherence tomography. Five eyes continued to remain at the same UDVA, 27 eyes had at least 2 lines, and 13 eyes had at least 3 or more lines improvement in UDVA. The maximum improvement in UDVA was 7 lines. A significant difference in flattening was obtained at different zones across the tapered CAIRS. Thus, differential flattening was achieved across the cone based on the customization plan. Personalized customization was possible for each cornea, unlike limited models of progressive-thickness synthetic segments. Allogenic nature, greater customizability, efficacy, and absent need for large inventories are advantages compared to synthetic segments.
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- 2023
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4. Phacoemulsification, pinhole pupilloplasty, and pre-Descemet's endothelial keratoplasty for keratoconus with Fuchs' endothelial dystrophy
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Dhivya Ashok Kumar, Soosan Jacob, Preethi Naveen, Soundari Sivagnanam, and Amar Agarwal
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fuchs' endothelial dystrophy ,irregular astigmatism ,keratoconus ,pinhole pupilloplasty ,pre-descemet's endothelial keratoplasty ,Ophthalmology ,RE1-994 - Abstract
The comorbidity of keratoconus with Fuchs' endothelial dystrophy with cataract is a rare clinical combination. We present an amalgamation of surgical techniques to manage the above clinical conditions and its complications in single setting. The modified triple procedure, namely, the phacoemulsification, pinhole pupilloplasty, and pre-Descemet's endothelial keratoplasty (PDEK) in the order of description is followed in single sitting. Lens removal by phacoemulsification, correction of irregular astigmatism by pinhole pupilloplasty (pinhole optics), and exchanging the endothelial layer for PDEK forms the main segments of the triple procedure. This combination of techniques may decrease the risk of multiple surgeries and its related complications. Moreover, it will allow the patient for faster visual rehabilitation by improving the uncorrected visual acuity and visual quality.
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- 2023
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5. Hypersonic vitrectomy in intraoperative posterior capsular rupture with retained nuclear fragments
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Dhivya Ashok Kumar, Amar Agarwal, Ashvin Agarwal, and Asael Papour
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anterior vitrectomy ,hypersonic vitrectomy ,intraoperative posterior capsular rupture retained nuclear fragments ,Ophthalmology ,RE1-994 - Abstract
In our report, we present the hypersonic vitrectomy (Vitesse, Bausch and Lomb) being employed for anterior vitreous liquefaction and removal in posterior capsular rupture. The capsular tear with nucleus drop during conventional phacoemulsification was managed by vitrectomy using the hypersonic vitrector after posterior-assisted levitation followed by intraocular lens (IOL) implantation. The minimal cortical and epinuclear lens particles in the anterior chamber and vitreous were also liquefied with a stoke length of 30 to 40 μm and aspirated via the Vitesse vitrectomy system. The same probe performs the vitrectomy and the nucleus removal. The postoperative period was uneventful with clear cornea, normal fundus, and 20/20 best-corrected visual acuity (BCVA). The hypersonic vitrectomy utilizes the ultrasound power of 29.5 kHz and a stoke length of 0 to 60 μm for liquefaction of the vitreous. It can be a safe alternative for vitrectomy and lens removal in a single setting.
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- 2023
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6. Comparative Analysis of 10-2 Test on Advanced Vision Analyzer and Humphrey Perimeter in Glaucoma
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Priya Narang, MS, Amar Agarwal, FRCS, FRCOphth, Ashvin Agarwal, MS, Rhea Narang, and Lavanya Sundaramoorthy, Optom
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Advanced vision analyzer ,AVA ,HFA ,Visual field test ,VR perimeter ,Ophthalmology ,RE1-994 - Abstract
Purpose: To evaluate diagnostic precision and prove equivalence of 2 devices, Advanced vision analyzer (AVA, Elisar Vision Technology) and Humphrey field analyzer (HFA, Zeiss) for the detection of glaucoma on 10-2 program. Design: Prospective, cross-sectional, observational study. Participants: Threshold estimates of 1 eye each of 66 patients with glaucoma, 36 control participants, and 10 glaucoma suspects were analyzed on 10-2 test with AVA and HFA. Methods: Mean sensitivity (MS) values of 68 points and central 16 test points were calculated and compared. Intraclass correlation (ICC), Bland–Altman (BA) plots, linear regression of MS, mean deviation (MD), and pattern standard deviation (PSD) were computed to assess the 10-2 threshold estimate of the devices. Receiver operating characteristic curves were generated for MS and MD values, and the area under the curve (AUC) was compared with assessing diagnostic precision. Main Outcome Measures: Mean sensitivity values of 68 points and central 16 points, AUC for MS and MD values, ICC values, BA plots, and linear-regression analysis. Results: Bland–Altman plot showed significant correlation for MS, MD, and PSD values for both devices. For MS, the overall ICC value was 0.96 (P < 0.001) with a mean bias of 0.0 dB and limits of agreement range of 7.59. The difference in MS values between both devices was −0.4760 ± 1.95 (P > 0.05). The AUC for MS values for AVA was 0.89 and for HFA was 0.92 (P = 0.188); whereas it was similar at 0.88 for MD values (P = 0.799). Advanced vision analyzer and HFA identically discriminated between healthy and patients with glaucoma (P < 0.001), although HFA denoted marginally greater ability (P > 0.05). Conclusions: Statistical results denote adequate equivalence between AVA and HFA because threshold estimates of AVA strongly correlate with HFA for 10-2 program. Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references.
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- 2023
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7. A case of central retinal artery occlusion due to atrial myxoma with excellent visual recovery
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Santosh Balasubramaniam, Janani Sreenivasan, Atul Dhawan, and Amar Agarwal
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central retinal artery occlusion ,emergency management ,left atrial myxoma ,leading fluorescein sign ,systemic thromboembolism ,visual recovery ,Ophthalmology ,RE1-994 - Published
- 2022
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8. A new normal with cataract surgery during COVID-19 pandemic
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Jagadesh C Reddy, Pravin K Vaddavalli, Namrata Sharma, Mahipal S Sachdev, Y L Rajashekar, Rajesh Sinha, Amar Agarwal, Amit Porwal, Arup Chakrabarti, Barun Kumar Nayak, Bhudhendra Kumar Jain, D Chandrasekhar, Chitra Ramamurthy, Cyres Keiki Mehta, Debasish Bhattacharya, Gaurav Luthra, Haripriya Aravind, Harsha Bhattacharjee, Himanshu Rasiklal Mehta, J S Titiyal, Jagat Ram, Jatinder Singh Bhalla, Keerthi Kumar Dasari, Keiki R Mehta, Krishna Prasad Kudlu, R Krishna Prasad, Kumaran Murugesan, Mandeep Jot Singh, Mohan Rajan, Om Parkash Rohit, Parikshit Gogate, Partha Biswas, Prema Padmanabhan, Ragini Hasmukuray Parekh, Rohit Khanna, Santosh G Honavar, Somasheila I Murthy, Sonu Goel, Sri Ganesh, and Vinod Kumar Arora
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cataract ,covid-19 ,pandemic ,phacoemulsification ,sars-cov-2 ,Ophthalmology ,RE1-994 - Abstract
Cataract is the second leading cause of preventable blindness on the globe. Several programs across the country have been running efficiently to increase the cataract surgical rates and decrease blindness due to cataract. The current COVID-19 pandemic has led to a complete halt of these programs and thus accumulating all the elective cataract procedures. At present with the better understanding of the safety precautions among the health care workers and general population the Government of India (GoI) has given clearance for functioning of eye care facilities. In order to facilitate smooth functioning of every clinic, in this paper, we prepared preferred practice pattern based on consensus discussions between leading ophthalmologists in India including representatives from major governmental and private institutions as well as the All India Ophthalmological Society leadership. These guidelines will be applicable to all practice settings including tertiary institutions, corporate and group practices and individual eye clinics. The guidelines include triage, use of personal protective equipment, precautions to be taken in the OPD and operating room as well for elective cataract screening and surgery. These guidelines have been prepared based on current situation but are expected to evolve over a period of time based on the ongoing pandemic and guidelines from GoI.
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- 2020
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9. Advanced Vision Analyzer–Virtual Reality Perimeter
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Priya Narang, MS, Amar Agarwal, FRCS, FRCOphth, Maheswari Srinivasan, MOptom, FIACLE, and Ashvin Agarwal, MS
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Advanced vision analyzer ,AVA ,Elisar ,Elisar Standard ,HFA ,Humphrey Field Analyzer ,Ophthalmology ,RE1-994 - Abstract
Purpose: To evaluate the Advanced Vision Analyzer (AVA; Elisar Vision Technology) and to compare pointwise threshold sensitivity and functional correlation of Elisar Standard Algorithm (ESA) with the Swedish Interactive Threshold Algorithm (SITA) of the Humphrey Field Analyzer (HFA; Carl Zeiss Meditec, Inc). Design: Prospective, cross-sectional, observational case series. Participants: One hundred sixty eyes (85 control participants, 75 glaucoma patients) for functional assessment, 15 eyes for test–retest variability (TRV), 107 eyes for blind spot trial (45 normal eyes, 62 glaucoma eyes) were recruited consecutively. A separate group of participants was chosen for each assessment. Methods: All participants underwent ESA and SITA Standard 24-2 testing, and 1 eye of each participant was selected randomly. Intraclass correlation coefficient (ICC), Bland-Altman, linear regression, mean bias (MB), and proportional bias analyses were quantified and assessed. Threshold measurements, TRV, and blind spot location accuracy were compared with those of the HFA. Main Outcome Measures: Pointwise threshold sensitivity, sectoral mean sensitivity (MS), mean deviation (MD), pattern standard deviation (PSD), TRV, blind spot location, average test time were computed, and data were correlated. Results: The mean time required to perform a field test with the AVA was 7.08 ± 1.55 minutes and with HFA was 6.26 ± 0.54 minutes (P = 0.228). The MS difference between AVA and HFA was –2.2 ± 2.3 dB in healthy participants (P < 0.001) and –2.6 ± 3.5 dB in participants with glaucoma (P < 0.001). The correlation coefficients for pointwise threshold values were moderately to strongly correlated for both the devices (r = 0.68–0.89). For MS, the overall ICC value was 0.893 (P < 0.001) with MB of 2.48 dB and a limits of agreement (LOA) of 10.90 (range, 7.93 to –2.97). For TRV, response variability decreased with an increase in sensitivity and increased with eccentricity. Blind spot location was accurate, and global indices of testing methods correlated well. Conclusions: The AVA effectively captures threshold values for each point in the visual field. Adequate functional correlation suggests substantial equivalence between the AVA (ESA) and HFA (SITA Standard), implying that AVA may allow accurate assessment of visual field.
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- 2021
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10. When the savior becomes a demon: Silicon oil synechia-induced glaucoma
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Amar Agarwal, Priya Narang, and Rhea Narang
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angle closure glaucoma ,glaucoma ,retinal detachment ,silicon oil ,pas ,peripheral anterior synechias ,pupilloplasty ,Ophthalmology ,RE1-994 - Abstract
Background: Silicon oil is an important adjunct for achieving internal tamponade in the treatment of retinal detachment. Silicone oil tamponade often leads to narrowing of the angle and development of adhesions between the iris and anterior chamber angle structures, with consequential elevation of the intraocular pressure. The video showcases the management of these challenging scenarios. Purpose: To highlight the management of early synechial closures due to silicon oil tamponade. Synopsis: The video highlights the management of early synechial closure following silicon oil tamponade. Surgical pupilloplasty has been demonstrated to break the peripheral anterior synechias on intraoperative gonioscopy as well as on anterior segment optical coherence tomography (AS-OCT). Performing pupilloplasty in the early phase of development of peripheral anterior synechias (PAS) helps to break the existing synechias and prevent angle closure and sequential deterioration of vision. Highlights: Surgical pupilloplasty helps to relieve the post silicon oil-induced secondary angle closure glaucoma by breaking the peripheral anterior synechias and significantly opening the anterior chamber angles. Online Video Link: https://youtu.be/xe2NGlhPBF4
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- 2022
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11. Epiretinal membrane profile on spectral domain optical coherence tomography in patients with uveitis
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Puja Maitra, Dhivya Ashok Kumar, and Amar Agarwal
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Epiretinal membrane ,epiretinal membrane changes in spectral domain OCT ,optical coherence tomography ,uveitis ,Ophthalmology ,RE1-994 - Abstract
Purpose: To study the epiretinal membrane (ERM) profile on the spectral-domain optical coherence tomography (SDOCT) in eyes with uveitis. Methods: In this prospective observational study, macula of uveitic eyes were evaluated by SDOCT (Cirrus, model 5000) for ERM. ERM was quantified (in microns) and were followed up along with the best-corrected visual acuity (BCVA) and treatment profile for 1 year. ERM morphology (focal, global, or mixed) and characteristics (thickness at fovea, maximum thickness, and location of maximum thickness in relation to fovea) were documented. Changes in altered foveal contour, cystoid macular edema (CME), and central foveal thickness were also noted. BCVA was noted when the inflammation subsided and it was correlated to specific ERM characteristics. SDOCT characteristics were compared in three treatment groups (no oral steroids, oral steroids with, and without immunomodulators). Results: Thirty-four eyes of 25 patients were evaluated. Mean logMAR BCVA decreased from 0.25 to 0.35 (P = 0.005). Foveal involvement with ERM (P = 0.011), lost foveal contour (P = 0.043), and ellipsoid layer disruption (P = 0.017) were associated significantly with reduced BCVA. Focal attachment of ERM was more commonly associated with CME (P = 0.03). Median ERM thickness showed significant increase (P < 0.001). Significant ERM progression from parafoveal to foveal (P = 0.02), significant progression of the thickest area of ERM closer to fovea (P = 0.0006) indicated a strong tendency of foveal involvement and this was correlated with worse BCVA (P = 0.009, r = −0.44) Oral steroids/immunomodulators showed no significant benefit on ERM progression. Conclusion: ERM progression in uveitis has a tendency to involve the fovea and is associated with significant vision loss, particularly in foveal ERM, focal attachment, and IS-OS disruption. Oral steroids and immunomodulators have no role in halting progression.
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- 2019
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12. Iris and knot configuration after Single Pass Four Throw (SFT) pupilloplasty as imaged by the spectral-domain optical coherence tomography
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Dhivya Ashok Kumar, Amar Agarwal, Radhika Chandrasekar, and Nagaraj Jaganathasamy
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Optical coherence tomography ,pupilloplasty ,single pass four throw pupilloplasty ,Ophthalmology ,RE1-994 - Abstract
Purpose: To analyze the morphological changes in the iris-knot complex configuration using spectral-domain optical coherence tomography (SD-OCT) following the single pass four throw (SFT) pupilloplasty. Methods: In this retrospective case series, eyes with SFT pupilloplasty were examined by SD-OCT (Optovue). Iris morphology compared to the normal iris, presence of specific patterns (single hump, double humps, peaks and valleys, tethering), prolene suture, knot complex (length and orientation), and intraocular lens (IOL) vault were evaluated. Results: Overall, 41 knots of 26 patients with a mean time duration of 3.1 ± 2 months from surgery were analyzed. Iris configurations seen were single hump (n = 28, 63.8%), double humps (n = 7, 17%), loop (n = 2, 4.8%), flat (n = 3, 7.3%), and mulberry (n = 1, 2.4%). The mean length and the height of the knot complex was 784.1 ± 433.7 μm and 317.7 ± 110.4 μm, respectively. Knot positions were at 3 clock hours in 9 eyes (21.9%), 9 in 8 eyes (19.5%), and others in 24 eyes (58.5%). Cut end of the prolene suture was detectable in 26 eyes (63.4%) as hyper-reflective line, and the mean cut length was 465.8 ± 321.1 μm. The suture was predominantly vertically oriented (80.6%) to the iris with a mean distance of 3.6 ± 0.3 mm (2.6–4 mm) away from corneal endothelium. The mean distance from the knot complex and the IOL was 289.2 ± 146 μm and the mean anterior chamber depth was 4.1 ± 0.1 mm. Conclusion: A significant change in iris configuration was noted after SFT pupilloplasty, and vertically oriented retained prolene suture was predominant with good endothelial vault.
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- 2019
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13. Uveitis and deficient lens capsules: Effect of glued intraocular lens on the visual outcome and the reactivation of inflammation
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Dhivya Ashok Kumar, Amar Agarwal, and Wasim Raja Kader Ali
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Glued IOL and uveitis ,glued IOL in post uveitic eyes ,reactivation of uveitis ,Ophthalmology ,RE1-994 - Abstract
Purpose: To evaluate the visual outcome and complication profile after glued intraocular lens (IOL) in post uveitic eyes. Methods: Patients with history of uveitis who had glued IOL with 3 months antecedent quiet anterior chamber (AC) were included in this prospective observational case series. Visual acuity, slit-lamp examination, fundus evaluation, optical coherence tomography, intraocular pressure, specular count and AC inflammation were analyzed before and after glued IOL procedure. Glued IOL eyes were also compared with their fellow normal capsular bag IOL. Results: Overall 17 eyes (50.7 ± 16.1 years) were analyzed. It included 41.8%, 23.5%, and 35.29% anterior, posterior, and pan uveitis, respectively. The etiologies were tuberculosis (23.53%), toxoplasmosis (11.77%), Fuch's heterochromic cyclitis (5.88%), HLA B27 (11.77%), psoriatic arthritis (5.88%), Rheumatoid arthritis (5.8%), sarcoidosis (11.77%), herpetic kerato-uveitis (5.88%), and idiopathic (17.65%). Cataractous subluxated lens (35.3%), aphakia (23.5%), decentered IOL (23.5%) and intraoperative capsular rupture (17.6%) were the surgical indications. A significant improvement in the mean uncorrected and best corrected visual acuity (P < 0.001) was recorded. The complications were IOL pigment dispersion (47%), macular edema (41%), and epiretinal membrane (24%). There was significant rise in AC reaction on day 1 (P < 0.001) and normal AC was attained by 88.2% eyes at 6 months. AC inflammation reactivation was noted in 11.7% of eyes. Though inflammatory reactivation was similar to the normal IOL, macular edema was higher in glued IOL. Conclusion: Glued IOL can cause inflammation in uveitis eyes which can be managed medically with minimal complications.
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- 2019
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14. Clinical characteristics and treatment outcomes of angioid streak associated choroidal neovascular membrane (AS-CNV): a Zambian case series
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Kshitiz Kumar, Santosh Balasubramaniam, and Amar Agarwal
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angioid streak ,choroidal neovascular membrane ,comet-tail lesion ,ranibizumab ,aflibercept ,Medicine - Abstract
This case series illustrates clinical features and treatment outcomes of angioid streak associated CNV (AS-CNV) in 3 consecutive patients. Mean age of patients was 43.2 years with one female patient. Bilateral CNV was present in one patient. Comet-tail lesions were present in all cases. No underlying systemic association was found in any of the patients. All patients were treated with 3 loading doses of anti-VEGF injections (ranibizuab in two and aflibercept was used in one case). Subretinal fluid resolved in all cases with no recurrence of CNV activity at mean follow-up of 10.75 months. AS-CNV in Zambian eyes responds favourably to anti-VEGF injections.
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- 2020
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15. Phacoemulsification with single-pass four-throw pupilloplasty and pre-Descemet's endothelial keratoplasty for management of cosmetic iris implant complication
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Priya Narang, Keiki Mehta, and Amar Agarwal
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Cosmetic iris implants ,iris implant complications ,PDEK ,phacoemulsification ,pre-Descemet's endothelial keratoplasty ,pupilloplasty ,SFT ,single-pass four throw ,Ophthalmology ,RE1-994 - Abstract
Placement of an anterior chamber iris implant for cosmetic reasons has been associated with development of various complications. Even after the implant has been explanted from the eye, it leaves a trail of after effects that necessitate surgical management. We describe a technique that comprises of performing phacoemulsification with single-pass four-throw pupilloplasty and a pre-Descemet's endothelial keratoplasty procedure for this eye with cosmetic iris implant complication.
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- 2018
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16. Extended focal length intraocular lens implantation in posttraumatic posterior capsular rupture
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Preethi Srinivasaraghavan, Dhivya Ashok Kumar, Amar Agarwal, and Akshya Parthasarathy
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Extended depth of focus ,extended focal length intraocular lens ,posterior capsule rupture ,traumatic posterior capsule tear ,Ophthalmology ,RE1-994 - Abstract
We present a case of posterior capsular defect with traumatic cataract after blunt trauma in which an extended focal length intraocular lens (IOL) was implanted in the bag after conventional phacoemulsification and anterior vitrectomy. Anterior segment optical coherence tomography performed preoperatively aided in the confirmation and documentation of the capsular integrity. Intraoperative trocar anterior chamber (AC) maintainer allowed AC maintenance without further complications. IOL was well centered postoperatively at 6 months, and the unaided visual acuity was 20/20 for distance and N8 for near. The report showed that an extended depth of focus IOL can be placed in eyes with ruptured posterior capsule for good visual outcome in posttraumatic young eyes and it may not be considered as a relative contraindication for it.
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- 2018
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17. 'Mouse Sign' on optical coherence tomography of detached endothelial graft indicates graft inversion
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Dhivya Ashok Kumar, Shana Sood, and Amar Agarwal
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Graft Detachment ,Mouse Configuration in Endothelial Graft ,Mouse Sign in OCT ,Mouse Sign in PDEK ,Mouse Sign ,OCT Configuration of Inverted Graft ,Pre-Descemet's Endothelial Keratoplasty ,Ophthalmology ,RE1-994 - Abstract
Purpose: To report the mouse-like configuration of detached endothelial keratoplasty graft observed on optical coherence tomographic imaging after pre-Descemet's endothelial keratoplasty (PDEK). Case Report: Three eyes of 3 patients who underwent PDEK and had graft detachment in the initial postoperative period of
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- 2018
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18. Single-pass four-throw pupilloplasty for angle-closure glaucoma
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Priya Narang, Amar Agarwal, and Dhivya A Kumar
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Angle-closure glaucoma ,peripheral anterior synechia ,pupilloplasty ,single-pass 4-throw ,SFT ,Ophthalmology ,RE1-994 - Abstract
Angle-closure glaucoma is characterized by appositional or synechial closure of the anterior chamber angle with glaucomatous field defects that may or may not be associated with a pupillary block. Surgical pupilloplasty with single-pass four-throw technique helps to alleviate the appositional closure along with the breakage of peripheral anterior synechia, thereby increasing the aqueous outflow and decreasing intraocular pressure.
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- 2018
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19. Modified Faden operation –A new surgical technique
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Manjula Jayakumar, Suganya Vel, and Amar Agarwal
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5-0 double-armed polyester suture ,conventional Faden operation ,modified Faden operation ,recession ,small angle esotropia ,Ophthalmology ,RE1-994 - Abstract
Faden operation was first described in 1912. It weakens the muscle in its field of action without much slackening and alteration in the primary position. When combined with recession the weakening effect is more. It is a useful surgery in esotropia with high accommodative convergence, nystagmus blockage syndrome, dissociated vertical deviation, Duane's retraction syndrome with up or downshoots, and in sixth nerve paresis, where it is performed on the contralateral normal yoke muscle to increase the field of binocular vision. The conventional procedure is cumbersome due to small working space, entanglement of sutures, and posterior location of Faden site which is not easily accessible. We have modified the Faden operation by using a single 5-0 double-armed polyester suture, which is much easier and simpler to perform, and have done it in a series of small angle esotropias combined with recession. This paper demonstrates the surgical technique so that this surgery can be performed with ease by more surgeons.
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- 2019
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20. Pre-Descemet's endothelial keratoplasty
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Priya Narang and Amar Agarwal
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Descemet's membrane endothelial keratoplasty ,double-infusion cannula technique ,endothelial keratoplasty ,glued intraocular lens ,infant donor ,pre-Descemet's endothelial keratoplasty ,scarred cornea ,trocar anterior chamber maintainer ,young donor ,Ophthalmology ,RE1-994 - Abstract
Endothelial keratoplasty (EK) has supplanted the penetrating keratoplasty procedure for corneal endothelial disorders. A review of literature on pre-descemet's EK, that is, a latest iterant in EK is described along with our experiences.
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- 2017
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21. Glued intrascleral haptic fixation of an intraocular lens
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Priya Narang and Amar Agarwal
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Double infusion cannula technique ,fibrin glue ,glued IOL ,IOL scaffold ,handshake technique ,no-assistant technique ,pre-Descemet's endothelial keratoplasty ,SFT ,triumvirate ,T-ACM ,Ophthalmology ,RE1-994 - Abstract
Glued intrascleral haptic fixation of an intraocular lens (glued IOL) has evolved as a technique with various modifications that are adopted and practiced by several surgeons. With adequate and appropriate haptic tuck, glued IOL imparts a stable IOL fixation and is a secured method of secondary IOL placement with no pseudophacodonesis.
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- 2017
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22. Clinical outcomes in traumatic pseudophacocele: A rare clinical entity
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Priya Narang and Amar Agarwal
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Blunt trauma ,glued intraocular lens ,hyphema ,intraocular lens dislocation ,pars plana vitrectomy ,pseudophacocele ,pupilloplasty ,single pass 4-throw technique ,trauma ,vitreous hemorrhage ,Ophthalmology ,RE1-994 - Abstract
Purpose: The purpose of this study is to evaluate the clinical outcomes in patients with traumatic pseudophacocele. Methods: In this retrospective, interventional case series, scleral wound repair with pars plana vitrectomy and glued intrascleral fixation of an intraocular lens (glued IOL) was performed in 5 eyes of 5 patients. Pupilloplasty was performed in 3 cases whereas aniridia glued IOL fixation was done in 1 case that had total avulsion and loss of iris tissue. The main outcome measures were best-corrected visual acuity (BCVA), intraoperative and postoperative complications during the entire follow-up period. Results: The preoperative vision ranged from hand movement to perception of light in all the patients. The mean postoperative BCVA was 0.42 ± 0.21 Snellen's decimal equivalent (SDE) at final follow-up. Postoperatively, all the cases retained good visual acuity with case 1 and case 2 reporting 0.5 SDE, case 3 had 0.33 SDE, case 5 had 0.67 SDE whereas case 4 had a final visual acuity limited to 0.1 SDE due to associated corneal opacity. The mean follow-up period was 20.2 ± 11.7 months (range from 9 months to 36 months). The IOL was well centered, all the wounds were well apposed and the mean postoperative intraocular pressure was 14.6 ± 1.95 mm Hg. No complications were reported in the entire follow-up period. Conclusion: The clinical outcomes of management of pseudophacocele were encouraging with retention of reasonably good visual potential in all cases.
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- 2017
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23. A rare case of symptomatic ocular pyogenic granuloma in pregnancy
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Dhivya Ashok Kumar, Heba Thajudeen, and Amar Agarwal
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lobular capillary hemangioma ,pregnancy ,pyogenic granuloma ,Ophthalmology ,RE1-994 - Published
- 2020
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24. Spatula scaffold: An iris-sparing technique for lensectomy
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Priya Narang and Amar Agarwal
- Subjects
Ectopia lentis ,lens subluxation ,lensectomy ,scaffold ,spatula scaffold ,vitrectomy ,Ophthalmology ,RE1-994 - Abstract
Lensectomy with vitrectomy is often performed for crystalline lenticular subluxation. We report a new technique and a practical approach that involves the placement of a spatula beneath the iris tissue that facilitates retroiridial removal of subluxated lens and acts as a scaffold by protecting the iris tissue from being accidentally trapped into the vitrectomy cutter port. Our technique facilitates management of the lens and vitreous without any trauma to the iris and secondarily obviates the need to perform an iris repair procedure that may arise due to iatrogenic reasons.
- Published
- 2017
- Full Text
- View/download PDF
25. Giant eyelid eccrine hidrocystoma-induced progressive ptosis in childhood
- Author
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Dhivya Ashok Kumar and Amar Agarwal
- Subjects
Childhood acquired ptosis ,eccrine hidrocystoma ,giant hidrocystoma ,progressive ptosis ,Ophthalmology ,RE1-994 - Abstract
An upper lid eccrine hidrocystoma presenting as early childhood progressive ptosis is very rare. We present a 9-year-old female child with droopy right upper lid since birth and progressive increase in symptoms. She had right upper lid ptosis (marginal reflex distance 1 of −1 mm) with fair levator function (8 mm) and abnormal cystic change on the conjunctival side. Computerized tomography imaging delineated the well-defined cystic lesion with homogeneous cavity with no contrast enhancement. Following the cyst excision, a giant eccrine hidrocystoma measuring 25 mm × 15 mm was removed, the largest reported in pediatric eyes. The case demonstrates the possibility of giant lid eccrine hidrocystomas presenting as progressive ptosis at a pediatric age and the need for early surgical intervention to prevent amblyopia.
- Published
- 2017
- Full Text
- View/download PDF
26. Predescemetocele: A distinct clinical entity
- Author
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Priya Narang, Amar Agarwal, and Dhivya Ashok Kumar
- Subjects
Deep anterior lamellar keratoplasty ,descemetocele ,penetrating keratoplasty ,pre-Descemet's endothelial keratoplasty ,pre-Descemet's layer ,predescemetocele ,Ophthalmology ,RE1-994 - Abstract
The case report incorporates a Fourier-domain optical coherence tomography (OCT) examination for demonstration of the existence of pre-Descemet's layer (PDL; Dua's layer) overlying a descemetocele and demonstrates predescemetocele as a separate clinical entity. The prospective analysis was done in two cases that had descemetocele, and OCT demonstrated the presence of PDL over an unruptured descemetocele that offers resilience and can be treated with an elective deep anterior lamellar keratoplasty or a penetrating keratoplasty. A descemetocele, when covered with PDL, should be correctly designated as a predescemetocele. Loss of PDL leads to baring of Descemet's membrane that eventually ruptures.
- Published
- 2017
- Full Text
- View/download PDF
27. Anterior chamber migration of intravitreal dexamethasone implant in glued intraocular lens
- Author
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Dhivya Ashok Kumar, Atul Dhawan, Soumya Narayanan, and Amar Agarwal
- Subjects
Dexamethasone implant migration ,glued intraocular lens ,ozurdex implant ,Ophthalmology ,RE1-994 - Published
- 2019
- Full Text
- View/download PDF
28. Clinical outcomes of pars plicata anterior vitrectomy: 2-year results
- Author
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Priya Narang and Amar Agarwal
- Subjects
Anterior vitrectomy ,pars plicata ,posterior capsule rupture ,vitreous prolapse ,Ophthalmology ,RE1-994 - Abstract
Purpose: To demonstrate the safety and outcome of a surgical approach that uses pars plicata site for anterior vitrectomy during phacoemulsification procedure complicated by posterior capsule rupture and residual cortical matter. Design: Single center, retrospective, interventional, noncomparative study. Materials and Methods: Medical records of a consecutive series of 35 eyes of 35 patients who underwent pars plicata anterior vitrectomy (PPAV) were reviewed. The main outcome measures were corrected and uncorrected distance visual acuity (CDVA, UDVA), early and late postoperative complications and intraocular pressure (IOP). Ultrasound biomicroscopic (UBM) evaluation of sclerotomy site and spectral domain optical coherence tomography analysis for central macular thickness (CMT) was performed. The final visual outcome at 2 years was evaluated. Results: At 2 years follow-up, the mean postoperative UDVA (logarithm of the minimum angle of resolution [logMAR]) and CDVA (logMAR) was 0.49 ± 0.26 and 0.19 ± 0.14, respectively. There was no significant change in the IOP (P = 0.061) and the mean CMT at 2 years was 192.5 ± 5.54 mm. The postoperative UBM image of the sclerotomy site at 8 weeks demonstrated a clear wound without any vitreous adhesion or incarceration. Intraoperative hyphema was seen in 1 (2.8%) case and postoperative uveitis was seen in 2 (5.7%) cases, which resolved with medications. No case of an iatrogenic retinal break or retinal detachment was reported. Conclusions: PPAV enables a closed chamber approach, allows thorough cleanup of vitreous in the pupillary plane and anterior chamber and affords better access to the subincisional and retropupillary cortical remnant with a significant visual outcome and an acceptable complication rate.
- Published
- 2015
- Full Text
- View/download PDF
29. The 'correct shake' for 'handshake' in glued intrascleral fixation of intraocular lens
- Author
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Priya Narang and Amar Agarwal
- Subjects
Glued intraocular lens ,handshake technique ,haptic externalization ,vertical glued intraocular lens ,Ophthalmology ,RE1-994 - Abstract
We hereby describe the correct method to perform a "handshake technique" and easy transfer of haptics from one hand to another for glued intrascleral fixation of an intraocular lens (glued IOL). The procedure was implemented in 57 cases that necessitated the application of performing a glued IOL procedure and it resulted in an appropriate and easy externalization of haptic in all the cases. The surgeons′ positioning with reference to the scleral flap is an essential component and the surgeon should always be positioned perpendicular to the plane of scleral flaps and the plane of haptic maneuver. The surgeons who intend to perform glued IOL should adopt this technical point.
- Published
- 2016
- Full Text
- View/download PDF
30. Stab Incision Glaucoma Surgery: A Modified Guarded Filtration Procedure for Primary Open Angle Glaucoma
- Author
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Soosan Jacob, Michele Figus, Dhivya Ashok Kumar, Ashvin Agarwal, Amar Agarwal, and Saijimol Areeckal Incy
- Subjects
Ophthalmology ,RE1-994 - Abstract
Purpose. To describe a modified guarded filtration surgery, stab incision glaucoma surgery (SIGS), for primary open angle glaucoma (POAG). Methods. This prospective, interventional case series included patients with POAG (IOP ≥21 mmHg with glaucomatous visual field defects). After sliding superior conjunctiva down over limbus, 2.8 mm bevel-up keratome was used to create conjunctival entry and superficial corneoscleral tunnel in a single step starting 1.5 mm behind limbus. Lamellar corneoscleral tunnel was carefully dissected 0.5–1 mm into cornea and anterior chamber (AC) was entered. Kelly Descemet’s punch (1 mm) was slid along the tunnel into AC to punch internal lip of the tunnel, thereby compromising it. Patency of ostium was assessed by injecting fluid in AC and visualizing leakage from tunnel. Conjunctival incision alone was sutured. Results. Mean preoperative IOP was 27.41±5.54 mmHg and mean postoperative IOP was 16.47±4.81 mmHg (n=17). Mean reduction in IOP was 38.81±16.55%. There was significant reduction of IOP (p
- Published
- 2016
- Full Text
- View/download PDF
31. Video Atlas of Anterior Segment Repair and Reconstruction: Managing Challenges in Cornea, Glaucoma, and Lens Surgery
- Author
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Amar Agarwal, Priya Narang and Amar Agarwal, Priya Narang
- Published
- 2019
32. Use of magnetic fabrics and X-ray diffraction to reveal low strains in experimentally deformed Maggia gneiss
- Author
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Sachin Kumar, Amar Agarwal, Auriol S. P. Rae, Agnes Kontny, and Michael H. Poelchau
- Subjects
General Earth and Planetary Sciences - Published
- 2023
33. Systematic reorientation of diamagnetic fabrics of Taunus quartzite due to experimental impact cratering
- Author
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Sonal Tiwari, Amar Agarwal, Thomas Kenkmann, and Michael H. Poelchau
- Abstract
Systematic reorientation of diamagnetic fabrics of Taunus quartzite due to experimental impact cratering Sonal Tiwari1, Amar Agarwal1, Thomas Kenkmann2, Michael H. Poelchau21Department of Earth Sciences, Indian Institute of Technology-Kanpur, Kanpur – 208016, India.2Geology, University of Freiburg, 79104 Freiburg, GermanyCorresponding author´s email: sonaljp20@iitk.ac.inAbstractPara- and ferromagnetic fabrics are known to provide essential clues for understanding impact cratering processes. However, research on the effects of shock waves on diamagnetic fabrics is lacking. We, therefore, conducted a hypervelocity impact experiment on a block of diamagnetic Taunus quartzite and studied the changes in diamagnetic fabrics. Taunus quartzite was formed by a low-grade Variscan metamorphism that overprinted a 405 Ma old sandstone. It consists of c. 91 vol % quartz and a fine-grained, greenish phyllosilicate-bearing matrix (c. 8 vol %), along with small amounts of rutile, chromite, zircon, monazite, and iron oxides.The experiment was carried out on a 20 cm Taunus quartzite cube with a two-stage light-gas gun of the Fraunhofer Ernst-Mach Institute for High-Speed Dynamics (EMI) in Freiburg (EMI), Germany. The gun has a 8.5 mm calibre launch tube. The 0.3690 g basalt sphere projectile was accelerated to 5.457 kms-1, with a target chamber pressure of 1.2 mbar. The projectile diameter (dp) was 6.18 mm. Later, 14 mm-diameter nonmagnetic diamond bits were used to drill oriented cylindrical cores from unshocked and shocked Taunus quartzite blocks. The AMS of the unshocked and shocked specimens was determined at room temperature in KLY-4S Kappabridge (AGICO). Following the AMS measurements, the cylindrical specimens were cut to make thin sections, which were studied under a Leica DM4 scanning optical microscope.Hypidiomorphic grain texture, serrated grain boundary, grain boundary migration, ataxial veins, Boehm lamellae, and recrystallized quartz represent the natural microscopic features. Impact-induced microstructures include trans- and intragranular microfractures. Our AMS results demonstrate that in the crater subsurface, the reorientation of the diamagnetic fabrics is concentrated in a zone of ~4 projectile diameters (25 mm) width directly below the point of impact. Higher reorientation in this zone indicates the concentration of damage. The damage is concentrated directly below the point of impact. Another important observation is that weak shock waves have caused an increase in the bulk susceptibility. These results, thus, show that the changes in diamagnetic fabrics can be used as a proxy for plastic deformation caused by shock waves at low peak pressures.Figure. The images show the specimens' position (black dots), the point source (brown dot), the impact crater (brown arc), and the variation in the orientation of k3.
- Published
- 2023
34. Essentials of OCT in Ocular Disease
- Author
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Amar Agarwal, Dhivya Ashok Kumar, Amar Agarwal, Dhivya Ashok Kumar and Amar Agarwal, Dhivya Ashok Kumar, Amar Agarwal, Dhivya Ashok Kumar
- Published
- 2015
35. Nature inspired synthesis of magnetite nanoparticle aggregates from natural berthierine
- Author
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Luis Manuel, Alva-Valdivia, primary, Amar, Agarwal, additional, Jaime, Urrutia-Fucugauchi, additional, and Arnaldo, Hernández-Cardona, additional
- Published
- 2023
- Full Text
- View/download PDF
36. Endothelial Keratoplasty: Mastering DSEK, DMEK, and PDEK
- Author
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Amar Agarwal, Terry Kim and Amar Agarwal, Terry Kim
- Published
- 2016
37. On the emplacement of the impact melt breccia at the Dhala Impact structure, India
- Author
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Gaurav Joshi, Pradyut Phukon, Amar Agarwal, and Arun Kumar Ojha
- Published
- 2022
38. Thermomechanical characterization of two Jalore granites with different grain sizes for India’s HLW disposal
- Author
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Pradeep Kumar Gautam, Suraj Pratap Singh, Amar Agarwal, and Trilok Nath Singh
- Subjects
Geology ,Geotechnical Engineering and Engineering Geology - Published
- 2022
39. The effect of shock waves on diamagnetic fabrics
- Author
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Sonal Tiwari, Amar Agarwal, Thomas Kenkmann, and Michael H. Poelchau
- Published
- 2022
40. Twofold technique for iridodialysis repair
- Author
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Amar Agarwal, Priya Narang, and Rhea Narang
- Subjects
Ophthalmology ,Iris Diseases ,Sutures ,Pupil Disorders ,Suture Techniques ,Humans ,Iris - Abstract
Disinsertion of iris leads to debilitating sequelae like diplopia and glare. Hence, iridodialysis repair is essential to optimize the visual quality. Iris base repair often leads to corectopia that necessitates an additional procedure to optimize the pupil shape and size. Twofold technique helps to achieve both the aspects.To highlight the technique of twofold iridodialysis repair.The video highlights the method of twofold iridodialysis repair, wherein nonappositional repair is followed by single-pass four-throw (SFT) pupilloplasty that allows adequate closure of varied degrees of iridodialysis along with centration of eccentric pupil.The twofold technique is a combination of nonappositional iris repair and SFT procedure. It can be clinically applied in all cases of iridodialysis with varied degrees of severity.https://youtu.be/OncBdz2UIBY.
- Published
- 2022
41. Pinhole pupilloplasty after previous radial keratotomy
- Author
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Dhivya Ashok Kumar, Ashvin Agarwal, Priya Narang, Soundari Sivagnanam, and Amar Agarwal
- Subjects
Image quality ,business.industry ,Computer science ,medicine.medical_treatment ,Pupilloplasty ,eye diseases ,Sensory Systems ,03 medical and health sciences ,Ophthalmology ,Radial keratotomy ,0302 clinical medicine ,medicine.anatomical_structure ,Optics ,Cornea ,030221 ophthalmology & optometry ,medicine ,Surgery ,Pinhole (optics) ,business ,030217 neurology & neurosurgery - Abstract
The multiple radial stromal deep corneal incisions placed in radial keratotomy (RK) lead to higher-order aberrations and pose a surgical challenge to performing any further corrective procedure on the cornea because of fear of inducing an incisional dehiscence. A method to perform pinhole pupilloplasty (PPP) in the setting of previous RK is presented. Application of pinhole optics by performing PPP leads to significant improvement in image quality and helps to optimize visual potential in post-RK cases.
- Published
- 2021
42. Decompensated cornea with epithelial and stromal edema
- Author
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Rupert Menapace, Thomas Neuhann, Gerald Schmidinger, Ehud Assia, Jorge Alió, Priya Narang, Amar Agarwal, and Peter Szurman
- Subjects
Adult ,Lenses, Intraocular ,Visual Acuity ,Sensory Systems ,Corneal Diseases ,Cornea ,Ophthalmology ,Iris Diseases ,Lens Implantation, Intraocular ,Edema ,Humans ,Surgery ,Female ,Aged - Abstract
A 66-year-old patient underwent surgery for congenital cataract in both eyes in her first year of life without implantation of an intraocular lens (IOL). In 1994, at the age of 39 years, both eyes received secondary Kelman multiflex-style angle-fixated anterior chamber IOLs (AC IOLs). The surgeries were followed by retinal detachments in both eyes, in the left eye in the same year and in the right eye 4 years later, which were successfully repaired. The patient presented with a decompensated cornea with epithelial and stromal edema in the left eye. The AC IOL axis was oriented from 5- to 8-o'clock position with the haptic contacting the cornea. The distal portion of the inferior-nasal haptic was deeply buried and entrapped in a broad iridocorneal synechia extending between 6- and 8-o'clock positions. The synechia also caused adjacent pupillary distortion and pigment leaf eversion (Figure 1JOURNAL/jcrs/04.03/02158034-202205000-00021/figure1/v/2022-04-22T173532Z/r/image-tiff). The AC IOL in the right eye was well positioned, and the cornea was clear with an endothelial cell count (ECC) of 2160 cells/mm2 and central corneal thickness (CCT) of 650 μm. No ECC was obtainable in the left eye, and CCT was 775 μm (Figure 2JOURNAL/jcrs/04.03/02158034-202205000-00021/figure2/v/2022-04-22T173532Z/r/image-tiff). Visual acuity was 0.8 corrected in the right eye and hand motion in the left eye. Both eyes were normotonic. On optical coherence tomography (OCT) imaging, a broad iridocorneal synechia was visible with a canal corresponding to the deeply buried haptic end of the AC IOL (Figure 3JOURNAL/jcrs/04.03/02158034-202205000-00021/figure3/v/2022-04-22T173532Z/r/image-tiff). Abundant condensed cortical material (Soemmerring's ring) was found behind the iris and above the ciliary body. What would be your surgical options to rehabilitate the patient's left eye considering corneal decompensation caused by haptic contact of an angle-fixated AC IOL and capture of 1 haptic within an iridocorneal synechia extending along 2 clock hours?
- Published
- 2022
43. Asymmetric development of the Himalaya: quantitative evidence from strain analysis in Kimin-Ziro-Tamen area, Arunachal Lesser Himalaya, India
- Author
-
Priyambada Singh, Sushmita Singh, Gaurav Joshi, K. K. Agarwal, and Amar Agarwal
- Subjects
010504 meteorology & atmospheric sciences ,Syntaxis ,Geochemistry ,Deformation (meteorology) ,010502 geochemistry & geophysics ,01 natural sciences ,Plate tectonics ,Crenulation ,Shear (geology) ,Finite strain theory ,General Earth and Planetary Sciences ,Sedimentology ,Structural geology ,Geology ,0105 earth and related environmental sciences - Abstract
The eastern segment of the Himalaya makes a quarter of the mountain belt. While its plate tectonic setting is well understood, the intensity of deformation along the thrusts is not well constrained. This knowledge gap has restricted a quantitative comparison of deformation and crustal shortening in the Eastern Lesser Himalaya with the Central and Western Lesser Himalaya. In this study field evidence, together with microstructural investigations, and two-dimensional (2D) finite strain analysis are used to decipher the deformation pattern in the Kimin-Ziro-Tamen area of the Eastern Lesser Himalaya. Present investigations reveal that micro-to-outcrop-scale structures such as plastically deformed quartz grains, crenulation cleavages, S-C fabric, pull-apart grains, pinch-n-swell structures, boudins and faults confirm that the rocks have been subjected to ductile and brittle-ductile phases of deformation with a regional top-to-south shear sense. The 2D finite strain estimated here is comparable to that in other parts of Eastern Lesser Himalaya, such as the Sikkim and Bhutan Himalaya. However, the strain estimated here is higher than in the Central and Western Lesser Himalaya, such as in the Central Nepal Himalaya, Almora Crystalline Zone, the Garhwal Lesser Himalaya and the Hazara-Kashmir Syntaxis in Pakistan. This provides quantitative proofs of greater deformation and crustal shortening in the Eastern Lesser Himalaya than the Central and Western Himalaya, and of the asymmetric development of Himalaya.
- Published
- 2021
44. Color Atlas of Ophthalmology: The Quick-Reference Manual for Diagnosis and Treatment
- Author
-
Amar Agarwal, Soosan Jacob, Amar Agarwal, Soosan Jacob and Amar Agarwal, Soosan Jacob, Amar Agarwal, Soosan Jacob
- Published
- 2011
45. Pinhole Pupilloplasty for Higher Order Aberrations: Assessment of Visual Quality and Depth of Focus
- Author
-
Jack T. Holladay, Helen Gracy, Soundari Sivagnanam, Priya Narang, Amar Agarwal, and Dhivya Ashok Kumar
- Subjects
medicine.medical_specialty ,Visual acuity ,genetic structures ,Mesopic vision ,media_common.quotation_subject ,Visual Acuity ,Contrast Sensitivity ,03 medical and health sciences ,0302 clinical medicine ,Lens Implantation, Intraocular ,Ophthalmology ,medicine ,Humans ,Contrast (vision) ,Prospective Studies ,Dioptre ,Mathematics ,media_common ,Lenses, Intraocular ,Glare (vision) ,eye diseases ,Aberrations of the eye ,030221 ophthalmology & optometry ,Surgery ,Spatial frequency ,medicine.symptom ,030217 neurology & neurosurgery ,Photopic vision - Abstract
PURPOSE: To evaluate visual quality and depth of focus under photopic and mesopic light conditions of patients treated with pinhole pupilloplasty (PPP) for corneal higher order aberrations. METHODS: This was a prospective, noncomparative, interventional series and PPP was performed with a single-pass four-throw procedure in 14 eyes of 14 patients. After PPP, patients were analyzed with the Clinical Trial Suite machine (M & S Technologies, Inc) that offers a standardized method of recording visual quality. The luminance levels of 85 and 3 cd/m 2 were set for photopic and mesopic lighting conditions, respectively, and uncorrected and corrected distance visual acuity were recorded for distance (4 m), intermediate (66 cm), and near (44 cm). Low contrast acuity (LCA) at 10% and mesopic contrast sensitivity function (CSF) with glare on and off at four spatial frequencies of 1.5, 3, 6, and 12 cycles per degree (cpd) and defocus curve were assessed. RESULTS: Under photopic and mesopic conditions, a significant difference was observed postoperatively in uncorrected and corrected distance visual acuity for distance, intermediate, and near. The defocus curve demonstrated extended depth of focus that ranged from +1.50 to −2.50 diopters and LCA at 10% demonstrated significant improvement for all cases. For mesopic CSF, a significant improvement was noted at spatial frequencies of 3 and 6 cpd with glare on. With glare off, an improvement was seen at spatial frequencies of 1.5, 3, and 6 cpd, but not at 12 cpd. CONCLUSIONS: Early results demonstrate that PPP provides improved visual quality and extended depth of focus and can be a useful option in cases with higher order aberrations. [ J Refract Surg . 2020;36(12):812–819.]
- Published
- 2020
46. Stereographic Reconstruction of Impact Microstructures using Optical and Electron Microscopy
- Author
-
Boris Reznik, Deepak Srivastava, and Amar Agarwal
- Subjects
Microscope ,business.industry ,Scanning electron microscope ,Orientation (computer vision) ,Stereographic projection ,Geology ,010501 environmental sciences ,010502 geochemistry & geophysics ,Microstructure ,01 natural sciences ,law.invention ,Field emission microscopy ,Optics ,Optical microscope ,law ,Electron microscope ,business ,0105 earth and related environmental sciences - Abstract
This study reconstructs the pre-impact orientation of impact-generated µm-sized microstructures. The approach is illustrated using a sample from the basement dolerites of the Lockne impact structure, Sweden. Under the polarised light microscope, the microstructure appears as alternating augite-plagioclase wedges. The top-view of the microstructure is presented in the polished thin-section using light and scanning electron microscopy, while, the side-view is observed in focused-ionbeam trenches in a field emission scanning electron microscope. The top- and side view of the wedges are projected on a stereo net, which allows the determination of their 3D orientation. The wedges are thus found to have a dip of 08° towards 280°. The stereo net projections are then used to reconstruct the orientation of pre-impact boundary between augite-plagioclase, which had a dip of 15° towards 237°. This approach of combining light and electron microscopy with FIB trenching and projecting the data on a stereo net can be especially useful for reconstructing the pre-deformed state of impact-induced or tectonic µm-sized microstructures, which cannot be adequately analysed using a light microscope.
- Published
- 2020
47. Evidence for shock provides insight into the formation of the central elevated area in the Dhala impact structure, India
- Author
-
Satyendra Kumar, Gaurav Joshi, Amar Agarwal, and K. K. Agarwal
- Subjects
Geophysics ,Space and Planetary Science ,Shock (circulatory) ,medicine ,Mechanics ,Impact structure ,medicine.symptom ,Geology - Published
- 2020
48. Contact lens assisted corneal cross linking in thin ectatic corneas – A review
- Author
-
Soosan Jacob, Amar Agarwal, and Sanjana Srivatsa
- Subjects
Thin cornea ,genetic structures ,Corneal Pachymetry ,Special solution ,Contact Lenses ,Swine ,Ultraviolet Rays ,corneal allogenic intrastromal ring segments (CAIRS) ,Corneal Stroma ,Riboflavin ,Visual rehabilitation ,Review Article ,thin cornea ,Keratoconus ,Cornea ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Corneal shape ,medicine ,Animals ,Photosensitizing Agents ,business.industry ,contact lens assisted cross-linking (CACXL) ,Contact lens ,eye diseases ,Ophthalmology ,medicine.anatomical_structure ,Cross-Linking Reagents ,Photochemotherapy ,Lens (anatomy) ,030221 ophthalmology & optometry ,sense organs ,Collagen ,business ,030217 neurology & neurosurgery ,Biomedical engineering - Abstract
Contact lens-assisted corneal cross-linking (CACXL) was introduced by Jacob et al. in 2012 for treating thin keratoconic corneas using riboflavin soaked soft contact lens to artificially increase the functional corneal thickness. It is advantageous over other thin corneal cross-linking techniques as it works independent of swelling properties of the cornea, is an epi-off technique and does not require additional time, additional expensive equipments or special solutions. The only additional requirement as compared to all other techniques is a UV barrier-free soft contact lens (SoflensTM, B&L) which is easily available and inexpensive. Advantages include simplicity, easy adaptability, early visual rehabilitation, good visual outcomes, safety, and efficacy. Progression rates are acceptable and the need for re-treatment has been low. CACXL can help regularize corneal shape and may be used in isolation or synergistically with Intracorneal ring segments (ICRS) or Corneal allogenic intrastromal ring segments (CAIRS). It gives about 70% stiffening as compared to standard Dresden protocol CXL in less ideal porcine eye studies. Murine eye models that closely mimic thin corneas and show greater cross-linking effect as compared to porcine eyes may be a better model for evaluation of CACXL, however further studies are needed. Care should be taken in selecting the right kind of contact lens. Proper technique should be followed, especially by confirming thinnest functional pachymetry to be above 400 microns intra-operatively before application of UV-A. The sub-contact lens riboflavin film should be avoided as also an excessively thick supra-contact lens riboflavin film and too many re-applications.
- Published
- 2020
49. Trocar assisted nonappositional repair of iridodialysis
- Author
-
Amar Agarwal and Priya Narang
- Subjects
medicine.medical_specialty ,Sutures ,Iridodialysis ,Anterior Chamber ,business.industry ,Suture Techniques ,Lumen (anatomy) ,Pupilloplasty ,General Medicine ,Surgical Instruments ,medicine.disease ,Surgery ,03 medical and health sciences ,Ophthalmology ,0302 clinical medicine ,Iris Diseases ,Fluid infusion ,030221 ophthalmology & optometry ,Humans ,Medicine ,business ,030217 neurology & neurosurgery - Abstract
Purpose: To describe trocar-assisted method of Nonappositional repair of iridodialysis. Methods: The technique described involves placement of a 25 G trocar at the limbus wherein the lumen of the cannula works as a guide to introduce a double arm polypropylene suture attached to the long arm needle thereby preventing any accidental entrapment of corneal fibers into the needle. Results: The technique was performed in 7 cases and no entrapment of corneal tissue was observed while maneuvering the suture needle through paracentesis incision during an iridodialysis repair procedure. Anterior segment optical coherence tomography demonstrated closure of the limbal trocar wound at 1-week follow-up. No incidence of wound leak or Descemets membrane detachment was observed. Conclusion: The technique allows performing iridodialysis repair in technically challenging situations by directing the needle appropriately and preventing any undulating movement inside the anterior chamber. The trocar-assisted method serves as an effective method to perform non-appositional iridodialysis repair.
- Published
- 2020
50. Effect of monocular fixation in binocular field (MFBF) on amblyopia – a pilot study comparing it with patching
- Author
-
Helen Gracy Raju, Manjula Jayakumar, and Amar Agarwal
- Subjects
Male ,medicine.medical_specialty ,Time Factors ,Adolescent ,genetic structures ,Visual Acuity ,Pilot Projects ,Fixation, Ocular ,Amblyopia ,Cohort Studies ,03 medical and health sciences ,0302 clinical medicine ,Ophthalmology ,medicine ,Humans ,030212 general & internal medicine ,Child ,Vision, Binocular ,Monocular ,business.industry ,eye diseases ,Eyeglasses ,Treatment Outcome ,Stereopsis ,Child, Preschool ,Fixation (visual) ,030221 ophthalmology & optometry ,Female ,Sensory Deprivation ,Binocular field ,business - Abstract
54 children with anisometropic amblyopia of ages 4-15 years were included in the study - 24 children in the patching and 30 children in the MFBF group. The study ran for a period of 6 months with BCVA assessed at each visit of follow up.In the patching group, visual acuity (VA) gain was 0.37 ± 0.26 log Mar over the course of 6 months with continuous improvement in vision across the three time points (0.20 log mar in the first month, 0.11 log Mar from month1 to 3 and 0.06 log Mar from months 3 to 6).In the Amb I Net group, visual acuity gain was 0.54 ± 0.38 log Mar over the same course of time. A continuous improvement in vision was also noted, with gains of 0.16 in the first month, 0.19 from month 1 to 3 and 0.19 from month 3 to 6. The difference in log Mar gains in VA was not statistically significant between the treatment arms and the final VA was similar (0.25 log Mar for patching and 0.18 log Mar for Amb I net). However, clinically the patching group showed 3 log MAR lines, whereas the MFBF group showed 5 log MAR lines of vision improvement at the end of therapy.MFBF was not superior to patching as far as efficacy is concerned in anisometropic amblyopia. However, the combination of more game options to sustain interest, a shorter duration of therapy over the course of a week and software directed compliance monitoring system favors the Amb I Net system from both patient and parental perspective. Amb I Net also negated discomfort, social stigma, and parental monitoring needed with patching regimens. It can be considered as a good alternative to patching in reluctant/non - compliant children with anisometropic amblyopia. This is the first large cohort study based on this therapy.
- Published
- 2020
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