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R Marshall Ford, Yousuf M KhalifaDavid and Ilene Flaum Eye Institute, University of Rochester Medical Center, Rochester, NY, USAAbstract: A 64-year-old Caucasian male complaining of redness and tearing for 3 years in both eyes was referred for evaluation of cicatricial conjunctivitis. Ocular cicatricial pemphigoid was suspected and this diagnosis was confirmed through biopsy. The patient's condition showed moderate improvement following treatment with methotrexate and mycophenolate mofetil. The patient was later diagnosed with porphyria cutanea tarda and phlebotomy treatments were subsequently initiated. The patient's ocular symptoms improved further after he began receiving these phlebotomy treatments, and conventional treatment was discontinued. The authors hypothesize that circulating porphyrins activated by ultraviolet light could be the cause of the ocular cicatricial pemphigoid in this patient.Keywords: cicatricial conjunctivitis, phlebotomy treatments, circulating porphyrins, ultraviolet light

Majid Moshirfar1 Maylon Hsu1 Yousuf M Khalifa21Moran Eye Center, Salt Lake City, UT, 2Flaum Eye Institute, Rochester, NY, USAAbstract: The management of corneal ectasia is evolving, with intrastromal corneal ring segments playing an important role in delaying or eliminating the need for penetrating keratoplasty. This paper describes a modification in the implantation technique of intrastromal corneal ring segments that allows for coupling of the two segments with suture, affording more structural support.Keywords: intrastromal corneal ring segments, Intacs, keratonconus, corneal ectasia, keratoectasia

Purpose: To determine the efficacy of preoperative subconjunctival injection of mitomycin C a day before surgery in the management of recurrent pterygium.Materials and Methods: Randomized comparative case series. Fifty eyes with recurrent pterygium were randomly divided into two groups; the mitomycin injection group (25 eyes) and the mitomycin application group (25 eyes). The mitomycin injection group underwent preoperative subconjunctival injection of mitomycin C in low dose (0.1 ml of 0.15 mg/ml) a day before bare sclera pterygium excision surgery. The mitomycin application group underwent bare sclera pterygium excision with topical application of mitomycin C (same concentration).Results: At one year of follow-up, 24 of 25 eyes (96%) in the mitomycin injection group and 23 of 25 (92%) eyes in the mitomycin application group were free of recurrence. The difference was statistically insignificant. As regards postoperative complications, delayed epithelization (more than two weeks) occurred in two eyes (8%) in the mitomycin injection group and in one eye (4%) in the mitomycin application group. Scleral thinning was reported in one eye (4%) in the mitomycin application group which resolved within three weeks after surgery, no other serious postoperative complications were reported.Conclusion: Preoperative subconjunctival injection of mitomycin C in low dose (0.1 ml of 0.15 mg/ml) a day before pterygium surgery is a simple and effective modality for management of recurrent pterygium. It has the advantage of low recurrence and complications' rate. [ABSTRACT FROM AUTHOR]

Purpose: It remains unclear if fluid pressures used during cataract surgeries contribute to iatrogenic corneal endothelial cell (CEC) loss., Methods: A custom experimental platform was used to pressurize the anterior chamber of explanted porcine eyes to surgical fluid pressures of 60 mm Hg or 400 mm Hg for 5 minutes or 60 mm Hg for 45 minutes (n = 8 or 9 per group). The corneal endothelia were stained with a unique combination of nucleic acid viability dyes and were imaged using fluorescence microscopy without removing the cornea from the globe. The images were analyzed using custom code to quantify acute CEC loss as a percentage of CEC injury/death (PCI). The PCI values from the surgical pressure groups were compared to sham controls perfused to physiological pressures for each surgical duration. As a positive control, a group of eyes (n = 8) was perfused with deionized water to intentionally induce CEC injury/death., Results: No significant differences were observed in mean PCI values between any of the surgical fluid pressure groups and sham control groups, at either duration. The mean PCI of the positive control group was significantly different from all other groups, indicating that the method is able to detect CEC injury/death., Conclusions: Our results suggest that the magnitudes of fluid pressure used over the duration of a cataract surgery do not significantly contribute to acute iatrogenic CEC loss., Translational Relevance: Not only do the findings of this study answer a longstanding clinical question related to cataract surgery, but the platform introduced will facilitate testing how new cataract surgery devices and techniques affect CEC viability.

Background: Mortality from emergency left-sided colorectal surgery can be substantial due to acuteness of the presentation and the urgent need to operate in the setting of a limited preparation in a morbid patient., Objectives: Determine the 30-day postoperative outcomes and identify risk factors for complications and mortality following emergency colorectal operations., Design: Retrospective SETTINGS: Three tertiary hospitals in three countries., Patients and Methods: Factors that were studied included age, sex, ASA score, type and extent of the operation, and presence/absence of malignancy. Unadjusted 30-day patient outcomes examined were complications and mortality. Differences in proportions were assessed using the Pearson chi-square test while logistic regression analyses were carried out to evaluate the correlation between risk factors and outcomes., Main Outcome Measures: 30-day postoperative morbidity and mortality SAMPLE SIZE: 104 patients., Results: Among 104 patients, 70 (67.3%) were men, and 34 (32.7%) were women. The mean (SD) age was 57.2 (17.1) years. The most common indication for emergency colonic surgery was malignant obstruction in 33 (31.7%) patients. The postoperative complication rate was 24% (25/104), and the mortality rate was 12.5% (13/104) within 30 days of the operation. The ASA status ( P =.02), presence of malignancy ( P =.02), and the presence of complications ( P =.004) were significantly related to mortality in the multivariable logistic regression analysis., Conclusions: The 30-day mortality of emergency colorectal operations is greatly influenced by the presence of malignancy in the colon and physiological status at the time of the procedure., Limitations: The retrospective design and small sample size., Conflict of Interest: None.

High-voltage LiNi 0.5 Mn 1.5 O 4 (LNMO) spinel offers high specific energy and good rate capability with relatively low raw-material cost due to cobalt-free and manganese-rich chemical compositions. Also, increasing mass loading (mg/cm 2 ) by thickening cathodes has been one of the focused areas to greatly improve the energy density of lithium-ion batteries (LIBs) at the cell level. The LNMO cathode made with a polyvinylidene fluoride (PVdF) binder, however, suffers from an oxidative decomposition of liquid electrolytes and cathode delamination from a current collector. This problem is exacerbated with an increase in thickness. In this study, we developed a lithium polyacrylate (LiPAA)-sodium alginate (Na-Alg) composite binder series that offer positive multifunctions such as enhancing cathode adhesion and cohesion, improving cycle life, creating an effective passivating layer at the cathode-electrolyte interface (CEI), and lowering cell impedance. Comprehensive design of systematic experiments revealed a close chemo-mechano-electrochemical relationship in the thick high-voltage cathodes. Among the various binder compositions, the LiPAA (30 wt %)-Na-Alg (70 wt %) binder offered a strong adhesion property and positive multifunctions at the CEI layer, which consequently stabilized the solid-electrolyte interfacial (SEI) layer on the graphite anode and improved LIB performances. This novel composite binder will be applicable to various types of thick cathodes in future studies.

Purpose: To assess the phacoemulsification learning curve for ophthalmology residents using duration for each step., Setting: Single tertiary, training site hospital., Design: Cross-sectional study., Methods: Emory ophthalmology postgraduate year (PGY) 3 and PGY-4 residents operating at Grady Memorial Hospital between April 2017 and February 2018 were eligible to participate. Duration in seconds for each step of surgery was calculated for incisions, continuous curvilinear capsulorhexis (CCC), hydrodissection, nucleus disassembly, quadrant removal, cortical cleanup, intraocular lens insertion, and closure, and this outcome was analyzed as a function of different experience levels., Results: A total of 528 surgeries were included of 549 total surgeries recorded. 6 categories of experience levels were established as A to F, increasing by increments of 50. There was an overall downward trend across various steps across the 8 case categories, and several adjacent categories demonstrate statistically significant differences. The 3 most time-intensive steps early in training were nucleus disassembly (336.5 ± 16.5 seconds), quadrant removal (275.1 ± 18.0 seconds), and cortical cleanup (244.2 ± 24.6 seconds). There was a sustained drop in mean duration for all steps through at least category D, with most steps showing a drop through category F., Conclusions: There is a benefit to a higher caseload, well above the Accreditation Council for Graduate Medical Education-mandated 86 cases. Improvements in efficiency were observed after 250 cases, with nuclear disassembly and CCC demonstrating a significant decrease in operative time., Competing Interests: Disclosures: The authors have no funding, financial relationships, or conflicts of interest to disclose., (Copyright © 2021 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Background: Thyroidectomy is the surgical removal of all or part of the thyroid gland for non-neoplastic and neoplastic thyroid diseases. Major postoperative complications of thyroidectomy, including recurrent laryngeal nerve injury, hypocalcemia, and hypothyroidism, are not infrequent., Objective: Summarize the frequency of surgical complications of thyroidectomy., Design: Retrospective., Setting: Secondary health facility in southwestern Saudi Arabia., Patients and Methods: We collected data from the records of patients who were managed for thyroid diseases between December 2013 and December 2019., Main Outcome Measure: Complications following thyroidectomy., Sample Size: 339 patients, 280 (82.6%) females and 59 (17.4%) males., Results: We found 311 (91.7%) benign and 28 (8.3%) malignant thyroid disorders. Definitive management included 129 (38.1%) total thyroidectomies, 70 (20.6%) hemithyroidectomies, 10 (2.9%) subtotal thyroidectomies and 5 (1.5%) near-total thyroidectomies with 125 (36.9%) patients treated non-surgically. The overall complication rate was 11.3%. There were 4 (1.9%) patients with recurrent laryngeal nerve palsy, 16 (7.5%) patients with temporary hypoparathyroidism, 1 (0.5%) patient with paralysis of the external branch of the superior laryngeal nerve and 3 (1.4%) patients with wound hematoma., Conclusion: The rate of complications following thyroidectomy is still high. There is a need for emphasis on comprehensive measures to control the high rate of complications., Limitations: Retrospective design and no long-term follow up to monitor late complications., Conflict of Interest: None.

Background: This study assessed the impact of distance cataract surgical wet laboratory training on surgical competency of ophthalmology residents at a tertiary-level ophthalmic training center in Trujillo, Peru., Methods: Three five-week distance wet lab courses were administered through Cybersight, Orbis International's telemedicine platform. Weekly lectures and demonstrations addressed specific steps in phacoemulsification surgery. Each lecture had two accompanying wet lab assignments, which residents completed and recorded in their institution's wet lab and uploaded to Cybersight for grading. Competency was assessed through anonymous grading of pre- and post-training surgical simulation videos, masked as to which occurred before and after training, using a standardized competency rubric adapted from the Ophthalmology Surgical Competency Assessment Rubric (OSCAR, scale of 0-32). Day one best-corrected post-operative visual acuity (BVCA) was assessed in the operative eye on the initial consecutive 4-6 surgeries conducted by the residents as per the norms of their residency training. An anonymous post-training satisfaction survey was administered to trainees'., Results: In total, 21 ophthalmic residents participated in the courses, submitting a total of 210 surgical videos. Trainees' average competency score increased 6.95 points (95%CI [4.28, 9.62], SD = 5.01, p < 0.0001, two sample t-test) from 19.3 (95%CI [17.2, 21.5], SD = 4.04) to 26.3 (95%CI [24.2, 28.3], SD = 3.93). Visual acuity for 92% of post-training resident surgeries (n = 100) was ≥20/60, meeting the World Health Organization's criterion for good quality., Conclusions: Structured distance wet lab courses in phacoemulsification resulted in significantly improved cataract surgical skills. This model could be applicable to locations where there are obstacles to traditional in-person training, such as the current COVID-19 pandemic.

A rapid, cost effective, simple and reliable method was developed for the determination of Tianeptine (TIA) drug in bulk and in pharmaceutical formulation. The fluorescence of Vilazodone was measured in isopropanol at room temperature. The method was optimized by measuring the factors that may affect the fluorescence intensity such as: pH, diluting solvent, temperature and mixing time. The developed method was validated according to ICH guidelines in terms of accuracy, precision, linearity, range, LOD and LOQ. The concentration range was found to be linear in the range of 10-100 ng/ml. The LOD and LOQ values were found to be very small (1.86, 5.62 ng/mL. The % RSD and the % R were found within the acceptable range. Unlike the HPLC procedures, the proposed method for TIA determination has many advantages over the reported analytical methods represented in its rapidity, lower cost and environmental safety as the instrument is simple with low operating cost., Competing Interests: Declaration of Competing Interest Submission of this manuscript implies: that the work described has not been published before; the manuscript is being submitted exclusively for the Spectrochimica Acta part I Journal; it is not under consideration for publication anywhere else; and its publication has been approved by all the co-authors., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Purpose: To describe the ethical attitudes of corneal surgeons and eye bank leadership toward for-profit entities in corneal donation, processing, and distribution., Methods: Fifty postfellowship corneal surgeons practicing in the United States and 25 eye bank leaders (eg, eye bank directors, CEOs, or presidents) for the Eye Bank Association of America-accredited eye banks completed a 22-question interview, focusing on corneal donation industry changes, including the entry of for-profit institutions., Results: Most participants in both study groups agreed that they have concerns with the entry of for-profit businesses into eye banking (62% corneal surgeons, 68% eye bank leadership), although physicians partnered with a for-profit corneal processor were significantly more likely to have no concerns with the entry of for-profits into eye banking than corneal surgeons partnered with a nonprofit processor (P = 0.04). The most frequently identified concerns with the entry of for-profit businesses into corneal banking were the hypothetical loss of donor trust (56% corneal surgeons, 64% eye bank leadership, P = 0.04) and the potential exploitation of donor generosity (72% corneal surgeons, 60% eye bank leadership). Qualitative theme analysis suggests that both study groups may view increased research/innovation as a potential benefit (64% corneal surgeons, 66% eye bank leadership) of for-profits in eye banking., Conclusions: Key stakeholders in eye banking do hold relevant ethical beliefs toward recent industry changes, and these attitudes should be considered in the future creation of the ethical corneal donation policy. Further research is needed to assess the attitudes of potential donors and donor families.

Long-term thermal stability is one limiting factor that impedes the commercialization of the perovskite solar cell. Inspired by our prior results from machine learning, we discover that coating a thin layer of 4,4'-dibromotriphenylamine (DBTPA) on top of a CH 3 NH 3 PbI 3 layer can improve the stability of resultant solar cells. The passivated devices kept 96% of the original power conversion efficiency for 1000 h at 85 °C in a N 2 atmosphere without encapsulation. Near-ambient pressure X-ray photoelectron spectroscopy (XPS) was employed to investigate the evolution of the composition and evaluate thermal and moisture stability by in situ studies. A comparison between pristine MAPbI 3 films and DBTPA-treated films shows that the DBTPA treatment suppresses the escape of iodide and methylamine up to 150 °C under 5 mbar humidity. Furthermore, we have used attenuated total reflection Fourier transform infrared and XPS to probe the interactions between DBTPA and MAPbI 3 surfaces. The results prove that DBTPA coordinates with the perovskite by Lewis acid-base and cation-π interaction. Compared with the 19.9% efficiency of the pristine sample, the champion efficiency of the passivated sample reaches 20.6%. Our results reveal DBTPA as a new post-treating molecule that leads not only to the improvement of the photovoltaic efficiency but also thermal and moisture stability.

Background: The novel coronavirus disease (COVID-19) has created obstacles for medical student education, as clinical rotations were temporarily halted. Recent literature shows online electives may provide an alternative learning platform. We developed a tele-ophthalmology student elective for rising third-year (MS3) and fourth-year (MS4) medical students to continue teaching and exposure to the field., Methods: A 4-week remote elective was approved by Emory University School of Medicine and offered between April 18, 2020 to May 15, 2020 for rising MS3 and MS4 students. The curriculum consisted of online self-study materials, student presentations, chart review assignments, case-based discussions with faculty, and telehealth experiences. All students were surveyed and tested with questions from USMLE World (UWorld) test bank at the end of the course., Results: A total of 18 students enrolled, with 66.7% MS3 and 33.3% MS4 participance. The mean rating of fulfillment of course learning objectives was 8.1/10 (range, 6.7-8.8), with mean ratings of 8.2 for MS3s and 7.7 for MS4s. There was a significant increase in self-reported knowledge in ophthalmology, with an increase from 4.6 to 8.1 for MS3s (p=0.002) and 6.7 to 8.0 for MS4s (p=0.04). Students also reported higher interest in the field, with an increase from 4.9 to 7.8 for MS3s (p=0.01) and 7.5 to 8.7 for MS4s (p=0.1). The students performed significantly higher on the post-course test (94.8%) than UWorld question bank users (74.1%) (p<0.001)., Conclusion: Our novel ophthalmology elective significantly enhanced self-reported medical student knowledge and interest in the field during a crisis that required transition to remote learning. Further study of student telehealth experience and objective assessment is needed to improve online learning in ophthalmology., Competing Interests: Conflict of Interest: None declared.

Purpose: To test the antiseptic efficacy of povidone-iodine when mixed with topical lidocaine gel., Setting: Emory School of Medicine, Atlanta, Georgia, USA., Design: Experimental study., Methods: Staphylococcus epidermidis, Staphylococcus aureus, viridans streptococci (Streptococcus sanguinis), Escherichia coli, and Pseudomonas aeruginosa were grown on blood agar plates with povidone-iodine and/or lidocaine gel. The efficacy of sterilization was quantified by surviving bacterial colony-forming units., Results: Combination of povidone-iodine and lidocaine gel prevented bacterial growth to levels similar to povidone-iodine alone. Application of lidocaine gel to bacteria before povidone-iodine treatment allowed bacterial growth similar to controls not exposed to povidone-iodine., Conclusions: Povidone-iodine must be applied before lidocaine gel for effective antisepsis, but admixture of povidone-iodine with lidocaine gel was also effective and may reduce the risk of endophthalmitis associated with lidocaine gel use. This strategy offers a practice-changing alternative for preoperative prophylaxis in procedures requiring topical anesthesia.

Abnormalities in pupillary light reflex can indicate optic nerve disorders that may lead to permanent visual loss if not diagnosed in an early stage. In this study, we focus on relative afferent pupillary defect (RAPD), which is based on the difference between the reactions of the eyes when they are exposed to light stimuli. Incumbent RAPD assessment methods are based on subjective practices that can lead to unreliable measurements. To eliminate subjectivity and obtain reliable measurements, we introduced an automated framework to detect RAPD. For validation, we conducted a clinical study with lab-on-a-headset, which can perform automated light reflex test. In addition to benchmarking handcrafted algorithms, we proposed a transfer learning-based approach that transformed a deep learning-based generic object recognition algorithm into a pupil detector. Based on the conducted experiments, proposed algorithm RAPDNet can achieve a sensitivity and a specificity of 90.6% over 64 test cases in a balanced set, which corresponds to an AUC of 0.929 in ROC analysis. According to our benchmark with three handcrafted algorithms and nine performance metrics, RAPDNet outperforms all other algorithms in every performance category.

Ultrasound imaging using a matrix array allows real-time multi-planar volumetric imaging. To enhance image quality, the matrix array should provide fast volumetric ultrasound imaging with spatially consistent focusing in the lateral and elevational directions. However, because of the significantly increased data size, dealing with massive and continuous data acquisition is a significant challenge. We have designed an imaging acquisition sequence that handles volumetric data efficiently using a single 256-channel Verasonics ultrasound research platform multiplexed with a 1024-element matrix array. The developed sequence has been applied for building an ultrasonic pupilometer. Our results demonstrate the capability of the developed approach for structural visualization of an ex vivo porcine eye and the temporal response of the modeled eye pupil with moving iris at the volume rate of 30 Hz. Our study provides a fundamental ground for researchers to establish their own volumetric ultrasound imaging platform and could stimulate the development of new volumetric ultrasound approaches and applications.

Importance: Rear-facing sideview mirrors are a potentially reducible source of ocular morbidity following motor vehicle crashes., Objective: To report cases highlighting shattered glass from sideview mirrors as a potential cause of ocular trauma in motor vehicle crashes., Design, Setting, and Participants: Case series of 3 patients who presented to Grady Memorial Hospital, a level 1 trauma center and tertiary hospital, between May 5, 2017, and July 10, 2017, with ocular trauma as a result of shattered glass from sideview mirrors during motor vehicle crashes. A review of the literature was also conducted. Data were analyzed between July 2017 and August 2017., Interventions or Exposures: Operation for exploration and repair of open globe in all 3 cases., Main Outcomes and Measures: Visual prognosis and ocular morbidity postoperatively., Results: All patients were white men in the age range of 26 to 43 years. This was a retrospective review of 3 of 208 patients who presented to Grady Memorial Hospital after motor vehicle crashes from May 5, 2017, to July 10, 2017. From the time of presentation of the 3 reported patients from Grady Memorial Hospital, all 3 had 2 surgeries inclusive of the initial open globe repair. Patients with this mechanism of injury experienced ocular morbidity, with all 3 cases resulting in uveal prolapse and 2 of 3 resulting in retinal detachments. Among the 3 patients, visual acuities after the second surgery within the first year were hand motion, 20/100, and 20/150., Conclusions and Relevance: Sideview mirrors can be a cause of serious ocular injuries in motor vehicle crashes. These 3 reported cases, combined with cases previously reported, suggest that this mechanism of ocular injury does occur. Further studies seem warranted to investigate the frequency of these findings and whether any design modifications may help reduce the frequency.

The aim of this study was to assess the current state of automated pupillometry technology and its application in the neurointensive care unit (neuroICU). We performed a literature search using the PubMed, MEDLINE, and EMBASE databases from database inception through a search end date of October 18, 2018, to identify studies reporting on the use of automated pupillometry in the care of critically ill patients with neurological impairment. Two independent reviewers reviewed all titles and abstracts in two filtering phases. Data were extracted independently. One hundred and forty-one articles/abstracts have been published on the use of automated pupillometry in critical care since inception of the PubMed, MEDLINE, and EMBASE databases. We selected and reviewed 22 full-text articles and 8 abstracts, of which 26 were prospective, 2 were retrospective, and 2 were larger case series. Automated pupillometry increased precision, reliability, and reproducibility compared with the manual pupillary examination; detected subtle and early pupillary changes; detected pupillary changes that indicate a rise, or impending rise, in intracranial pressure detected level of analgesia and depth of sedation; served as a prognostic indicator; estimated the clinical severity of aneurysmal subarachnoid hemorrhage; and served as a noninvasive monitor of response to osmotic therapy. At present, no consensus guidelines exist endorsing routine use of automated pupillometry in the neuroICU. However, an increasing quantity of research supports the usefulness of automated pupillometry in this setting. Further large-scale prospective studies are needed before updated consensus guidelines recommending widespread adoption of automated pupillometry are produced.

Corneal endothelial cell (CEC) loss occurs from tissue manipulation during anterior segment surgery and corneal transplantation as well as from contact with synthetic materials like intraocular lenses and tube shunts. While several studies have quantified CEC loss for specific surgical steps, the vulnerability of CECs to isolated, controllable and measurable mechanical forces has not been assessed previously. The purpose of this study was to develop an experimental testing platform where the susceptibility of CECs to controlled mechanical trauma could be measured. The corneal endothelial surfaces of freshly dissected porcine corneas were subjected to a range of indentation forces via a spherical stainless steel bead. A cell viability assay in combination with high-resolution fluorescence microscopy was used to visualize and quantify injured/dead CEC densities before and after mechanical loading. In specimens subjected to an indentation force of 9 mN, the mean ± SD peak contact pressure P 0 was 18.64 ± 3.59 kPa (139.81 ± 26.93 mmHg) in the center of indentation and decreased radially outward. Injured/dead CEC densities were significantly greater (p ≤ 0.001) after mechanical indentation of 9 mN (167 ± 97 cells/mm 2 ) compared to before indentation (39 ± 52 cells/mm 2 ) and compared to the sham group (34 ± 31 cells/mm 2 ). In specimens subjected to "contact only" - defined as an applied indentation force of 0.65 mN - the peak contact pressure P 0 was 7.31 ± 1.5 kPa (54.83 ± 11.25 mmHg). In regions where the contact pressures was below 78% of P 0 (<5.7 kPa or 42.75 mmHg), injured/dead CEC densities were within the range of CEC loss observed in the sham group, suggesting negligible cell death. These findings indicate that CECs are highly susceptible to mechanical trauma via indentation, supporting the established "no-touch" policy for ophthalmological procedures. While CECs can potentially remain viable below contact pressures of 5.7 kPa (42.75 mmHg), this low threshold suggests that prevention of indentation-associated CEC loss may be challenging., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Purpose/Aim: Despite their importance in accurate mechanical modeling of the cornea, the depth-dependent material properties of the cornea have only been partially elucidated. In this work, we characterized the depth-dependent out-of-plane Young's modulus of the central and peripheral human cornea with high spatial resolution., Materials and Methods: Central and peripheral corneal buttons from human donors were subjected to unconfined axial compression followed by stress relaxation for 30 min. Sequences of fluorescent micrographs of full-thickness corneal buttons were acquired throughout the experiment to enable tracking of fluorescently labeled stromal keratocyte nuclei and measurements of depth-dependent infinitesimal strains. The nominal (gross) out-of-plane Young's modulus and drained Poisson's ratio for each whole specimen was computed from the equilibrium stress and overall tissue deformation. The depth-dependent (local) out-of-plane Young's modulus was computed from the equilibrium stress and local tissue strain based on an anisotropic model (transverse isotropy)., Results: The out-of-plane Young's modulus of the cornea exhibited a strong dependence on in-plane location (peripheral versus central cornea), but not depth. The depth-dependent out-of-plane Young's modulus of central and peripheral specimens ranged between 72.4-102.4 kPa and 38.3-58.9 kPa. The nominal out-of-plane Young's modulus was 87 ± 41.51 kPa and 39.9 ± 15.28 kPa in the central and peripheral cornea, while the drained Poisson's ratio was 0.05 ± 0.02 and 0.07 ± 0.04., Conclusions: The out-of-plane Young's modulus of the cornea is mostly independent of depth, but not in-plane location (i.e. central vs. peripheral). These results may help inform more accurate finite element computer models of the cornea.

Purpose: To evaluate the accuracy of eye bank-prepared precut donor corneas over time by comparing cut-failure rates and corneal thickness measurements in 2010 and 2013., Methods: A total of 2511 human corneas cut by a technician-operated mechanical microkeratome intended for endothelial keratoplasty were evaluated prospectively at one large eye bank facility in 2010 and in 2013. The endothelium was evaluated by slit lamp, and specular microscopy both before and after cutting was performed. Graft thickness as measured by pachymetry and/or optical coherence tomography was collected to assess the accuracy of the cut tissue. Cut-failure rates were compared between normal donor tissue and tissue with significant preexisting scarring., Results: The combined cut-failure rate in 2010 and 2013 was 2.3% (23/1000) and 1.6% (24/1511), respectively (P = 0.23). The cut-failure rate among normal tissue in 2010 and 2013 was 2.0% (19/927) and 1.4% (19/1400), respectively (P = 0.24). The cut-failure rate among previously scarred tissue in 2010 and 2013 was 5.5% (4/73) and 4.5% (5/111), respectively (P = 0.74). The mean surgeon-requested graft thickness was 144.7 μm (range 100-150, SD 13.6) and 127.2 μm (range 75-150, SD 25.2) in 2010 and 2013, respectively (P < 0.0001). The mean deviation from target graft thickness was 21.3 μm (SD 16.3) and 13.6 μm (SD 12.5) in 2010 and 2013, respectively (P < 0.0001)., Conclusions: From 2010 to 2013, the combined cut-failure rates trended toward improvement, while the accuracy of graft thickness improved. This study suggests that the accuracy and success rates of tissue preparation for endothelial keratoplasty improve with experience and volume.

Purpose: To compare 8 ophthalmology resident surgical training tools to determine which is most cost effective., Setting: University of Rochester Medical Center, Rochester, New York, USA., Design: Retrospective evaluation of technology., Methods: A cost-analysis model was created to compile all relevant costs in running each tool in a medium-sized ophthalmology program. Quantitative cost estimates were obtained based on cost of tools, cost of time in evaluations, and supply and maintenance costs., Results: For wet laboratory simulation, Eyesi was the least expensive cataract surgery simulation method; however, it is only capable of evaluating simulated cataract surgery rehearsal and requires supplementation with other evaluative methods for operating room performance and for noncataract wet lab training and evaluation. The most expensive training tool was the Eye Surgical Skills Assessment Test (ESSAT). The 2 most affordable methods for resident evaluation in operating room performance were the Objective Assessment of Skills in Intraocular Surgery (OASIS) and Global Rating Assessment of Skills in Intraocular Surgery (GRASIS)., Conclusions: Cost-based analysis of ophthalmology resident surgical training tools are needed so residency programs can implement tools that are valid, reliable, objective, and cost effective. There is no perfect training system at this time., (Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To characterize the depth-dependent shear modulus of the central and peripheral human cornea along the superior-inferior and nasal-temporal directions with a high spatial resolution., Methods: Cylindrical explants from the central and peripheral corneas of 10 human donors were subjected to a 5% shear strain along the superior-inferior and nasal-temporal directions using a microscope-mounted mechanical testing device. Depth-dependent shear strain and shear modulus were computed through force measurements and displacement tracking., Results: The shear modulus G of the human cornea varied continuously with depth, with a maximum occurring roughly 25% of the way from the anterior surface to the posterior surface. G also varied with direction in the superior region and (at some depths) was significantly higher for superior-inferior shear loading. In the anterior half of the cornea, the shear modulus along the nasal-temporal direction (GNT) did not vary with location; however, the superior region had significantly higher GNT in posterior cornea. In contrast, the shear modulus along the superior-inferior direction (GSI) was independent of location at all depths., Conclusions: This study demonstrates that the peak shear modulus of the human cornea occurs at a substantial distance within the corneal stroma. Depth-dependent differences between central and peripheral cornea possibly reflect the location-dependent mechanical environment of the cornea. Moreover, the cornea is not a transverse isotropic material, and must be characterized by more than a single shear modulus due to its dependence on loading direction. The material properties measured in this study are critical for developing accurate mechanical models to predict the vision-threatening morphological changes that can occur in the cornea., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)

Purpose: The aim of this study was to analyze Descemet stripping automated endothelial keratoplasty donor endothelial grafts, prepared by using a microkeratome, in terms of uniformity, circularity, and concentricity., Methods: In this pilot study, 12 human donor corneas were prepared by means of a microkeratome and imaged using the Visante anterior segment optical coherence tomography along 4 meridians. The microkeratome enters and exits the corneal tissue at an angle, creating a donor graft bed with a uniform stromal (US) thickness in between the angled edges. We termed the angled portion the "nonuniform stromal transitional annulus" (STA), the point of entry and exit of the microkeratome the "epithelium-to-epithelium" (E-E) diameter, and the length of the US bed the "US" diameter. The E-E and US diameters were measured to create a model of each donor graft, from which circularity and concentricity were calculated. The STA length and height were measured, and the slope was calculated., Results: The mean E-E diameter was 10.69 ± 0.32 mm (range, 9.46-11.75 mm) and the mean US diameter was 8.96 ± 0.40 mm (range, 7.62-10.28 mm). The microkeratome generated elliptical rather than circular cuts, with a mean eccentricity of 0.34 ± 0.098 (range, 0.22-0.58). Eccentricity values between 0 and 1 represent ellipses, with zero characterizing a circle. The US ellipses and E-E ellipses were not concentric, with a mean deviation of the centers of the shapes of 177.06 ± 92.06 μm (range, 21.95-322.22 μm). The mean STA length was 0.73 ± 0.31 mm (range, 0.25-1.89 mm), the mean height was 0.43 ± 0.08 mm (range, 0.28-0.64 mm), and the mean slope was 34.11 ± 14.00° (range, 8.43-53.67°)., Conclusions: Microkeratome cuts created nonuniform, noncircular nonconcentric donor grafts. Asymmetry and nonuniformity of donor tissue may help explain suboptimal visual outcomes.

Purpose: To report outcomes in Descemet stripping automated endothelial keratoplasty (DSAEK) using donor tissue from eyes that have had previous refractive surgery and to report histopathology of the donor free cap., Methods: Retrospective case series. Preoperative and postoperative data were collected on each patient, and donor information was collected. Histopathologic evaluation was carried out on donor caps to determine the stability of the laser in situ keratomileusis (LASIK) flap and smoothness of the microkeratome cut during preparation of the donor., Results: DSAEK was performed on 7 eyes using donors that had undergone photorefractive keratectomy (PRK) or LASIK. One patient received PRK donor tissue, had no interface haze, and had improvement in vision. All but one patient who received LASIK donor tissue had improvement in vision, and that patient had severe graft folds noted intraoperatively that persisted. Histopathologic examination of 3 donor caps showed mild to moderate dehiscence of the LASIK flap, but the cut interface was consistent with normal donor tissue preparation histopathology., Conclusions: We report the first case of DSAEK using PRK donor tissue, which was successful. Our experience with LASIK donor tissue was comparable to nonrefractive donor tissue with the exception of the persistent donor macrofolds in one patient.

Purpose: To describe a case of bilateral central toxic keratopathy (CTK) in a post-laser in situ keratomileusis-treated patient using tomographic methods for more than a 1-year follow-up., Methods: Case report and literature review., Results: Tomographic analysis of a patient with bilateral CTK revealed flattening of the anterior cornea curvature and thinning at the level of anterior stromal bed, with minimal changes of the posterior curvature. A thin central flap was also noted on optical coherence tomography (OCT). Over the course of a year, the patient's hyperopic shift resolved with steepening of the anterior curvature and concomitant thickening of the flap and stromal bed., Conclusions: Using Scheimpflug imaging and Visante OCT, we demonstrated that the hyperopia that accompanies CTK is related to anterior corneal curvature changes. We also found that the majority of corneal tissue loss occurs at the anterior stromal bed mainly in the first postoperative week and is followed by a regeneration of tissue. A thin central flap was noted, and it is not clear whether this was created intraoperatively or resulted from the presence of CTK, requiring further study.

Purpose: To report a case of keratitis and corneal melt after conductive keratoplasty (CK) enhancement., Method: Case report., Results: A 52-year-old woman with emmetropic presbyopia had undergone previous CK for monovision and underwent CK enhancement 4 years later. Postoperatively, she was managed with ketorolac tromethamine 0.4% and developed keratitis and corneal melt., Conclusions: This is the first reported case of keratitis and corneal melt associated with nonsteroidal antiinflammatory topical medications in a post-CK patient.

Purpose: To evaluate the efficacy of 3 different surgical techniques for convergence excess esotropia: augmented medial rectus recession, medial rectus recession plus Faden, and slanted medial rectus recession., Methods: Twenty-nine patients with convergence excess esotropia were divided into 3 groups. Group A included 9 patients treated with medial rectus muscle recession augmented with 1-2 mm more of the standard recession. Group B included 10 patients treated with standard recession plus Faden. Group C included 10 patients treated with slanted medial rectus recession. Surgical success was defined as esotropia (ET) 10 prism diopters (Δ) or less at distance and near with collapse of distance/near disparity., Results: Satisfactory alignment with elimination of bifocal correction was noted in group A (66.6%). In groups B and C, the results were 70%. Group A patients had a mean reduction in distance/near disparity from 15.5±1.5Δ prism diopters preoperatively to 4.7±2.5Δ prism diopters postoperatively, while in group B the preoperative distance/near disparity was 16.5±1.8Δ prism diopters and decreased to 3.8±3.1Δ prism diopters postoperatively, and group C also showed reduction in distance/near disparity from 18.1±1.6Δ prism diopters preoperatively to 4.5±3.6Δ prism diopters postoperatively. There were no statistically significant differences among the 3 groups., Conclusions: The 3 procedures are effective surgical options to treat convergence excess esotropia with acceptable motor outcomes.

To report a case of ocular surface squamous neoplasia (OSSN) masquerading as superior limbic keratoconjunctivitis (SLK). A 62-year-old woman was referred with foreign body sensation, irritation, photophobia and decreased vision in the left eye. She was initially treated for 10 months with intermittent topical corticosteroids for a presumed diagnosis of SLK. She underwent excisional biopsy of the superior conjunctiva and was found, on histopathologic evaluation, to have OSSN with moderate to marked dysplasia. This is the first reported case of OSSN masquerading with signs and symptoms of SLK. Any ocular surface lesion refractory to standard medical treatment should raise suspicion for a malignant process and warrant further cytologic or histopathologic evaluation.

Purpose: To report a case of bilateral non-pupillary block angle closure glaucoma after Visian Implantable Collamer Lens (ICL, STAAR Surgical) surgery., Methods: A 35-year-old woman with high myopia, white-to-white measurements of 11.8 mm in the right eye and 11.9 mm in the left eye, and anterior chamber depths >3 mm in both eyes underwent simultaneous bilateral ICL implantation with 13.2-mm lenses., Results: Persistent, bilateral acute angle closure developed despite multiple patent peripheral iridotomies and iridectomies. Visante anterior segment optical coherence tomography (AS-OCT, Carl Zeiss Meditec) revealed profound vaulting of the ICLs and angle closure. Both ICLs were explanted. After explantation, ultrasound biomicroscopy demonstrated a sulcus-to-sulcus diameter of 10.8 mm in the right eye and 11.2 mm in the left eye., Conclusions: The correlation between white-to-white and sulcus-to-sulcus measurements were poor in this patient, resulting in extreme vaulting of the ICL and angle closure from a non-pupillary block mechanism. Proper identification of the mechanism of angle closure is aided by AS-OCT. For non-pupillary block mechanisms, ICL extraction is necessary., (Copyright 2010, SLACK Incorporated.)

Purpose: To report a case of unilateral localized sectoral conjunctival amyloidosis associated with corneal amyloidosis., Methods: Case report., Results: A 27-year-old woman with a history of ocular trauma presented with a limbus-based pink-yellow colored superonasal conjunctival lesion with adjacent superonasal sectoral corneal lattice-like changes. The lesion was monitored for 3 years with minimal enlargement, but conjunctival chalasis developed, which was bothersome to the patient. A conjunctival excisional biopsy confirmed the diagnosis of amyloidosis., Conclusions: To our knowledge, this is the first report of unilateral combined corneal and conjunctival amyloid deposition. Even more unusual was the sectoral distribution of the amyloid. This likely represents a local production and deposition of amyloid.

We report the histopathology of epithelial overgrowth in the Boston type I keratoprosthesis. The epithelium shows an inconsistent number of layers and basement membrane and goblet cells are absent. Epithelialization of the keratoprosthesis optic would have multiple advantages, but the limitation of vision makes tolerating the overgrowth difficult.

Purpose: To assess the histopathology of anterior subcapsular cataract associated with a collagen copolymer posterior chamber phakic intraocular lens (pIOL) (Visian Implantable Collamer Lens) using light microscopy after pIOL explantation and cataract surgery., Setting: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA., Design: Laboratory investigation., Methods: Pathology specimens related to explanted pIOLs were reviewed and preoperative and postoperative patient data collected. The anterior lens capsules and explanted pIOLs were examined., Results: Four eyes (3 patients) had pIOL explantation for low vault and anterior subcapsular cataract. The explanted pIOLs were the shorter length models (3, 12.1 mm; 1, 12.6 mm). Anterior segment optical coherence tomography (AS-OCT) confirmed the low pIOL vault before explantation in 2 eyes. Histopathology of the anterior subcapsular cataract showed fibrous metaplasia with a variable number of lens epithelial cell (LEC) layers attached to the inner surface of the anterior capsulorhexis specimens. Light microscopy of the explanted pIOLs showed no pigment on 1 lens, mild pigment deposition on 1 haptic, and pigment deposition throughout the anterior surface of 2 pIOLs., Conclusions: Anterior subcapsular cataract associated with the pIOLs was caused by low vaulting (confirmed on AS-OCT) and consequent fibrous metaplasia of the anterior LECs. Surgeons should consider the possibility of anterior subcapsular cataract associated with shorter platforms when selecting a pIOL length for appropriate vault., (Copyright © 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To report a case of nontraumatic corneal perforation managed with a tectonic drape patch., Methods: Interventional case report., Results: A 60-year-old patient with a corneal scar in his left eye likely secondary to herpes simplex virus interstitial keratitis underwent laser peripheral iridotomy for narrow angles. He developed progressive thinning of the cornea overlying the scar that led to a descemetocele and then ultimately a 1.2- × 1.7-mm perforation. Intraoperatively, several attempts were made to seal the perforation with cyanoacrylate glue, but the wound continued to leak. Sterile plastic drape that was on the surgical field was fashioned into a 2-mm-diameter patch, and the peripheral edge of the tectonic drape patch was glued over the perforation, successfully sealing the cornea. One week later, the drape patch was intact without leak, and a penetrating keratoplasty was carried out without complication., Conclusions: Tectonic drape patch technique for nontraumatic corneal perforations in which there is tissue loss is a viable temporizing option when cyanoacrylate glue alone fails and when there is no corneal tissue or amniotic membrane available to close the wound.

The type 1 Boston Keratoprosthesis preparation requires a 3-mm central punch and an 8.5 mm or larger punch in the carrier tissue. These punches are ideally concentric, but we have found difficulty in achieving concentric punches when the larger punch is performed first. We present a modification in the preparation procedure to help minimize centration error.