Selective Modulation of the Keratoconic Stromal Microenvironment by FSH and LH.

Keratoconus (KC) affects the corneal structure, with thinning and bulging outward into a conelike shape. Irregular astigmatism and decreased visual acuity appear during puberty and progress into the mid-30s, with unpredictable disease severity. The cause of KC is recognized as multifactorial, but remains poorly understood. Hormone imbalances are a significant modulator of the onset of KC. This study sought to investigate the role of gonadotropins, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in KC, using a three-dimensional, self-assembled matrix in vitro model. Healthy corneal fibroblasts and human KC cells in the corneal stroma were isolated, cultured, and stimulated with stable vitamin C to promote extracellular matrix assembly. Cultures were further stimulated with 2.5 or 10 mIU/mL FSH and 5 or 35 mIU/mL LH. Samples were evaluated for cell proliferation and morphology via BrdU assay and imaging; protein expression was assessed via Western blot analysis. Proliferation was significantly greater in human KC cells compared to healthy corneal fibroblasts with LH stimulation, but no changes were found with FSH stimulation. Additionally, in sex hormone receptors, fibrotic markers, proteoglycans, and members of the gonadotropin signaling pathway were significantly changed, largely driven by exogenous LH. The impact of exogenous FSH/LH in the KC stromal microenvironment was demonstrated. These results highlight the need to further examine the role of FSH/LH in KC and in human corneal homeostasis.

Current trends in the management of corneal neovascularization.

PURPOSE OF REVIEW: The aim of this study was to highlight recent developments in the medical and surgical management of corneal neovascularization (NV). RECENT FINDINGS: Improved understanding and diagnostic criteria among clinicians have led to advancements in the characterization of corneal NV and objective assessment of treatment response through ancillary imaging devices. Developments in corneal NV treatments, such as antivascular endothelial growth factor, fine needle diathermy, and photodynamic therapy, have improved treatment success rates and visual outcomes. More recent surgical treatment advancements include corneal cross-linking, endothelial keratoplasty, and mitomycin intravascular chemoembolization. Finally, a greater appreciation of the molecular pathogenesis and angiogenic factors involved in corneal NV has identified numerous potential targeted therapies in the future. SUMMARY: The management of corneal NV has evolved to include several standalone and combination medical and surgical options. Additionally, improvements in quantifying corneal NV and understanding its molecular basis have contributed to new management strategies with improved outcomes.

DIAGNOSTIC PATTERNS OF AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To characterize prevalence estimates by race, age, sex, and comorbidity (diabetes and hypertension) within the Medicare beneficiary demographic. METHODS: In this US population-based retrospective cohort analysis, the Vision and Eye Health Surveillance System was analyzed for a 100% sample of Medicare Fee-For-Service beneficiary populations of Asians and non-Hispanic Whites between 2014 and 2018. Exclusionary criteria included beneficiaries younger than 40 years. Prevalence rate ratios, defined as prevalence rate for Asians divided by prevalence rate for non-Hispanic Whites, were calculated using multivariate negative binomial regression or Pearson-scaled Poisson regression, stratified by age, sex, and comorbidity. RESULTS: A total of 21,892,200 Medicare beneficiaries fulfilled the inclusionary criteria in 2018. Of the entire cohort, 3.2% of the beneficiaries (N = 714,500) were Asian. For beneficiaries aged 40 to 64 years, Asian male (prevalence rate ratios 1.73, 95% confidence interval 1.64-1.83, P < 0.0001) and female (prevalence rate ratios 1.34, 95% confidence interval 1.28-1.41, P < 0.0001) beneficiaries had an increased prevalence rate of all age-related macular degeneration relative to non-Hispanic Whites. Significant time-wise increases in prevalence rate ratios were observed within several age groups, sexes, and comorbidities (race-time interaction coefficients P < 0.05 ). CONCLUSION: This analysis highlights increased age-related macular degeneration prevalence estimates within the Asian American demographic relative to non-Hispanic Whites. Furthermore, specific Asian subpopulations are experiencing accelerated prevalence rates over time.

Optic Nerve Sheath Meningiomas: A National Surveillance, Epidemiology, and End Results (SEER) Database Analysis.

BACKGROUND: Optic nerve sheath meningioma (ONSM) is a rare optic nerve cancer with considerable morbidity. This national analysis validates previously known ONSM concepts while providing insight into novel risk factors. METHODS: The Surveillance, Epidemiology, and End Results (SEER) Program was queried from 2000 to 2019 for all histologic subtypes of meningioma primary to the optic nerve. Relevant clinical and demographic variables were analyzed. Asymptotic one-sample test for binomial proportions and Cox proportional hazards modeling evaluated the significance of factor associations. RESULTS: A total of 51 ONSM cases were extracted. A greater proportion of cases were observed in females (N = 37, 73% , P < 0.001) and individuals with age 50 years or more (N = 29, 57% , P < 0.001); the mean number of months from diagnosis to treatment was 4.6 months (SD 4.1, range 13). Psychosocial epidemiologic parameter analysis demonstrated a greater proportion of patients with married status on diagnosis (N = 31, 61% , P < 0.001), listed total family income between $55,000 and $74,999 (N = 24, 47% , P < 0.001). Relative to cases diagnosed clinically only, cases diagnosed radiologically without microscopic confirmation experienced decreased all-cause mortality (HR = 0.041, P = 0.050). CONCLUSIONS: Our SEER national analysis affirms previously characterized ONSM concepts. Upon ONSM diagnosis and if needed, treatment protocols are not significantly delayed. Novel psychosocial factors for ONSM were identified, including marital status, total family income, and non-Hispanic white race. Additional ONSM diagnostics may reduce longitudinal mortality burden.

Unilateral intraindividual comparison and bilateral performance of a monofocal spherical and diffractive extended depth of field intraocular lens mix-and-match approach.

BACKGROUND: To evaluate the intraindividual visual performance of a spherical and extended depth of field (EDOF) IOL used in a mix-and-match approach. METHODS: Single centre (tertiary care centre), retrospective consecutive case series. Included patients had uneventful cataract surgery with implantation of a spherical monofocal IOL (CT Spheris 204) in the dominant eye and a diffractive EDOF IOL (AT LARA 829) in the non-dominant eye. Monocular and binocular defocus curves and visual acuity at various distances were assessed. In addition, binocular reading speed, contrast sensitivity, and patient satisfaction using QOV, Catquest 9SF, and glare/halo questionnaires are reported. RESULTS: A total of 29 patients (58 eyes) were included. We observed significant intra-individual differences for monocular DCIVA, DCNVA, UIVA, and UNVA. There were no differences in monocular BCDVA or UDVA. The monocular defocus curves for the two IOLs significantly differed at defocus steps between -1.0 and -3.5 D. 93.10% of patients reported they would opt for the same combination of IOLs. CONCLUSION: Excellent uncorrected and corrected distance visual acuity was demonstrated in both groups. The mix-and-match approach described in this study yielded good intermediate vision and improved near vision with high-patient satisfaction.

Pediatric herpes zoster ophthalmicus: a systematic review.

PURPOSE: While typically affecting older adults and immunocompromised individuals, herpes zoster ophthalmicus (HZO) has been reported with varying manifestations and complications in children. In this review, we evaluate reported cases of pediatric HZO in the literature and discuss the epidemiology, risk factors, clinical presentation, treatment and outcomes. METHODS: A literature search on PubMed, Scopus, and Web of Science databases was performed using the terms "pediatric herpes zoster ophthalmicus" and "herpes zoster ophthalmicus children." Publications that were not specific to HZO or pediatric populations were excluded, as were publications that were not available to review or not published in the English language. RESULTS: Fifty-seven reports describing 130 cases of HZO or HZO-related complications were reviewed. Major risk factors for pediatric HZO included intrauterine exposure to varicella or primary varicella infection at a young age; HZO also occurred in patients who had received varicella vaccination. Both healthy and immunocompromised children were affected, with the majority of affected children being immunocompetent. The diagnosis of HZO is primarily clinical. Children appear to have good vision recovery and resolution of symptoms if they are treated promptly and if they adhere to treatment regimens, except for irreversible vision loss related to uncommon complications such as optic neuritis. CONCLUSION: HZO occurs in both healthy and immunocompromised children. Recognizing this treatable condition is essential for reducing ocular and systemic morbidity. Long-term follow-up and assessments of the impact on health in adulthood are lacking. More systematic study is needed to determine the incidence of HZO in children and appropriate diagnostic and treatment protocols for the care of pediatric patients with HZO.

Dry eye in the upper blepharoplasty patient: a study comparing orbicularis-sparing versus orbicularis-excising techniques.

PURPOSE: To compare subjective and objective dry eye syndrome (DES) metrics preoperatively and postoperatively in patients undergoing bilateral upper eyelid blepharoplasty (ULB) using orbicularis-sparing versus orbicularis-excising techniques. METHODS: A double-blind, randomized clinical trial was conducted on patients without prior DES or other severe conditions who presented to our institution between 2017 and 2019 for routine functional ULB. Patients were randomized into two treatment arms: bilateral ULB using the orbicularis-sparing technique or bilateral ULB using the orbicularis-excising technique. One subjective and seven objective DES assessments were performed on all patients preoperatively and 1 month and 1 year after surgery. RESULTS: A total of 63 patients were recruited for the study. Standard Patient Evaluation of Eye Dryness (SPEED) scores decreased in both treatment groups at 1 month and 1 year postoperatively. This change did not significantly vary based on surgical technique. Objective DES assessments were not significantly changed at both postoperative time points for either group. There was a correlation between the severity of preoperative DES symptoms and the subjective improvement of DES symptoms postoperatively in both groups. CONCLUSIONS: ULB with an orbicularis-sparing or orbicularis-excising technique does not worsen subjective or objective DES metrics and so, surgeons may confidently use either surgical technique. These findings may impact postoperative expectations for surgeons and patients alike.

Revealing the presence of tear extracellular vesicles in Keratoconus.

Extracellular vesicles (EVs) are lipid-bound vesicles that originate from the endosomal system or budded off from the plasma membrane. EVs are involved in cell-cell communication via transporting DNA, RNA, and proteins from one cell to another. Tear EVs (tEVs) have been reported in dry eye, SjÓ§gren's Syndrome, and primary open-angle glaucoma. In this study, we sought to investigate the presence of tEVs in relation to keratoconus (KC). Tears were passively collected from the lateral meniscus from 10 healthy (5 males and 5 females) and 9 KC (4 males and 5 females) subjects. Tear samples were processed and analyzed using the ExoView™ R100. Statistical analysis was performed using a Mann-Whitney U non-parametric Student's t-test. All tEVs, in both Healthy and KC subjects, showed a CD9+ dominant tEV cohort independent of sex. A significant decrease in CD63+/CD9+ and CD63+/CD81+/CD9+ was found in the male KC tEVs (p < 0.05), but not in females compared to their healthy counterparts. Neither Healthy nor KC tEVs showed differences in the total number of tEVs, however significant differences were identified between the sexes (p < 0.05), with males having a higher number of tEVs. tEVs diameters ranged from 50 to 200 nm, in both Healthy and KC cohorts, with the majority in the 50-80 nm range suggesting exosome-dominant cohorts. To our knowledge, this is the first time, to date, that tEVs have been isolated and characterized in KCs. While further studies are warranted, the tEVs differences between KC and Healthy subjects suggest a potential role for tEVs in KC pathogenesis.

Frugal Method of Notch Modification of Scleral Contact Lenses in the Setting of Complex Ocular Surface Anatomy.

ABSTRACT: Scleral contact lenses (ScCLs) have gained popularity as a treatment of refractive errors in patients with complex anterior segment pathology. Patients with mechanical abnormalities of the ocular surface may be unsuccessful with traditional ScCL fitting. Scleral contact lens modifications, such as notching and microvaulting, typically incur additional financial costs and require the services of professional laboratories. We describe a frugal method of ScCL notch modification that can be performed by a practitioner using readily available tools in a single office visit. Two patients with abnormal ocular surface anatomy were fit with the practitioner-modified ScCL and achieved successful visual rehabilitation. We offer this method as a potentially economical and effective technique to achieve successful ScCL fitting in this challenging patient population with pathologies that may preclude standard ScCL usage.

Unravelling Novel Roles of Salivary Exosomes in the Regulation of Human Corneal Stromal Cell Migration and Wound Healing.

Salivary exosomes have demonstrated vast therapeutic and diagnostic potential in numerous diseases. This study pioneers previously unexplored roles of SE in the context of corneal wound healing by utilizing primary corneal stromal cells from healthy (HCFs), type I diabetes mellitus (T1DMs), type II DM (T2DMs), and keratoconus (HKCs) subjects. Purified, healthy human SEs carrying tetraspanins CD9+, CD63+, and CD81+ were utilized. Scratch and cell migration assays were performed after 0, 6, 12, 24, and 48 h following SE stimulation (5 and 25 µg/mL). Significantly slower wound closure was observed at 6 and 12 h in HCFs with 5 µg/mL SE and T1DMs with 5 and 25 µg/mL SE. All wounds were closed by 24-hour, post-wounding. HKCs, T1DMs, and T2DMs with 25µg/mL SE exhibited a significant upregulation of cleaved vimentin compared to controls. Thrombospondin 1 was significantly upregulated in HCFs, HKCs, and T2DMs with 25 µg/mL SE. Lastly, HKCs, T1DMs, and T2DMs exhibited a significant downregulation of fibronectin with 25 µg/mL SE. Whether SEs can be utilized to clinical settings in restoring corneal defects is unknown. This is the first-ever study exploring the role of SEs in corneal wound healing. While the sample size was small, results are highly novel and provide a strong foundation for future studies.

The Role of Estriol and Estrone in Keratoconic Stromal Sex Hormone Receptors.

Keratoconus (KC) is a progressive corneal thinning disease that manifests in puberty and worsens during pregnancy. KC onset and progression are attributed to diverse factors that include: environmental, genetics, and hormonal imbalances; however, the pathobiology remains elusive. This study aims to determine the role of corneal stroma sex hormone receptors in KC and their interplay with estrone (E1) and estriol (E3) using our established 3D in vitro model. Healthy cornea stromal cells (HCFs) and KC cornea stromal cells (HKCs), both male and female, were stimulated with various concentrations of E1 and E3. Significant changes were observed between cell types, as well as between males and females in the sex hormone receptors tested; androgen receptor (AR), progesterone receptor (PR), estrogen receptor alpha (ERα), and estrogen receptor beta (ERß) using Western blot analysis. E1 and E3 stimulations in HCF females showed AR, PR, and ERß were significantly upregulated compared to HCF males. In contrast, ERα and ERß had significantly higher expression in HKC's females than HKC's males. Our data suggest that the human cornea is a sex-dependent, hormone-responsive tissue that is significantly influenced by E1 and E3. Therefore, it is plausible that E1, E3, and sex hormone receptors are involved in the KC pathobiology, warranting further investigation.

Update on Biometry and Lens Calculation - A Review of the Basic Principles and New Developments. / Update Biometrie und Linsenberechnung ­ ein Review zu Grundlagen und neuen Entwicklungen.

These days, accurate calculation of artificial lenses is an important aspect of patient management. In addition to the classic theoretical optical formulae there are a number of new approaches, most of which are available as online calculators. This review aims to explain the background of artificial lens calculation and provide an update on study results based on the latest calculation approaches. Today, optical biometry provides the computational basis for theoretical optical formulae, ray tracing, and also empirical approaches using artificial intelligence. Manufacturer information on IOL design and IOL power recorded as part of quality control could improve calculations, especially for higher IOL powers. With modern measurement data, there is further potential for improvement in the determination of the axial length to the retinal pigment epithelium and by adopting a sum-of-segment approach. With the available data, the cornea can be assumed to be a thick lens. The Kane formula, the EVO 2.0 formula, the Castrop formula, the PEARL-DGS, formula and the OKULIX calculation software provide consistently good results for artificial lens calculations. Excellent refractive results can be achieved using these tools, with approximately 80% having an absolute prediction error within 0.50 dpt, at least in highly selected study populations. The Barrett Universal II formula also produces excellent results in the normal and long axial length range. For eyes with short axial lengths, the use of Barrett Universal II should be reconsidered; in this case, one of the methods mentioned above is preferable. Second Eye Refinement can also be considered in this patient population, in conjunction with established classic third generation formulae.

Biometry and Intraocular Lens Power Calculation in Eyes with Prior Laser Vision Correction (LVC) - A Review.

BACKGROUND: An intraocular lens (IOL) calculation in eyes that have undergone laser vision correction (LVC) poses a significant clinical issue in regards to both patient expectation and accuracy. This review aims to describe the pitfalls of IOL power calculation after LVC and give an overview of the current methods of IOL power calculation after LVC. REVIEW: Problems after LVC derive from the measurement of anterior corneal radii, central corneal thickness, asphericity, and the predicted effective lens position. A central issue is that most conventional 3rd generation formulas estimate lens position amongst other parameters on keratometry, which is altered in post-LVC eyes. CONCLUSION: An IOL power calculation results in eyes with prior LVC that are notably impaired in eyes without prior surgery. Effective corneal power including anterior corneal curvature, posterior corneal curvature, CCT (central corneal thickness), and asphericity is essential. Total keratometry in combination with the Barrett True-K, EVO (emmetropia verifiying optical formula), or Haigis formula is relatively uncomplicated and seems to provide good results, as does the Barrett True-K formula with anterior K values. The ASCRS ( American Society of Cataract and Refractive Surgery) calculator combines results of various formulae and averages results, which allows a direct comparison between the different methods. Tomography-based raytracing and the Kane and the Castrop formulae need to be evaluated by future studies.

Progression From Soft Lens to Piggyback Soft-Scleral Contact Lens System to Facilitate Scleral Lens Use in a Pediatric Patient.

ABSTRACT: Traumatic injury in the pediatric population often results in significant refractive errors that if left untreated can lead to amblyopia. Scleral contact lenses (ScCLs) have recently gained popularity in this population for efficacy in treatment of significant refractive errors, including irregularity astigmatism and corneal abnormalities. Scleral contact lens intolerance may limit the ability of practitioners to use this modality. Although a soft contact lens (SCL) is generally well tolerated, it cannot treat refractive error as effectively as an ScCL. We recently used an SCL followed by an SCL-ScCL combination ("piggyback" system) sequence in a pediatric patient to facilitate use of an ScCL alone. We hope that our results may provide practitioners with an additional option when treating this challenging patient population.

A randomized, controlled trial of video supplementation on the cataract surgery informed consent process.

PURPOSE: To assess the effects of the American Academy of Ophthalmology's 2015 patient education video on patient information retention and anxiety preoperatively, on the day of surgery and postoperatively. METHODS: This is a prospective, surgeon-blinded randomized controlled trial at the University of Chicago Medical Center. Ninety-one patients with a diagnosis of first-eye cataract were randomized into either a video or control group. Subjects in both groups received face-to-face discussion with the surgeon and an informational brochure at the preoperative evaluation. Participants in the video group then viewed a four-minute educational video at the preoperative evaluation and on the day of surgery. Both groups completed an information retention quiz and a state anxiety assessment at the preoperative visit, on the day of surgery, and on the postoperative week one visit. Subject understanding of cataract surgery was measured using a twelve-question multiple choice quiz. State anxiety was measured by State Trait Anxiety Inventory-Y1 survey score. RESULTS: Participants in the video group did not score significantly higher on the information retention quiz compared with the control group at the preoperative evaluation (8.7 ± 2.4 vs 7.7 ± 2.5, P = 0.07), but did so on the day of surgery (11.2 ± 0.8 vs 8.4 ± 1.7, P < 0.001) and postoperative week 1 visit (10.8 ± 1.5 vs 9.0 ± 2.0, P < 0.001). Subjects in the video group were significantly less anxious on the day of surgery (26.4 ± 5.1 vs 41.1 ± 10.3, P < 0.001). CONCLUSIONS: Video supplementation to the traditional informed consent process demonstrated an improvement in patient understanding of cataract surgery at multiple timepoints and decreased anxiety on the day of surgery.

Medically reversible limbal stem cell disease: clinical features and management strategies.

PURPOSE: To describe the clinical features and management strategies in patients whose limbal stem cell (LSC) disease reversed with medical therapy. DESIGN: Retrospective case series. PARTICIPANTS: Twenty-two eyes of 15 patients seen at 3 tertiary referral centers between 2007 and 2011 with 3 months or more of follow-up. METHODS: Medical records of patients with medically reversible LSC disease were reviewed. Demographic data, causes, location and duration of disease, and medical inventions were analyzed. MAIN OUTCOME MEASURES: Primary outcomes assessed included resolution of signs of LSC disease and improvement in visual acuity. RESULTS: Causes of the LSC disease included contact lens wear only (13 eyes), contact lens wear in the setting of ocular rosacea (3 eyes), benzalkonium chloride toxicity (2 eyes), and idiopathic (4 eyes). Ophthalmologic findings included loss of limbal architecture, a whorl-like epitheliopathy, or an opaque epithelium arising from the limbus with late fluorescein staining. The superior limbus was the most common site of involvement (95%). The corneal epithelial phenotype returned to normal with only conservative measures, including lubrication and discontinuing contact lens wear in 4 patients (4 eyes), whereas in 11 patients (18 eyes), additional interventions were required after at least 3 months of conservative therapy. Medical interventions included topical corticosteroids, topical cyclosporine, topical vitamin A, oral doxycycline, punctal occlusion, or a combination thereof. All eyes achieved a stable ocular surface over a mean follow-up of 15 months (range, 4-60 months). Visual acuity improved from a mean of 20/42 to 20/26 (P < 0.0184). CONCLUSIONS: Disturbances to the LSC function, niche, or both may be reversible with medical therapy. These cases, which represent a subset of patients with LSC deficiency, may be considered to have LSC niche dysfunction.

Mitomycin intravascular chemoembolization (MICE) to treat corneal vascularization prior to penetrating keratoplasty.

Purpose: To present the clinical outcome of mitomycin intravascular chemoembolization (MICE) as a prophylactic treatment in a patient with HSV-induced corneal neovascularization (NV) before penetrating keratoplasty (PKP). Observations: A 53-year-old male patient presented with a medical history of recurrent herpes simplex virus (HSV) corneal infection. The patient reported worsening visual acuity despite maintenance treatment with systemic antivirals and topical corticosteroids. After the appearance of corneal NV, subconjunctival triamcinolone and bevacizumab injections were given with limited and temporary improvement. Due to worsening corneal NV, MICE was subsequently performed, resulting in the elimination of corneal NV from the visual axis, which allowed for successful PKP 4 months later. Cataract surgery was performed 6 months after PKP. Conclusions and importance: This report describes the potential efficacy of MICE as a prophylactic treatment for corneal NV prior to PKP.

Noninfectious Outcomes of Intravitreal Antibiotic Steroid Injection and Topical Nonsteroidal Antiinflammatory Drugs Versus Triple Drop Therapy After Cataract Surgery.

PURPOSE: To compare noninfectious outcomes of intravitreal antibiotic steroid (IVAS) injection (moxifloxacin-triamcinolone) and postoperative topical nonsteroidal antiinflammatory drugs (NSAID) with a standard 3-drop therapy (TDT) regimen (topical antibiotic, steroid, and NSAID) in patients after cataract surgery. DESIGN: Retrospective comparative clinical cohort study. METHODS: In 3 study centers in the United States, a total of 2143 eyes (N = 2143 patients) underwent cataract surgery with IVAS-NSAID or TDT between 2017 and 2022. Preoperative data were included, including patients' age, iris color, medical history, and ocular history. Postoperative data, including best-corrected visual acuity, intraocular pressure (IOP), and the need for IOP-lowering medications, were recorded at 1-week, 1-month, and 6-month time points. The primary outcome measures were postoperative complications, defined as persistent anterior chamber inflammation, persistent corneal edema (PCE), rebound inflammation, and cystoid macular edema, were compared between the 2 groups. RESULTS: There were 1079 eyes in the IVAS-NSAID group and 1064 eyes in the TDT group. Best-corrected visual acuity and IOP were similar between IVAS-NSAID and TDT eyes at all time points. A portion (11.6%) of TDT eyes experienced postoperative complications compared with 6.5% in IVAS-NSAID eyes (P < .001). Femtosecond laser-assisted cataract surgery was associated with increased rates of PCE in IVAS-NSAID eyes, and eyes with dark irides had a higher incidence of cystoid macular edema, PCE, and rebound inflammation in the IVAS-NSAID group. CONCLUSION: The IVAS-NSAID regimen overall had similar postoperative outcomes and fewer complications compared with the TDT regimen. IVAS-NSAID may be considered a safe alternative to topical regimens in non-femtosecond laser-assisted cataract surgery and patients with light irides.

Updating the no-history method in intraocular lens power calculation after myopic laser vision correction.

PURPOSE: To describe the Shammas-Cooke formula, an updated no-history (NH) formula for IOL calculation in eyes with prior myopic laser vision correction (M-LVC), and to compare the results with the Shammas PL, Haigis-L, and Barrett True-K NH formulas. SETTING: Bascom Palmer Eye Institute (BPEI), The Lennar Foundation Medical Center, University of Miami, Miami, Florida; Dean A. McGee Eye Institute (DMEI), University of Oklahoma, Oklahoma City, Oklahoma; and private practice, Lynwood, California, and St Joseph, Michigan. DESIGN: Retrospective observational study. METHODS: We analyzed 2 large series of cataractous eyes with prior M-LVC. The training set (BPEI series of 330 eyes) was used to derive the new corneal power conversion equation to be used in the new Shammas-Cooke formula and the testing set (165 eyes of 165 patients in the DMEI series) to compare the updated formula with 3 other M-LVC NH formulas on the ASCRS calculator: Shammas PL, Haigis-L, and Barrett True-K NH. RESULTS: Mean prediction error was 0.09 ± 0.56 diopters (D), -0.44 ± 0.61 D, -0.47 ± 0.59 D, and -0.18 ± 0.56 D and the mean absolute error was 0.43 D, 0.60 D, 0.61 D, and 0.45 D for the Shammas-Cooke, Shammas PL, Haigis-L, and Barrett True-K NH, respectively. The percentage of eyes within ±0.50 D was 66.7% vs 47.9%, 48.5%, and 65.5%, respectively. CONCLUSIONS: The Shammas-Cooke formula performed better than the Shammas PL and Haigis-L (P < .001 for both) and as well as the Barrett True-K NH formula (P = .923).