Publications by authors named "Yasmyne C Ronquillo"

51 Publications

Comparison of 6.0 mm versus 6.5 mm Optical Zone on Visual Outcomes after LASIK.

J Clin Med 2021 Aug 24;10(17). Epub 2021 Aug 24.

Hoopes Vision Research Center, Hoopes Vision, Draper, UT 84020, USA.

Previous studies have demonstrated safety and efficacy using 6.0 and 6.5 mm optical zones in the WaveLight EX500 Excimer Laser System but have not evaluated if differing optical zone sizes influence refractive outcomes. This study examines visual outcomes between two study populations undergoing LASIK with either a 6.0 mm (1332 patients) or 6.5 mm (1332 patients) optical zone. Outcomes were further stratified by severity of myopia (low, moderate, and high) and astigmatism (low and high). Patients were matched by age and preoperative manifest sphere and cylinder. Postoperative measurements were then compared. The 6.5 mm group demonstrated better postoperative manifest refractive spherical equivalent (MRSE), manifest sphere, and absolute value of the difference in actual and target spherical equivalent refraction (|∆ SEQ|), within the total population, moderate myopia, and low astigmatism groups, but this did not lead to improved postoperative uncorrected distance visual acuity (UDVA) or best corrected distance visual acuity (CDVA). Though astigmatic correction and postoperative angle of error were similar between optical zone sizes, they were significantly worse with high myopia. Overall, this study demonstrates differences in visual outcomes between the 6.0 and 6.5 mm optical zone sizes that may warrant consideration; however, essentially, the results are comparable between them.
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http://dx.doi.org/10.3390/jcm10173776DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8432203PMC
August 2021

Controversy and Consideration of Refractive Surgery in Patients with Heritable Disorders of Connective Tissue.

J Clin Med 2021 Aug 24;10(17). Epub 2021 Aug 24.

Hoopes Vision Research Center, Hoopes Vision, Draper, UT 84020, USA.

Heritable Disorders of Connective Tissue (HDCTs) are syndromes that disrupt connective tissue integrity. They include Osteogenesis Imperfecta (OI), Ehlers Danlos Syndrome (EDS), Marfan Syndrome (MFS), Loeys-Dietz Syndrome (LDS), Epidermolysis Bullosa (EB), Stickler Syndrome (STL), Wagner Syndrome, and Pseudoxanthoma Elasticum (PXE). Because many patients with HDCTs have ocular symptoms, commonly myopia, they will often present to the clinic seeking refractive surgery. Currently, corrective measures are limited, as the FDA contraindicates laser-assisted in-situ keratomileusis (LASIK) in EDS and discourages the procedure in OI and MFS due to a theoretically increased risk of post-LASIK ectasia, poor wound healing, poor refractive predictability, underlying keratoconus, and globe rupture. While these disorders present with a wide range of ocular manifestations that are associated with an increased risk of post-LASIK complications (e.g., thinned corneas, ocular fragility, keratoconus, glaucoma, ectopia lentis, retinal detachment, angioid streaks, and ocular surface disease), their occurrence and severity are highly variable among patients. Therefore, an HDCT diagnosis should not warrant an immediate disqualification for refractive surgery. Patients with minimal ocular manifestations can consider LASIK. In contrast, those with preoperative signs of corneal thinning and ocular fragility may find the combination of collagen cross-linking (CXL) with either photorefractive keratotomy (PRK), small incision lenticule extraction (SMILE) or a phakic intraocular lens (pIOL) implant to be more suitable options. However, evidence of refractive surgery performed on patients with HDCTs is limited, and surgeons must fully inform patients of the unknown risks and complications before proceeding. This paper serves as a guideline for future studies to evaluate refractive surgery outcomes in patients with HDCTs.
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http://dx.doi.org/10.3390/jcm10173769DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8432249PMC
August 2021

Ectasia After Corneal Refractive Surgery: A Systematic Review.

Ophthalmol Ther 2021 Aug 20. Epub 2021 Aug 20.

Hoopes Vision Research Center, Hoopes Vision, 11820 S. State Street Suite #200, Draper, UT, 84020, USA.

Introduction: The incidence of ectasia following refractive surgery is unclear. This review sought to determine the worldwide rates of ectasia after photorefractive keratectomy (PRK), laser-assisted in situ keratomileusis (LASIK), and small incision lenticule extraction (SMILE) based on reports in the literature.

Methods: A systematic review was conducted according to modified Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Publications were identified by a search of eight electronic databases for relevant terms between 1984 and 2021. Patient characteristics and preoperative values including manifest refractive spherical refractive equivalent (MRSE), central corneal thickness (CCT), anterior keratometry, postoperative residual stromal bed (RSB), and percent tissue altered (PTA) were summarized. In addition, annual rates of each refractive surgery were determined, and incidence of post-refractive ectasia for each type was calculated using the number of ectatic eyes identified in the literature.

Results: In total, 57 eyes (70 eyes including those with preoperative risk factors for ectasia) were identified to have post-PRK ectasia, while 1453 eyes (1681 eyes including risk factors) had post-LASIK ectasia, and 11 eyes (19 eyes including risk factors) had post-SMILE ectasia. Cases of refractive surgery performed annually were estimated as 283,920 for PRK, 1,608,880 for LASIK, and 96,750 for SMILE. Reported post-refractive ectasia in eyes without preoperative identifiable risk factors occurred with the following incidences: 20 per 100,000 eyes in PRK, 90 per 100,000 eyes in LASIK, and 11 per 100,000 eyes in SMILE. The rate of ectasia in LASIK was found to be 4.5 times higher than that of PRK.

Conclusion: Post-refractive ectasia occurs at lower rates in eyes undergoing PRK than LASIK. Although SMILE appears to have the lowest rate of ectasia, the number of cases already reported since its recent approval suggests that post-SMILE ectasia may become a concern. Considering that keratoconus is a spectrum of disease, pre-existing keratoconus may play a larger role in postoperative ectasia than previously accounted for in the literature.
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http://dx.doi.org/10.1007/s40123-021-00383-wDOI Listing
August 2021

Five-Year Incidence, Management, and Visual Outcomes of Diffuse Lamellar Keratitis after Femtosecond-Assisted LASIK.

J Clin Med 2021 Jul 11;10(14). Epub 2021 Jul 11.

Hoopes Vision, HDR Research Center, 11820 S. State Street Suite #200, Draper, UT 84020, USA.

Femtosecond (FS) lasers initially had a higher incidence of diffuse lamellar keratitis (DLK) compared with microkeratome flap creation. It has been theorized that higher-frequency lower-energy (HFLE) FS lasers would reduce the incidence of DLK. Our study sought to evaluate the incidence of newer HFLE FS lasers with pulse frequencies above 60 kHz. It was a retrospective case-control study evaluating the incidence of DLK following flap creation with one of three FS lasers (AMO iFs, WaveLight FS200, Zeiss VisuMax). Uncomplicated LASIK cases were included as the control group (14,348 eyes) and cases of DLK were recorded in the study group (637 eyes). Of the 637 cases of DLK, 76 developed stage II, 25 progressed to stage III, and only three developed stage IV DLK. The overall incidence rate of DLK was 4.3%; it has fallen with the invention of newer HFLE FS lasers and is approaching the DLK incidence rates of DLK with microkeratome.
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http://dx.doi.org/10.3390/jcm10143067DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8304683PMC
July 2021

Corneal Donation: Current Guidelines and Future Direction.

Clin Ophthalmol 2021 12;15:2963-2973. Epub 2021 Jul 12.

Hoopes Vision Research Center, Draper, UT, 84020, USA.

Purpose: This review aims to outline current practices and guidelines of corneal donation and eye banking, describes the implications of COVID-19 and emerging diseases on the corneal donor pool, and discusses future trends to improve and increase the efficiency of the processes involved in corneal donation and eye banking.

Summary: Corneal screening, preservation, corneal storage, and prevention of systemic disease transmission from donor to recipient have been crucial in shaping the policies of the FDA and eye banks across the world. Eye banks globally have developed varying guidelines and criteria for evaluating the viability of donor corneas. Variables such as the age of the donor, medical history, and potential disease transmission are important screening parameters. While known infectious diseases may be transmissible through the cornea, emerging infectious diseases that are not well studied may be more transmissible than other infections. In particular, coronavirus has impacted corneal transplantation as SARS-CoV-2 expression has been detected in corneal tissue and conjunctiva. In recent years, partial-thickness corneal transplantations have been introduced. Lamellar grafts and other corneal layers are now utilized for transplantation of the specific areas that are damaged.
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http://dx.doi.org/10.2147/OPTH.S284617DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8285277PMC
July 2021

Toric Implantable Collamer Lens for the Treatment of Myopic Astigmatism.

Clin Ophthalmol 2021 6;15:2893-2906. Epub 2021 Jul 6.

Hoopes Vision Research Center, Hoopes Vision, Draper, UT, 84020, USA.

Purpose: To report visual outcomes following surgical correction of myopic astigmatism with Visian Toric implantable collamer lens (ICL) (STAAR Surgical, Monrovia, CA, USA) at a single tertiary refractive center in the United States.

Patients And Methods: Toric ICL was implanted in 96 eyes (55 patients) with mean preoperative sphere of -8.98 ± 3.04 diopters (D) and cylinder of -2.67 ± 1.02 D from December 2018 to February 2021. Primary visual outcomes of efficacy, safety, stability, predictability of refractive correction, and astigmatic analysis were reported at three and twelve months postoperatively. Secondary subjective outcomes included patient-reported dry eye symptoms and glare/halos at postoperative visits. Other secondary outcomes were biometric data and postoperative vault over time.

Results: At three and twelve months, 75 and 46 eyes were evaluated, respectively. At twelve months, the mean manifest refraction spherical equivalent (MRSE) was -0.23 ± 0.47 D with 93% achieving within ±1.00 D of target refraction. The manifest refractive cylinder (MRC) at twelve months was -0.73 ± 0.51 D, with 86% within ±1.00 D of target. Uncorrected distance visual acuity (UDVA) was 20/20 or better in 74% of eyes at twelve months. No patients lost ≥2 lines of corrected distance visual acuity (CDVA) at twelve months. The mean angle of error was -0.9 ± 10.2° at three months and -1.6 ± 12.8° at twelve months. One patient required bilateral lens rotation, four patients underwent secondary enhancement with LASIK/PRK, and seven patients underwent postoperative limbal relaxing incisions.

Conclusion: This initial single-site experience finds Toric ICL implantation for myopic astigmatism to be safe and effective. Patients can achieve markedly improved UDVA in a single surgery with stable vision over time and minimal adverse subjective symptoms.
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http://dx.doi.org/10.2147/OPTH.S321095DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8274236PMC
July 2021

Incidence, Risk, and Visual Outcomes after Repositioning of Acute Non-Traumatic Flap Dislocations Following Femtosecond-Assisted LASIK.

J Clin Med 2021 Jun 3;10(11). Epub 2021 Jun 3.

Hoopes Vision Research Center, Hoopes Vision, 11820 S. State Street Suite #200, Draper, UT 84020, USA.

Although the use of femtosecond lasers instead of mechanical devices has decreased the incidence of flap complications following laser-assisted in situ keratomileusis (LASIK), dislocations and striae still occur. Flap repositioning is an effective intervention to improve visual outcomes after acute flap complications in both microkeratome-assisted and femtosecond-assisted LASIK. This retrospective case series included patients undergoing flap repositioning secondary to acute flap dislocation and/or visually significant striae within the first two weeks following femtosecond LASIK (FS-LASIK) from 2015 to 2020 at a single institution. Preoperative, intraoperative, and postoperative de-identified data were analyzed for incidence, risk factors, and visual acuity outcomes. The incidence of flap repositioning was 0.35% in 21,536 eyes ( = 70). Indications for repositioning included acute flap dislocation (35.7%) and visually significant striae (64.3%). High myopia (OR = 3.04, = 0.001) and patient age over 50 years (OR = 3.69, = 0.001) were the strongest risk factors for these complications. Prior to flap repositioning, uncorrected distance visual acuity (UDVA) of 20/20 or better and 20/40 or better occurred in 19% and 57% of eyes, respectively. After repositioning, a final UDVA of 20/20 or better and 20/40 or better occurred in 78% and 98% of eyes, respectively. After repositioning, one line of UDVA was lost in two eyes (2.8%) and two lines were lost in one eye (1.4%). Risk factors for acute flap dislocation included high myopia and age over 50 years. Flap repositioning was effective in salvaging visual outcomes.
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http://dx.doi.org/10.3390/jcm10112478DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8199895PMC
June 2021

Anterior Chamber Retained Lens Fragments After Cataract Surgery: A Case Series and Narrative Review.

Clin Ophthalmol 2021 21;15:2625-2633. Epub 2021 Jun 21.

Hoopes Vision Research Center, Hoopes Vision, Draper, UT, USA.

Introduction: Retained lens fragments in the anterior chamber following cataract extraction (CE) with phacoemulsification are rare but can lead to significant patient morbidity. Our study aimed to identify risk factors associated with retained lens fragments.

Methods: Patients who underwent cataract surgery and subsequently identified to have retained lens fragments in the anterior segment were included. Incidence per year, patient demographics, visual acuity, ocular biometrics, surgical technique, surgeon performing CE, and outcomes were collected retrospectively and compared to a control group.

Results: Twenty-four patients were identified with retained lens fragments, with an incidence of 0.10%. The mean age was 76 years ±6.72 (60-80) compared to 63 ±11.41 (22-86) in the control group (p <0.001). Patients with UDVA 20/150 or worse experienced a greater average improvement in visual acuity compared to patients with UDVA better than 20/150 (logMAR 0.46 vs logMAR 0.05). The mean intraocular pressures before (CE), after CE but before fragment removal, and following fragment removal were 14 mmHg ±2.59, 19 mmHg ±8.20, and 11 mmHg ±2.75, respectively. Twenty-two patients presented with inferiorly located fragments. Statistically significant biometrics include mean anterior chamber depth (3.1 mm ±0.37 vs 3.33 mm ±0.39, p = 0.01) and lens thickness (4.77 mm ±0.44 vs 4.35 mm ±0.44, p = <0.001). Yearly incidence rates per surgeon ranged from 0.00% to 0.85%. In 2003 and 2004, one surgeon had significantly higher incidence rates (0.31 and 0.40%) compared to the average combined rate of all surgeons throughout the study (0.10), with p values of 0.001 and 0.003, respectively. The mean number of days between CE and fragment removal was 26 ±40 (1-138).

Conclusion: Increased patient age, shallow anterior chamber depth, and thick lens may be risk factors for retained lens fragments. There may be additional surgeon-specific risk factors. Phacoemulsification technique (Divide-and-Conquer versus Horizontal Chop) showed no significant difference.
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http://dx.doi.org/10.2147/OPTH.S314148DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8232887PMC
June 2021

Neuropathic Corneal Pain Following LASIK Surgery: A Retrospective Case Series.

Ophthalmol Ther 2021 Sep 15;10(3):677-689. Epub 2021 Jun 15.

HDR Research Center, Hoopes Vision, University of Utah Health Sciences Center, 11820 S. State Street Suite #200, Draper, UT, 84020, USA.

Introduction: Transient dry eye symptoms have been reported following laser in situ keratomileusis (LASIK). Very rarely, patients may present with debilitating symptoms of dry eye syndrome (DES) with limited or no evidence of ocular surface disease. These patients are diagnosed with a form of DES known as neuropathic corneal pain (NCP).

Patients And Methods: This study is a retrospective medical record review of a case series of 18 patients who developed NCP post-LASIK over the years 1996-2021. All patients who developed severe ocular pain following LASIK consistent with NCP were included. Patients with severe ocular pain who had evidence of severe ocular surface disease or other ophthalmic etiology to explain their debilitating symptoms were not included.

Results: The average age of patients in our study was 39.5 years. The majority of our patients were female (72.2%) and of Caucasian ancestry (83.3%). The average onset of symptoms was 9.6 months post-LASIK. Patients had past medical histories significant for neuropsychiatric conditions (50%), functional pain syndromes (22.2%), autoimmune diseases (33.3%), and hypothyroidism (27.8%), and the occurrence of these was higher than the national prevalence of these diseases. Symptoms were consistent with the severity and characteristics defining NCP. Treatment was multimodal, involved topical and systemic therapies, and was unique to each patient. Overall, the majority of patients had clinical improvement in symptoms following treatment with regular follow-up.

Conclusion: Although rare, the 26-year prevalence of NCP post-LASIK in our study was roughly 1 in 900 cases. The mean time to onset after surgery was delayed at 9.6 months. Certain risk factors such as neuropsychiatric conditions, history of functional pain syndromes, history of autoimmune conditions, and hypothyroidism may predispose patients to the development of this condition. Patients benefited from proper diagnosis and a multimodal approach to treatment.
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http://dx.doi.org/10.1007/s40123-021-00358-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8319231PMC
September 2021

The impact of vaping on ocular health: a literature review.

Int Ophthalmol 2021 Aug 16;41(8):2925-2932. Epub 2021 Apr 16.

Hoopes Vision Research Center, 11820 State Street Suite #200, Draper, UT, 84020, USA.

Purpose: Vaping, or the use of electronic cigarettes, was initially introduced as a step toward smoking cessation, but has become an increasingly popular option for smokers. Though advertised as safer than conventional cigarettes, these devices have been found to contain carcinogenic chemicals, air pollutants, and heavy metals. The purpose of this article is to shed light on the known effects of vaping on the ocular setting and raise the discussion about additional potential effects that may call for further investigation.

Methods: A comprehensive literature search was conducted for publications pertaining to the effects of vaping on the eye. Relevant studies and findings were summarized in this article.

Results: It was found that aldehydes and free radicals present in electronic cigarettes may induce a disturbance in tear film stability, and vape flavorings may damage the lipid layer through peroxidation. Corneal staining has been shown to appear following exposure to e-cigarette vapor, with nicotine and acrolein potentially inducing an inflammatory response in corneal epithelial cells. In addition, nicotine has been shown to induce nystagmus, exert vasoconstrictive effects on ocular blood flow, and may interfere with retinal light-adapted vision. Vape-related explosions, though unpredictable, may also result in decreased visual acuity along with long-term ocular trauma.

Conclusion: Research discussing both the short-term and long-term effects of vaping on the eye is limited. However, the potential harms of substances such as nicotine and aldehydes warrant additional investigation and increased education about the detriment that electronic cigarettes may inflict on sensitive organs.
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http://dx.doi.org/10.1007/s10792-021-01842-wDOI Listing
August 2021

PRK Enhancement for Residual Refractive Error After Primary PRK: A Retrospective Study.

Ophthalmol Ther 2021 Mar 30;10(1):175-185. Epub 2021 Jan 30.

Hoopes Vision Research Center, Hoopes Vision, Draper, UT, USA.

Introduction: The efficacy and safety of photorefractive keratectomy (PRK) has been well documented, but outcomes of PRK enhancement following PRK remain understudied. This study aimed to evaluate the safety, efficacy, and predictability of PRK enhancement in patients with residual refractive error after primary PRK and compare these results to prior studies as well as Food and Drug Administration (FDA) safety and efficacy clinical endpoints.

Methods: This non-randomized, retrospective chart analysis included eyes with a history of PRK that underwent PRK enhancement at a single center. Post-enhancement data were documented at 3-month and 1-year visits. Patient characteristics between the study group and a control group who underwent primary PRK only were compared. Safety and efficacy measures included change in uncorrected distance visual acuity (UDVA), change in corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), amount of induced astigmatism, and presence of serious adverse events.

Results: A total of 188 eyes from 141 patients were included. When compared to the control group, women underwent PRK enhancement at a higher rate than men (P = 0.004). The group undergoing PRK enhancement had a higher sphere (P = 0.013) and spherical equivalent (P = 0.004) than the control group at the time of primary PRK. MRSE was reduced to - 0.97 ± 0.72 D (- 2.25 to + 2.13 D) from pre-enhancement values of - 0.98 ± 0.66 D (- 2.75 to + 1.75 D) and stable over 12-month visits with 86% and 98% of eyes within ± 0.50 D and ± 1.00 D of target, respectively. UDVA of 20/20 or better was achieved in 75% of eyes. The UDVA of 75% of eyes remained the same or improved by 1 or more Snellen lines compared with pre-enhancement CDVA.

Conclusion: Our results demonstrate that, when compared with previous studies, modern PRK enhancement after PRK has improved visual acuity and refractive outcomes. Though PRK enhancement is not an FDA approved procedure, we show that it meets or exceeds the FDA criteria for the correction of refractive error.
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http://dx.doi.org/10.1007/s40123-021-00331-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7886917PMC
March 2021

Coral Keratitis: Case Report and Review of Mechanisms of Action, Clinical Management and Prognosis of Ocular Exposure to Palytoxin.

Clin Ophthalmol 2021 12;15:141-156. Epub 2021 Jan 12.

Hoopes Vision Research Center, Draper, UT, USA.

Palytoxin is one of the most lethal natural toxins ever discovered. This molecule has been isolated from various marine animals, including zoanthid corals. This popular organism is commonly found in many home saltwater aquariums due to its beauty and survivability. As a result of an increase in popularity, an increased number of individuals are at risk for exposure to this potentially deadly toxin. Affected patients may experience various symptoms based on the route of exposure (ie, cutaneous contact, inhalation of aerosolized toxin, ocular exposure, or ingestion). Ocular exposure can occur in various ways (eg, contact with contaminated water, rubbing the eye with a dirtied hand, or direct spraying into the eye), and incidence rates have dramatically risen in recent years. In this review, we discuss a case of systemic toxicity from inhalation and ocular exposure to presumed palytoxin on a zoanthid coral which resulted in an intensive care unit (ICU) stay, and corneal perforation which required a corneal transplant. Additionally, we review what is known about the mechanism of action of this toxin, propose a comprehensive hypothesis of its effects on corneal cells, and discuss the prognosis and clinical management of patients with systemic symptoms secondary to other routes of exposure.
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http://dx.doi.org/10.2147/OPTH.S290455DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7811479PMC
January 2021

Visual Outcomes After Sequential Posterior Chamber Phakic IOL with Corneal Refractive Surgery (Bioptics) for the Treatment of Myopic Astigmatism.

Clin Ophthalmol 2020 9;14:4337-4346. Epub 2020 Dec 9.

Hoopes Vision Research Center, Hoopes Vision, Draper, UT, USA.

Purpose: To report the outcomes of sequential posterior chamber phakic intraocular lens (PC-pIOL) with corneal refractive surgery in conventional (PC-pIOL prior to refractive surgery) and reverse (refractive surgery prior to PC-pIOL) bioptics for treating high myopic astigmatism.

Setting: Tertiary refractive center, Draper, Utah, USA.

Design: Retrospective case series.

Methods: Medical records of patients who underwent planned bioptics were reviewed. Surgery involved PC-pIOL placement using an implantable collamer lens (ICL) with preceding or subsequent LASIK or PRK. Pre- and postoperative manifest spherical equivalent (SEQ), visual acuity, and PC-pIOL vault were analyzed.

Results: Of the 51 eyes present at 12 months postoperatively, 49 eyes (96%) achieved target SEQ within ±1.00 D and an identical amount achieved refractive astigmatism ≤1.00 D. Post-bioptics eyes achieved a postoperative UDVA equal to or better than preoperative CDVA in 45 eyes (88%). Efficacy and safety indices were 1.08 ± 0.20 (41 eyes) and 1.13 ± 0.22 (44 eyes) for conventional bioptics and 0.99 ± 0.42 (7 eyes) and 1.15 ± 0.38 (7 eyes) for reverse bioptics eyes at 12 months. The maximum PC-pIOL vault of conventional bioptics eyes (27 eyes) within 6 months before and after LASIK/PRK was 385 ± 159 μm and 377 ± 135 μm, respectively (P = 0.71).

Conclusion: Bioptics for high myopic astigmatism was safe and effective. Reverse bioptics, although not as traditional, could provide similar results. Additionally, the PC-pIOL vault does not appear to be affected by LASIK/PRK.
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http://dx.doi.org/10.2147/OPTH.S285140DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7734069PMC
December 2020

Corneal Refractive Surgery in Patients with a History of Herpes Simplex Keratitis: A Narrative Review.

Clin Ophthalmol 2020 16;14:3891-3901. Epub 2020 Nov 16.

Hoopes Vision Research Center, Hoopes Vision, Draper, UT, USA.

The incidence of herpes simplex keratitis (HSK) in patients following corneal refractive surgery is higher than in the general population, and several case reports of ocular morbidity in HSK infection following corneal refractive surgery have been published. HSK is listed by the American Academy of Ophthalmology as a relative contraindication to corneal refractive surgery, although specifics have not been further elucidated. This review summarizes the current literature regarding reactivation of HSK following corneal refractive surgery and provides a guideline for considering corneal refractive surgery in a patient with a previous history of HSK. Based on the current literature, we recommend that corneal refractive surgery is appropriate for patients with a history of HSK without multiple recurrences who have had no evidence of disease for at least one year. In addition to a thorough history and physical examination, we also recommend these patients begin 400 mg twice daily of oral acyclovir or valacyclovir 500 mg once daily for two weeks prior to surgery and continue this regimen for at least two weeks postoperatively or while on topical steroids.
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http://dx.doi.org/10.2147/OPTH.S282070DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7678688PMC
November 2020

Initial Single-Site Experience Using SMILE for the Treatment of Astigmatism in Myopic Eyes and Comparison of Astigmatic Outcomes with Existing Literature.

Clin Ophthalmol 2020 29;14:3551-3562. Epub 2020 Oct 29.

Hoopes Vision Research Center, Hoopes Vision, Draper, UT, USA.

Purpose: To assess a single site's initial experience with SMILE for the treatment of myopic astigmatism and compare outcomes and vector analysis results with the US Food and Drug Administration (FDA) results and published literature.

Patients And Methods: Forty-eight eyes (29 patients) with mean preoperative sphere of -5.11 ± 1.31 diopters (D) and cylinder of -1.12 ± 0.60 D underwent SMILE. Visual acuity, refractive, and vector analysis outcomes as well as subjective measures were reported at three and twelve months postoperatively and compared with FDA results and the published literature between 2014 and 2020 involving treatment of patients with mean cylinders of >-0.50 to ≤-3.00 D.

Results: At three and twelve months, 43 and 32 eyes were evaluated, respectively. At twelve months, mean cylinder power was reduced to -0.38 ± 0.38 D with 78.1% achieving ≤±0.50 D. Uncorrected distance visual acuity (UDVA) ≥20/20 was achieved in 77.4% of eyes by twelve months with 100% achieving ≥20/30 UDVA. No loss of corrected distance visual acuity was observed in eyes seen at twelve months. Correction index (CI) at twelve months was 0.90 indicating overall undercorrection of 10%. Twelve-month CI was 0.96, 0.90, and 0.83 in eyes with preoperative cylinders of <-1.00 D, ≥-1.00 to <-2.00 D, and ≥-2.00 D, respectively. Mean angle of error was -1.58 ± 11.61° ranging from -24.22° to 37.75°.

Conclusion: We found SMILE to be an effective and safe means of achieving spectacle independence and improving visual acuity in patients with myopic astigmatism. SMILE has the potential for improved clinical outcomes with better nomogram guidance and advancements in technique. However, surgeons must be aware of the potential for undercorrection in with-the-rule astigmatism and at higher preoperative cylinders and as well as the potential for overcorrection in against-the-rule and lower preoperative cylinder astigmatism.
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http://dx.doi.org/10.2147/OPTH.S276899DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7607143PMC
October 2020

A Contemporary Risk Analysis of Iatrogenic Transmission of Creutzfeldt-Jakob Disease (CJD) via Corneal Transplantation in the United States.

Ophthalmol Ther 2020 Sep 20;9(3):465-483. Epub 2020 Jun 20.

Hoopes Vision Research Center, Draper, UT, USA.

Background: Creutzfeldt-Jakob disease (CJD) is a rare, fatal, neurodegenerative prion disease potentially transmissible through corneal transplantation. While statistical analyses performed two decades ago estimated the overall prevalence of CJD in the corneal donor pool to be low, the recent significant increase in corneal transplants performed and deaths due to CJD in the U.S. warrants a contemporary risk analysis.

Methods: A literature review was conducted to determine the overall number of globally reported cases of CJD transmission through corneal transplantation. U.S. mortality and cornea donation data were utilized to estimate the age-stratified prevalence of undiagnosed, latent CJD in the cornea donor pool in 2018. A historical statistical analysis was performed to estimate the number of corneas from donors with latent CJD entering the U.S. donor pool for each year between 1979 and 2018. From these statistical analyses, risk factors of iatrogenic transmission were identified and summarized.

Results: Ten reported cases of iatrogenic transmission of CJD through corneal transplants were identified globally. In 2018, an estimated 3.8 corneas from donors with undiagnosed latent CJD potentially entered the pool of 111,703 transplant-intended corneas harvested from individuals aged 31-80. Between 1979 and 2018, an estimated 47 corneas may have entered the U.S. transplant-intended pool from donors with latent CJD aged 35 to 84. The advanced age of donors and a history of multiple transplants in recipients were both prominent risk factors for iatrogenic transmission.

Conclusions: The 10 reported global cases of iatrogenic transmission likely under-represent the number of individuals with a coinciding history of death by CJD and prior corneal transplantation, as supported by our statistical analysis and lack of geographical diversity of reported cases. As effective screening methods develop and globalization of cornea transplantation broadens, it is of utmost importance that cornea transplantation history among victims of CJD should be investigated and reported.
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http://dx.doi.org/10.1007/s40123-020-00272-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7406626PMC
September 2020

Myopic regression and recurrent Salzmann nodule degeneration after laser in situ keratomileusis in Ehlers Danlos Syndrome.

Am J Ophthalmol Case Rep 2020 Sep 4;19:100729. Epub 2020 May 4.

Hoopes Durrie Rivera Research Center, Hoopes Vision; 11820 State St, Draper, UT, 84020, USA.

Purpose: We describe the first case of Ehlers Danlos Syndrome (EDS) reported in the English language ophthalmic literature to have undergone Laser In Situ Keratomileusis (LASIK) surgery.

Observations: We review our patient's specific postoperative complications of myopic regression, Salzmann nodular degeneration, and dry eye syndrome, as well as the risks and consequences of performing LASIK on patients with this collagen disorder.

Conclusions And Importance: Refractive errors may prompt EDS patients to seek laser vision correction, placing them at increased risk for complications such as myopic regression, keratectasia, and dry eye syndrome. Aberrant wound healing and collagen dysfunction may have influenced our patient's myopic regression and Salzmann nodule degeneration post-LASIK. Currently, EDS is considered a relative contraindication in LASIK due to a presumed higher risk of postoperative keratectasia; however, we believe it is possible that not all forms of EDS need to be an absolute contraindication to LASIK. More research is warranted to determine preoperative risk stratification for laser vision surgery in each subtype of EDS.
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http://dx.doi.org/10.1016/j.ajoc.2020.100729DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7225616PMC
September 2020

Risks Posed to Corneal Transplant Recipients by COVID-19-Affected Donors.

Ophthalmol Ther 2020 Sep 6;9(3):371-379. Epub 2020 May 6.

Hoopes Vision Research Center, Draper, UT, USA.

The recent emergence of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its resultant human disease, COVID-19, will likely have a significant impact on the corneal tissue donor pool. Current recommendations from the United States and global eye bank associations call for the outright avoidance of tissues from donors recently infected with or exposed to COVID-19. This conservative recommendation is currently appropriate given the reported ocular sequelae, tear film viral detectability, and transmissibility of COVID-19. However, the rapidly increasing global prevalence and mortality of COVID-19 threatens the tenability of current tissue exclusion guidelines, and may necessitate their relaxation in the near future.
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http://dx.doi.org/10.1007/s40123-020-00254-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7202264PMC
September 2020

Comparison and application of commercially available fibrin sealants in ophthalmology.

Ocul Surf 2020 07 30;18(3):418-426. Epub 2020 Apr 30.

HDR Research Center, Hoopes Vision, Draper, UT, USA.

Fibrin glues carry many advantages over traditional suture as a tissue adhesive and have been increasingly used in a variety of ophthalmic procedures over the past 15 years. Several fibrin sealants are commercially available worldwide, each of which differs slightly in its composition and mechanism of delivery. The focus of our review is to briefly discuss the reported uses of fibrin in ophthalmic surgery and provide a broad overview of the properties associated with each commercially available fibrin sealant.
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http://dx.doi.org/10.1016/j.jtos.2020.04.006DOI Listing
July 2020

Will Tonic Water Stop My Eyelid Twitching?

Clin Ophthalmol 2020 4;14:689-691. Epub 2020 Mar 4.

HDR Research Center, Hoopes Vision, Draper, UT, USA.

Eyelid myokymia, commonly referred to as "eyelid twitching", is a common, benign condition that resolves in most individuals within hours to days; however, chronic cases can persist for several weeks to months, prompting the search for home remedies that may reduce the frequency or duration of symptoms. In this article, we discuss the proposed pathophysiologic mechanism and safety concerns surrounding tonic water as a treatment for eyelid myokymia.
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http://dx.doi.org/10.2147/OPTH.S235895DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7061523PMC
March 2020

A Narrative Review of Microsporidial Infections of the Cornea.

Ophthalmol Ther 2020 Jun 10;9(2):265-278. Epub 2020 Mar 10.

Hoopes Vision Research Center, Draper, UT, USA.

Microsporidia are a rare and commonly misdiagnosed cause of corneal infection, accounting for approximately 0.4% of cases of microbial keratitis in some populations. Ocular microsporidiosis most often presents as either microsporidial keratoconjunctivitis (MKC) or microsporidial stromal keratitis (MSK). Though these two clinical entities exhibit similar symptomology, they are distinguished from one another by the time course for disease progression, findings on slit-lamp examination, and response to medical therapy. This review summarizes the current literature on the etiology and clinical presentation of microsporidial infections of the cornea and highlights ongoing developments in available diagnostic modalities and treatment regimens.
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http://dx.doi.org/10.1007/s40123-020-00243-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7196102PMC
June 2020

Human allograft refractive lenticular implantation for high hyperopiccorrection.

J Cataract Refract Surg 2020 02;46(2):305-311

From the Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine (Moshirfar), Salt Lake City, Utah Lions Eye Bank (Moshirfar), Murray, Hoopes Durrie Rivera Research Center, Hoopes Vision (Moshirfar, Linn, Ronquillo, Hoopes), Draper, Utah, McGovern Medical School, University of Texas Health Science Center (Hopping, Somani, Vaidyanathan, Liu), Houston, Texas, and Virginia Commonwealth University School of Medicine (Barnes), Richmond, USA.

Hyperopia is a common form of refractive error in the United States. Many refractive errors can be treated with refractive surgery methods such as laser in-situ keratomileusis and photorefractive keratectomy; however, in patients with large degrees of hyperopia (≥+5.0 diopters [D]), these surgical methods are limited because of higher rates of refractive regression. Lenticule Intrastromal Keratoplasty (LIKE) is a surgical procedure that can be used to correct refractive errors in patients with high hyperopia. The authors describe the first intrastromal implantation of an allograft lenticule performed for the primary correction of hyperopia in the United States, and demonstrate that LIKE is potentially an effective procedure for the correction of high hyperopia. Mechanisms for achieving the intended refractive correction and the complications our patient experienced, including epithelial ingrowth and flap necrosis, are discussed.
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http://dx.doi.org/10.1097/j.jcrs.0000000000000011DOI Listing
February 2020

Corneal Refractive Surgery in Patients with History of Optic Neuritis.

J Ophthalmic Vis Res 2019 Oct-Dec;14(4):436-441. Epub 2019 Oct 24.

John A. Moran Eye Center, Department of Ophthalmology and Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, USA.

Purpose: The purpose of this study was to evaluate the risk of recurrence of optic neuritis after corneal refractive surgery in patients with a history of optic neuritis and to examine the safety and efficacy of the procedure in this population.

Methods: This was a retrospective chart review of patients with a history of optic neuritis who underwent laser-assisted in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) at a single tertiary center from June 1996 to December 2014. Fifteen eyes of 14 patients were included in this study. Visual acuity before and after the surgery was recorded. Patients were followed-up for over five years postoperatively for the recurrence of optic neuritis.

Results: The average LogMAR best corrected visual acuity (BCVA) preoperatively was 0.12 0.19 (-0.10 to 0.60) and postoperatively was 0.06 0.10 (-0.10 to 0.30). No eyes lost lines of BCVA. The average LogMAR uncorrected distance visual acuity (UDVA) after surgery was 0.12 0.13 (0.00 to 0.48). Twenty-eight percent of patients reached a UDVA of 20/20 or better after refractive surgery. Optic neuritis recurred in 3/15 (20%) eyes and 3/14 patients (21%).

Conclusion: While corneal refractive procedures appear safe in patients with a history of optic neuritis, our data suggest that their efficacy may be reduced.
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http://dx.doi.org/10.18502/jovr.v14i4.5445DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6825689PMC
October 2019

Comparison of FDA-Reported Visual and Refractive Outcomes of the Toric ICL Lens, SMILE, and Topography-Guided LASIK for the Correction of Myopia and Myopic Astigmatism.

J Refract Surg 2019 Nov;35(11):699-706

Purpose: To compare U.S. Food and Drug Administration (FDA)-reported visual and refractive outcomes following surgical correction of myopia and myopic astigmatism using the Visian Toric Implantable Collamer Lens (STAAR Surgical, Monrovia, CA) (Toric ICL), small incision lenticule extraction (SMILE), and topography-guided laser in situ keratomileusis (TG-LASIK).

Methods: FDA summary of safety and effectiveness data (SSED) were analyzed for each of the three platforms. Primary outcomes measured were efficacy, safety, stability, and accuracy of refractive correction. Stratified mean refractive spherical equivalent (MRSE) data were assessed.

Results: One hundred twenty-four Toric ICL patients (210 eyes), 357 SMILE patients (357 eyes), and 212 TG-LASIK patients (249 eyes) were included. SMILE eyes had a significant improvement in postoperative uncorrected distance visual acuity with respect to preoperative corrected distance visual acuity from 3 to 12 months (P < .001), whereas TG-LASIK had no further improvement from 3 to 12 months (P = .79). For preoperative MRSE greater than 10.00 diopters (D), there was a significant difference in the percentage of eyes achieving postoperative MSRE within ±0.50 D between Toric ICL (66%) and SMILE (100%) (P < .001). SMILE was consistently more accurate than Toric ICL for cylinder within ±0.25 D (P < .001), ±0.50 D (P < .001), and ±1.00 D (P = .0014).

Conclusions: All three platforms analyzed in this study had excellent efficacy, safety, stability, and accuracy. Stratified analysis revealed that SMILE may be comparable to Toric ICL for patients with high myopia or myopic astigmatism, and SMILE may have a longer visual recovery compared to TG-LASIK than previously indicated. [J Refract Surg. 2019;35(11):699-706.].
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http://dx.doi.org/10.3928/1081597X-20190930-01DOI Listing
November 2019

Management of cataract in the setting of uveitis: a review of the current literature.

Curr Opin Ophthalmol 2020 Jan;31(1):3-9

Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake Utah Lions Eye Bank, Murray Hoopes Durrie Rivera Research Center, Hoopes Vision, Draper, Utah McGovern Medical School at the University of Texas Health Science Center at Houston, Houston, Texas The University of Arizona College of Medicine-Tucson, Tucson, Arizona, USA.

Purpose Of Review: This review aims to cover the preoperative planning, intraoperative considerations, and postoperative management that aids in successful outcomes of patients with cataract and uveitis. Disease-specific management and pediatric management will also be addressed.

Recent Findings: Dexamethasone implants appear to be a safe and effective addition to standard steroid treatment in decreasing the incidence of postoperative cystoid macular edema (CME). Intravitreal steroids and topical difluprednate have shown utility in CME treatment.

Summary: Cataract surgery in eyes with uveitis is generally safe and effective if inflammation is well controlled; however, complication rates are still higher than in eyes without uveitis. Future investigations should delineate outcomes for eyes with different etiologies of uveitis, and further research is needed to adequately control inflammation and avoid postoperative complications.
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http://dx.doi.org/10.1097/ICU.0000000000000626DOI Listing
January 2020

Pressure-Induced Interlamellar Stromal Keratitis After Small-Incision Lenticule Extraction Procedure: A Case Report.

Cornea 2020 Feb;39(2):254-257

Hoopes Durrie Rivera Research Center, Hoopes Vision, Draper, UT; and.

Purpose: To report a case of pressure-induced interlamellar stromal keratitis (PISK) after small-incision lenticule extraction (SMILE) for the correction of myopic astigmatism in the United States.

Methods: We report the case of a 27-year-old man who underwent uneventful SMILE surgery and presented with pressure-induced stromal keratitis. Anterior and posterior segment examination, uncorrected distance visual acuity, refraction, intraocular pressure, and pachymetry values are reported from this time period.

Results: Three weeks postoperatively, examination revealed new-onset central corneal haze and edema in both eyes, more significant in the right eye. The patient was given a presumptive diagnosis of diffuse lamellar keratitis. Intensive corticosteroid treatment was administered, causing a significant decline in uncorrected distance visual acuity OD from 20/25 to 20/250 and OS from 20/20 to 20/60, with a significant myopic shift of -3.0 D and -1.0 D, respectively. In our case, pachymetry measurements revealed 78 μm OD and 43 μm OS of additional corneal thickness. Pressure readings were 25 mm Hg OD and 19 mm Hg OS, respectively. He was diagnosed with PISK, and after 4 days of steroid discontinuation and Brimonidine-Timolol administration, his symptoms had improved with resolution of corneal edema.

Conclusions: Clinicians should be aware that PISK is a potential complication of SMILE. Postoperative intraocular pressure measurements are an important aspect of the management of postcorneal refractive surgery patients because the differentiation of PISK from diffuse lamellar keratitis, as well as the early detection and treatment of PISK, can avoid severe complications.
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http://dx.doi.org/10.1097/ICO.0000000000002196DOI Listing
February 2020

Keratoconus in a patient with Alport syndrome: A case report.

World J Clin Cases 2019 Oct;7(19):3012-3017

Hoopes Durrie Rivera Research Center, Hoopes Vision, Draper, UT 84020, United States.

Background: Known ocular manifestations of Alport syndrome include features such as anterior lenticonus and fleck retinopathy. Reports of keratoconus in such patients are limited. We report tomographic findings consistent with keratoconus in a patient with Alport syndrome.

Case Summary: A 52-year-old female was referred to our ophthalmology clinic with decreased vision and increased tearing. She was diagnosed with stage III Alport syndrome two years prior. Upon examination she was found to have average keratometries of 48 D bilaterally with tomographic evidence of keratoconus.

Conclusion: Although a rare presentation, concurrent Alport syndrome and keratoconus should be considered when reviewing the ocular health of Alport syndrome patients and appropriate management steps should be taken upon the diagnosis.
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http://dx.doi.org/10.12998/wjcc.v7.i19.3012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6795741PMC
October 2019

Delayed-Onset Transient Light Sensitivity Syndrome after Corneal Collagen Cross-Linking: A Case Series.

Med Hypothesis Discov Innov Ophthalmol 2019 ;8(3):250-256

Hoopes Durrie Rivera Research Center, Hoopes Vision, Draper, UT, USA.

In this case series, we report a potentially novel association of corneal collagen crosslinking (CCL) with the development of photophobia symptoms in a series of patients at a tertiary ophthalmology clinic and describe their clinical course. Photosensitivity is a rare and seemingly unpredictable complication of refractive surgery but can present as a disabling, bilateral ocular pain that requires immediate treatment. This complication, termed transient light-sensitivity syndrome (TLSS), can have a substantially delayed presentation after ocular procedures and is associated with inflammation of structures in the anterior chamber that can be imperceptible on slit-lamp examination. Traditionally, exposure to high-energy femtosecond lasers is hypothesized to create stromal gas bubbles powering postoperative inflammatory reactions. TLSS-like symptoms after CCL may be due to a secondary inflammatory response involving activated keratocytes and cytokine release. However, free radical damage from the interaction of riboflavin and ultraviolet in CCL may also drive this inflammatory process.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6778466PMC
January 2019

Comparative Analysis of LASIK Flap Diameter and its Centration Using Two Different Femtosecond Lasers.

Med Hypothesis Discov Innov Ophthalmol 2019 ;8(3):241-249

HDR Research Center, Hoopes Vision, Draper, UT, USA.

The aim of this study was to compare the diameter, accuracy, variability, and centration with respect to the limbus of corneal flaps created by two femtosecond lasers, the VisuMax, and Wavelight FS200, for laser in situ keratomileusis (LASIK) and how these flaps affect visual outcomes. This is a retrospective chart review of flap morphology created during LASIK Surgery. Overall, 168 eyes underwent flap creation using the WaveLight FS200 laser, and on 189 eyes, the VisuMax laser was used. Of these total number, flap morphology was analyzed in a random sample of 158 eyes; 80 with the Visumax laser and 78 with the WaveLight FS200 laser. Intraoperative photos of the flaps taken by the Wavelight Allegretto EX500 were analyzed. Flap diameters and centration were measured using Adobe Acrobat Pro. All patients had visual acuity measurements including uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical equivalent refraction (SE) and refractive astigmatism recorded three months postoperatively. Greater than 90% of patients in both groups achieved a UDVA of 20/20 postoperatively. The mean difference between targeted and achieved flap diameter was 0.50 +/- 0.15 mm in the VisuMax group and 0.35 +/- 0.15 millimeters (mm) in the FS200 group (<0.01). The flap diameters of the VisuMax group were more precise with a variance of 0.024 mm compared to a variance of 0.038 mm in the FS200 group (<0.05). VisuMax flaps were more nasally displaced (log(N/T) = -0.21 +/- 0.10 mm) compared to the FS200 flaps (log(N/T) = 0.03 +/- 0.10 mm), (< 0.01). We concluded that both the VisuMax and FS200 created flaps larger than the preoperative targeted diameter. VisuMax created corneal flaps that had a greater degree of deviation from the targeted diameter when compared to flaps from the FS200. However, there was less variance in the VisuMax flap diameter. In addition, VisuMax flaps were more nasally displaced. There were no statistically significant differences in visual outcomes when comparing the two femtosecond lasers.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6778470PMC
January 2019

Advances in Biomechanical Parameters for Screening of Refractive Surgery Candidates: A Review of the Literature, Part III.

Med Hypothesis Discov Innov Ophthalmol 2019 ;8(3):219-240

HDR Research Center, Hoopes Vision, Draper, UT, USA.

Corneal biomechanical properties have garnered significant interest in their relation to the development of ectatic corneal disease. Alongside the advent of corneal tomography and Scheimpflug imaging such as Pentacam and Galilei, there have been advances in assessing the cornea based on its biomechanical characteristics. Though the aforementioned imaging systems are highly capable of identifying morphologic abnormalities, they cannot assess mechanical stability of the cornea. This article, in contrast to Parts I and II of this article series, will focus on in vivo corneal biomechanical imaging systems. The two most readily available commercial systems include the Corvis ST and the Ocular Response Analyzer. Both of these systems aimed to characterize corneal biomechanics via distinct measurements. While in Parts I and II of this article series the authors focused on elevation, pachymetric, and keratometric data, the purpose of this article was to summarize biomechanical parameters and their clinical use in screening refractive surgery candidates. Moreover, this article explores biomechanical decompensation and its role in the development of corneal ectasia and keratoconus. There is a focus on the diagnostic accuracy of biomechanical indices in the identification of diseases such as keratoconus that may preclude a patient from undergoing refractive surgery.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6778467PMC
January 2019
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