Transepithelial phototherapeutic keratectomy for treatment-resistant recurrent corneal erosion syndrome.

BACKGROUND: To evaluate the efficacy and safety of trans-epithelial phototherapeutic keratectomy (TE-PTK) as a treatment for recurrent corneal erosion syndrome (RCES) in patients with symptoms refractory to conventional treatments. METHODS: All patients who received TE-PTK treatment for RCES had failed 3 or more conventional treatments and were reviewed, and if met criteria, approved by healthcare workers of the British Columbia public health authority (Medical Services Plan (MSP). A retrospective chart review and telephone survey were conducted at the Pacific Laser Eye Centre (PLEC). Exclusion criteria were ocular co-morbidities potentially affecting treatment efficacy. RESULTS: This study included 593 eyes of 555 patients (46.2% male; 50.9 ± 14.2 years old) who underwent TE-PTK. The leading identified causes of RCES were trauma (45.7%) and anterior basement membrane dystrophy (44.2%). The most common pre-PTK interventions were ocular lubricants (90.9%), hypertonic solutions (77.9%), and bandage contact lenses (50.9%). Thirty-six eyes had undergone surgical interventions such as stromal puncture, epithelial debridement, or diamond burr polishing. Post-PTK, 78% of patients did not require any subsequent therapies and 20% required ongoing drops. Six patients (1.1%) reported no symptom improvement and required repeat TE-PTK for ongoing RCES symptoms after initial TE-PTK. All 6 eyes were successfully retreated with TE-PTK (average time to retreatment was 11.3 ± 14.9 months). There was no significant difference in best corrected visual acuity pre- vs. post-operatively. The mean post-operative follow-up was 60.5 months (range: 5-127 months). CONCLUSION: TE-PTK has a good efficacy and safety profile for treatment-resistant RCES. The third-party public health-reviewed nature of this study, the low recurrence rate of RCES, and the low PTK retreatment rate suggest that TE-PTK might be considered for wider use in the management of RCES.

Limbal stem cell deficiency secondary to systemic paclitaxel (Taxol) for breast cancer: a case report.

BACKGROUND: Paclitaxel (PTX) is an antineoplastic drug widely used in treatments for ovarian, breast, and small-cell lung cancer. Although ocular effects associated with PTX have been previously described, very few studies have specifically reported systemic PTX as a contributing factor for limbal stem cell deficiency (LSCD), which is characterized by the loss of stem cell and barrier function of the limbus leading to progressive pain and reduction in visual acuity. Described here is a unique case where a patient was diagnosed with LSCD secondary to PTX use for the treatment of breast cancer, at doses of PTX far lower than what is reported in current literature. CASE PRESENTATION: A 73-year-old woman with a previous diagnosis of breast cancer with liver metastasis presented with a complaint of increasing pain in the left eye more than the right, along with decreasing visual acuity in both eyes following 3 months of PTX therapy for recurrent liver metastases. Upon examination, best-corrected visual acuity was 20/100 in the right eye and counting fingers on the left. Peripheral neovascularization, stromal scarring, and features of limbal stem cell deficiency (LSCD) were noted on the right cornea. A central neurotrophic ulcer with thinning to 50% and 360 degrees of conjunctivalization were noted on the left. After the discontinuation PTX with doxorubicin as the substitute, there was no further progression of her LSCD, and stabilization of her ocular surface was achieved. CONCLUSION: Although chemotherapy induced LSCD is a relatively rare adverse event, it is essential for clinicians starting new chemotherapy agents to consider the potential ocular toxicities that may result in their use. Ophthalmology review is recommended for patients after starting PTX therapy to assess for signs of LSCD, particularly in patients where drug toxicity can be aggravated due to impaired hepatic function.

Correction of Moderate to High Myopia with a Foldable, Angle-Supported Phakic Intraocular Lens: Results from a 5-Year Open-Label Trial.

PURPOSE: To evaluate the 5-year efficacy of a foldable, hydrophobic, angle-supported phakic intraocular lens (pIOL) when used to correct moderate to high myopia. DESIGN: Prospective, nonrandomized, multicenter, open-label cohort study conducted in the United States, the European Union, and Canada (3 separate protocols). PARTICIPANTS: This was a pooled analysis of 515 eyes from 360 patients 18 to 49 years of age with moderate to high myopia (preoperative corrected distance visual acuity [CDVA] ≤0.34 logarithm of the minimum angle of resolution [logMAR]) and with variance in the manifest refraction spherical equivalent within ±0.5 diopter (D) for a minimum of 12 months. INTERVENTION: Implantation of the AcrySof Cachet angle-supported anterior chamber pIOL (Alcon Laboratories, Inc., Fort Worth, TX). MAIN OUTCOME MEASURES: Uncorrected distance visual acuity (UDVA), CDVA, predictability and stability of manifest refraction spherical equivalent (MRSE), serious adverse events, endothelial cell density, and patient satisfaction. RESULTS: Of 360 patients who received implantation in at least 1 eye (515 eyes), 326 (90.6%) completed the study (5-year best-corrected visual acuity data available for 415 eyes). At 5 years, a decrease in CDVA of 2 lines or more was observed in 0.5% of eyes (n = 2/415) compared with preoperative baseline. At 5 years, all 415 eyes achieved a CDVA of 0.34 logMAR or less; 91.3% (n = 379/415) had a CDVA of 0.04 logMAR or less. Mean UDVA ± standard deviation (SD) was 0.01±0.18 logMAR; 94.7% (n = 393/415) and 66.3% (n = 275/415) of eyes had a UDVA of 0.34 logMAR or less or 0.04 logMAR or less, respectively, at 5 years. Mean MRSE ± SD was -0.34±0.57 D (range,-2.50 to 1.63 D). Most eyes (89.8%; n = 371/413) had an MRSE within ±1.00 D of their target refractive error at 5 years and 67.3% (n = 278/413) were within ±0.50 D. Mean annualized central endothelial cell loss was 1.46% (90% confidence interval [CI], -1.6% to -1.3%) from 6 months to 5 years. The most common pIOL-related serious adverse event was adhesion between the cornea and the iris (synechia; n = 24). Most patients (98.1%) indicated that they would have the same pIOL implanted again. CONCLUSIONS: In patients with moderate to high myopia, the AcrySof Cachet angle-supported pIOL provided excellent refractive correction for up to 5 years after implantation, with a low rate of mean central endothelial cell loss. Careful patient selection is necessary to achieve optimal postsurgical outcomes.

Characterization of polymer adsorption onto drug nanoparticles using depletion measurements and small-angle neutron scattering.

Production of polymer and/or surfactant-coated crystalline nanoparticles of water-insoluble drugs (nanosuspensions) using wet bead milling is an important formulation approach to improve the bioavailability of said compounds. Despite the fact that there are a number of nanosuspensions on the market, there is still a deficiency in the characterization of these nanoparticles where further understanding may lead to the rational selection of polymer/surfactant. To this end small-angle neutron scattering (SANS) measurements were performed on drug nanoparticles milled in the presence of a range of polymers of varying molecular weight. Isotopic substitution of the aqueous solvent to match the scattering length density of the drug nanoparticles (i.e., the technique of contrast matching) meant that neutron scattering resulted only from the adsorbed polymer layer. The layer thickness and amount of hydroxypropylcellulose adsorbed on nabumetone nanoparticles derived from fitting the SANS data to both model-independent and model dependent volume fraction profiles were insensitive to polymer molecular weight over the range Mv = 47-112 kg/mol, indicating that the adsorbed layer is relatively flat but with tails extending up to approximately 23 nm. The constancy of the absorbed amount is in agreement with the adsorption isotherm determined by measuring polymer depletion from solution in the presence of the nanoparticles. Insensitivity to polymer molecular weight was similarly determined using SANS measurements of nabumetone or halofantrine nanoparticles stabilized with hydroxypropylmethylcellulose or poly(vinylpyrrolidone). Additionally SANS studies revealed the amount adsorbed, and the thickness of the polymer layer was dependent on both the nature of the polymer and drug particle surface. The insensitivity of the adsorbed polymer layer to polymer molecular weight has important implications for the production of nanoparticles, suggesting that lower molecular weight polymers should be used when preparing nanoparticles by wet bead milling since nanoparticle formation is more rapid but with no likely consequence on the resultant physical stability of the nanoparticles.

Topography-guided laser refractive surgery.

PURPOSE OF REVIEW: Topography-guided laser refractive surgery regularizes the front corneal surface irregularities to achieve the desired refractive outcome. This is particularly applicable in highly aberrated corneas, where wavefront aberrometry is often not possible. This article aims to review the recently published results of topography-guided ablations in normal regular corneas, highly aberrated corneas, and its application in conjunction with collagen cross-linking (CXL) in cases of keratectasia. RECENT FINDINGS: Topography-guided laser ablation is increasingly used with good efficacy and safety outcomes in highly aberrated corneas with irregular astigmatism. These include eyes with refractive surgery complications including postlaser in-situ keratomileusis ectasia, decentered ablation, small optical zones, asymmetrical astigmatism, and postradial keratectomy astigmatism. Further indications are for postkeratoplasty astigmatism and keratoconus. Simultaneous topography-guided ablations with CXL in keratectasia have been promising, both in addressing the surface irregularities and progressive nature of the conditions. SUMMARY: Topography-guided laser refractive surgery is proving to be effective and well tolerated in the visual rehabilitation of highly aberrated eyes, with increasing predictability based on the recent research.

Characteristics of an Acanthamoeba keratitis outbreak in British Columbia between 2003 and 2007.

OBJECTIVE: Quantify and describe Acanthamoeba keratitis (AK) cases in British Columbia (BC). DESIGN: A comparison of annual incidence rates confirms the presence of an outbreak. A case series describes characteristics of the outbreak. PARTICIPANTS: All laboratory-confirmed AK cases (persons) in BC (1988-2011; n = 68) were included in the incidence rate comparison. Of the 42 cases (persons) between 2003 and 2007, 32 were selected to interview (laboratory confirmed, 2005-2007), and the 23 who completed interviews form the case series. METHODS: A comparison of standardized annual incidence rates in historic to outbreak periods is performed by z-score test. A telephone interview and descriptive analysis detailing demographics, risk factors, and contact lens (CL) wearing habits was completed for 23 cases. MAIN OUTCOME MEASURES: We measure number of laboratory confirmed cases in BC. In addition, risk factors and potential exposures of these cases are reported. RESULTS: The annual incidence of AK increased significantly from 0.029 to 0.200 per 100 000 population between historic years (1988-2002) and outbreak years (2003-2007; P = 0.022). The annual incidence of AK has since returned to near historic levels (0.056/100 000 population). The case series identified multiple risk factors, including the use of a specific recalled solution (60.9%), daily soft CL wear (95.7%), all-in-one solutions (95.7%), showering while wearing CL (65.2%), and generally poor CL hygiene. CONCLUSIONS: A significant increase in annual AK incidence occurred between 2003 and 2007 in BC. After 2007, the incidence of AK returned to near historic levels. The recalled solution was associated with many cases; however, other risk factors were also identified, including being unaware of the recall and poor CL hygiene practices, highlighting the need for improved education about the severity of AK and consequences of improper CL hygiene. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Clinical results of topography-based customized ablations in highly aberrated eyes and keratoconus/ectasia with cross-linking.

PURPOSE: To report results of a series of highly aberrated corneas treated with a topography-guided excimer laser ablation. METHODS: Retrospective, nonrandomized, consecutive series of eyes treated with topography-guided photorefractive keratectomy (TG-PRK) with the customized topographical neutralization technique (TNT). Cases included postoperative refractive surgery decentered ablations, optical zone enlargement, asymmetrical astigmatism, postoperative radial keratotomy (RK), postoperative keratoplasty, keratoconus combined with collagen cross-linking (CXL), and postoperative LASIK ectasia combined with CXL. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and manifest refraction were analyzed preoperatively and 6 months postoperatively. RESULTS: In decentered ablation cases, 94% of 37 eyes were within 1.00 diopter (D) of the attempted refractive outcome, with 76% within 0.50 D. Mean topographic, central, optical zone of uniform (monodioptric) power increased from 3.5 to 5.2 mm in 25 eyes. Thirty-one eyes treated for asymmetrical astigmatism showed improvement in cylinder from mean 1.31 to 0.52 D. Ten of 11 eyes treated for previous RK astigmatism achieved postoperative UDVA 20/40 or better. Twenty-seven eyes with postoperative keratoplasty astigmatism were treated, with 7 (25.9%) eyes gaining > or = 2 lines and 12 (44.4%) eyes gaining > or = 1 line of CDVA. Of eyes with keratoconus that were treated using TG-PRK with CXL, 42 (58%) eyes had UDVA 20/40 or better, and 66 (92%) eyes had CDVA 20/40 or better. Twelve (71%) of 17 eyes treated for postoperative LASIK ectasia using TG-PRK with CXL had UDVA 20/40 or better. Nine (53%) eyes gained > or = 2 lines of CDVA. CONCLUSIONS: Topography-guided laser treatment with custom TNT, combined with CXL in keratoconus and ectasia, is an effective, safe, and increasingly predictable option for highly aberrated corneas.

Treatment of corneal defects with delayed re-epithelization with a medical device/drug delivery system for epidermal growth factor.

BACKGROUND: Human recombinant epidermal growth factor has been shown to be effective in corneal healing when applied topically. The purpose of this preliminary study was to observe whether re-epithelization occurred in patients with non-healing corneal defects treated with a bandage contact lenses impregnated with epidermal growth factor. DESIGN: Prospective non-comparative interventional case series study. Epidermal growth factor-impregnated bandage contact lenses (created through passive transfer of epidermal growth factor into hydrogel contact lenses of high water content) were used to passively release epidermal growth factor to the corneal surface of the damaged eye. PARTICIPANTS: Nine clinical patients who presented for tertiary care at the University of British Columbia Eye Care Centre at Vancouver General Hospital. METHODS: All patients had clinically significant delayed corneal re-epithelization that had not healed despite standard treatments including conventional bandage contact lenses and topical medications. Causes of delayed re-epithelization varied from corneal injuries (e.g. alkali burns, recurrent corneal erosions) to recent corneal surgery (photorefractive keratectomy, phototherapeutic keratectomy, penetrating keratoplasty). MAIN OUTCOME MEASURES: Closure of wounds. RESULTS: Re-epithelialization was seen in the corneas of seven of the nine patients within 8 days after insertion of the epidermal growth factor-treated bandage contact lens into the damaged eye. The drug delivery system appeared to be most effective in non-inflamed corneas. CONCLUSIONS: Preliminary results indicate that bandage contact lenses impregnated with epidermal growth factor may be helpful in promoting re-epithelization in corneas with delayed healing. Efficacy appears to be reduced for vascularized and significantly inflamed corneas.

Smoke Gets in the Eye: A systematic review of case reports of ocular complications of crack cocaine use.

ISSUES: Use of crack cocaine and associated medical complications persists globally. Some reports in medical literature describe a sight-threatening condition commonly referred to as 'crack eye' or 'crack eye syndrome'. The purpose of this review is to describe what is known about crack eye from case reports in peer-reviewed literature. APPROACH: A structured search was completed in MEDLINE, TOXLINE, EMBASE, PsychInfo, Scopus and Biomed Central, to collect case reports and case series on corneal complications attributed to crack cocaine smoking. KEY FINDINGS: Of 111 articles screened, 11 contained case reports or series. Thirty individual cases of 'crack eye' were reported. The majority (63%) of cases had bilateral involvement; 83% of all cases with microbial culture results had corneal infections. Aggressive treatment caused an improvement in 95% of all cases and 23% of all cases were lost to follow up. Of those who received treatment for corneal complications associated with crack cocaine, 22% remained with significant visual impairment (hand motions only) in the affected eye. IMPLICATIONS: Clinicians should consider crack cocaine involvement in patients presenting with corneal disease without known predisposing factors, and elicit comprehensive drug histories to prevent a reduction in visual acuity. CONCLUSION: Corneal complications of crack cocaine smoking are caused by a number of synergistic factors, including direct toxicity of crack cocaine vapours to surface cells, impairment of neurogenic support to corneal epithelial integrity, desiccation of the eye surface due to diminished blinking reflex, low level chemical burns and mechanical denudement of surface cells through eye rubbing.

Local anaesthesia as a standard of care for penetrating keratoplasty?

BACKGROUND/OBJECTIVES: To determine preferences in the use of local anaesthesia (LA) versus general anaesthesia (GA) for penetrating keratoplasty (PK), and to examine the safety of LA for PK. SUBJECTS/METHODS: A retrospective analysis of PKs performed at an ophthalmology department in Canada from 01/01/2008 to 01/01/2020 was conducted to investigate rate of major complications. A questionnaire was also sent out to cornea specialists in the United Kingdom (UK) and Canada to determine trends in anaesthesia use for PK. Data on anaesthesia use in keratoplasty data was also obtained from the National Health Service Blood and Tissue (NHSBT) register. RESULTS: The retrospective study found that 2143 PKs were performed under LA by 4 surgeons. The following complications were revealed: 1 acute anxiety attack with tachycardia, 3 extraocular myotoxicity cases requiring squint surgery, 1 expulsive suprachoroidal haemorrhage and 1 retrobulbar haemorrhage. The survey revealed 92% of cornea specialists in Canada preferred LA to GA. In the UK, 4.5% of specialists preferred LA, with most preferring GA due to suprachoroidal haemorrhage risk. NHSBT data revealed that 86.6% of 6181 PKs performed in UK between 01/04/2015 and 31/03/2020 were done under GA. CONCLUSIONS: LA is preferred for PK in Canada, in contrast to the UK where GA is preferred. Our retrospective study suggests a low incidence of LA-related complications. We suggest that LA should be considered for most cornea transplant techniques, including optical penetrating keratoplasty. Rising worldwide keratoplasty numbers, ageing populations and risks of pandemics (e.g. COVID-19) give more reason for reduced reliance on GA.

Intraocular lens power calculations after myopic laser refractive surgery: a comparison of methods in 173 eyes.

PURPOSE: To evaluate and compare published methods of intraocular lens (IOL) power calculation after myopic laser refractive surgery in a large, multi-surgeon study. DESIGN: Retrospective case series. PARTICIPANTS: A total of 173 eyes of 117 patients who had uneventful LASIK (89) or photorefractive keratectomy (84) for myopia and subsequent cataract surgery. METHODS: Data were collected from primary sources in patient charts. The Clinical History Method (vertex corrected to the corneal plane), the Aramberri Double-K, the Latkany Flat-K, the Feiz and Mannis, the R-Factor, the Corneal Bypass, the Masket (2006), the Haigis-L, and the Shammas.cd postrefractive adjustment methods were evaluated in conjunction with third- and fourth-generation optical vergence formulas, as appropriate. Intraocular lens power required for emmetropia was back-calculated using stable post-cataract surgery manifest refraction and implanted IOL power, and then formula accuracy was compared. MAIN OUTCOME MEASURES: Prediction error arithmetic mean ± standard deviation (SD), range (minimum and maximum), and percent within 0 to -1.0 diopters (D), ±0.5 D, ±1.0 D, and ±2.0 D relative to target refraction. RESULTS: The top 5 corneal power adjustment techniques and formula combinations in terms of mean prediction errors, standard deviations, and minimizing hyperopic "refractive surprises" were the Masket with the Hoffer Q formula, the Shammas.cd with the Shammas-PL formula, the Haigis-L, the Clinical History Method with the Hoffer Q, and the Latkany Flat-K with the SRK/T with mean arithmetic prediction errors and standard deviations of -0.18±0.87 D, -0.10±1.02 D, -0.26±1.13 D, -0.27±1.04 D, and -0.37±0.91 D, respectively. CONCLUSIONS: By using these methods, 70% to 85% of eyes could achieve visual outcomes within 1.0 D of target refraction. The Shammas and the Haigis-L methods have the advantage of not requiring potentially inaccurate historical information.

Giant cell arteritis presenting with bilateral loss of vision and jaw pain: reminder of a potentially devastating condition.

A case of giant cell arteritis was diagnosed in a woman who presented with bilateral loss of vision that did not improve with intravenous corticosteroid therapy. Preceding her vision loss, the patient had other symptoms consistent with this diagnosis, notably significant jaw pain and arthralgias. The diverse symptoms of giant cell arteritis are discussed, along with the features that can be used to distinguish jaw pain associated with this condition from the pain of temporomandibular joint pathology. An increased awareness of giant cell arteritis should lead to earlier diagnosis and treatment and avoidance of the devastating consequences of this condition.

New treatment algorithm for keratoconus and cataract: small-aperture IOL insertion with sequential topography-guided photorefractive keratectomy and simultaneous accelerated corneal crosslinking.

PURPOSE: To describe a new treatment algorithm aimed at optimizing refractive outcomes for patients with keratoconus and cataract. SETTING: Private practice in Sydney, Australia. DESIGN: Retrospective case series. METHODS: This procedural approach involves cataract extraction with small-aperture intraocular lens (IOL) insertion, IC-8 IOL (AcuFocus, Inc.), followed by topography-guided photorefractive keratectomy (T-PRK) with simultaneous corneal crosslinking (CXL). Cataract surgery was performed with an initial 2.4 mm clear corneal incision enlarged to 3.5 mm to accommodate IC-8 IOL insertion. Once eyes demonstrated stable corneal tomography and refraction, T-PRK was performed using Schwind excimer laser (500 Hz) with the Vancouver custom topographical neutralization technique, aiming to achieve low myopia. CXL was performed immediately after T-PRK using Optolink hypotonic riboflavin with LIGHTLink-CXL (Lightmed) with 5.4 J total energy delivered at an 18 mw/cm2 irradiance. RESULTS: Outcomes of 4 eyes are reported with all achieving rigid gas-permeable (RGP) contact lens independence, improved corrected distance visual acuity (CDVA) and uncorrected distance visual acuity (UDVA), and regularization of corneal curvature with cone reduction. The mean CDVA improved from 0.43 preoperatively to 0.07 postoperatively (P = .00), and the mean UDVA improved from 0.81 preoperatively to 0.29 postoperatively (P = .04). Postoperative UNVA ranged from N.8 to N.12. CONCLUSIONS: This treatment algorithm demonstrates unique combination of existing corneal and cataract surgical procedures to achieve satisfactory refractive outcomes and RGP contact lens independence in patients with keratoconus and cataract.

Incidence and Outcomes of Cystoid Macular Edema after Descemet Membrane Endothelial Keratoplasty (DMEK) and DMEK Combined with Cataract Surgery.

PURPOSE: To investigate the incidence and outcomes of cystoid macular edema (CME) after Descemet membrane endothelial keratoplasty (DMEK) alone and DMEK combined with cataract surgery (DMEK triple). MATERIALS AND METHODS: A retrospective chart review was performed for patients who underwent DMEK and DMEK triple between January 2014 and March 2018 at two tertiary hospitals. Patients with minimum of 6 months of follow-up were included. Logistic regression analysis was used to identify potential risk factors for CME including gender, age, glaucoma, uveitis, epiretinal membrane, diabetes mellitus, iridotomy, and rebubbling. RESULTS: 09 eyes of 193 patients who underwent DMEK (124 eyes) and DMEK triple (85 eyes) were included. The 6-month incidence of CME was 3.8% (8/209) for all cases, 2.4% (2/85) for DMEK triple, and 4.8% (6/124) for DMEK alone. CME was treated with topical prednisolone acetate 1% and nepafenac four times daily, and/or periocular triamcinolone acetonide, with resolution in all cases. On average, CME was detected 8.9 ± 2.1 weeks postoperatively, with a mean time to resolution of 4.1 ± 1.7 months. The 6-month best-corrected distance visual acuity of eyes that developed CME was not significantly different compared to eyes that did not develop CME (0.17 ± 0.15 logMAR vs. 0.23 ± 0.27 logMAR; p = .76). On logistic regression analysis, no risk factors for developing CME were identified. CONCLUSIONS: The incidence of CME after DMEK was low and not associated with decreased long-term visual acuity. Most cases of CME occurred between 1 and 3 months postoperatively. Predictive factors for CME after DMEK require further study.

Topography-Guided Photorefractive Keratectomy for Postkeratoplasty Astigmatism: Long-Term Outcomes.

PURPOSE: To evaluate the long-term efficacy and safety of topography-guided photorefractive keratectomy (TG-PRK) for postkeratoplasty refractive error correction. METHODS: A retrospective interventional case series of 54 eyes of 50 patients who underwent previous corneal transplants. Unaided distance visual acuity (UDVA) and best corrected visual acuity (CDVA), manifest refraction, mean central keratometric value, mean keratometric astigmatism, and postoperative complications were reviewed. RESULTS: Final follow-up was at mean 31 (±17) months. Sixteen point seven percent of eyes underwent more than 1 surface ablation. Mean UDVA improved from 0.96 ± 0.06 logarithm of the minimum angle of resolution (LogMAR) preoperatively to 0.46 ± 0.05 LogMAR of resolution at the final follow-up (Bonferroni, P < 0.0001). Mean UDVA improved by 4.4 Snellen lines. Improvement in CDVA was not significant, although a significant improvement was noted when eyes with preoperative CDVA <20/40 were analyzed separately (t test, P = 0.005). Mean astigmatism improved from -4.4 ± 0.26 D preoperatively to -2.4 ± 0.26 D at the final follow-up (Bonferroni, P < 0.0001), whereas mean SEQ improved from -2.5 ± 0.39 D preoperatively to -1.1 ± 0.25 D (Bonferroni, P = 0.02). In total, 9% at the preoperative visit and 55% at the final visit had less than 2 D of astigmatism, respectively. Keratometric astigmatism decreased from 5.24 ± 0.36 D preoperatively to 2.98 ± 0.34 D at the final follow-up (t test, P < 0.0001). No eyes developed clinically significant haze, 14.8% developed regression, and 13% had a reduction of 2 or more CDVA lines. CONCLUSIONS: Postkeratoplasty topography-guided photorefractive keratectomy has good long-term efficacy and safety, resulting in significant UDVA, refractive, and keratometric improvement. Regression can occur after the first year of treatment, emphasizing the importance of long-term follow-up.

Diffuse lamellar keratitis associated with tabletop autoclave biofilms: case series and review.

PURPOSE: To report a diffuse lamellar keratitis (DLK) cluster attributed to autoclave reservoir biofilm and to review the risk and prevention of DLK and toxic anterior segment syndrome (TASS) caused by such biofilms. SETTING: Refractive Surgery Center, University of California, Berkeley. DESIGN: Observational case-control study and review of literature. METHODS: Eyes were evaluated for DLK following laser in situ keratomileusis (LASIK) over a 5-year period. Multiple changes in surgical and operating room protocols were prompted by a cluster of DLK cases. The autoclave reservoir chamber wall was cultured for microbial contamination. The MEDLINE database was used to identify relevant past publications. RESULTS: From January 7, 2010, to December 18, 2014, 1115 eyes received LASIK. Between September 2, 2010, and June 11, 2012, 147 eyes of 395 LASIK cases developed DLK (37.2%). Systematic modifications in surgical protocols were unsuccessful in ending the prolonged cluster of DLK cases until the STATIM 2000 autoclave was replaced with a new STATIM autoclave and a reservoir sterilization and surveillance protocol implemented. Over the subsequent 30 months, DLK incidence was reduced to 2.2% (14 DLK cases from 632 total LASIK cases, P < .0001). The retired autoclave reservoir chamber wall cultures grew Pseudomonas aeruginosa and the Burkholderia cepacia complex. CONCLUSIONS: Fluid reservoirs of tabletop steam autoclaves can readily develop polymicrobial biofilms harboring microbial pathogens, whose inert molecular byproducts can cause DLK and TASS when introduced to the eye by surgical instruments. Stringent reservoir cleaning and maintenance may significantly reduce this risk by preventing and removing these biofilms.

A Nonproprietary Movement Analysis System (MoJoXlab) Based on Wearable Inertial Measurement Units Applicable to Healthy Participants and Those With Anterior Cruciate Ligament Reconstruction Across a Range of Complex Tasks: Validation Study.

BACKGROUND: Movement analysis in a clinical setting is frequently restricted to observational methods to inform clinical decision making, which has limited accuracy. Fixed-site, optical, expensive movement analysis laboratories provide gold standard kinematic measurements; however, they are rarely accessed for routine clinical use. Wearable inertial measurement units (IMUs) have been demonstrated as comparable, inexpensive, and portable movement analysis toolkits. MoJoXlab has therefore been developed to work with generic wearable IMUs. However, before using MoJoXlab in clinical practice, there is a need to establish its validity in participants with and without knee conditions across a range of tasks with varying complexity. OBJECTIVE: This paper aimed to present the validation of MoJoXlab software for using generic wearable IMUs for calculating hip, knee, and ankle joint angle measurements in the sagittal, frontal, and transverse planes for walking, squatting, and jumping in healthy participants and those with anterior cruciate ligament (ACL) reconstruction. METHODS: Movement data were collected from 27 healthy participants and 20 participants with ACL reconstruction. In each case, the participants wore seven MTw2 IMUs (Xsens Technologies) to monitor their movement in walking, jumping, and squatting tasks. The hip, knee, and ankle joint angles were calculated in the sagittal, frontal, and transverse planes using two different software packages: Xsens' validated proprietary MVN Analyze and MoJoXlab. The results were validated by comparing the generated waveforms, cross-correlation (CC), and normalized root mean square error (NRMSE) values. RESULTS: Across all joints and activities, for data of both healthy and ACL reconstruction participants, the CC and NRMSE values for the sagittal plane are 0.99 (SD 0.01) and 0.042 (SD 0.025); 0.88 (SD 0.048) and 0.18 (SD 0.078) for the frontal plane; and 0.85 (SD 0.027) and 0.23 (SD 0.065) for the transverse plane (hip and knee joints only). On comparing the results from the two different software systems, the sagittal plane was very highly correlated, with frontal and transverse planes showing strong correlation. CONCLUSIONS: This study demonstrates that nonproprietary software such as MoJoXlab can accurately calculate joint angles for movement analysis applications comparable with proprietary software for walking, squatting, and jumping in healthy individuals and those following ACL reconstruction. MoJoXlab can be used with generic wearable IMUs that can provide clinicians accurate objective data when assessing patients' movement, even when changes are too small to be observed visually. The availability of easy-to-setup, nonproprietary software for calibration, data collection, and joint angle calculation has the potential to increase the adoption of wearable IMU sensors in clinical practice, as well as in free living conditions, and may provide wider access to accurate, objective assessment of patients' progress over time.

Ten-year safety follow-up and post-explant analysis of an anterior chamber phakic IOL.

PURPOSE: To assess endothelial cell loss (ECL) rate and collect safety data in patients with AcrySof L-series Cachet phakic intraocular lens (pIOL) up to 10 years post-implantation. SETTING: Clinical settings in the United States, European Union, and Canada. DESIGN: Nonrandomized, observational, open-label safety study. METHODS: Central and peripheral endothelial cell density was evaluated and compared with 6-month post-implantation baseline. Nonlinear analysis was performed to identify factors affecting post-explantation ECL. Additional evaluations included uncorrected visual acuity (UCVA), corrected distance visual acuity (CDVA), adverse device effects (ADEs), and serious adverse events (SAEs). RESULTS: The study included 1123 implanted eyes (mean age, 37.5 years). At 10 years, mean central and peripheral ECL was 16% (1.7% annualized). Explantations were performed in 10% of eyes (n = 136/1323). For eyes with pIOL explantation because of ECL (7%), annualized ECL rate post-explantation was numerically lower compared with the overall rate in eyes that underwent explantation for any reason (annualized rate, -1.65% vs -2.03%, respectively; n = 96) and compared with pre-explantation ECL. Mean ± SD CDVA and UCVA were -0.12 ± 0.11 and 0.03 ± 0.22 logarithm of the minimum angle of resolution, respectively. Common ocular ADEs included ECL (10%), pIOL extraction (9%), iris adhesion (7%), and pupillary deformity (2%). Common SAEs included pIOL extraction (11%), ECL (9%), and iris adhesions (8%). CONCLUSIONS: Cachet pIOLs were associated with long-term ECL in some cases. Overall, only 10% of all implanted eyes underwent explantation during 10-year follow-up. In patients requiring explantation because of ECL, the annualized ECL rates decreased post-explantation in some eyes. Continued monitoring of patients regardless of explantation is recommended.

Refractive Outcomes of Descemet Membrane Endothelial Keratoplasty Combined With Cataract Surgery in Fuchs Endothelial Dystrophy.

PURPOSE: To evaluate the refractive outcomes of Descemet membrane endothelial keratoplasty combined with cataract surgery (DMEK triple) in patients with Fuchs endothelial dystrophy. METHODS: A retrospective analysis of 68 eyes of 68 patients with Fuchs endothelial dystrophy who underwent DMEK triple between 2014 and 2018. RESULTS: The mean age of patients was 66.5 ± 8.6 years, and 65% (44 of 68) were female. Mean target refraction was -0.69 diopters (D) (interquartile range: -0.80 to -0.50 D). At 6 months, 47% (32 of 68) and 63% (43 of 68) of eyes were within ±0.50 and ±1.00 D of target refraction, respectively. Among eyes greater than 0.50 D from target, 78% (28 of 36) were hyperopic surprises. Mean spherical equivalent at 6 months was -0.14 ± 1.26 D, representing a mean hyperopic shift of 0.55 D from target. Preoperative pachymetry was higher in eyes with greater than 0.50 D of hyperopic surprise (648 ± 60 vs 613 ± 49 µm, P = .04). Refractive shift was greater in eyes with a preoperative central corneal thickness of 640 µm or greater versus eyes with a central corneal thickness of less than 640 µm (+1.20 ± 0.92 vs +0.40 ± 0.99 D, P = .02). None of the eyes with a preoperative central corneal thickness of 640 µm or greater shifted myopically compared to target (range: -0.09 to +2.89 D). CONCLUSIONS: A mean hyperopic shift of 0.55 D from target refraction occurred after DMEK triple, and 47% of eyes were within 0.50 D of target refraction at 6 months postoperatively. Thicker corneas preoperatively had greater hyperopic shift. A greater myopic target refraction may be warranted in eyes with a preoperative central corneal thickness of 640 µm or greater. [J Refract Surg. 2020;36(10):661-666.].

Rhythmic Haptic Cueing Using Wearable Devices as Physiotherapy for Huntington Disease: Case Study.

BACKGROUND: Huntington disease (HD) is an inherited genetic disorder that results in the death of brain cells. HD symptoms generally start with subtle changes in mood and mental abilities; they then degenerate progressively, ensuing a general lack of coordination and an unsteady gait, ultimately resulting in death. There is currently no cure for HD. Walking cued by an external, usually auditory, rhythm has been shown to steady gait and help with movement coordination in other neurological conditions. More recently, work with other neurological conditions has demonstrated that haptic (ie, tactile) rhythmic cues, as opposed to audio cues, offer similar improvements when walking. An added benefit is that less intrusive, more private cues are delivered by a wearable device that leaves the ears free for conversation, situation awareness, and safety. This paper presents a case study where rhythmic haptic cueing (RHC) was applied to one person with HD. The case study has two elements: the gait data we collected from our wearable devices and the comments we received from a group of highly trained expert physiotherapists and specialists in HD. OBJECTIVE: The objective of this case study was to investigate whether RHC can be applied to improve gait coordination and limb control in people living with HD. While not offering a cure, therapeutic outcomes may delay the onset or severity of symptoms, with the potential to improve and prolong quality of life. METHODS: The approach adopted for this study includes two elements, one quantitative and one qualitative. The first is a repeated-measures design with three conditions: before haptic rhythm (ie, baseline), with haptic rhythm, and after exposure to haptic rhythm. The second element is an in-depth interview with physiotherapists observing the session. RESULTS: In comparison to the baseline, the physiotherapists noted a number of improvements to the participant's kinematics during her walk with the haptic cues. These improvements continued in the after-cue condition, indicating some lasting effects. The quantitative data obtained support the physiotherapists' observations. CONCLUSIONS: The findings from this small case study, with a single participant, suggest that a haptic metronomic rhythm may have immediate, potentially therapeutic benefits for the walking kinematics of people living with HD and warrants further investigation.