Development of a Web-Based Algorithm for Understanding the Intraocular Lens-Based Surgery in Stable and Progressing Keratoconus for Non-Specialist Ophthalmologists.

PURPOSE: To propose an algorithm to facilitate lens-based surgery in keratoconus. METHODS: A literature review was performed to prepare a software algorithm based on cone location, stability, best spectacle-corrected distance visual acuity (BSCVA) level and whether there is a clear or cataractous lens. The software usability was assessed through a 10-question questionnaire and two hypothetical keratoconus case histories (moderately simple and moderately complex) given to 15 trainees. The usability questionnaires were graded on a Likert scale (1 = strongly disagree to 5 = strongly agree) and two case histories (1 = very difficult to 7 = very easy). RESULTS: The algorithm can be found at https://www.sussexeyelaserclinic.co.uk/keratoconus/. Thirteen trainees completed the questionnaire. 91.9% would frequently use it; for 100%, it was easy to use independently without technical support; for 63.7%, it was strongly integrated; for 100%, it was consistent; 100% thought that most people would learn to use it quickly, 91.9% found the system not cumbersome to use, felt very confident to use it and need not learn a lot to use it. The first case was found easy by 63.7% and the second by 45%. CONCLUSION: We present an algorithm as a guide for lens-based surgery in stable and progressing keratoconus, which is classified based on cone location. This algorithm will help trainee and "non-specialist" ophthalmic surgeons understand the pre-operative planning for the surgery and referral to the "specialist" corneal surgeon, considering factors such as progression, BSCVA, keratometry, topography and apex location of the cone in keratoconus patients.

Amantadine-induced corneal edema: A case and literature review.

Purpose: To present a case of irreversible corneal edema after 10 years of amantadine use. A literature review was carried out to describe the clinical characteristics and outcomes of amantadine-induced corneal edema. Observations: A 36-year-old woman presented with a 6-week history of gradually progressive bilateral painless visual loss with visual acuity (VA) of 20/350 and 20/300 in the right and left eye, respectively. Examination showed bilateral diffuse central corneal edema with multiple Descemet membrane folds without endothelial guttata, keratic precipitates or intraocular inflammation. This did not respond to hypertonic saline drops and empirical treatment for presumed herpetic endotheliitis with oral acyclovir. Medication review revealed the use of amantadine 100mg daily for the past 10 years, prescribed by her neurologist for fatigue. Despite discontinuing amantadine, corneal edema was irreversible due to a markedly reduced endothelial cell count of 625 (right) and 680 cells/mm2 (left). Conclusions and Importance: This case highlights the need to consider amantadine as a cause of unexplained bilateral non-guttae corneal edema. A literature review of 33 case reports revealed broadly similar features of amantadine-induced corneal edema; whilst most cases had favorable outcomes with median VA 20/25 (interquartile range IQR 20/20-20/30) and complete resolution of corneal edema within 30 days (IQR 14-35) of amantadine discontinuation, most experienced low endothelial cell density 759 cells/mm2 (IQR 621-1078). Taken together, screening specular microscopy ought to be considered for those in whom amantadine is likely required long-term.

Incidence and factors for pseudoaccommodation after monofocal lens implantation: the Monofocal Extended Range of Vision study.

PURPOSE: To screen patients with a monofocal intraocular lens (IOL) for incidence of unaided 20/40 and 0.3 LogMAR for distance and near (pseudoaccommodation) and to find factors for pseudoaccommodation. SETTINGS: University Hospitals Sussex NHS Foundation Trust, Brighton, United Kingdom. DESIGN: Prospective study. METHODS: This was a single-eye study ( ClinicalTrials.gov : NCT04011696). At 3 to 9 months, refraction, uncorrected and corrected distance and uncorrected near visual acuity (logMAR), spherical equivalent (SEQ), mesopic pupil size (PS), total eye spherical (Z 40 ), vertical coma (Z 3-1 ) aberrations, reading speed and smallest print size were assessed. Refractive astigmatism (RA) was classified as against-the-rule, with-the-rule, oblique and no astigmatism. Data on preoperative axial length (AL) and anterior chamber depth (ACD) were collected. RESULTS: 29 patients (9.6%, 95% CI, 6.5-13.5) had pseudoaccommodation. In cases vs controls, median SEQ, PS, total Z 40 , Z 3-1 , reading speed, smallest print size, preoperative ACD, preoperative AL were: -0.39 vs 0.0 diopters; 3.62 vs 4.10 mm; 0.01 vs 0.02 µm; 0.018 vs 0.022 µm; 106 vs 133 words per minute; 0.30 vs 0.50 logMAR; 2.94 vs 3.13 mm, 23.4 vs 23.7 mm, respectively. RA was not different between the groups. Univariate analysis revealed preoperative ACD (odds ratio [OR], 0.38, 95% CI, 0.16-0.94, P = .04), SEQ (OR, 0.61, 95% CI, 0.42-0.88, P = .01), total Z 40 (OR, 0.0003, 95% CI, 0.00-0.39, P = .03) and PS (OR, 0.39, 95% CI, 0.22-0.69, P < .041) to be significant. Whereas multivariable logistic regression identified: preoperative AL (OR, 0.62, 95% CI, 0.42-0.91, P = .02), SEQ (OR, 0.49, 95% CI, 0.31-0.78, P = .01), Z 40 (OR, 0.00, 95% CI, 0.0-0.01, P = .01) and PS (OR, 0.41, 95% CI, 0.23-0.75, P = .01) to be significant. CONCLUSIONS: A combination of low myopic SEQ, lower Z 40 , shorter preoperative AL, and smaller PS increases the chances of pseudoaccommodation.

Management of Stromal Corneal Dystrophies; Review of the Literature with a Focus on Phototherapeutic Keratectomy and Keratoplasty.

Corneal dystrophies are a group of non-inflammatory inherited disorders of the cornea. This review considers treatment options for epithelial-stromal and stromal corneal dystrophies: namely Reis-Bücklers, Thiel-Behnke, lattice, Avellino, granular, macular and Schnyder corneal dystrophies. Where there is visual reduction, treatment options may include either phototherapeutic keratectomy (PTK) or corneal transplantation. Due to the anterior location of the deposits in Reis-Bücklers and Thiel-Behnke dystrophies, PTK is considered the treatment of choice. For lattice, Avellino, granular and macular corneal dystrophies, PTK provides temporary visual improvement; however, with recurrences, repeat PTK or a corneal transplant would be needed. For Schnyder dystrophy, should treatment be required, PTK may be the preferred option due to the potential for recurrence of the disease in corneal transplantation. This review discusses the literature and evidence base for the treatment of corneal dystrophies in terms of visual outcomes and recurrence rate.

Full-Thickness Compressive Corneal Sutures with Removal of Anterior Chamber Air Bubble in the Management of Acute Corneal Hydrops.

Acute hydrops is a rare complication of corneal ectatic disease, which occurs secondary to Descemet membrane break. Spontaneous resolution of this condition is associated with longstanding ocular discomfort and corneal scar. Intracameral gas/air injection with or without corneal suturing, anterior segment ocular coherence tomography (ASOCT)-guided drainage of intrastromal fluid, and penetrating keratoplasty are some of the described surgical interventions to manage this condition. The purpose of our study was to assess the effect of full-thickness corneal suturing as a solo treatment in the management of acute hydrops. A total of five patients with acute hydrops received full-thickness corneal sutures perpendicular to their Descemet break. A complete resolution of symptoms and corneal oedema was observed between 8 to 14 days post-operation with no complications. This technique is simple, safe, and effective in the management of acute hydrops and saves patients from a corneal transplant in an inflamed eye.

Preoperative fundoscopy versus optical coherence tomography to detect occult maculopathy during cataract surgery preassessment.

PURPOSE: To assess the proportion of maculopathy detectable only on optical coherence tomography (OCT) versus slit lamp indirect ophthalmoscopy (SLIO) during cataract assessment. METHODS: Population: Consecutive patients attending cataract assessments. DATA COLLECTION: All patients underwent OCT and SLIO. SLIO findings were recorded before reviewing OCT. Scans were examined to compare with recorded SLIO findings. PRIMARY OUTCOME: analyse the proportion of eyes with maculopathy missed by SLIO. SECONDARY OUTCOME: to assess the proportion of patients with maculopathy on OCT, the incidence of maculopathy in the fellow eye on OCT and proportion with cataracts too dense to allow SLIO or OCT. RESULTS: Six hundred twenty-six patients were enroled. Eighty (12.8%) had maculopathy detectable only on OCT which included: 26 (4.2%) epiretinal membrane (ERM), 25 (4%) dry age-related macular degeneration (AMD), 19 (3%) vitreomacular traction (VMT), 5 (0.8%) lamellar macular hole (LMH), 2 (0.3%) cystoid macular oedema (CMO) and 1 (0.2%) wet AMD. 166 (26.5%) had maculopathy on OCT, of which only 48 (7.7%) had known history of maculopathy. In fellow eyes, 29 (4.6%) had significant findings and 29 (4.6%) were unable to have SLIO or OCT due to dense cataract. CONCLUSIONS: A quarter of the patients had occult maculopathy. One-tenth of the occult maculopathy were missed without OCT, with ERM, dry AMD, VMT, LMH, CMO and wet AMD being the primary missed diagnosis. Less than 5% had occult maculopathy in fellow eye, and <5% had dense cataracts where neither SLIO nor OCT was not possible.

Ex-vivo study on the surface quality of corneal lenticule and stroma after low energy femtosecond laser lenticule extraction.

This study aimed to assess the surface quality of cap, stroma and lenticular surfaces created using low-energy femtosecond laser lenticule extraction (Ziemer FEMTO LDV Z8). Twenty-four porcine eyes were divided into four groups (n = 6 each): two with optimal laser power (32%) with posterior curvature equivalent to a spherical correction of -2D and -5D, respectively and the other two with high power (64%) with spherical correction of -2D and -5D respectively. Samples were analysed using scanning electron microscopy (SEM). Surface morphology was evaluated using a standard scoring system; surface relief, surface regularity, extent and position of irregularities were graded by four independent clinicians. Eyes with 32% power and -2D correction had significantly less size of the irregular area than those with -5D; however, no significant difference was found between the two groups with 64% power. When comparing eyes with -2D correction, the size of the irregular area was lesser with 32% power. Surface relief was lesser with -5D correction with 32% power than 64% power. Low-energy femtosecond laser lenticule extraction (Ziemer FEMTO LDV Z8) produces good surface quality results. There is a tendency for smoother surface stromal quality with lower power settings than a higher power.

Flattening of Central, Paracentral, and Peripheral Cones After Non-accelerated and Accelerated Epithelium-off CXL in Keratoconus: A Multicenter Study.

PURPOSE: To assess the flattening of central, paracentral, and peripheral cones following non-accelerated (non-A-CXL) and accelerated (A-CXL) epithelium-off corneal cross-linking with 10 times higher intensity. METHODS: In this multicenter study of 200 eyes (100 in each group), following 10 minutes of soak time with riboflavin 0.1%, continuous CXL was performed for 30 minutes (intensity: 3 mW/cm2, fluence: 5.4 J/cm2) in the non-A-CXL group and 3 minutes (intensity: 30 mW/cm2, fluence: 5.4 J/cm2) in the A-CXL group. Anterior and posterior cone flattening were compared at 12 months. Multiple regression analysis was performed to establish correlation of age, sex, cone location, and preoperative maximum keratometry (Kmax) values with postoperative flattening at 12 months. RESULTS: In the non-A-CXL and A-CXL groups, central cones were the steepest, followed by paracentral and peripheral cones. Both groups showed significant flattening in central (1.54 ± 1.94 and 1.09 ± 1.79 diopters [D]) and paracentral (0.62 ± 1.59 and 0.55 ± 0.98 D) cones only. In the non-A-CXL group, there was a positive correlation between postoperative flattening and preoperative Kmax values, whereas paracentral and peripheral cone locations were negatively related. In the A-CXL group, only paracentral location was negatively correlated to postoperative flattening and showed posterior cone steepening at 12 months. CONCLUSIONS: Although central cones were the steepest in both groups, there was no difference in postoperative flattening between the groups for all cone locations. In the non-A-CXL group, postoperative flattening was proportional to preoperative Kmax values in central cones and was less with paracentral and peripheral locations. With A-CXL, postoperative flattening was less only with paracentral location. In the A-CXL group, significant posterior cone steepening was noticed only in paracentral cones. [J Refract Surg. 2022;38(5):310-316.].

Comparison of Anterior Corneal Aberrometry, Keratometry and Pupil Size with Scheimpflug Tomography and Ray Tracing Aberrometer.

This study aimed to assess the anterior corneal wavefront aberrations, keratometry, astigmatism vectors and pupil size between Pentacam HR® (Oculus Optikgeraete GmbH, Wetzlar, Germany) and iTrace® (Tracey Technologies Corp., Houston, TX, USA). In this observational study, 100 eyes (50 healthy volunteers) were scanned in mesopic light condition with a Pentacam HR® and iTrace®. Anterior corneal aberrations (spherical aberration (Z40), vertical coma (Z3 − 1), horizontal coma (Z3 + 1)), keratometry in the flattest (K1) and steepest meridian (K2), mean astigmatism, astigmatic vectors (J0 and J45), and pupil size were measured. We found a significant difference in Z40 (Pentacam®: +0.30 ± 0.11 µm and iTrace®: −0.03 µm ± 0.05 µm; p < 0.01) with no correlation between the devices (r = −0.12, p = 0.22). The devices were in complete agreement for Z3 − 1 (p = 0.78) and Z3 + 1 (p = 0.39), with significant correlation between the machines (r = −0.38, p < 0.01 and r = −0.6, p < 0.01). There was no difference in K1, K2 and mean astigmatism. J0 was negative with both devices (against-the-rule astigmatism), but there was no correlation. J45 was negative with the Pentacam HR® (more myopic oblique astigmatism) but significantly correlated between the devices. Pupil size was smaller with Pentacam HR® (p < 0.01). In summary, these devices cannot be used interchangeably. Corneal Z40 was significantly different with more negative Z40 with iTrace® compared to Pentacam HR®. iTrace® operates with lower illumination, giving larger pupil size than Pentacam HR®, which uses intense blue light during measurement. No correlation was found for J0. Pentacam HR® had a trend to record more negative J45 (myopic oblique astigmatism).

Visual Acuity, Wavefront Aberrations, and Defocus Curves With an Enhanced Monofocal and a Monofocal Intraocular Lens: A Prospective, Randomized Study.

PURPOSE: To compare uniocular and binocular visual acuity, wavefront aberrations, and defocus curves using the TECNIS Eyhance (Johnson & Johnson) and RayOne (Rayner) intraocular lenses (IOLs). METHODS: In this prospective, randomized, comparative study, 50 patients (100 eyes) were randomized to receive the same IOL bilaterally (ClinicalTrials.gov Identifier: NCT04175951). Follow-up visits were at 1 and 3 to 9 months postoperatively. Primary outcome measures were uncorrected distance (UDVA) and uncorrected intermediate (UIVA) visual acuity (logMAR) at 66 cm. Secondary outcome measures were corrected distance (CDVA) and distance-corrected intermediate (DCIVA) visual acuity at 66 cm, manifest refraction, spherical (Z40) and vertical coma (Z3-1) aberrations (total, internal eye, and corneal) at normal pupil size, defocus curves, and Catquest 9SF and Glare and Halos questionnaire on Likert scale (1 = no glare and halos and 4 = continuous). RESULTS: Uniocular UDVA (P = .02), UIVA (P = .02), and binocular UIVA (P < .01) and uniocular (P = .01) and binocular (P < .01) DCIVA were better with the TECNIS Eyhance IOL at 3 to 9 months. At 3 to 9 months, both uniocular and binocular defocus curves were significantly broader with the TECNIS Eyhance IOL between -0.50 and -3.00 diopters (D). For total and internal eye, there was a statistically but clinically insignificant difference in Z40 with the TECNIS Eyhance IOL. Rasch scores improved (TECNIS Eyhance: 2.04 ± 1.34 to 2.91 ± 0.81 and RayOne:1.61 ± 1.35 to 2.97 ± 0.16) at 3 to 9 months. Refraction, Z3-1, glare, and halos were not different. CONCLUSIONS: The TECNIS Eyhance IOL provided better DCIVA and broader defocus curves than the RayOne IOL. There was no difference in CDVA or patient-reported outcomes. Although there were some differences in aberrations when measured with normal pupil size, they were not clinically significant. [J Refract Surg. 2022;38(1):10-20.].

Comparison of intraocular lens calculation methods after myopic laser-assisted in situ keratomileusis and radial keratotomy without prior refractive data.

AIM: To compare intraocular lens (IOL) calculation methods not requiring refraction data prior to myopic laser-assisted in situ keratomileusis (LASIK) and radial keratotomy (RK). METHODS: In post-LASIK eyes, the methods not requiring prior refraction data were Hagis-L; Shammas; Barrett True-K no-history; Wang-Koch-Maloney; 'average', 'minimum' and 'maximum' IOL power on the American Society of Cataract and Refractive Surgeons (ASCRS) IOL calculator. Double-K method and Barrett True-K no-history, 'average', 'minimum' and 'maximum' IOL power on ASCRS IOL calculator were evaluated in post-RK eyes. The predicted IOL power was calculated with each method using the manifest postoperative refraction. Arithmetic and absolute IOL prediction errors (PE) (implanted-predicted IOL powers), variances in arithmetic IOL PE and percentage of eyes within ±0.50 and ±1.00 D of refractive PE were calculated. RESULTS: Arithmetic or absolute IOL PE were not significantly different between the methods in post-LASIK and post-RK eyes. In post-LASIK eyes, 'average' showed the highest and 'minimum' showed the least variance, whereas 'average' and 'minimum' had highest percentage of eyes within ±0.5 D and 'minimum' had the highest percentage of eyes within ±1.0 D. In the post-RK eyes, 'minimum' had highest variance, and 'average' had the least variance and highest percentage of eyes within ±0.5 D and ±1.0 D. CONCLUSION: In post-LASIK and post-RK eyes, there are no significant differences in IOL PE between the methods not requiring prior refraction data. 'Minimum' showed least variance in PEs and more chances of eyes to be within ±1.0 D postoperatively in post-LASIK eyes. 'Average' had least variance and more chance of eyes within ±1.0 D in post-RK eyes.

Pericardium Patch Graft for Severe Corneal Wound Burn.

PURPOSE: To report a novel management technique using pericardial patch graft for severe corneal wound burn following phacoemulsification of dense cataract with shallow anterior chamber (AC) and overfilled AC with viscoelastic. METHODS: Case report. RESULTS: A 46-year-old patient with a shallow AC and dense cataract, who underwent phacoemulsification using "soft shell" technique had severe wound burn which was refractory to conventional management with corneal suturing and placing bandage contact lens. He underwent Tutoplast® (Innovative Ophthalmic Products, Inc., Costa Mesa, CA, USA) pericardium patch graft, which fully resorbed and resolved the wound leak over 6 weeks, leaving a well-healed corneal wound. CONCLUSION: Pericardium patch graft is a safe and effective technique to manage extensive phaco wound burn which is refractory to conventional management options.

Descemet membrane suturing to manage recurrent graft detachment in a patient with Descemet membrane endothelial keratoplasty on failed penetrating keratoplasty.

A 65-year-old patient with history of keratoconus, mild cataract and penetrating keratoplasty over 30 years ago developed corneal oedema subsequent of graft failure with best corrected visual acuity (BCVA) of counting fingers. He underwent a successful cataract surgery combined with a 7.25 mm Descemet's Membrane Endothelial Keratoplasty (DMEK) with Sodium Hexafluoride (SF6) gas. His cornea remained oedematous inferiorly at 4 weeks, despite two subsequent re-bubbling due to persistent DMEK detachment inferiorly. This was managed by three radial full thickness 10-0 nylon sutures placed in the inferior cornea along with intracameral injection of air. Following this, his anterior segment ocular coherence tomography (OCT) confirmed complete attachment of the graft, and the sutures were removed 4 weeks later. Unaided visual acuity was 20/63 and BCVA was 20/32 after 8 months. DMEK suturing can be helpful in persistent DMEK detachments, which is refractory to repeated re-bubbling due to uneven posterior surface of previous PK.

Prophylactic Use of Nonsteroidal Anti-Inflammatory Drugs after Cataract Surgery and Corneal Melt.

PURPOSE: To describe a case where prophylactic use of nonsteroidal anti-inflammatory drugs (NSAID) eye drops lead to recurrent corneal melt with loss of vision and a brief literature review. METHODS: This is a case report of an 84-year-old diabetic female with chronic dry eye, operated by two different surgeons on each eye at different time intervals. She received topical NSAID prophylaxis after the second surgery only, which led to blindness due to recurrent corneal melt and chronic choroidal effusions. We also present a brief literature review. RESULTS: This lady presented with corneal melt and perforation 5 days following the use of topical NSAIDs prophylaxis after a routine cataract surgery in the second eye. Unfortunately, all efforts to save her vision and eye were unsuccessful as she developed repeated complications in spite of corneal gluing, amniotic membrane, penetrating keratoplasty, and tarsorrhaphy. She also had chronic choroidal effusions. She ended up with an opaque cornea and a subtotal tarsorrhaphy, with no other option to improve her vision as she did not qualify for sedation or general anesthesia due to her poor systemic health. CONCLUSION: Although it is a common practice for diabetic patients to have topical NSAIDs prophylaxis in combination with steroid eye drops to reduce the risk of cystoid macular edema after cataract surgery, the elderly diabetic patients with concomitant dry eyes should be considered high risk for corneal melt and should be closely monitored. This case highlights the rare but serious complication of topical NSAIDs prophylaxis in the vulnerable cornea, which warrants careful consideration.

Autoimmune Dry Eye without Significant Ocular Surface Co-Morbidities and Mental Health.

Dry eye symptoms can negatively affect the psychological, physical, and social functioning, which can potentially impair the health-related quality of life. This review evaluated the association between autoimmune related dry eye in the absence of significant ocular surface co-morbidities and mental health. This review found a significantly higher prevalence of mental health disorders (such as depression and anxiety) in systemic lupus erythematous, rheumatoid arthritis, systemic sclerosis, Behcet's disease, and primary Sjogren's syndrome patients when compared to the general population. Moreover, patients with depression and anxiety interpret ocular sensations differently than healthy controls and the perception of dry eye symptoms can be influenced by their mood. Somatization is common in depression, and this could influence the perception of ocular discomfort. Anti-depressants and anxiolytics with their potential side effects on the tear film status may also contribute or aggravate the dry eye symptoms in these patients. Although ophthalmologists manage the dry eye disease, as per standardized algorithms, they should be mindful of different ocular sensation interpretation and coexistent mental health issues in a large number of this patient group and initiate a multidisciplinary management plan in certain cases. While rheumatologists look after their autoimmune condition, it may be worth liaising with GP and/or psychiatrist colleagues in order to address their neuropathic type pain and mental health co-morbidities.