Management of low astigmatism in implantable collamer lens surgery: opposite clear corneal incisions vs toric implantable collamer lens.

PURPOSE: To compare 2 techniques to correct low astigmatism during implantable collamer lens (ICL) surgery: astigmatic opposite clear corneal incisions (OCCIs) and toric ICL (T-ICL). SETTING: Arruzafa Ophthalmological Hospital, Cordoba, Spain. DESIGN: Randomized prospective comparative study. METHODS: The study comprised 152 myopic eyes undergoing ICL surgery. Patients were separated into 2 groups: Group 1 (57 patients; 76 eyes) received a spherical ICL with OCCIs and Group 2 (53 patients; 76 eyes) received a T-ICL. The inclusion criteria were refractive astigmatism up to 1.50 diopters (D), regular corneal astigmatism up to 2.00 D (Sim K, Pentacam), and agreement between the refractive and topographic corneal cylinders (discrepancies less than 30 degrees axis or 0.50 D). The outcomes were evaluated after a 1-month follow-up. RESULTS: The T-ICL group achieved a mean postoperative spherical equivalent refraction and refractive astigmatism of -0.04 ± 0.17 D and -0.03 ± 0.12 D, respectively, vs -0.14 ± 0.33 D and -0.20 ± 0.36 D, in the OCCI group ( P < .001). Postoperative refractive astigmatism of less than 0.25 D was achieved in 94.74% of cases in the T-ICL group vs 73.68% in the OCCI group. Undercorrection of corneal astigmatism occurred in the OCCI group with a surgically induced astigmatism of 0.48 ± 0.24 D and correction index = 0.46. CONCLUSIONS: Both the T-ICL and OCCI techniques provided excellent results in terms of safety and efficacy. T-ICL surgery was shown to be more predictable and accurate for correcting low astigmatism with a lower postoperative spherical equivalent and less residual astigmatism compared to incisional management.

Surgical correction of corneal opacity and aniridia with penetrating keratoplasty and a new iris prosthesis implant.

PURPOSE: This study is to describe the clinical outcome of penetrating keratoplasty combined with implantation of a novel intraocular lens with an artificial iris, aided by continuous vitreous chamber infusion, in patients with severe aniridia and corneal alterations. METHODS: This was a prospective single-center case series study involving five patients with corneal alterations and aniridia. All subjects underwent simultaneous penetrating keratoplasty and implantation of a new intraocular lens with an artificial iris with the assistance of infusion into the vitreous chamber to regulate intraocular pressure during the surgical procedure. Visual acuity, corneal endothelial cell density, and intraocular pressure assessments were performed in the postoperative period. The final cosmetic outcome of the iris prosthesis placement was also evaluated. RESULTS: In all cases, increased visual acuity and a good aesthetic result were observed in all affected eyes except one in which, despite the excellent aesthetic outcome, the eye was very hypotonic as it had high myopia and had undergone several previous surgeries. CONCLUSION: The single surgical procedure combining implantation of an intraocular lens-iris prosthesis with penetrating keratoplasty is an effective technique for the simultaneous treatment of aphakia and aniridia. However, larger series with longer-term follow-up are needed to definitively establish the benefits of this technique.

Comparison Between the Wavefront-Optimized and Custom-Q Aspheric Ablation Profiles in Myopic Eyes With Two Different Q-targets: A Contralateral Eye Study.

PURPOSE: To compare two aspheric ablation profiles in myopic refractive surgery using different asphericity targets. METHODS: Patients underwent laser in situ keratomileusis (LASIK) with the WaveLight EX500 laser platform (Alcon, WaveLight Laser Technologie). Asymmetric surgery was performed, programming the wavefront-optimized (WFO) ablation profile in one eye and the custom-Q (CQ) profile in the contralateral eye. The patients were divided into two groups following a systematic randomization method. The Q-target programmed for the preoperative Q group was equal to the preoperative asphericity of the CQ profile, and for the -0.6 Q-target group, the Q-target was set to -0.6. RESULTS: The study included 100 patients (200 eyes). Both groups had comparable safety and efficacy indexes greater than 1. A similar oblate shift in postoperative asphericity was seen in both groups regardless of the ablation profile and programmed Q-target. Asphericity was 0.33 ± 0.34 and 0.35 ± 0.29 (P = .18) in the preoperative Q group and 0.26 ± 0.28 and 0.26 ± 0.27 (P = .89) in the -0.6 Q-target group for WFO and CQ, respectively. A lower spherical aberration was found with CQ compared to WFO when the Q-target was set to -0.6: 0.211 ± 0.121 versus 0.144 ± 0.114 (P < .01). However, no statistically significant differences were found when the preoperative Q-target was used. CONCLUSIONS: WFO and CQ treatments are similar in terms of refractive and visual outcomes. CQ offers greater control over the increase in positive spherical aberration after myopic refractive surgery, but it does not represent an advantage over WFO in the oblate shift in postoperative asphericity regardless of the Q-target programmed. [J Refract Surg. 2022;38(11):698-707.].

Comparison of wound architecture in implantable collamer lens surgery: Self-sealing single-plane opposite clear corneal incision versus main surgical incision.

PURPOSE: Incision architecture can play an important role in corneal astigmatism management through peripheral corneal relaxing incisions. The aim of this study was to compare the incision architecture of single-plane opposite clear corneal incisions (OCCIs) and main surgical incisions (MSIs) in patients undergoing implantable collamer lens (ICL) surgery. METHODS: A retrospective cross-sectional tomographic analysis of MSI and OCCI architectures was performed 6 months after ICL surgery. Image acquisition was performed using spectral-domain anterior segment optical coherence tomography. RESULTS: A total of 31 OCCIs and 24 MSIs were evaluated. The mean incision angle was 42.83 ± 5.69 degrees for MSIs and 48.26 ± 6.07 degrees for OCCIs (p < 0.01), and the mean MSI and OCCI length was 1146.70 ± 150.48 µm and 976.68 ± 140.19 µm, respectively (p < 0.01). The mean increase in epithelium depth in the wound was 37.63 ± 11.91 µm in the MSI group and 47.64 ± 15.45 µm in the OCCI group (p = 0.02). Endothelial misalignment was observed in both types of incisions. However, the misalignment with MSI was greater than with OCCI, 106.67 ± 31.84 µm versus 83.75 ± 23.39 µm (p = 0.01), respectively. CONCLUSION: Both types of incisions, OCCI and MSI, were shown to be safe with complete wound sealing and healing 6 months postoperatively. The MSIs performed in the temporal position were more angled and longer, with greater endothelial retraction and minor epithelial thickening in the wound area compared with astigmatic incisions without manipulation.

Comparison of 3-month visual outcomes of a new multifocal intraocular lens vs a trifocal intraocular lens.

PURPOSE: To compare the clinical performance of the TECNIS Synergy multifocal (model ZFR00V) intraocular lens (IOL) with that of the AcrySof PanOptix Trifocal (model TFNT00) IOL in patients undergoing bilateral cataract surgery. SETTING: Multicenter clinical setting. DESIGN: Prospective randomized comparative study. METHODS: Patients aged 22 years or older were randomly assigned (2:1) to bilateral implantation with ZFR00V or TFNT00 IOLs. End points included the mean binocular distance-corrected near visual acuity (DCNVA) at 40 cm, photopic and mesopic DCNVAs at 33 cm, photopic low-contrast corrected distance visual acuity (CDVA) and mesopic CDVA, nondirected patient responses to an ocular/visual symptoms questionnaire, and safety. RESULTS: Of the 150 patients implanted with IOLs, 95 of the 97 patients with ZFR00V IOLs and 52 of the 53 patients with TFNT00 IOLs completed the 3-month follow-up. Most patients in the ZFR00V and TFNT00 groups achieved 20/25 or better binocular CDVA (100% vs 96.2%) and DCNVA measured at 40 cm (88.4% vs 75.0%) and 33 cm (78.9% vs 51.9%). The mean between-group difference in binocular DCNVA at 40 cm favored ZFR00V IOLs (0.5 lines Snellen; 95% CI, 0.012 to 0.089; P ≤ .05). Similarly, the mean binocular photopic and mesopic DCNVAs at 33 cm (0.8 lines Snellen each; both P ≤ .05 vs TFNT00) and photopic high-contrast and low-contrast CDVA (0.5 lines Snellen each; both P ≤ .05 vs TFNT00) favored ZFR00V IOLs. Patient-reported ocular/visual symptoms and safety were generally similar between the 2 IOLs. CONCLUSIONS: The ZFR00V IOL showed an extensive range of vision, particularly through near distances, and better mesopic performance than the TFNT00 IOL in patients undergoing cataract surgery.

Astigmatism correction with toric implantable collamer lens in low and high astigmatism groups.

PURPOSE: To analyze the target induced astigmatism (TIA), surgically induced astigmatism (SIA), difference vector (DV), and correction index (CI) in the correction of astigmatism with phakic lenses, and its influence on visual acuity, and to analyze the safety and efficacy indexes of the correction of high and low power astigmatism with toric phakic lenses. DESIGN: Retrospective comparative study. METHODS: The medical records of patients that were operated on at the research center during the period were analyzed. Results were divided into Low Astigmatism Group - LAG (33 eyes) and High Astigmatism Group - HAG (93 eyes) according to the implanted toric ICL lens power. Preoperative refraction and resultant postoperative refraction were analyzed by vector analysis. Visual acuity pre and postop, with and without optical correction, were compared. RESULTS: A total of 126 eyes were studied. The average preop refraction was -5.02 D sphere with -2.61 D cylinder. The average ICL lens power implanted was -8.31 D sphere +2.77 D cylinder. Refractive remaining was -0.01 ± 0.11 D sphere -0.15 ± 0.28 D cylinder. The arithmetic average angle of error in the astigmatism correction was 1.08°. The resultant cylinder was -0.03 ± 0.12 D and -0.19 ± 0.30 D in the low and high astigmatism groups, respectively, with a mean UDVA -0.01 ± 0.10 and 0.01 ± 0.16 and CDVA -0.03 ± 0.08 and -0.01 ± 0.17 for each group. The safety and efficacy indexes for the low astigmatism group were 1.09 ± 0.16 and 1.05 ± 0.17, respectively, with 1.11 ± 0.17 and 1.06 ± 0.16 for the high astigmatism group. CONCLUSIONS: The correction of astigmatism by the implantation of toric phakic lenses of the posterior chamber is safe and effective, independently of the amount of cylinder corrected.

Nomogram for single-pass automated microkeratome graft preparation for ultrathin Descemet stripping automated endothelial keratoplasty.

PURPOSE: To create a nomogram including the translational speed of the microkeratome blade, microkeratome head size and precut tissue thickness to predict the postcut thickness for Descemet stripping automated endothelial keratoplasty to obtain the thinnest possible graft. METHODS: This prospective study incorporated 48 grafts for DSAEK from March 2017 to June 2020. Corneal tissue for DSAEK was prepared by 3 experienced physicians using the Moria Evolution 3E (Moria Inc, Antony, France) microkeratome with 400, 450 and 500 µm head sizes. Precut central corneal thickness was measured with a DGH 550 handheld pachymeter (Pachette 2), taking an average of 3 readings. The microkeratome head was selected according to precut tissue thickness. The selected microkeratome head size was 150 µm less than the donor cornea thickness. Two translational speeds were used for the microkeratome cuts. One month after surgery, the central lenticular thickness was measured with a Visante® Optical Coherence Tomography caliper (Carl Zeiss Meditec Inc, Germany). A descriptive analysis was performed. RESULTS: Forty-eight donor grafts were prepared. Mean graft thickness was 97.58 ± 29.84 µm (range 39-176 µm). Of the 48 samples, central graft thickness was < 120 µm (81.3%) in 39, < 100 µm (58.3%) in 28 and < 80 µm (37.5%) in 18 at 1-month follow-up. There were no statically significant differences between translational speeds. CONCLUSIONS: A nomogram with an automated microkeratome to obtain thin grafts for DSAEK provided good graft thickness results without donor waste.

Aberrometric, Keratometric, and Visual Outcomes After Trans-Epithelial Topography-Guided Phototherapeutic Keratectomy for the Treatment of Irregular Corneas.

PURPOSE: To assess the safety, aberrometric and keratometric changes, and stability of trans-epithelial topography-guided phototherapeutic keratectomy (TE-TG-PTK) with mitomycin C (MMC) using the ALLEGRO Topolyzer platform for the treatment of irregular astigmatism. METHODS: This is a retrospective case series including 57 eyes that underwent TE-TG-PTK + MMC using the ALLEGRO Topolyzer platform for the treatment of irregular astigmatism. CDVA, manifest refraction (MR), keratometry readings, and aberrometry readings were analyzed at 1, 3, 6, and 12 months. RESULTS: Causes of corneal irregularity included non-infectious leucoma (n=23), infectious leucoma (n=7), adenoviral keratitis (n=20), corneal haze (n=2), post-penetrant keratoplasty (PKP) (n=1), and others (n=4). Overall, 76% of the eyes (n=40) gained lines of vision; patients gained 1, and 2 or more lines of vision in 76%, and 38% of cases, respectively. Only 1 patient (2%) lost 5 lines of vision. Mean preoperative CDVA (LogMAR) was 0.37 ±0.31 and improved to 0.14 ±0.18 (p<0.001) at final follow-up (12 months). CDVA remained unchanged in 10 eyes (21%). No significant changes were observed in mean keratometry (Kmean) and keratometric astigmatism readings. Regarding aberrometry, only changes in coma proved to be significant 6 months after surgery (P<0.01). No intraoperative/postoperative complications were reported. CONCLUSION: At final follow-up, significant improvements were observed in CDVA and coma. TE-TG-PTK + MMC proved to be an effective and safe procedure for the treatment of corneal irregular astigmatism due to several causes.

Scanning Electron Microscope Analysis of Stromal Surface Regularity in DSAEK Using Manual or Automated Microkeratomes or DMEK.

PURPOSE: To analyze differences in the stromal bed according to the method used to obtain the disc for endothelial transplant with 1) an automated microkeratome for Descemet stripping automated endothelial keratoplasty (DSAEK), 2) homogeneous dissection of Descemet membrane (Descemet membrane endothelial keratoplasty [DMEK]), or 3) a manual microkeratome used for DSAEK. METHODS: We analyzed the stromal bed of 25 consecutive corneas used for endothelial transplantation, divided into 3 groups: 1) 11 samples cut with an automated microkeratome, 2) 5 samples used for DMEK, 3) 9 samples cut with a manual microkeratome. A scanning electron microscope was used to obtain an image of the center of the stromal bed. The irregularity index of the surface complementary to the stromal surface of the disc obtained for grafting was calculated with the Canny algorithm (0: completely smooth; 1: completely irregular). RESULTS: At all thresholds studied (20, 30, 50, and 70), the mean irregularity index for group C (35.2, 24.4, 13.7, and 8.8, respectively) was higher than that of group A (26.2, 14.8, 6.7, and 4.0, respectively), which in turn was higher than that of group B (7.0, 4.2, 2.4, and 1.8, respectively). Differences were statistically significant among all groups and for all thresholds. CONCLUSIONS: Irregularity of the stromal bed after any dissection can be quantified using the Canny method. The use of an automated microkeratome for DSAEK reduces irregularity and helps obtain a surface more similar to that obtained with DMEK than with a manual microkeratome.

Label-free LC-MS/MS quantitative analysis of aqueous humor from keratoconic and normal eyes.

PURPOSE: The etiology of keratoconus (KC) and the factors governing its progression are not well understood. It has been suggested that this disease might be caused by biochemical alterations in the cornea; changes in the expression profiles of human aqueous humor (hAH) proteins have been observed in some diseases. To gain a new insight into the molecular mechanisms of KC pathology, we examined the hAH proteomes of those in the advanced stages of this disease. We used a high-throughput mass spectrometry approach to compare hAH protein expression in patients with KC and in control subjects. METHODS: Aqueous humor samples were acquired from five keratoconus patients during keratoplasty surgery and from five myopic control subjects during phakic intraocular lens implantation. Quantitative mass spectrometry analysis using spectral counting was performed to determine the relative amounts of hAH proteins in the samples from KC patients and control individuals. RESULTS: All KC patients included in the study presented severe keratoconus (K2 >52 D), and slit-lamp examination revealed microfolds in Descemet's membrane, without clinical signs of hydrops. We found significant differences between the expression levels of 16 proteins in the two groups. In KC samples, seven proteins were overexpressed and nine were underexpressed in comparison with the control group. Gene ontology analysis revealed that these deregulated proteins are implicated in several biologic processes, such as the regulation of proteolysis, responses to hypoxia, and responses to hydrogen peroxide, among others. CONCLUSIONS: The protein expression profiles in hAH from KC patients and myopic control subjects differ significantly. This result suggests that some components of the hAH proteome are involved in this disease. Further in-depth analysis of the hAH proteome should provide a better understanding of the mechanisms governing the pathophysiology of KC.

Development of a nomogram to achieve ultrathin donor corneal disks for Descemet-stripping automated endothelial keratoplasty.

PURPOSE: To report the predictability of a nomogram for ultrathin donor lamella creation for Descemet-stripping automated endothelial keratoplasty (DSAEK) with an automated microkeratome. SETTING: Instituto de Oftalmología La Arruzafa, Córdoba, Spain. DESIGN: Prospective nonrandomized consecutive case series. METHODS: This study enrolled eyes of consecutive patients in which DSAEK was performed to treat Fuchs dystrophy or bullous keratopathy. Patients with macular pathology or other vision-limiting pathology were included. The same surgeon performed all surgeries using an automated keratome (Amadeus II) linked to an artificial anterior chamber. The target donor lamella thickness was from 70 to 120 µm based on a nomogram that incorporates advancement speed, blade holder size, and corneal thickness. The decimal corrected distance visual acuity (CDVA) at 3 months postoperatively, graft thickness at 1 month, and complications were recorded. RESULTS: Fifty-one patients (60 eyes) were enrolled. One month postoperatively, the mean donor lamella thickness was 99.33 µm ± 16.97 (SD) (range 67 to 130 µm). The target thickness range was achieved in 96.66% of cases (58 eyes). In 32 patients with a potential visual acuity of 20/20, the mean postoperative CDVA was 0.80 ± 0.16 (range 0.55 to 1.20). There were no complications during flap preparation, intraoperatively, or postoperatively and no events caused donor corneal tissue to be discarded. CONCLUSIONS: The use of a nomogram with an automated microkeratome for DSAEK provided good visual outcomes with a thin donor lamella (≤120 µm). The outcomes with the nomogram were similar to those reported for Descemet membrane endothelial keratoplasty. FINANCIAL DISCLOSURE: Neither author has a financial or proprietary interest in any material or method mentioned.

Candida keratitis after Descemet stripping with automated endothelial keratoplasty.

PURPOSE: To report a case of Candida albicans keratitis after Descemet stripping with automated endothelial keratoplasty (DSAEK) due to fungal contamination of the donor cornea. METHODS: Case report. RESULTS: A 73-year-old woman underwent phacoemulsification with intraocular lens (IOL) implantation and DSAEK with 1 week difference. Ten days after DSAEK surgery, the culture of the donor corneoscleral rim revealed Candida albicans contamination and a small whitish infiltrate was noted within the interface. Despite conservative treatment with oral and systemic voriconazole, the infection was present outside the interface and inside the anterior chamber. Hot penetrating keratoplasty (PKP) was performed and the infection was eradicated. However, due to uncontrolled high intraocular pressure, a new PKP had to be performed, the IOL was removed, and an Ahmed valve was implanted (by pars plana vitrectomy). The anterior cap of the same donor cornea was used to perform a tectonic superficial anterior lamellar keratoplasty and the recipient did not have any problem related to fungal infection. CONCLUSIONS: The diagnosis of fungal keratitis should be taken into account once a small infiltrate is seen in the interface of any kind of lamellar keratoplasty. It is not clear whether it is better to treat it conservatively or aggressively.

Endothelial cell loss after pars plana vitrectomy in patients with previous endothelial keratoplasty.

PURPOSE: To describe the changes in endothelial cell density after pars plana vitrectomy (PPV) in patients with previous Descemet stripping with automated endothelial keratoplasty (DSAEK). METHODS: Pars plana vitrectomy was performed in 3 eyes after DSAEK (16, 14, and 7 months, respectively). Two patients had a retinal detachment and the third patient had an epiretinal membrane. The cell population density and corrected distance visual acuity (CDVA) were measured before and after PPV. RESULTS: Two months after PPV, the average endothelial cell loss was 11.12% (range 10.3%-12.15%). One patient lost 2 lines of CDVA and the other 2 patients lost only half a line of Snellen CDVA. CONCLUSIONS: Patients who have undergone DSAEK may experience accelerated endothelial cell loss after a subsequent PPV procedure but the extra cell loss should not pose a short-term risk to graft viability unless the endothelial cell density was already borderline.

Comparison of custom ablation and conventional laser in situ keratomileusis for myopia and myopic astigmatism using the Alcon excimer laser.

PURPOSE: To compare the refractive outcomes, higher order aberrations, and contrast sensitivity after laser in situ keratomileusis (LASIK) using wavefront ablation and conventional ablation. SETTING: Private practice in Córdoba, Spain and a free-standing outpatient surgery center. METHODS: This was a prospective, nonrandomized, observational case series comparing outcomes of 239 eyes that underwent LASIK for myopia and myopic astigmatism with either wavefront or conventional ablation using the LADARVISION excimer laser. Manifest refractive sphere ranged from 0.50 D to -8.00 D with astigmatism up to -4.00 D. Eighty-nine eyes underwent conventional LASIK (conventional group), and 150 eyes underwent custom ablation (custom group). Refractive outcomes, ocular higher order root mean square (HOA-RMS), and contrast sensitivity were tested for statistically significant differences between groups. A P-value less than 0.05 was considered statistically significant. Six month postoperative data are reported here. RESULTS: Postoperatively, the mean SE was -0.03 D +/- 0.19 D for the custom group, and -0.14 D +/- 0.35 D for the conventional group (P = 0.003). Ninety-nine percent of the eyes in the custom group, and 92% of the eyes in the conventional group were within 0.50 D of the intended correction (P > 0.05). The HOA-RMS was 0.16 mum lower in the custom group (P < 0.001). Contrast sensitivity was statistically significantly better at 3 cycles per degree (cpd) (P < 0.001) and 6 cpd (P = 0.009) in the custom group. CONCLUSION: There was a statistically significant lower induction of HOA-RMS and better predictability and contrast sensitivity in eyes that underwent custom ablation with the LADARVISION excimer laser.

Description, etiology, and prevention of an outbreak of diffuse lamellar keratitis after LASIK.

PURPOSE: To describe an outbreak of diffuse lamellar keratitis (DLK) and provide a hypothesis about the etiology. METHODS: A retrospective analysis was carried out on 328 eyes of 220 patients who underwent LASIK over 9 months. The occurrence of DLK using two different methods of cleaning and sterilizing surgical instruments and an autoclave reservoir were analyzed. Microbial analyses were carried out by two laboratories on samples obtained from the original autoclave reservoir and tubing. A chi-square test was used to compare qualitative values. The Student t test was used to compare numerical values. RESULTS: Forty-six (24.5%) of 188 cases of DLK were diagnosed. Sphingomona paucimobilis and Burkholderia pickettii were isolated in the reservoir of the steam sterilizer. Electron microscopy revealed gram-negative microbes on the tubing walls. After changing the reservoir of the steam sterilizer and implementing a new cleaning and sterilization protocol based on air-drying the instruments and draining and drying the reservoir of the sterilizer, the occurrence of DLK stopped. No statistically significant correlation was noted between the occurrence of DLK and gender, age, or volume of tissue removed. CONCLUSIONS: Data obtained during this DLK outbreak support the theory that a bacterial endotoxin, which can survive short-cycle steam sterilization, could be responsible for an outbreak of DLK. We recommend cleaning and sterilization protocols based on air-drying surgical instruments and leaving the reservoirs completely dry at the end of each surgical day.

Deep anterior lamellar keratoplasty in post-laser in situ keratomileusis keratectasia.

We describe a technique using deep anterior lamellar keratoplasty (DALK) in 5 eyes that developed keratectasia after LASIK. The technique is based on surgical manipulation that allows visualization of the lamellar dissection depth using a posterior approach to reach the predescemetic space. The mirror effect, indentation effect, and folding effect were used to determine proximity to Descemet's membrane. The same diameter donor and recipient buttons were used to correct myopia. The donor button without Descemet's membrane was placed using 10-0 nylon sutures. No intraoperative or postoperative complications occurred. The mean best spectacle-corrected visual acuity changed from 0.16 diopter (D) +/- 0.05 (SD) (range 0.10 to 0.25 D) before DALK to 0.68 +/- 0.19 D (range 0.5 to 1.0 D) after DALK. Deep anterior lamellar keratoplasty may be a better alternative than penetrating keratoplasty for any pathology with healthy endothelium.