A randomised controlled trial comparing femtosecond laser-assisted cataract surgery versus conventional phacoemulsification surgery: 12-month results.

AIMS: To report 12-month outcomes of randomised controlled trial comparing conventional phacoemulsification surgery (CPS) with femtosecond laser-assisted cataract surgery (FLACS). METHODS: This was a single-centre, prospective single-masked randomised case-controlled trial. Four hundred patients were randomised to CPS or FLACS with the LenSx platform (Alcon Laboratories Inc.). Visual acuity, refraction, central corneal thickness, endothelial cell loss (ECL), adverse events and quality of life outcomes, using EuroQOL 5-dimensions (EQ-5D-3 L) and cataract surgery patient-reported outcome measures (PROMs) questionnaires (Cat-PROM5), were recorded. RESULTS: Two hundred and thirty four patients (58.5%) attended 12-month follow-up (116 FLACS, 118 CPS). Mean LogMAR unaided distance visual acuity) (±SD) was 0.12 (0.18) with FLACS and 0.13 (0.19) with CPS (p=0.68; 95% Confidence Interval [CI]-0.06,0.04). Mean spherical equivalent (SE) refraction was -0.1±0.6 diopters (D) with FLACS and -0.2±0.6 D with CPS (p=0.44; 95% CI -0.09, 0.21). Mean corrected distance visual acuity (±SD) was -0.01 (0.1) with FLACS and 0(0.1) with CPS (p=0.45; 95% CI -0.04,0.02). Two patients per group underwent YAG laser capsulotomy for posterior capsular opacification (p=1). Mean ECL (per mm2±SD) was 301±320 with FLACS and 228±303 with CPS (p=0.07; 95% CI -7.26, 153.26). Mean Cat-PROM scores (±SD) were -5.5 (2.6) with FLACS and -5.8 (2.5) with CPS (p=0.3; 95% CI 0.31,1.01). EQ5-3DL mean index score (±SD) was 0.92 (0.13) with FLACS and 0.89 (0.14) with CPS (p=0.1; 95% CI -0.1, 0.01). Vector analysis comparing manual limbal relaxing incisions (LRIs) and intrastromal femtosecond laser-assisted astigmatic keratotomies (iFAKs) showed a greater correction index (p=0.02; 95% CI 0.06 to 0.60) and smaller difference vector (p=0.046; 95% CI -0.54, -0.01) with iFAK. CONCLUSIONS: There were no differences in vision, refraction, adverse postoperative events or PROMs between FLACS and CPS groups at 12 months. iFAKs may provide more effective astigmatic correction compared to LRIs, 12 months postoperatively.

A randomized controlled trial comparing femtosecond laser-assisted cataract surgery versus conventional phacoemulsification surgery.

PURPOSE: To compare the clinical results of conventional phacoemulsification surgery (CPS) with femtosecond laser-assisted cataract surgery. SETTING: Guy's & St Thomas' NHS Foundation Trust, London, United Kingdom. DESIGN: Single-center prospective randomized interventional case-controlled trial. METHODS: Patients undergoing cataract surgery were randomized to receive either CPS or femtosecond laser-assisted cataract surgery. The surgery was performed with a femtosecond laser (Lensx), and all operations were performed with a gravity-fluidics torsional phacoemulsification machine (Infiniti). The visual acuity, refraction, central corneal thickness (CCT), central foveal thickness (CFT), endothelial cell loss, and rates of intraoperative and postoperative events were recorded. Quality of life outcomes were measured with the EuroQOL 5 dimensions questionnaire (EQ-5D) and patient-reported quality of vision was assessed with a cataract surgery patient-reported outcome measures questionnaire (Cat-PROM5). RESULTS: The study comprised 400 eyes of 400 patients who had CPS (n = 200) or femtosecond laser-assisted cataract surgery (n = 200). Seven patients (3.5%) in the femtosecond laser-assisted group were not able to complete the treatment and received CPS. The mean uncorrected distance visual acuity (logarithm of the minimum angle of resolution [logMAR]) 0.15 ± 0.21 (SD) and 0.15 ± 0.19 logMAR after CPS and femtosecond laser-assisted surgery, respectively (P = 1.0); the pinhole-corrected visual acuity was 0.04 ± 0.12 and 0.04 ± 0.12, respectively (P = 1.0); the increase in CCT was 13 ± 19 µm and 15 ± 25 µm, respectively (P = .5); and the endothelial cell loss was 9.7 ± 13.7 % and 10.2% ± 13.7, respectively (P = .76). The manifest refraction spherical equivalent error was -0.14 ± 0.60 diopters (D) after CPS and -0.12 ± 0.60 D after femtosecond laser-assisted surgery (P = .74); the mean change in CFT was 9 ± 35 µm and 6 ± 35 µm, respectively (P = .55); and the rate of posterior capsule rupture was 3% and 0%, respectively (P = .03). CONCLUSIONS: This study confirms the nonsignificant differences between 2 treatment modalities, notwithstanding a significant reduction in posterior capsule ruptures in the femtosecond laser-assisted surgery group.

Refractive outcomes after limbal relaxing incisions or femtosecond laser arcuate keratotomy to manage corneal astigmatism at the time of cataract surgery.

PURPOSE: To compare the results of manual limbal relaxing incisions (LRIs) performed during conventional phacoemulsification surgery with those of nonpenetrating femtosecond laser arcuate keratotomies performed during femtosecond laser-assisted cataract surgery to manage corneal astigmatism. SETTING: Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom. DESIGN: Randomized case-controlled trial. METHODS: This was a secondary outcome of a randomized controlled trial comparing 400 patients treated with conventional phacoemulsification surgery or femtosecond laser-assisted cataract surgery. All patients with corneal astigmatism greater than 0.9 diopter (D) were offered LRIs or femtosecond laser arcuate keratotomy based on the original randomization. Visual acuity, postoperative refraction, and corneal topography were recorded 4 weeks postoperatively. Vector analysis was performed using the Alpins method. RESULTS: Fifty-one eyes of 51 patients received LRIs, and 53 eyes of 53 patients received femtosecond arcuate keratotomies. The mean target induced astigmatism was 1.50 D and 1.38 D, respectively, with 1.02 D and 1.23 D surgically induced astigmatism (P = .21), resulting in the femtosecond arcuate keratotomy group having a smaller difference vector (1.17 D versus 0.89 D; P = .02) and a greater correction index (0.48 versus 0.73; P = .02). Forty-four percent of patients in the femtosecond arcuate keratotomy group and 20% in the LRI group attained a postoperative cylinder of less than 0.50 D (P = .01). CONCLUSIONS: The femtosecond arcuate keratotomy group achieved a higher correction index and a smaller difference vector. The femtosecond arcuate keratotomy patients showed less postoperative cylinder than LRI patients.

Evaluation of a hub-and-spoke model for the delivery of femtosecond laser-assisted cataract surgery within the context of a large randomised controlled trial.

AIMS: To test a hypothesis that cataract operating room (OR) productivity can be improved with a femtosecond laser (FL) using a hub-and-spoke model and whether any increase in productivity can offset additional costs relating to the FL. METHODS: 400 eyes of 400 patients were enrolled in a randomised-controlled trial comparing FL-assisted cataract surgery (FLACS) with conventional phacoemulsification surgery (CPS). 299 of 400 operations were performed on designated high-volume theatre lists (FLACS=134, CPS=165), where a hub-and-spoke FLACS model (1×FL, 2×ORs=2:1) was compared with independent CPS theatre lists. Details of operative timings and OR utilisation were recorded. Differences in productivity between hub-and-spoke FLACS and CPS sessions were compared using an economic model including testing hypothetical 3:1 and 4:1 models. RESULTS: The duration of the operation itself was 12.04±4.89 min for FLACS compared with CPS of 14.54±6.1 min (P<0.001). Total patient time in the OR was reduced from 23.39±6.89 min with CPS to 20.34±5.82 min with FLACS (P<0.001)(reduction of 3.05 min per case). There was no difference in OR turnaround time between the models. Average number of patients treated per theatre list was 9 for FLACS and 8 for CPS. OR utilisation was 92.08% for FLACS and 95.83% for CPS (P<0.001). Using a previously established economic model, the FLACS service cost £144.60 more than CPS per case. This difference would be £131 and £125 for 3:1 and 4:1 models, respectively. CONCLUSION: The FLACS hub-and-spoke model was significantly faster than CPS, with patients spending less time in the OR. This enabled an improvement in productivity, but insufficient to meaningfully offset the additional costs relating to FLACS.

Sixteen-year follow-up of hyperopic laser in situ keratomileusis.

PURPOSE: To assess the long-term efficacy and safety of hyperopic laser in situ keratomileusis (LASIK). SETTING: Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom. DESIGN: Prospective cohort study. METHODS: Hyperopic LASIK was performed using a mechanical microkeratome, an optical zone of 6.5 mm, and a blend zone of 1.5 mm. Simple hyperopia was treated. RESULTS: The mean patient age was 51.6 years (range 34 to 60 years). Preoperatively, the mean spherical equivalent (SE) was +3.74 diopters (D) (range +1.25 to +6.50 D). The mean attempted correction was +3.64 D (range +1.5 to +6.0 D). The mean follow-up was 16.5 years. The mean SE was +0.28 D (range -1.0 to +1.5 D) at 12 months, +0.84 D (range -0.75 to +3.35 D) at 5 years, and +1.74 D (range -0.75 to +4.13 D) at 16 years, representing an increase in hyperopia of +1.47 D ± 1.43 (SD) between 1 year and 16 years (P < .0001) and of +1.13 ± 0.8 D between 5 years and 16 years (P < .03). The uncorrected distance visual acuity improved at 16 years (P < .0001); corrected distance visual acuity (CDVA) was unchanged (P < .2). The efficacy index was 0.5 and the safety index, 1.09. One eye (3%) lost 2 lines of CDVA. Keratometry remained stable between 1 year and 16 years (P < 1.0). Four eyes (12%) had cataract surgery, and 2 (6%) had laser iridotomy. There was no ectasia. CONCLUSIONS: After hyperopic LASIK, an increase in hyperopia occurred between 1 and 5 years and 16 years. At 16 years, efficacy was limited but with no sight-threatening complications. FINANCIAL DISCLOSURES: Dr. Marshall was a consultant to Summit Technology, Inc. Dr. O'Brart holds a noncommercial research grant from Alcon Laboratories, Inc. None of the other authors has a financial or proprietary interest in any material or method mentioned.

Eighteen-year follow-up of hyperopic photorefractive keratectomy.

PURPOSE: To investigate the long-term efficacy of hyperopic photorefractive keratectomy (PRK). SETTING: University Hospital, London, United Kingdom. DESIGN: Prospective case series. METHODS: Patients with a follow-up of 18 years ± 0.7 (SD) attended for examination. All had spherical corrections with a 6.5 mm optical zone and 1.5 mm blend zone. RESULTS: Twenty-five patients (45 eyes) were included. The mean preoperative spherical equivalent (SE) refractive error was +4.11 ± 1.8 diopters (D) (range +1.125 to +7.25 D). Between 1 year and 18 years, in eyes that had no cataract surgery (n = 34), there was a +1.14 ± 1.48 D increase in the mean SE (P < .0002). The increase between 7.5 years and 18.0 years did not reach clinical significance (P = .1). Uncorrected distance visual acuity improved at 18 years (P < .02). Corrected distance visual acuity (CDVA) was reduced (P < .001). The efficacy index was 0.47, and the safety index was 0.83. Six eyes (18%) lost 2 lines of CDVA, of which 4 eyes had preexisting cataract. Keratometry remained stable between 1 year and 18 years (P = .2). Forty percent still had traces of peripheral haze, and 4 (9%) had Salzmann-like changes. Eleven eyes (24%) had cataract surgery and 4 (9%) had laser iridotomy. There was no evidence of ectasia. CONCLUSIONS: Hyperopic PRK showed an increase in hyperopic SE between 1.0 year and 7.5 years but was generally stable thereafter. The efficacy was limited. Peripheral haze was evident in 40% of cases with Salzmann-like changes in some. Ocular comorbidity in relationship to cataract was common and reduced CDVA. FINANCIAL DISCLOSURE: Dr. Marshall was a consultant to Summit Technology, Inc. No author has a financial or proprietary interest in any material or method mentioned.

Corneal Cross-linking to Halt the Progression of Keratoconus and Corneal Ectasia: Seven-Year Follow-up.

PURPOSE: To determine long-term efficacy and safety of riboflavin/ultraviolet A corneal cross-linking (CXL). DESIGN: Prospective cohort study. METHODS: Thirty-six patients (36 eyes) who underwent epithelium-off CXL at a University Hospital (Guy's and St Thomas' National Health Service Foundation Trust) 6-8 years previously were examined. The main outcome measures were refractive error, visual acuity, corneal topographic keratometry, ultrasonic pachymetry, and topography-derived corneal wavefront. RESULTS: At 7 years compared to preoperative values, mean spherical equivalent refractive error (SEQ) increased by +0.78 diopter (D) (P < .005) and mean simulated topographic keratometry (SimK) and mean maximum keratometry (Kmax) reduced by -0.74 D (P < .0001) and -0.91 D (P < .0001), respectively. Uncorrected distance acuity (UCDA) (P < .0005) and corrected distance acuity (CDVA) (P < .0001) had improved and root mean square (RMS) (P < .0005), coma (P < .0005), and secondary astigmatism (P < .005) lessened. At 7 years compared to 1 year, CDVA improved (P < .05); mean SimK (P < .0005) and mean Kmax (P < .005) reduced by -0.45 D and -0.56 D, respectively; and RMS (P < .0005) and coma (P < .0005) decreased. At 7 years compared to 5 years, CDVA improved (P < .05) and trefoil reduced (P < .05). No treated eyes progressed. In 29 initially untreated fellow eyes mean SimK increased by +0.54 D (P < .02), mean Kmax by +0.87 D (P < .05), and refractive astigmatism increased (P < .0005). CONCLUSIONS: Following corneal cross-linking, improvements in topographic and wavefront parameters evident at 1 year were seen to continue to improve at 5 years and were maintained at 7 years. No treated eyes progressed over the 7-year follow-up period.