Health Policy Advisory Committee on
Technology
Technology Brief Update
Femtosecond lasers for cataract surgery
February 2014
© State of Queensland (Queensland Department of Health) 2014
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TECHNOLOGY BRIEF UPDATE
Technology, Company and Licensing
Register ID WP059
Technology name Femtosecond lasers for cataract surgery
Patient indication For the removal of the crystalline lens in patients undergoing cataract surgery
Stage of development in Australia
Yet to emerge Established
Experimental Established but changed indication or modification of technique
Investigational Should be taken out of use Nearly established
Australian Therapeutic Goods Administration approval
Yes ARTG number(s) Multiple Femtosecond ophthalmic Yb: Glass laser system were identified from TGA 181017 LenSx (Alcon Laboratories Australia Pty Ltd) 194204 Optimedica (Designs for Vision AustPty Ltd) 195792 Technolas (Emagin Pty Ltd)
203169 LensAR (IQ Medical)
209634 VICTUS (Bausch & Lomb Australia Pty Ltd) 212196 AMO (AMO Australia Pty Ltd)
No
Not applicable
It is not entirely clear regarding the exact degree of diffusion of the technology
internationally. Personal communication from one manufacturer indicates that the diffusion of femtosecond laser technology is largely confined to the private sector.
According to the information provided by one manufacturer, there are a total of 22 units of different femtosecond systems in the process of being installed in Australia, all in private sector: 16 LenSX®, 4 Optimedica®, 1 LensAR® and 1 VICTUS®. In addition, two femtosecond laser systems have been installed in New Zealand (1 LenSx® and 1 LensAR®).
International utilisation
Country Level of Use
Trials underway or completed
Limited use Widely diffused
Australia √ New Zealand √ Austria √ Czech Republic √ France √ Germany √ Hungary √ India √ Korea √ USA √
2014 Evidence and Policy 2014 Safety and effectiveness
Since the initial brief on femtosecond laser-assisted cataract surgery (FLACS), a large number of studies have been published. For the purpose of this update, only prospective comparative studies, comparing FLACS with conventional cataract surgery, with a sample size of > 100 eyes were included. However, these criteria were relaxed for Australian studies due to their relevance to local context. It is important to note that currently FLACS reflects an independent pre-treatment procedure undertaken prior to cataract surgery, which otherwise would proceed as per normal.
Australian study
Abell et al investigated the safety and effectiveness of FLACS using Catalys (Optimedica, Santa Clare, USA) system, compared with conventional cataract surgery, in a prospective cohort study including 400 consecutive patients in Australia (level III-2 interventional evidence).1 Patients were excluded if aged less than 22 years, had extensive corneal scarring, corneal ring insertion, past glaucoma filtration surgery or previous refractive surgery. The laser procedure started with anterior capsulotomy followed by lens
fragmentation, with surgery completed with the standard phacoemulsification procedure. Corneal incision was not performed by laser. Baseline demographic and cataract
characteristics were similar between the two groups, with a mean age of 73.3 ± 9.9 years (vs 71.8 ± 10.8 years in the conventional treatment group) and mean cataract grade of 2.81 ± 0.82 (vs 2.71 ± 0.72 in the conventional group) for patients in the FLACS group. Patients were followed up at day one, day two and three weeks post-surgery. All 200 cases in the
FLACS group successfully completed capsulotomy, although treatment was stopped during lens fragmentation in four patients and they subsequently received conventional surgery. Intention-to-treat analysis was performed. A statistically significant reduction in mean effective phacoemulsification time (EPT) of 70 per cent (p < 0.0001) in the FLACS group (4.3 seconds) compared to the conventional group (14.3 seconds) was reported (Figure 1).
Figure 1 Scatter plot of mean effective phacoemulsification time (EPT) between groups.
Twenty-six patients (13%) in the FLACS group received no phacoemulsification compared to only one patient in the conventional group, and lower phacoemulsification times were observed consistently across the FLACS group (Table 1).
Table 1 Number of patients with low phacoemulsification times in both groups1
Mean EPT FLACS group
N (%) Conventional group N (%) < 4 seconds 108 (54.0) 1 (0.5) < 2 seconds 70 (35.0) 1 (0.5) < 0.5 seconds 41 (20.5) 1 (0.5) < 0 seconds 26 (13.0) 1 (0.5)
EPT=effective phacoemulsification time; FLACS= femtosecond laser-assisted cataract surgery
The reduction was similar for all grades of cataract (results not reported). This represents a significant reduction in ultrasound energy required in the eye, with the perceived benefits of decreased post-operative complications such as corneal endothelial cell loss and cystoid macular oedema. There were no anterior capsular tags or tears in either group, and one case of posterior capsule rupture with retained nucleus in each group. No significant difference in the post-operative central macular thickness based on the optical coherence tomography (OCT) was found between the groups at one week and one month, however long-term follow up data were not available. No other direct complications of femtosecond laser treatment were reported in the study. In addition, the study also reported results on
femtosecond laser treatment learning curve. Compared with the initial 100 cases, a significant reduction in femtosecond vacuum time was detected in the subsequent 100 cases (3:09 ± 0:51 vs 4:09 ± 1:11 mins, p<0.0001). Bubbles on the objective lens appeared more frequent during the second 100 cases (p=0.01). Mean EPT in the second 100 cases was longer (4.75 ± 5.22 vs 3.52 ± 4.18 seconds in the initial 100 cases, p=0.067), although the difference was not statistically significant.
The authors concluded that FLACS appeared to be as safe as conventional cataract surgery in the short term and resulted in significant shorter phacoemulsification time. It may provide the opportunity to further reduce the post-operative complications, however further study is needed to investigate the long term safety outcomes.
Another study by the same authors compared the EPT and the associated effect on visual outcomes and endothelial cell loss in 150 cases undergoing FLACS (Catalyst, OptiMedica) and 51 cases undergoing conventional phacoemulsification (level III-2 interventional evidence).2 All the procedures were performed by a single surgeon with prior experience with femtosecond laser platform. Similar exclusion criteria, pre- and post-operative
assessments and treatments, and surgical procedures were applied as in the previous study by Abell et al.1 There were no differences between the two groups in the demographic and other characteristics at baseline. The study did not find any significant between-group differences in mean post-operative best-corrected visual acuity, intraocular pressure (IOP), mean auto-refraction, mean absolute error of spherical equivalent at three weeks. Mean EPT was significantly shorter in the FLACS group compared with the conventional group, resulting in an 84 per cent reduction (14.24 ± 10.90 vs 2.33 ± 2.28 seconds, p<0.0001, respectively) and the reduction was significant for all cataract grades (p<0.01). There were 45 (30%) cases in the FLACS group with 0 EPT compared to no case in the conventional group (p<0.0001). There were no cases of wound burn, wound leak, iris trauma or IOL decentration at one day and three weeks post-surgery, and no cases of cystoid macular oedema three weeks post-surgery in either group. However a significantly less reduction in the mean endothelial cell loss in the FLACS group (-143.8 ± 208.3) than in the conventional group (-224.9 ± 188.95) at three weeks was detected (p=0.022). The study concluded that a significant reduction in phacoemulsification energy was possible by femtosecond laser treatment and this may lead to decreased corneal endothelial cell loss and corneal oedema in the early postoperative phase, resulting in faster visual recovery.
Two additional publications from the similar group of authors also reported on the
comparative safety of FLACS (Catalyst, OptiMedica) and conventional cataract surgery. One study compared the post-operative ocular inflammation using anterior chamber aqueous flare measured with laser flare photometry after FLACS (n=100) with that after conventional cataract surgery (n=76) in consecutive patients who were older than 18 years and
interventional evidence).3 Patients were excluded if they had a pre-operative flare of more than 15 photons per millisecond (ph/ms) without pharmacological pupil dilation and a range of clinical or pathological conditions that may confound the measurements. The anterior chamber flare was measured by an investigator blinded to patient’s treatment group within one week pre-operatively and one day and four weeks post-operatively. Standard
treatments were given to all patients and standard surgical procedures were followed according to their assigned groups. The two groups were similar in baseline characteristics. The study found significant differences in the mean aqueous flare post-operatively both at day one (16.6 ± 8.9 vs 21.8 ± 12.0 ph/ms, p=0.0089) and four weeks (11.1 ± 8.1 vs 14.6 ± 10.7 ph/ms, p=0.003) for FLACS and conventional groups respectively (Figure 1). Similarly, a significantly shorter mean EPT was found in the FLACS group (0.94 ± 3.47 vs 6.5 ± 4.3 seconds in the conventional group, p<0.0001). There was no difference in IOP between the groups at one day post-surgery. At four weeks post-surgery, a significantly larger increase in mean outer zone retinal thickness on OCT was found in FLACS group, however no between-group difference in change in central macular thickness and inner zone retinal thickness from baseline was found. The authors concluded that femtosecond laser treatment resulted in reduced post-operative ocular inflammation measured by aqueous flare and a lower risk for subclinical (OCT) outer macular oedema, which appeared to be due to the reduction in phacoemulsification energy in the femtosecond group.
Figure 2 Mean aqueous flare in the laser group and manual group 1 day and 4 weeks after cataract surgery (ph/ms = photons per millisecond)
Another large study compared the incidence of anterior capsule tears after FLACS and phacoemulsification cataract surgery (PCS) in a prospective, multicentre study (level III-2 interventional evidence).4 The study included 1,626 consecutive patients undergoing FLACS (n=804) or PCS (n=822), through patient self-selection, by two surgeons in two centres in Australia from April 2012 to June 2013. All patients had standard pre-operative assessments and surgical procedures according to their respective groups they were assigned to. Patients in the FLACS groups underwent laser procedures, including anterior capsulotomy and lens fragmentation, before completing with a standard phacoemulsification and an IOL
implementation. Baseline demographic and eye characteristics were comparable between the two groups. The study found a significantly higher incidence of anterior capsule tears in the FLACS group (1.87%, n=15) than in the PCS group (0.12%, n=1) (p=0.0002). All cases in the FLACS group occurred with complete capsulotomy and none were determined to have risk factors for capsule complications after reviewing pre-operative clinical notes. In seven patients, the anterior capsule tear extended to the posterior capsule and required sulcus IOL implantation, two of which underwent an anterior and posterior vitrectomy each due to vitreous loss.
In a separate analysis, the study assessed the ultrastructural features of anterior capsulotomy specimens, using scanning electron microscopy (SEM), obtained from 50 patients (40 from FLACS and 10 from PCS group) from four centres using three different laser systems (Catalyst, LenSx and LensAR). Standard sample collection and preparation methods and imaging software were used to reduce variations and inaccurate
measurements. The SEM samples from the FLACS group showed irregular capsule margin and multiple apparently misplaced laser perforations in normal parts of the tissue, which extended well inside the capsule edge. The specimens from the PCS group did not reveal any imperfection. The variations related to the different laser systems, the surgical
techniques, the surgeons, and patients’ characteristics may all affect the architecture of the capsulotomy edge. Although the small risk of complications may be offset by the potential demonstrated improvement in surgery outcomes, further studies may be required to assess such outcomes. The authors cautioned that laser anterior capsulotomy integrity may be compromised by post-stamp perforations and additional aberrant pulses, possibly because of fixation eye movements, which may lead to an increased anterior capsule tears.
International study
Filkorn and colleagues conducted a small randomised controlled trial (RCT) to compare the IOL power calculation and refractive outcome between 77 eyes (77 patients) undergoing FLACS (LenSx, Alcon) and 57 eyes (57 patients) undergoing conventional cataract surgery in Hungary and Germany (level II interventional evidence).5 Patients were excluded if they had previous ocular surgery, corneal diseases such as keratoconus, known zonular weakness, corneal astigmatism > 3.00 diopters (D), anterior capsule tear, posterior capsule rupture, severe macular disease, and amblyopia. There was no difference in baseline characteristics between the two groups. Patients in the FLACS group underwent a laser procedure including clear corneal laser incision, capsulorrhexis and cross-shaped nucleus fragmentation, prior to the phacoemulsification and implementation of an IOL. All operations were performed by a single surgeon. IOL calculation was performed with third-generation IOL formulas, and refractive outcome was measured 6-12 weeks after surgery using mean absolute error (MAE: difference between predicted and achieved postoperative spherical equivalent refraction). At 6-12 weeks after surgery, MAE was significantly lower in the FLACS group
compared to conventional group (a difference of - 0.12D, p=0.04) after adjusting for axial length and IOL type (Table 2). However the clinical significance of the improvement is questionable. There were no significant differences in corrected distance visual acuity (CDVA) and mean error between the groups. As shown in Figure 3, significant correlation was found between IOL axial length and MAE in the conventional group (r=0.14, p=0.011), whereas no correlation was found for the FLACS group. The differences in MAE between the two groups were largest in eyes with either short (<22 mm) or long (>26 mm) axial length, both favouring the FLACS group. The study concluded that femtosecond laser cataract surgery led to significantly better predictability of IOL power calculation than conventional surgery, possibly due to a more precise capsulorrhexis resulting in a more stable IOL position. It should be noted that a couple of study authors are the consultants of the manufacturer.
Table 2 Main postoperative outcomes (mean ± SD)5
FLACS group (n=77) Conventional group (n=57) Follow-up (week) 9.72 ± 2.82 9.67 ± 2.66 CDVA 0.03 ± 0.06 0.02 ± 0.04 MAE (D) 0.38 ± 0.28 0.50 ± 0.38 ME (D) -0.03 ± 0.47 0.07 ± 0.63
CDVA = corrected distance visual acuity; FLACS=femtosecond laser-assisted cataract surgery; MAE = mean absolute error; ME = mean error; SD = standard deviation
Figure 3 Correlation between axial length (AL) (Lenstar LS900) and mean absolute error (MAE) following femtosecond laser refractive cataract surgery group and conventional group5
Reddy et al conducted another small RCT to determine whether femtosecond laser-assisted lens fragmentation reduces the duration of ultrasound energy during phacoemulsification and to compare the safety of FLACS (VICTUS, Bausch & Lomb Technolas) with that of manual surgery in India (level II interventional evidence).6 Similar but stricter exclusion criteria as
those in the Filkorn study5 were applied, which included previous ocular surgery, a range of corneal diseases, disorders of ocular muscle, wound-healing disorders, autoimmune disease, and some abnormal examination results. After post-randomisation exclusion of 12 patients (8 in FLACS and 4 in conventional group) to ensure equal cataract grade distribution (no details given), 56 eyes in the FLACS group and 63 eyes in the conventional surgery group were included in the final analysis. All patients underwent standard preoperative
examinations and the respective procedures, and four surgeons in a single centre performed the procedures. Patients in the FLACS group underwent a laser procedure including anterior capsulotomy and lens fragmentation of a chosen pattern (cross only, ring only, quadrant only or a combination), prior to the phacoemulsification and implementation of an IOL. The primary outcome was the EPT. Baseline demographic and eye characteristics were similar in the two groups. The study found a significantly lower mean EPT in the FLACS group (5.2 ± 5.7 vs 7.7 ± 6.0 seconds in the conventional group, p=0.025). As shown in Figure 4, the distribution of EPT differed significantly between the two groups in the lower EPT categories (p=0.001), however the mean phacoemulsification time did not differ between the groups. There was also a significant between group difference in the mean phacoemulsification energy (13.8 ± 10.3% in the FLACS vs 20.3 ± 8.1% in the conventional group, p<0.001). Only minor complications were detected at the day of surgery with significantly higher incidence of decentred capsulotomy and IOL in the conventional group (p<0.01). No adverse events were observed in either group one day post-operation. Two cases of abnormal fundus examinations were noted in the conventional group but these were deemed unrelated with the study. The authors concluded that FLACS reduced the EPT and average
phacoemulsification energy and achieved precise and reproducible capsulotomy. Caution should apply to the interpretation of the study results due to the small number of patients. In addition, most authors either received travel and research grants from, or are employed by the manufacture.
Figure 4 Cumulative percentage of eyes by EPT (EPT=effective phacoemulsification time)6
In another small RCT, Conrad-Hengerer et al evaluated the impact of FLACS on endothelial cell loss and corneal thickness three months after surgery compared to conventional surgery in Germany (level II interventional evidence).7 The study randomised each eye of each
patient (a total of 146 eyes in 73 patients) into either FLACS or conventional group, both with IOLs implantation. Patients were excluded if aged < 22 years, had history of serious coexistent ocular disease, uncontrolled glaucoma, optic atrophy or ocular tumours, use of topical or systemic steroids or nonsteroidal anti-inflammatory drugs during the prior three months, relevant corneal opacities, poorly dilating pupils (pupil size ≤ 6 mm), known zonular weakness. Standard pre- and post-operative management was used. Femtosecond laser treatment (Catalyst, Optimedica) was applied before phacoemulsification and IOL
implementation, and all the procedures were performed by a single experienced surgeon. The two groups were similar in baseline characteristics, including Lens Opacities
Classification System III (LOCS III) grades (Table 3). The study found a mean EPT of 0.0±0.1 seconds in the FLACS group and 1.4±0.1 seconds in the conventional group. 64.4 per cent of patients in the FLACS group had an EPF of 0 seconds compared with no patients in the conventional group. Three months postoperative, significant less endothelial cell loss (41%, p<0.001) was found in the FLACS group compared to the conventional treatment group, with a relatively high mean cell loss of 8.1 ± 8.1 and 13.7 ± 8.4 per cent in the two groups respectively. The mean relative change in corneal thickness three months from the preoperative values was 3.3 ± 1.7 per cent in the FLACS group and 3.2 ± 1.4 per cent. In addition, the study showed that both endothelial cell loss at three months (r=0.433) and CDVA one week (r=0.167) after surgery were positively correlated with the EPT. There was no intraoperative adverse event in FLACS group and one anterior capsule tear occurred in the conventional group. Postoperatively, five eyes (2 in FLACS and 3 in conventional group) developed clinically significant macular oedema with a reduction in CDVA and two eyes in conventional group developed subclinical macular oedema although all improved after treatment. The authors concluded that the FLACS did not add to endothelial cell damage caused by cataract surgery and therefore might be beneficial in eyes with preoperative low endothelial cell counts. Note that one of the authors is a member of the medical advisory board of the manufacturer.
Table 3 Lens Opacities Classification System III grades and EPT by group7
LOCS III FLACS group (n=73)
Conventional group (n=73) Eyes (n) EPT (s, mean±SD)
NO1 1 0 1 0.12
NO2 17 0.00±0.00 18 0.32±0.22
NO3 31 0.02±0.03 30 1.17±0.69
NO4/4+ 24 0.09±0.15 24 2.50±1.07
FLACS=femtosecond laser-assisted cataract surgery; EPT = effective phacoemulsification time; LOCS III=Lens Opacities Classification System III; NO = nuclear opalescence
Another prospective trial compared the effect of FLACS (Catalyst, OptiMedica) in 57 eyes with that of conventional cataract surgery in 52 eyes on EPT (level III-2 interventional
evidence).8 Same exclusion criteria as those used in the RCT by Conrad-Hengerer et al7 were applied to the study population. Femtosecond laser treatment was applied before
phacoemulsification and IOL implementation, and all the procedures were performed by a single experienced surgeon. Patients in the FLACS group were slightly younger (median age 70 ± 11 years vs 72 ± 8 years in the conventional group) and had a tendency toward more dense cataracts (28 patients with nuclear opalescence (NO) grade 4 or higher vs 21 patients in the conventional group). Overall EPT was significantly lower in the FLACS group compared to the conventional group (0.16 ± 1.21 vs 4.07 ± 3.14 seconds respectively). Similar results were seen when EPT was compared according to preoperative LOCS III grading (Table 4). No phacoemulsification was needed in 26 per cent of the eyes in the FLACS group. No adverse intra- or postoperative events occurred and within four weeks of follow-up. The authors concluded that the use of femtosecond laser in cataract surgery led to a reduction in EPT compared to conventional surgery.
Table 4 Effective phacoemulsification time (seconds) by group8
LOCS III FLACS group (n=57) Conventional group (n=52) NO2 0.02±0.05 1.96±1.29 NO3 0.10±0.16 3.32±1.83 NO4/4+ 0.24±0.25 6.21±3.68
FLACS=femtosecond laser-assisted cataract surgery; LOCS III=Lens Opacities Classification System III; NO=nuclear opalescence
2014 Economic evaluation
Abell and Vote performed a cost-effectiveness analysis (CEA) of femtosecond laser cataract surgery (LCS) and conventional phacoemulsification cataract surgery (PCS), based on a hypothetical cohort of patients between six months and one year after surgery in Australia.9 Complication rates and effectiveness data (visual acuity) were obtained from a systematic literature review and the authors’ experience using LCS, and costs were estimated from a number of sources including Medicare Benefits Scheme schedule fees, Australian Medical Association recommended fees, national hospital cost data collection reports, private health insurance company annual reports, and current industry standards. The analysis made conservative estimates on the complication rates after LCS to allow the most favourable CEA. This means if LCS fails to achieve these favourable estimates then cost effectiveness would be even worse than modelled. Visual acuity was converted to utility values based on previously used formula in the literature.
In the decision model, it is assumed that 85 per cent of eyes achieved a best-corrected visual acuity (BCVA) of ≥ 6/12 after PCS (resulting in a post-cataract surgery utility of 0.978), whereas 90 per cent (a 5% improvement from PCS) of eyes achieved BCVA of ≥ 6/12 after LCS, leading to a utility of 0.985. The estimated overall weighted average cost of PCS was AU$3,522 and that of LCS was AU$4,587, assuming a capital cost laser machine of
AU$600,000, a maintenance cost of AU$50,000 per annum with 1,000 LCS performed per annum. The result of the base-case analysis was presented in Figure 5. Compared to PCS, LCS was associated with a much higher cost and only a small incremental gain in QALY (0.06), resulting in an ICER of $92,862/QALY, which indicates that LCS is not cost-effective under current cost to patients arrangements.
Figure 5 Incremental cost-effectiveness ratio (cost in Australian dollars per quality-adjusted life years) of laser cataract surgery over manual cataract surgery. LCS = laser cataract surgery; MCS = manual phacoemulsification cataract surgery; QALY = quality-adjusted life years.
A series of sensitivity analyses were performed by increasing the complication rate of LCS, altering the BCVA outcomes, decreasing the expense of LCS, reducing costs to the patients, or making LCS half as effective in improving utility. The results are presented in Table 5. Keeping the complication rates unchanged and the 5 per cent increase in BCVA outcomes, reducing the cost to patient to AU$300 resulted in an ICER of AU$56,849, which is just within the effectiveness threshold used in Australia. LCS was considered most cost-effective when 100 per cent of patients achieved a BCVA of ≥ 6/12, cost to patient was reduced to AU$300, and LCS eliminated cystoid macular oedema, corneal decompensation and lens dislocation completely. However, it would be unlikely for LCS to currently deliver this best case scenario.
Table 5 Sensitivity Analysis through differing scenarios using incremental cost-effectiveness ratios in Australian dollars (AUD) per quality-adjusted life-year
Scenario Visual acuity improvement (%)
ICER (AUD/QALY)
Baseline PCS versus no surgery NA 4,378
All complication rates differ as per model (LCS better than PCS)
Base-case 5 92,862
Better case 10 58,951
Worse case Nil 218,617
LCS “best case”: complication rates 0% (except retinal detachment), cost to patient reduced to $300
15 (maximum) 19,973
All complication rates equal (LCS=PCS)
Base case 5 177,759
Better case 10 88,651
Complication rates differ as per model, except corneal decompensation 0% in LCS
Base case 5 172,759
Better case 10 87,367
Worse case Nil 5,052,138
All complication rates differ as per model: cost to patients $300
Base case 5 56,849
Better case 10 36,089
Best case 15 25,463
ICER=incremental cost-effectiveness ratios; LCS=laser cataract surgery; PCS=phacoemulsification cataract surgery; QALY=quality-adjusted life years;
The authors emphasised that the estimated safety and effectiveness data used in the decision model are relatively favourable to LCS based on available clinical data, and the cost estimates were generally conservative and based on weighted average where appropriate. Despite this, the hypothetical benefits of LCS are not considered cost-effective at its current cost to patients. Only a reduction in the capital and/or consumable costs, thus overall cost to patient, would be likely to make it more cost-effective,but still not as cost effective as current PCS techniques.
Personal communication with the manufacture (Alcon) indicated the approximate current unit costs of the different systems as following:
LenSx: $600,000 Optimedica: $650,000
LensAR: $450,000 (list price ~$480,000) VICTUS: $600,000
Currently there is no specific MBS item number for femtosecond laser procedure. According to the cost information from the cost-effectiveness analysis, taking into account the capital cost of the laser platform and its maintenance costs (approximately $50,000 per annum), as well as the single-use disposable consumables (around $500 per eye for laser platform), the cost to patient for laser cataract surgery is currently ~$750-$1,000.9
2014 Ongoing research
A number of completed or ongoing clinical trials comparing FLACS and manual cataract surgery were identified from the ClinicalTrials.gov. The following are ongoing RCTs and cost-effectiveness studies:
NCT01982006: An economic evaluation based on a RCT of femtosecond laser
assisted cataract surgery (FEMCAT) in France. Primary outcome is the ICER based on outcomes 3-month after inclusion and QoL at multiple time points. The estimated study completion date is April 2016.
NCT01971177 (Technolas): A multicentre RCT to addressing the efficacy and safety of femtosecond-laser assisted versus manual lens fragmentation procedure in Czech Republic and India. Primary outcome is EPT. Follow-up is 1-month postoperative. The estimated study completion date is May 2014.
NCT02023437 (Technolas): A follow-up study extension to a previous RCT
(NCT01971177) to investigate the short-term (3 months) safety of femtosecond-laser assisted cataract surgery. The estimated study completion date is July 2014.
NCT01769313 (Technolas): An investigator masked RCT to investigate whether the femto-laser cataract surgery causes any significant differences in the resulting intra ocular lens overlap (ΔROverlap) in Germany. Follow-up is 6-month postoperative. The estimated study completion date is October 2014.
NCT01991717 (Technolas): An investigator-masked randomised study comparing femtosecond laser assisted with conventional phacoemulsification cataract surgery in Austria. The primary outcome is EPT during surgery. The trial is not yet started recruiting and the estimated completion data is January 2015.
NCT01878838 (Catalyst vs LenSx): A RCT comparing the intra-operative effects, safety, efficacy and performance of two laser systems in patients undergoing FLACS in the USA. The estimated study completion date is September 2013.
Other local research (level III-2) comparative cohort studies (A/ssoc. Prof. Brendan Vote) • Large multiple surgeon prospective comparative cohort study (4080 patients)
analysing operative complications and EPT between LCS (n= 1852) and PCS (n=2228) submitted for publication.
• Large multicentre prospectivecomparative cohort study (>1000 patients) assessing long term (6 months) refractive outcomes.
• Long term (6 months) corneal safety outcomes in prospective comparative cohort study.
2014 Other issues
Both Australian and international studies have indicated that FLACS technique involves a significant learning curve and initially increased complications even for the experienced cataract surgeons. Australian experience showed that a clear learning curve was reflected in the significant improvement in a range of surgery outcomes, including the number of
docking attempts, miosis after the laser procedure, free-floating capsulotomies, anterior capsule tears, posterior capsule tears, posterior lens dislocation, post-laser pupillary constriction and anterior capsule tags, among the subsequent cases as compared to the initial cases.10, 11 Surgeons’ prior experience with the use of femtosecond laser may help to flatten the learning curve.10 However there is also suggestion that a significant learning curve may extend beyond the initial cases.4 The level of uptake of the technology will ultimately be determined by further large comparative studies evaluating the clinically measurable and patient-relevant outcomes.12
It is suggested that regulatory training bodies will need to consider the standards of the training programs across different platforms due to worldwide adoption of competence-based structure. There is also concern that the development of the laser system may result in loss of surgical skills, however it should be highlighted that a competent surgeon would be essential in managing potential complications or irregularities with the laser system and the critical factors of surgical judgement and experience cannot be simply coded into the laser system. Overall FLACS may allow less-experienced surgeons to obtain better results but may fail to demonstrate a significant improvement for experienced surgeons, thus resulting in similar outcomes across the board. The implementation of FLACS may also require significant system redesign of existing cataract surgery pathways, operating theatre space, increased staff requirement and reduced patient flow, resulting in reduced system efficiency and increased costs.13
Significant financial costs are involved in the implementation of FLACS. Australian
experience indicated that currently the investment of femtosecond laser system can only be justified, from a purely business model sense, if an institution, be it an ambulatory surgical centre, a private hospital, or a public hospital, would perform approximately 500 cataract procedures per year.14 If the technology evolves and cost reduces, it may be applicable to smaller centres performing 200 to 300 procedures per year, however a realistic business model may prove to be difficult to develop. However these business models do not take into consideration whether the charges to patients are justifiable. Since this publication, a few
more femtosecond laser systems have been registered with TGA (see Australian Therapeutic Goods Administration approval section for details), however it is still too early to predict the effect of market pressures on capital and disposable costs.
The evidence in favour of femtosecond laser pretreatmentremains weak (eg. short follow-up, small numbers, lower level evidence), thus it is unlikely to have a place in the public health system in the near future (eg. next decade). Benefits are limited when compared with current PCS techniques. Nonetheless there is likely to be group of patients (more complex cases) that will experience benefit (egpatients with compromised endothelium, mature cataracts, pseudoexfoliation).
Clinician feedback indicates that, based on current evidence, this technology does not warrant either public (medicare/DVA) or health insurance funding. Nonetheless it is
appropriate for individual patients to choose (and self-fund) this additional procedure, and as such, neither government or insurers should create an additional financial barrier for patients choosing to accessfemtosecond laser pretreatment as part of their cataract procedure. To do so is unethical (egforcing a patient to pay for both femtosecond laser pretreatment and cataract surgery if they choose to self-fund the femtosecond laser
component and otherwise would be funded for their cataract surgery –eg.privately insured, DVA).
2014 Summary of findings
There are a large body of controlled studies comparing FLACS to conventional cataract surgery, including a few small RCTs, being published during the last two years. Most studies showed that FLACS increased precision and reproducibility of anterior capsulotomy,
significantly reduced the average effective phacoemulsification time and energy than in manual surgery, leading to a short-term reduction in postoperative corneal endothelial cell loss and decreased anterior segment inflammation in the early postoperative period. The femtosecond laser surgery is generally considered to be safe in short term, although there is some suggestion of increased anterior capsule tears. Little long-term outcomes are
available.
It is currently not entirely clear whether the demonstrated benefits of FLACS can be fully translate to safer, more accurate outcomes for patients as a limited number of studies have evaluated visual and refractive outcomes, with comparable outcomes being demonstrated as manual surgery. Therefore further evaluation of its effects on these patient relevant outcomes is required. At its current cost to the healthcare system and patients, the
femtosecond laser cataract surgery is not considered to be cost-effective over conventional surgery in Australian context.
The technology is continuously evolving and improving, with the potential to reduce the learning curve and intro- and postoperative complications related to FLACS. There are a
number of ongoing randomised trials and cost-effectiveness study which will provide much needed evidence on the long term and patient relevant outcomes.
2014 HealthPACT assessment
Femtosecond lasers produce a more precise cut and the time taken to emulsify the lens is shorter than that required by ultrasound. However, the operator is still required to be an experienced cataract surgeon and the number needed to treat with femtosecond lasers would need to be high to get a clinically significant improvement. Despite the diffusion of the technology in the private sector in Australia, limited long term, patient relevant outcomes are available and evidence of the cost-effectiveness of this procedure is lacking.
Therefore it is recommended that no further research on behalf of HealthPACT is warranted at this time.
2014 Included Studies
All evidence included for assessment in this Technology Brief has been assessed according to the revised NHMRC levels of evidence. A document summarising these levels may be accessed via the HealthPACT web site.
Total number of studies 9
Total number of Level II studies 3 Total number of Level IiI-2 studies 5 Total number of cost-effectiveness studies 1 2014 References
1. Abell, R. G., Kerr, N. M.&Vote, B. J. (2013). 'Femtosecond laser-assisted cataract surgery compared with conventional cataract surgery'. Clin Experiment Ophthalmol, 41 (5), 455-62.
2. Abell, R. G., Kerr, N. M.&Vote, B. J. (2013). 'Toward zero effective
phacoemulsification time using femtosecond laser pretreatment'. Ophthalmology, 120 (5), 942-8.
3. Abell, R. G., Allen, P. L.&Vote, B. J. (2013). 'Anterior chamber flare after femtosecond laser-assisted cataract surgery'. J Cataract Refract Surg, 39 (9), 1321-6.
4. Abell, R. G., Davies, P. E.et al (2013). 'Anterior Capsulotomy Integrity after Femtosecond Laser-Assisted Cataract Surgery'. Ophthalmology.
5. Filkorn, T., Kovacs, I.et al (2012). 'Comparison of IOL power calculation and refractive outcome after laser refractive cataract surgery with a femtosecond laser versus conventional phacoemulsification'. J Refract Surg, 28 (8), 540-4.
6. Reddy, K. P., Kandulla, J.&Auffarth, G. U. (2013). 'Effectiveness and safety of
femtosecond laser-assisted lens fragmentation and anterior capsulotomy versus the manual technique in cataract surgery'. J Cataract Refract Surg, 39 (9), 1297-306. 7. Conrad-Hengerer, I., Al Juburi, M.et al (2013). 'Corneal endothelial cell loss and
corneal thickness in conventional compared with femtosecond laser-assisted cataract surgery: three-month follow-up'. J Cataract Refract Surg, 39 (9), 1307-13.
8. Conrad-Hengerer, I., Hengerer, F. H.et al (2012). 'Effect of femtosecond laser fragmentation on effective phacoemulsification time in cataract surgery'. J Refract Surg, 28 (12), 879-83.
9. Abell, R. G.&Vote, B. J. (2013). 'Cost-Effectiveness of Femtosecond Laser-Assisted Cataract Surgery versus Phacoemulsification Cataract Surgery'. Ophthalmology. 10. Bali, S. J., Hodge, C.et al (2012). 'Early experience with the femtosecond laser for
cataract surgery'. Ophthalmology, 119 (5), 891-9.
11. Roberts, T. V., Lawless, M.et al (2013). 'Surgical outcomes and safety of femtosecond laser cataract surgery: a prospective study of 1500 consecutive cases'.
Ophthalmology, 120 (2), 227-33.
12. Hodge, C., Bali, S. J.et al (2012). 'Femtosecond cataract surgery: A review of current literature and the experience from an initial installation'. Saudi J Ophthalmol, 26 (1), 73-8.
13. Trikha, S., Turnbull, A. M.et al (2013). 'The journey to femtosecond laser-assisted cataract surgery: new beginnings or a false dawn?'. Eye (Lond), 27 (4), 461-73. 14. Roberts, T. V., Lawless, M.et al (2013). 'Femtosecond laser cataract surgery:
TECHNOLOGY BRIEF 2012
Register ID WP059 (nomination from South Australia) Name of Technology Femtosecond lasers for cataract surgery
Purpose and Target Group For the removal of the crystalline lens in patients undergoing cataract surgery
Stage of Development in Australia
Yet to emerge Established
Experimental Established but changed indication
or modification of technique
Investigational Should be taken out of use
Nearly established
Australian Therapeutic Goods Administration Approval
Yes ARTG number 181017
No
Not applicable International Utilisation
COUNTRY LEVEL OF USE
Trials underway or completed
Limited use Widely diffused
Australia Hungary Germany Korea United States Impact summary
Although there are several ophthalmic femtosecond laser systems on the market, there is currently only one, the LenSx laser system, listed on the Australian Register of Therapeutic Goods for cataract surgery1. The LenSx is manufactured by Alcon LenSx Inc (CA, United States) and is distributed by Alcon Laboratories Australia Pty Ltd. The technology would be made available through ophthalmic surgeons for patients who require cataract surgery. A brief describing the use of the IntraLase® femtosecond laser for creating corneal flaps during laser in situ keratomileusis (LASIK) surgery was prepared by ASERNIP-S in 2008. IntraLase®
1
Since writing this brief another ophthalmic femtosecond laser has been registered on the ARTG: the Designs for Vision Aust Pty Ltd - Femtosecond ophthalmic Yb: Glass laser system (ARTG number 194204)
was registered on the TGA (ARTG numbers 107191 and 124974), however, since that time IntraLase Corp has been taken over and these numbers are no longer current
Worldwide and in Australia, cataracts are a common cause of vision loss and blindness. The only effective corrective measure is the surgical removal of the cataract. The use of the femtosecond laser, combined with an imaging and alignment system, enables the precise removal of the cataractous lens with reduced adverse events compared to conventional phacoemulsification procedure. In addition to cataract removal, the femtosecond laser may be used to perform a refractive lens exchange procedure.
2012 Background
The lens of the eye is made up primarily of protein and water and its role is to focus light onto the retina at the back of the eye (Figure 6). Cataracts are an opaque formation that develops when the protein structure of the lens breaks down and forms clumps, with the resulting cloudy appearance preventing light from passing through the lens. This opaque formation is referred to as a cataract and may occur as a result of the natural aging process, exposure to agents including x-rays, infrared or ultraviolet light, systemic disease such as diabetes, some medications, traumatic injury or the use of corticosteroids (Taylor & Bilgrami 2010). Cataracts usually progress slowly resulting in a gradual loss of vision but may
eventually cause blindness if left untreated. Preventative measures such as wearing UV protecting glasses may slow the progression of cataracts, however the only effective treatment is the surgical removal of the cataract, usually by phacoemulsification (see comparator section).
Figure 6 Anatomy of the eye demonstrating the position of the lens, posterior and anterior chambers (printed with permission Retina Australia, Victoria)
Complications of cataract surgery include endophthalmitis, retinal detachment and posterior capsular opacification2 (PCO), which is reported to occur in approximately 20-40 per cent of patients, two to five years after cataract surgery (Merlin et al 2011; Wormstone et al 2009). Other complications that may occur include damage to the corneal endothelium due to excessive use of ultrasound energy during the phacoemulsification of hard cataracts, thermal injury to the cornea at the site of probe insertion, in addition to iris prolapse, leakage, ocular hypotension or vision-threatening intraocular infection due to poorly constructed cataract incisions (Palanker et al 2010). In a bid to reduce the number of these complications new methods of cataract removal and wound construction have been developed and are continually evolving.
LASIK has been the standard procedure for performing refractive surgical procedures for the correction of myopia, hyperopia and astigmatism. During the LASIK procedure a flap of corneal tissue is mechanically cut and folded back to allow access to the inner cornea, which is then re-shaped using an excimer laser (ASERNIP-S 2008). Complications associated with mechanical cutting led to the development of corneal procedures that utilised femtosecond lasers, which provide greater precision. The significant reduction in the number of
complications during corneal refractive surgery has resulted in the wide acceptance of femtosecond lasers for LASIK procedures. The success of the LASIK procedure has
stimulated interest in the use of femtosecond lasers for cataract surgery and it is envisaged that the precision of these lasers will reduce the complications such as those described above (Uy et al 2011).
The main steps in laser cataract surgery are: planning, engagement, visualisation and finally, treatment. To this end, the LenSx system combines the femtosecond laser with an imaging and alignment system (Figure 7). Prior to the procedure high-resolution images are taken to produce accurate biometric measurements of the eye including the thickness of the lens and cornea (He et al 2011; Uy et al 2011). Several papers have reported the use of optical coherence tomography (OCT) for the 3-dimensional mapping of the eye, which is then linked to the femtosecond laser, which performs an anterior capsulotomy followed by fragmentation of the lens and corneal incisions (Palanker et al 2010). The femtosecond3 laser delivers ultrashort pulses of energy at near infrared wavelengths capable of disrupting the targeted ocular tissue.
2
PCO occurs due to residual lens epithelial cells remaining on the anterior capsule, which then go on to colonise the surface of the IOL and the posterior capsule, resulting in decreased visual acuity or a “secondary cataract” 3
Figure 7 The LenSx® demonstrating (printed with permission Alcon Industries Inc)
Patients usually undergo the cataract removal procedure during day surgery. A topical anaesthetic is applied to the eye and the eye is stabilised with a suction “docking” system. This sterile, single-use patient interface allows visualisation of the anterior segment of the eye and locks the laser imaging system with respect to eye movement. Application of the suction patient interface results in a rise in intra-ocular pressure (estimated to be
approximately 50mmHg), whilst maintaining a liquid interface between the eye and the laser, which will focus the laser, minimise the energy required and reduce the cavitation bubble size (He et al 2011). During the capsulotomy, which takes only 10-20 seconds, the femtosecond laser creates a circular incision in the anterior capsule at a pre-programmed diameter. The laser is then used to create incisions within the cataractous crystalline lens (nuclear fragmentation) breaking it up to small fragments. Finally the laser creates corneal incisions to correct astigmatism and allow the surgeon to enter the anterior chamber of the eye. Patients are then transferred to a surgical suite where the fragmented lens can be manipulated, emulsified and aspirated with a phacoemulsification device following which an intraocular lens is inserted. Patients are then kept under observation for approximately one hour before being allowed home with the usual overall time in the Day Surgery being 3-4 hours (personal communication Vision Eye Institute). Click on this link for a demonstration of the cataract removal procedure using the LenSx system (Alcon Laboratories Inc 2011). In Australia there are currently 12 ophthalmic surgeons trained in the use of cataract removal using the femtosecond laser system. Training and accreditation is provided by Alcon LenSx Inc with initial training consisting of an on-line web-based program
demonstrating the equipment, interface technology, laser safety and how to perform the surgery. After familiarisation with all aspects of the technology, the surgeon is required to
undergo 10 supervised procedures under the guidance of a trained company representative (personal communication Vision Eye Institute).
There are no specific infrastructure requirements for the installation of a femtosecond laser apart from standard medical facilities with the provision of an adequate room size to
perform the procedure safely, with appropriate temperature and humidity control and lighting. Ideally the laser room would be situated in close proximity to the surgical suite. 2012 Clinical Need and Burden of Disease
Approximately 15 per cent of all vision loss in Australians is caused by cataract, which was also the third most common cause of blindness, accounting for 12 per cent of all cases (Taylor & Bilgrami 2010).
Australian prevalence data for cataract are based on two large population-based studies conducted in the 1990s: the Melbourne Visual Impairment Project (MVIP) and the Blue Mountains Eye Study (BMES). Combined prevalence data from these two studies estimated rates of vision loss and blindness from cataract that steadily increased with age (Table 6) (Taylor & Bilgrami 2010).
Table 6 Prevalence rates fro vision loss and blindness from cataract(Taylor & Bilgrami 2010)
Age group Vision loss (including blindness) Blindness
40-49 - - 50-59 0.04% - 60-69 0.09% - 70-79 1.42% 0.05% 80-89 6.63% 0.75% 90+ 15.17% 15.51%
When these rates are applied to the population in 2009, it is estimated that approximately 84,960 people may have experienced vision loss from cataract in that year, with 7,700 of these individuals blind due to cataract. Projected rates of vision loss and blindness based on the MVIP and BMES studies and projected population numbers are summarised in Table 7 (Taylor & Bilgrami 2010).
Table 7 Projected number of individuals with vision loss and blindness from cataract (Taylor & Bilgrami 2010)
Age group 2011 2014 2017 2020 VL Blind VL Blind VL Blind VL Blind
40-49 - - - - 50-59 1,225 - 1,291 - 1,332 - 1,354 - 60-69 1,874 - 2,056 - 2,179 - 2,294 - 70-79 18,355 685 20,405 761 23,541 878 26,824 1,001 80-89 48,074 5,448 50,152 5,683 53,138 6,022 57,531 6,520 90+ 22,446 2,240 27,998 2,794 33,447 3,338 38,371 3,829 Total 91,974 8,373 101,902 9,238 113,629 10,238 126,373 11,349
VL = vision loss, including blindness, Blind = blindness
There are a number of Medicare Benefits Schedule item numbers that cover the removal of cataracts:
42698 LENS EXTRACTION, excluding surgery performed for the correction of refractive error except for anisometropia greater than 3 dioptres following the removal of cataract in the first eye;
42701 ARTIFICIAL LENS, insertion of, excluding surgery performed for the correction of refractive error except for anisometropia greater than 3 dioptres following the removal of cataract in the first eye;
42702 LENS EXTRACTION AND INSERTION OF ARTIFICIAL LENS, excluding surgery performed for the correction of refractive error except for anisometropia greater than 3 dioptres following the removal of cataract in the first eye;
42707 ARTIFICIAL LENS, REMOVAL of and REPLACEMENT with a different lens, excluding surgery performed for the correction of refractive error except for anisometropia greater than 3 dioptres following the removal of cataract in the first eye; and
42716 CATARACT, JUVENILE, removal of, including subsequent needlings.
The total number of services provided for these MBS item numbers is summarised in Table 8, indicating the number of cataract procedures performed in the private sector.
Table 8 Number of cataract services performed, July 2010 – June 2011
MBS item number Number of services
42698 224 42701 438 42702 135,815 42707 397 42716 78 Total 136,952
The AIHW hospital morbidity database reported that the total number of procedures performed in Australia’s public hospitals on the anterior segment of the lens for the year 2005-2006 was 179,118. The most common procedure associated with the lens of the eye was “197: Extracapsular crystalline lens extraction by phacoemulsification”, with 165,848 procedures performed, and of these, 155,070 were performed on the same day as admittance.
2012 Diffusion of technology in Australia
An Alcon LenSx® system was installed in the Vision Eye Institute in Sydney in April 2011, which was the fourth such system installed worldwide (Budapest, Hungary; Texas and Utah, USA). Since installation, this facility has performed in excess of 1,000 laser cataract
procedures for private patients. Since this time, two additional units have been installed in private clinics: one in Sydney, one in Melbourne and one will be installed in Hobart early in 2012. Worldwide there are approximately 170 ophthalmic surgeons trained in the cataract removal procedure using LenSx laser and the total number of procedures performed is in the region of 7,500 (personal communication Vision Eye Institute).
2012 Comparators
Cataract surgery is a common procedure with phacoemulsification being the preferred method. During this procedure an incision is made in the eye to enable the removal of the anterior face of the capsule containing the crystalline lens. A probe is introduced into the eye and the cataract is broken up, usually by ultrasound, into small pieces which are then emulsified and removed by aspiration. The entire posterior capsule and the remaining portion of the anterior capsule are left behind forming a capsular bag. The lens is replaced with an in situ permanent intra-ocular lens implant (IOL), which is positioned in the capsular bag and allows the eye to focus again. By leaving the posterior lens capsule intact an
anatomical barrier between the anterior and posterior segments of the eye is formed, reducing the number of potential complications compared to procedures in which the whole lens with intact capsule is removed from the eye (Merlin et al 2011).
2012SAFETY AND EFFECTIVENESS
Nagy et al (2009) reported the preliminary results of anterior capsulotomy and
phacofragmentation performed with a femtoseond laser (LenSx®) in porcine eyes. Following the success of these procedures, a small case series (n=9) was conducted in human patients (mean age 61 years, range 48 to 77 years) (level IV intervention evidence). The first patients in the series underwent only one aspect of the cataract removal procedure, that is, three patients underwent lens fragmentation and three patients underwent anterior capsulotomy only. The final three patients underwent both anterior capsulotomy and lens fragmentation using the LenSx® laser system. After planning and patient preparation, the combined laser capsulotomy and fragmentation procedure was performed in less than one minute.
Following the laser procedure, patients were evaluated with optical coherence tomography (OCT), which revealed a complete cut edge in all scanned meridians. The procedure was completed with standard phacoemulsification. Patients were followed up post-operatively at the standard time points following cataract surgery at one day, one week and one month. Anterior capsulotomy was complete in all patients that underwent this procedure, with no additional incisions required and no radial tears reported. In addition, the size of the removed capsule equalled the measurements taken during procedure planning. Lens removal and IOL implantation was uneventful in all eyes, with no posterior capsule tears reported. At day one follow-up, mild oedema and trace anterior chamber cells were
observed in 7/9 (78%) and 6/9 (67%) patients, respectively, however these symptoms were resolved at 1-week follow-up. At day-1, corrected distance visual acuity was 20/404 or better in 7/9 (78%) eyes. At 1-week follow-up all nine patients had achieved 20/40 visual acuity, which improved in all patients to 20/20 at 1-month follow-up. Mean baseline intraocular pressure5 (IOP) was 13.8 mmHg (range 10-18 mmHg). Mean IOP at day, 1-week and 1-month follow-up was 16.1 (range 12 to 19), 16.0 (15 to 18) and 14.2 (11 to 18) mmHg, respectively (Nagy et al 2009).
An abstract submitted to the Association for Research in Vision and Ophthalmology’s 2010 conference compared the clinical outcomes of patients who underwent conventional phacoemulsification in one eye and femtosecond laser cataract surgery in the other eye (level III-2 intervention evidence). Laser capsulotomy with or without lens fragmentation was performed first on the eye that was the most visually compromised. As a control, the fellow eye was subsequently operated on using standard phacoemulsification surgery. The time between these two procedures being performed was not stated (Edwards et al 2010). Only the results from 60 laser treated eyes and 45 conventionally treated fellow eyes were reported. It is unclear what the clinical outcomes of the remaining 15 control eyes were. At 3-month follow-up logMAR uncorrected visual acuity was 0.30 ± 0.20 and 0.23 ± 0.16 for the
4
A visual acuity of 20/20 is frequently described as meaning that a person can see detail from 20 feet away the same as a person with normal eyesight would see from 20 feet. If a person has a visual acuity of 20/40, they can see detail from 20 feet away the same as a person with normal eyesight would see it from 40 feet.
5
laser and control eyes, respectively. The logMAR6 best corrected visual acuity7 was 0.05 ± 0.10 and 0.03 ± 0.05 for laser and control eyes, respectively. Although the differences between visual acuity in the intervention (laser) eyes and the control eyes were small it is unclear whether these differences were clinically significant or not as a statistical analysis was not reported. IOP was 14 ± 2 mmHg for both groups at baseline and was 13±2mmHg at 3-months. Three and four eyes in the laser and control group, respectively, reported
pressures over 25mmHg at day one post-operatively, however this increase in pressure had reduced by 1-week follow-up. A rise in IOP of >10 mmHg at day-1 was noted in four eyes in each group, which was also resolved by 1-week. At 3-months corneal thickness was 548 ± 38um and 542 ± 57um at baseline and 531 ± 37um and 529 ± 45um for laser and control groups, respectively (Edwards et al 2010).
One of safety issues associated with cataract surgery is the occurrence of subclinical macular oedema and an associated increase in retinal thickness. To assess whether or not the
suction ring used during the positioning of the femtosecond laser had any effect on macular structure, the small study by Ecsedy et al (2011) measured macular thickness using OCT in continuous curvilinear capsulorrhexis (CCC, n=20) and femtosecond laser (FS, n=20) treated eyes (in different patients not fellow eyes). There was no statistical difference in post-operative macular thickness between the two groups8, however differences were noted between the two groups after adjusting for age and pre-operative thickness. The inner macular ring in the CCC group was significantly thicker at 1-week follow-up (mean difference 21.68 µm, 95% CI [11.93, 31.44], p<0.001). This difference was reduced at 1-month follow-up to a mean difference of 17.56 µm (p=0.09). Macular thickness increased significantly compared to baseline (273.3 µm) in the CCC group at 1-week (287.76 µm, p<0.001) and continued to increase at 1-month (298.38 µm, p=0.003). In comparison, macular thickness in the FS group did not increase at 1-week but was significantly increased at 1-month (281.98 µm, p=0.02). This delay in macular thickness may be due to inflammation caused by the manipulation of the intraocular tissues. Although this small study suggests that FS laser removal of cataracts is associated with reduced early macular thickness compared to CCC, a longer follow-up period would be required for any firm conclusions. The visual acuity results of this study are summarised in Table 9 (Ecsedy et al 2011) (level III-2 intervention
evidence).
6
logMAR 0.00 = 20/20, logMAR 0.30 = 20/40, logMAR 0.20 = 20/32 7
Best corrected visual acuity means the best visual acuity score that can be achieved when the best glasses prescription is used.
8
Table 9 Visual acuity results
(Ecsedy et al 2011)
FS group (n=20)
Median corrected distance visual acuity
Pre-op 0.32 ± 0.24 log MAR 1-week 0.16 ± 0.27 log MAR 1-month 0.08 ± 0.19 log MAR
CCC control group (n=20)
Median corrected distance visual acuity
Pre-op 0.39 ± 0.28 log MAR 1-week 0.08 ± 0.16 log MAR 1-month 0.02 ± 0.06 log MAR
Several papers describing technical aspects of FS cataract removal compared to CCC have been published by the same collaborating researchers, with at least two of these authors acknowledging a financial arrangement with Alcon-LenSx Lasers Inc. The results of these studies were not summarised in this brief due to their technical nature, rather than an emphasis on safety and effectiveness (Kranitz et al 2011; Mihaltz et al 2011; Nagy et al 2011). These studies concluded that the removal of cataract by FS was more precise and that the FS procedure resulted in a superior positioning of the IOL.
2012 Cost Impact
The Alcon LenSx costs approximately A$600,000 (personal communication Alcon Laboratories Australia Pty Ltd).
There are several Medicare Benefits Schedule item numbers associated with the removal of cataracts and the insertion of an IOL (42698, 42701, 42702, 42707 and 42716 with
respective fees of: $583.65, $325.50, $746.45, $782.25 and $1,173.40) with each one applicable for either manual or laser cataract surgery. There is no specific MBS item number for femtosecond laser anterior capsulotomy. The cost of a cataract removal procedure, in one eye, using the femtosecond procedure is estimated to be a total of $2,000 to $3,350, which is broken down to $1,150 to $2,500 for the surgery and $850 for the laser
component. Currently the $850 cost for the laser is a private co-payment with no additional cost to the public health system or Medicare.
The 2009 allocated health system expenditure for conditions of the eye was $2.58 billion. It has been estimated that of this total, cataracts accounted for 18 per cent of this
expenditure, and as such is the largest single disease cost care category ahead of refractive error (16%) and glaucoma (8%). Access Economics have projected that the total allocated health systems costs for cataract will increase from $459 million in 2009 to $847 million in 2020 (Taylor & Bilgrami 2010).
2012 Ethical, Cultural or Religious Considerations
Approximately 80 per cent of Aboriginal and Torres Strait Islander adults report having eye problems. Among those aged over 40 years, Aboriginal and Torres Strait Islander people have six times the rate of blindness of non-Indigenous Australians, with the most common cause of blindness being cataract, making up 32 per cent of cases (AIHW 2012).
2012 Other Issues
This technology is likely to only be available in major regional centres in private practice. In Australia, the majority of eye health workers work in city centres (80%), however in 2006, less than 67 per cent of the Australian population with eye disorders live in city centres (AIHW 2009).
The results of the first 1,000 cases of cataract surgery conducted by the Vision Eye Institute in Sydney using the Alcon LenSx® system is to be reported early in 2012 in Ophthalmology. 2012 Summary of Findings
The studies included for assessment in this brief described the results of early, explorative studies on small patient groups. These early studies have indicated that the use of
femtosecond lasers to remove cataract is effective with what appears to be very little
difference in clinical outcomes when compared to conventional anterior capsulotomy (visual acuity, macular thickness and adverse events). However, there was little statistical analysis of the results, possibly due to the small sample size. Therefore firm conclusions as to the effectiveness of the FS procedure compared to CCC are difficult to make. A large Australian study (1,000 patients) is due to be published in January 2012, however it is a case series and therefore not comparative and capable of informing safety aspects of the FS procedure. Although it would be prudent to await the publication of any randomised controlled trials evaluating the use of FS compared to CCC, it would appear that this technology is rapidly diffusing throughout the private health sector in Australia.
2012 HealthPACT Assessment:
There appears to be no significant clinical advantage over the use of the femtosecond lasers to remove cataracts in comparison to conventional phacoemulsification, especially when consideration is given to the high cost of the new technology. It would appear that the femtosecond laser technology for the removal of cataracts is rapidly diffusing in the private sector throughout Australia, however the technology is unlikely to impact on the public system in terms of patient flow and reduced waiting times for cataract surgery. There is a paucity of comparative evidence, in the form of randomised controlled trials, with the reported evidence to date conducted on relatively small patient groups. Therefore
HealthPACT have recommended that this technology be monitored for further information in 24-months.
2012 Number of Studies included
Total number of studies 3
Total number of level III-2 intervention evidence 2 Total number of level IV intervention evidence 1
