Attitudes and understanding of premium intraocular lenses in cataract surgery: a public health sector patient survey

OBJECTIVES

To investigate patient understanding of, and attitudes to, premium (toric, extended depth of focus/multifocal) intraocular lenses (premIOLs) in public health sector patients undergoing cataract surgery (CS) in the UK.

METHODS

A 12 question survey with Likert scale questions was designed, to assess patient attitudes to post-operative spectacle dependence, refractive target and desirability of spectacle independence whilst considering possible complications of dysphotopsias and need for premIOL exchange/adjustment.

RESULTS

360 surveys were collected. CS had not been performed in 66.5%. Separate spectacles were worn for reading and distance in 28.8%, 19.2% had varifocals, 11.2% bifocals, 22.9% reading glasses only and 1.6% computer glasses only. Contact lenses were not worn in 95.7%. Only 41.6% were drivers. Most patients (85.8%) did not mind wearing glasses after CS, with 78.9% preferring reading glasses, compared with 29.7% preferring distance glasses. Most patients (75.3%) were not familiar with premIOLs, with 58.9% not willing to consider them in the context of a 2% risk of debilitating dysphotopsia and 54.2% rejecting a 5% risk of second surgery.

CONCLUSIONS

There is a lack of awareness of premIOLs in public health sector (NHS) patients in the UK, suggesting limitations in the "fully informed" consent process for CS. Most NHS CS patients are currently willing to wear spectacles after CS, especially reading glasses. There is reluctance in such patients to consider premIOLs on a background of small risks of debilitating dysphotopsias and increased risks of a second operation.

Time and Motion Studies to assess surgical productivity in cataract theatre lists within the National Health Service: Immediate Sequential Bilateral Cataract Surgery versus Delayed Sequential Bilateral Cataract Surgery

BACKGROUND

To compare productivity of National Health Service cataract lists performing unilateral cataract (UC) surgery vs Immediate Sequential Bilateral Cataract Surgery (ISBCS).

METHODS

Five 4-hour lists with ISBCS cases and five with UC were observed using time and motion studies (TMS). Individual tasks and timings of each staff member in theatre was recorded by two observers. All operations were performed by consultant surgeons under local anaesthesia (LA).

RESULTS

Median number of eyes operated per 4-hour list was 8 (range 6-8) in the ISBCS group and 5 (5-7) in the UC group (p = 0.028). Mean total theatre time (defined as time between the entry of the first patient and the exit of the last patient from theatre) was 177.12 (SD 73.62) minutes in the ISBCS group and 139.16 (SD 47.73) minutes in the UC group (p = 0.36). Mean time to complete two consecutive unilateral cataract surgery operations was 48.71 minutes compared to 42.23 minutes for a single ISBCS case (13.30% time saved). Based on our collected TMS data, a possible 5 consecutive ISBCS cases and 1 UC (total 11 cataract surgeries) could be performed during a four-hour theatre session, with a theatre utilisation quotient of 97.20%, contrasting to nine consecutive UC, with a theatre utilisation quotient of 90.40%.

DISCUSSION

Performing consecutive ISBCS cases under LA on routine cataract surgery lists can increase surgical efficiency. TMS are a useful way to investigate surgical productivity and test theoretical models for efficiency improvements.

Heavy silicone oil tamponade: a multicentre experience

OBJECTIVE

To report multicentred use of the heavy silicone oil Densiron 68 for anatomical reattachment following rhegmatogenous retinal detachment (RRD) repair and its associated complications.

METHODS AND ANALYSIS

Patients from seven vitreoretinal units within the UK that underwent RRD repair with Densiron 68 between January 2015 and December 2019 were identified. Primary outcome measures were primary and final reattachment rate, retained Densiron and failure rate. Secondary outcome measures were duration of tamponade, final visual acuity (VA) and complications of heavy silicone oil.

RESULTS

134 eyes of 134 patients were involved in the study. Primary surgical success was achieved in 48.5%, while a final reattachment rate of 73.4% was observed. The mean duration of Densiron 68 tamponade was 139.5 days. Mean final VA was 1.01 (range 0-2.9). 8 eyes (6.0%) required long-term topical steroids for anterior uveitis, whereas none of the eyes required long-term pressure-lowering treatment. Emulsification rate was 10.7% (6 eyes).

CONCLUSION

This is the largest real-world study on Densiron 68 in the UK. Densiron 68 facilitates tamponade of inferior retinal pathology and may be considered as an option for tamponade of inferior retinal pathologies.

Acceptability of immediate sequential bilateral cataract surgery (ISBCS) in a public health care setting before and after COVID-19: a prospective patient questionnaire survey

Objective

To ascertain patient acceptance of immediate sequential bilateral cataract surgery (ISBCS) in the National Health Service (NHS).

Methods

A survey was devised using a 5-point Likert scale for questions related to ISBCS, which patients undertook during their cataract outpatient appointment pre-COVID-19 lockdown and by telephone during the lockdown.

Results

Questionnaires were completed for 267 patients. Most respondents were aged over 71 (51%) and were female individuals (60%). Forty-five per cent agreed/strongly agreed with opting for ISBCS. A positive correlation was identified between opting for ISBCS and convenience to the patient (r=0.76, p<0.01) and family/carer/partner (r=0.71, p<0.01) and wanting to limit numbers of hospital visits (r=0.57, p<0.01). Fifty per cent agreed/strongly agreed that they were worried about the risk of simultaneous bilateral ocular complications, with this correlating with being less likely to opt for ISBCS (r=-0.49, p<0.01) and being scared of ISBCS (r=0.67, p<0.01). During COVID-19 lockdown, patients were less likely to want to minimise the time taken off work (p<0.05) and less intolerant of a prolonged hospital visit (p<0.05). Only 23% of respondents agreed/strongly agreed that they had familiarity with ISBCS.

Conclusions

ISBCS was acceptable to 45% of our sampled population, suggesting limited routine implementation in the NHS is possible. Convenience and reduction in hospital visits appeared to contribute to this acceptance. Half of the patients expressed concern regarding bilateral complications and such concerns need addressing. Some attitudes did appear to change during the COVID-19 lockdown period. The familiarity of the concept of ISBCS is low suggesting the need for patient education.

Cataract surgery and dry eye disease: A review

AIM

To review published literature concerning cataract surgery and dry eye disease (DED).

METHODS

A search was undertaken using the following: PubMed (all years), Web of Science (all years), Ovid MEDLINE(R) (1946 to 12 December 2019), Ovid MEDLINE(R) Daily Update 10 December 2019, MEDLINE and MEDLINE non-indexed items, Embase (1974-2019, week 49), Ovid MEDLINE (R) and Epub Ahead of Print, In-Process and Other Non-Indexed Citations and Daily (1946 to 12 December 2019), CENTRAL (including Cochrane Eyes and Vision Trials Register; Cochrane Library: Issue 12 of 12 December 2019), metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and WHO International Clinical Trials Registry Platform (www.who.int/ictrp/search/en). Search terms included 'cataract surgery', 'phacoemulsification' and 'cataract extraction', combined with 'dry eyes' and 'ocular surface'. Relevant in-article references not returned in our searches were also considered.

RESULTS

Publications identified included systematic reviews, meta-analysis, randomized controlled trials, cohort studies, case series and laboratory-based studies. Published data highlighting the burden of DED both prior and following cataract surgery were reviewed as well as studies highlighting the effects of cataract surgery on the ocular surface, intra-operative measures to reduce deleterious effects on the ocular surface and current evidence on the management options of post-operative DED.

CONCLUSIONS

DED is common and can be exacerbated by cataract surgery. Ophthalmologists need to assess for pre-existing DED and instigate treatment before surgery; be aware of reduced accuracy of measurements for surgical planning in the presence of DED; limit intra-operative surgical factors damaging to the ocular surface; and consider management to reduce DED post-operatively.

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.

Economic modelling of immediately sequential bilateral cataract surgery (ISBCS) in the National Health Service based on possible improvements in surgical efficiency

Objective

To test a hypothesis that operating room (OR) productivity in the National Health Service (NHS) can be improved with the introduction of immediately sequential bilateral cataract surgery (ISBCS).

Methods and analysis

Previously published time and motion data of 140 unilateral cataract surgeries conducted at five different NHS locations were reanalysed to construct a hypothetical model where only ISBCS (±one unilateral case) were conducted while maintaining time durations of all key tasks previously studied. Possible time efficiency savings were calculated for the ISBCS model and percentage increases in numbers of eyes operated per 4-hour theatre session calculated. Gains in efficiency were correlated with factors from the baseline data to predict which settings could improve efficiency most by undertaking ISBCS.

Results

Based on remodelling our time and motion study (TMS) data as hypothetical ISBCS cases, we could expect a mean 16% reduction (range 9.8%–17.8%) in the time taken for two cataract operations, translating into a mean 54% improvement (range 38%–67%) in number of cases currently performed per list and an 18% improvement (range 9%–28%) even if the number of unilateral cases per list had been fully maximised. An average number of four ISBCS cases per list (range 3–6) were required to achieve sufficient time savings to allow an extra unilateral surgery to be conducted.

Conclusion

The introduction of routine ISBCS has the potential to improve the productivity of cataract surgery within the NHS, with efficiencies being possible in both high-volume and low-volume surgical models.

Children with cystic fibrosis demonstrate no respiratory immunological, infective or physiological, consequences of vitamin D deficiency

BACKGROUND

Vitamin D has health benefits in many respiratory diseases but the evidence in CF is unclear. Induction of the antimicrobial peptides cathelicidin (LL37) and human-beta-defensin-2 (HBD-2) may be the mechanism of any benefit. We hypothesised that antimicrobial peptide levels would be decreased, and airway infection and inflammation greater, in CF children with vitamin D deficiency. The objective of the study was to explore relationships between vitamin D, LL37 and HBD-2, and airway infection, inflammation and physiology in children with CF.

METHODS

Bronchoalveolar lavage (BALF) and blood were obtained from children undergoing fibreoptic bronchoscopy. Serum vitamin D, BALF HBD-2 and LL37, cultured bacteria and inflammatory markers were measured. Clinical parameters were recorded.

RESULTS

113 patients with CF, 23 with non-CF chronic suppurative lung disease (CSLD) and 6 healthy controls were included. We found no relationship between serum vitamin D and BALF HBD-2 or LL-37. There were no differences in infective or inflammatory markers between vitamin D sufficient and deficient groups. Vitamin D deficient patients (<50 nmol/L) did not have a worse FEV₁ (CF: 66 (58-71)% vs. 71.5 (61-76)%, ns; non-CF CSLD: 69 (36-88)% vs. 70 (62-95)%, ns).

CONCLUSIONS

In the first bronchoscopic study exploring this question, we demonstrate that vitamin D deficiency is not associated with immunological, infective or clinical markers of disease severity in patients with CF or CSLD.

Clarifications on Oil/Heavy Oil Recovery Under Ultrasonic Radiation Through Core and 2D Visualization Experiments

Abstract

Our previous research on the effects of ultrasonic waves on oil recovery conducted at the University of Alberta had shown that capillarity and interfacial tension (IFT) might be responsible for the observed improvements in incremental oil recovery. Although the results seem encouraging, questions about the mechanism and effective parameters causing additional recovery still remain.

To analyze the influence of parameters other than IFT and capillary forces, we conducted capillary imbibition experiments on cylindrical Berea sandstone core samples under ultrasonic radiation, and the results are presented in this paper. Through this experimental scheme, we focused on:the effect of initial water saturation for rocks with different wettability;oil viscosity; andmatrix wettability. The cores were placed into imbibition cells where they were contacted with an aqueous phase. Every experiment was conducted with and without ultrasonic radiation for comparison. Different intensities of ultrasonic waves were tested as well.

To investigate the acoustic interaction between rock and fluid, we performed certain visualization experiments. We used 2D glass bead models to clarify the effects of ultrasonic waves on the oil displacement process for different oil viscosities and matrix wettability through comparative analysis.

The qualitative and quantitative observations and analyses presented are expected to provide additional understanding regarding investigations in the use of in situ recovery of oil/heavy oil, as well as surface extraction.

Introduction

Acoustic energy was considered as one of the unconventional EOR methods to replace or to be applied with conventional ones. Studies have been conducted to understand the effects of acoustic energy on oil recovery over the last four decades. Duhon and Campbell(1) performed waterflood tests of cores with ultrasonic energy and showed that the ultrasonic energy improved the oil recovery and displacement efficiency in the cores.

Beresnev and Johnson(2) performed a critical analysis of the work done in this area up to the early 1990s and provided a comprehensive review of the seismic and ultrasonic stimulation studies. They concluded that the elastic wave and seismic excitations of porous media affect permeability and production rates in most cases

Kuznetsov et al.(3) reviewed seismic techniques for enhanced oil recovery and observed an increase in oil/water relative permeabilities and also oil recovery after elastic vibration. They concluded that this increase is due to fines removal by vibration.

Roberts et al.(4) applied mechanical stresses to rock samples which were placed inside a core holder and observed changes in permeability and an increase in wettability in the non-wetting phase.

There also exists field-scale applications of sound waves of different characteristics. Spanos et al.(5) observed improvements in waterflooding and injectivity when pressure pulses were applied by a hydraulically-operated tool. Westermark et al.(6) applied a complex system of vibration tools in the field and observed an improvement in permeability at certain intensities and up to a 20% increase in the oil production rate. Zhu et al.(7) documented the results of the application of a special downhole vibration tool in several oil fields in China, pointing out that sand content, water content, viscosity and density of oil decreased after treatment.