RES: lubricate or bandage?
Randomized controlled study of ocular lubrication versus bandage contact lens in the primary treatment of recurrent corneal erosion syndrome
Adad MA, Anandan M, Tah V et al. Cornea. 2013; 32:1311-1314
This randomised controlled trial of 29 patients aimed to investigate the efficacy of bandage contact lenses (BCLs; n=14) compared with ocular lubricants (OLs; n=15) in the initial management of recurrent corneal erosion syndrome (RCES). The patients received treatment for three months with either extended wear monthly replacement BCLs (Air Optix Night and Day lenses; CIBA Vision) or OLs qid with ointment overnight (Celluvisc; Allergan and Lacrilube; Allergan). Monthly assessment was carried out for four months with the main outcome measure of complete symptom resolution with no noticeable corneal surface abnormality. Patients with complete resolution were followed up for another three months to check for recurrence. After three months, complete resolution was achieved in 71% of BCL patients and 73% of OL patients; partial resolution in 7% of BCL patients and 13% of OL patients. 21% of BCL and 13% of OL patients failed to respond to treatment. Earlier resolution was achieved in BCL patients with a mean time of five weeks compared with nine weeks for OLs (P=0.02). There were no cases of adverse side effects. The study concluded that, when compared to OLs, BCLs do not increase the likelihood of complete resolution in the initial management of RCES, but that it seems to be a safe form of treatment that may offer some patients earlier relief of symptoms.
This paper demonstrates that BCLs and OLs are essentially equally effective in the management of RES which will surprise those who champion BCLs. Each treatment modality has its pros and cons. Lubricants require less follow up visits and thus expense for the patient. Contact lenses are simpler for those who can’t apply lubricants. The study also reminds us that RES can take a long time to settle and that a significant number of patients will need more than simple measures. For this reason I use tetracycline ointment as the nocte lubricant and give patients prescribed BCLs oral Doxycycline to improve the likelihood of success.
Comparative analysis of refractive and topographic changes in early and advanced keratoconic eyes undergoing corneal collagen crosslinking
Arora R, Jain, P, Goyal JL and Gupta, D. Cornea. 2013; 32:1359-1364
This prospective, nonrandomized comparative clinical intervention study compared the refractive and topographic changes of 30 eyes with early and advanced keratoconus one year after undergoing corneal collagen crosslinking (CXL). Group A had mean central K < 53D; Group B had mean central K > 53D. Uncorrected vision (UCVA), best-corrected visual acuity (BCVA), refraction, topography, pachymetry and endothelial cell counts were evaluated at baseline and at 1, 3, 6 and 12 months of follow up. The mean baseline logMAR UCVA and logMAR BCVA in group A was 1.007+ 0.30 and 0.566 + 0.21 respectively, improving to 0.727 + 0.29 (P=0.001) and 0.306 + 0.15 (P= 0.001) at 12 months post CXL. Mean baseline logMAR UCVA and BCVA in group B was 1.040 + 0.24 and 0.641 + 0.25 respectively, improving to 0.953 + 0.26 (P= 0.054) and 0.633 + 0.27 (P=0.891) at 12 months post CXL. The improvement in group A was statistically significant compared to group B. In group A the mean baseline flattest, steepest, central and apical keratometry were 48.7 + 2.5D, 54.9 + 3.3D, 49.5 + 1.4D and 57.3 + 2.3D respectively, changing to 47.8 + 2.4D, 54.1 + 3.0D, 48.8 + 1.8D and 56.2 + 2.7D at 12 months post CXL. The change was only statistically significant for mean flat and apical K (P<0.05). In group B none of the indices showed any statistically significant change at 12 months (P>0.05). The paper concludes that CXL is more effective in improving refractive and topical parameters when it is performed early in the course of the disease.
The main goal and outcome of crosslinking keratoconics is prevention of progression. Some corneas also flatten A LITTLE. This study demonstrates that flattening is more likely in less severe disease, reinforcing that patients should be referred for treatment as early as possible. Cross linking should still only be used in progressive disease.
CRIMP the cornea. OK works
Corneal Reshaping Influences Myopic Prescription Study (CRIMPS): An analysis of the effect of orthokeratology on childhood myopic refractive stability
Downie, LE and Lowe, R. Eye & Contact Lens. 2013; 39:303-310
This retrospective study compared the right eyes of children undergoing orthokeratology (OK) (n=26) and age- and refraction-matched spectacle wearing control children (n=30) over a period of up to 8 years. Changes to manifest refractive prescriptions were compared between the groups at two-yearly intervals for up to 8 years. At baseline children were under 16 years of age and showed manifest spherical refractive error of more than -0.50 D. Results demonstrated significantly more stable myopia in OK eyes compared to control eyes (P<0.05) over all of the two-year treatment intervals. 64% of OK eyes demonstrated an apparent total arrest of manifest myopic refractive change. Baseline corneal topography showing symmetry in the vertical meridian was associated with a greater degree of refractive stability in OK eyes. This paper concludes that the study provides evidence that OK can reduce the rate of progression of childhood myopia and offers early evidence into predictability of the extent of refractive stability in individual eyes undergoing OK.My comment:
More support for OK in young myopes. It is very exciting that we are finally able to influence the progression of axial myopia. At the recent European Society of Cataract and Refractive Surgeons there was broad consensus that children with myopia should also be presecribed low dose atropine and play outdoors for 2 hours a day. Exactly how all these treatments work is still unclear. To date, 68 genes, coding everything from eye development to retinal neurotransmission and scleral remodelling, have been associated with myopia.
Oasys as a bandage lens
Application of senofilcom A contact lenses for therapeutic bandage lens indications
Shafran T, Gleason W, Lorenz KO, and Szczotka-Flynn LB. Eye & Contact Lens. 2013; 39:315-323
This study is a retrospective consecutive chart review into the therapeutic or bandage lens applications of senofilcon A contact lenses (Acuvue Oasys with hydraclear; Johnson & Johnson Vision Care) for 43 fully consented consecutive patients across three different clinical centres in the United States (Georgia, Florida and Ohio). Included therapeutic indications for contact lens treatment were corneal protection from exposure or repeated irritation, corneal pain relief and barrier protection. Outcome assessments included pain relief, improvement in corneal signs, additional complications and overall treatment success. All fitted lenses were base curve 8.4mm and diameter 14.0mm.
26/43 patients were fitted for pain relief. Of these, 81% were judged to be fully effective, 8% partially effective and 11% ineffective. In 25/43 cases the treatment goal was improvement in corneal integrity. Treatment was judged to be fully effective in 64% of these cases, partially effective in 24% and no change noted in 12% of the cases. Twelve refractive surgery patients (having undergone laser-assisted in situ keratomileusis, epithelial laser-assisted in situ keratomileusis, laser-assisted subepithelial keratectomy, or photorefractive keratectomy) wore the lenses for 4-6 days postoperatively for comfort and protection. Overall treatment was fully successful in 68% of cases, partially successful in 18% of cases and neutral or unsuccessful in 14% of cases. There were no adverse events reported in any of the cases.
This paper concludes that senofilcon A contact lenses are successful in the majority of cases when used for protecting against corneal exposure and recurrent damage, pain management, barrier protection and post-surgical management.
Bandage lenses can be very useful in managing painful and irregular corneas. Most folk seem to use Oasys or Proclear lenses as they are cheap and drape well. They are not always the best option. Consider PureVision (more rigid), Night and Day (in dry eyes) and UltraVision (larger diameter) as well.
Laser vs manual cataract surgery
Effectiveness and safety of femtosecond laser-assisted lens fragmentation and anterior capsulotomy versus the manual technique in cataract surgery
Reddy KP, Kandulla J and Auffarth GU. J Cataract Refract Surg. 2013; 39: 1297-1306
This study compares the effectiveness and safety of femtosecond laser-assisted lens fragmentation and anterior capsulotomy (n= 56) versus manual capsulorhexis and standard phacoemulsification (n= 63). Measured outcomes were effective phacoemulsification time (EPT), surgeon-assessed ease of phacoemulsification, mean phaco energy, mean phaco time, balanced salt solution volume, capsulotomy precision, and adverse event rates. The study found that the mean EPT was significantly lower in the laser group (5.2 + 5.7 seconds) compared to the manual group (7.7 + 6.0 seconds) (P=0.025). The mean phaco energy was significantly lower in the laser group (13.8% + 10.3%) compared to the manual group (20.3% + 8.1%) (P<0.001). The ease of phacoemulsification, mean phaco time and balanced salt solution volume was not significantly different between the groups. Intended diameter, circularity and centration of the laser-assisted capsulotomies were significantly more precise compared to the manual capsulorhexis (P<0.01). There were no adverse events at day one follow up for either group, giving them equivalent safety profiles.The paper concludes that femtosecond laser-assisted lens fragmentation and anterior capsulotomy is effective and safe in cataract surgery, resulting in reduced EPT and mean phaco energy for lens fragmentation and precise and reproducible capsulotomies.My comment:
FLACS (Femtosecond Laser Assisted Cataract Surgery) is one of the most contentious topics in ophthalmology at present. It is clear that FLACS is a good marketing tool; patients and referring optometrists are attracted to the idea of laser surgery. What is less clear is whether it offers ANY clinical advantage for the patient. Sure, the capsulorhexis is perfect but all capsulotomies change postoperatively. The wounds are perfect, but soon distorted by intruments. Yes, phaco times seem shorter, but as one critic at ESCRS said recently on the podium “my non-FLACS phaco times are still less than your FLACS phaco times; I saw you stuffing the port of your phaco to reduce energy use and fudge your results, and anyway who cares about two seconds less phacoemulsification – it means nothing!” It will take some time for the truth to emerge, and then, even if there is an advantage, will it be worth the cost? Take everything you hear about FLACS with a grain of salt; critics usually haven’t got access to a laser and those promoting the technology need to pay for theirs. The first casualty of war is truth…