A review of posterior chamber phakic intraocular lenses.

PURPOSE OF REVIEW: Posterior chamber phakic intraocular lenses (pIOLs) are increasing in popularity as a viable alternative to laser refractive surgery. The purpose of this review is to evaluate the recent updates to pIOLs and to assess the advancements and safety of the procedure. RECENT FINDINGS: Accurate lens sizing is the key determinant to suitable vault prediction, advancements to sizing formulae including the use of very high frequency (VHF) digital ultrasound and the application of artificial intelligence and machine learning has led to improved vault prediction and safety. The introduction of the central aquaport has been shown to reduce the formation of cataract and is now adopted in most myopic pIOLs. Recently published studies have demonstrated that pIOLs have an excellent safety profile with no increased risk of retinal detachment or endothelial cell loss. Advancements have led to the introduction of extended depth of focus pIOLs for the correction of presbyopia, further research is required to evaluate the efficacy of new lens designs. SUMMARY: pIOL surgery is experiencing traction with improved lens design and increased lenses choices such as larger optical zone and presbyopic options. Accuracy of implantable collamer lens sizing is paramount to the safety and clinical outcomes, greater predictability is likely to encourage more posterior chamber pIOL users due to fewer sizing related complications.

Contact Lens Use Advice-Risks and Outcomes: Are Patients Drowning in Information but Starved for Knowledge?

Objectives: Microbial keratitis can cause significant visual morbidity and is a common reason for presentation to eye casualty clinics. Contact lens wear and poor contact lens hygiene significantly increase the risk of corneal infection. This study aimed to determine the level of contact lens hygiene awareness amongst contact lens wearers attending our service and determining whether contact lens type and hygiene attitude are related to severity of disease. Materials and Methods: This prospective questionnaire-based study included 50 consecutive patients attending the eye casualty clinic of a tertiary referral center. Visual acuity was assessed at presentation and 2 weeks after diagnosis. Patients were divided into subgroups according to contact lens type (monthly, bi-weekly, daily, and extended day and night wear) and risk group (low, medium, and high) depending on their contact lens hygiene practices. Results: Thirty-four women and 16 men were included in this study. Twenty-four patients used monthly disposable contact lenses, 16 used daily disposable contact lenses, 6 were using bi-weekly replacement lenses, and 4 patients were using extended wear (day and night) contact lenses. Twenty-five patients were diagnosed with corneal ulcer, 23 of which had some degree of poor contact lens hygiene. Best corrected visual acuity (BCVA) significantly improved after treatment. Mean BCVA was 0.24 LogMAR before treatment and 0.09 LogMAR after treatment (p<0.05). Conclusion: Our study highlights the need to improve contact lens hygiene awareness and influence hygiene practices. Patients with the poorest contact lens hygiene had slower visual recovery and a higher prevalence of corneal ulcer. Contact lens hygiene advice needs to be clear and reinforced over time.

Personal hygiene risk factors for contact lens-related microbial keratitis.

OBJECTIVE: Microbial keratitis is a sight-threatening complication of contact lens wear, which affects thousands of patients and causes a significant burden on healthcare services. This study aims to identify compliance with contact lens care recommendations and identify personal hygiene risk factors in patients who develop contact lens-related microbial keratitis. METHODS AND ANALYSIS: A case-control study was conducted at the University Hospital Southampton Eye Casualty from October to December 2015. Two participant groups were recruited: cases were contact lens wearers presenting with microbial keratitis and controls were contact lens wearers without infection. Participants underwent face-to-face interviews to identify lens wear practices, including lens type, hours of wear, personal hygiene and sleeping and showering in lenses. Univariate and multivariate regression models were used to compare groups. RESULTS: 37 cases and 41 controls were identified. Showering in contact lenses was identified as the greatest risk factor (OR, 3.1; 95% CI, 1.2 to 8.5; p=0.03), with showering daily in lenses compared with never, increasing the risk of microbial keratitis by over seven times (OR, 7.1; 95% CI, 2.1 to 24.6; p=0.002). Other risks included sleeping in lenses (OR, 3.1; 95% CI, 1.1 to 8.6; p=0.026), and being aged 25-39 (OR, 6.38; 95% CI, 1.56 to 26.10; p=0.010) and 40-54 (OR, 4.00; 95% CI 0.96 to 16.61; p=0.056). CONCLUSION: The greatest personal hygiene risk factor for contact lens-related microbial keratitis was showering while wearing lenses, with an OR of 3.1, which increased to 7.1 if patients showered daily in lenses. The OR for sleeping in lenses was 3.1, and the most at-risk age group was 25-54.

Combined photorefractive keratectomy and cross-linking. Pushing the limits.

Correction of refractive error through laser-assisted means has soared in popularity in recent years, allowing it to become an increasingly routine surgical procedure. Technique refinement and adjustments resulted in laser-assisted refractive surgery to be combined with treatments such as collagen cross linking (CXL). This has broadened safety parameters and widened the treatment boundaries. Laser correction combined with CXL has been advocated in the treatment of high refractive errors as a safe option for full refractive correction while increasing corneal biomechanical stability. We present a complicated case where a young female patient with a preoperative best-corrected visual acuity (BCVA) of 20/20 in each eye was fully corrected by excimer laser followed by CXL. Factors potentially leading to inflammation, such as ocular surface disease, in addition to laser treatment and CXL, resulted in persistent epithelial defect followed by corneal melt and subsequent thinning. After the treatment, the patient relies on rigid gas-permeable contact lenses, achieving a BCVA of 20/25 and 20/23 in the right eye and left eye, respectively.

Ratios for double silicone oil Endotamponade - in vitro observations may assist with ratio selection.

BACKGROUND: Silicone oil tamponade is more frequently reserved for cases of complex retinal detachment. We describe the effects of different variations in oil ratios with the relatively unknown technique of double oil tamponade. METHODS: Retrospective case note review of nine patients with complex rhegmatogenous retinal detachment (RD). All cases had both superior and inferior breaks, mostly with associated proliferative vitreoretinopathy (PVR). All cases were treated with pars plana vitrectomy (PPV) and a double silicone oil endotamponade (DSOE) of both heavy silicone oil and conventional 'light' silicone oil. Ratios were varied to suit different RD configurations. In vitro observations were studied to help direct these decisions. RESULTS: Anatomical success was achieved in all cases. Common complications were the same as those seen in single oil tamponade (elevated intraocular pressure, cystoid macular oedema (CMO), cataract and posterior capsule opacification. No single case of recurrent RD was seen whilst mixed oil remained in situ. CONCLUSIONS: Double silicone oil endotamponade is a safe and effective treatment for complex retinal detachments with superior and inferior breaks. Differences in oil ratios can be tailored to best fit the distribution of retinal pathology. In vitro observations may help to inform these choices.

A review of keratoconus: Diagnosis, pathophysiology, and genetics.

We discuss new approaches to the early detection of keratoconus and recent investigations regarding the nature of its pathophysiology. We review the current evidence for its complex genetics and evaluate the presently identified genes/loci and potential candidate gene/loci. In addition, we highlight current research methodologies that may be used to further elucidate the pathogenesis of keratoconus.

Non-arteritic Anterior Ischaemic Optic Neuropathy after Uneventful Cataract Extraction.

We present the case of a 74-year-old Caucasian female who suffered sudden visual loss after routine phacoemulsification cataract surgery. The patient was subsequently diagnosed with non-arteritic anterior ischaemic optic neuropathy. The case is described in detail, and a concise review of the literature is presented together with the authors' view on the subject outlined. This is a very rare complication after cataract surgery even in high-risk patients with associated systemic co-morbidities. We suspect that the previous history of obesity, coronary artery disease, and arteriosclerosis contributed to the development of this serious ocular complication. We suggest appropriate measures to reduce the risk of its occurrence.

Herpes simplex virus keratitis: an update of the pathogenesis and current treatment with oral and topical antiviral agents.

Ophthalmic herpes simplex viral keratitis is responsible for a range of ocular manifestations from superficial epithelial disease to stromal keratitis and endotheliitis. The Herpetic Eye Disease Study has guided the management of herpetic eye disease for almost twenty years, but newer medications such as valacyclovir are now available and are considered to have better bioavailability than acyclovir. In this review, we examine the existing evidence on the pathogenesis of different ophthalmic herpes simplex viral keratitis disease modalities and the role of oral and topically administered antiviral drugs in the treatment of herpes simplex viral keratitis.

Neuropathic Pain in Multiple Sclerosis Improved With Oral Famciclovir: A Case Report.

Multiple sclerosis can be a debilitating disease that is often associated with neuropathic pain and discomfort in the trigeminal region. This can pose a therapeutic challenge as the benefits of the treatment options have to be outweighed against significant side effects. The authors present the case of a 67-year-old man, whose control of trigeminal neuralgia with botulinum toxin A injections was lost after an episode of herpes labialis and herpes zoster infection. The pain management of the patient during the episodes of herpes simplex and varicella zoster infections was greatly improved with famciclovir treatment, and subsequently control of trigeminal neuralgia was regained with botulinum toxin A injections. This case serves to highlight the potential association of multiple sclerosis with herpetic infections as well as the treatment challenges, especially management of pain, which they can possess.