[The effect of keratoconus-associated refractive errors on the results of tomographic methods of studying the posterior structures of the eye]. / Vliyanie opticheskikh narushenii pri keratokonuse na rezul'taty tomograficheskikh metodov issledovaniya struktur zadnego segmenta glaza.

PURPOSE: The study assesses the potential influence of refractive errors in keratoconus (KC) on the results of tomographic methods of studying the structures of the posterior eye segment. MATERIAL AND METHODS: The study included 30 patients with bilateral stabilized KC of stages I-IV in classification by M. Amsler. Spherical and cylindrical components of refractions were determined using automatic refractometry, keratometry measurements - based on scanning keratotopography with Scheimpflug analyzer. Aberrometry was performed to evaluate corneal wave front according to the following parameters: root mean square for lower order aberrations (RMS LOA), root mean square for higher order aberrations (RMS HOA), vertical trefoil, vertical coma, horizontal coma and spherical aberrations. Optical coherence tomography (OCT) and laser confocal scanning ophthalmoscopy (HRT 3) data was used in morphometric analysis of the optic nerve head and peripapillary retina. The following morphometric parameters were analyzed: optic nerve head (ONH) area, optic disc cup area, optic disc cup volume, ratio of optic disc cup area to ONH area, neuroretinal rim area, neuroretinal rim volume, peripapillary retinal nerve fiber layer (RNFL) thickness. All studies were performed first without correction, and 30 minutes after installing customized scleral hard contact lenses (SHCL). RESULTS: Compensation of the refractive errors characteristic for KC was achieved as expected with contact correction. OCT revealed a general trend for reduction in the area and volume of the optic disc cupping, ratio of area to volume of the optic disc cupping, as well as an increase in other parameters. As such, with correction the values for area and volume of the neuroretinal rim according to OCT were 2.2 and 13%, HRT 3 - 18 and 51.6%; comparable increase in mean RNFL thickness - 2.8 and 28.5%, respectively (p<0.001). According to HRT 3 data, the area and volume of optic disc cupping statistically significantly decreased (by 21 and 28%, respectively), while OCT showed statistically significant decrease only in cupping area (by 5.7%). The ratio of cupping to ONH area decreased by 6.6 and 23% relative to the initial data obtained with OCT and HRT 3, respectively. Significant decrease in ONH area amid SHCL correction was observed only with HRT 3. The revealed changes in morphometric parameters were analyzed using the fundamental principles of physiological optics. Changes in interference pattern and, consequently, morphometric parameters of structures of the eye fundus in KC are of multifactorial nature, and are mostly associated with refractive and wave artefacts occurring when the rays pass through the irregular corneal surface and cannot be optically compensated by the device. The use of SHCL as means for making the optic system relatively regular can significantly decrease the artefacts in morphometric measurements. CONCLUSION: The results obtained in this study demonstrate the practicality of tomographic examination in KC with contact correction. The optimal choice is custom-fit SHCL, which along with proper correction of refractive errors also ensures stable position of the lens on the cornea. In standard examination specialists should take into account the «false¼ decrease in parameters of the peripapillary retinal nerve fiber layer and increase in ONH cupping.

Process evaluation of a National Primary Eye Care Programme in Rwanda.

BACKGROUND: Visual impairment is a global public health problem, with an estimated 285 million affected globally, of which 43% are due to refractive error. A lack of specialist eye care in low and middle-income countries indicates a new model of care would support a task-shifting model and address this urgent need. We describe the features and results of the process evaluation of a national primary eye care (PEC) programme in Rwanda. METHODS: We used the Medical Research Council process evaluation framework to examine the implementation of the PEC programme, and to determine enablers and challenges to implementation. The process evaluation uses a mixed methods approach, drawing on results from several sources including a survey of 574 attendees at 50 PEC clinics, structured clinical observations of 30 PEC nurses, in-depth interviews with 19 key stakeholders, documentary review and a participatory process evaluation workshop with key stakeholders to review collated evidence and contextualize the results. RESULTS: Structured clinical assessment indicated that the PEC provided is consistent with the PEC curriculum, with over 90% of the clinical examination processes conducted correctly. In 4 years, programme monitoring data showed that nearly a million PEC eye examinations had been conducted in every health centre in Rwanda, with 2707 nurses trained. The development of the eye health system was an important enabler in the implementation of PEC, where political support allowed key developments such as inclusion of eye-drops on the essential medicines list, the inclusion of PEC on insurance benefits, the integration of PEC indicators on the health management information systems and integration of the PEC curriculum into the general nursing school curriculum. Challenges included high turnover of primary care nurses, lack of clarity and communication on the future funding of the programme, competing priorities for the health sector and sustained supervision to assure quality of care. CONCLUSIONS: A model of a national primary eye care programme is presented, with service delivery to all areas in Rwanda. Key learning from this evaluation is the importance of strengthening the eye health care system, together with a strong focus on training primary care nurses using a PEC curriculum.

[Improvement of vision through perceptual learning in the case of refractive errors and presbyopia : A critical valuation]. / Sehverbesserung durch perzeptuelles Lernen bei Refraktionsfehlern und Presbyopie : Eine kritische Würdigung.

The idea of compensating or even rectifying refractive errors and presbyopia with the help of vision training is not new. For most approaches, however, scientific evidence is insufficient. A currently promoted method is "perceptual learning", which is assumed to improve stimulus processing in the brain. The basic phenomena of perceptual learning have been demonstrated by a multitude of studies. Some of these specifically address the case of refractive errors and presbyopia. However, many open questions remain, in particular with respect to the transfer of practice effects to every-day vision. At present, the method should therefore be judged with caution.

Vasculopatía coroidea polipoidea bilateral, coexistiendo con degeneración macular asociada a la edad exudativa y atrófica / Bilateral polypoidal choroidal vasculopathy coexisting with exudative and atrophic age-related macular degeneration

OBJETIVO: Presentar el caso clínico de un paciente que presenta vasculopatía coroidea polipoidea (VCP) bilateral y degeneración macular asociada a la edad (DMAE) exudativa y atrófica, su tratamiento. Caso clínico. Mujer de 83 años presenta disminución de agudeza visual en el ojo izquierdo (OI). Al examen presenta DMAE atrófica en el OD, y en el OI una lesión naranja yuxtapapilar con depósitos lipídicos y otra gris subfoveal inferior. En la angiografía fluoresceínica y de verde de indocianina (AVI) se evidencia una membrana neovascular clásica en el OI, y pólipos yuxtapapilares en ambos ojos. Se realiza terapia fotodinámica con inyecciones anti-VEGF con estabilización de lesiones. CONCLUSIÓN: La coexistencia de la vasculopatía polipoidea coroidea y la DMAE exudativa es posible. Ante la sospecha de VCP debe realizarse AVI

OBJECTIVE: To present the case of simultaneous presentation of polypoidal choroidal vasculopathy (PCV) and aged-related macular degeneration (AMD). Case report. An 83-year-old woman presented with decreased vision in the left eye (LE). In the examination there was an orange peripapillary lesion surrounded by lipid exudates and another subfoveal greyish lesion in the LE. Disciform scarring was observed in the right eye. Fluorescein angiography showed a classic neovascular membrane in in the LE fovea. Indocyanine angiography (ICGA) showed a polyp-like peri-papillary aneurysmal dilation in both eyes. The patient was treated with photodynamic therapy and anti-VEFG injections with stabilisation of the lesions. CONCLUSION: PCV and AMD can co-exist in unusual cases. When PCV is suspected, ICGA is mandatory for diagnosis

Accuracy and Efficiency of Orthoptists in Comprehensive Pediatric Eye Examinations.

INTRODUCTION AND PURPOSE: To investigate the level of agreement between orthoptists and medical practitioners in the comprehensive eye examination of children seen in an orthoptist-led triage clinic. PATIENTS AND METHODS: Patient records over a 6-month period were retrospectively reviewed. Those with a presenting complaint related to vision or ocular motility were triaged into the orthoptist-led clinic and included in the study. Patients who did not meet the triage protocol and those who were not assessed by a medical practitioner at a subsequent appointment were excluded from analysis. The clinical findings from the orthoptist and medical practitioner were collected and compared. RESULTS: In total, sixty-three patients were reviewed during the 6-month period and met the inclusion criteria. After the initial comprehensive eye examination with an orthoptist, thirty-two were discharged from hospital and thirty-one were asked to return for a review appointment with a medical practitioner. Agreement between the orthoptists and medical practitioners for the diagnosis of strabismus and/or amblyopia was 84.6% (κ = 0.649, P < 0.001). There was strong agreement between orthoptists and medical practitioners for refractive error of the right eye [τ (19) = 0.352, P = 0.729] and left eye [τ (19) = 1.785, P = 0.090]. Fundus examination comparisons between the orthoptists and medical practitioners showed very high agreement (95.7%). CONCLUSIONS: Orthoptists have the skills necessary to provide comprehensive care of children referred for ocular motility and/or vision related disorders. There was close agreement between orthoptists and medical practitioners when performing comprehensive eye examinations.

[Therapeutic excimer laser treatment of the cornea]. / Therapeutische Excimerlaserchirurgie der Hornhaut.

Concomitant with new innovations in the field of refractive surgery, therapeutic excimer laser applications like phototherapeutic keratectomy (PTK) and topography-guided customised ablation treatment are gaining high importance and undergoing rapid evolution. Nowadays, PTK is an effective treatment modality for superficial corneal pathologies. Primary indications are decreased epithelial adherence, superficial opacifications and an irregular corneal surface. For the right indication and successful treatment of corneal pathologies with PTK, a knowledge of the size, depth and nature of the pathology, as well as the refractive status of both eyes is important. Next to slit-lamp examination, objective measuring systems like the topography, confocal microscopy and the anterior segment OCT facilitate presurgical planning. Regarding the treatment procedure the surgeon can choose between a variety of methods. PTK can be combined with manual epithelial debridement or done by only using the excimer laser. In the case of an irregular corneal surface, depending on the pathology, masking fluids or topography-guided custom ablation protocols can increase the visual outcome. To avoid recurrence of the underlying pathology (e.g., corneal dystrophy, haze), the topical application of 0.02% mitomycin C for 20-60 seconds has proved to be a safe and effective procedure. If the surgeon considers all the patient-related factors carefully and manages to combine the available treatment options correctly, PTK embodies an effective and minimally invasive alternative to lamellar or penetrating keratoplasty.

Plusoptix photoscreening may replace cycloplegic examination in select pediatric ophthalmology patients.

PURPOSE: To determine whether children presenting to a pediatric ophthalmologist and found to have a normal Plusoptix photoscreener (PlusoptiX GmbH, Nuremberg, Germany) result, normal visual acuity (children age 3+), and normal alignment/motility receive additional benefit from a dilated fundus examination. METHODS: The medical records of all children seen at one pediatric ophthalmology practice between 2007 and 2010 who were coded as having had a photoscreening were retrospectively reviewed. Of the total number of records identified, one-half were selected randomly for review. Patients who underwent plusoptiX screening on the first visit were included. Patients with abnormal alignment and/or abnormal vision as well as those referred for examination as determined by a medical or ophthalmic condition that required a dilated fundus examination were excluded. RESULTS: Of 1,377 patients identified, 697 were selected randomly for record review. Of these, 451 had had an initial plusoptiX screening. A total of 222 had a normal result. Of the 190 patients analyzed, cycloplegic examination provided additional diagnostic information for only 4 children: 1 with nonvisually significant congenital cataract, 1 with refractive amblyopia from moderate astigmatism, 1 with moderate hyperopia who later was found to have accommodative esotropia, and 1 with increased cupping but normal IOP. CONCLUSIONS: A normal plusoptiX result, combined with normal alignment/motility evaluation and visual acuity was found to have a 98% negative predictive value for ophthalmic pathology, including significant refractive error. The plusoptiX and an abbreviated eye examination may obviate the need for dilation in select children.

Low-level laser therapy improves visual acuity in adolescent and adult patients with amblyopia.

OBJECTIVE: The purpose of this study was to examine the effects of low-level laser therapy (LLLT) on visual acuity in adolescent and adult patients with amblyopia. BACKGROUND DATA: Currently, amblyopia can be treated successfully only in children. METHODS: In this single-blinded, placebo-controlled study, 178 patients (mean age 46.8 years) with amblyopia caused by ametropia (110 eyes) or strabismus (121 eyes) were included. For LLLT, the area of the macula was irradiated through the conjunctiva from 1 cm distance for 30 sec with laser light (780 nm, 292 Hz, 1:1 duty cycle; average power 7.5 mW; spot area 3 mm(2)). The treatment was repeated on average 3.5 times, resulting in a mean total dose of 0.77 J/cm(2). No occlusion was applied, and no additional medication was administered. Best corrected distant visual acuity was determined using Snellen projection optotypes. In 12 patients (12 eyes), the multifocal visual evoked potential (M-VEP) was recorded. A control group of 20 patients (20 eyes) received mock treatment. RESULTS: Visual acuity improved in ∼90% of the eyes treated with LLLT (p<0.001), increasing by three or more lines in 56.2% and 53.6% of the eyes with amblyopia caused by ametropia and strabismus, respectively. The treatment effect was maintained for at least 6 months. The mean M-VEP amplitude increased by 1207 nV (p<0.001) and mean latency was reduced by 7 msec (p=0.14). No changes were noted in the control group. CONCLUSIONS: LLLT led to a significant improvement in visual acuity in adolescent and adult patients with amblyopia caused by ametropia or strabismus.

Longitudinal study of optic cup progression in children.

PURPOSE: To determine the normative rate of cup-to-disc-ratio (C:D) progression in children and the effect of prematurity and low birth weight on this rate. METHOD: In a single pediatric ophthalmology practice, a single examiner evaluated optic cup size by serial ophthalmoscopy over a minimum of 5 years in 92 patients (184 eyes) without intraocular surgery or optic nerve disease. A cross-sectional analysis of C:D was performed per year of age from 0 to 10 years and linear regression was used to compare C:D progression between preterm and term children and between low versus normal birth weight children. RESULTS: Children exhibited progressive optic cupping. In term children, mean C:D increased by 0.0075 per year. Rate of mean C:D progression was double in children born preterm: 0.0160 (P = .049, comparison to term) per age-year. A similar, nonsignificant trend is observed when comparing low birth weight to normal children (P = .131). CONCLUSION: Prematurity and low birth weight are associated with increased rate of cupping in children. Clinicians should recognize that C:D progression is not a specific sign of glaucoma in children.

Evaluation of actual vs expected photodynamic therapy spot size.

PURPOSE: To determine the accuracy of the photodynamic therapy (PDT) laser spot size on the retina as generated by 2 Food and Drug Administration (FDA)-approved lasers. DESIGN: Prospective observational case series. METHODS: Fundus photographs were taken of 1 eye of each of 10 subjects with the WinStation 4000 fundus photography system (OIS; Ophthalmic Imaging Systems, Sacramento, California, USA); disc size was calculated using OIS software. Slit-lamp photographs were taken of the PDT laser spot focused on the retina adjacent to the optic disc, using various spot sizes in combination with 3 different contact lenses and 2 different lasers. Spot size at the retina was determined by measuring the ratio of disc diameter to spot diameter in Adobe Photoshop (San Jose, California, USA) and applying this ratio to the OIS disc measurements. RESULTS: Spot size at the retina averaged 87% of expected spot size for the Coherent Opal laser (Coherent Inc, Santa Clara, California, USA) and 104% of expected spot size for the Zeiss Visulas laser (Carl Zeiss Meditec Inc, Dublin, California, USA)(P = .002). Multivariate analysis demonstrated that percentage of expected spot size decreased with larger spot diameter (P = .01 for Coherent laser; P = .02 for Zeiss laser). CONCLUSIONS: PDT spot size at the retina appears to be consistently smaller than expected for the Coherent laser while the spot size was consistently within 10% of expected size for the Zeiss laser. The deviation from expected size increased with larger spot size using the Coherent laser.

A clinical evaluation of ophthalmic assessment in children with sensori-neural deafness.

BACKGROUND: Since 1991, children with sensori-neural deafness and their families within Southern Derbyshire have been supported by a multiagency approach to their diagnosis and management. RESULTS: One hundred and twenty-two children were seen at the Child Development Centre for an holistic assessment, and 110 of these children have had an ophthalmic assessment, of whom 48 (43.6%) were found to have ophthalmic abnormalities. These included 43 children (39.1%) with refractive errors, ranging from mild to severe. Of 82 children with uncomplicated deafness, 26 (31.7%) had refractive errors. The prevalence of ophthalmic problems was higher than the prevalence in hearing school children in the literature and in local pre-school children. There were six cases of Usher syndrome. Twenty-one children had more than one eye defect. The findings indicate that deaf and hearing impaired children are two to three times more likely to develop ophthalmic abnormalities than their hearing peers, which makes early detection of paramount importance. An important local outcome has been the establishment of guidelines for ophthalmic assessment to include assessment of vision and screening for Usher syndrome by electro-physiological testing at aged 7 years and above. Screening has been completed to date in 78 children with congenital sensori-neural deafness. CONCLUSIONS: Sensitive and efficient ophthalmic assessment and management are essential for all deaf and hearing impaired children and national guidelines need to be established for both assessment of vision and screening for Usher syndrome, based on further evaluated research.