23 research outputs found
Real and Pseudoaccommodation in Accommodative Lenses
In the attempt to manage presbyopia, different intraocular lens designs have been proposed such as monofocal IOLs with monovision or multifocal IOLs. Even though the lenses mentioned offer satisfactory visual results, contemporary ophthalmology has not completely answered the presbyopic dilemma by simulating the accommodative properties of the crystalline lens itself. Accommodative IOLs were designed to fill this gap and provide satisfactory vision for all distances by restoring some degree of “pseudoaccommodation.” Pseudo accommodative capability can be linked to monofocal IOL's as well but the results are not satisfactory enough to fully support unaided near vision. Pseudoaccommodation is a complex phenomenon that can be attributed to several static (i.e., pupil size, against-the-rule cylindrical refractive error, multifocality of the cornea) and dynamic (i.e., anterior movement of the implant itself) factors. Objective measurement of the accommodative capability offered by the accommodative IOLs is extremely difficult to obtain, and different methods such as autorefractometers, retinoscopy, and ultrasound imaging during accommodative effort, ray tracing, or pharmacological stimulation have been developed but the results are sometimes inconsistent. Despite the difficulties in measuring accommodation, accommodative IOLs represent the future in the attempt to successfully “cure” presbyopia
Transepithelial Phototherapeutic Keratectomy Using a 213-nm Solid-State Laser System Followed by Corneal Collagen Cross-Linking with Riboflavin and UVA Irradiation
Purpose. To present a case of a keratoconic patient who underwent epithelial removal with transepithelial phototherapeutic keratectomy (t-PTK) using a 213-nm solid-state laser system followed by corneal collagen cross-linking (CXL) with riboflavin and ultraviolet-A (UVA) irradiation. Methods. Case report. Results. A twenty-four-year-old male with keratoconus underwent CXL treatment after epithelial removal with t-PTK using a solid-state laser system. No intra- or early postoperative complications were found. One month postoperatively, uncorrected visual acuity (UCVA) improved from 20/63 to 20/32 while best spectacle- corrected visual acuity (BSCVA) improved from 20/40 to 20/25. Corneal topography revealed a significant improvement which remained stable during the six-month followup period. Conclusions. Epithelial removal with t-PTK before CXL could improve patient's visual outcome
Clinical Study Long Term Followup of Photorefractive Keratectomy with Adjuvant Use of Mitomycin C
properly cited. Purpose. To study the long term refractive and visual outcomes of photorefractive keratectomy (PRK) with intraoperative application of mitomycin C (MMC). Methods. This study included 37 eyes who received myopic PRK; after photoablation, a sponge soaked in 0.02% MMC solution was applied in all corneas for 2 minutes. Efficacy, safety, predictability, and stability of PRK MMC were evaluated. Endothelial cell density was evaluated at the last postoperative interval. Results. Mean preoperative spherical equivalent (SEQ) was −6.03 ± 1.87 D (diopters) and reduced to −0.09 ± 0.53 D at the last postoperative examination. Mean followup was 44.73 ± 18.24 months. All the eyes were in the ±1.00 D of attempted versus achieved SEQ at the one-year follow-up interval. Furthermore, 95% of the eyes did not lose lines or gained 1 to 2 lines of CDVA, while 5% lost 1 line. At the third postoperative month, 89% of the eyes either were clear or had trace haze, while 4 eyes had mild haze; by the 12-month postoperative interval, none of the eyes demonstrated haze. Mean endothelial cell density (ECD) at the last postoperative interval was 2658 ± 153 cells/mm 2 . Conclusions. PRK, with intraoperative use of MMC, demonstrates stable refractive and visual outcomes up to 44 months after surgery
TFOS European ambassador meeting:Unmet needs and future scientific and clinical solutions for ocular surface diseases
The mission of the Tear Film & Ocular Surface Society (TFOS) is to advance the research, literacy, and educational aspects of the scientific field of the tear film and ocular surface. Fundamental to fulfilling this mission is the TFOS Global Ambassador program. TFOS Ambassadors are dynamic and proactive experts, who help promote TFOS initiatives, such as presenting the conclusions and recommendations of the recent TFOS DEWS II™, throughout the world. They also identify unmet needs, and propose future clinical and scientific solutions, for management of ocular surface diseases in their countries. This meeting report addresses such needs and solutions for 25 European countries, as detailed in the TFOS European Ambassador meeting in Rome, Italy, in September 2019
ND:YAG laser for preretinal hemorrhage in diabetic retinopathy
Purpose: To present fundus images of a case with severe preretinal hemorrhage in diabetic retinopathy that was treated with posterior hyaloidotomy with an Nd:YAG laser. Observations: A 35-year-old diabetic patient presented with sudden painless loss of vision due to severe preretinal hemorrhage over the macular area and high risk proliferative diabetic retinopathy. Her visual acuity was counting fingers. Posterior hyaloid face was treated with Nd:YAG laser (posterior hyaloidotomy). Panretinal laser photocoagulation was first performed to control the proliferative diabetic retinopathy. Blood drained inferiorly into the vitreous cavity with clearance of the premacular area. Conclusions and importance: Prompt treatment with Panretinal laser photocoagulation followed by posterior hyaloidotomy with the YAG laser is a viable option in order to avoid further proliferative diabetic retinopathy complications and vision loss. The current image clearly depicts treatment efficacy. Keywords: Diabetic retinopathy, Preretinal hemorrhage, YAG laser, Panretinal photocoagulatio
Follow up of intraocular lens subluxation with a combined topographer/aberrometer
Purpose: To report a 36-year-old patient with intraocular lens (IOL) subluxation that was followed for IOL stability with evaluation of images captured with the iTrace combined aberrometer/topographer.
Methods: The patient had undergone phacoemulsification with IOL implantation for congenital cataract 15 years before. He presented with bilateral IOL subluxation, more severe in his right eye. Right eye was operated for IOL exchange and left eye was followed with the iTrace images. The images were captured with an infrared camera, and the pupil, the pupil center and the corneal vertex could be detected. The subluxated IOLs edge was visible through infrared light retroillumination. IOL position was evaluated with respect to the pupil, the pupil center and the corneal vertex.
Results: The patient's left eye was followed for 7 months, and IOL position was noted to be stable. Thus no intervention was planned.
Conclusion: Evaluation of iTrace images is a reliable method to follow eyes with IOL subluxation
In vivo evaluation of blue-light attenuation with tinted and untinted intraocular lenses
In this paper we present a method for mapping streaming applications, with real-time requirements, onto a reconfigurable MPSoC. In this method, the performance of the hardware architecture (the reconfigurable Processing Element, the Network Interface and the Network-on-Chip) is integrated in the performance models of the applications. In this way the performance of the mapped application can be determined at run-time. A predictable NoC (guaranteed bandwidth and bounded latency), a predictable Network Interface and a predictable Processing Element are key requirements for our approach
Acute Zonal Occult Outer Retinopathy with Atypical Findings
Background. To report a case of acute zonal occult outer retinopathy (AZOOR) with atypical electrophysiology findings. Case Presentation. A 23-year-old-female presented with visual acuity deterioration in her right eye accompanied by photopsia bilaterally. Corrected distance visual acuity at presentation was 20/50 in the right eye and 20/20 in the left eye. Fundus examination was unremarkable. Visual field (VF) testing revealed a large scotoma. Pattern and full-field electroretinograms (PERG and ERG) revealed macular involvement associated with generalized retinal dysfunction. Electrooculogram (EOG) light rise and the Arden ratio were within normal limits bilaterally. The patient was diagnosed with AZOOR due to clinical findings, visual field defect, and ERG findings. Conclusion. This is a case of AZOOR with characteristic VF defects and clinical symptoms presenting with atypical EOG findings