No abstract available.
Education, Medical ; Vision, Ocular

Optogenetics ; Vision, Ocular

OBJECTIVE: To compare the visual, refractive, and patient-reported outcomes of eyes implanted with one of 3 trifocal intraocular lenses (IOLs). METHODS: This is a cross-sectional, comparative, non-interventional study wherein subjects implanted with FineVision Micro F, AT LISA tri 839MP or AcrySof IQ PanOptix trifocal IOL after phacoemulsification were recruited. Manifest refraction, uncorrected and corrected visual acuity (VA) at distance, intermediate and near vision, contrast sensitivity, modulated transfer function (MTF) values and questionnaire answers were compared among the 3 groups using analysis of variance (ANOVA). RESULTS: Fifty-seven (57) eyes were included in the study: 21 eyes with FineVision (group A), 21 eyes with LISA tri (group B), and 15 eyes with PanOptix IOL (group C). The post-operative mean manifest spherical equivalent was -0.01D, -0.07D, and 0.05D, respectively (p=0.083). Uncorrected distance VA and best-corrected distance VA were similar among the groups. Groups A and C had better uncorrected and corrected intermediate VA at 80 cm and at 60 cm compared to group B. Group A had significantly better uncorrected near visual acuity than groups B and C (p=0.032). Mesopic contrast sensitivity testing showed group C had higher contrast sensitivities without glare in at the spatial frequency of 6 CPD (p=0.038) and with glare at 3 CPD (p=0.039) and at 12 CPD (p=0.009). MTF average height analysis showed that the group A had significantly superior resolution in far targets compared to groups B and C (p=0.001). At near targets, groups A and C had better resolutions compared to group B (p=0.017). There was no significant difference in patient satisfaction for far, intermediate and near VA among the groups. CONCLUSION: Eyes implanted with any of the 3 trifocal IOL designs achieved excellent uncorrected and bestcorrected distance, intermediate and near vision. FineVision and PanOptix provided significantly better intermediate vision than LISA tri at both 80 cm and 60 cm testing distance. FineVision had better near visual outcomes than PanOptix and LISA tri. Patient satisfaction was high in all 3 trifocal IOLS
Lenses, Intraocular ; Vision, Ocular

Visual loss is one of the ocular symptoms resulting from a carotid cavernous fistula (CCF), but has rarely been reported as the sole manifestation in CCF. Visual impairment is known to be associated with a poor outcome unless timely intervention is employed. Herein, the authors report a patient with bilateral rapid progressing visual loss as a sole manifestation in CCF. Vision was successfully restored by transarterial embolization. The authors discuss the necessity of urgent fistula obliteration in patients with visual loss.
Caves ; Fistula ; Humans ; Vision Disorders ; Vision, Ocular

PURPOSE: To compare intraocular straylight in normal and cataractous eyes as the morphology and to compare straylight as the result of subjective symptoms in early cataract cases using the C-quant straylight meter, the only tool to measure light scattering in media. METHODS: Straylight values were measured in 217 normal eyes and 138 cataractous eyes. Cataractous eyes were classified into posterior subcapsular opacity, anterior subcapsular opacity and nucleosclerosis. Straylight values of each group were measured. The 56 early cataractous eyes were categorized into two groups, depending on the presence of subjective symptoms, and each straylight value was measured. The preoperative and postoperative straylight values of early cataracts were also compared. RESULTS: The mean straylight values of normal and cataractous eyes were 1.34 and 2.46, respectively. The value of posterior subcapsular opacity (2.81) was significantly higher than that of anterior subcapsular opacity (2.33) and nucleosclerosis (1.99). The straylight values of early cataracts were significantly higher in the group with subjective symptoms (2.02) than in the group without subjective symptoms (1.56). The postoperative straylight value decreased to 1.42. CONCLUSIONS: The posterior subcapsular cataract showed significantly high intraocular straylight, indicating that light scattering occurred to a greater extent in this group. Light scattering occurred more in early cataractous eyes with subjective symptoms than in eyes without symptoms, and light scattering was reduced after surgery. The C-quant straylight meter, which measures the light scattering in media, can be a useful tool to determine the time of cataract surgery and to evaluate the quality of vision.
Cataract ; Eye ; Light ; Vision, Ocular

This paper introduces the current research progress on effect factors of mobility performance based on simulated prosthetic vision.
Phosphenes ; Prostheses and Implants ; Vision, Ocular

PURPOSE: To determine the range of normal distance stereoacuity in populations with normal vision and the change of distance stereoacuity with age using the Frisby Davis Distance (FD2) stereotest and to evaluate the influence of monocular cues on the FD2 test. METHODS: Ninety-eight subjects between 4 and 73 years old who had no ocular or neurologic diseases were examined. Distance stereoacuity was measured binocularly and monocularly with the FD2 test. RESULTS: According to the results of the FD2 test, the mean distance stereoacuity of patients was 14.74+/-6.02 sec of arc. The monocular threshold with the dominant eye was 182.09+/-58.13 sec of arc. Subjects between 21 and 30 years old showed the best distance stereoacuity of 10.67+/-3.20 sec of arc. A significant decline in distance stereoacuity and monocular threshold were seen in subjects older than 61 (p<0.001). CONCLUSIONS: The normal distance stereoacuity using the FD2 was 14.74+/-6.02 sec of arc, and significant reductions of stereoacuity and monocular threshold were seen in subjects older than 61. Therefore, we have to consider the effect of age on stereoacuity when performing the FD2 test. To take monocular cues into account, the FD2 test should be performed under both binocular and monocular conditions.
Cues ; Eye ; Humans ; Telescopes ; Vision, Ocular

PURPOSE: Reduction malarplasty is a popular aesthetic surgery for contouring wide and prominent zygoma. However a few patients complain postoperative results and want to revise the midfacial contour. We analyzed the etiology of unfavorable results and treated unsatisfied midfacial contours after reduction malarplasty. METHODS: Total 53 patients were performed secondary operation for correction of unfavorable results after primary reduction malarplasty from elsewhere. Midfacial contour was evaluated with plain films and three- dimensional computed tomography. Unfavorable midfacial contours were corrected by secondary malarplasty. Flaring of zygomatic arch was reduced with infracturing technique and prominent zygomatic body was reduced with shaving. Drooped or displaced zygoma complex has been suspended to higher position and fixed with interosseous wiring. As adjuvant procedure, autologous fat injection has been performed in the region of depressed zygomatic body region. RESULTS: The etiology of unfavorable midfacial contour after reduction malarplasty was classified into 7 categories: undercorrection of zygomatic arch(n=8), undercorrection of zygomatic arch and undercorrection of zygomatic body(n=6), undercorrection of zygomatic arch and overcorrection of zygomatic body(n=28), overcorrection of zygomatic body(n=3), simple asymmetry(n=4), malunion(n=2) or nonunion(n=2). Slim and balanced malar contour was achieved with treatment. And most of the patients were satisfied with the results of the surgery. CONCLUSION: To prevent the unfavorable results after reduction malarplasty, complete analysis of facial contour, choice of appropriate operation technique, precise osteotomy under direct vision, and security of zygoma position are important.
Body Regions ; Humans ; Osteotomy ; Vision, Ocular ; Zygoma

OBJECTIVES: Snake or active contours are extensively used in computer vision and medical image processing applications, and particularly to locate object boundaries. Yet problems associated with initialization and the poor convergence to boundary concavities have limited their utility. The new method of external force for active contours, which is called gradient vector flow (GVF), was recently introduced to address the problems. METHODS: This paper presents an automatic initialization value of the snake algorithm for the segmentation of the chest wall. Snake algorithms are required to have manually drawn initial contours, so this needs automatic initialization. In this paper, our proposed algorithm is the mean shape for automatic initialization in the GVF. RESULTS: The GVF is calculated as a diffusion of the gradient vectors of a gray-level or binary edge map derived from the medical images. Finally, the mean shape coordinates are used to automatic initialize thepoint of the snake. The proposed algorithm is composed of three phases: the landmark phase, the procrustes shape distance metric phase and aligning a set of shapes phase. The experiments showed the good performance of our algorithm in segmenting the chest wall by chest computed tomography. CONCLUSIONS: An error analysis for the active contours results on simulated test medical images is also presented. We showed that GVF has a large capture range and it is able to move a snake into boundary concavities. Therefore, the suggested algorithm is better than the traditional potential forces of image segmentation.
Diffusion ; Snakes ; Thoracic Wall ; Thorax ; Vision, Ocular

OBJECTIVE: The ventriculoperitoneal (VP) shunt is the standard therapy for the management of hydrocephalus. Laparoscopic revision of distal shunt malfunction has become popular, but laparoscopic peritoneal shunt placements are not performed often. We present a series of 15 consecutive patients in which VP shunts were placed with laparoscopic assistance. METHODS: From April 2007 to December 2009, 15 patients (aged 44-79 years) with hydrocephalus underwent laparoscopic VP shunt placement. Patients were followed postoperatively for signs and symptoms related to shunt malfunction, shunt infection, and procedure morbidity. RESULTS: All patients tolerated this procedure well, and there were no complications. The benefits of this procedure included shunt placement under direct vision, and reduced risk of both abdominal trauma and intra-abdominal adhesions. CONCLUSION: Laparoscopic-assisted placement of the VP shunt is a good alternative treatment option for hydrocephalus patients.
Humans ; Hydrocephalus ; Laparoscopy ; Ventriculoperitoneal Shunt ; Vision, Ocular